Comparison of Functional Outcomes and Sagittal Balance in Adolescent Idiopathic Scoliosis Corrective Surgery...

Adolescent idiopathic scoliosis (AIS) is a three-dimensional spinal deformity that arises in otherwise healthy children. Surgical correction for patients with a Cobb angle is usually performed with posterior corrective surgery utilizing rods bent intraoperatively. With the invention of patient-specific rods (PSR), we compared the radiological and functional outcomes of patients operated on with either rod.

A retrospective cohort study in which AIS patients who underwent posterior corrective surgery from April 2019 until March 2021 in two state hospitals were recruited. They were divided into two groups based on the rods utilized: PSR and conventional rod (CR). Radiographic evaluation of sagittal vertical axis (SVA), pelvic tilt (PT), and pelvic incidence-lumbar lordosis mismatch (PI-LL) parameters was recorded before and three months after the operation. Surgeries were performed with the aim of achieving SVA <50 mm, PT<20°, and PI-LL<10°. Patients were interviewed using SRS-30 questionnaires six months postoperatively to compare the functional outcome.

Thirty-three patients were recruited; 18 were in the PSR group, and 15 were in the CR group. Pre- and postoperative PI-LL change in the CR group is significant (p<0.05). Comparison of mean difference showed that only the PI-LL difference is significant between PSR and CR (p<0.05). The PSR group showed a higher percentage of achieving planned correction in all three parameters, with 13 patients (72.22%) in PI-LL, 94.44% in PT, and 17 patients (94.44%) in SVA. In the CR group, only SVA had a higher percentage of patients able to achieve planned sagittal parameters. Both groups produced comparable functional outcome scores, with a total average of 4.36 for PSR and 4.47 for CR, out of a maximum of 5.

PSR can achieve better planned sagittal parameters compared with CR clinically. Both PSR and CR groups showed comparable functional outcomes.