Results of a shuttle catheter technique for surgical repair of acute extensor hallucis longus tears.

Background and study aims: The proximal end of a torn Extensor hallucis longus (EHL) is usually so retracted that a proximal wound extension is always required to retrieve it; leading to more adhesions and stiffness. This study aims at assessment of a novel technique for proximal stump retrieval and repair of acute EHL injuries with no need for wound extension. Material and methods: Thirteen patients with acute EHL tendon injuries at zones III, IV were prospectively included in our series. Patients with underlining bony injuries, chronic tendon injuries and previous nearby skin lesions were excluded. Dual Incision Shuttle Catheter (DISC) technique was applied with subsequent evaluation by the American Orthopedic Foot and Ankle Society (AOFAS) hallux scale, Lipscomb and Kelly score, range of motion and muscle power. Results: Dorsiflexion at the metatarsophalangeal (MTP) joint significantly improved from a mean of 38.4±6.2º at one month to 58±9.6º at three months to 78.8±3.1º at one year postoperatively (P=0.0004). Plantar flexion at MTP joint significantly inclined from 16±3.8º at 3 months to 30.6±7.8º at the last follow-up (P=0.006). The big toe dorsiflexion power surged from 6.1±0.9N to 11.1±2.5N to 19.7±3.4N at 1 month, 3 months and one-year follow-up periods respectively (P=0.013). As per the AOFAS hallux scale, pain score was 40 of 40 points. The mean functional capability score was 43.7 out of 45 points. On Lipscomb and Kelly scale, all were graded "good" except for one patient who was graded "fair". Conclusion: Dual Incision Shuttle Catheter (DISC) technique represents a reliable method for repair of acute EHL injury at zones III, IV.

Coculturing of mesenchymal stem cells of different sources improved regenerative capability of osteochondral defect in the mature rabbit: An in vivo study.

PURPOSE: Choosing a therapeutic cell source for osteochondral repair remains a challenge. The present study investigated coculturing mesenchymal stem cells (MSCs) from different sources to provide an improved therapeutic cell option for osteochondral repair. METHODS: Dutch and Japanese white rabbits were used in this study, the first for isolating MSCs and the second for creating an osteochondral model in the medial femoral condyle. The 26 rabbit knees were divided randomly into four groups: control ( n = 6), bone marrow-derived MSCs (BMSCs) ( n = 7), synovial tissue MSCs (SMSCs) ( n = 7), and cocultured MSCs ( n = 6). Tissue repair was assessed using the Fortier scale, and colony-forming assay was performed. RESULTS: At different cell densities, cocultured and SMSCs formed larger colonies than BMSCs, indicating their high proliferative potential. After 2 months, complete filling of the defect with smooth surface regularity was detected in the cocultured MSC group, although there was no significant difference among the therapeutic groups macroscopically. Also, tissue repair was histologically better in the cocultured MSC group than in the control and SMSC groups, due to repair of the subchondral bone and coverage with hyaline cartilage. Additionally, toluidine blue and collagen-II staining intensity in the repaired tissue was better in the cocultured MSC group than in the remaining groups. CONCLUSION: Our results suggest that cocultured MSCs are a suitable option for the regeneration capability of osteochondral defects due to their enhanced osteochondrogenic potential.