Background: Osteoarthritis (OA) is a prevalent and disabling disease that affects a significant proportion of the global population. Urine-derived stem cells (USCs) have shown great prospects in the treatment of OA, but there is no study that has compared them with traditional stem cells.
Purpose: This study aimed to compare the therapeutic efficacy and mechanisms of USCs and adipose-derived stem cells (ADSCs) for OA treatment.
Study design: Controlled laboratory study.
Methods: We compared the biological properties of USCs and ADSCs using CCK-8, colony formation, EdU, adhesion, and apoptosis assays. We evaluated the protective effects of USCs and ADSCs on IL-1β-treated OA chondrocytes by chemical staining, immunofluorescence, and Western blotting. We assessed the effects of USCs and ADSCs on chondrocyte autophagy by transmission electron microscopy, immunofluorescence, and Western blotting. We also compared the therapeutic efficacy of intra-articular injections of USCs and ADSCs by gross, histological, micro-computed tomography, and immunohistochemical analyses in an OA rat model induced by anterior cruciate ligament transection.
Results: USCs showed higher proliferation, colony formation, DNA synthesis, adhesion, and anti-apoptotic abilities than ADSCs. Both USCs and ADSCs increased the expression of cartilage-specific proteins and decreased the expression of matrix degradation-related proteins and inflammatory factors in OA chondrocytes. USCs had a greater advantage in suppressing MMP-13 and inflammatory factors than ADSCs. Both USCs and ADSCs enhanced autophagy in OA chondrocytes, with USCs being more effective than ADSCs. The autophagy inhibitor 3-MA reduced the enhanced autophagy and protective effects of USCs and ADSCs on OA chondrocytes.
Conclusion: To our knowledge, this is the first study to explore the efficacy of USCs in the treatment of knee OA and to compare them with ADSCs. Considering the superior properties of USCs in terms of noninvasive acquisition, a high cost-benefit ratio, and low ethical concerns, our study suggests that they may be a more promising therapeutic option than ADSCs for OA treatment under rigorous regulatory pathways.
Clinical relevance: USCs may be a superior cell source for stem cells to treat knee OA, and this study strengthens the evidence for the application of USCs.
Background: Softball pitchers frequently pitch at high volumes. Previous research has demonstrated changes in mechanics, range of motion, and perceived levels of fatigue and pain at high workloads. To date, little research has assessed changes in kinetics at high workloads across pitch types to understand the injury risk.
Purpose: To examine changes in peak kinetics of the shoulder, elbow, and wrist of the pitching arm throughout a simulated game and doubleheader inning.
Study design: Descriptive laboratory study.
Methods: A total of 19 high school softball pitchers (mean age, 15.1 ± 1.5 years; mean height, 1.6 ± 0.2 m; mean weight, 76.3 ± 16.9 kg) participated. Pitchers threw 4 innings of 25 randomly assigned pitches to mimic a game's high pitch count. Participants then rested for 30 minutes before subsequently proceeding to pitch the first inning of a doubleheader. Each pitcher threw a fastball, drop ball, curveball, and changeup. Peak shoulder, elbow, and wrist kinetics were compared across the first, last, and doubleheader innings and pitch types.
Results: Compared with the first inning, significant decreases in kinetics were observed at the shoulder, elbow, and wrist in the last (P < .016) and doubleheader (P < .016) innings, particularly for shoulder and elbow compression force during the drop ball and curveball pitch types and wrist net force for all pitch types but the changeup. Significant decreases in elbow and wrist kinetics were observed during the changeup between the last and doubleheader innings (P < .016). Furthermore, differences in kinetics were observed between pitch types (P < .008); notably, the changeup had reduced kinetics compared with the fastball and breaking ball pitch types (drop ball, curveball) across innings.
Conclusion: Across innings, attenuations in select joint kinetics of the pitching arm occurred that were specific to the pitch type. Across pitch types, peak kinetics was often greater during the fastball, while the changeup displayed the lowest peak kinetics.
Clinical relevance: The joints examined in this study are common sites of overuse injuries in pitchers. This work adds to previous findings on decrements in neuromuscular function as well as self-reported fatigue and pain with tournament-style pitching that may increase the injury risk. Collectively, these findings support developing a protocol combining functional testing and player-reported outcomes to aid sports specialists' decisions for pitchers to continue to pitch or return to play, which may help prevent musculoskeletal injuries and time loss from sports participation.
Background: Bone marrow stimulation (BMS) has been proposed to augment healing at the time of arthroscopic rotator cuff repair (ARCR) by creating several bone marrow vents in the footprint of the rotator cuff, allowing mesenchymal stem cells, platelets, and growth factors to cover the area as a "crimson duvet."
Purpose: To perform a meta-analysis of randomized controlled trials (RCTs) to compare the outcomes after BMS and a control for those undergoing ARCR.
Study design: Meta-analysis; Level of evidence, 1.
Methods: A literature search of 3 databases was performed based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. RCTs comparing BMS and a control for ARCR were included. Clinical outcomes were compared, and a P value <.05 was considered to be statistically significant.
Results: A total of 7 RCTs with 576 patients were included. Overall, 18.8% of patients treated with BMS and 21.0% of patients treated with a control had a retear (I2 = 43%; P = .61). With BMS, the mean Constant score was 88.2, and with the control, the mean Constant score was 86.7 (P = .12). Additionally, there was no significant difference in the American Shoulder and Elbow Surgeons score (94.3 vs 93.2, respectively; P = .31) or visual analog scale score (0.9 vs 0.9, respectively; P = .89).
Conclusion: The level 1 evidence in the literature did not support BMS as a modality to improve retear rates or clinical outcomes after ARCR.