Surgically treated ischial tuberosity avulsion fractures in adolescents: Risks and outcomes of three fixation constructs

Philadelphia, PA

Background:

Avulsion fractures of the ischial tuberosity (AFIT) are uncommon injuries that sometimes require operative fixation for significant displacement and/or associated neurologic symptoms. Various fixation methods have been utilized, including screws, suture anchors, and cortical suspensory buttons. The purpose of this study is to review a consecutive series of surgically managed AFITs at a single institution and compare outcomes among fixation strategies. We hypothesized there would be no difference in outcomes between fixation types.

Methods:

We conducted a retrospective review of all patients treated operatively at a single institution from 2010-2022 for AFIT identified by CPT code (27215). We collected patient demographics, injury characteristics, Modified Oxford Score, radiographic measures, fracture classification (Type 1 -Lateral vs. Type 2 -Complete), surgical fixation technique (screw, suture anchor, and cortical suspensory button), postoperative complications (Modified Clavien-Dindo-Sink [M-CDS] Complication Classification) and time to return to sport (RTS). Descriptive statistics were performed, and univariate analyses were conducted to compare the outcomes of fixation groups. All analyses were performed in IBM SPSS v29.0.

Results:

Study criteria identified 15 patients with surgically treated AFITs during the study period who were predominantly male (93%) and had a mean age of 14.8±0.8 years. Injured patients most commonly participated in soccer (40%), with the most common mechanism being running or sprinting (40%). The avulsed fracture fragments were a mean of 41.5mm in size, with a maximal displacement of 20.7mm and predominantly Type 1 - Lateral (80%). Surgical constructs included 4 with screw, 5 with suture anchor, 5 with cortical button, and 1 combined (screw and suture anchor). Postoperative complications occurred in nine patients (60%), including seven Type 1, one Type 2, and one Type 3 M-CDS. Within M-CDS Type 1, continued neurologic symptoms occurred in 2 patients (13.3%). No statistically significant difference was found between fixation types among the studied outcome variables; however, refracture (2 cases [M-CDS Types 2 and 3]) was only observed with suture anchor or combined (screw and suture anchor) constructs.

Conclusions:

Findings from this retrospective case series of three surgical techniques bolsters the limited literature base regarding the surgical treatment of AFITs in adolescents. Consistent return to sport was achieved across all fixation types. Postoperative complications were not infrequent but were largely low in severity. While clear differences between constructs were not found, the available study sample limited robust analysis. Refracture occurred only with suture anchor or screw/suture anchor constructs.