Knee Capsule Strain
The knee is the most frequently injured joint by teenage athletes. It is estimated over 2.5 million sports- related injuries occur every year. The knee is made of several structures that stabilize the joint.
The main structures are the femur, tibia, and patella (kneecap). These bones are encircled by a range of ligaments and tendons that stabilize the joint. In addition, a structure called the articular capsule surrounds the joint in layers to stabilize and support the knee.
The knee capsule has two main layers, an outer layer and an inner layer. The outer layer is a tough, fibrous membrane that is formed from ligament tissue. The inner layer is a synovial membrane and secretes synovial fluid. The knee capsule also contains bursae. These are fluid-filled sacs and are located behind the patella.
The key function of the outer layer of the knee capsule is to offer stability to the joint by keeping the bones of the knee in their proper positions. The synovial membrane located in the inner layer secretes synovial fluid. The synovial fluid lubricates the joint, thereby helping to reduce resistance and inflammation of the tendons, bones, and ligaments when the knee joint moves. In particular, the knee capsule permits the full knee to have bending motion due to the folds within the capsule.
Causes of Knee Capsule Strain Injury
A variety of mechanisms can cause injury to the knee capsule. But most frequently, the causes are:
- Hyperextension of the knee (generally injures the posterior capsule)
- External rotation
These two movements can also increase the risk of injury if enacted simultaneously. Other actions may that produce an injury include:
- Planting the foot and twisting the knee
- A direct blow to the knee
Symptoms of a Knee Joint Capsule Strain
Symptoms of a knee capsule strain injury may include:
- Decreased range of motion
- Sharp pain
- Tenderness in the joint
Frequently, pain from an injury to the knee capsule will worsen with activity and be relieved with rest. Additionally, activities such as bending the knee, weight-bearing, or walking can make the pain worse. Pain can span from mild to severe depending on how severe the injury is.
Treatment of Knee Capsule Strain
Knee capsule strain injury at-home treatments may include the RICE method:
Or the use of NSAIDs: Nonsteroidal anti-inflammatory drugs (such as ibuprofen).
Any knee injuries should be assessed by a medical expert promptly, particularly if no improvement has occurred with at-home treatments. An orthopedic physician may recommend physical therapy, which may involve:
- Range of motion exercises
- Stretching and strengthening and exercises 24-48 hours after minor injuries
- At home exercise plan
- Management of pain
The patient can return to normal activities gradually after the injury has healed. In some severe cases, knee surgery may be required to repair the damage.
Prevention of Knee Strain
Use the following guidelines to help prevent future knee capsule strain injury:
- Proper warm-up incorporating stretching before and after activities
- Wear shoes that fit correctly and offer good traction
- Avoid sudden changes in intensity when performing activities
- Utilize knee guards when contact with others may be involved
- Use appropriate techniques, especially with weight-bearing activities
- Keep a healthy weight to reduce excess stress on the knee
- Maintain strong, healthy leg muscles
It is important to practice regular injury prevention techniques to help keep your joints strong and healthy.
Need to schedule an appointment with one of Orthopaedic Associates of St. Augustine’s Sports Medicine Physicians, call 904-825-0540 or request an appointment online.