High tibial valgus osteotomy is now well established in management of medial knee osteoarthritis. While conventional closing osteotomies are usually within 2 cm of the knee joint, opening wedges typically pivot more distally from the joint line; theoretically the same angular correction will cause greater linear shift of the tibial plateau away from the tibial long axis. We hypothesise that this may lead to an increased incidence of problems with future knee replacement where tibial stem augments are needed, and to evaluate this we used a computerbased templating system with web-based component templates for sizing and implant position planning.

We studied 10 knees that had undergone opening wedge osteotomy. Pre-operative and postoperative mechanical and anatomical axes, and corrections achieved, were measured radiologically. Computer-based knee arthroplasty templating was then performed with the TraumaCad digital templating software (Orthocrat, Israel), using Depuy PFC tibial component templates with 75 mm stem augments. Cases were analysed for impingement of tibial stem augments when added to a well-placed tibial tray, and conversely for the need for tibial tray downsizing to avoid tray overhang if stem augments were placed centrally.

Results: Mean pre-operative mechanical axis was 10.6o varus (1.6o to 22.3o). Mean osteotomy to joint line distance was 25.7mm (21.0mm to 33.1mm). In four knees, the addition of a 75 mm tibial stem augment to a well-placed tibial component caused stem impingement on cortex. In these four cases, central placement of the stem augment in the canal led to medialisation of the tibial component, necessitating downsizing of tibial tray by one to two sizes to avoid medial overhang and resulting in sub-optimal coverage of the cut tibia. These four cases all had valgus corrections of over 11o (11.5o to 19.6o). Conversely the six cases that did not have impingement or sizing problems all had corrections under 9o (3.0o to 8.2o). Our early results suggest that higher degrees of valgus correction with opening wedge osteotomy may lead to problems with future knee replacements requiring tibial stem augments. We are in the process of recruiting more cases to determine threshold levels for different makes and models of implants, using the same templating software system.

Video-assisted thoracoscopic surgery (VATS) has been in use since the 1980s for surgery of the spine. Initially it was used for anterior release of the thoracic spine in order to facilitate posterior instrumentation. With increasing experience, it has been applied to perform definitive correction and instrumentation. Video-assisted thoracoscopic spine surgery allows the surgeon to perform anterior thoracic spine operations with fewer levels of instrumentation, reducing the crankshaft effect and removing the morbidity associated with thoracotomy. From 1996 to November 2000, our center performed 19 such operations. 18 of them were completed successfully endoscopically and one was converted to an open procedure. An initial group of 10 patients underwent thoracoscopic anterior release and fusion followed by same day posterior instrumentation and fusion. Subsequently, 6 patients underwent anterior discectomies, fusion with instrumentation via thoracoscopic approach.

For the initial 10 patients, the average operative time was 190 minutes. The average post-operative correction was 62 % and blood loss was 350 mLs. For the 6 patients who underwent anterior discectomies, fusion and instrumentation via the thoracoscopic approach, the average operative time was 360 minutes; average post-operative correction was 70% and blood loss was 400 mLs.

Complications encountered were minor and included one case ofcontralateral pneumothorax, one patient complained of transient limb numbness which resolved within 6 weeks. It is our conclusion that thoracoscopic anterior spinal surgery, though with learning curve, a safe and effective procedure.

Introduction: Surgery in patients with neuromuscular scoliosis is aimed at improving truncal balance, facilitating sitting, prevention of progression of the curve and preservation of respiratory function.

Patients and Methods: This was a retrospective study of surgical results in a group of 24 patients with minimum follow up of 2 years an average post-operative follow up of 5 years (2–9 years) with neuromuscular scoliosis due to varying aetiologies. The aetiologies included SMA (7), CP (6), Duchenne (5), Congenital Myopathies (3), Spina Bifida (2) and Paraspinal Neuroblastoma (1).

Results: The average age at surgery was 10.6 years, the average duration was 4hrs 25mins with an average blood loss pf 1.1 liters. An average ICU stay was 1–2 days and stay in hospital is 11 days. The curves ranged from 25–103° (average 75.6°) pre-operative and we were able to obtain a correction of 56%. In all but 2 of our patients we were successful in preventing deterioration of respiratory function and all our patients could at least sit without support post-operatively. Our complications included only one deep infection (necessitating implant removal), 1 rod breakage and 2 patients with UTI. There were no significant respiratory complications in post-operation.

Conclusion: Spinal surgery in patients with neuromuscular scoliosis is safe and prevents deterioration of respiratory and improve truncal balance and hence quality of life.