** POSTERIOR HEMIVERTEBRA RESECTION IN CONGENITAL SCOLIOSIS – A NEW OPERATIVE TECHNIQUE AND FIRST RESULTS

Michael Ruf, MD;
Jürgen Harms, MD
Karisbad, Germany

Congenital scoliosis caused by hemivertebra is a potentially rapidly progressive deformity, which often causes severe deformity especially during growth spurt. Therefore therapy should start as early as possible to allow the spine a nearly normal growth and to avoid secondary structural changes. Following this aspect we developed since 1991 a new operative technique of a posterior only resection of hemivertebra with instrumentation by transpedicular screws. The technique is particularly suitable in very young children for earliest correction.

Approaching the spine from posterior we remove the posterior elements of the hemivertebra, i.e. the lamina, the transverse process and the posterior part of the pedicle. Under microscopical control the anterior part of the pedicle and the body of the hemivertebra are resected in an eggshell–like procedure. The cartilage of the adjacent endplates is removed, then the pedicle screws are placed in the adjacent vertebrae and compression is applied at the convex side. Cancellous bone is added for bony fusion.

From 1991 to 1999 we performed this procedure in 30 hemivertebrae in 28 patients. The mean age at operation was 7+3 (yrs.+mos.), range 1+3 to 17+11, the average follow up was 26 month (4 to 104 month). Cobb angle of the primary curve (with hemivertebra) was average 43.0 degrees (range 9 to 75 degrees) and improved postoperative to 14.0 degrees (–l to 40). Cobb angle at last follow up was 16.3 degrees (–2 to 59). Kyphosis angle improved from 23.7 degrees (2 to 54) to 10.6 degrees (–7 to 32), follow up 10.5 degrees (–5 to 29). There were no major complications, especially no persisting neurological deficit. Looking at the effect of pedicle screws in the growing child we found no narrowing of the spinal canal.

In summary, posterior resection of hemivertebrae followed by segmental instrumentation is a safe and efficient procedure, thus limiting the extent of spinal fusion and allowing an almost normal growth. We advocate to perform this operation method especially in toddlers and very young children for earliest correction. However, thorough follow–up is mandatory until the end of bone growth in order to recognize subsequent deformities, i.e. scoliosis or kyphosis, and in order to react by further operative intervention if necessary.

** The FDA has not cleared a drug and/or medical device for the use described in this presentation. (i.e., the drug or medical device is being discussed in an “off–label: use).