Total Hip Arthroplasty

The total hip arthroplasty (THA), a common procedure performed in many acute care hospitals, is used in cases of severe joint damage resulting from osteoarthritis, rheumatoid arthritis, and avascular necrosis. It is one of the most successful and cost-effective interventions in medicine.After THA surgery, many patients typically are able to return to participation in activities that were too painful before surgery.

Indications

The most common indications for a THA are as follows:

• Pain. Pain is the principal indication for hip replacement. This includes pain with movement and pain at rest. A significant amount of pain may be reliably relieved as early as 1 week after surgery.
• Functional limitations. Capsular contractions and joint deformity cause a decreased ROM in the hip with subsequent functional restrictions.
• Loss of mobility. There are certain patient subgroups in which joint stiffness, without hip pain, is an indication for surgery. These groups include patients with ankylosing spondylitis.
• Radiographic indications of intra-articular disease. Although radiographic changes are considered in the decision to operate, the more significant determinant is the severity of symptoms. Arthroplasty of the hip is considered in the presence of osteoarthritis, aseptic necrosis, congenital abnormalities, rheumatoid arthritis, and Paget's disease, among others.

Contraindications for THA, both absolute and relative, include but are not limited to the following:

• Active infection.
• Inadequate bone stock or periarticular support.
• Younger age. Although most THAs are performed in patients between 60 and 80 years of age, hip replacement is occasionally performed in younger patients including those in their teens and early 20s.
• Obesity.
• Planned return to high-impact sports or occupations.
• Arterial insufficiency.
• Neuromuscular disease.
• Mental illness.

Procedure

The hip is a polyaxial synovial joint consisting of a modified ball and socket articulation between the acetabulum of the pelvis and the head of the femur. Both portions of this articulation are replaced during total hip arthroplasty. A bipolar prosthesis consisting of an outer metal shell that articulates with acetabular cartilage via a snap-fit attachment to the ball of the femoral component is often used. A number of factors determine the procedure used by the surgeon including surgeon familiarity and comfort, patient size, and scars from previous surgery or trauma.

The first successful THA was developed by John Charnley in the 1960s. This procedure involved a transtrochanteric lateral approach. Three other approaches have evolved since: the anterolateral approach, the direct lateral approach, and the posterolateral approach. Controversy remains as to which approach results in the lowest complication rate.

• Anterolateral approach. There are numerous variations of the anterolateral approach. All variations approach the hip through the interval between the tensor fascia lata and the gluteus medius muscle. Some portion of the hip abductor is released from the greater trochanter, and the hip is dislocated anteriorly.

• Direct lateral approach. The direct lateral approach leaves the posterior portion of the gluteus medius attached to the greater trochanter. Because the posterior soft tissues and capsule are left intact, this approach is preferred in the more noncompliant patients to prevent postsurgical dislocation.

• Posterolateral approach. The posterolateral approach gains access to the hip joint by splitting the gluteus maximus muscle. The short external rotators are then released, and the hip abductors are retracted anteriorly. The femur is then dislocated posteriorly. Although the posterior approach may allow for maintenance of abductor strength, it generally results in a higher postsurgical dislocation rate.

Both the anterolateral and the posterolateral approaches appear to result in decreased blood loss and fewer hematomas when compared with the transtrochanteric approach. The advantages of the anterolateral approach are the lower dislocation rates and the excellent acetabular exposure. The disadvantage of the anterolateral approach is an increase in antalgic gait (at least temporarily). Although several studies imply weakening of the abductor muscles as a result of the anterolateral approach, only one study has found a statistically significant increase in weakness of the abductors with this approach.

Although the posterolateral approach has remained essentially unchanged, the anterolateral approach has been modified by several surgeons to decrease gluteus medius disruption and, it is hoped, to decrease postoperative abductor muscle dysfunction and resultant limp. However, no studies from the past decade have yet compared abductor muscle dysfunction in the posterolateral approach versus a modified anterolateral approach. In obese patients or those undergoing revision surgery who have excessive scar tissue, the aforementioned surgical approaches may not provide adequate exposure. In these circumstances, a trochanter osteotomy can be performed. After the prosthesis has been inserted, the trochanter is reattached by wires or screws.

A number of criteria must be met for the long-term success of the implant. These include adequate fixation, adequate strength and wear resistance, and biological and biomechanical compatibility.

• Fixation. Two types of fixation are recognized: cemented and cementless. Methylmethacrylate cement has the useful property of approximately 90% of its polymerization occurring during the first 10 minutes following application. The acrylic cement's resistance to compression load is usually adequate to allow weight-bearing as tolerated (WBAT) on the affected extremity early in the rehabilitation program often on the first or second postoperative day. However, there are a number of disadvantages to the traditional method of cementing. These include poor tensile and compressive strengths of the acrylic cement, and the high incidence of component loosening in younger, more active patients.Cementless technology was introduced as a strategy to improve the results of cemented hip replacement in the 1970s. Excellent bone ingrowth has been demonstrated in porous-coated implants inserted without cement provided there is good bone quality. Bone in growth occurs during the first six postoperative weeks. Whether the patient is restricted to nonweightbearing (NWB) status or allowed to partially weight-bear (PWB) is determined by the surgeon and may depend on the mechanical fixation of the prosthesis within the acetabulum and femur. There is no universal agreement on indications for cementless versus cemented hip replacement. However, it is generally agreed that the primary indication for a cementless THA is the young, active individual, usually younger than age 65 physiologically.
• Adequate strength and wear resistance. In the early years of hip replacement, fracture of the femoral stem was a problem. This problem has been resolved largely by the use of improved metal processing. Polyethylene wear undoubtedly has been the major long-term problem of THA. The use of a ceramic femoral head has been advocated, especially in young, active patients, because it produces less polyethylene wear compared with a conventional metal femoral head.
• Biological compatibility. The primary fixation mode of cementless acetabular components is mechanical and is dependent on a physical interlock between the cup and the reamed acetabulum.Secondary fixation is biological and is achieved by means of bone growth onto or into the substrate at the implant-bone interface. The fixation surface of cementless metal-backed sockets typically consists of a porous coating of beads or fiber metal, a titanium plasma-sprayed surface, various sintered surface textures, or a bioactive ceramic coating such as hydroxyapatite or tricalcium phosphate. For long-term stability, it is essential that this direct bond between the implant and the bone be maintained. The production of particulate wear debris from implant materials and subsequent osteolysis has been recognized as the major cause of long-term failure in THA. Using cell cultures, Vermes and colleagues demonstrated that metallic particulate debris affected osteoblast function through two distinct mechanisms: a direct negative effect on cellular function by the phagocytosis itself, and an effect mediated through cytokines that cause a downregulation of procollagen gene expression along with decreased cell proliferation. Moreover, this study demonstrated that osteoblasts stimulated by particulate debris produced interleukin-6 and prostaglandin E2, leading to the activation of osteoclast function.
• Biomechanical compatibility. Prosthetic impingement resulting from poor positioning, the head–neck ratio, and the presence of a modular head with an extended sleeve has been implicated in decreasing the postsurgical ROM at the hip after THA. Additional factors, such as osseous impingement and soft-tissue tension, can further decrease the range.

