Management of acute knee dislocations: anatomic repair and ligament bracing as a new treatment option-results of a multicentre study.

PURPOSE: The literature shows no consensus regarding the best method and timing for the treatment of acute knee dislocations. Studies indicate that a one-stage procedure performed in the early stages of injury can lead to superior results. The aim of this study was to evaluate the results after performing early surgical repair with additional suture augmentation (ligament bracing) of all torn ligaments in acute knee dislocations. METHODS: In this prospective multicentre study, 73 patients with an acute type III or IV knee dislocation were treated with one-stage ligament bracing within 10 days. Twenty-six patients sustained a type III medial dislocation, thirty-nine patients sustained a type III lateral dislocation, and eight patients presented a type IV dislocation. Four patients were lost to follow-up. Within the follow-up evaluation, various scores were collected (International Knee Documentation Committee IKDC Score, Tegner Score and Lysholm Score). Additional stress radiography was performed (Telos™) postoperatively. RESULTS: Sixty-nine knee dislocations (Schenck III and IV) with a follow-up at a mean of 14 ± 1.6 months were evaluated. The average IKDC score was 75.5 ± 14.5, the average Lysholm score was 81.0 ± 15.5, and the median loss of activity in the Tegner score was 1 (range 0-3) point. Stress radiographs showed side-to-side differences at a mean of 3.2 ± 1.3 mm for the anterior cruciate ligament (ACL) and of 2.9 ± 2.1 mm for the posterior cruciate ligament (PCL). The operative revision rate (early and late) was 17.4%. In the early stage, one wound infection and one case of transient common peroneal nerve (CPN) paresis were successfully revised. In the later stage, four patients with knee stiffness and six cases with symptomatic knee instability needed reoperation. Patients without ultra-low velocity (ULV) dislocations or CPN showed good or excellent results in 87.5% according to the Lysholm score. CONCLUSION: In cases of acute knee dislocation, primary ACL and PCL transosseous sutures with additional suture augmentation predominantly lead to good and excellent clinical results. Obese patients sustaining ultra-low velocity (ULV) dislocations and patients following injury to the CPN show inferior outcomes. In patients without ULV and CPN intraoperative and postoperative complications occurred in 10.1%. The obtained results and revision rates show that early primary suture repair is a promising option. LEVEL OF EVIDENCE: Prospective multicentre study, II.

Biomimetic modification of the TiO(2)/glass composite Ecopore with heparinized collagen and the osteoinductive factor BMP-2.

The porous TiO(2)/glass composite Ecopore has potential applications in hard tissue replacement. We describe the modification of Ecopore with the growth factor bone morphogenetic protein-2 (BMP-2) to add osteoinductive properties. Ecopore covalently coated with BMP-2 caused a weak induction of alkaline phosphatase in murine embryonal fibroblasts. In a rabbit bone defect model, BMP-2-coated Ecopore had moderately higher bone apposition rates and ingrown bone quantities at 6 weeks after implantation. To overcome loss of function due to chemical surface coupling, we filled the pore system of Ecopore with heparinized collagen sponge and loaded this secondary matrix with BMP-2. Heparinization of collagen filling increased the BMP-2 loading capacity of the matrix approximately 1.28-fold. Within 96 h, 17.0+/-0.1 and 10.1+/-0.2% of the used BMP-2 was released from non-modified and heparinized Ecopore/collagen, respectively, indicating that the heparin modification retarded BMP-2 release. Revealed by energy-dispersive X-ray spectroscopy analysis of implant cross-sectional areas, BMP-2-loaded Ecopore/collagen had significantly higher bony ingrowth quantities in rabbits, with the heparinized modification yielding the highest value (16.09+/-3.51%, p<0.005) compared with the non-heparinized matrix (10.72+/-4.07%, p<0.05) and the BMP-2-free controls (5.60+/-1.47%). This suggested a beneficial effect of the biomimetic modification of Ecopore with heparinized collagen for bone healing and integration.