A Multi-Center Prospecitve Study of 737 Questionnaires Utilizing the Scoliosis Research Society (SRS) Instrument for the Surgical Treatment of Adolescent Idiopathic Scoliosis

Andrew Merola,
Mario Brkaric,
Thomas Haher,
Thomas Lowe,
Larry Lenke,
Randal Betz,
Gail Huss,
Dennis Wenger,
Peter Newton,
David Clements,
Omid Kohani

INTRODUCTION:
The SRS instrument is a disease–specific, reliable, and validated questionnaire to assess outcomes in AIS. The SRS instrument was utilized prospectively to evaluate patient outcome measures in the surgical treatment of adolescent idiopathic scoliosis (AIS). The population included patients that underwent both anterior (n=322) and posterior (n=415) surgery. The instrument consists of 24 questions divided into seven equally weighted domains as determined by factor analysis: pain, general self–image, post–operative self–image, general function, overall level of activity, postoperative function, and satisfaction. The study was to compare SRS instrument scores in a large population of AIS patients having an anterior versus posterior instrumentation/fusion.

MATERIALS AND METHODS:
The questionnaire is administered preoperatively, and at 3, 6, 12, and >24 months postoperatively. The number of questionnaires completed at six centers was n=737. The questionnaires were scored and the comparisons made between groups, time periods, type of surgery, curve magnitude, and patient demographic data were analyzed for any statistical difference between and among groups.

RESULTS:
All patients showed a significant decrease in pre and post–op pain scores (two year follow–up, p<0.005). General self image scores improved significantly (pre–op 3.8, 2 yr. post–op 4.2, p<0.005). General function improved (pre–op 3.9, 3 yr. post–op 4.1, p<0.002). Under the satisfaction domain, the posterior group showed greater satisfaction than the anterior group with scores of 4.4/5 and 4.2/5 respectively. These scores were both considered positive responses though they were significantly different (p<0.05). There was no difference between the anterior and posterior groups in all other domains. Curve magnitude (above 508/below 508) had no effect on outcome in any domain.

CONCLUSION:
All patients treated surgically for AIS demonstrated significant improvement in all domains analyzed. Anterior surgery for AIS had outcomes that were not significantly different from posterior surgery except in the satisfaction domain, however the difference may not be clinically significant.