Growth Guidance Surgery: Factors Associated With Complications

Retrospective, multicenter cohort study.

Growth guidance surgery (GGS) has lower reoperation rates and fewer episodes of care than other growth-sparing methods but is associated with instrumentation complications. This study aimed to characterize factors associated with implant complications in GGS.

A multicenter early-onset scoliosis database was analyzed for patients who underwent GGS. Radiographs, complication reports, and reoperation notes were evaluated for instances of rod breakage, screw pullout, instrumentation prominence, skin breakdown over implants, patients outgrowing implants, and deep wound infection. Descriptive statistics, χ 2 test, and Cox proportional-hazards models were utilized to detect differences in complications.

One hundred eighteen patients [7±2 y old; 69 (58%) female] were included. Mean follow-up was 5 (±3) years. The 173 instances of instrumentation complications comprised 55 (32%) broken rods, 46 (27%) screw pullouts, 33 (19%) prominences, seven (4%) skin breakdown over implant, and 32 (18%) outgrowing the rods. There was a 2.46-fold ( P =0.039) increased risk of rod breakage for rod diameter ≤4.5 versus >4.5 mm. For lighter patients, odds were greater for screw pullout by 2.0-fold, for prominence by 3.1-fold, for skin breakdown over implant by 7.7-fold, and for deep wound infection by 3.6-fold compared with heavier patients (all P <0.05). Broken rods more often occurred within two vertebrae of the apex of deformity; screw pullouts near the upper or lowest instrumented vertebrae.

Most instrumentation failures were broken rods and screw pullouts. Breakage was largely confined to the deformity apex and was mitigated by rods >4.5 mm; pullouts clustered at construct ends. Lighter ( i.e. mostly younger) patients faced higher risks of infection, prominence, and skin compromise. Using larger-diameter rods, ensuring robust proximal-distal fixation, and maximizing the muscle envelope may meaningfully reduce these complications and, thus, reoperations.

Level III.