Biomechanical Laboratory Article Example | Topics and Well Written Essays - 1000 words

Biomechanical Laboratory - Article Example Bioabsorbable interference screws are popular in endoscopic reconstructions of the ACL as there is no need for a second operation for removal and no complicating factor in case of a revision surgery. Pullout studies of metal and bioabsorbable interference screws have yielded similar results. However, a randomized controlled clinical trial comparing patients having metal interference screws with those having bioabsorbable poly-l-lactic acid screws showed subjective knee function to be better in the patients in the metal screw group although no difference in stability was noted between the two groups (Drogset et al., 2005) 3. Bioabsorbable interference screw breakage can be a problem in ACL reconstructive surgery which necessitates burying the screw on graft fixation (MacDonald and Arneja, 2003 ) 4. Partial or non-uniform degradation of bioabsorbable screws could lead to breakage with daily activities (Hall et al., 2009) 5. An in vitro study by Schwach and Vert (1999)6 showed a loss of 50% of compression strength in poly-L-lactic acid screws due to hydrolytic degradation between 2 and 5 months. While the overall complication rate associated with the use of this implant is low, complications involving osteolysis and aseptic effusion of the knee joint have been reported (Baums et al., 2006)7. Other complications that have been reported with bioabsorbable interference screws include cyst formation, tunnel widening, late screw breakage, and intra-articular migration (Appelt et al., 2007; Lembeck et al., 2005) 8, 9 According to Weiler et al. (1998)1, graft fixation close to the ACL insertion site increases anterior knee stability. The authors could do this successfully using a round threaded biodegradable interference screw. Interference screw fixation of bone-patellar tendon-bone grafts is a well-established process in ACL fixation. A study was conducted by Zheng.