Objective To compare the effect of mosaicplasty, mosaicplasty with gene enhanced tissue engineering and mosaicplasty with the gels of non-gene transduced BMSCs in alginate on the treatment of acute osteochondral defects. Methods Western blot test was conducted to detect the expression of hTGF-β1, Col II and Aggrecan in 3 groups, namely hTGF-β1 transduction group, Adv-βgal transduction group and blank control group without transduction. Eighteen 6-month-old Shanghai mascul ine goats weighing 22-25 kg were randomized into groups A, B and C (n=6). BMSCs were isolatedfrom the autologous bone marrow of groups B and C, and were subcultured to get the cells at passage 3. In group B, the BMSCs were transduced with hTGF-β1. For the animals of 3 groups, acute cyl indrical defects 5 mm in diameter and 3 mm in depth were created in the weight bearing area of the medial femoral condyle of hind l imbs. In group A, the autologous osteochondral mosaicplasty was performed to repair the defect; in group B, besides the mosaicplasty, the dead space between the cyl indrical grafts and the host cartilage were injected with the suspension of hTGF-β1 gene transduced autogenous BMSCs in sodium alginate, and CaCl2 was dropped into it to form calcium alginate gels; in group C, the method was the same as the group B, but the BMSCs were not transduced. General condition of the goats after operation was observed, the goats were killed 12 and 24 weeks after operation to receive gross and histology observation, which was evaluated by the histological grading scale of O’Driscoll, Keeley and Salter. Immunohistochemistry and TEM observation were performed 24 weeks after operation. Results Western blot test showed the expression of the hTGF-β1, Col II and the Aggrecan in the hTGF-β1 transduction group were significantly higher than that of the Adv-βgal transduction and the blank control groups. All the goats survived until the end of experiment and all the wounds healed by first intention. Gross observation revealed the boundaries of the reparative tissue in group B were indistinct, with smooth and continuous surfaces of the whole repaired area; while there were gaps in the cartilage spaces of groups A and C. Histology observation showed the dead space between the cyl indrical grafts in group A had fibrocartilage-l ike repair tissue, fill ing of fibrous tissue or overgrowth of the adjacent cartilage; the chondrocytes in group B had regular arrangements, with favorable integrations; while the dead space between the cyl indrical grafts in group C had fibrocartilage-l ike repair tissue, with the existence of gaps. The histology scores of group B at different time points were significantly higher than that of groups A and C, and group C was better than group A (P lt; 0.05); for group B, significant difference was detected between 12 weeks and 24 weeks in the histology score (P lt; 0.05）. Immunohistochemistry staining for Col II 24 weeks after operation showed the chondrocytes and lacuna of the reparative tissue in group B was obviously stained, while groups A and C presented l ight staining. TEM observation showed there were typical chondrocytes in the reparative tissue in group B, while parallel or interlaced arrangement collagen fiber existed in groups A and C. Conclusion Combining mosaicplasty with tissue engineering methods can solve theproblem caused by single use of mosaicplasty, including the poor concrescence of the remnant defect and poor integration with host cartilages.
【Abstract】 Objective To make the young patients with osteoarthritis and genu varum of knee delay total knee arthroplasty,to observe the cl inical effect of mosaicplasty of femoral medial condyle, patellar-plasty and high tibial osteotomy inthe treatment of osteoarthritis of knee with varum. Methods From June 2004 to February 2006, 8 patients with osteoarthritisof knee with varum(10 knees) were treated with combined operation such as mosaicplasty of femoral medial condyle, patellarplastyand high tibial osteotomy. There were 2 males with 3 knees, and 6 females with 7 knees,with an average age of 50 years(42-56 years). The left knees and right knees were involved in 3 cases respectively and bilateral knees in 2 cases. All patients hadknee ache after walk or long-time standing. The X-ray showed hyperosteogeny at peri-patella and circum ferential femur-tibialjoint，especially in the medial. The gap between patella and femur narrowed or disappeared，especially in the medial femurtibialjoint. The femoral tibial angel (FTA) was 185-200°(mean 190°). The HSS score of knee was 55-75(mean 60). The history ofknee ache was 1-12 years(mean 5 years). Results All patients were followed up for 7-24 months (mean 15 months). All theincisions healed by first intention, no early compl ication occurred. The cl inical bone heal ing time was 8-11 weeks(mean 9 weeks).Rectification of FTA was 15-30°(mean 20°). Normal weight-loading al ignment was recovered. The valgus angle of knee was 10°.The range of motion of knee was 100-120° after operation, increasing by 5-20° (mean 10°) when compared with preoperation.The X-ray of postoperation showed that genu varum was corrected obviously and that no displacement, loosening and breakageoccurred. The mean score of HSS was 80 (75-88), increasing by 20 when compared with preoperation. Conclusion Mosaicplastyof femoral medial condyle can make articular cartilage repair in certain degrees, patellar-plasty can rel ieve ache of fore region of knee effectively, and high tibial osteotomy can recover normal weight-loading al ignment. The curative effect is good withthe combined methods.
Objective To investigate the effectiveness of mosaicplasty in repair of large-sized osteochondral compound defects and the integrity of transplanted tissue with recipient sites so as to lay a foundation for clinical application. Methods Twenty-four adult goats were divided into 3 groups randomly. The diameters of defect were 6 mm for the medium-sized defects and 9 mm for the large-sized defects, which were created by a trepan. All of the defects were repaired with osteochondral plugs in diameters of 2 mm(the mediumsized defects) or 3 mm(the large-sized defects). The osteochondral plugs were harvested around the intercondylar fossa or intertrochlea groove, and pressed into the recipient sites by specialized instruments in a mosaic mode. No internal fixation was needed and the animal wereallowed to move freely after operation. From 4 to 24 weeks postoperatively, thespecimens were observed in gross and under electromicroscopy. X-ray detection and glycosaminoglycan(GAG) analysis were also performed to testify the healing processand the integrity of the cartilage and subchondral bone. Results The transplanted subchondral bone was integrated firmly with each other or with recipient sites in both mosaicplasty groups. But 24 weeks postoperatively, transplanted cartilage was not integrate with each other apparently. Obvious cleavage between cartilage plugs could be seen. But in the largesized defect groups, some of the osteochondral plugs were relapsed into the defects leaving the recipient sites some steps, leading to some degree of abrasion in the opposing articular cartilage. There was no significant difference in the GAG content between the transplanted cartilage and normal cartilage. X-ray analysis also demonstrated the healing process between the subchondral bone. Conclusion Mosaicplasty can repair the medium or small-sized osteochondral defects efficiently.