What is Ligament Laxity?
If you have ever met anybody who was “double jointed”, they probably have a conditioned called Ligament Laxity or Joint Hypermobility. This refers when a person can move a body part or joint beyond its normal range of motion. Most of the time ligament laxity is asymptomatic. When it does cause pain, it is usually in big joints such as the knees and elbows although it can be present anywhere in the body. There are many causes including variations in anatomy: bones with different shapes and tendons with different strengths.
Who gets it most?
Some degree of joint hypermobility can be found in up to 15% of the healthy adolescent population. This number drops as people reach their skeletal maturity. Girls tend to be more mobile than boys due to their body structure. It is unclear why some kids who present with ligament laxity have pain while others do not.
What are the symptoms?
Some symptoms commonly seen include being able to continue extending your knees and/or elbows after straightening them out. Larger joints in the body may become swollen and tender after physical activity. Fallen arches/flat feet and knock knees can be a result of ligament laxity as well. Sometimes the children may get easily injured doing something that their friends can do without any issues.
How do we test/diagnose?
A simple physical exam by your physician can diagnose this condition. Other medical conditions can cause joint hypermobility. Blood tests, X-Rays, and skin biopsies can often rule out more pathologic diseases such as collagen disorders and Marfan’s disease.
How do we treat? surgical/nonsurgical?
Ligament laxity is usually a self limiting condition. As kids get older, their tendons and ligaments contract and strengthen. Until that happens, it is a good idea to support flat feet and knocked knees caused by hypermobility with custom orthotics. This will maintain the shape of the arch and decrease strain in knees in knocked kneed patients. In more severe cases, physical therapy is needed to help supplement the skeletal maturity process. When an injury occurs due to hypermobility, it is important to brace the injured limb to aid in recovery. Prolonged immobilization when not acutely injured can actually weaken the surrounding tissue and make them more loose.
How do we prevent?
Children already diagnosed with ligament laxity should avoid activity that exacerbates certain positions. For example, sitting “indian style” can further stretch out knee ligaments. Wearing custom supportive inserts in shoes can prevent further flattening of kids feet.