(3) Pathologies of the patellofemoral complex Flashcards
What is the function of the patella?
- increases the mvmt of the quadriceps muscle
- bony protection
- reduces compressive forces on the quads tendon with resisted knee extension
- allows the transfer of forces evenly on underlying bone
What is Patellar Tendinopathy?
- Repetitive stress/loading of extensor mechanism (“Jumpers Knee”)
- Degenerative > Inflammatory
- Loss of arrangements of collagen bundles
- Clefts between bundles filled with mucoid ground substance
- Increased fibroblasts
- Neovascularization
What are the risk factors for developing PT?
- Genetics & bone structure
- Age
- Sudden increase in activity/intensity
- Training volume
- Increased BMI
- Decreased quads/hams flexibility
- Decreased quad strength
How does overuse tendinopathy develop (Pathogenesis)?
- Shear stress applied to tendon (rupture if excessive)
- Micro tears leading to inflammatory process
- Acute Inflammation = Tendinitis
- Neovascularization & nerve growth
- Collagen reorganization
What are the signs of tendinosis?
- Swelling
- Localized pain on palpation
- Pain on tendon loading
- Stiffness
- Crepitus
- Decreased strength
What are the clinical signs of PT on examination?
c/o Pain:
- sudden/gradual onset - localized
- intermittent
- activity related
o/e Pain on:
- resisted extension
- single leg squat
- palpation inf. pole/proximal tendon (in full extension)
- +ve Royal London Hospital test
What is the Royal London Hospital Test?
- with knee fully extended, local tenderness with palpation of tendon
- tender portion re-palpated with knee flexed 90 degrees
- +ve pain reduced or absent with knee flexion
What is the treatment for PT?
- Activity modification (load management)
- Maintain CV and pulmonary fitness
- Ice/heat/massage
- Corticosteroid/surgery (advise against)
- Isometric contractions in mid range as tolerated
- Voluntary contractions 70% max held 45 to 60 seconds (4 times twice/day)
What are the exercise rehab options for PT?
- Eccentric training programme
- Heavy slow resistance (HSR) training
- 4-stage rehab programme
What is the eccentric training programme for PT?
- 25 degree decline squat
- Single leg eccentric squats
- Concentric phase of squat
- 3 sets of 15 reps twice/day
- 7 days/week for ~12weeks
However…. - may be pain provocative if high irritability
- ignores other kinetic chain issues
- limited evidence
What is HSR training for PT?
Consists of:
- concentric/eccentric
- leg press
- squats and hack squats
- uses both lower extremities
- Progress 15RM to 6RM for 3/4 sets
- 3 times/week for 12/52
- involves high loads (70-85% of 1RM)
*1RM testing difficult due to pain
What is the 4 stage rehab programme for PT?
Stage 1 Isometric loading:
- initiate if more than min pain during isotonic exercises
- 5 reps 45 secs 2 to 3times/day
Stage 2 Isotonic loading:
- initiate if minimal pain during isotonic exercise
- 3 to 4 sets 15RM (progress to 6RM)
- Every second day
- fatiguing load
Stage 3 Energy-storage loading
- initiate if adequate strength and load tolerance
- progressively develop volume and then intensity to replicate sport
Stage 4 RTP
- initiate if load tolerance to energy storage exercises progression replicates sport
- progressively add training drills
What is Patellofemoral Pain Syndrome (PFPS)?
- pain from patellofemoral junction
- previously “Anterior knee pain”
- female > male
- recurrent/longstanding
- decreased QOL and functioning
What are the risk factors of PFPS?
- femoral anteversion
- external tibial torsion
- muscle imbalances (short/tight vs long/weak)
- Abd/quads weakness
- tight hamstring
- tight iliopsoas and quads
- tight iliotibial band
- tight gastrosoleus complex
- volume of activity
- environment
How do you test for hamstring tightness?
Passive knee extension test
- +ve knee extension >20
How would you test for iliopsoas and quadriceps tightness?
Modified Thomas test
- +ve iliopsoas inability of opposite thigh drop to neutral/below
- +ve quads knee flexion >80
How would you test for tightness of the iliotibial band?
Ober test
- +ve if leg remains abducted position
What are the clinical signs of PFPS on examination?
c/o
- pain anteriorly
- Agg. compressive forces (stairs, prolonged sitting, squatting)
- Crepitus
- giving way
o/e
- little to find
- +ve Clarkes’s test
- pain single leg squat
- pain on resisted quads
What is the treatment for PFPS?
- stretching/strengthening programs
- taping and bracing strategies
- activity modification
- orthotics
- education/rehab
- avoid “wait and see” approach
What is chondromalacia patella?
- Different to PFPS
- Softening of articular cartilage on articular groove surface of patella
- +/- trochlear groove
- fissuring and erosion
- Diminished load capability
What are the clinical signs of chondromalacia patella on examination?
c/o
- pain (anterior)
- crepitus
- swelling
o/e
- Same as PFPS
- pain on single leg squat
- +/- pain on resisted quads
What are the patella’s different planes of motion?
- flexion-extension
- medial-lateral patellar tilt
- medial-lateral rotation
- medial-lateral patellar shift
What is patellofemoral stability dependent on?
Osseous anatomy
- trochlea femur, patella position etc
Transverse stabilizers
- VM/VL muscles, ITB, MPFL, retinaculum
Longitudinal stabilizers
- extensor mechanism
What are the causes for Patellofemoral Instability?
- lateral instability
- subluxation
- dislocation
- traumatic (+/- recurrent)
- MoI: non contact twisting with knee extended and external rotation of foot
- non-traumatic: ligamentous laxity +/- PFPS presentation
