BACKGROUND: Osteoporosis, characterized by decreased bone mineral density due to an imbalance between osteoblast and osteoclast activity, poses significant challenges in bone healing, particularly in postmenopausal women. Current treatments, such as bisphosphonates, are effective but associated with adverse effects like medication-related osteonecrosis of the jaw, necessitating safer alternatives. METHODS: This study investigated the use of L-serine-incorporated gelatin sponges for bone regeneration in calvarial defects in an ovariectomized rat model of osteoporosis. Thirty rats were divided into three groups: a control group, a group treated with a gelatin sponge containing an amino acid mixture, and a group treated with a gelatin sponge containing L-serine. Bone regeneration was assessed using micro-computed tomography (micro-CT) and histological analyses. RESULTS: The L-serine group showed a significant increase in bone volume (BV) and bone area compared to the control and amino acid groups. The bone volume to total volume (BV/TV) ratio was also significantly higher in the L-serine group.Immunohistochemical analysis demonstrated that L-serine treatment suppressed the expression of cathepsin K, a marker of osteoclast activity, while increasing serine racemase activity. CONCLUSION These findings suggest that L-serine-incorporated gelatin sponges not only enhance bone formation but also inhibit osteoclast-mediated bone resorption, providing a promising and safer alternative to current therapies for osteoporosis-related bone defects. Further research is needed to explore its clinical applications in human patients.

Background: Allografts are preferred in certain cases of revision anterior cruciate ligament reconstructions to avoid additional graft harvesting and to fill in enlarged tunnels. The clinical outcomes of quadriceps tendon-patellar bone allograft in revision anterior cruciate ligament reconstruction are not well-known. This study was performed to evaluate the clinical outcomes of revision anterior cruciate ligament reconstructions using quadriceps tendon-patellar bone allografts. Methods: Patients who underwent revision anterior cruciate ligament reconstructions with quadriceps tendon-patellar bone allografts with a minimum follow-up of 2 years were retrospectively reviewed. Their mean follow-up length was 33.5 ± 19.5 months.Outcomes including clinical scores (Lysholm, International Knee Documentation Committee [IKDC], Tegner scale, and Knee injury and Osteoarthritis Outcome Score [KOOS]), knee stability (physical examinations and knee arthrometer), return to sports, and any associated complications were assessed. Degrees of graft synovialization were also evaluated using arthroscopy. Results: A total of 38 patients were reviewed and their age at the time of surgery and follow-up length were 37.2 ± 12.5 years (range, 17–66 years) and 2.8 ± 1.6 years, respectively. All clinical scores including KOOS, IKDC, Lysholm, and Tegner scale significantly improved at 2 years after surgery and 92.1% of the patients returned to sports. The mean preoperative side-to-side difference in knee arthrometer decreased from 4.5 ± 2.3 mm before surgery to 2.6 ± 1.5 mm after surgery (p < 0.001). Graft synovialization was observed in 13 of 16 patients (81.3%) who underwent second-look arthroscopy. Complication rate was 10.5% (n = 4). All complications were graft re-rupture and occurred at an average of 18 months after revision surgery. Conclusions Quadriceps tendon-patellar bone allograft showed satisfactory clinical outcomes in revision anterior cruciate ligament reconstruction and thus could be a good alternative when autograft harvesting is not optimal.

BACKGROUND: Osteoporosis, characterized by decreased bone mineral density due to an imbalance between osteoblast and osteoclast activity, poses significant challenges in bone healing, particularly in postmenopausal women. Current treatments, such as bisphosphonates, are effective but associated with adverse effects like medication-related osteonecrosis of the jaw, necessitating safer alternatives. METHODS: This study investigated the use of L-serine-incorporated gelatin sponges for bone regeneration in calvarial defects in an ovariectomized rat model of osteoporosis. Thirty rats were divided into three groups: a control group, a group treated with a gelatin sponge containing an amino acid mixture, and a group treated with a gelatin sponge containing L-serine. Bone regeneration was assessed using micro-computed tomography (micro-CT) and histological analyses. RESULTS: The L-serine group showed a significant increase in bone volume (BV) and bone area compared to the control and amino acid groups. The bone volume to total volume (BV/TV) ratio was also significantly higher in the L-serine group.Immunohistochemical analysis demonstrated that L-serine treatment suppressed the expression of cathepsin K, a marker of osteoclast activity, while increasing serine racemase activity. CONCLUSION These findings suggest that L-serine-incorporated gelatin sponges not only enhance bone formation but also inhibit osteoclast-mediated bone resorption, providing a promising and safer alternative to current therapies for osteoporosis-related bone defects. Further research is needed to explore its clinical applications in human patients.

