In many diseases wound healing is impaired. This study was designed to establish whether the healing process in diabetes could be improved using a site-specific polymer delivery system containing hGH. The system was first optimized in in vitro experiments performed on cultured fibroblasts taken from healthy and diabetic rats and then tested in an incisional wound model created in the diabetic Wistar rat. In the in vitro experiments using cultured fibroblasts, cell viability, growth, and proliferation were determined, along with polymer degradation, hormone release rates and the expression of TGFbeta1 in the culture medium. For the in vivo experiments, polymer discs with/without GH were inserted through 3 cm incisions made on the backs of the animals. Wound specimens were obtained 7 and 30 days after surgery to evaluate inflammatory/apoptotic cells, metalloprotease expression and neoangiogenesis using microscopy and immunohistochemical techniques. The local administration of GH using a polymer delivery system did not affect the normal wound healing process. Conversely, when used in diabetic animals, epidermal and dermal repair was expedited. Our findings indicate that GH induces cell proliferation, enhances CD4(+) infiltration; increases extracellular matrix protein deposition; stimulates angiogenesis; and diminishes apoptosis at the diabetic wound site. These effects give rise to a comparable wound healing process to that observed in healthy animals.

Abstract-Controlled release systems for drugs, hormones and growth factors can be particularly useful in tissue repair processes. These systems act as a biodegradable support containing the substance to be delivered, allowing their gradual release. In the past years, the local application of growth factors has acquired special relevance as a therapeutic option for use in subjects who show de cient tissue scarring, the hormone dose being the limiting factor for its success. In this study, the in vitro biocompatibility of a copolymer formed by vinylpyrrolidone and 2-hydroxyethyl methacrylate, used as an administration vehicle for hGH, was evaluated. The system was then tested in vivo in terms of its capacity for healing incisional wounds in healthy and diabetic rats. For the in vitro studies, polymer and hormone degradation rates were determined, and polymer biocompatibility was evaluated in broblast cultures. In the in vivo experiments, an incision was made in the back of the animals, and polymers discs with/ without hGH, were introduced in the aperture. Morphological, immunohistochemical and morphometric evaluations were performed on wound tissue specimens 3-10 days after surgery. In vitro, the polymer was found to be biodegradable and showed no toxic effects on broblasts, the hormone being slowly released to the culture medium. In untreated diabetic rats, a delayed skin scarring and cell response were observed, compared to that noted in healthy animals. Skin closure, keratinisation and brosis occurred earlier in the presence of the polymer-hGH system. The use of this co-polymer as an administration vehicle for hGH improves the wound scarring process in the pathological setting of diabetes.

Background: Since the description of the arthroscopic Latarjet technique, discussion about the superiority of the open or arthroscopic procedure has arisen. The appropriate placement of the coracoid graft (CG) on the anterior glenoid neck is reported to be the most important step of the Latarjet procedure. Purpose: To verify if there are differences in the parameters that may affect the final position and fixation of CG obtained from the open and arthroscopic Latarjet techniques. Study Design: Controlled laboratory study. Methods: Twenty fresh-frozen human paired cadaveric shoulder specimens were randomly distributed in 2 surgery groups (open group [OG] and arthroscopic group [AG]) with 10 specimens in each. Two surgeons, each with experience performing open and arthroscopic Latarjet techniques, executed these procedures: one surgeon performed all open techniques, and the other performed all arthroscopic techniques, respectively. After surgery, a computerized tomography scan was performed. The surgical time, the position of each CG, a series of variables that might affect the CG fixation, and the level of the subscapularis muscle split were evaluated. Results: The mean surgical time was significantly longer in the AG (mean, 26 minutes for OG and 57 minutes for AG). Three intraoperative complications (30%) were identified in the AG, consisting of graft fractures. The CG was determined to be in an optimal cranial-caudal position in 90% of specimens of the OG and 44% of the AG (Fisher, P = .057). In both groups, the CG was placed in an optimal medial-lateral position in all specimens. In the OG, the degree of parallelism between the major axes of the glenoid surface and CG was significantly greater than in the AG (mean, 3.8º for OG and 15.1º for AG). No significant differences were observed in superior and inferior screw orientation between the groups. In the longitudinal and transverse directions, significant differences were found in the centering of the superior screw, being closer to the ideal point in the OG than in the AG. The location where the longitudinal subscapularis muscle split was performed was significantly higher in the AG. Conclusion: The open Latarjet technique required less surgical time; presented a lower number of intraoperative complications; and allowed more adequate placement of the CG, better centering of the screws, and a subscapularis muscle split closer to the ideal position. Clinical Relevance: The reported benefits of the arthroscopic Latarjet technique seem less clear if we take into account the added surgery time and complications.

The use of biomaterials as vehicles for pharmacological agents, hormones, and growth factors is at times the best treatment for controlled local administration. Our study was designed to evaluate the in vitro biocompatibility and potential clinical use of a new polymer, hydroxyethyl methacrylate-vinyl pirrolidone. Human fibroblasts were incubated in the presence of the polymer and/or growth hormone, and evaluation was made of both the rate of polymer and hormone degradation and the proliferative effect on the fibroblast population. Results indicate that this polymer is biodegradable and lacks toxicity toward these cells. The hormone was slowly released, as suggested by enhanced cell proliferation.

Instabilities of the subtalar joint are commonly overlooked or mismanaged, and chronic instability is a debilitating condition leading to premature joint degeneration. Several methods of treatment have been described, mainly screw fixation, arthrodesis, or ligament reconstruction. Most studies describe open methods for ligament reconstruction. We describe an original technique for "all-inside" arthroscopic graft reconstruction of the interosseous talocalcaneal ligament for subtalar instability.