RESUMO
Objective To investigate the curative effect of arthroscopic treatment for lateral dis-cord meniscus tear in children. Methods The study involved 229 child patients with lateral discord meniscal tear treated arthroscopically from March 1996 to March 2008. There were 133 males and 96 fe-males, at age of (9±3.5) years (range 4-14 years). The treatment methods included meniscus-plasty in 219 patients (including two children with postoperative recurrence), meniscus-plasty-suture in eight and partial meniscectomy in two. The function of the knees was assessed pre-operationally and post-operation-ally by using Lysholm score. Results Of all, 221 patients were followed up for a period of (65±48.9) months (range 5-144 months). The pain and swelling were alleviated, with obvious improvement in range of motion and knee function in all patients six months after operation. There were no complica-tions including intra-articular infection, iatrogenic injury, fibroarthritis or loss of range of motion. Ly-sholm score was (61.85±7.65) points (range 45-73) before operation, which was improved to (95.30±3.50) points (range 87-100 points) six months after operation (t= 26.778, P < 0.01). Conclusion Treatment of lateral discord meniscus tear under arthroscopic guidance in children has the advantages of minor trauma, satisfactory results, can maintain good shape of the meniscus and good func-tion of knee and reduce incidence rate of osteoarthritis.
RESUMO
This study was designed to assess the effect of implantation site and environment on early in vivo degradation behaviors of poly(L-lactide) (PLLA) and poly(L-lactide-co-glycolide) (PLGA) copolymer. The rods were implanted at two sites in each of 24 New Zealand White rabbits. The first site was within the suprapatellar bursa of the joint cavities (JC) and the second site was in the opposite condyles of femurs (CF). Three rabbits of each group underwent explantation of rods after 4, 8, 12, and 16 weeks. At each interval, measures were taken to evaluate the molecular weight, shear strength, weight loss and thermal properties of PLLA and PLGA. It was found that PLGA degraded slightly faster than PLLA. After 16 weeks, PLLA's initial inherent viscosity of 4.6 decreased to about 3.4 in both implantation sites while that of PLGA decreased from 4.6 to about 2.2. Both PLGA and PLLA showed enough shear strength retention in 16 weeks (> or = 53MPa) within 16 weeks. Autocatalysis mechanism was confirmed by the fact of accelerated weight loss of PLGA after 8 weeks and of PLLA after 12 weeks. The results revealed that PLGA could be a promising candidate material as a replacement of PLLA in internal fixation of bone fractures, and no significant difference of early in vivo degradation behaviors between PLLA and PLGA was observed in regard to different implantation sites in 16 weeks.