Bone tunnel positions in anterior cruciate ligament reconstruction evaluated by three-dimensional CT reconstruction based on Mimics software:modified transtibial versus anteromedial portal technique / 中国骨伤

OBJECTIVE@#To compare the femoral and tibial tunnel positions of anterior cruciate ligament reconstruction using the modified transtibial (MTT) technique and anteromedial (AM) portal technique.@*METHODS@#Between January 2017 and September 2020, 78 patients with anterior cruciate ligament rupture underwent single-bundle reconstruction with the modified transtibial technique in 39 cases (group MTT) and through anteromedial approach in 39 cases (group AM). There were 25 males and 14 females in group MTT, with an average age of (37.0±2.3) years old; 27 males and 12 females in group AM, with an average age of (37.5±2.2) years old. CT scan of the affected knee was conducted one week after the surgery to measure and compare the femoral tunnels positioning (Fx, Fy), tibial tunnels positioning in the frontal plane(Tx1), tibial tunnels positioning in the sagittal plane (Ty1), and tibial tunnels positioning in the axial plane (Tx2, Ty2) in patients undergoing anterior cruciate ligament reconstruction through Mimics software.@*RESULTS@#Three-dimensional CT reconstruction after the surgery showed that the average Fx and Fy were(25.2±2.1)% and (34.9±3.0)% respectively and the Tx1 and Ty1 were (45.5±3.3)% and (44.7± 3.0)% respectively, while the Tx2 and Ty2 were (47.0±3.0)% and (39.9±4.2)% respectively in group MTT. In group AM, the average Fx and Fy were (26.0±2.0)% and (36.1±3.9)% respectively and the Tx1 and Ty1 were (46.5±3.1)% and (45.6± 3.1)% respectively, while the Tx2 and Ty2 were (47.4±2.5)% and (39.6±3.9)% respectively. There were no statistically significant differences in the femoral and tibial tunnels between the two groups (@*CONCLUSION@#Both the MTT and AM technique can achieve good anatomical positioning of the femoral and tibial tunnels, without significant differences in the positioning of the bone tunnels.

A comparative study on two culture methods for adipose-derived stem cells from mice with osteoporosis / 中国组织工程研究

BACKGROUND:To obtain enough adipose-derived stem cells (ADSCs) is the premise of repairing osteoporotic bone defects by autograft transplantation;therefore,how to efficiently,simply and economically harvest primary autologous ADSCs is the key to the treatment of osteoporosis.OBJECTIVE:To isolate and culture ADSCs from mice with osteoporosis (OP-ADSCs) in vitro by tissue explant culture and collagenase digestion,and to compare the efficacies of these two methods.METHODS:Adipose tissues were isolated from the inguen of C57BL/6 mice,from which OP-ADSCs were obtained by tissue explant culture and collagenase digestion respectively.Then,the cells were subjected to primary culture and subculture.The surface specific antigens of passage 3 cells were observed using flow cytometry,while the yields and proliferation abilities of passage 3 were compared at 7 days of culture.The adipogenic and osteogenic differentiation of OP-ADSCs at passage 4 was detected.RESULTS AND CONCLUSION:(1) The expression levels of CD34,CD146,Sca-1 in passage 3 cells were (15.22±1.85)％,(75.55±3.36)％ and (83.48±4.22)％ for the tissue explant culture and (13.46±2.21)％,(76.62±2.47)％ and (84.84±3.56)％ for the collagenase digestion method,respectively.(2) The cell yield from each milligram of adipose tissue by tissue explant culture was significantly higher than that by collagenase digestion (P ＜ 0.05).(3) The proliferation rate of cells in the tissue explant culture group was higher than that in the collagenase digestion group after 24 hours of culture.(4) The OP-ADSCs cultured by the two methods could differentiate into adipocytes and osteoblasts,and the lipid accumulation and the mineralized nodules showed no significant difference between the two groups (both P＞ 0.05).These experimental findings indicate that the tissue explant culture is more suitable for obtaining OP-ADSCs in vitro as compared with collagenase digestion,which contributes to provide adequate cell sources for studies on ADSCs treatment of osteoporotic fractures and bone defects.

Surgical treatment for posterior Pilon fracture through posterolateral approach / 中国骨伤

<p><b>OBJECTIVE</b>To explore clinical results of open reduction and internal fixation (ORIF) for posterior Pilon fracture through posterolateral approach.</p><p><b>METHODS</b>Seventeen patients with posterior Pilon fracture were treated through posterolateral approach from February 2010 to April 2013. Among them,including 11 males and 6 females aged from 29 to 59 with an average of 43.4 years old. All fractures were associated with more than 20% of articular surface of distal tibial. The causes of injury included falling down (11 cases), traffic accident (4 cases) and sports injury(6 cases). Fracture classification was based on posterior pilon fracture by YU Guang-rong, including type I (6 cases), type II (2 cases) and type III (6 cases). Fracture healing time, fracture reduction and postoperative complications were observed, AOFAS score were applied to evaluate clinical efficacy.</p><p><b>RESULTS</b>All patients were followed up from 13 to 24 months with an average of 20.5 months. All incisions were healed at stage I, and fractures obtained healing,the time of fracture healing ranged from 12 to 21 weeks with an average of 15.2 weeks. No incision infection, neurovascular injury, bone ununion and fracture deformity were found after operation. Postoperative AOFAS score was 92.0 ± 10.2, and 14 cases got excellent results, 2 good and 1 moderate.</p><p><b>CONCLUSION</b>Posterior pilon fracture through posterolateral approach could obtain effective reduction, stable fixation. It is a safe, simple and effective operation for treating posterior Pilon fracture, and it is worth popularizing.</p>