Symptomatic chondral or osteochondral defects of the talus reduce the quality of life of many patients.Although their pathomechanism is well understood,it is well known that different aetiologic factors play a role in...Symptomatic chondral or osteochondral defects of the talus reduce the quality of life of many patients.Although their pathomechanism is well understood,it is well known that different aetiologic factors play a role in their origin.Additionally,it is well recognised that the talar articular cartilage strongly differs from that in the knee.Despite this fact,many recommendations for the management of talar cartilage defects are based on approaches that were developed for the knee.Conservative treatment seems to work best in paediatric and adolescent patients with osteochondritis dissecans.However,depending on the size of the lesions,surgical approaches are necessary to treat many of these defects.Bone marrow stimulation techniques may achieve good results in small lesions.Large lesions may be treated by open procedures such as osteochondral autograft transfer or allograft transplantation.Autologous chondrocyte transplantation,as a restorative procedure,is well investigated in the knee and has been applied in the talus with increasing popularity and promising results but the evidence to date is poor.The goals of the current article are to summarise the different options for treating chondral and osteochondral defects of the talus and review the available literature.展开更多
Interbody disc spacers for anterior spine fusion are made of different materials, such as titanium alloys or carbon fiber reinforced polymers (CFRP). Implant-related susceptibility artifacts can decrease the quality o...Interbody disc spacers for anterior spine fusion are made of different materials, such as titanium alloys or carbon fiber reinforced polymers (CFRP). Implant-related susceptibility artifacts can decrease the quality of MRI scans. This cadaveric study aimed to demonstrate the extent that implant-related MRI artifacting affects the post fusion differentiation of the spinal canal (SC) and intervertebral disc space (IDS). In 6 cadaveric porcine spines, we evaluated the post-im- plantation MRI scans of a titanium and CFRP spacer that differed in shape and surface qualities. A spacer made of human cortical bone was used as a control. A defined evaluation unit was divided into regions of interest (ROI) to characterize the SC and IDS. Considering 15 different MRI sequences read independently by an interobserver-validated team of specialists artifact-affected image quality of the median MRI slice was rated on a modified score of 0-1-2-3. A maximum score of 15 points for the SC and 9 points for the IDS (100%) was possible. Turbo spin echo sequences produced the best scores for both spacers and the control. Only the control achieved a score of 100%. For the IDS the titanium and CFRP spacer maximally scored 0% and 74%, for the SC 80% and 99%, respectively. By using favored T1 TSE sequences the CFRP-spacer represented clear advantages in post fusion spinal imaging. Independent of artifact dimensions the used scoring system allowed us to create an implant-related ranking of MRI scan quality in reference to the bone control.展开更多
文摘Symptomatic chondral or osteochondral defects of the talus reduce the quality of life of many patients.Although their pathomechanism is well understood,it is well known that different aetiologic factors play a role in their origin.Additionally,it is well recognised that the talar articular cartilage strongly differs from that in the knee.Despite this fact,many recommendations for the management of talar cartilage defects are based on approaches that were developed for the knee.Conservative treatment seems to work best in paediatric and adolescent patients with osteochondritis dissecans.However,depending on the size of the lesions,surgical approaches are necessary to treat many of these defects.Bone marrow stimulation techniques may achieve good results in small lesions.Large lesions may be treated by open procedures such as osteochondral autograft transfer or allograft transplantation.Autologous chondrocyte transplantation,as a restorative procedure,is well investigated in the knee and has been applied in the talus with increasing popularity and promising results but the evidence to date is poor.The goals of the current article are to summarise the different options for treating chondral and osteochondral defects of the talus and review the available literature.
文摘Interbody disc spacers for anterior spine fusion are made of different materials, such as titanium alloys or carbon fiber reinforced polymers (CFRP). Implant-related susceptibility artifacts can decrease the quality of MRI scans. This cadaveric study aimed to demonstrate the extent that implant-related MRI artifacting affects the post fusion differentiation of the spinal canal (SC) and intervertebral disc space (IDS). In 6 cadaveric porcine spines, we evaluated the post-im- plantation MRI scans of a titanium and CFRP spacer that differed in shape and surface qualities. A spacer made of human cortical bone was used as a control. A defined evaluation unit was divided into regions of interest (ROI) to characterize the SC and IDS. Considering 15 different MRI sequences read independently by an interobserver-validated team of specialists artifact-affected image quality of the median MRI slice was rated on a modified score of 0-1-2-3. A maximum score of 15 points for the SC and 9 points for the IDS (100%) was possible. Turbo spin echo sequences produced the best scores for both spacers and the control. Only the control achieved a score of 100%. For the IDS the titanium and CFRP spacer maximally scored 0% and 74%, for the SC 80% and 99%, respectively. By using favored T1 TSE sequences the CFRP-spacer represented clear advantages in post fusion spinal imaging. Independent of artifact dimensions the used scoring system allowed us to create an implant-related ranking of MRI scan quality in reference to the bone control.