Several complications are associated with THA. These include, but are not limited to the following:

• Deep vein thrombosis (DVT). DVT remains the most common and potentially lethal complication following either elective or emergency surgery of the hip in adults. Peak incidence, which is proably between 40% and 60% for distal (calf) vein thrombosis, and 20% for proximal (popliteal, femoral, and iliac) thrombosis, occurs during the second and third week postsurgery. However, the period of increased risk can be up to 3 months after surgery. Even with prophylaxis, the incidence of angiographically proven asymptomatic pulmonary embolism has been reported to be approximately 20%.
• Heterotopic ossification. Heterotopic ossification (HO) is a well-known complication of surgical approaches to the hip that involve dissection of the gluteal muscles and is the most common complication following THA. There is also a strong association between HO and spinal cord injury, with lesions occurring at multiple sites and showing a strong propensity to recur, and in patients with traumatic brain injury. The exact mechanism for heterotopic bone formation has not been thoroughly elucidated, although trauma to the muscles during surgery appears to be a major contributing factor in provoking pluripotent mesenchymal cell differentiation into osteoprogenitor cells. This process begins as soon as 16 hours after injury and is maximal at 36–48 hours. Additional reported risk factors for HO include thoracic and abdominal trauma, male gender, T-type fracture, delay in fracture fixation, and closed head injury.Differentiating early HO from lower extremity deep venous thrombosis (DVT) can prove to be extremely difficult as both conditions can present with the same symptoms of lower extremity pain, swelling, and erythema. HO and DVT have been positively associated, perhaps because the mass effect and local inflammation of HO encourage adjacent thrombus formation by venous compression and phlebitis. HO often begins as a painful palpable mass that gradually becomes nontender and smaller but firmer to palpation. Bone scan is the method of choice for earliest detection.
• Femoral fractures. Fracture of the femur in association with THA is a challenging complication that has been well described.The prevalence of these fractures has ranged from 0.1% (7 of 5400)  to 20%. Risk factors include female gender, rheumatoid arthritis, cortical perforation, osteopenia, osteoporosis, preoperative femoral deformity, a revision operation, osteolysis, and loosening of the stem.
• Dislocation. Dislocation of the total hip replacement remains a common and potentially extremely problematic complication. As many as 85% of dislocations are reported to occur within 2 months after THA.Dislocation is more common in elderly people, particularly those with impaired cognition and balance and vibration sensitivity. It occurs more commonly in women. There is also a correlation with history of trauma or developmental dysplasia of the hip. Patients with cerebral dysfunction or excessive alcohol use are also at higher risk. Dislocation rate is a factor of many other requirements including component position, technical errors, imbalance of tissues, surgical approach, and patient compliance.
• Neurovascular injury. A review of the literature reveals that the prevalence of nerve palsy following THA varies from 0.08% to 7.5%, depending on the study with an overall prevalence of 1%. The peroneal division of the sciatic nerve is involved in almost 80% of cases, with the femoral nerve and the obturator nerve involved less frequently.There are many proposed causes for neuropathy associated with THA, including direct trauma; excessive tension because of an increase in limb length, or offset, or both; bleeding, or compression, or both, by a hematoma; and unknown.

Presurgery Evaluation and Education

At many institutions, patients attend a presurgery class 7–10 days before surgery. These preoperative training sessions have been shown to improve motivation, understanding, and compliance during rehabilitation of the postsurgical patient. The class instructors usually include a case nurse, dietitian, and physical therapist.

• The case nurse reviews how to make the home safe; what to expect before, during, and after surgery; how to prevent dislocations; what medications will be used; and what type of transport is needed to bring the patient home. He or she also brings in pictures of the operating room and samples of equipment. A case nurse reviews the patient's history before admission, and a home assessment is performed 6 weeks preoperatively.
• The dietitian discusses which foods help healing, and how to cope with decreased appetite and depression that are both common after surgery.
• The physical therapist discusses the postsurgical physical therapy program and shows each patient how to use an appropriate assistive device for gait. An assessment is made of general strength, ROM, neurologic status, endurance, and safety awareness. The patient receives instruction on the early postoperative exercises, deep breathing and coughing, pertinent hip precautions, and safe transfer techniques. Upper body exercises are taught to help the patient walk with an assistive device (crutches, or walker) and to transfer. Function can be assessed using the Harris Hip Scale or a similar standard outcome measurement for the hip.

Patients and their caregivers are encouraged to ask questions and complete forms used to calculate their current function. The patients receive booklets on diet, exercise, postsurgical precautions, home safety, and discharge planning.

Postsurgical Rehabilitation

Following the surgery, thromboembolic disease (TED) hose are placed on the patient. For patients who have undergone either a posterolateral approach or a transtrochanteric approach, a triangular foam cushion is strapped between the legs to keep the hip in an abducted position. Patients at a high risk of dislocation, such as those who have undergone a postrevision arthroplasty or those with cognitive impairments, may need to wear a hip abduction orthosis that maintains the hip in abduction for 6–12 weeks. These orthoses may make ambulation difficult if the abduction is more than 5–10 degrees.

The postsurgical examination is divided into three components: patient history, the systems review, and tests and measures. The selection of examination procedures and the depth of the examination are based on the patient age, severity of the problem, the acute stage of recovery, the early phase of rehabilitation, home situation, and other relevant factors. The relevant tests and measures for this patient population include the Fatigue Severity Scale, the Harris Hip Scale, Manual muscle testing of the upper extremity (UE) and nonoperated lower extremity (LE), Elderly Mobility Scale, Braden Scale for Predicting Pressure Sore Risk, and ROM with goniometry. Reexamination is conducted on a daily basis and at discharge from the acute care phase. Indications for reexamination include new clinical findings or failure to respond to physical therapy interventions. The reexamination and discharge includes the same tests and measures used at initial examination.

Most important is to avoid during the examination those motions and positions that are contraindicated according to surgical approach:

• For the posterolateral approach, this involves avoidance of flexion of the hip beyond 90 degrees, and minimal adduction or internal rotation of the hip.
• Following a lateral or anterolateral approach, the patient should avoid extension, external rotation, and adduction across midline.

These precautions must be maintained for at least 6 weeks, or until the surgeon decides otherwise.

A review of the literature reveals inconsistent practice patterns in the physical therapy management of THA patients. The postsurgical rehabilitation program that follows is based on the consensus found.The program is divided into two components: the inpatient stay, and the outpatient course of intervention.

Phase 1: Inpatient Phase (24 Hours to Discharge)

This phase typically involves four to eight physical therapy sessions.

Table: Factors That May Modify Frequency of Visits

Accessibility and availability of resources.	Overall health status.
Adherence to the intervention program.	Pain and early movement tolerance.
Age.	Potential discharge destinations.
Cognitive status.	Premorbid conditions.
Comorbidities.	Probability of prolonged impairment, functional limitation, or disability.
Complications from surgery.	Psychological and socioeconomic factors.
Concurrent medical, surgical, and therapeutic interventions.	Psychomotor abilities.
Decline in functional independence.	Severity of the current condition.
Level of impairment.	Social support.
Level of physical function.	Stability of the condition.
Nutritional status.	Stability of vital signs.

 Twice daily visits are recommended over one daily visit. Ideally, the patient will have attended a preoperative training session. Basic physical therapy begins on postoperative day 1, provided no direct complications from the surgery have occurred. Patients should be evaluated routinely for peripheral nerve function on a daily basis. If a palsy is detected, a knee immobilizer (for femoral nerve palsy) should be used with ambulation, additional exercises focusing on strengthening the affected muscles and stretching the antagonists to prevent joint contractures should be prescribed, and the patient should be fitted with the appropriate orthotic (ankle foot orthoses [AFOs] with sciatic palsy) to allow physical therapy to proceed.

