ОбзОры т р а в м а т О л О г и я и О р т О п е д и я р О с с и и 2015-2 (76)

Aim – to evaluate in the experimental study in vitro the duration of antimicrobial activity of fosfomycin-impregnated bone cement and to study the dynamics of radiological and morphological changes depending on the local antibiotic therapy in two-stage treatment of chronic osteomyelitis in rabbits.Materials and methods. Duration of antimicrobial activity of bone cement (depuy cmw1 gentamicin) with fosfomycin in vitro was studied in comparison to cements with vancomycin and controls without additional antibiotics. Presence of the lysis zone of bacterial cultures was evaluated (Staphylococcus aureus ATCC6538 and ATCC33591, Klebsiella pneumoniae ATCC33495 and Escherichia coli ATCC25922) after application of 10 μl of the solution, collected from the cement samples after incubation for 24 hours. For the in vivo experiment, Chinchilla rabbits (n = 20) with local osteomyelitis of the tibia underwent two-stage treatment where substitution of the bone defect at stage I was performed with PMMA and stage II – with the bioresorbable material based on hydroxyapatite and triclacium phosphate (ReproBone). In an experience group (n = 10) before setting osteoreplacement materials with fosfomycin (group FOSFO), and by control (n = 10) – vancomycin (group VANCO). X-ray imaging was performed on the 1st and 21st day after installation of the cement spacer, and 45th day after substitution of the spacer with the bioresorbable material. Microbiological analysis of the samples was performed intraoperatively and on the 7th, 14th day after each stage. Histological study was conducted in both groups on the 14th, 21th day after stage I and 45th day after stage II of the treatment.Results. Maximal duration of antimicrobial activity in vitro was observed in samples of PMMA with fosfomycin whereas minimal – in control samples of gentamicin-based bone cement. Relief of the infection was attained in all animals while application of fosfomycin resulted in a more rapid elimination of the bacteria. Reaction of the adjacent tissue to the implanted material and results of X-ray imaging in both groups did not differ significantly. Long duration of the broad-spectrum antimicrobial activity of the bone cement with fosfomycin with the comparable perifocal reaction in vivo necessitates further study of the use of this antibiotic in bioresorbable materials for the treatment of osteomyelitis in clinical practice.

Surgical treatment results for 13 patients with local deep defects of the articular surface of femoral condyle are presented. Surgical treatment was performed in two steps. At first step diagnostic arthroscopy with removal of loose intraarticular bodies, resection of injured menisci and harvesting of fat body tissues for multipotent mesenchymal stromal cells (MMSC) isolation were applied. Second step consisted of knee arthroplasty; zone of defect was covered with collagen membrane Chondro-Gide under which MMSC were implanted. Control arthroscopy with biopsy of articular surface fragment in the zone of defect restoration was performed to four patients (30.8%) 2 years after arthroplasty. It is shown that after surgical intervention cartilage regeneration goes on owing to fibrillar cartilage formation. In 2 years follow up good results were achieved in 92.3% of cases that proved the efficacy of the elaborated technique for restoration of knee joint function and slowing down of degenerative-dystrophic changes development

Purpose of the study – search for morphological cause of failure for free tendon auto and allografts after ACL reconstruction of the knee joint in early postoperative period during in vivo experiment. Materials and methods. Experiment included two groups of rabbits, each group consisting of 9 animals. In the first group the authors performed ACL autografting by semitendinous tendon harvested from operated limb. In the second group, ACL allografting was made by foot flexor tendon harvested earlier in rabbits excluded from present or other experiments after pretreatment and sterilization in modified Belyakov’s medium. Results. The major cause for failure of ACL tendon grafts after reconstruction in early postoperative period is the necrosis of intraarticular portion of auto or allograft on the 15th day after the procedure. In case of overexposure of the graft in early period the authors observed rupture along intraarticular portion or - more probable - along the demarcation area (serrated line) rather than graft slipping from bone tunnel with slackening. Intra-tunnel graft portion during first several days after the procedure became surrounded by granulated tissue in contrast to intraarticular portion that remained bare of such support. Conclusion. Comparative experimental and morphological study of two options of ACL reconstruction demonstrated a uniformity of alterations in dynamics with a certain delay in development of compensatory and adaptive processes after allografting. Necrosis (or homogenization) of intraarticular portion of auto or allograft is the cause for potential failure of ACL reconstruction in case of an extremely early and unjustified active rehabilitation.

Surgical treatment results for 13 patients with local deep defects of the articular surface of femoral condyle are presented. Surgical treatment was performed in two steps. At first step diagnostic arthroscopy with removal of loose intraarticular bodies, resection of injured menisci and harvesting of fat body tissues for multipotent mesenchymal stromal cells (MMSC) isolation were applied. Second step consisted of knee arthroplasty; zone of defect was covered with collagen membrane Chondro-Gide under which MMSC were implanted. Control arthroscopy with biopsy of articular surface fragment in the zone of defect restoration was performed to four patients (30.8%) 2 years after arthroplasty. It is shown that after surgical intervention cartilage regeneration goes on owing to fibrillar cartilage formation. In 2 years follow up good results were achieved in 92.3% of cases that proved the efficacy of the elaborated technique for restoration of knee joint function and slowing down of degenerative-dystrophic changes development