Physiotherapy Management of Patellofemoral Pain Syndrome- Research Evidence

In my recent post I briefly reviewed the components of Evidence Based Practice (EBP). As we saw, Research Based Evidence is one component of EBP.

Subsequent to the EBP post, I plan to regularly post information in relation to the Research Evidence Base for various conditions. Over time I will then revisit each topic over time and update them accordingly with new research evidence.

This posts topic is Physiotherapy Management of Patellofemoral Pain Syndrome – Research Evidence.

Clinical Features of Patellofemoral Pain

Crossley et al (2012)

• Non-specific or vague pain. 
• Pain may be medial, lateral of infra patella.
• Pain aggravated by activities that load the patellofemoral joint (e.g. running, steps/stairs, hills).
• VMO:
  • wasting may, or may not, be present.
• Areas of potential tenderness:
  • medial and/or lateral patella facets.
  • infrapatella region.
  • may have no localised tenderness due to the area not be accessible to palpation.
• Swelling:
  • May have a small effusion.
• Clicks, clunks and/or crepitus under the patella can occur.
• Reports of “giving away” can occur due to subluxation or quadriceps inhibition.
• Knee range of motion usually normal.
• Quadriceps contraction in extension usually not painful.
• Patella mobility:
  • May be restricted in any direction.
• Functional testing:
  • Squats, stairs may aggravate.
  • Patella taping/medial glide should decrease pain.

Diagnostic Tests for Patellofemoral Pain

What about our “Diagnostic Tests“. Are they reliable and worthwhile? Some of the common tests being:

• Patella tracking
• Patella apprehension
• Compression test
• Medial/lateral palpation
• Clarke sign
• Patella flexion test
• Active instability test
• Pain during squatting
• Pain during stair climbing
• Pain during prolonged sitting
• Waldron test
• Eccentric step test

Cook et al (2012)

• A majority of the studies that have investigated diagnostic accuracy of clinical tests for PFPS demonstrate notable design or reporting biases, and at this stage, determining the best tests for diagnosis of PFPS is still difficult.

Nunes et al (2013)

• Due to the multifactorial etiology of PFPS, a number of tests have been developed for its diagnosis.
• This review found no PFPS test with diagnostic consistency, which thus prohibits inferences about the best test to use.
• Future studies should focus on or address sample homogeneity and test standardization so that new systematic reviews with meta-analysis can more clearly determine the tests’ accuracy in diagnosing PFPS.

Fredericson and Yoon (2006)

• An extensive search of the literature revealed no single gold-standard test maneuver for that disorder, and the reliability of the maneuvers described was generally low or untested.
• An abnormal Q-angle, generalized ligamentous laxity, hypomobile or hypermobile tenderness of the lateral patellar retinaculum, patellar tilt or mediolateral displacement, decreased flexibility of the iliotibial band and quadriceps, and quadriceps, hip abductor, and external rotator weakness were most often correlated with patellofemoral pain syndrome.

Factors that May Predispose to Patellofemoral Pain.

Davis and Powers (2010)

• Research review/summary
• Pain is a subjective measure and the importance of psychological state cannot be understated.
• Maltracking in patients with patellofemoral pain syndrome has been found in some studies, but not in others.
• There is a large amount of inter-subject variability in patellofemoral joint kinematics.
• Modeling and cadaveric studies have shown that the vastus medialis oblique plays an important role as a medial stabilizer of the patella.
• While impaired VMO function has been implicated in PFPS, this finding has not been consistent across all studies.
• Evidence suggests that abnormal femur motion may contribute to altered patellofemoral joint kinematics as opposed to abnormal patella motion.
• A more lateral roll over pattern as measured using plantar pressure has been reported to be associated with PFPS development in military recruits. Because most were males, this may suggest a predominant gait pattern for this gender.
• Individuals with PFPS have been reported to strike the ground with increased rearfoot eversion during walking and running.
• Consistent with prospective findings, it has been reported that individuals with PFPS may possess increased mid-foot mobility when moving from non-weight bearing to static relaxed stance, and when moving from a weight bearing subtalar joint neutral to static relaxed stance.
• Evidence suggests that patients with PFPS demonstrate altered hip kinematics in the frontal and transverse planes during various tasks.
• Kinematic changes are more likely to be seen during more demanding tasks such as a single-limb squat, running, single-limb jumping, and single-limb drop landing.
• Subjects with PFPS may use compensatory strategies to avoid faulty kinematics during less demanding tasks.
• Results from cadaveric and magnetic resonance imaging studies have shown that excessive femoral internal rotation increases lateral patella tracking and patellofemoral joint stress.
• Healthy females demonstrate hip abduction and external rotation weakness compared to healthy males. Females with PFPS demonstrate even greater hip weakness compared with healthy females.
• Healthy females demonstrate greater hip adduction than healthy males during functional tasks, and females with PFPS demonstrate even greater hip adduction compared with healthy females.
• There is prospective evidence that runners who go on to develop PFPS have increased hip adduction and internal rotation.
• There is some evidence that suggests that individuals with PFPS have delayed gluteus medius activity relative to the vastii muscles during stair-stepping tasks.

