Patellofemoral Pain / Chondromalacia

August 13th, 2022

Patellofemoral Articulation

  • patella (kneecap) acts as pulley system for quadriceps muscle action over knee; makes contact with and moves over groove in femur (thigh bone) at knee
  • smooth, hard cartilage covers and protects undersurface of patella
  • patellar cartilage is avascular (no blood supply, therefore no nourishment provided via circulatory system)
  • synovial fluid (produced within knee joint) bathes internal joint structures lubricating and nourishing joint surfaces (thus maintaining resilience of cartilage)
  • patellar rocking motion with alternate compression-release activity between patella and femoral groove (during movement of knee) produces sponge-like synovial fluid exchange throughout substance of patellar cartilage
  • optimally, opposing surfaces of patella and femoral groove glide smoothly with patella rocking from top to bottom as it tracks centrally in femoral groove
  • centralized tracking ensures that opposing cartilaginous surfaces exchange rejuvenating synovial fluid

Patellofemoral Pain/Chondromalacia

  • knee pain +/-swelling (esp with run/walk/jump/squat/cycling, prolonged sitting, or downhill/stairs walking)
  • results from overuse/load, muscle strength imbalance, malalignment, and/or structural anomalies (may be multifactorial)
  • deviation of patella (off-center tracking of patella in femoral groove) occurs due to inner thigh muscle weakness or wasting and/or biomechanical malalignment at lower leg
  • off-center tracking disturbs normal distribution of synovial fluid resulting in degeneration (softening and eroding) of protective cartilage exposing underlying bone to compressive forces
  • basketball, volleyball, and soccer are sports which most commonly provoke this condition

Physical Therapy Treatment

  • application of electrotherapeutic modalities and ice
  • recommended temporary relative rest from, or modification of, causative and provocative activities
  • substitution of non-impact activities (e.g., swimming, elliptical trainer) versus e.g., running
  • exercises (+/- taping or bracing) to centralize patellar tracking
  • conditioning and functional re-training activities are assigned if normal routine of daily living has been negatively impacted by this condition
  • assessment of foot-ankle biomechanics and footwear evaluation and recommendations for selection of appropriate walk/running shoes


  • recovery may take three to six weeks or more
  • number of treatments required will vary with degree of inflammation but, typically, adolescents will require up to eight treatments whereas adult patients may resolve more slowly
  • more than one episode of PFPS may occur in adolescence during growth period when cartilage is relatively soft and vulnerable to compressive forces

Physio Note: Prevention

A good warm-up prior to sport activity and regular stretching of quadriceps, hamstrings, hip abd/adductors and external rotators, iliotibial band, and calf muscles (hold each stretch for 20 seconds; repeat 2 times per stretch; stretch at least 2 times a day) are recommended. Maintain quadriceps and hip muscle strength

Examine your running shoes periodically for degree and pattern of wear and correct alignment.

Your physical therapist can help you recognize footwear faults and will assess lower extremity alignment and functional dynamics (e.g., gait). Orthotics (custom-fitted insoles) may be indicated where structural or malalignment faults are identified