Treatment of acetabular fractures is challenging, not only because of its complicated anatomy but also because of the lack of fitting plates. Personalized titanium alloy plates can be fabricated by selective laser melting (SLM) but the biocompatibility of these three-dimensional printing (3D-printed) plates remains unknown. Plates were manufactured by SLM and their cytocompatibility was assessed by observing the metabolism of L929 fibroblasts incubated with culture medium extracts using a CCK-8 assay and their morphology by light microscopy. Allergenicity was tested using a guinea pig maximization test. In addition, acute systemic toxicity of the 3D-printed plates was determined by injecting extracts from the implants into the tail veins of mice. Finally, the histocompatibility of the plates was investigated by implanting them into the dorsal muscles of rabbits. The in vitro results suggested that cytocompatibility of the 3D-printed plates was similar to that of conventional plates. The in vivo data also demonstrated histocompatibility that was comparable between the two manufacturing techniques. In conclusion, both in vivo and in vitro experiments suggested favorable biocompatibility of 3D-printed titanium alloy plates, indicating that it is a promising option for treatment of acetabular fractures.

This study aims to examine the clinical efficacy and surgical techniques of the lateral-rectus approach for treatment of acetabular factures in elderly patients. After appropriate exclusion, 65 elderly patients with an acetabular fracture who was treated through the lateral-rectus approach from January 2011 and October 2016 were selected retrospectively. By analyzing the medical records retrospectively, the patients’ characteristics, fracture type, mechanism of injury, comorbid conditions, ASA class, operative time, intra-operative blood loss, and post-operative complications were assessed. Clinical examination radiographs have been taken, align with the Matta evaluation system. Functional outcomes were evaluated using surveys including SF-36, Harris hip score, and modified Merle D’Aubigne-Postel. All 65 patients had undergone the single lateral-rectus approach successfully. Surgery duration was 101.23 min on average (45–210), and intra-operative bleeding was 798.46 ml on average (250–1800). According to the Matta radiological evaluation, the quality of reduction evaluated 1 week after surgery was rated as “anatomical” in 41 (63.1%) cases, “imperfect” in 12 (18.5%) cases, and “poor” in 12 (18.5%) cases. The modified Merle D’Aubigne-Postel score performed 18 months after surgery was categorized as excellent in 40 (61.5%) cases, good in 10 (15.4%) cases, and fair in 15 (23.1%) cases. The mean Harris Hip score was similar as present researches, being 87.18. The mean SF-36 score was 69.12 which was considered as normal for the group age 60 and older. Several complications were found, including screw loosening in 10 cases, fat liquefaction of incision in 2 cases, deep vein thrombosis in 2 cases, and temporary weakness of hip adductors in 5 cases. None of the patients had heterotopic ossification. The lateral-rectus approach is a valuable alternative to the ilioinguinal and modified Stoppa approach, being the treatment of acetabular fractures in elderly patients.

Background. Three-dimensional (3D) printing of an acetabular wing-plate is a new minimally invasive surgical technique for complex acetabular fractures. Objectives. To investigate the biomechanical stability of 3D printing acetabular wing-plates. The results were compared with 2 conventional fixation systems. Material and methods. Eighteen fresh frozen cadaveric pelvises with both column fractures were randomly divided to 3 groups: A - iliosciatic plates fixation system; B- 3D printing plates; C- 2 parallel reconstruction plates fixation system. These constructions were loaded onto a biomechanical testing machine. Longitudinal displacement and stiffness values of the constructs were measured to estimate their stability. Results. When the load force reached 700 N, Group A was superior to Group B in the longitudinal displacement of point 1 (p > 0.05). The longitudinal displacement of point 2 showed no significant differences among Groups A, B and C, and the displacement of the fracture line over point 3 showed no significant differences between Groups A and B (p > 0.05). The axial stiffness of Groups A, B and C were 122.4800 +/- 8.8480 N/mm, 168.4830 +/- 14.8091 N/mm and 83.1300 +/- 3.8091 N/mm, respectively. Group B was significantly stiffer than A and C (p < 0.05). Loads at failure of internal fixation were 1378.83 +/- 34.383 N, 1516.83 +/- 30.896 N and 1351.00 +/- 26.046 N for Groups A, B and C, respectively. Group B was significantly superior to Groups A and C (p > 0.05). Conclusions. Customized 3D printing acetabular-wing plates provide stability for acetabular fractures compared to intraspecific buttressing fixation.