Most long-term follow-up studies report retrospective data, the quality of which remains limited due to their inherent biases. Prospective databases may overcome these limitations, however, feasibility and costs limit their application. To date there exists a paucity of evidence-based literature on which recommendations can be made for the ideal length of follow-up for spinal deformity research. Therefore, our aim was to evaluate the added value of follow-up of patients beyond 2 years following surgery for AIS.

A database registry evaluating surgical outcomes for all consecutive AIS patients with post-op data-points of 6 months, 1 year, 2 year, and 5 year was analysed. Surgeon-reported complications, SRS-22 scores, and radiographic data were evaluated. Complications requiring surgical or medical intervention were compared between patients in whom complications developed within 2 years to those in which newly developed complications occurred between >2–5 years.

536 patients were analysed. SRS-22 scores significantly improved at 2 years post-op with no change at 5-year follow-up. Overall complication rate was 33.2% with majority occurring within 2 years (24.8%). The rate of complications occurring >2–5 years requiring intervention was significantly lower than those requiring intervention within 2 years of surgery (4.7% vs 9.7%, p=0.000), however was not negligible. The most common newly observed complication beyond 2 years was pain (1.9%), followed by surgical site infection (SSI) (1.3%) and implant issues (0.56%). There were no significant differences in the rates of crankshaft (p=0.48), implant issues (p=0.56), pseudarthrosis (p=0.19), and SSI (p=0.13) between the 2 time points.

Although majority of complications following AIS surgery occurs within 2 years, a non-negligible rate of newly observed complications occur at >2–5 years post-op. Specifically crankshaft, pseudarthrosis, implant issues, and SSI have similar rates of occurrence at these 2 time points.

Natural history of AIS >30° in skeletally mature patients is poorly defined. Studies reporting rates and risk factors for progression are predominantly of large curves in immature patients. Our aim was to determine the rate of curve progression in AIS following skeletal maturity, any associated changes in SRS-22 scores, and identify any potential predictors of curve progression.

Patients enrolled in a prospective, longitudinal, multicentre non-surgical AIS database were evaluated. All patients had minimum 2 year follow-up, idiopathic scoliosis >30°, and were skeletally mature. SRS-22 functional outcome scores and radiographic data were compared at baseline and 2-year follow-up. Patients were divided into 3 groups based on curve size: A=30°-39°, B=40°-49°, C= >50°. Curve progression was defined as any change in curve magnitude.

There were 80 patients, majority females (93.8%) with a mean age of 16.5+/−0.16. Mean BMI was 21+/−0.31 with 15.1% overweight. Mean major cobb at baseline was 38.3°+/−0.88°. At 2 year follow-up 46.3% of curves had progressed an average 3.4°+/−0.38°. Of curves that progressed, patients in group A had the largest mean rate of progression followed by group B. SRS-22 scores on average declined significantly over 2 years in this cohort (4.23 to 4.08; p=0.002). Patients who progressed had on average a more significant decline in SRS outcome scores compared to those that did not (p=0.018, p=0.041 respectively), with the most significant change noted in the Self-Image domain (p=0.03). There was no significant difference in the change in SRS scores over 2 years based on curve size. Univariate analysis did not identify any factors predictive of curve progression in this cohort.

Skeletally mature patients with AIS >30°may continue to have a risk of progression at a mean rate of 1.7°/yr and significant decline in SRS-22 outcome scores, in particular Pain and Self-Image, over time.

Introduction

Pedicle screw fixation commonly uses a manual probe technique for preparation and insertion of the screw. However, the accuracy of obtaining a centrally located path using the probe is often dependent on the experience of the surgeon and may lead to increased complications. Fluoroscopy and navigation assistance improves accuracy but may expose the patient and surgeon to excessive radiation. DSG measures electrical conductivity at the tip and provides the surgeon with real-time audio and visual feedback based on differences in tissue density between cortical and cancellous bone and soft tissue. The authors investigated the effectiveness of DSG for training residents on safe placement of pedicle screws.

Background: To present the experience of three centres in the surgical management of scoliosis in patients with Prader-Willi syndrome¹, and to describe the associated complications. A retrospective case series reviewing treatment type, surgical outcomes and complications with a review of the literature

Methods: There were 15 patients treated surgically in the three centres over an eleven year period. The average age at initial surgery was 9.6 (5 to 16+8) yrs. Minimum follow-up from index procedure was 28 months. 5 underwent posterior spinal fusion, 2 had anterior fusion alone and 2 had combined anterior/ posterior fusions as their index procedure. 6 patients were initially managed with growing rod constructs. Outcome measures included fusion rate, curve progression and complication rate.

Results: 11 patients achieved a solid fusion. 2 patients were still undergoing the lengthening process and were thus unfused. 1 patient had broken instrumentation with pseudarthrosis, and one patient not fit for final fusion remained without implants. No curve progression was seen in the 11 fused spines. Progressive kyphosis and scoliosis were noted in the two ongoing lengthening patients. There were 17 revision procedures not including planned lengthenings, with a total of 59 surgical procedures. 5 rod breakages occurred in the growing-rod patients. There were 11 infections (4 deep) in 7 patients. There were 6 respiratory complications, 3 requiring ventilatory support. One patient had post-operative neurological deterioration requiring re-exploration and who had grade 3 paraparesis at final follow-up. In total there were 36 complications (240%)

Conclusion: The outcome of surgical management of scoliosis in Prader-Willi syndrome is adversely affected by the obesity and respiratory difficulties of the patients and complications abound². The use of growing constructs, whilst enabling the management of the growing child, greatly increases the risk of implant failures. Their use in Prader-Willi requires careful consideration.