The Outcomes of Conservative Versus Surgical Treatment of Pelvic and Hip Avulsion Fractures: A Systematic Review and Meta-Analysis

BACKGROUND: Avulsion fractures of the pelvis and hip are common injuries in adolescent patients. Avulsion sites include the rectus femoris at the anterior inferior iliac spine (AIIS), the sartorius at the anterior superior iliac spine (ASIS), the hamstrings at the ischial tuberosity, abdominal muscles on the iliac crest (IC), iliopsoas at the lesser trochanter (LT). Although these fractures are commonly treated conservatively, there is no consensus on the preferred treatment modality (conservative vs. surgical fixation) or thresholds for surgical treatment. The published literature is generally limited to small retrospective series, with in some cases conflicting results. PURPOSE: To summarize the available evidence on outcomes of pelvic and hip avulsion fractures in the pediatric and adolescent population using a systematic review of the literature. STUDY DESIGN: Systematic review. METHODS: A systematic review of the literature was performed per PRISMA guidelines. Inclusion criteria included mean patient age of ≤18.0 years, ≥5 patients, avulsions treated with 3 months of injury, and publication in the English language. Patient characteristics, type of activity performed when injured, treatment modality, complications, and outcomes (rates of persistent symptoms, return to sport, subsequent surgery), were recorded by specific fracture type. RESULTS: A total of 1034 patients with acute avulsion fractures from 23 studies were included. Of these, the outcomes were reported in 799 patients, including 693 (86.7%) who underwent conservative treatment and 106 (13.3%) who underwent surgical intervention. All types of acute avulsion fractures had good results with conservative treatment. Ischial tuberosity avulsions had the highest rate of persistent symptoms (25.4%) but only 10.2% underwent subsequent surgery. AIIS avulsions also had a high rate of persistent symptoms (19.3%) but very few underwent subsequent surgery (1.3%). Faster return to sport was noted in conservatively treated patients in ASIS and AIIS avulsions (both p<0.05). While good results have been reported with surgical treatment, conservative treatment of ASIS, AIIS, ischial tuberosity, IC, and LT avulsions appears to be nearly uniformly successful with low rates of persistent symptoms or subsequent surgery. CONCLUSIONS: Both conservative treatment and surgical treatment of pelvic avulsion injuries appear to be effective for the majority of patients. Ischial tuberosity and AIIS avulsions have the highest rates of persistent symptoms at 25% and 19%, respectively. Further prospective research into all fracture types is needed to better define indications for surgery in a subgroup of patients.