Patellofemoral Pain Syndrome (PFPS)

Normal Anatomy

 The patellofemoral joint is the joint between the patella and the trochlea of the femur  Hyaline cartilage is present on the articulating surfaces of the patella and trochlea  Convex surface of patella articulates with convex surface of trochlea  Patella is sesamoid bone, embedded within quadriceps and patella tendon  Patella glides superiorly during knee extension and inferiorly during knee flexion  Lateral femoral condyle acts as bony block to limit lateral motion during knee flexion  Retinaculum passively stabilises patella  Associated soft tissue structures commonly affected in PFPS: o Anterior synovial tissues o Anterior knee joint capsule o Suprapatellar plica o Fat pad o Bursae o Medial patellofemoral ligament o Retinaculum o Quadriceps/patella tendon o ITB

Pathology  Pain arising from the structures in and around the patellofemoral joint Pathophysiology  Loss of osseous or peripatellar soft tissue homeostasis due to trauma, overload or high frequency of load to bone/soft tissues  Potential neural involvement  Excessive pressure of lateral structures stimulates release of substances that produce growth of new nerves and blood vessels e.g. Substance P, Vascular Endothelial Growth Factor (VEGF)  May be similar mechanism to tendinopathy  Anterior synovial tissues, retinaculum, fat pad and capsules – severe localised pain  Capsular margins, femoral condyles – poorly localised moderate pain

1 Mechanism of Injury

Traumatic  Compression – falling onto knee, impact of patella into trochlea  Twisting – subluxation/dislocation of patella Overuse  Biomechanical overload  Biological overload (i.e not allowing tissue to recover)

Classification

1. Patellar Compression Syndrome a. Excessive Lateral Pressure Syndrome (more details below) b. Global Patellar Pressure Syndrome (more details below) 2. Patellar Instability a. Chronic Patellar Subluxation b. Acute Patellar Dislocation c. Recurrent Patellar Dislocation 3. Biomechanical Dysfunction (more details below) 4. Direct Patellar Trauma a. Articular Cartilage Lesion (isolated) b. Fracture c. Fracture/dislocation d. Articular Cartilage Lesion with associated malalignment 5. Soft Tissue Lesions a. Suprapatella Plica b. Fat Pad Syndrome c. Medial Patellomfemoral Ligament Pain d. Iliotibial Band Friction Syndrome e. Bursitis 6. Overuse Syndromes a. Tendinitis (tendinopathy) b. Apophysitis 7. Osteochondritis Dessicans 8. Neurologic Disorders a. Reflex Sympathetic Dystrophy b. Sympathetically maintained pain

Patellar Compression Syndrome - Excessive Lateral Pressure Syndrome

 Patella is squeezed by surrounding soft tissue  If surrounding soft tissue is ‘tight’ the patella looses its mobility  Excessive pressure of the lateral structures can cause lateral retinacular pain  Pain can occasionally be medially as the structures are on constant stretch

2  Can eventually lead to degeneration of the lateral facet of the patella  Restriction in medial glide of patella resulting in lateral tilt Patellar Compression Syndrome - Global Patellar Pressure Syndrome

 Both Medial and Lateral retinaculum are tight  Develops due to fibrosis of tissues following trauma or immobilization  Global restriction in patella range of movement  Knee pain is reported globally around the patella

Biomechanical Dysfunction

 Biomechanical dysfunction at the low back, hip, tibia and ankle can change the kinematics of the knee  This alters the patellofemoral joint stress and can cause pain  Excessive lateral pressure syndrome can occur because of biomechanical dysfunctions  Management varies depending on classification/cause

 See Wilk et al., 1998 for more information on the management of each classification

Examination Subjective  Insidious onset (generally, global patella compression syndrome is usually traumatic)  History of overloading tissues (increase in activity/training duration, intensity, frequency and/or inadequate rest)  Ill defined ache localized anterior knee  Sharp pain occasionally  Aggs: squatting, running, walking down slopes, sitting for long periods (theatre goers knee), stairs  Giving way o Pain inhibition of quads o Patella laterally dislocating

Objective  Pain on palpation patella facets  Restricted ankle dorsiflexion  Continued pronation during gait  Restricted hip flexion/abduction/internal rotation  Restricted tibial internal rotation  Reduced quadriceps strength  Reduced hip extension/abduction strength  Painful squatting, stepping, lunge

3  Valgus collapse at knee  Need to gain overview of the entire lower limb kinetic chain  Review painful functional movements i.e squatting, lunging, stairs, etc.  Establish at what point in the movement reproduces pain.  Assess whether this can this be improved with adjustments? e.g by correcting knee valgus

Special Tests  Specific tests are not useful (Nunes et al., 2013)  Patella tracking and tilt is unreliable (Song et al., 2011)  Assessing medio-lateral patellar position ONLY reliable and valid test available (Smith et al., 2009)

Further Investigations  Bone scintigraphy - can possibly detect changes in osseous metabolism.  X-ray – not often useful, except if bony trauma  MRI – useful to guide treatment only in certain cases e.g. joint effusion  Ultrasound – can possibly detect soft tissue lesions  Further investigation is commonly ineffective at facilitating diagnosis or guiding treatment.  Findings on investigation do not necessarily correlate with symptoms.

