Clinical Outcomes of the Central Third Patellar Tendon Versus Four-strand Hamstring Tendon Autograft Used for Anterior Cruciate Ligament Reconstruction: A Systematic Review and Subgroup Meta-analysis of Randomized Controlled Trials.

BACKGROUND: The most frequently used auto-grafts for ACL reconstruction (ACLR) are bone-patellar tendon-bone (BPTB) and four-strand hamstring tendon (4S-HT), but significant controversy exists about which graft is better. This study aimed to compare the knee outcomes following ACLR with BPTB and 4S-HT autografts. METHODS: Subgroup meta-analyses were performed basing on available randomised controlled trials (RCTs) according to different follow-up intervals. 23 RCTs were eligible for inclusion, involving 933 participants in each treatment group. RESULTS: Only short-term (≤2 years) knee anteroposterior and rotational stability were significantly poorer with 4S-HT when compared to BPTB autograft, as judged by side-to-side difference on knee laxity (WMD=-0.50, 95%CI -0.81~-0.18, p=0.002) and pivot-shift test (OR=0.58, 95%CI 0.39~0.88, p=0.010), respectively. The IKDC objective grade was evident to be in favour of 4S-HT group in mid-term (3-5 years) follow-up (OR=0.63, 95%CI 0.43~0.92, p=0.017). Several donor-site related complications, including anterior knee pain, pain with kneeling and extension deficit, were more frequent in BPTB autograft group, while lower short-term iskinetic peak flexion torques both at 60°/S (WMD=8.93, 95%CI 7.88~9.99, p<0.001) and 240°/S (WMD=11.63, 95%CI 9.92~13.34, p<0.001) were caused by HT harvesting. CONCLUSION: BPTB was associated with inferior mid- to long-term (>5 years) knee functional outcomes, and increased frequency of donor-site complications. In contrast, only short-term knee laxity was increased for 4S-HT autograft, which is expected to be improved by providing more conservative rehabilitation protocol and aperture fixation methods.

Outcomes of Intercalary Prosthetic Reconstruction for Pathological Diaphyseal Femoral Fractures Secondary to Metastatic Tumors.

OBJECTIVE: To evaluate the clinical outcomes and complications of segmental prosthetic reconstruction for pathological diaphyseal femoral fractures secondary to metastatic tumors. METHODS: Between 2011 and 2015, we retrospectively evaluated 16 patients (6 men and 10 women; 64.5 ± 11.4 years old at diagnosis) who underwent prosthetic reconstruction after segmental resection of diaphyseal femoral fractures due to metastatic lesions. Visual analog scale (VAS), functional outcomes, implant-related complications, and Mean postoperative Musculoskeletal Tumor Society (MSTS) score for each patient were collected. RESULTS: The mean length of bone defect was 10.2 ± 2.6 cm (range, 8-16 cm); follow-up was 9 ± 6.8 months (range, 2-25 months) for all patients, and 24 months (23 and 25 months) for the 2 patients still alive. At final follow-up, 14 patients were dead, indicating a mean survival of 6.9 ± 3.6 months (range, 2-14 months). Mean preoperative VAS score was 8.5 ± 1.0, which decreased to 2.5 ± 1.3 at day 2 postoperatively, indicating significant pain relief (P < 0.05). The MSTS score for lower extremities was 84.6% (range, 73%-90%). The range of motion and function of adjacent joints was within the normal limits in all cases. Three patients (33%) developed complications, including aseptic loosening because of disease progression (1), infection (1), and peri-prosthesis fracture (1). CONCLUSION: These findings demonstrated that this approach greatly relieves pain, and yields satisfactory functional outcomes with fewer complications in patients with pathological femoral fractures secondary to metastatic tumors; however, survival was not significantly improved.

Management of great vessels and nerves in limb-salvage surgery for bone and soft tissue tumors.

In recent years, limb-salvage surgery has gradually replaced amputations and become one of the main treatment strategies for patients with bone and soft tissue tumors of the extremities. The goals of tumor resection in limb-salvage surgery are to reduce the recurrence rate and preserve as much limb function as possible. However, depending on the size and specific location of the tumor, large neurovascular bundles may be involved. In addition, management of large nerves and vessels can make wide marginal resection more difficult. Sites where these problems commonly arise include the sciatic and tibial common peroneal nerve, artery and vein in the lower limbs.

Tissue-engineered calcium phosphate cement in rabbit femoral condylar bone defects.

BACKGROUND: Calcium phosphate cement (CPC) is a favorable bone-graft substitute, with excellent biocompatibility and osteoconductivity. However, its reduced osteoinductive ability may limit the utility of CPC. To increase its osteoinductive potential, this study aimed to prepare tissue-engineered CPC and evaluate its use in the repair of bone defects. The fate of transplanted seed cells in vivo was observed at the same time. METHODS: Tissue-engineered CPC was prepared by seeding CPC with encapsulated bone mesenchymal stem cells (BMSCs) expressing recombinant human bone morphogenetic protein-2 (rhBMP-2) and green fluorescent protein (GFP). Tissue-engineered CPC and pure CPC were implanted into rabbit femoral condyle bone defects respectively. Twelve weeks later, radiographs, morphological observations, histomorphometrical evaluations, and in vivo tracing were performed. RESULTS: The radiographs revealed better absorption and faster new bone formation for tissue-engineered CPC than pure CPC. Morphological and histomorphometrical evaluations indicated that tissue-engineered CPC separated into numerous small blocks, with active absorption and reconstruction noted, whereas the residual CPC area was larger in the group treated with pure CPC. In the tissue-engineered CPC group, in vivo tracing revealed numerous cells expressing both GFP and rhBMP-2 that were distributed in the medullar cavity and on the surface of bony trabeculae. CONCLUSION: Tissue-engineered CPC can effectively repair bone defects, with allogenic seeded cells able to grow and differentiate in vivo after transplantation.