Being ‘Double-Jointed’ Can Be a Pain for Some Kids

When a child or adolescent experiencing chronic joint pain or dislocations visits Roger Saldana, M.D., a pediatric orthopedic surgeon with Miami Orthopedics & Sports Medicine Institute at Baptist Children’s Hospital, one of the conditions he looks for carries a very clinical-sounding name: benign joint hypermobility syndrome or hypermobile ligamentous laxity.

But this condition is much more commonly referred to as “double-jointed.”

The clinical signs are joints that are more flexible than usual and can be extended, sometimes easily and painlessly, beyond the normal range of motion. The condition occurs when the tissues holding the joint together, mainly ligaments, are too loose, Dr. Saldana says.

Signs of the Syndrome  

Benign joint hypermobility syndrome is thought to be an inherited connective tissue disorder. Up to 15 percent of children have the condition, which can affect a few joints or every joint in their body. The first step to diagnosing joint hypermobility syndrome is calculating the Beighton score, which measures generalized joint laxity by testing and observing five maneuvers:

• The wrist and thumb can be moved downward so the thumb touches the forearm.
• The little fingers can be extended back beyond 90 degrees.
• The knees are abnormally bowed backward when standing and viewed from the side.
• The arms bend further than normal, beyond straight, when fully extended.
• The palms can be placed flat on the floor when bending at the waist and keeping the knees straight.

When a child presents with joint pain and swelling, conditions such as juvenile arthritis or other inflammatory conditions should be ruled out. It’s also important to note that benign joint hypermobility syndrome is different from other disorders that cause generalized joint laxity, such as Marfan syndrome and Ehlers–Danlos syndrome.

Many children and adolescents with benign joint hypermobility syndrome have no debilitating symptoms and often succeed in activities that require flexibility, such as gymnastics and ballet. On the other hand, some children and teens with the condition, especially those who are active or involved in sports, experience joint pain, swelling, dislocations and sprains.

“The joints most commonly affected are the shoulders, knees and ankles,” Dr. Saldana said. “Excessive joint laxity leads to wear and tear on these joint surfaces and strains the soft tissue surrounding the joints.”

Physical Therapy Can Strengthen the Joint

To treat joint hypermobility syndrome, Dr. Saldana recommends physical therapy that focuses on strengthening the dynamic stabilizers of the affected joints as well as the surrounding muscles. The key is to get fit and stay strong. The more flexible a joint, the more muscle strength it takes to keep it within a normal range – and, if the muscle isn’t strong enough, the joint hyperextends and causes injury.

The good news: the majority of patients have positive results with physical therapy. However, Dr. Saldana says that a small percentage of patients do not respond to therapy and need surgery to stabilize the joint and avoid repeated dislocations. Knee surgery to prevent recurrent kneecap dislocations is the most common surgery Dr. Saldana performs. “Dislocations create wear and tear on the joint, which puts a patient at increased risk for osteoarthritis later in life,” he explained.

Some adolescents with joint hypermobility syndrome can voluntarily pop their joints out of place – a practice Dr. Saldana highly discourages. “I advise my patients to avoid demonstrating their hypermobility to impress friends and family,” he said. “Like a dislocation, the repeated motion can be detrimental to long-term joint health.”

It’s also important to determine if a child’s involvement in sports is causing pain or dislocations. “If a child has shoulder instability, for example, sports with overhead motion such as volleyball and swimming may not be good options,” advised Dr. Saldana.

Long-term Outlook

Joint hypermobility tends to decrease with aging as people become naturally less flexible and less active. However, some young adults may continue to experience joint pain or other symptoms related to weaknesses in the connective tissues throughout their body. These can include digestive system problems, headaches, dizziness, heart palpitations, sweating and anxiety. To properly manage their condition, Dr. Saldana recommends that these patients include other specialists such as a primary care physician and rheumatologist as part of their care team.

Tags: children's health, Miami Orthopedics & Sports Medicine Institute