Knee Injuries

By Cindy Greene

Introduction

• Very complex joint

• Most sports place extreme stress on the knees

• Very commonly injured joint

Skeletal Anatomy

• 4 bones make up the knee joint:

• • Femur

• • Tibia

• • Fibula

• • Patella

Meniscus

Functions: increases stability

of the joint, cushions stresses

•

Stabilizing Ligaments

• Anterior Cruciate Ligament

(ACL)

• Posterior Cruciate Ligament

(PCL)

• Medial Collateral Ligament (MCL)

• Lateral Collateral Ligament (LCL)

• Iliotibial band (IT)

ACL

ACL:

• Prevents anterior translation of the

tibia.

• Keeps the tibia from gliding forward.

• Very strong ligament

• Very susceptible to injury.

• Women more prone to tear ACL than

PCL

PCL:

• Prevents posterior translation

of the tibia.

• Only 90% of size of ACL.

• It is the strongest of the knee

MCL

MCL:

• Flat, broad ligament located on

the inside of the knee

• Prevents a valgus stress on the

knee.

• Part of it attaches to the medial meniscus

LCL

LCL:

• Cordlike ligament located on

the outside of the knee.

• Prevents a varus stress on the knee

Muscles of the Upper Leg

Knee injuries

• Knee is most injured joint in the body.

• 25% of all injuries involve the knee

• Nearly one million knee surgeries are performed each year.

• A knee injury is also the most likely injury to end an athletes career.

ACL Injuries

• Grade I- pain with minimal damage to the ligament.

• Grade II-more ligament damage and mild looseness of the joint.

• Grade III- The ligament is completely torn and the joint is very loose or unstable.

How Does it Occur?

• Forced twisting motions of the knee

• Hyperextension of the knee

• Sudden stops that cause the femur to push across the shin bone

Diagnosis

• History

• Physical exam

• Xray

• MRI

Treatment (Minor Injuries)

• RICE

• R-Use crutches and knee immobolizer

• I- Ice knee for 20-30 minutes every 3-4 hours for 2-3 days or until pain goes away.

• C-Wrap an elastic bandage around your knee to keep the swelling from getting worse.

• E-Keep knee elevated whenever possible.

Treatment (Major)

• Intensive Rehabilitation

• Surgery

Prevention

• Strengthen thigh and hamstring muscles• Increase flexibility.• Practice exercise (Patient Advisor pg 170)1. Heel Slide2. Quadriceps Isometrics3. Prone Knee Bends4. Passive knee extension5. Heel raises6. Wall squats

LCL Injury

• Causes: twisting motion or a blow to the fibula.

• Symptoms: pain on the outer side of the knee, swollen and tender knee, and sound or feel of a pop at the time of injury.

• Diagnosis: history, physical, Xray, MRI

• Treatment: RICE it!

MCL Injury

• Causes: blow to the outer side of the knee or twisting of the knee

• Symptoms: pain on the inner side of the knee, swollen and tender knee, having the feeling that your knee is “giving way”

• Diagnosis: history, physical, Xray, MRI

• Treatment: RICE it!

Patellar Tendonitis (Jumper’s Knee)

• Inflammation of the patellar tendon that connects the patella to the tibia

Patellar Tendonitis

• Causes: too much jumping, running, walking, improper alignment of the hip, legs, knees, or hips

• Symptoms: pain, tenderness and swelling

• Diagnosis: history, physical, Xrays, MRI

• The doctor will check for tenderness at the patellar tendon and pain with running, jumping, or squatting

Patellar Tendonitis

• Treatment: RICE it!

• Wear infrapatellar strap or brace and special orthotics for over-pronation.

• Prevention: Wear proper shoes and stretch!

Patellar Tendonitis Rehab Exercises

• Practice exercises (Patient Advisor pg 201)

1. Patellar mobility

2. Standing hamstring stretch

3. Quadricep stretch

4. Straight leg raise

5. Knee stabilization

Patellofemoral Pain Syndrome (Runner’s Knee)

• Pain behind the patella (includes patellofemoral disorder, patellar malalignment, runner’s knee, and chondromalacia)

•

Patellofemoral Pain Syndrome

• Causes: repetitive bending and straightening of the knee

• Symptoms: pain behind the knee cap, pain when you walk or run or sit for a long time, swelling, or snapping, popping or grinding in the knee

• Diagnosis: history, physical, Xray• Treatment: RICE it! Wear orthotics and/or

infrapatellar strap • Prevention: Strengthen thigh muscles

Other Knee Injuries

• Dislocation of the patella

• Illiotibial Band Syndrome

• Bursitis

Sports Specific

• Basketball: Result from the player taking a blow to the knee from the side. Also can be caused by changing direction of running abruptly

• Football: Can suffer from runner’s knee, jumper’s knee, dislocated knee

• Terrible Triad of O’Donahue: tears to the MCL, ACL, and the medial cartilage (“blew out a knee”)

Sports Specific

• Gymnastic/Cheerleading: Knee injuries can occur secondary to the knee hyperextending when tumbling or dismounting

• Runners: Runners can suffer from runner’s knee and illiotibial band syndrome. Foot strike and mechanics plays an important role in the prevention of knee injuries.