Complications of Anterior Subcutaneous Internal Fixation for Unstable Pelvis Fractures: A Multicenter Study

Background Stabilization after a pelvic fracture can be accomplished with an anterior external fixator. These devices are uncomfortable for patients and are at risk for infection and loosening, especially in obese patients. As an alternative, we recently developed an anterior subcutaneous pelvic internal fixation technique (ASPIF). Questions/purposes We asked if the ASPIF (1) allows for definitive anterior pelvic stabilization of unstable pelvic injuries; (2) is well tolerated by patients for mobility and comfort; and (3) has an acceptable complication rate. Methods We retrospectively reviewed 91 patients who incurred an unstable pelvic injury treated with an anterior internal fixator and posterior fixation at four Level I trauma centers. We assessed (1) healing by callous formation on radiographs and the ability to weightbear comfortably; (2) patient function by their ability to sit, stand, lie on their sides, and how well they tolerated the implants; and (3) complications during the observation period. The minimum followup was 6 months (mean, 15 months; range, 6-40 months). Results All 91 patients were able to sit, stand, and lie on their sides. Injuries healed without loss of reduction in 89 of 91 patients. Complications included six early revisions resulting from technical error and three infections. Irritation of the lateral femoral cutaneous nerve was reported in 27 of 91 patients and resolved in all but one. Heterotopic ossification around the implants, which was asymptomatic in all cases, occurred in 32 of 91 patients. Conclusions The anterior internal fixator provided high rates of union for the anterior injury in unstable pelvic fractures. Patients were able to sit, stand and ambulate without difficulty. Infections and aseptic loosening were reduced but heterotopic ossification and irritation of the LFCN are common. Level of Evidence Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.