We measured the intercondylar notch of the femur in female handball players from radiographs of 20 players with previous unilateral anterior cruciate ligament injury, and 26 controls without injury. The groups were comparable regarding age, height, weight and level of performance. Intercondylar fossa radiographs were obtained in a posteroanterior axial position. The anterior opening of the intercondylar notch was narrower in the healthy knee of the injured group compared to the controls. There was an increased risk of anterior cruciate ligament injury associated with decreasing notch opening: female handball players with 17 mm or less anterior notch width were 6 times more susceptible to anterior cruciate ligament injury compared to players with wider notch width.
The present study was undertaken to examine how osteoarthritis affects the expression of type-X collagen, a hypertrophic chondrocyte-specific collagen in articular cartilage. A well characterized sheep polyclonal antiserum, as well as three mouse monoclonal antibodies against canine type-X collagen, was used to immunolocalize type-X collagen in human and canine joints. Its expression in osteoarthritic cartilage was altered in several locations. In the canine osteoarthritic joints, type-X collagen increased in and just above the zone of calcified cartilage and was present diffusely throughout the calcified matrix. In both the human and canine cartilage, type-X collagen was localized around cell clones in the transitional zone of cartilage. This is surprising, since that region of the cartilage does not calcify and one of the proposed roles of type-X collagen is in mineralization. Thus, the osteoarthritic process may damage the matrix in the superficial layer and induce changes leading to the expression of the hypertrophic chondrocyte phenotype.
Type X collagen was extracted from ends of canine growth plates by pepsin digestion after 4 M guanidine hydrochloride extraction, purified by stepwise salt precipitation (2.0 M NaCl in 0.5 M acetic acid), and chromatographed on a Bio-Gel A1.5 M column in 1.0 M CaCl2. Without reduction on sodium dodecyl sulfate (SDS) polyacrylamide gels, the preparation yielded a single, high-molecular-weight (mol wt) band; after reduction, a single band of relative mol wt 5.0 x 10(4) was found. Polyclonal sera were raised against the purified collagen and used in the immunolocalization of canine type X collagen. As expected, indirect immunoperoxidase (IP) or indirect immunofluorescent staining with the polyclonal sera demonstrated that most of the immunoreactivity was localized in the zone of provisional calcification of the growth plate and in cartilage remnants in the metaphyseal region of the physis. A progressive decrease in staining toward the diaphysis of the fetal canine long bone was apparent as the trabecular structures were remodeled to bone. Unexpectedly, type X collagen was also detected in the zone of calcified, mature articular cartilage. It was concentrated in the pericellular matrix of the chondrocytes, appeared at or just above the tidemark, and was expressed immediately before mineralization. Identification of type X collagen in both the canine growth plate and the zone of calcified articular cartilage suggests that cells in the deep layer of cartilage and in the zone of calcified cartilage in the adult animal retain some characteristics of a growth plate and may be involved in regulation of mineralization at this critical interface. The expression of growth plate-like properties would allow the deep chondrocytes of mature articular cartilage to play a role in remodeling of the joint with age and in the pathogenesis of osteoarthritis.
To our knowledge, this is the largest study examining the role of PET CT characteristics in esophageal adenocarcinoma for patients undergoing neoadjuvant chemoradiotherapy that demonstrates that δ SUV of less than 45% is associated with patients with residual disease but not CPR. Based on the findings from our study, the current recommendation is still surgical resection regardless of the posttherapy PET SUV in the primary tumor. However, our study highlights the ability to detect patients with residual disease and the need to critically evaluate these patients for consideration of additional therapies.
A total of 114 healthy female European team handball players in the elite to second division with no previous ACL injury, and the uninjured legs of 22 females with a unilaterally reconstructed ACL (the injury sustained while playing handball; mean time from reconstruction 15 months) were examined with a Biodex isokinetic testing device. Five extensions and flexions at lower speed (60°/s) and 15 repetitions at higher speed (240°/s) were performed. Gravity‐corrected peak torque values for flexion and extension were obtained, and hamstrings‐to‐quadriceps ratios (H/Q) were calculated at both speeds. Compared with the control group, the uninjured legs of the injury group showed 8% weaker quadriceps muscles and 14% higher H/Q ratios at higher speed. The other between‐group comparisons were not significant. These differences could have been developed by strength reduction after the injury in the noninjured limb due‐to‐insufficient rehabilitation, by a weaker musculature in the patient group already initially, or by both mechanisms. If the second option is true, the finding may indicate that weak quadriceps musculature is one of the risk factors for anterior cruciate ligament injuries. The study establishes additional normative data on hamstrings and quadriceps torque on high‐level female handball players.
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