Goals

• Prevent postsurgical complications, including
  • DVT
  • postoperative infection
  • detrimental effects of immobilization
  • pulmonary embolus
• Reports of pain to be 7/10 or less. Increasing or severe buttock pain may indicate a hematoma.
• Patient to achieve an independent or minimally supervised functional level for
  • bed mobility including transfers in and out of bed
  • transfers on and off a commode
  • transfers up and down from a chair of varying heights
• Gait training at a household level with the appropriate assistive device for 100 feet, and with the least amount of assistance that renders the patient safe.
• Independence with stair negotiation (one or more steps), consistent with the patient's home environment, with appropriate assistive device and with and without a handrail.
• Independence with the home exercise program that will be performed 2–3 times a day.
• Independence with adherence to THA precautions and correct application of them into any permitted functional activity.

The patient should be repositioned every 2 hours by the nursing staff. The skin, especially on the heels, is checked regularly for breakdown. The patient is provided with information on assistive devices, such as an elevated seat, a long handled shoehorn, elastic laces, and a long handled reacher. A referral for occupational therapy may be necessary for specific instructions on activities of daily living such as dressing and bathing.

Electrotherapeutic and Physical Modalities

Modalities that reduce pain and swelling (ice and elevation) are initiated as early as possible. With the physician's permission, electrical stimulation can be used for edema reduction, muscle reeducation, and pain control.

Therapeutic Exercise and Home Program

The therapeutic exercise program typically begins within 24 hours after the surgery.

Exercises may include the following:

• Resistive exercises to the uninvolved extremities.
• Ankle pumps (not circles, so as to prevent any inadvertent rotation at the hip) for both lower extremities.
• Quadriceps sets, gluteal sets, and hamstring sets of the involved leg.
• Deep-breathing and coughing exercises.
• Leg dangling over the edge of the bed (day 2) and sitting in a hip chair. The clinician must check the patient's blood pressure and pulse during initial sitting and standing activities. If orthostatic hypotension occurs, a tilt table or a reclining, high-backed chair can be used to gradually bring the patient to an upright position.
• Active and isometric hip abduction of the involved leg (day 2).These exercises are deferred initially if a trochanteric osteotomy has been performed.
• Active assistive hip and knee flexion (heel slides) to the involved limb. These are performed while maintaining the hip ROM within the guidelines specified by the surgeon (day 2). The patient can use a sheet to help with this exercise.
• Short arc quads of the involved leg (day 2).

Functional Training

On the first day after the surgery, the clinician begins transfer training and instructs the patient with regard to bed mobility. Training includes transfers from supine to sitting on the bed, and then from sitting to standing, while observing all of the necessary hip precautions. If permitted by the surgeon, the patient can be shown how to transfer to an appropriate bedside chair. The patient is encouraged to sit on the chair for about 30–60 minutes, depending on tolerance, which can be measured using the vital signs of pulse and blood pressure, as well as subjective complaints such as light headedness or dizziness.

Gait training with crutches (younger more active patients) or walker (more elderly patients) is usually begun on the second day following surgery. The patient's assistive device is adjusted to the correct height. Close attention must be paid to these patients during gait training because of their balance deficiencies and the potential for temporary postural hypotension.

• The weight-bearing status of the patient with a noncemented THA is decided by the surgeon. It can vary from NWB to toe-touch weight bearing, to partial weight bearing (20–25 lbs pressure). Toe-touch weight bearing involves applying no more than 10% of body weight. It has been described as analogous to walking on eggshells. Partial weight bearing is a difficult concept for most patients to grasp. Using a bathroom scale, or a description such as "1/10 of body weight" (depending on the patient's weight) usually helps. Force platforms are also available to measure these forces directly and can provide beneficial feedback for the patient.
• The weight-bearing status for the patient with a cemented THA is usually partial weight bearing for 6 weeks prior to full weight bearing, although some surgeons permit weight bearing as tolerated with a walker immediately.

Normalization of the gait pattern should be taught early. Stand-to-pivot transfers should also be taught to prevent the patient from rotating at the involved hip.

Stair negotiation, based on the patient's home situation, is typically taught on day 3.

Home Care Phase (1–7 Days)

If functional independence is required before a patient returns home, the patient is typically transferred to a dedicated rehabilitation unit, or an acute or subacute care setting. If adequate home care and safe transport are available, the patient is allowed to return home.

In one study, Munin and colleagues determined certain markers that were predictive of patients who would require an inpatient rehabilitation program versus direct discharge to home. Those patients determined to be at high risk were 70 years of age or older, 51% lived alone, and many had a number of comorbid conditions. The average length of stay for comprehensive inpatient THA rehabilitation is 7–10 calendar days.

A physical home care assessment usually occurs within 24 hours after hospital discharge. During this phase, the role of the physical therapist is to address any safety concerns including moving or adjusting the height of furniture, the removal of any throw rugs, review of sitting and sleeping positions and hip precautions, and progression of home exercise program.

Weight-bearing exercises, such as seated heel raises and mini-squats against a wall are usually introduced at this time.

