Feasibility of pre- and postoperative arthroscopic assessments with internal fixation for growth plate injury of the distal tibia: three case reports and a literature review.

BACKGROUND: Inappropriate treatment of growth plate injury may cause complications such as malunion or early arrest of the growth plate. Identification of intra-articular lesions is mandatory in patients with a growth plate injury of the distal tibia. Arthroscopic assessment is useful in identifying intra-articular injury. We report three cases of intra-articular growth plate injury of the distal tibia that were treated via internal fixation with arthroscopic assessment in our hospital. MATERIALS AND METHODS: All three cases were performed pre- and postoperative arthroscopic assessment and open reduction and internal fixation with a cannulated cancellous screw (CCS; Meira, Japan). All patients were then examined for postoperative complications, functional recovery, at the end of the final follow-up consultation. RESULTS: Intraoperatively, a small cartilage injury was found in the non-fracture area in two cases; the remaining case had a reversed cartilage fragment at the talus, which was arthroscopically removed. CONCLUSIONS: Arthroscopic assessment followed by internal fixation is a useful minimally invasive method for the identification of intra-articular lesions such as osteochondral injury or free bodies.

Enhanced expression of PP1gamma1, a catalytic subunit isoform of protein phosphatase type1 and expression of telomerase activity in Ewing's sarcoma cells.

We previously reported that PP1gamma1 is highly expressed in osteosarcoma and chondrosarcoma, and suggested that this protein plays a role in malignancy of osteogenic tumors. In this study, we investigated the correlation of the expression of PP1gamma1 with telomerase activity. PP2A protein was not positive in any of the 5 cases of Ewing's sarcoma, but PP1gamma1 protein was strongly positive in all cases. Furthermore, malignant cells had high telomerase activity. We investigated the correlation of the expression of PP1gamma1 with telomerase activity, and showed that telomerase activity is regulated by protein phosphorylation in Ewing's sarcoma cells.