1. The Knee

2. Basic Anatomy

3. Basic Anatomy Ligaments Attaches to the lateral femur & head of fibula
Anterior Cruciate Ligament (ACL)
Prevents femur moving posteriorly during weight bearing
Attaches anterior tibia to lateral femur
Posterior Cruciate Ligament (PCL)
Primary stabilizer & stronger than ACL
Attaches posterior femur to anterior tibia
Medial Collateral Ligament (MCL)
Taut during knee flexion & relaxed in extension
Prevents knee from valgus and external rotating forces
Attaches medial femur & medial tibia
Lateral Collateral Ligament (LCL)
Taut during knee extension & relaxed in flexion
Attaches to the lateral femur & head of fibula

4. Each meniscus is divided into 3 circumferential zones:
Medial meniscus: C-shaped fibrocartilage
Lateral meniscus: O-shaped fibrocartilage
Each meniscus is divided into 3 circumferential zones:
Outer zone = good vascular supply
Middle zone = minimal vascular supply
Innner zone = avascular

5. Knee Injuries

6. Prevention of Knee Injuries
Physical conditioning
Muscles surrounding knee joint must be strong and flexible
Focus on hamstring, erector spinae, groin, quadriceps, gastrocnemius flexibility
Rehabilitation and skill development
Strength, balance and technique - sport specific
Shoe Type
More and shorter cleats

7. valgus force (lateral blow) or severe outward twist
MCL sprain
Cause:
valgus force (lateral blow) or severe outward twist
Greater injury results from medial sprains vs. lateral sprains

8. S&S:
Grade I = few ligamentous fibers are torn and stretched; joint is stable, little/no swelling, possible joint stiffness & point tenderness, full ROM
Grade II = complete tear of deep cpsular ligament and partial tear of of MCL; slight laxity in full extension, no gross instability; no/little swelling; moderate to severe joint stiffness with inability to fully extend the knee; decrease PROM; medial pain
Grade III = complete loss of medial instability; swelling; immediate severe pain followed by dull ache; loss of motion because effusion and hamstring guarding
Care: RICE; crutches; immobilzer; ROM exercises; rehabilitation; hinge brace (grade I, II)

9. LCL sprain
Cause:
varus force & internal rotation of the tibia
Less prevalent than MCL

10. S&S:
Grade I = joint is stable, little/no swelling, possible joint stiffness & point tenderness, full ROM
Grade II = slight laxity in full extension, no gross instability; no/little swelling; moderate to severe joint stiffness with inability to fully extend the knee; decrease PROM; lateral pain
Grade III = complete loss of lateral instability; swelling; immediate severe pain followed by dull ache
Care: RICE; crutches; immobilzer; ROM exercises;rehab; hinge brace; surgery controversial

11. ACL sprain Cause: foot planted, femur externally rotated
S&S: hear/felt “pop”; immediate disability; rapid swelling; intense pain immediately then subsiding
Care: RICE; crutches; immobilizer; surgery likely; 3-5 wks in brace; rehab 4-6 months

12. PCL sprain Called the most important ligament in the knee
Provides central axis for rotation
Provides ~95% restraint of posterior displacement of tibia
Cause: most at risk when knee is bent hyperflexed knee with full weight on anterior aspect of knee and foot plantarflexed; rotational force which may affect medial/lateral side of knee
S&S: pop in back of knee; tenderness and swelling in back of knee (popliteal fossa); laxity of ligament
Care: RICE; Grade 1 & 2 - non-op, rehab focusing on quad strengthening; rehabilitation; controversy over surgery

13. Meniscus injuries
Cause: weight bearing combined with rotational stress while extending/flexing knee
S&S: may or may not result in effusion gradually over hrs; joint line pain and loss of motion; intermittent locking/giving way; pain with squatting
Care: RICE; recovery depends on location of tear; not uncommon to return 6-14 days after surgery (menisectomy); repaired meniscus may require immobilization for 5-6 wks, longer recovery

14. Bursitis
Cause: acute, chronic, recurrent; prepatellar and deep infrapatellar have highest incidence; prepatellar inflamed from continued kneeling or falling directly on knee; infrapatellar irritated from overuse of patellar tendon
S&S: localized swelling; redness; increased temperature; pain due to swelling
Care: eliminating cause; rest; swelling; compression; padding; NSAIDs; possible aspiration

15. Iliotibial band friction syndrome (Runners knee)
Overuse condition commonly in runners and cyclists who have genu varum and pronated feet
Irritation develops at the band’s insertion over the lateral femoral condyle causing friciton

16. Cause: overuse that can be attributed to malalignment and structural asymmetries of the foot and lower leg;
S&S: tenderness along ITB; little/no swelling; pain increases with activity
Care: stretch ITB; massage; foam roller: correction of foot and leg alignment problems; ice

17. Chrondromalacia
softening and deterioration of the articular cartilage on back of patella
Exact cause is unknown
Abnormal patellar tracking due to numerous factors
Chondromalacia undergoes 3 stages:
Stage 1 = swelling and softening of articular cartilage
Stage 2 = fissuring of the softened articular cartilage
Stage 3 = deformation of the surface of the articular cartilage caused by fragmentation

18. Chondromalacia
S&S: pain anterior knee while walking, running up/down stairs or squatting; recurrent swelling around kneecap; grating sensation when flex/ext knee
Care: avoid irritating activities; isometric ex; NSAIDs; neoprene sleeve; possible sx

19. Patellar tendonitis (jumper’s knee)
Cause: jumping, running, or kicking repetitively
Sudden or repetitive forceful extension of knee may begin an inflammatory process that will eventually lead to tendon degeneration
S&S: tenderness; pain;
3 stages:
Stage 1 - pain after activity
Stage 2 - pain during and after but functional
Stage 3 - pain during and prolonged after activity; may progress to constant
Care: avoid irritating activities; RICE; patellar tendon brace; NSAIDs; transverse friction massage (TFM)

20. Osgood-Schlatter disease
Cause: adolescent; repeated pull of patellar tendon at the tibial tubercle; bony callus forms and tubercle enlarges; usually resolves in late teen years
S&S: repeated irritation causing swelling; hemorrhage, and gradual degeneration of tibial tubercle; severe pain when kneeling; jumping and running; point tenderness
Care:  stressful activities; ice before and after activity; isometric strengthening of quads and hams

21. Patellar dislocation
Cause: quad muscle pulls in a straight line and patella pulls laterally creating a force that may sublux/dislocate patella
S&S: complete loss of knee function; pain with swelling; obvious deformity; possible fracture
Care: ice; referral with a dislocation -
spontaneous reduction may occur if
athlete is able to straighten knee

22. Osteochondritits Dissecans
A painful condition involving partial or complete separation of a piece of articular cartilage and subchondral bone
Exact cause is unknown
Possible causes =
direct or indirect trauma
skeletal or endocrine abnormalitites
prominent tibial spine or part of patella impinging on medial femoral condyle

23. S&S: achy knee, swells recurrently, may catch or lock, possible atrophy of quadriceps
Care: for children, rest and immobilization; may take as long as 1yr to resolve; surgery = drilling in the area to stimulate healing, pinning loose fragments, or bone grafting
(Amare Stoudamire, Greg Oden)