Phase 2: Outpatient Phase (Week 2–8) This phase typically lasts for 2–6 weeks and may involve six to nine physical therapy sessions. The staples are usually removed after 12–14 days. Goals Reports of pain to be 5/10 or less. Hip ROM to be 70–90 degrees of hip flexion. Balance and proprioception to be at 50% of the uninvolved leg, as measured by single-leg stance time, if weight-bearing status permits. Strength to be 3/5–4/5 on the involved lower extremity. A positive Trendelenburg test at the end of this phase indicates a need for additional outpatient therapy for gait training and strengthening. Patient to achieve independence with all transfers. Patient to have a normal gait pattern with a quad cane or straight came, held on the contralateral side on level surfaces. Electrotherapeutic and Physical Modalities Superficial thermal modalities may be used in this phase. Therapeutic Exercise Weakness following a THA is common and can lead to diminished protection of the implant fixation surfaces during activities. Flexibility exercises are performed within the limitations of hip precautions to the following muscle groups: Iliopsoas. Quadriceps and rectus femoris. Gastrocnemius and soleus. Hamstrings. Lower extremity strengthening exercises include NWB exercises of heel slides, hip abduction in the supine position, straight leg raises, and short arc quads weight-bearing exercises of weight shifting, modified wall slide squats to approximately 45 degrees of hip flexion, modified lunges (anterior and lateral), and step-ups and step-downs Upper extremity strengthening exercises are initiated as needed. Cardiovascular conditioning is begun with the use of an upper body ergonometer. Neuromuscular Retraining Biomechanical ankle platform system (BAPS) board exercises in sitting or standing position, with weight-bearing restrictions observed. Biased stance balance-and-reach activities involving reaching arms forward at shoulder height and waist height. Functional Training Gait training is performed on level and stairs with appropriate assistive device. The patient can be advanced to a single-point cane as and if appropriate. A four-point cane may be used as an interim device. Transfers are progressed to all surfaces, when permitted. Patients are usually permitted to drive 6–8 weeks after surgery. Driving reactions, including the delay and force of a brake application after an emergency signal, may be impaired, especially following right hip replacement. Manual Therapy Manual therapy techniques include soft tissue techniques and mobilization of the posterolateral or anterolateral hip scar mobilization contract–relax techniques within the limits of the hip precautions passive stretching of lateral hip, knee, and lumbar spine within the limits of the precautions Phase 3 (Week 9 +) Goals Reports of pain to be 2/10 or less with activity of the involved leg, and 0/10 at rest. Hip ROM to be at 90 degrees of flexion. Involved lower extremity muscle strength to be at 4/5 with manual muscle testing. Patient to be independent with ambulation, and with no gait dysfunction. Balance and proprioception to be at 80%, compared with the uninvolved leg, as measured by single-leg stance time. Patient to be independent with stair negotiation without an assistive device. Patient to demonstrate functional independence in activities of daily living. Patient to achieve return to employment or previous hobbies, as indicated. Therapeutic Exercise Phase 1 exercises are progressed, with the addition of increased resistance as appropriate. Weakness of the hip muscles has been shown to exist up to 2 years postsurgery. Therefore, the therapeutic exercise program should be continued for at least 1 year, and preferably longer, until the involved limb strength is equal to that of the uninvolved. Treadmill exercises are initiated, as well as other low-impact forms of conditioning, as appropriate. Neuromuscular Retraining Single-leg balance-and-reach exercises are performed including reaching arms forward, reaching opposite leg forward, and reaching opposite leg laterally. Mark Dutton, PT,Orthopaedic Examination, Evaluation, and Intervention 2nd edition McGraw-Hill 2008  ISBN: 0071474013  https://www.aofoundation.org/wps/portal/!ut/p/c1/04_SB8K8xLLM9MSSzPy8xBz9CP0os3hng7BARydDRwML1yBXAyMvYz8zEwNPQwN3A6B8JG55AyOSdBtYBLgZGDmZ-huaBAcYgeTx6_bzyM9N1S_IDY0od1RUBACWqcev/dl2/d1/L2dJQSEvUUt3QS9ZQnB3LzZfQzBWUUFCMUEwOEVSRTAySjNONjQwSTEwRzA!/?contentUrl=%2fsrg%2f31%2f04-Approaches%2f2008%2f31_Nr52_Appr_Direct-lateral.jsp&bone=Femur&segment=Proximal&showPage=approach&classification=31-B3&treatment=&method=Arthroplasty&implantstype=&redfix_url=1284974569031&approach=Direct%20lateral%20approach http://www.jisrf.org/total_hip_replacement.htm http://www.hopkins-arthritis.org/physician-corner/cme/rheumatology-rounds/hip_knee_arthroplasty_rheumrounds9.html

Total Knee Arthroplasty

Total knee arthroplasty (TKA) has been shown to be an effective long-term intervention for the elderly population to relieve knee pain, improve function, increase social mobility and interaction, and contribute to psychological well-being.

 

Indications

Although pain and loss of function are the primary reasons for a TKA, the procedure can also be used to correct knee instability and lower extremity alignment and for the treatment of isolated but severe patellofemoral disease. Because TKA is generally contraindicated in younger and more active patients, those with unicompartmental osteoarthritis of the knee may be considered candidates for a high tibial osteotomy or a distal femoral osteotomy. The high tibial osteotomy is used with isolated medial compartment arthritis. The distal femoral osteotomy is used in lateral compartment arthritis. The short-term results for these procedures have been very successful, even to the point where the need for TKA is eliminated. However, permanent pain relief with high tibial osteotomy is as yet unlikely.

Absolute and relative contraindications for a TKA include but are not limited to

• active infection of the knee
• significant genu recurvatum
• severe obesity
• return to high-impact sports or occupations
• arterial insufficiency
• neuropathic joint
• mental illness

Procedure

Several techniques are at the surgeon's disposal. The choice of approach is determined by surgeon's knowledge and comfort. Three approaches are commonly described: anterior, subvastus, and lateral.

• Anterior approach. The anterior approach is generally through an anterior midline longitudinal skin incision and median parapatellar arthrotomy. The advantages of this approach include its extensile potential and its wide exposure medially and laterally. The disadvantages include its violation of the quadriceps mechanism, and the potential for patellar devascularization.

• Subvastus approach. The subvastus approach uses the same midline anterior skin incision as the anterior approach. The advantages of this approach include maintenance of the quadriceps mechanism with decreased postoperative pain and earlier functional recovery.⁸³ The disadvantages include its somewhat limited exposure.

• Lateral approach. The lateral approach occurs lateral to the patella and through the medial edge of Gerdy's tubercle. Proponents of this technique feel that it is a superior method in the correction of valgus deformity.

Most primary arthroplasties rely upon the patient's anatomy to offer stability to the articulation. Anatomic structures that can offer  stability include the posterior cruciate ligament (PCL) and a balancing of the soft tissues around the knee. The fate of the PCL in primary TKA is controversial. If the PCL is sacrificed, a posterior stabilizer (see below) is used. However, the long-term results of PCL-retaining and posterior-stabilized TKAs are similar. PCL substitution may be indicated in patients requiring TKA who present with end-stage degenerative joint disease with varus or valgus malalignment and associated flexion contracture, with a combined deformity greater than 15 degrees.

Many early designs of TKA replaced only the tibiofemoral joint and did not address the patellofemoral articulation. The posterior stabilizer was developed to increase the arc of motion of these earlier models and thereby improve the functional results of TKA. Although the ROM improved substantially with these components, patellofemoral complications emerged as a major problem after knee replacement. Errors in sizing, alignment, and rotation of the tibial and femoral component were eventually appreciated as contributing factors to many of these patellofemoral problems. In addition, many of these complications appear to be secondary to patellar resurfacing which may be a part of the procedure. Whether to resurface the patella remains among the most controversial topics in TKA.

Surprisingly high loads are transmitted across the patellofemoral articulation. Following a knee replacement, there is a decrease in the contact area and consequent increase in the contract stress. A study by Matsuda and colleagues showed that resurfacing the patella decreased the contact area to a greater degree compared with not resurfacing the patella. In addition, kinematic studies of motion of the patellofemoral joint after knee replacement have consistently shown some degree of altered kinematics.

Postsurgical Rehabilitation

Preoperative instruction is believed to be invaluable in the early postoperative setting. Preoperative instruction should include education regarding the ice-compression-elevation program, ROM exercises, isometric quadriceps strengthening, patellofemoral mobilization, and gait training with the appropriate postoperative assistive devices.

Complications associated with TKA include the following :

• Thromboembolic disease.
• Fat embolism.
• Poor wound healing.
• Infection.
• Periprosthetic fractures.
• Neurologic problems. Peroneal nerve palsy is the most common neurologic complication of TKA.
• Vascular problems. Injuries to the superficial femoral, popliteal, and genicular vessels have all been reported following TKA.
• Arthrofibrosis.
• Disruption of the extensor mechanism.

Postoperative rehabilitation for primary TKA continues to be studied in an effort to decrease the cost while still providing the quality of clinical results expected by the surgeon and the patient.

A review of the literature reveals inconsistent practice patterns in the physical therapy management of TKA patients.The postsurgical rehabilitation program that follows is based on the consensus found. The program is divided into two components: the inpatient stay and the outpatient course.

The success of the rehabilitation program for this patient population is dependent on knowledge of the surgical procedure, communication with the surgeon and the patient, and above all, the ability of the rehabilitation team to educate the patient to participate actively in the treatment program.

Phase 1: Inpatient Phase (1 Dayuntil Discharge)

This phase typically involves 4–10 physical therapy sessions.

