The most common reason for a child's knee locking is due to a tear in the cartilage that cushions the knee joint.
Understanding Knee Locking
A locked knee means that it's difficult or impossible to fully straighten or bend the knee. This can be painful and limit your child's ability to move. According to the reference provided, this issue often occurs when damaged cartilage gets caught within the knee joint, acting like a mechanical block.
Common Causes of Knee Locking
- Cartilage Tears: This is the primary reason for a locked knee, as noted in the reference. These tears can occur from an injury or over time.
- Meniscal Tears: The menisci are C-shaped pieces of cartilage that cushion and stabilize the knee joint. A tear in this cartilage can lead to fragments getting stuck in the joint, causing locking.
- Loose Bodies: Sometimes, small pieces of bone or cartilage can break off and float around within the joint, potentially getting caught and causing the knee to lock.
- Ligament Injuries: While less common for locking, injuries to ligaments can indirectly cause issues with knee movement.
- Osteochondritis Dissecans (OCD): This condition affects bone and cartilage, and can sometimes lead to locking symptoms if a piece of cartilage becomes loose.
What to Do if Your Child's Knee Locks
If your child's knee is locking, it's essential to:
- Avoid further stress: Stop any activities that could worsen the situation.
- Consult a doctor: A proper diagnosis is crucial to identifying the cause and determining the best treatment plan.
- Follow medical advice: Depending on the cause, treatment might involve rest, physical therapy, or surgery.
Diagnosis
Doctors might use:
- Physical exams: Checking the range of motion and identifying areas of pain.
- Imaging: X-rays, MRIs, or other scans can help visualize the problem.
- Arthroscopy: In some cases, a minimally invasive procedure to directly look inside the joint is needed for diagnosis and treatment.
Key Takeaway
| Cause | Description |
|---|---|
| Cartilage Tear | The most common cause; damaged cartilage gets caught in the joint, restricting movement. |
| Meniscal Tear | A tear in the meniscus can cause fragments to get stuck, leading to knee locking. |
| Loose Bodies | Fragments of bone or cartilage can cause locking when they get caught in the knee joint. |
| Ligament Injuries | Can contribute to instability, though less likely to directly cause locking compared to cartilage issues. |
| OCD | A condition affecting bone and cartilage that can lead to loose cartilage fragments, causing locking in some cases. |
Remember, a torn cartilage within the knee joint is a primary cause of a locked knee in a child. Consulting a healthcare professional for proper diagnosis and treatment is very important.
