Purpose: Use of six-axis analysis and computer assisted deformity correction via a circular external fixator is a new method for deformity correction. We investigated its accuracy and safety in reconstruction of femoral deformity in children and young adults.

Method: We retrospectively reviewed all cases including the indications for use and the methodology of application of the computer assisted six-axis analysis and circular external fixator for reconstruction of 22 femora in 20 patients. Twelve patients were female, and 8 were male. The average age was 13.9 (range, 5.9–24.6). Etiology included traumatic (7), idiopathic (6), multiple enchondromatosis (2), rickets (2), congenital femoral deficiency (2), spondyloepiphyseal dysplasia (1), congenital pseudohypoparathyroidisim (1), and multifocal osteomyelitis (1). Clinical and radiographic data were analyzed.

Results: Average follow-up was 14.4 months (range, 4.5–32). Average time in frame was 6.2 months (range, 2.6–19). Bone lengthening of 3.9 cm (range, 1–8.5) was performed in 12 femora. In genu valgum patients, the mLDFA improved from a mean of 73.7° to a mean of 89°. In genu varum patients, the mLDFA improved from a mean of 99.8° to a mean of 89.5°. Complications included pin tract infection in 6, knee stiffness in 3, delayed union in 2, skin irritation in 1, posterior knee subluxation in 2, both of which had stable knees preoperatively. One patient was lost to follow-up and returned back with deformity. No complications occurred in 8 patients.

Conclusion: Computer assisted femoral deformity correction with six-axis analysis and application of circular external fixator is a useful technique with the advantage of managing multiplanar deformities in children and young adults. It has the potential complications of the use of any external fixator. Close follow-up is necessary to avoid subluxation of the knee joint even in patients with stable knees. Accurate and safe correction can be achieved in almost all patients.

Purpose: Despite advances in surgical technique, neurological injury remains a potentially devastating complication of spinal deformity correction surgery. The purpose of the study is to describe surgical and patient factors associated with “electrophysiologic (EP) events” and neurogenic deficits.

Method: A retrospective chart review, looking at “EP events” during surgery, was conducted on 162 patients who received surgical treatment of their pediatric spine deformity from 1999 to 2004.

Results: Ninety three percent of cases (n=151) were successfully monitored by either somatosensory evoked potential (SEP) or motor evoked potential (MEP) monitoring. All three neurologic deficits that occurred in this study cases were successfully detected by EP monitoring (0.02%, p=.002). In those 151 cases that were successfully monitored, “EP events” were occured in twenty (13.2%) cases. The most common cause was systemic change (45%) and curve correction (40%). In those 20 cases, when corrective actions were made (n=15) “EP events” reversed to baseline values in all cases. When no corrective actions were taken (N=5) there was no reversals of “EP events” to baseline. Patients with kyphosis had a trend toward significantly higher rates of “EP events” (p=.174) and patients who had cardiopulmonary comorbidities had significantly higher rates of “EP events” (p=.007).

Conclusion: Consistent with existing literature, the EP monitoring was successful in the vast majority of deformity surgeries. “EP events” were able to be reversed with corrective action and to predict neurologic deficits. Our study found that patients with kyphosis and/or cardiopulmonary comorbidities have higher risk of significant “EP events” during the surgeries.

Purpose: To describe the clinical outcomes of adolescent patients, treated with hip distraction arthroplasty for avascular necrosis (AVN) of the femoral head. Outcomes were examined in order to better understand the usefulness and indications of performing hip arthrodia-stasis in this patient population.

Method: Retrospective review was performed on thirty-one hips with femoral head AVN treated with hip distraction arthroplasty. Mean age at treatment was 14.2 years. Preoperative and follow-up pain, and physical limitations, as well as follow-up range of motion (ROM) were assessed.

Results: Follow up assessment was obtained at 18.3 years of age. Time of follow up was 55.3 months after distraction. The etiologies of AVN were: 11 Slipped Capital Femoral Epyphysis (SCFE); 5 Idiopathic AVN; 3 with hip dysplasia; and 12 others. There was a significant difference in pain preoperatively and postoperatively (p< .001), the majority of patients (79.5%, n=23) had less pain after the treatment. Multivariate regression model demonstrated that patients with SCFE were likely to have less improvement in pain than patients with other etiologies (odds ratio: 24.8; p=.035). All patients had activity limitations before the treatment; at the postoperative assessment more than half of our patients (n=15) reported no limitations in their activities. Nine patients had minor complications with the fixator. At follow up, 5 (16.1 %) patients converted to total hip replacement or arthrodesis.

Conclusion: Hip distraction arthroplasty in adolescent patients with symptomatic AVN reduces the amount of pain and limitation in daily activities, at a follow up of 4.6 years. Arthrodiastasis is not the final solution to AVN, with longer follow up patient’s symptomatology increases. Patients with AVN secondary to SCFE do not beneficiate of this procedure as much as other patients do. Hip distraction is a safe and appropriate procedure to perform in these patients. The procedure might be able to delay definitive surgical procedures at an early age, restoring function and improving the patient s quality of life.

Purpose: The current literature lacks a truly comprehensive examination of the use of a valgus osteotomy to treat osteonecrosis of the femoral head and Perthes disease in the pediatric and adolescent population. Owing to the severity of the pathology, a retrospective examination of the success of valgus osteotomies in treating avascular necrosis and Perthes disease in children and adolescents is warranted.

Method: Twenty-four patients with diagnosis of osteo-necrosis of the femoral head or Perthes disease treated between 1995 and 2007 with a proximal femoral valgus osteotomy were identified. The causes of avascular necrosis were Perthes (N=14, 60.9%), slipped capital femoral epiphyses, (N=4, 17.4%), femoral neck fracture (N=2, 8.7%), hip septic arthritis (N=2, 8.7%) and developmental delays and idiopathic osteonecrosis (N=1, 4.3%). The average age of receiving a femoral valgus osteotomy was 10± 3.6 years. The average age at follow-up was 12.2± 4 years, mean time of follow-up from the initial valgus osteotomy to last assessment was 23± 15.3 months.

Results: Postoperative pain improved significantly compared to preoperative pain (p=.002). Seventy five percent of patients (n=9) who had limitations in their daily activities preoperatively reported that they no longer experienced them after the treatment. External rotation (p=.005) and abduction (p=.003) improved significantly at follow up. Postoperative Ficat & Arlet classification was significantly better when compared to the classification before valgus osteotomy (p=0.007). Univariate analysis showed that sixty percent of patients (n=6) who had Perthes had improved in their Ficat & Arlet stage whereas one (14.3%) patient with a different diagnosis improved (p=.082). Complications from the surgery were reported in 5 of the 23 (21.7%) cases.

Conclusion: The results of this study suggest that proximal femoral valgus osteotomy is a safe and effective treatment method for osteonecrosis of the femoral head in the pediatric population. Perthes patients improved their femoral head shape more than all other etiologies; there was a trend toward statistical significance in this change. Proximal femoral valgus osteotomy may improve pain and activity limitations in children with osteonecrosis of the femoral head. It is also effective at improving range of motion and femoral head x-ray appearance of the femoral head for these children.