The positive impact of platelet-derived growth factor on the repair of full-thickness defects of articular cartilage.

OBJECTIVES: This study aims to investigate the potential use and histological effects of the local administration of platelet-derived growth factor (PDGF) in the repair of full-thickness osteochondral defects in articular cartilage in an animal model. MATERIALS AND METHODS: Twenty-four adolescent 18-week-old New Zealand White rabbits with an average weight of 2500 g (range, 1600 g to 3200 g) were used in the study. The rabbits were randomly divided into three groups (n=8) as the control group (group A) and two experimental groups (groups B and C). Defects of cylindrical full-thickness (3.5 mm wide, 4 mm deep) were created in the weight-bearing area of the right knee medial femoral condyles. In group A, the defect was left empty. In group B, the defect was filled with a collagen sponge. In group C, the defect was filled with a collagen sponge impregnated with PDGF. All rabbits were followed-up for 12 weeks. Right knee medial femoral condyles were used for macroscopic and histological analyses. RESULTS: At macroscopic level, the repair tissue was similar to normal adjacent cartilage at 12 weeks in group C. The surface of the repair tissue in group C was smoother and more regular compared to groups A and B. The total histological score of defects in group C was statistically significantly superior compared to groups A and B (p<0.05). Matrix staining and immunostaining of collagen type 2 were stronger in group C compared to the other groups, indicating the presence of a tissue similar to a normal cartilage. CONCLUSION: Platelet-derived growth factor can induce repair in full-thickness defects of articular cartilage in an animal model. Thus, this study demonstrates the potential use of PDGF for full-thickness osteochondral defects.

One-stage treatment of developmental dysplasia of the hip in untreated children from two to five years old. A comparative study.

A total of 38 children (49 hips) were retrospectively investigated to assess the efficacy and safety of one-stage treatment of developmental dysplasia of the hip (DDH) in untreated children from two to five years of age. Our method consisted of open reduction, Salter innominate osteotomy, femoral shortening and derotation osteotomy. The patients were distributed into two groups according to the age at which they were operated: Group I included 19 patients aged < 3 years (24 hips) and Group II included 19 patients aged > or = 3 years (25 hips). Mean follow-up was 5.08 years for Group I and 5.76 years for group II. Clinical and radiological assessment at final followup showed that the outcome was not significantly different between the two groups. Furthermore, after this follow-up period, the rates of avascular necrosis were similar. Children with DDH between two and five years of age were treated successfully with one-stage treatment.

Can rhBMP-2 containing collagen sponges enhance bone repair in ovariectomized rats?: a preliminary study.

With an aging population the frequency of postmenopausal fractures is increasing. Methods to enhance the repair of osteoporotic bone repair therefore become more important to reduce the society burden of care. We asked if absorbable collagen sponges containing recombinant human bone morphogenetic protein-2 (rhBMP-2) have the potential to enhance bone repair. We randomly assigned 40 rats into the ovariectomy and sham operation groups. A segmental defect was created in the right tibia 12 weeks after ovariectomy. rhBMP-2-containing absorbable collagen sponges were implanted into the defect in half of the animals in each group. We analyzed radiographs and histological sections and performed three-point bending tests to assess repair. Radiological scores in the rhBMP-2 applied rats were higher than those in controls at the end of 8 weeks after tibial osteotomy. The specimens failed under higher loads in the rhBMP-2-applied groups and histology revealed a higher fracture healing score, including callus formation, bone union, marrow changes, and cortex remodeling. We observed no adverse tissue responses such as fibrous connective tissue formation and inflammatory cellular infiltration. rhBMP-2 in absorbable collagen sponges enhanced bone repair in segmental tibial defects of ovariectomized rats. The sponges with rhBMP-2 appeared to enhance bone repair.

[The results of open surgical treatment in patients with chronic refractory lateral epicondylitis]. / Kronik, konservatif tedaviye dirençli lateral epikondilitte açik cerrahi tedavi sonuçlari.

OBJECTIVES: We evaluated the clinical and subjective functional results of open surgical treatment in patients with chronic refractory lateral epicondylitis. METHODS: Eleven patients (7 females, 4 males; mean age 42 years, range 29 to 56 years) underwent open surgical treatment for chronic refractory lateral epicondylitis. All the patients had received conservative treatment for at least a year without favorable response. Surgical procedure included release of the lateral extensor origin, excision of the degenerative tissue, decortication or drilling of the anterior lateral condyle, and repair of the extensor tendons. The results were evaluated according to the criteria proposed by Verhaar et al. The mean follow-up was 29 months (range 18 to 45 months). RESULTS: The results were excellent or good in 10 patients (90.9%) and acceptable in one patient (9.1%). The mean time to return to work was two months. Nine patients were free of pain in the forearm in the postoperative third month. No wound-related complications were encountered. On subjective evaluations, 10 patients reported full satisfaction, and one patient reported partial satisfaction with the result of the treatment. CONCLUSION: Open surgical procedure including release of the origins of the common extensor tendons and excision of the degenerative tissue yields favorable results in the treatment of patients with chronic refractory lateral epicondylitis.

[Soft tissue tendon graft fixation in the tibial tunnel with a bioabsorbable screw-EndoPearl combination in tibiae of low bone mineral density: a biomechanical study]. / Kemik mineral yogunlugu düsük tibialarda yumusak doku tendon greftinin emilebilir vida-EndoPearl kombinasyonuyla tibia tüneline tespiti: biyomekanik çalisma.

OBJECTIVES: This biomechanical study evaluated soft tissue tendon graft fixation in the tibial tunnel using a bioabsorbable interference screw with or without supplemental EndoPearl device. METHODS: Ten bovine tibiae were stripped of all soft tissues and bone tunnels 7 mm in diameter were drilled with dilation to 9 mm. Tibialis anterior allografts were fixed with a screw (10 mm in diameter, 30 mm in length) in five tibiae of high bone mineral density (1.36 g/cm2), and with a screw-EndoPearl combination in five tibiae of low bone mineral density (0.84 g/cm2). The specimens were cycled 10 times from 10 to 50 N, and 500 times from 50 to 200 N in a servo hydraulic test device prior to ultimate load-at-failure testing at a rate of 20 mm/min. RESULTS: No statistically significant differences were found between the two fixation groups with respect to displacement and stiffness during cyclic testing, and with respect to load at failure, displacement, and stiffness during load-to-failure testing (p>0.05). CONCLUSION: The finding of similar results in both fixation groups with respect to displacement and stiffness during cyclic testing and during load-to-failure testing suggests that a screw-EndoPearl combination in tibiae of low bone mineral density may be helpful in the prevention of graft slippage.