To treat bone loss that is induced by disease or wounds, bone grafts are commonly used. In dentistry, guided tissue regeneration is effective in the treatment of periodontal diseases. However, bone resorption after implantation is a major problem with the bone graft and guided tissue regeneration technique. This study examines a cell pellet culture system without exogenous scaffolds for bone regeneration. First, we examined the effect of ascorbic acid on cells. Transmission electron microscopic observation revealed that cells formed a three-dimensional structure of multiple cell layers after 5 weeks of culturing in medium containing 50 µg/ ml ascorbic acid with the medium changed every 7 days. A single cell pellet was produced by centrifuging cells that were gathered from 10 tissue culture dishes. Van Gieson staining and collagen type I immunostaining showed that the pellet contained collagen fibers and cells that adhered to the collagen fibers. Several of these cell pellets were implanted subcutaneously on the backs of nude mice for 6 weeks. Histology and immunohistochemistry results indicated new bone formation, vascular invasion, and insular areas of calcification. Bone tissue was surrounded by osteoblasts. The appearance of new bone formation is similar to that seen in intramembranous ossification. The present pellet system is reliable and might solve problems of bone resorption after implantation.
This report describes two cases of traumatic closed index extensor tendon rupture at the musclotendinous junction. Both patients were injured when their work gloves were caught in the revolving parts of machines, and both were treated surgically. One of the patients completely ruptured the index extensor digitorum communis (EDC) and the extensor indicis proprius (EIP) tendons at the musclotendinous junction of dorsal forearm. In this patient, the distal stump of the index EDC tendon was sutured to the middle EDC tendon in an end-to-side juncture. The other patient completely ruptured the EIP tendon and partially ruptured the index EDC tendon at the musclotendinous junction. In this patient, tendon transfer of the extensor digiti minimi (EDM) to the EIP tendon and plication of the index EDC tendon were performed. In both cases, surgical intervention enabled the patients to extend their index fingers almost normally; however, the former complained of inability to extend his index finger independently. Tendon transfer of the EDM in cases of index extensor tendon rupture at the musclotendinous junction is a good method to restore ability to independently extend the index finger. However, consideration should be given to anatomical variation in the little finger. The EDC tendon is sometimes absent leaving the EDM tendon as the only extensor tendon to the little finger.
Fracture-dislocations of the proximal interphalangeal joint are challenging to treat, since it is difficult to achieve both rigid fixation and early joint motion simultaneously. Palmar fracture-dislocations of the proximal interphalangeal joint are less frequent injuries and a small number of treatment methods have been reported. We describe here a patient with a chronic palmar fracture-dislocation of the proximal interphalangeal joint, who was treated with a new surgical technique. In the surgery, a mini hook plate that was made by adapting a 1.5 mm AO hand modular system straight plate was used. Despite the thinness of the fragment, rigid fixation was achieved, resulting in early active motion. At final follow up, the active ranges of motion were 0°-100° at the proximal and 0°-80° at the distal interphalangeal joint, and there were no complications. This technique may become a useful surgical method to treat palmar fracture-dislocations of the proximal interphalangeal joint.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.