Prospective Trial to Evaluate Initial Safety of the HemiBridge™ System in Guided Spinal Growth Treatment of Progressive Idiopathic Scoliosis

Significance Spinal deformity fusion treatment involves some of the most costly and invasive procedures in orthopaedics. The development of an effective treatment method to avoid fusion is needed. Many pediatric spine specialists concur that growth modulation displays compelling pre-clinical and clinical data that must be studied further. While bracing is the only non-operative modality with any evidence of effectiveness for idiopathic scoliosis, its level of effectiveness compared to observation or natural history remains inconclusive. Research has been published for over 50 years, yet conflicting literature reports both successes and failures. Most literature consists of retrospective reports of bracing experience, with little commonality relative to existing conditions at the time bracing is initiated, documentation of compliance and basis for judging success.

The U.S. Preventative Services Task Force (USPSTF) is an independent panel of private-sector experts in primary care and prevention. The Task Force was convened by the U.S. Public Health Service to systematically review the evidence of effectiveness of clinical preventive services. One of their charges was to evaluate the evidence supporting the practice of school screening for adolescent idiopathic scoliosis. After systematically reviewing the literature to date, their policy statement issues in 1992, and updated in 1996 states "...There is inadequate evidence to determine whether brace therapy limits the natural progression of the disease in a significant proportion of cases, as most studies suffer from selection bias, lack of internal control groups, inadequate follow-up, small sample sizes, and lack of health outcome measures."

There is no Level One evidence to support the practice of bracing, and clinicians are left with conflicting and questionable inferences regarding bracing effectiveness. Some clinicians believe the evidence favors a decrease in the rate of curve progression, and based on this assumption, over half the states in the U.S. have mandated school screening programs for the detection and early treatment of scoliosis. On the other hand, groups such as the USPSTF, its British and Canadian counterparts and many individual practitioners worldwide feel the evidence is inconclusive and are therefore ambivalent about brace treatment.

Due to the variability in published results on brace effectiveness, researchers in the United States and Canada have commenced a randomized multi-center trial of bracing versus no bracing to determine the effectiveness of brace wear in the treatment of idiopathic scoliosis (BRAIST Study). This study, which was initiated in 2007 in the United States, is being performed under the auspices of the US National Institutes of Health (NIH) and Canadian Institute of Health. In the Netherlands, a randomized multi-center study comparing bracing to observation is also underway.

While bracing treatment is non-invasive and preserves growth, motion and function of the spine, it does not correct the deformity. In addition, the brace pressure on the rib cage and the influence on the chest wall in a growing child create concerns. Some scoliosis patients wear a brace for as long as five years only to learn that brace treatment failed and then recommended to endure major fusion surgery and recovery.