BACKGROUND: Osteoporosis, characterized by decreased bone mineral density due to an imbalance between osteoblast and osteoclast activity, poses significant challenges in bone healing, particularly in postmenopausal women. Current treatments, such as bisphosphonates, are effective but associated with adverse effects like medication-related osteonecrosis of the jaw, necessitating safer alternatives. METHODS: This study investigated the use of L-serine-incorporated gelatin sponges for bone regeneration in calvarial defects in an ovariectomized rat model of osteoporosis. Thirty rats were divided into three groups: a control group, a group treated with a gelatin sponge containing an amino acid mixture, and a group treated with a gelatin sponge containing L-serine. Bone regeneration was assessed using micro-computed tomography (micro-CT) and histological analyses. RESULTS: The L-serine group showed a significant increase in bone volume (BV) and bone area compared to the control and amino acid groups. The bone volume to total volume (BV/TV) ratio was also significantly higher in the L-serine group.Immunohistochemical analysis demonstrated that L-serine treatment suppressed the expression of cathepsin K, a marker of osteoclast activity, while increasing serine racemase activity. CONCLUSION These findings suggest that L-serine-incorporated gelatin sponges not only enhance bone formation but also inhibit osteoclast-mediated bone resorption, providing a promising and safer alternative to current therapies for osteoporosis-related bone defects. Further research is needed to explore its clinical applications in human patients.

Background: Allografts are preferred in certain cases of revision anterior cruciate ligament reconstructions to avoid additional graft harvesting and to fill in enlarged tunnels. The clinical outcomes of quadriceps tendon-patellar bone allograft in revision anterior cruciate ligament reconstruction are not well-known. This study was performed to evaluate the clinical outcomes of revision anterior cruciate ligament reconstructions using quadriceps tendon-patellar bone allografts. Methods: Patients who underwent revision anterior cruciate ligament reconstructions with quadriceps tendon-patellar bone allografts with a minimum follow-up of 2 years were retrospectively reviewed. Their mean follow-up length was 33.5 ± 19.5 months.Outcomes including clinical scores (Lysholm, International Knee Documentation Committee [IKDC], Tegner scale, and Knee injury and Osteoarthritis Outcome Score [KOOS]), knee stability (physical examinations and knee arthrometer), return to sports, and any associated complications were assessed. Degrees of graft synovialization were also evaluated using arthroscopy. Results: A total of 38 patients were reviewed and their age at the time of surgery and follow-up length were 37.2 ± 12.5 years (range, 17–66 years) and 2.8 ± 1.6 years, respectively. All clinical scores including KOOS, IKDC, Lysholm, and Tegner scale significantly improved at 2 years after surgery and 92.1% of the patients returned to sports. The mean preoperative side-to-side difference in knee arthrometer decreased from 4.5 ± 2.3 mm before surgery to 2.6 ± 1.5 mm after surgery (p < 0.001). Graft synovialization was observed in 13 of 16 patients (81.3%) who underwent second-look arthroscopy. Complication rate was 10.5% (n = 4). All complications were graft re-rupture and occurred at an average of 18 months after revision surgery. Conclusions Quadriceps tendon-patellar bone allograft showed satisfactory clinical outcomes in revision anterior cruciate ligament reconstruction and thus could be a good alternative when autograft harvesting is not optimal.