Lankhorst et al (2012)

• Systematic review
• Conclusions/Results:
  •  Pooled data showed a larger Q-angle, sulcus angle and patellar tilt angle, less hip abduction strength, lower knee extension peak torque and less hip external rotation strength in PFPS patients compared to controls.
  • Foot arch height index and congruence angle were not associated with PFPS.

Barton et al (2009)

• Systematic review
• Reductions in gait velocity were indicated during walking, ramp negotiation, and stair negotiation in individuals with PFPS. Findings indicated:
  • delayed timing of peak rearfoot eversion and increased rearfoot eversion at heel strike transient during walking
  • delayed timing of peak rearfoot eversion,
  • increased rearfoot eversion at heel strike
  • reduced rearfoot eversion range
  • greater knee external rotation at peak knee extension moment
  • greater hip adduction during running in individuals with PFPS.

Prins and van der Wuff (2009)

• Systematic review
• Strong evidence was found for a deficit in:
  • hip external rotation, abduction and extension strength
• Moderate evidence found for a deficit in:
  • hip flexion and internal rotation strength
• No evidence for a deficit in hip adduction strength compared with healthy controls
• Moderate evidence was found for a decrease in:
  • hip external rotation and abduction strength
• No evidence for a decrease in:
  • hip extension, flexion, adduction and internal rotation strength compared with the unaffected side.
• Conclusions:
  • Females with patellofemoral pain syndrome demonstrate a decrease in abduction, external rotation and extension strength of the affected side compared with healthy controls.

Nakagawa et al (2012)

• Cross-sectional design study
• Compared to controls, subjects with PFPS (when performing a single leg squat) demonstrated:
  • greater ipsilateral trunk lean, contralateral pelvic drop, knee abduction and hip internal rotation.
  • 18% less hip abduction strength
  • 17% less hip external rotation strength.
  • Less muscle activation of the gluteus medius.

Souza and Powers (2009)

• Cross sectional design
• Females with PFP (compared to the control group during running and a step down task) demonstrated:
  • Greater peak hip internal rotation.
  • Diminished hip torque production (14% less hip abductor strength and 17% less hip extensor strength).
  • Significantly greater gluteus maximus recruitment.

Bolgla et al (2008)

• Cross sectional design
• Conclusions/Results:
  • Subjects with PFPS had significant hip weakness but did not demonstrate altered hip and knee kinematics as previously theorized. Additional investigations are needed to better understand the association between hip weakness and PFPS etiology.

Treatment of Patellofemoral Pain

Davis and Powers (2010)

• Research review/summary.
• Foot orthoses:
  • Have been reported to produce positive clinical outcomes.
  • The mechanism of action is currently unclear.
• A number of conservative interventions have evidence from high quality randomized clinical trials or systematic reviews to support their short-term effect on PFPS. These include exercise therapy, patellar taping, foot orthoses, and multimodal physiotherapy approaches.
• There is limited evidence from high quality randomized clinical trials or systematic reviews to support the use of hip muscle retraining/strengthening, or manual therapies.
• There is no evidence supporting the use of EMG bio-feedback or electrical stimulation as adjuncts to treatment.
• There is limited evidence to support long-term efficacy (at least 12 months) of conservative treatments. However, longer-term benefits may require sustained treatment regimens (beyond the 6-8 treatments routinely employed).
• There is limited evidence that faulty gait patterns associated with PFPS can be improved, resulting in improvements in pain and function.

Frye et al (2012)

• Systematic Review
• Objective:
  • Examine the effects of exercise and rest on decreasing pain (visual analog scale) and increasing function (Kujala Scoring Questionnaire) using human participants.
• Conclusions/Results:
  • Exercise is the more effective treatment for immediate decrease in pain and increase in function although these differences appear to be less distinguishable over time.

