Surgery for idiopathic scoliosis with a Cobb angle of less than 40 degrees: results, questions and problems

Objective. To perform multicomponent assessment of the results of surgical treatment of patients with idiopathic scoliosis of less than 40° according to Cobb and their compliance with patients’ expectations.

Material and Methods. A total of 105 patients (97 women and 8 men) with an average age of 18.8 years, including 51 (48.6%) patients aged 18 years and older, were operated on for idiopathic scoliosis with a primary curve that did not exceed 40° (average 34.9°) at the time of surgery. Surgery was performed using Drummond instrumentation (2 patients), Antares system (4), and CDI (99), including using pedicle screws in 47 cases. The average period of postoperative follow-up was 51.1 months (range 24 to 170 months). Examination methods included clinical and radiological examination, SRS-24 questionnaire, and examination by a clinical psychologist.

Results. In the overall group of 105 patients, the primary curve decreased during the intervention from 34.9° to 11.6° (correction – 66.7%), and at the end of the observation period it was 14.1° (loss of correction – 10.7%). The countercurvature correction was 60.1% with a subsequent loss of correction of 1.1° (7.4% of the achieved correction). Transpedicular fixation resulted in significantly greater correction of the primary curve (24.7° vs. 21.7°) with a smaller loss of correction (0.7° vs. 5.4°). Survey using the SRS-24 questionnaire demonstrated significant positive trends in the overall score (the so-called Grand Total) and in the domains of general and professional activity. Negative trends were noted for the assessment domains of postoperative appearance and satisfaction with treatment results.

Conclusion. Idiopathic scoliosis with a primary curve less than 40° is often treated surgically due to patient’s demand. A significant proportion of patients are not fully satisfied with the outcome. Indications for surgery for such deformities should be formulated strictly on an individual basis, and patients require special preparation, primarily psychological.

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