2. Chapter 18
The Knee

3. Objectives Upon completion of this chapter, you should be able to:
Describe the functions of the knee
Describe the ligament structure of the knee
Explain the function of the patellofemoral joint
List and define various sports-related injuries of the knee

4. The Knee One of the most complex joints in the body
Most movements and activities depend on it for support and mobility
There is risk of overuse and traumatic injury in both contact and noncontact sports

5. The Knee (cont’d.) Two types of cartilage in the knee joint:
Articular cartilage
Menisci

6. The Knee (cont’d.) Ligaments Medial collateral ligament (MCL)
Lateral collateral ligament (LCL)
Anterior cruciate ligament (ACL)
Posterior cruciate ligament (PCL)

7. The Knee (cont’d.) Patellofemoral joint
Allows knee flexion and extension to occur with a lesser amount of quadriceps force

8. Knee Injuries Patellofemoral problems
Articulation of the patella with the femur
Symptoms: aching pain in the front or behind the knee, knee is giving way, crepitus, patellofemoral joint pain, and mild swelling
Treatment: correct suspected causes, shoe inserts, taping and bracing, and stretching

9. Knee Injuries (cont’d.)
Patellar tendonitis
Inflammation of the patellar tendon
Caused by high-force, repetitive strain
Symptoms: anterior knee pain and local tenderness
Treatment: activity modification, stretching, ice, bracing, and taping

10. Knee Injuries (cont’d.)
Fat pad syndrome
Infrapatellar fat pad is a region of fatty tissue that lies underneath the patellar tendon
Symptoms: pain just below the patella, tenderness, and swelling
Treatment: special strengthening exercises, taping, icing, and anti-inflammatory medications

11. Knee Injuries (cont’d.)
Medial collateral ligament (MCL) sprain
Caused by a blow to the outside of the knee or a high-energy twisting
Symptoms: limited motion, swelling of the medial knee, tenderness, and pain
Treatment: PRICE, protective wrap, a brace or crutches, rehabilitation

12. Knee Injuries (cont’d.)
Torn anterior cruciate ligament
Females are now more susceptible
Can occur from contact or noncontact causes
Symptoms: hearing a “pop” followed by effusion, knee buckling, nausea
Treatment: splinting, icing, and compressive wrapping, crutches, reconstructive surgery, rehabilitation

13. Animation - ACL
Click Here to Play ACL Animation

14. Knee Injuries (cont’d.)
Posterior cruciate ligament tear
Most occur during a fall on the flexed (bent) knee with the foot plantar flexed or hyperflexion (bending too far) of the knee
Symptoms: positive “sag test”
Treatment: PRICE, physical therapy and rehabilitation

15. Knee Injuries (cont’d.)
Meniscus tears
Occur when the knee is twisted suddenly and one or both menisci become trapped between the femur and tibia or ligaments in and around the knee are torn
Symptoms: slow and mild knee swelling, pain, popping, locking, or giving way of the knee
Treatment: compressive wrap, crutches, knee supports, activity modification, medications, and physical therapy

16. Knee Injuries (cont’d.)
Epiphyseal (growth-plate) injuries
Knee is subject to sports-induced trauma at the centers of bone growth in skeletally immature athletes
May alter the length of the affected bone
Serious injury for a growing athlete

17. Knee Injuries (cont’d.)
Osgood-Schlatter condition
Group of symptoms involving the tibial tubercle epiphysis
Symptoms: pain, swelling, weakness, and a visible lump
Treatment: preventing progression, protective gear, ice, improving flexibility, and stretching

18. Knee Injuries (cont’d.)
Iliotibial band syndrome
Occurs when there is inflammation of the iliotibial band
Irritation usually occurs over the outside of the knee joint, at the lateral epicondyle
Treatment: rule out mechanical problems or training errors, proper footwear, ice, and stretching

19. Knee Injuries (cont’d.)
Fractures
Result of high-energy trauma
Vary in location and severity
Patella fracture is usually the result of direct impact to the anterior knee
Distal femoral and proximal tibial fractures may occur from violent twisting injuries

20. Conclusion
The knee is the largest joint in the body, and one of the most prone to injury
Made up of the femur, tibia, and patella
Also contains large ligaments that help control motion
These ligaments connect bones and brace the joint against abnormal types of motion
Other parts of the knee, like cartilage, cushion the joint and help it absorb shock during motion