Callaghan and Selfe (2012)

• Systematic Review
• Objective:
  • To assess the effects, primarily on pain and function, of patellar taping for treatingpatellofemoral pain syndrome in adults.
• Conclusions/Results:
  • The currently available evidence from trials reporting clinically relevant outcomes is low quality and insufficient to draw conclusions on the effects of taping, whether used on its own or as part of a treatment programme.

Bolgla and Boling (2011)

• Systematic Review
• Objective:
  • To provide an update on the evidence for the conservative treatment of PFPS.
• Conclusions/Results:
  • General quadriceps strengthening continues to reduce pain in patients with PFPS.
  • Data are inconclusive regarding the use of patellar taping, patellar bracing, knee bracing, and foot orthosis.
  • Emerging data suggests the importance of hip strengthening exercise, ongoing investigations are needed to better understand its effect on PFPS.

Harvie et al (2011)

• Systematic Review
• Objective:
  • Evaluate the parameters of exercise programs reported in primary research, to provide clinicians with evidence-based recommendations for exercise prescription for patellofemoral pain.
• Conclusions/Results:
  • Currently, the primary research on this topic supports the use of closed kinetic chain, strengthening exercises for musculature of the lower limb, combined with flexibility options.
  • The current evidence base supports a prescription of daily exercises of two-four sets of ten or more repetitions over a period of 6 weeks or more.

Fagan and Delahunt (2008)

• Systematic review
• Conclusions/Results:
  • No randomised controlled trials exist to support the use of hip joint strengthening in subjects with PFPS.
  • Physiotherapy treatment programmes appear to be an efficacious method of improving quadriceps muscle imbalances.
  • Further studies are required to determine the true efficacy of therapeutic patellar taping.
  • Both open and closed kinetic chain exercises are appropriate forms of treatment for subjects with PFPS.

References:

Barton CJ, Levinger P, Menz HB, Webster KE. Kinematic gait characteristics associated with patellofemoral pain syndrome: a systematic review. Gait Posture. 2009 Nov;30(4):405-16.

Bolgla LA, Malone TR, Umberger BR, Uhl TL. Hip strength and hip and knee kinematics during stair descent in females with and without patellofemoral pain syndrome. J Orthop Sports Phys Ther. 2008 Jan;38(1):12-8.

Bolgla LA, Boling MC. An update for the conservative management of patellofemoral pain syndrome: a systematicreview of the literature from 2000 to 2010. Int J Sports Phys Ther. 2011 Jun;6(2):112-25.

Callaghan MJ, Selfe J. Patellar taping for patellofemoral pain syndrome in adults. Cochrane Database Syst Rev. 2012 Apr 18;4:CD006717.

Cook C, Mabry L, Reiman MP, Hegedus EJ. Best tests/clinical findings for screening and diagnosis of patellofemoral pain syndrome: a systematic review. Physiotherapy. 2012 Jun;98(2):93-100.

Crossley K, Cook J, Cowan S, McConnell J. Anterior knee pain. In: Brukner P, Khan K, editors. Clinical sports medicine. Sydney (Australia): McGraw-Hill; 2012. p. 684-714.

Davis IS, Powers CM. Patellofemoral pain syndrome: proximal, distal, and local factors, an international retreat, April 30-May 2, 2009, Fells Point, Baltimore, MD. J Orthop Sports Phys Ther. 2010 Mar;40(3):A1-16.

Fredericson M, Yoon K. Physical examination and patellofemoral pain syndrome. Am J Phys Med Rehabil. 2006 Mar;85(3):234-43.

Frye JL, Ramey LN, Hart JM. The effects of exercise on decreasing pain and increasing function in patients with patellofemoral pain syndrome: a systematic review. Sports Health. 2012 May;4(3):205-10.

Harvie D, O’Leary T, Kumar S. A systematic review of randomized controlled trials on exercise parameters in the treatment of patellofemoral pain: what works? J Multidiscip Healthc. 2011;4:383-92.

Nakagawa TH, Moriya ET, Maciel CD, Serrão 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 Jun;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 Feb;14(1):54-9.

Lankhorst NE, Bierma-Zeinstra SM, van Middelkoop M. Risk factors for patellofemoral pain syndrome: a systematic review. J Orthop Sports Phys Ther. 2012 Feb;42(2):81-94.

Prins MR, van der Wurff P. Females with patellofemoral pain syndrome have weak hip muscles: a systematic review. Aust J Physiother. 2009;55(1):9-15.