Background: Allografts are preferred in certain cases of revision anterior cruciate ligament reconstructions to avoid additional graft harvesting and to fill in enlarged tunnels. The clinical outcomes of quadriceps tendon-patellar bone allograft in revision anterior cruciate ligament reconstruction are not well-known. This study was performed to evaluate the clinical outcomes of revision anterior cruciate ligament reconstructions using quadriceps tendon-patellar bone allografts. Methods: Patients who underwent revision anterior cruciate ligament reconstructions with quadriceps tendon-patellar bone allografts with a minimum follow-up of 2 years were retrospectively reviewed. Their mean follow-up length was 33.5 ± 19.5 months.Outcomes including clinical scores (Lysholm, International Knee Documentation Committee [IKDC], Tegner scale, and Knee injury and Osteoarthritis Outcome Score [KOOS]), knee stability (physical examinations and knee arthrometer), return to sports, and any associated complications were assessed. Degrees of graft synovialization were also evaluated using arthroscopy. Results: A total of 38 patients were reviewed and their age at the time of surgery and follow-up length were 37.2 ± 12.5 years (range, 17–66 years) and 2.8 ± 1.6 years, respectively. All clinical scores including KOOS, IKDC, Lysholm, and Tegner scale significantly improved at 2 years after surgery and 92.1% of the patients returned to sports. The mean preoperative side-to-side difference in knee arthrometer decreased from 4.5 ± 2.3 mm before surgery to 2.6 ± 1.5 mm after surgery (p < 0.001). Graft synovialization was observed in 13 of 16 patients (81.3%) who underwent second-look arthroscopy. Complication rate was 10.5% (n = 4). All complications were graft re-rupture and occurred at an average of 18 months after revision surgery. Conclusions Quadriceps tendon-patellar bone allograft showed satisfactory clinical outcomes in revision anterior cruciate ligament reconstruction and thus could be a good alternative when autograft harvesting is not optimal.

BACKGROUND: Osteoporosis, characterized by decreased bone mineral density due to an imbalance between osteoblast and osteoclast activity, poses significant challenges in bone healing, particularly in postmenopausal women. Current treatments, such as bisphosphonates, are effective but associated with adverse effects like medication-related osteonecrosis of the jaw, necessitating safer alternatives. METHODS: This study investigated the use of L-serine-incorporated gelatin sponges for bone regeneration in calvarial defects in an ovariectomized rat model of osteoporosis. Thirty rats were divided into three groups: a control group, a group treated with a gelatin sponge containing an amino acid mixture, and a group treated with a gelatin sponge containing L-serine. Bone regeneration was assessed using micro-computed tomography (micro-CT) and histological analyses. RESULTS: The L-serine group showed a significant increase in bone volume (BV) and bone area compared to the control and amino acid groups. The bone volume to total volume (BV/TV) ratio was also significantly higher in the L-serine group.Immunohistochemical analysis demonstrated that L-serine treatment suppressed the expression of cathepsin K, a marker of osteoclast activity, while increasing serine racemase activity. CONCLUSION These findings suggest that L-serine-incorporated gelatin sponges not only enhance bone formation but also inhibit osteoclast-mediated bone resorption, providing a promising and safer alternative to current therapies for osteoporosis-related bone defects. Further research is needed to explore its clinical applications in human patients.

