Does the presence of dystrophic features in patients with type 1 neurofibromatosis and spinal deformities increase the risk of surgery?

STUDY DESIGN: Retrospective chart and radiographical review. OBJECTIVE: To present the demographics of patients with scoliosis and neurofibromatosis type 1 (NF-1), to record the incidence of dystrophic features, and to determine whether the presence of dystrophic features increase the risk of surgery in patients with NF-1 and associated spinal pathology. SUMMARY OF BACKGROUND DATA: The most common of the osseous complications of NF-1 is spinal deformity, occurring in 10% to 30% of individuals with NF-1. Many of these patients will eventually require surgery for curve progression, which makes study of demographics and identification of features predicting the need for surgery essential in this patient population. METHODS: A retrospective review was performed in patients with NF-1 and spinal deformities, followed in a multidisciplinary neurofibromatosis center. A subset of 56 patients with complete radiographical evaluation was reviewed for identification of risk factors for spine surgery. RESULTS: One hundred thirty-one patients from a population of 694 patients with NF-1 (19%) had scoliosis. Mean age at diagnosis of scoliosis was 9 years (range; 1-17 yr). Scoliosis and need for surgery were equally distributed between males and females. In the group of 56 patients, 63% had 3 or more dystrophic features. The presence of 3 or more dystrophic features was the strongest predictor of the need for surgery (odds ratio = 14.34; P < 0.001). Individual features most predictive of need for surgery were the presence of vertebral scalloping (odds ratio = 13.19; P < 0.001) followed by the presence of dural ectasia (odds ratio = 6.38; P = 0.005). Patients with no dystrophic features were unlikely to progress to need for surgery. CONCLUSION: Scoliosis and need for surgery were equally distributed between males and females. The presence of 3 or more dystrophic features was highly predictive of the need for surgery, with the most significant individual predictors being vertebral scalloping and dural ectasia. A combination of radiographical and MRI features can be used to predict need for spinal surgery. LEVEL OF EVIDENCE: 3.

Correction of spine deformity in patients with Melnick-needles syndrome: report of 2 cases and literature review.

BACKGROUND: Melnick-Needles syndrome (MNS) is a rare X-linked dominant disorder affecting the skeletal system and connective tissue. To date, < 70 cases with MNS have been documented. Although few reports in the literature have shown that these patients might develop kyphoscoliosis, there is no report regarding long-term follow-up of patients with MNS undergo spine surgery. The aim of this study is to describe 2 unique cases of MNS with long-term follow-up after instrumented posterior spinal fusion, multiple-level Ponte osteotomies, and pedicle subtraction osteotomies. METHODS: A 17-year-old female patient (patient 1) was evaluated for the first time at our institution. She was diagnosed with MNS, severe kyphoscoliosis, and restrictive lung disease. After pulmonary function improvement, she underwent posterior spinal fusion. Halo-femoral traction with gradual weight increase was used a week before spinal surgery. Surgical correction of her spinal deformity was achieved through a hooks-and-wires construct. The second patient was an 18-year-old female (patient 2) who carried the diagnosis of MNS when she was first seen at our institution. She had a significant thoracolumbar junction kyphosis and gibbous. She also suffered from significant pulmonary disease with a stent in her right main stem bronchus. A posterior procedure consisting of multiple-level Ponte osteotomies and pedicle subtraction osteotomy at L2 was carried out. RESULTS: Eight- and 5-year follow-up of patients 1 and 2, respectively, demonstrated solid fusion, a well-maintained correction, and no evidence of implant breakage. CONCLUSIONS: The reported cases add to the literature of excellent long-term results of spinal deformity correction with instrumented posterior spinal fusion in patients with MNS. Patients with this condition should be closely monitored from early childhood for the development of spine deformity so that early referral to a spine surgeon can be made followed by appropriate treatment, if necessary.

New orthopedic devices and the FDA.

Each year the field of orthopedics is introduced to an influx of new medical devices. Each of these medical devices has faced certain hurdles prior to being approved for marketing by the U.S. Food and Drug Administration (FDA). Among the regulatory pathways available, the 510(k) premarket notification is by far the one most commonly used. The 510(k) premarket notification allows the manufacturer to receive prompt approval of their device by demonstrating that it is "substantially equivalent" to an existing legally marketed device. In most instances, this proof of substantial equivalence allows manufacturers of medical devices to bypass the use of clinical trials, which are a hallmark of the approval process for new drugs. As a result, most medical devices are approved without demonstrating safety or effectiveness. This article reviews the regulatory processes used by the FDA to evaluate new orthopedic devices.