Anterior Cruciate Ligament Reconstruction

BackgroundAppropriate graft tension and secure graft incorporation in bone tunnels are essential for successful anterior cruciate ligament (ACL) reconstruction using hamstrings tendon autografts. The WhipKnot™ soft tissue cinch, introduced by Smith and Nephew in 2004, is an alternative option to the commonly used whipstitch technique during preparation of the hamstring autograft in ACL reconstruction.AimsTo investigate the effectiveness of the WhipKnot™ soft tissue cinch and technique during the preparation of the tendon graft for ACL reconstruction.MethodA total of 33 ACL reconstruction operations performed between February 2011 and December 2011 were included in this study. These were performed by a single senior surgeon who used the Whipknot™ technique for the preparation of each graft. Four were used for each operation; two for each end of the harvested hamstrings tendons, including semitendinosus and gracilis tendons respectively.ResultsIn total, 132 WhipKnots were used during the knee operations. Use of the WhipKnot™ technique resulted in successful graft preparations, tensioning and effective graft placement in the tibial and femoral tunnels in almost all instances. Only one case of WhipKnot™ failure (slippage) was recorded.ConclusionThese results indicate that the Whipknot™ technique is a safe, reliable and practical option for the preparation of the hamstrings autografts

Metal ion levels post primary unilateral total knee arthroplasty

BackgroundMetal ion release from metal implants through the processes of mechanical wear and corrosion has been one of the main concerns post total joint arthroplasty. However, there have been very few studies to show metal ion exposure post total knee implants.AimsThe aim of this study was to investigate whether blood metal ion levels are raised in patients with well-functioning unilateral primary total knee arthroplasty in the short and the long term after surgery.Methods Whole blood Chromium and serum Cobalt levels were measured in 22 patients following primary total knee arthroplasty at a minimum of 12 months after surgery and then repeated at a mean of four years. Eleven patients had the cemented triathlon knee system and 11 patients had an uncemented ACS knee system with multilayer coatings.Results Cobalt levels in our study are low one year after TKR and stayed within normal limits with no significant rise at four years (p=0.300). Chromium levels raised significantly by four years (p=0.007), but remained within normal range with no evidence of toxic systemic effects. Our data showed no statistically significant difference for cobalt and chromium levels between ACS and Triathlon groups (p=0.62; p=0.54 respectively).ConclusionAt an average of 50-months post well-functioning total knee arthroplasty, whole blood Chromium levels and serum Cobalt levels are within the normal range. The use of cement is unlikely to influence metal ion release and titanium nitride coating did not influence metal ion release from TKR implants

Hamstrings tendon graft preparation for anterior cruciate ligament reconstruction using the WhipKnot™ soft tissue cinch technique

Appropriate graft tension and secure graft incorporation in bone tunnels are essential for successful anterior cruciate ligament (ACL) reconstruction using hamstrings tendon autografts. The WhipKnot™ soft tissue cinch, introduced by Smith and Nephew in 2004, is an alternative option to the commonly used whipstitch technique during preparation of the hamstring autograft in ACL reconstruction.To investigate the effectiveness of the WhipKnot™ soft tissue cinch and technique during the preparation of the tendon graft for ACL reconstruction.A total of 33 ACL reconstruction operations performed between February 2011 and December 2011 were included in this study. These were performed by a single senior surgeon who used the Whipknot™ technique for the preparation of each graft. Four were used for each operation; two for each end of the harvested hamstrings tendons, including semitendinosus and gracilis tendons respectively.In total, 132 WhipKnots were used during the knee operations. Use of the WhipKnot™ technique resulted in successful graft preparations, tensioning and effective graft placement in the tibial and femoral tunnels in almost all instances. Only one case of WhipKnot™ failure (slippage) was recorded.These results indicate that the Whipknot™ technique is a safe, reliable and practical option for the preparation of the hamstrings autografts

Metal ion levels post primary unilateral total knee arthroplasty

BackgroundMetal ion release from metal implants through the processes of mechanical wear and corrosion has been one of the main concerns post total joint arthroplasty. However, there have been very few studies to show metal ion exposure post total knee implants.AimsThe aim of this study was to investigate whether blood metal ion levels are raised in patients with well-functioning unilateral primary total knee arthroplasty in the short and the long term after surgery.MethodsWhole blood Chromium and serum Cobalt levels were measured in 22 patients following primary total knee arthroplasty at a minimum of 12 months after surgery and then repeated at a mean of four years. Eleven patients had the cemented triathlon knee system and 11 patients had an uncemented ACS knee system with multilayer coatings.ResultsCobalt levels in our study are low one year after TKR and stayed within normal limits with no significant rise at four years (p=0.300). Chromium levels raised significantly by four years (p=0.007), but remained within normal range with no evidence of toxic systemic effects. Our data showed no statistically significant difference for cobalt and chromium levels between ACS and Triathlon groups (p=0.62; p=0.54 respectively).ConclusionAt an average of 50-months post well-functioning total knee arthroplasty, whole blood Chromium levels and serum Cobalt levels are within the normal range. The use of cement is unlikely to influence metal ion release and titanium nitride coating did not influence metal ion release from TKR implants