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