Agility Physiotherapy &
Exercise Physiology
Treatment of Anterior Knee Pain
What is anterior knee pain?
Osteoarthritis is a chronic disease that affects many joints in the adult body, most commonly the knees, hips and hands. There is currently no cure for osteoarthritis, but there are many treatments and approaches to managing the long-term symptoms of this disease. Initially, osteoarthritis was considered to be a disease of articular cartilage, but recent research has indicated that the condition involves the entire joint. The loss of articular cartilage is often the primary change, but a combination of cellular changes and biomechanical stresses causes several secondary changes, including subchondral bone remodeling, the formation of osteophytes, the development of bone marrow lesions, change in the synovium, joint capsule, ligaments and periarticular muscles, and meniscal tears and extrusions.
What are the symptoms of anterior knee pain?
Anterior knee pain means pain at the front of the knee that often feels behind, below or beside the kneecap. Pain can be worse when the knee is bent and there will be a myriad of weak and tight muscles, including quadriceps, gluts, hamstrings and calf muscles. Often the knee joint might be slightly flexed (flexion contracture) and there will be increased pain when descending stairs or walking down a hill.
Diagnostic criteria for anterior knee pain
Diagnosis of anterior knee pain has focused on the impairment associated with presentation and a recent study looked at three subgroups that then corresponds to specific targeted interventions. The battery of tests include:
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Hand held dynamometry for hip abductor strength
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Hand held dynamometry for quadriceps strength
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Medial-lateral patellar mobility test
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Foot Posture Index (FPI)
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Rectus femoris length test
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Hamstrings length test
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Gastrocnemius length test
Subgroup derived targeted intervention for patellofemoral pain, three subgroups were found:
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“weak and tight” (39% of participants)
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“weak and pronated” (39%)
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“strong” (22%).
What conditions present as anterior knee pain?
Children and adolescents - patellar subluxation, tibial apophysitis (Osgood-Schlatter lesion), jumper's knee (patellar tendinopathy), referred pain: slipped capital femoral epiphysis, osteochondritis dissecans (OCD).
Adults - patellofemoral pain syndrome (chondromalacia patella), medial plica syndrome, pes anserine bursitis, ligamentous sprains (anterior cruciate, medial collateral, lateral collateral), meniscal tear, inflammatory arthropathy such as rheumatoid arthritis, Reiter's syndrome and septic arthritis.
Older adults - osteoarthritis, gout, pseudogout, popliteal cyst (Baker's cyst).
What is the most appropriate outcome measure to evaluate the treatment of anterior knee pain?
The lower extremity functional scale (LEFS) is a valid patient-rated outcome measure for the measurement of lower extremity function.
Guideline-based treatment of anterior knee pain
The management of anterior knee pain at Agility Physio & Ex Phys is based on impairments associated with the condition causing anterior knee pain, interventions that are strongly recommended:
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Manual therapy to increase flexion contracture
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Hip abductor strengthening
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Quadriceps strengthening
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Patella stabilisation or mobilisation
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Foot orthotics
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Strength at length for quadriceps, hamstrings and calf muscles
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Stretching, foam rolling or tape is not recommended
The two largest subgroups were both classified as having weak quadriceps and hip abductor muscles; these subgroups might benefit from strengthening exercises. In addition to being weak, individuals in the “weak and pronated” subgroup had a significantly higher mean Foot Posture Index (FPI- 6 or more is clinically relevant for treatment needs) than the other two groups. Therefore, in addition to strengthening exercises prescribing a correcting foot orthotic to people meeting this criteria in the “weak and pronated group” might also be beneficial.
The third identified subgroup (“strong”) is a previously unrecognised group that falls outside the current treatment recommendations as no weakness in strength or shortening in muscle length was identified. The people in this subgroup also experienced higher levels of function and quality-of-life and the hypothesis is that this group is overloading their patellofemoral joint due to reduced motor control. Therefore perhaps proprioceptive and/or neuromuscular retraining is the answer for improving their anterior knee pain.
What guideline/consensus statements does Agility use in the treatment of anterior knee pain?
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Selfe J, et al. Anterior knee pain subgroups: the first step towards a personalized treatment. Annals of Joint 2018; 3: 32.
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Calmbach WL, Hutchens M. Evaluation of patients presenting with knee pain: Part II. Differential diagnosis. American Family Physician 2003; 68: 917-922.