The effect of stem cells in repairing growth plate injury: a systematic review and meta-analysis

Background: Multiple studies have focused on stem cell-based therapies for growth plate injury.However, the results are not consistent.Objectives: This systematic review and meta-analysis were performed to evaluate the effects of stem cells on growth plate healing.Methods: A detailed search of relevant studies was conducted in three databases including Pub med, Cochrane library, and Embase databases, using the following keywords: “growth plate” or “physis” AND “stem cell” from inception to November 10, 2021. The standard mean difference (SMD) and 95% confidence interval (CI) for each individual study were extracted from the original studies based on relevant data and pooled to obtain integrated estimates using random effects modeling.Results: A total of 6 studies were identified. The results demonstrated that the angular deformity in the stem cell group was significantly lower than that in the control group at 4, 8,12 and 16weeks. The length discrepancy represented the degree of shortening deformity. In the stem cell group, the shortening deformity was milder than that of the control group at 16weeks. Meanwhile, at 16 weeks after surgery, the higher histologic scores in the stem cell group indicated that stem cell can significantly improve the repair quality of growth plate.Conclusions: This systematic review and meta-analysis confirmed that stem cell improved the rehabilitation of growth plate injury. However, larger-scale studies are needed to further support these findings.

Youth Distance Running and Lower Extremity Injury: A Systematic Review

Distance running is a popular youth sport. This systematic review identified and examined the effects of youth distance running and lower extremity musculoskeletal injury. Scientific databases were searched from database inception to May 2020. Two hundred and fifty-eight full texts were screened, with nine articles retained for data extraction. Seven of the studies were case reports or case series. Two case reports involved an apophyseal hip fracture. No correlation was found between running mileage or gender and sustaining an injury. Middle school runners reported fewer injuries than high school runners. Cross country accounted for less than 10% of injuries in youth under 15 compared to other track activities. The main finding was a paucity of research. Available literature suggests youth can participate in distance running with minimal adverse effects. One exception may be increased vulnerability to growth plate injury. Additional research is needed, especially in those under 10, as literature in this population is nonexistent.

Emulsion-free chitosan–genipin microgels for growth plate cartilage regeneration

The growth plate is a cartilage tissue near the ends of children’s long bones and is responsible for bone growth. Injury to the growth plate can result in the formation of a ‘bony bar’ which can span the growth plate and result in bone growth abnormalities in children. Biomaterials such as chitosan microgels could be a potential treatment for growth plate injuries due to their chondrogenic properties, which can be enhanced through loading with biologics. They are commonly fabricated via an emulsion method, which involves solvent rinses that are cytotoxic. Here, we present a high throughput, non-cytotoxic, non-emulsion-based method to fabricate chitosan–genipin microgels. Chitosan was crosslinked with genipin to form a hydrogel network, and then pressed through a syringe filter using mesh with various pore sizes to produce a range of microgel particle sizes. The microgels were then loaded with chemokines and growth factors and their release was studied in vitro. To assess the applicability of the microgels for growth plate cartilage regeneration, they were injected into a rat growth plate injury. They led to increased cartilage repair tissue and were fully degraded by 28 days in vivo. This work demonstrates that chitosan microgels can be fabricated without solvent rinses and demonstrates their potential for the treatment of growth plate injuries.