Midterm radiologic and functional outcomes of minimally-invasive fixation of unstable pelvic fractures using anterior internal fixator(INFIX) and percutaneous iliosacral screws.

BACKGROUND: Anterior pelvic external fixation is associated with pin site infections, aseptic loosening with loss of reduction, frame bulkiness hindering patient mobilization and consequent difficulties in inpatient nursing. We performed a single-center prospective series to evaluate the feasibility, safety, limitations and midterm radiologic and functional outcomes of an alternative minimally invasive pelvic internal fixation technique using an anterior subcutaneous pelvic internal fixator (INFIX) and percutaneous iliosacral screws in unstable pelvic ring fractures.
METHODS: Fifteen consecutive patients with vertically and/or rotationally unstable pelvic fractures, presenting to a Level-1 trauma center were treated with closed reduction, appropriate posterior stabilization with percutaneous iliosacral screws and anterior INFIX application. Outcomes were analyzed with respect to the quality of fracture reduction (Matta's radiologic criteria), ease of inpatient nursing, patient mobility and comfort, functional outcomes at final follow-up (Majeed score, SF-12 score), social reintegration and complications.
RESULTS: Most common injury pattern was AO/OTA type 61-C pelvic fracture in thirteen patients. Mean procedure time and intra-operative blood loss were, 57.1+/-4.9 min (range,51-68 min) and 115.3+/-26.7 ml (range,80-170 ml) respectively. Mean follow-up was 34.9+/-4.1 months (range,31-42 months). Fracture reduction was excellent in twelve and good in three patients (Matta's criteria). Functional outcomes were excellent in eight and good in seven patients (Majeed score). Mean SF-12 scores for physical and mental health were 48.58+/-5.61 and 50.89+/-3.97 respectively. Thirteen patients returned to their pre-injury jobs. All fifteen patients reintegrated into society without any restrictions. INFIX was removed at a mean post-operative period of 7.3+/-1.5 months (range,5.5-11 months). Complications included, lateral femoral cutaneous nerve irritation(n = 1), superficial wound infection(n = 1) and loss of reduction(n = 2).
CONCLUSION: Minimally invasive pelvic stabilization using INFIX and percutaneous iliosacral screws is easy to learn and apply, achieves good fracture reduction and definitive stabilization with minimum complications and offers excellent functional outcomes at a minimum follow-up of 31 months. LEVEL OF EVIDENCE: Level IV.