The subject of continuous passive motion (CPM) device use following a TKA has been debated for years, with some surgeons advocating and others opposing its use. The use of a CPM device has been promoted as a means to facilitate a more rapid recovery by improving flexion range, decreasing length of hospital stay, and lowering the amount of narcotic use. However, studies have shown that the effect of CPM devices on analgesia consumption, ROM, hospital stay, and complications has been variable:

• Data support the use of CPM to decrease the rate of manipulation for poor ROM after TKA.
• The long-term ROM probably is not increased by the use of CPM after TKA.
• Although it appears that the use of a CPM device does help regain knee flexion quicker, it is not as effective in the enhancement of knee extension.
• Knee impairments or disability are not reduced with the use of a CPM at discharge from hospital.
• Because of standardized inpatient hospital clinical pathways, the length of hospital stay is not decreased by the use of a CPM device and, depending on the hospital involved, the overall cost is not increased.
• Wound complications probably are not increased with the use of CPM, provided good technique is used in wound closure, and gradual increase in ROM occurs during the first 4 days postoperatively.

It is still not clear whether ROM is achieved faster and whether the prevalence of deep vein thrombosis (DVT) and analgesics use are decreased with CPM.

If ligament instability is present in the days immediately following the surgery, a postoperative knee brace is used which is initially adjusted to a 0- to 90-degree position. The brace functions to allow free movement in the 0- to 90-degree range, while preventing varus and valgus forces to the knee, and thus assists in maintaining the corrective alignment obtained in surgery.

Goals

• Prevent postoperative complications including DVT, infection, and pulmonary embolus.
• Reports of pain to be 5/10 or less.
• Minimize detrimental effects of immobilization.
• Patient to achieve an independent or supervised functional level for the following:
  • Transfers in and out of bed, on and off a commode, up and down from an appropriate chair (high or elevated).
  • Ambulation at a household level with an appropriate assistive device.
  • Stair negotiation of one or more steps, as dictated by home environment, with appropriate assistive device and with or without handrail.
  • Adherence to weight-bearing status.
• Active assistive ROM to be at 5–90 degrees of involved knee motion or better.
• Patient to achieve functional straight leg raise without extensor lag.
• Motor performance to be at 3/5 on manual muscle test.

Electrotherapeutic and Physical Modalities

Modalities to reduce pain and swelling (ice and elevation) are initiated as early as possible. With the physician's permission, electrical stimulation can be used for edema reduction, muscle reeducation, and pain control. The use of neuromuscular electrical stimulation (NMES) has been shown to reduce extensor lag and the length of stay in the acute care setting when used in conjunction with a CPM machine.

Hecht and colleagues compared the effectiveness of local applications of cold and heat in conjunction with exercise versus exercise alone on postsurgical pain of the knee. The application of cold with exercise was rated as providing significantly greater relief than the application of heat plus exercise or exercise alone, and swelling was also significantly decreased in the group that received the cold therapy. No other significant differences between groups were found.

Therapeutic Exercise and Home Program

Exercise encourages early enforcement of quadriceps activity and passive ROM, as well as reduction of joint effusion. The patient is instructed to perform sets of 10 repetitions of isometric contractions during every waking hour, focusing on breathing normally during these exercises. These exercises are usually initiated on the first or second postoperative day and include the following:

• Resistive exercises to the uninvolved extremities.
• Deep breathing exercises.
• Proper elevation and positioning of the involved lower extremity.
• Active assistive knee flexion and extension to the involved knee. If CPM is ordered, it is typically applied immediately after surgery in the recovery room to patient's tolerance, so as not to irritate the soft tissue response to the surgery. The patient is encouraged to remain on the unit for 10–12 hours each day, with gradual increases in both extension and flexion ranges as tolerated.
• Ankle pumps, quadriceps sets, gluteal sets, hamstring sets, heel slides.
• Straight leg raising.During the early days postoperatively, leg raises are limited to the supine and prone positions to prevent the varus and valgus forces associated with hip abduction and adduction in the initial healing phase. Cemented fixation allows for these movements at 2 weeks postsurgery. However, in uncemented knee replacements, hip abduction and adduction are not permitted until 4–6 weeks, pending sufficient bony ingrowth on radiographic examination.
• Seated knee extension.
• Standing knee flexion of the involved leg.

Functional Training

Functional training includes the following:

• Transfer training in and out of bed, from bed to and from chair, and to and from commode or elevated toilet seat.
• Gait training, including instruction on weight-bearing status, use of an assistive device, and stair negotiation. Ambulation on different levels can occur by the second or third day, if appropriate. The correct progression of weight bearing is crucial to the overall success of the joint replacement, and depends on the type of fixation and alignment. In patients with porous-coated prostheses, limited weight bearing is essential to allow for sufficient bony ingrowth into the prosthesis, and to prevent loosening of the appliance and premature failure of the surgical alignment. Full weight bearing is generally allowed at 6 weeks, based on a radiographic examination and the patient's body weight.

Manual Therapy

Manual therapy techniques include patellar mobilization and soft tissue techniques. Because unrestricted patellofemoral mobility is essential for normal knee motion, mediolateral and superior patellofemoral mobilizations are initiated as early as the second postoperative day.

The patient is discharged from the hospital to home or an extended care facility when medically stable. To be discharged to home, the patient should be able to demonstrate 80–90 degrees of active or active assisted knee motion, transfer supine to sit and sit to stand, ambulate 100 feet, and ascend and descend three steps or more, as the home environment dictates.

If functional independence is required before a patient returns home, the patient is typically transferred to an acute or subacute care setting. If adequate home care and safe transport are available, the patient is allowed to return home.

Home Care Phase (1–2 Weeks)

This phase typically involves a visit from a physical therapist for 3 days a week. A physical home care assessment usually occurs within 24 hours after hospital discharge.

During this phase, the role of the physical therapist is to address any safety concerns including moving or adjusting the height of furniture, removal of any throw rugs, review of sitting and sleeping positions, and progression of the home exercise program. Weight-bearing exercises are typically introduced at this time. These include seated heel raises , sit-to-stand exercises, mini-lunges (weight shifting), and mini-squats.

Specific transfers in the home and car are practiced. Gait training is advanced to crutches or cane, depending on the patient's balance. Once patients are no longer homebound, they begin outpatient physical therapy.

Phase 2: Outpatient (Weeks 3–6)

This phase typically involves three to eight physical therapy sessions.

Goals

• Patient to demonstrate functional independence with gait and an assistive device on level surfaces and stairs.
• Patient to normalize gait pattern as necessary.
• Patient to achieve independence with basic activities of daily living (ADLs). ADLs may cause pain at this time. The patient should be advised against overactivity.
• Active range of motion (AROM) of involved knee flexion to be at 110–125 degrees. This degree of knee flexion is necessary for successful stair negotiation and for sitting on a regular toilet seat.
• AROM of knee extension to be at 0 degrees to normalize gait.
• Motor performance to be at 4/5 for the involved extremity, demonstrated by single-leg half squat at 65% of body weight.
• Reports of pain to be 3/10 or less.

Electrotherapeutic and Physical Modalities

Electrical muscle stimulation is used in this phase of rehabilitation, with particular attention to the vastus medialis obliquus. Once full extension is achieved, NMES is applied throughout ROM and during multiple-angle isometrics including those angles at which the quadriceps appears to function less efficiently.In the more advanced stages of weight bearing, NMES is applied in the standing position to enforce strengthening of the quadriceps in the end range of extension, while incorporating proprioceptive training through the closed kinetic chain.

