OBJECTIVE: This study looked into whether crossbar can reliably measure Upper Instrumend Vertebra (UIV) tilt angle intraoperatively and accurately predict the UIV tilt angle postoperatively and at final follow-up.
SUMMARY OF BACKGROUND DATA: Postoperative shoulder imbalance is a common cause of poor cosmetic appearance leading to patient dissatisfaction. There were no reports describing the technique or method in measuring the UIV tilt angle intraoperatively. Therefore, this study was designed to look into the reliability and accuracy of the usage of intraoperative crossbar in measuring the UIV tilt angle intraoperatively.
METHODS: Lenke 1 and 2 Adolescent Idiopathic Scoliosis patients who underwent instrumented Posterior Spinal Fusion using pedicle screw constructs with minimum follow-up of 24 months were recruited for this study. After surgical correction, intraoperative UIV tilt angle was measured using a crossbar. Immediate postoperative and final follow up UIV tilt angle was measured on the standing anteroposterior radiographs.
RESULTS: A total of 100 patients were included into this study. The reliability of the intraoperative crossbar to measure the optimal UIV tilt angle intraoperatively was determined by repeated measurements by assessors and measurement by different assessors. We found that the intra observer and inter observer reliability was very good with intraclass correlation coefficient values of >0.9. The accuracy of the intraoperative crossbar to measure the optimal UIV tilt angle intraoperatively was determined by comparing this measurement with the postoperative UIV tilt angle. We found that there was no significant difference (P>0.05) between intraoperative, immediate postoperative, and follow-up UIV tilt angle.
CONCLUSIONS: The crossbar can be used to measure the intraoperative UIV tilt angle consistently and was able to predict the postoperative UIV tilt angle. It was a cheap, simple, reliable, and accurate instrument to measure the intraoperative UIV tilt angle.
OBJECTIVE: The primary objective of this study was to assess the conformity of the radiological neck and shoulder balance parameters throughout a follow-up period of more than 2 years.
SUMMARY OF BACKGROUND DATA: Postoperative shoulder and neck imbalance are undesirable features among Adolescent Idiopathic Scoliosis patients who underwent Posterior Spinal Fusion. There are many clinical and radiological parameters used to assess this clinical outcome. However, we do not know whether these radiological parameters conform throughout the entire follow-up period.
METHODS: This was a retrospective study done in a single academic institution. Inclusion criteria were patients with scoliosis who underwent posterior instrumented spinal fusion with pedicle screw fixation and attended all scheduled follow-ups for at least 24 months postoperatively. Radiological shoulder parameters were measured from both preoperative antero-posterior and postoperative antero-posterior radiographs. Lateral shoulder parameters were: Radiographic Shoulder Height, Clavicle Angle (Cla-A), Clavicle-Rib Intersection Difference, and Coracoid Height Difference. Medial shoulder and neck parameters were: T1 Tilt and Cervical Axis (CA).
RESULTS: The radiographs of 50 patients who had surgery done from November 2013 to November 2015 were analyzed. Mean age of this cohort was 16.3 ± 7.0 years. There were 38 (76%) female patients and 12 (24%) male patients. Mean final follow-up was 38.6 ± 5.8 months. When conformity assessment of the radiological parameter using the interclass coefficient correlation was done, we found that all parameters had significant correlation (P