Management  Should be multimodal  Mixture of manual therapy AND correct rehabilitation  Control of overloading to allow biological tissue to repair/regain homeostasis  Ensure adequate time for recovery between training sessions  Surgery should not be considered as lateral release has POOR outcomes Conservative Goal of therapy is to:  Reduce overload to tissues, but maintaining sufficient load to prevent deloading  Promote healing/restoration of homeostasis  Restore normal biomechanics and movement  Improve neuromuscular control and proprioception  Prepare for return to sport/full function o Reduce Pain and Inflammation . Massage . Ice . NSAID’s . Appropriate loading . Taping . Orthotics o Restore Normal Range of Movement . Soft Tissue Low Back, Hip, Knee, Ankle  Soft Tissue techniques such as massage, foam rolling,

4 stretching dry needling etc . Joints Low Back, Hip, Knee, Ankle  Joint Mobilisations, Manipulations o Restore Normal Motor Control and Strength . Quads in a pain free range and minimum PFJ stress  Leg press 0-45° knee flexion, leg extension 45-90° knee flexion, gradually increasing ROM . Glutes  Hip external rotation and abduction o Address further biomechanical dysfuctions . Movement Patterns  Squat and single leg squat patterns  FMS . Gait assessment and re-education  Increase stride width . Footwear  Orthotics  Bearfoot running o Restore Dynamic Stability . Exercises that challenge the stability of the entire lower limb kinetic chain in a pain free range o Return to sport/activity specific exercise Surgical  Lateral release – poor outcomes References (Barton et al., 2013; Collado & Fredericson, 2010; Collins et al., 2013; Dye, 2001; Fagan & Delahunt, 2008; Fukuda et al., 2010; Lee et al., 2003; Nakagawa et al., 2012; Nunes et al., 2013; Peters & Tyson, 2013; Powers, 2003; Salsich et al., 2012; Schoots et al., 2013; Selfe et al., 2013; Smith et al., 2009; Vicenzino et al., 2010; Wilk et al., 1998) Barton CJ, Lack S, Malliaras P, Morrissey D. Gluteal muscle activity and patellofemoral pain syndrome: a systematic review. Br J Sports Med 2013; 47(4): 207-14. Collado H, Fredericson M. Patellofemoral pain syndrome. Clin Sports Med 2010; 29(3): 379- 98. Collins NJ, Bierma-Zeinstra SM, Crossley KM, van Linschoten RL, Vicenzino B, van Middelkoop M. Prognostic factors for patellofemoral pain: a multicentre observational analysis. Br J Sports Med 2013; 47(4): 227-33. Dye SF. Patellofemoral Pain Current Concepts: An Overview. Sports Med Arthrosc 2001; 9(4): 264-72. Fagan V, Delahunt E. Patellofemoral pain syndrome: a review on the associated neuromuscular deficits and current treatment options. Br J Sports Med 2008; 42(10): 789- 95. Fukuda TY, Rossetto FM, Magalhaes E, Bryk FF, Lucareli PR, de Almeida Aparecida Carvalho N. Short-term effects of hip abductors and lateral rotators strengthening in females with patellofemoral pain syndrome: a randomized controlled clinical trial. J Orthop Sports Phys Ther 2010; 40(11): 736-42. Lee TQ, Morris G, Csintalan RP. The influence of tibial and femoral rotation on patellofemoral contact area and pressure. J Orthop Sports Phys Ther 2003; 33(11): 686-93.

5 Nakagawa TH, Moriya ET, Maciel CD, Serrao FV. Trunk, pelvis, hip, and knee kinematics, hip strength, and gluteal muscle activation during a single-leg squat in males and females with and without patellofemoral pain syndrome. J Orthop Sports Phys Ther 2012; 42(6): 491-501. Nunes GS, Stapait EL, Kirsten MH, de Noronha M, Santos GM. Clinical test for diagnosis of patellofemoral pain syndrome: Systematic review with meta-analysis. Phys Ther Sport 2013; 14(1): 54-9. Peters JS, Tyson NL. Proximal exercises are effective in treating patellofemoral pain syndrome: a systematic review. Int J Sports Phys Ther 2013; 8(5): 689-700. Powers CM. The influence of altered lower-extremity kinematics on patellofemoral joint dysfunction: a theoretical perspective. J Orthop Sports Phys Ther 2003; 33(11): 639-46. Salsich GB, Graci V, Maxam DE. The effects of movement pattern modification on lower extremity kinematics and pain in women with patellofemoral pain. J Orthop Sports Phys Ther 2012; 42(12): 1017-24. Schoots EJ, Tak IJ, Veenstra BJ, Krebbers YM, Bax JG. Ultrasound characteristics of the lateral retinaculum in 10 patients with patellofemoral pain syndrome compared to healthy controls. J Bodyw Mov Ther 2013; 17(4): 523-9. Selfe J, Callaghan M, Witvrouw E, et al. Targeted interventions for patellofemoral pain syndrome (TIPPS): classification of clinical subgroups. BMJ Open 2013; 3(9). Smith TO, Davies L, Donell ST. The reliability and validity of assessing medio-lateral patellar position: a systematic review. Man Ther 2009; 14(4): 355-62. Vicenzino B, Collins N, Cleland J, McPoil T. A clinical prediction rule for identifying patients with patellofemoral pain who are likely to benefit from foot orthoses: a preliminary determination. Br J Sports Med 2010; 44(12): 862-6. Wilk KE, Davies GJ, Mangine RE, Malone TR. Patellofemoral disorders: a classification system and clinical guidelines for nonoperative rehabilitation. J Orthop Sports Phys Ther 1998; 28(5): 307-22.

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