Therapeutic Exercise and Home Program

The exercise program during this phase can include the following:

• Aerobic conditioning (stationary cycling, upper body ergonometer). Through seat adjustment on the stationary bicycle, emphasis can be placed on either flexion or extension, maintaining a comfortable, slow cadence so as not to traumatize the joint at its end range while gaining the benefit of prolonged stretch and high repetition. The reciprocal pattern of bicycling incorporates multiple joint motions and strengthening through a functional pattern of movement. Because most of this patient population has had a limited activity level since prior to surgery, it is not long before this cycling program becomes an aerobic activity, and therefore affects cardiovascular endurance as well.
• Aquatic therapy (deep-water jog, squats, straight leg raises, step-up exercises), if available.
• Isotonic exercises with ankle weights or surgical tubing. These exercises include knee extension, knee flexion, straight leg raising in all four planes (flexion, extension, adduction, abduction), and bridging.
• Side-lying hip external rotation . The patient lies on the uninvolved side with the shoulders and hips perpendicular to the table and the knees flexed to about 45 degrees. The patient lifts the top knee toward the ceiling, maintaining the pelvic position and contact of the feet.
• Flexibility exercises. A basic flexibility program is introduced, which includes stretches of those two-joint muscle groups that cross the knee joint, in particular, the hamstrings, gastrocnemius, and quadriceps.
• Weight-bearing exercises including partial lunges, leg press, bilateral heel raises, wall slides, and partial squats.

Neuromuscular Training

The following exercises may be performed based on the goals of the intervention:

• Balance-and-reach exercises.
• Backward walking.
• BAPS (biomechanical ankles platform system).
• Toe-heel walking.
• Side-stepping.
• Mini-trampoline exercises.
• Single limb balancing on the involved leg.

Manual Therapy

Manual therapy during this phase includes joint mobilizations to the patella, as appropriate, and soft tissue techniques to stretch the surrounding musculature.

Phase 3 (Weeks 7–12)

This phase typically involves 3–12 physical therapy sessions.

Goals

• Patient to achieve independence and pain-free motion with all ADLs.
• Patient to have independent, normal gait pattern with single-point cane over all surfaces.
• Patient to achieve return to employment or previous hobbies as indicated.
• AROM to be at 0–115 degrees.
• Motor performance to be at 5–/5 on manual muscle testing or equal to the uninvolved leg.
• Reports of pain to be at 2/10 or less.

Therapeutic Exercise

• Emphasis is placed on remaining muscle performance and ROM deficits.
• Self-stretching exercises are performed.
• Gait training is advanced to use of a single-point cane on stairs and all surfaces.
• Endurance activities in this phase shift to a progressive walking program. The program begins with 8- to 10-minute walking sessions, progressing to 60-minute walk as tolerated. The level of activity achieved after a TKA is dependent on a number of factors. The most significant consideration for patients and orthopaedic surgeons in considering athletic activity after knee replacement is wear at the weight-bearing surface.

Neuromuscular Retraining

Various techniques and changes in direction can be applied to lateral step-ups to make the exercise more difficult and challenging to the proprioceptive system.

Higher levels of balance board activities are introduced. Walking activities may be progressed to include side-stepping and quick changes in direction.

Manual Therapy

Manual therapy techniques include

• joint mobilization to the patella as indicated
• passive stretching of the two joint muscles of the knee and hip (gastrocnemius, hamstrings, rectus femoris)

Outcomes

Traditionally, clinical rating scores have been used to assess results following TKA. These rating systems typically aggregate weighted scores for pain, ROM, stability, alignment, and functional ability.

The use of patient-reported outcome measures for assessing the outcomes of TKA has been emphasized in the orthopaedic literature over the past 10 years. Patient self-reported measures of outcome, such as the WOMAC and the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), have now been accepted by the orthopaedic community.

Both the condition-specific WOMAC and the generic SF-36 capture the improvement in pain in patients undergoing comprehensive inpatient rehabilitation intervention sufficiently well.

Mark Dutton, PT,Orthopaedic Examination, Evaluation, and Intervention 2nd edition McGraw-Hill 2008  ISBN: 0071474013 

http://www.acta-ortho.gr/v53t3_2.html

http://www.maitrise-orthop.com/corpusmaitri/orthopaedic/92_reignier/regnierus.shtml

IMPINGEMENT SYNDROME AND ROTATOR CUFF TEAR

General


• Impingement syndrome (Figure 4–18)
– Most likely the most common cause of shoulder pain
– A narrowing of the subacromial space causing compression and inflammation of the subacromial bursa, biceps tendon, and rotator cuff (most often involving the supraspinatus tendon).
– Impingement of the tendon, most commonly the supraspinatus, under the acromion and the greater tuberosity occurs with arm abduction and internal rotation.
– Impingement syndrome may progress to a rotator cuff tear (complete or partial)
– Stages of subacromial impingement syndrome
Stage 1: Edema or hemorrhage—reversible (age < 25)
Stage 2: Fibrosis and tendonitis (ages 25–40)
 Stage 3: Acromioclavicular spur and rotator cuff tear (Age > 40)

• Rotator cuff tear

Etiology

– The rotator cuff is composed of four muscles (Figure 4–19):

1. Supraspinatus

2. Infraspinatus

3. Teres minor

4. Subscapularis

– These muscles form a cover around the head of the humerus whose function is to rotate the arm and stabilize the humeral head against the glenoid.

– Rotator cuff tears occur primarily in the supraspinatus tendon which is weakened as a result of many factors including injury, poor blood supply to the tendon, and subacromial impingement.

– May be as a result of direct trauma or an end result from chronic impingement. This injury rarely affects people < 40 years of age.

Acromion Morphology and Its Association to Rotator Cuff Tears (Figure 4–20)

The anatomic shape of the patient’s acromion has been linked with occurrence rates of rotator cuff tears patients with curved or hooked acromions have a higher risk of rotator cuff tears.

• Type I → flat

• Type II → curved

• Type III → hooked

Clinical

• Pain during range of motion, specifically in repetitive overhead activities, such as:

– Throwing a baseball

– Swimming (occurs at the catch phase of the overhead swimming stroke)

Mechanism: flexion, abduction, internal rotation.

More common strokes: freestyle, backstroke, and butterfly.

Less common stroke: breast stroke.

• Supraspinatus and biceps tendons are commonly affected secondary to their location under the acromion.

– Patients may feel crepitus, clicking, catching on overhead activities.

– Pain may be referred anywhere along the deltoid musculature.

– Weakness in forward flexion, abduction, and internal rotation indicating impingement

(Hawkins sign).

– Inability to initiate abduction may indicate a rotator cuff tear.

– Pain may be nocturnal. Patients often report having difficulty sleeping on the affected side.

– Tenderness over the greater tuberosity or inferior to the acromion on palpation.

– Atrophy of the involved muscle resulting in a gross deformity at the respective area, usually seen in chronic tears.

Provocative Tests

• Impingement test

– Neer’s impingement sign (Figure 4–21)

Stabilize the scapula and passively flex the arm forward greater than 90° eliciting pain. Pain indicates the supraspinatus tendon is compressing between the acromion and greater tuberosity.

– Hawkins Impingement Sign (Figure 4–22)

Stabilize the scapula and passively forward flex (to 90°) the internally rotated arm eliciting pain.

