Complications in Adult Patients with Down Syndrome Undergoing Cervical Spine Surgery Using Current Instrumentation Techniques and rhBMP-2: A Long-Term Follow-Up.

Abstract

Introduction Cervical spine pathologies are common in Down syndrome (DS) patients. Cervical pathologies may cause cord compression and neurologic deterioration if left untreated. Complication rates of 73-100% have been reported in DS patients after cervical spine surgery in historical studies. This study reports updated perioperative complications rates and long-term outcome in patients with DS undergoing cervical spine surgery. Methods Retrospective review of patients with DS who have undergone cervical spine surgery from 1998 to 2011 (≥ 24 months of follow-up) was undertaken. Series of 17 adults with preoperative diagnoses that included atlantoaxial instability, stenosis, spondylosis, or cervical spondylolisthesis were evaluated. Nine patients received recombinant human bone morphogenetic protein-2 (rhBMP-2). Neurologic and ambulatory status was evaluated at regular intervals included pre- and postoperative imaging, range of motion evaluation, strength/neurologic testing, ambulation observation, and patient and caretaker pain reporting. Results A total of 20 surgical procedures were performed in 17 patients. Average follow-up was 78.7 months (range: 25-156 months). Overall, 37 complications were observed including pneumonia, respiratory distress, reintubation, dysphagia, deep venous thrombosis, sepsis, wound infection, dehiscence, neurologic complications, loss of reduction (LOR), pseudarthrosis, and hardware failure. Postoperative pneumonia was most common (23.5%). Three patients developed pseudarthrosis (all in the rhBMP-2 group); three demonstrated LOR. Neurologic complications (N = 3) included spasticity, loss of ambulation, and postoperative weakness with myelomalacia. Two were transient. Respiratory complications in the rhBMP-2 group were the most common (N = 3). The anterior approach resulted in a higher likelihood of complications than the posterior (p = 0.032). Conclusions Current techniques may improve pseudarthrosis (p = 0.009), LOR (p = 0.043), and first attempt (p = 0.038) and overall fusion rates (p = 0.018) compared with historical studies. Complications continue to challenge most patients (82.4%). A total of 16 of 17 patients (94.1%) demonstrated stabilization or improvement in neurologic status. Apparent successful outcome in the majority appears to warrant the high complication risk associated with cervical spine surgery in DS patients. The anterior approach resulted in a higher risk of complications than posterior (p = 0.032). We report a higher than expected incidence of pseudarthrosis in DS patients receiving rhBMP-2, putting its benefit in DS patients into question.