Indirect pars repair for pediatric isthmic spondylolysis: a case series

Isthmic spondylolysis (ISY) is a common cause of back pain in the pediatric population. Historically, non-operative treatments have had a very high success rate. The purpose of this study was to review the mid-term results of an indirect pars repair technique on reducing the visual analog score for pain (VAS), spondylolysis defect healing, complication rates and rates of return to pre-surgery activity level in pediatric patients who failed conservative care for ISY.

A retrospective review of all pediatric patients (<18 years old) treated surgically by one surgeon over a 5-year period was performed. Patients were treated with indirect pars repair utilizing pedicle screws and laminar hooks and local autograft. Preoperative VAS was compared to the final follow-up score, and return to activity was evaluated. Radiographs were reviewed to evaluate healing.

Nine patients (6 females, 3 males) were treated surgically. Average age at the time of surgery was 15.4 years, (range, 13 to 17 years). Average length of final follow-up was 11.9 months (range, 6 to 24 months). Preoperative VAS averaged 5.6 points (range, 2 to 8 points) compared to final follow-up of 1.2 (range, 0 to 3). Definitive bony healing was noted in 7 of 9 cases (77.8%) with at least 6 months follow-up. Eight of nine patients (88.9%) returned to preoperative competitive sports activity level. No complications were noted during the follow-up period.

Pediatric patients treated surgically with indirect pars repair appear to achieve satisfactory mid-term outcomes. This technique appears safe, and has both a high healing rate and return to competitive athletics. Further study is needed to determine durability of this procedure.