A positive test indicates the supraspinatus tendon is compressing against the coracoacromial ligament.

– Painful arc sign

Abducting the arm with pain occurring roughly between 60–120°

• Rotator cuff tests

– Supraspinatus test

Pain and weakness with arm flexion abduction and internal rotation (thumb pointed down)

With abduction the humerus will naturally externally rotate. In assessing the integrity of the supraspinatus, the patient should internally rotate the humerus, forcing the greater tuberosity under the acromion. In this position, the maximum amount of abduction is to 120°.

– Drop arm test

The arm is passively abducted to 90° and internally rotated. The patient is unable to maintain the arm in abduction with or without a force applied. Initially the deltoid will assist in abduction but fails quickly.

This indicates a complete tear of the cuff.

Imaging

• Plain films (AP)

– Impingement

Cystic changes in the greater tuberosity

– Chronic rotator cuff tear

Superior migration of the proximal humerus.

Flattening of the greater tuberosity.

Subacromial sclerosis.

• Supraspinatus outlet view (15° caudal tilt for a transcapular Y view) (Figure 4–23)

– Assess acromion morphology

• MRI is the gold standard to evaluate the integrity of the rotator cuff

– Full thickness tears and partial tears can be delineated

– Gadolinium may be added to evaluate the labrum

• Arthrogram

– Beneficial in assessing full thickness tears but unable to delineate the size of the tear or partial tears; should not be used in patients who have allergies to dyes.

• Ultrasound: Operator dependent

Treatment

Impingement, chronic-partial and full tears

• Conservative: Rehabilitation

– Acute phase (up to 4 weeks)

Relative rest: Avoid any activity that aggravates the symptoms.

Reduce pain and inflammation.

Modalities: Ultrasound iontophoresis.

Reestablish nonpainful and scapulohumeral range of motion.

Retard muscle atrophy of the entire upper extremity.

– Recovery phase (months) (up to 6 months)

Improve upper extremity range of motion and proprioception.

Full pain-free ROM.

Improve rotator cuff (supraspinatus) and scapular stabilizers.

Assess single planes of motion in activity related exercises.

– Functional phase

Continue strengthening increasing power and endurance.

Activity-specific training

Corticosteroid injection: Only up to three yearly

May weaken the collagen tissue leading to more microtrauma

• Surgical

– Indications

Full thickness or partial tears that fail conservative treatment

Reduction or elimination of impingement pain is the primary indication for surgical repair in chronic rotator cuff tears. The patient should be made aware that restoration of abduction is less predictable than relief of pain.

– Partial tears (< 40% thickness)

Procedure: Partial anterior acromioplasty and coracoacromial ligament lysis (CAL)

– Partial tears (> 40% thickness)

Excise and repair

– Acute rotator cuff tears (i.e., athletes/trauma)

Statistics show that surgical repair of an acute tear within the first three weeks results in significantly better overall function than later reconstruction.

Physical medicine and rehabilitation board review / by Sara J.Cuccurullo, editor.Demos Medical Publishing, 386 Park Avenue South, New York, New York 10016. 2004. ISBN 1-888799-45-5

Low-back pain due to disk herniation

The subject of this section is disk herniation without radicular compression. It is essential to know when disk herniation should be suspected in simple low-back pain. The conditions described thus far have been functional disorders. Here, however, we are faced with a defined pathological lesion with a correspondingly serious prognosis. It must be remembered that many instances of disk herniation are completely devoid of clinical relevance, and for this reason the prognosis is favorable even with conservative therapy. At the same time, dysfunctions play an important role here.



Symptoms
If we discount acute attacks, the clinical course as a rule is more severe than in straightforward functional disorders, that is to say attacks last longer and the condition has a greater tendency to relapse.
Coughing and sneezing are generally very painful. The posture that is particularly difficult for patients to manage is bending forward (even slightly), as over a wash basin, because in this position contraction
of the erector spinae is maximal and therefore the pressure on the disk is at its greatest. The ‘painful arc’ described by Cyriax (1977, 1978) also generally manifests itself in this position. Pain when turning over in bed and when getting up is also highly characteristic.


Clinical signs

In acute cases there is a characteristic antalgic (or relieving) posture that is also adopted in response to radicular pain. The most typical antalgic pattern is lumbar kyphosis with the pelvis displaced toward the side of the lesion (and deviation of the trunk to the opposite side; see Figure 1).





Figure 1 • Typical antalgic posture in acute intervertebral
disk herniation.







Anteflexion while standing is generally severely limited and the straight-leg raising test is positive
(except in lesions at L3/L4 where the femoral nerve stretch test is positive). All movement that is
at odds with the antalgic posture is painful. There need not be any movement restriction in the segment affected by disk herniation. When movement restriction is present simultaneously, springing of the lumbar spine continues to elicit pain even after the restriction has been released. Conversely, an (experimental) traction test may bring marked pain relief. In the more chronic stage, anteflexion is limited while standing, but normal when the patient is seated (with knees flexed). Another very typical sign is the painful arc described by Cyriax (1977, 1978) (see Section 4.6.1). Here, too, the straightleg raising test and the femoral nerve stretch test in segment L3/L4 are positive, much more so than when there is only joint restriction. A most valuable diagnostic sign is pain on springing the lumbar spine, irrespective of whether restriction is present or not.



Therapy
Manual traction taking account of antalgic posture may be attempted in the acute stage. In other
words, if the antalgic posture is in kyphosis, then traction is performed with the patient supine over
the practitioner’s knee, but if the antalgic posture is in lordosis, then traction is performed with the
patient lying prone. If traction is well tolerated it may procure immediate relief. Counterstrain to
exaggerate the antalgic posture is also highly effective. This might be termed ‘manipulative first aid.’ If these techniques fail to bring immediate relief, epidural anesthesia and bed rest in the antalgic posture should be considered, as should analgesic medication. However, bed rest should be kept as brief as possible because energetic (‘aggressive’) therapy in the acute stage is the most important step in preventing chronicity. Traction may also be helpful in the chronic stage, provided that the patient finds it agreeable and improvement is detected afterward. In every instance it is important to proceed in a manner that is consistent with the clinical findings, and this approach presupposes a fresh examination at every follow-up visit. In this process, chain reaction patterns should be sought in order to shed light on the pathogenesis. Current knowledge indicates that the commonest causes are to be found in the deep stabilizer system (in conjunction with faulty breathing), the feet, faulty movement patterns, active scars, movement restrictions, and TrPs in the key region as well as the fascia.

No less important are general measures: these include avoiding situations that routinely trigger
recurrences, and protecting the lumbar region against chill after perspiring.


Lewitt Karel. Manipulative Therapy, Musculoskeletal Medicine. 1st edition published in English © 2010, Elsevier Limited. ISBN: 978-0-7020-3056-7

Patellofemoral syndrome

Synonyms : Anterior knee pain, Chondromalacia patellae, Patellofemoral arthralgia, Patellar pain,  Maltracking, Patellalgia.


