Patellofemoral Pain Syndrome (PFPS) Flashcards
1
Q
Potential causes of patellofemoral pain
A
- frequent & excessive loading (unaccustomed)
- biomechanical
- ischemic mechanism
- pain science: centralized pain response
- females > males
2
Q
Demographics and extrinsic factors for patellofemoral pain
A
- 12-17 years old, female, and higher BMI
- rapid changes in training intensity, altered training surfaces, incorrect/overused footwear, high frequency LE overload
3
Q
Intrinsic factors for patellofemoral pain
A
- strength
- path-mechanical
- neuromuscular control
- flexibility
- psychosocial factors: social support, poor self perceived health, mental distress, & catastrophizing
- centralized pain response
4
Q
Arthrokinematics of the patella
A
- provides biomechanical advantage to the quad extensor mechanism
- joint stress is dissipated by thick hyaline cartilage covering the patella’s undersurface
- full knee extension = no patella contact with femur
- patellofemoral joint reaction force = angle dependent, force of the quads & patella tendon at the patellofemoral joint contact area
5
Q
Causes of patella femoral joint malalignment
A
- Bony morphology: trochlear dysplasia can lead to excessive lateral tilt & lateral malalignment of the patellofemoral joint, decreasing contact area & increasing stress
- Tight lateral structures: excessive tightness of lateral reticular structures has been associated with increased lateral compression of the patellofemoral joint, ITB tightness due to distal fibers merging with superficial & deep fibers of the lateral retinaculum
- patella atlas can increase patellofemoral contact force & stress upon knee flexion
6
Q
Possible proximal mechanisms for PF tracking
A
- patellofemoral joint reaction force based on angle dependent force of the quads & patellar tendon
- motions originating at the hip during functional activities may result in laterally directed patellofemoral joint contact
- can be attributed to femoral IR under a stable patella
- recent perspective is increased femoral IR
7
Q
Possible distal mechanisms for PT tracking
A
- excessive ER of the tibia may also influence lateral facet compression of the patella
- rotational force is applied to the patella at the inferior pole via the patellar tendon
8
Q
Pathogenesis PFPS
A
- frequent & excessive loading of the patellofemoral joint & the surrounding tissue outside the joint’s “envelope of function” can induce loss of musculoskeletal tissue homeostasis, generating pain
- Possible inflammation in: patellar fat pad, synovium, patellofemoral ligaments, quadriceps tendon, patellar tendon, & subchondral bone
9
Q
Screening to rule out other causes of patellar pain
A
- teninopathy of patellar/quads
- apophysitis
- ITB syndrome
- pes anserine bursitis
- pre patellar bursitis/Hoffa disease
- ligamentous instability
- meniscus tear
- bipartite patella
- space occupying lesion
- osteoarthritis
- neuroma
- patellar condromalacia
- plica syndrome
- lumbar radiculopathy
- saphenous neuritis
10
Q
Outcome measures
A
- lower extremity functional scale (LEFS)
- knee outcome survey: ADL scale
11
Q
Impairment of body function
A
- pain in joint
- impaired ROM of single joints: patellofemoral mobility, knee/hip/ankle DF limitations
- impaired power production: quads, hamstrings, hip, ankle, pelvic/core
- soft tissue restrictions: iliopoas, rectus remoras, hamstrings, ankle PF muscles, ITB lateral patellar retinaculum
12
Q
Functional assessments
A
- single limb balance: excessive Trendelenburg, femoral ADD & IR, ips knee ABD, trunk sway, & foot pronation
- double leg squat: quad dominant, decreased DF with anterior COM
- single leg squat
13
Q
Interventions for therapeutic exercises
A
- focus on hip strength in open & closed chain focusing on hip ADD, extensors, ER, & core strength
- initial exercises should limit compressive patellofemoral joint forces (hip focus)
14
Q
Quad strengthening considerations for PFJ stress
A
- squatting at 90 degrees, 75 degrees, & 60 degrees of knee flexion = higher PFJ stress when compared to open chain
- open chain exercises at 30, 15, & 0 degrees of knee flexion = higher PFJ stress when compared to double leg squatting
- eccentric step downs must be pain free
- no need to isolate the VMO
15
Q
Compressive forces on the knee
A
- Closed chain squat: forces increase until 90 degrees then levels off or decreases
- Open chain weighted extremity: greatest JRF occurs at about 30-0 degrees of knee flexion
16
Q
Common quad exercise prescriptions seen in rehab
A
- Open kinetic chain exercises from 90 degrees knee flexion to about 60 degrees knee flexion
- closed chain exercises (mini squat) initially started 0-30 degrees then progressed as patient tolerates
17
Q
Interventions neuromuscular reeducation
A
- movement education
- task specific practice
- squatting mechanics
- running training
18
Q
Interventions stretching/manual therapy
A
- Manual therapy: patella mobs, tibiofemoral joint mobs, & talocrural joint mobs
- Soft tissue mobilization: quads, retinaculum, talocrural joint, iliopoas, TFL/ITB complex
19
Q
Interventions bracing/taping
A
- Bracing: may provide symptom reduction by increasing the patellofemoral contact area
- Taping: little to no change in patellar alignment, may alter proprioceptive input & increase tolerance to functional training
20
Q
Prevention: reduction of loading to the patellofemoral joint
A
- decrease running miles/volume
- avoid breast stroke kick in swimmers
- decrease volume of cutting/jumping sports
- avoid activities that involve excessive & deep squatting, or other prolonged knee flexion activities
21
Q
Surgical interventions
A
- Lateral release: arthroscopic release is currently reserved only for patients with an excessively tight lateral retinaculum & associated lateral tilt of the patella
- Proximal realignment: proximal reconstruction of the medial patellofemoral ligament
- Distal realignment: medial tibial tubercle transfer or an anteromedial tibial tubercle transfer
