Abstract
Posterior instrumented fusion is an established surgical treatment for majority of AIS cases. In the past decade, thoracoscopic instrumentation and fusion has emerged as a viable alternative to conventional posterior techniques in situations that require selective thoracic fusion. Most reports comparing the two techniques have focused on physician-based outcomes such as curve correction and maintenance of the surgical correction with both methods being comparable. Recently, the SRS-24 has been used to evaluate patient-based outcomes after scoliosis surgery. The instrument assesses seven equally-weighted domains that look at pain, self-image, general function, activity level, change in self-image and function post-surgery, and satisfaction with the procedure. It has been used to evaluate differences between AIS and normal patients, and in different degrees of AIS deformity. The instrument has not been used in comparing different methods of surgical treatment for similar curve types.
We applied the SRS-24 prospectively to our patients who had undergone either thoracoscopic (TG) or posterior (PG) instrumented fusion, and had been followed-up for at least 12-months postoperatively. There were 42 patients in TG and 42 patients in PG. The mean age at time of surgery, pre-operative Cobb angles, and number of spinal segments fused were similar in both groups. The mean follow-up period at the time the SRS instrument was administered was 26 (± 13.5) months for TG and 30.7 (± 12.1) months for PG. The postoperative Cobb angle on the latest follow-up was significantly better for TG compared to PG (17 versus 25.1 degrees, respectively; p < .001). Upon comparing the SRS domain scores between both groups, a significant difference was noted only in the patient satisfaction domain with TG scoring better than PG (p < .02).
The first four SRS-24 domain scores for TG and PG were also compared to the corresponding domain scores of 97 patients who had scoliosis but were not candidates for surgery (SG), as well as to the scores of 72 patients who did not have scoliosis (NG). SG, TG, and PG were comparable with regards to pain and all three were significantly lower compared to NG (F=14.828, p < .0001).
General function and activity level scores of TG were significantly lower compared to the other three groups (F=4.870, p < .003 and F=4.793, p < .003, respectively). Despite this, the self-image domain scores of both TG and PG were not significantly different from NG, with SG scoring significantly poorer compared to the other three groups (F=3.183, p < .02).
In summary, thoracoscopic instrumented fusion resulted in better curve correction compared to posterior instrumented fusion and was achieved with less spinal segments being fused. This was despite the finding that patients who underwent thoracoscopic surgery had lower physical function and activity level scores. Additionally, both surgical techniques resulted in patients whose perception of themselves was comparable to those patients who did not have scoliosis. The SRS-24 was not able to detect any differences between the two surgical methods in all domains except for overall patient satisfaction which was significantly better in the thoracoscopic group.
Correspondence should be addressed to Jeremy C T Fairbank at The Nuffield Orthopaedic Centre, Windmill Road, Headington, Oxford OX7 7LD, UK