DEFINITION


Patellofemoral Syndrome, is the most common ailment involving the knee in both athletic and nonathletic population. In sports medicine clinics, 25% of patients complaining of knee pain are diagnosed with this syndrome, and it affects women twice as often as men. Despite the common occurance of this disorder, there is no clear evidence of the definition, etiology, and pathophysiology. The most common theory is that the syndrome is an overuse injury from repetitive overload at the patellofemoral joint. This increased  stress results in[hysical and biomechanical changes of the patellofemoral joint. The literature has focused on identification of  risk factors leading to altered biomechanics to produce maltracking of the patella in the femoral trochlear groove and thus stress at the patellofemoral joint. Possible pain generators include the subchondrial bone, retinacular, capsule, and synovial membrane. Historically, the histologic diagnosis of chondromalacia had been associated with patellofemoral syndrome. However, chcondromalacia is poorly associated with the incidence of patellofemoral syndrome.


NORMAL KINESIOLOGY OF THE KNEE
Forces acting on knee

Isolating the knee joint as it is possible to see in the figure can show that the forces that acting on patellofemoral joint (PFJ) on extension of the knee are the quadriceps muscular force (FQ), the force is transmitted to the patellar tendon (FPT) and the reaction force generated on the PFJ (FPFJR). So the FPFJR increases proportionally with the knee flexion, not only increases with knee flexion due to the resultant force rise but also because of the flexor lever arm, which requires a quadriceps response, increases in length.
As a general rule it is not advisable to bend the knees excessively, when they are under strain. Additionally it seems now very logic that losing weight obese patients can improve their conditions since the FPFJR is decreased, since it has less weight to support.



SYMPTOMS


The patient with patellofemoral syndrome will complain of diffuse, vague ache of insidious onset. The anterior knee is the most common location for pain, but some patients describe posterior knee discomfort in the popliteal fossa. The discomfort is aggravated by prolonged sitting with knees flexed, as well as on ascending or descending of stairs and squating because this positions place the greates force on the patellofemoral joint. The patient may also experience pseudolocking when the knee momentariy locks in an extended position.


PHYSICAL EXAMINATION

The examination focuses on identification of risk factors that contribute to malalignment and rules out other pathologic processes associated with anterior knee pain. Tenderness to palpation at the medial and lateral borders of the patella may be beneficial. A minimal effusion may also be present. The results of manual testing for intrarticular disease, such as the Lachman (Anterior cruciate ligament) and McMurray (menisci) maneuvers, will be negative.
The presence of femoral anteversion, tibial internal rotation, excessive pronationat the foot, increased Q angle, and inflexibility of the hip flexors, quadriceps, iliotibial band, and gastrocnemius-soleus should be determined.
The patella position ( baja or alta, squinting or grasshopper) should also be assessed with patient sitting and standing. Each of these factors has either a direct or an indirect influence on the tracking of the patella with the femur.

The Q angle is the intersection of a line from the anterior superior iliac spine to the patella with a line from the tibial tubercle to the patella. This angle is typically less than 15 degrees in men and less than 20 degrees in women. An increased Q angle is associated with increased femoral anteversion and thus patellofemoral joint torsion. However a consensus on the importance of an increased Q angle is lacking. Tight hip flexors quadriceps, hamstrings and gastrocnemius-soleus will increase knee flexion and thus patellofemoral joint reaction force. A tight iliotibial band will increase the lateral pull of the patella through the lateral retinacular fibers. It is necessary to assess each of these components in the lower extremity kinetic chain to prescribe a specific physical  therapy  program for each individual.


FUNCTIONAL LIMITATIONS


The patient with patellofemoral syndrome will avoid activities that provoke the dicomfort initially, such as stair climbing. Prolonged sitting in a car may be difficult. In chronic, progressive cases, ambulation may be enough to incite the pain, making all activities of daily living difficult.


DIAGNOSTIC TESTING


Patellofemoral syndrome is a clinical diagnosis. Plain films may be used to evaluate Q angle and patella alta or baja. Advanced imaging such as MRI is reserved for persistent cases that do not respond to conservative care to rule out intra-articular disease. Bone scintigrams revealed diffuse uptake in the patellofemoral joint in 50% of patients diagnosed with patellofemoral syndrome.


TREATMENT
Initial
As in other overuse injuries, the initial treatment focuses on decreasing pain. Icing is beneficial, particularly after activities. NSAIDS may be used in a judicious manner. Relative rest with non-weight bearing activities may also be beneficial. A neoprene knee sleeve with patella cutout is helpfull to increase proprioceptive feedback. McConnel's taping method can be used during the acute phase to reduce pain and to increase tolerance of the therapeutic exercise program.
Patella bracing was shown to reduce pain and to improve  function in patients with patellofemoral syndrome but no more succesfully than therapeutic exercise.


Rehabilitation
With no consensus on the etiology ad pathophysiology of patellofemoral syndrome, numerous treatment protocols and therapies have been used in the literature. Nevertheless most patients respond to a directed rehabilitation approach with therapeutic exercise. The RHB program should address deficiencies in strength, flexibility, and proprioception. Strength training can be achieved with both open and closed kinetic chain exercises. Open kinetic chain exercises occur when the distal link, the foot, is allowed to move freely in space, During closed kinetic chain exercises, the foot remains in contact with the ground, resulting in a multiarticular closed chain kinetic exercise.
An example of an open kinetic chain exercise is a leg press extension. A closed kinetic chain exercise is also less stressful than open chain exercises at the patellofemoral joint in the functional range of 0 to 45 degrees of knee flexion.


These exercises can be performed in multiple planes in a ''functional'' rehabilitation program as the picture next to the text shows.
This may entail having tha patient perform a lunge (A) in the coronal, saggital and transvers planes, simulating positions applied during daily activities. These exercises can also stress the patient's balance by performance of the lunges with eyes closed. Through this functional or skill training, the patient is being prepared for all functional tasks by achieving efficient nerve muscle interactions.





Many studies have focused on selective strengthening  of the vastus medialis obliquus as a dynamic medial stabilizer on the patella. Selective VMO strengthening may be achieved with combined hip adductions because the fibers of the VMO originate on the adductor magnus tendon and to a lesser extent , the adductor longus. However, attemts at proving isolated recruitment of the VMO in relation to the vastus lateralis have failed. Nevertheless, quadriceps strengthening in general should be incorporated in the rehabilitation program through closed kinetic chain and functional exercises.




Procedures
Injection are not indicated because this is primarily a maltracking phenomenon without a clear consesus on the pain generator.
Surgery is rarely indicated, and directed rehabilitation program is often successful. However, several techniques have been illustrated in the literature. These include lateral retinacular release to decrease the latera force, proximal and distal realignment procedures, and elevation of the tibial tubercle.


POTENTIAL DISEASE COMPLICATIONS


Persistent chronic cases of anterior knee pain may show progressive degenerative changes at the patellofemoral joint, such as severe (grade IV) chondromalacia patellae.


POTENTIAL TREATMENT COMPLICATIONS


Over compensation for the malaligment may occur with surgical techniques such as the laterar retinacular release. The surgeon may lyse too many fibers, leading to increased medial tracking. Many of the realignment procedures should also be reserved for the skeletally mature patient.






Frontera R.Walter, Silver K.Julie,Rizzo D. Thomas, Essentials of Physical Medicine and Rehabilitation Musculoskeletal Disorders, Pain, and Rehabilitation  2nd edition 2008 Saunders Elsevier, ISBN:9781416040071


Kapandji I.A, Churchill Livingstone. The physiology of joints vol.2 Lower Limb. Paris: Librairie, Maloine,Paris, 1987.0443036187


Braddom L.Randall, Physical medicine & Rehabilitation fourth edition,2011, Saunders, Elsevier, ISBN:9781437708844