Pedicle subtraction osteotomy using ultrasonic bone curette yields fewer durotomies, decreased blood loss: a single surgeon's retrospective experience.

Background: Pedicle subtraction osteotomy (PSO) is a three column deformity correction technique that can achieve 30 to 40 degrees of correction and is best used for patients with severe rigid sagittal imbalances. Patients report a high degree of satisfaction with quality of life outcomes as a consequence of undergoing PSO. However, complications range between 12% and 40%, including dural tears or neurovascular injuries causing neurological deficit occurring as a consequence of high speed drilling or traction from the spooned retractors used to facilitate exposure. Ultrasonic bone curettes may provide a safer alternative to the drill and retractor approach. The purpose of this retrospective study was to compare outcomes between newer spoonless ultrasonic bone curettage and traditional high speed drilling with paravertebral spoon retractors for pedicle subtraction osteotomies. Methods: All patients undergoing PSO with a single surgeon across two academic health institutions in the past eight years were reviewed. Preoperative variables obtained were demographics, prior spine surgeries, and etiology, while intraoperative predictor variables were ultrasonic bone curettage use and number of fused levels. The principal outcomes were surgical: duration of surgery, estimated blood loss (EBL), incidence of durotomies, and neurovascular injury. Secondary outcomes were postoperative: length of stay, need for revision surgery, minor complications, and major complications. Multiple logistic regression was used to evaluate associations with binary outcomes, while multiple linear regression evaluated correlations with continuous outcomes. Results: Overall, 175 patients were reviewed. In this sample, 89 (51%) had prior surgeries, and 45 (26%) were treated with the ultrasonic bone curettage. Intraoperatively, the mean EBL was 1,105 mL (range, 350-3,000 mL), 29 (17%) of participants sustained durotomies, 14 (8%) experienced neurovascular injury, and the mean duration of surgery was 401 mins (range, 135-695 mins). Postoperatively, 35 (20%) experienced minor complications, 25 (14%) experienced major complications, and mean length of stay was 11 days (range, 2-80 days). Ultrasonic bone curettage use correlated with decreased blood loss (β =-270 mL, P=0.004) and was associated with decreased incidence of durotomy [odds ratio (OR) =0.29, P=0.042]. Conclusions: Use of spoonless ultrasonic bone curettage in PSO was associated with significantly less blood loss and fewer durotomies compared to traditional drilling in this single surgeon's multi-institutional experience.