Locked knee

Locked Knee refers to a condition where the knee joint becomes immobilized in a fixed position, making it difficult or impossible to bend or straighten the knee. This condition can result from various causes, including mechanical obstructions within the joint, such as a torn meniscus, loose bodies, or severe arthritis, as well as from conditions that affect the muscles and ligaments surrounding the knee, leading to a functional lock.

Causes

Locked knee can be categorized into two main types: mechanical and pseudo-locking.

• Mechanical locking occurs when there is a physical obstruction within the knee joint. Common causes include:
  • Meniscus Tear: A tear in the cartilage of the knee, which can cause a piece of the meniscus to block the joint.
  • Loose Bodies: Small pieces of bone or cartilage that become loose and move around within the joint.
  • Severe Osteoarthritis: Degeneration of the joint can lead to the formation of bone spurs and rough surfaces that interfere with movement.

• Pseudo-locking or functional locking occurs due to pain or muscle spasm without an actual mechanical block. Causes might include:
  • Ligament Injury: Injuries to the knee ligaments can cause pain and swelling, leading to a reflex inhibition or spasm of the muscles around the knee, which makes it difficult to move the joint.
  • Patellar Dislocation: Dislocation of the kneecap can lead to acute pain and a sensation of locking, although the joint itself is not mechanically blocked.

Symptoms

Symptoms of a locked knee include:

• Inability to fully straighten or bend the knee
• Pain in the knee, especially when attempting to move it
• Swelling of the knee joint
• A feeling of the knee being stuck in one position

Diagnosis

Diagnosis of a locked knee involves a thorough medical history and physical examination by a healthcare professional. Imaging tests such as X-rays, MRI, and CT scan may be used to identify the cause of the lock.

Treatment

Treatment for a locked knee depends on the underlying cause. Options may include:

• Conservative treatments: Rest, ice, compression, and elevation (RICE), Physical Therapy, and medications to reduce pain and inflammation.
• Surgical intervention: In cases where mechanical locking is caused by loose bodies or a meniscus tear, surgery may be necessary to remove the obstruction or repair the damaged structures.

Prevention

Preventive measures for a locked knee focus on maintaining knee health through regular exercise, weight management, and avoiding activities that put excessive stress on the knees.