Background: Allografts are preferred in certain cases of revision anterior cruciate ligament reconstructions to avoid additional graft harvesting and to fill in enlarged tunnels. The clinical outcomes of quadriceps tendon-patellar bone allograft in revision anterior cruciate ligament reconstruction are not well-known. This study was performed to evaluate the clinical outcomes of revision anterior cruciate ligament reconstructions using quadriceps tendon-patellar bone allografts. Methods: Patients who underwent revision anterior cruciate ligament reconstructions with quadriceps tendon-patellar bone allografts with a minimum follow-up of 2 years were retrospectively reviewed. Their mean follow-up length was 33.5 ± 19.5 months.Outcomes including clinical scores (Lysholm, International Knee Documentation Committee [IKDC], Tegner scale, and Knee injury and Osteoarthritis Outcome Score [KOOS]), knee stability (physical examinations and knee arthrometer), return to sports, and any associated complications were assessed. Degrees of graft synovialization were also evaluated using arthroscopy. Results: A total of 38 patients were reviewed and their age at the time of surgery and follow-up length were 37.2 ± 12.5 years (range, 17–66 years) and 2.8 ± 1.6 years, respectively. All clinical scores including KOOS, IKDC, Lysholm, and Tegner scale significantly improved at 2 years after surgery and 92.1% of the patients returned to sports. The mean preoperative side-to-side difference in knee arthrometer decreased from 4.5 ± 2.3 mm before surgery to 2.6 ± 1.5 mm after surgery (p < 0.001). Graft synovialization was observed in 13 of 16 patients (81.3%) who underwent second-look arthroscopy. Complication rate was 10.5% (n = 4). All complications were graft re-rupture and occurred at an average of 18 months after revision surgery. Conclusions Quadriceps tendon-patellar bone allograft showed satisfactory clinical outcomes in revision anterior cruciate ligament reconstruction and thus could be a good alternative when autograft harvesting is not optimal.

BACKGROUND: Osteoporosis, characterized by decreased bone mineral density due to an imbalance between osteoblast and osteoclast activity, poses significant challenges in bone healing, particularly in postmenopausal women. Current treatments, such as bisphosphonates, are effective but associated with adverse effects like medication-related osteonecrosis of the jaw, necessitating safer alternatives. METHODS: This study investigated the use of L-serine-incorporated gelatin sponges for bone regeneration in calvarial defects in an ovariectomized rat model of osteoporosis. Thirty rats were divided into three groups: a control group, a group treated with a gelatin sponge containing an amino acid mixture, and a group treated with a gelatin sponge containing L-serine. Bone regeneration was assessed using micro-computed tomography (micro-CT) and histological analyses. RESULTS: The L-serine group showed a significant increase in bone volume (BV) and bone area compared to the control and amino acid groups. The bone volume to total volume (BV/TV) ratio was also significantly higher in the L-serine group.Immunohistochemical analysis demonstrated that L-serine treatment suppressed the expression of cathepsin K, a marker of osteoclast activity, while increasing serine racemase activity. CONCLUSION These findings suggest that L-serine-incorporated gelatin sponges not only enhance bone formation but also inhibit osteoclast-mediated bone resorption, providing a promising and safer alternative to current therapies for osteoporosis-related bone defects. Further research is needed to explore its clinical applications in human patients.

Background: During total knee arthroplasty (TKA), patellar retention is performed when the cartilage is fairly well preserved and the thickness of the patella is relatively thin. However, clinical outcomes of the non-resurfaced patella in TKA according to the cartilage status are lacking in the literature. The purpose of this study was to compare patient-reported outcome measures (PROMs) according to the grade and location of the patellar cartilage lesion in TKA patients. Methods: The outcomes of 165 osteoarthritis patients (186 knees) who underwent cemented mobile-bearing TKA without patellar resurfacing were assessed and classified according to the grade and location of the patellar cartilage lesion. PROMs using the Western Ontario and MacMaster Universities Osteoarthritis index, the Knee Society Score (Knee Society Function Score and Knee Society Knee Score), and the Hospital for Special Surgery score were evaluated preoperatively and at postoperative 2, 4, 6, and 8 years. The correlations between PROMs and the grade and location of the cartilage lesion were assessed. Additionally, radiologic outcomes including the patellar tilt angle and patellar height were assessed and their correlation with the grade of cartilage lesion was analyzed. Analysis of variance was used to determine statistical significance. Results: There was no significant difference between PROMs according to the grades and locations of cartilage lesions at any postoperative follow-up. Radiologic parameters also showed no significant differences according to the grades of patellar cartilage lesions. Conclusions The grade and location of the patellar cartilage lesion had no influence on clinical outcomes in mobile-bearing TKA with patellar retention at short- and long-term follow-up.