1. Chapter 14 Knee Injuries

2. The Knee Largest joint in the body Modified hinge joint
One of most vulnerable joints to severe injury of any in the body

3. Knee Anatomy Bones Tibia Fibula Femur Patella Distal to the femur
Major weight bearing bone
Fibula
Not included as a true knee bone
Very little weight bearing
Femur
Longest bone in the body
Major weight bearing
Patella
“floating bone”

4. Knee Anatomy Ligaments Anterior cruciate ligament (ACL)
“cruciate” means cross
Function of ACL and PCL is to stabilize the knee from front-to-back
Posterior cruciate ligament (PCL)
Medial collateral ligament (MCL)
Lateral collateral ligament (LCL)

5. ligaments Posterior cruciate ligament (PCL)
Medial collateral ligament (MCL)
Lateral collateral ligament (LCL)

7. Knee Anatomy Cartilage (meniscus)
menisci are horseshoe-shaped shock absorbers that help to both center the knee joint during activity and to minimize the amount of stress on the articular cartilage.

8. Meniscus Medial Lateral More often injured than lateral
Often involved medial ligament
C-shaped
Lateral
O-shaped

9. Knee anatomy Patellar tendon
Runs from the quadricep muscles, across the patella, and inserts into the tibial tuberosity

10. Knee Anatomy Muscles and tendons
Quadriceps-responsible for knee extension
Vastus lateralis
Vastus medialis
Vastus intermedius
Rectus femoris

11. Quadriceps

12. Posterior Leg Hamstrings-responsible for knee flexion Biceps femoris
Semimenbranosis
semitendinosis

13. Hamstrings

14. Injury prevention
Structural alignment can predispose an athlete to injury

15. Injury Prevention
Proper strengthening and flexibility of quadriceps, hamstrings, and gastrocnemius muscles

16. Injury Prevention
Preventative bracing for collateral ligaments

17. Genu valgum (knock-kneed)

18. Genu Varum (bow-legged)

19. Bracing

20. Knee injuries and Conditions
Ligament Injuries
Sprains (ACL, PCL, MCL, LCL)
1st, 2nd, and 3rd degree
Muscle and tendon injuries
Patellar tendinitis
Bone injuries
Chondromalacia
Patellar dislocations
Other common injuries
Meniscal injuries
Osgood-Schlatter disorder

21. Ligament Injuries

22. ACL injuries Function is to prevent tibia from moving forward on femur
S/S of injury include the athlete feeling disabled, complain of the knee giving way, collapsing, and popping

23. ACL Injuries Usually the most serious of all knee injuries
Can hear a pop or snap on injury
Often injured when athlete is changing direction

24. ACL (cont.) Can also be injured due to hyperextension
rapid swelling and loss of function
treatment- RICE, knee immobilizer, crutches, follow-up with orthopedist
Almost always require surgical reconstruction if torn

25. Surgical procedures Tendon graft Allograft Patellar or hamstring
Cadaver tendon

26. Rehabilitation 3 Phases of rehab include: Usually minimum 6 months
controlling the pain and swelling in the knee
regaining knee motion
beginning to regain muscle strength
Usually minimum 6 months
Conservative treatment for less active people can be non-surgical and focus on all rehab
three components of non-surgical treatment are physical therapy, activity modification, and the use of a brace

27. PCL injuries PCL prevents posterior tibial movement on the femur
MOI: bent knee bears full weight, forced hyperflexion, or a blow to the front of the tibia

28. PCL Often minimal swelling Treatment- RICE, refer to physician
Not often surgically repaired
Rehab focuses on strengthening quad muscles

29. MCL injuries
Usually results from a direct blow to the outside of the knee
Mild sprains result in joint-line point tenderness, minimal swelling, and no joint laxity

30. MCL
Moderate produces more swelling, discomfort, some loss of function, and some laxity
Severe – produces large amount of laxity

31. MCL (cont.) Treat with RICE if mild
Moderate, may need immobilizer, rehab
Moderate to severe could involve the meniscus and/or ACL and may require surgery

32. LCL injuries Less common than MCL injuries
Usually occurs due to direct blow to medial side of knee

33. LCL Similar s/s except discomfort is on lateral aspect of knee
Focus rehab on lateral thigh muscles and hamstrings

35. Muscle and tendon injuries
Patellar tendinitis
Characterized by quad weakness and tenderness over patella
Minimal swelling
Called jumper’s knee

36. Patellar Tendinitis Pain after activity
Treat with ice, NSAIDs, and restricting activity
Rehab- address flexibility and weakness issues

37. Bone injuries Patellar-femoral syndrome
Pain and discomfort around the patella often caused by patellar tracking problems
Causes chondromalacia-the wearing away of the cartilage on the back of the patella

38. Patellar-femoral syndrome
s/s aching and pain after prolonged sitting, pain when going up or down stairs, athlete feels grinding sensation with flexion/extension

39. Patellar-femoral syndrome
Treatment involves correcting patellar tracking, strengthening vastus lateralis and medialis, improving flexibility of quads and hamstrings

40. Bone injuries Patellar dislocation Most commonly dislocates laterally
Occurs with bent knee and inward twisting
Noticeable deformity, extreme pain
Call EMS
Physician reduces

41. Patellar dislocation
Treatment involves immobilization, then rehab to regain mobility and strengthen
Can wear a knee sleeve post-injury to help prevent from happening again

42. Fractures Tib-fib fracture Uncommon, but immediate referral necessary
Many structures involved

43. Dislocated knee
Extremely rare
Immediate transport

44. Meniscal injuries
Typically occur with a twisting motion or with hyperextension or hyperflexion

45. s/s-pain over joint line, problems weightbearing, complain of clicking, catching, locking, inability to fully extend or flex, and swelling

46. Meniscal injuries
Treatment- surgical removal of meniscus (meniscectomy)
More often treated with removal of torn areas only through arthroscopy
Sometimes repair meniscus with sutures or staples
Numerous new methods of repair (i.e. transplants)
Aquatic therapy very useful (non-weight bearing)

47. Osgood-Schlatter disorder
Inflammation and irritation of the insertion of the patellar tendon (tibial tuberosity) in youth
Repeated stress and activity can cause patella to partially pull away from bone and cause a bump

48. Osgood-schlatter’s S/S- pain and discomfort, minimal swelling
Restricted activity recommended
Use pain as a guide for activity level
Ice pre and post activity, NSAIDs

49. Osgood-schlatter’s Can try patellar tendon band or pad
Usually improves by age 16 or 17

50. Osgood-Schlatter disorder

51. Special tests

52. Lachman’s test

53. Pivot shift test

54. McMurray’s test