ABSTRACT
Objective To explore the histological changes of the wrist interosseous ligaments after radiofrequency electrothermal shrinkage. Methods Six frozen fresh male adult cadaver wrist ligaments were exploited for the research. The ligaments of the right wrists were treated with radiofrequency electrothermal shrinkage with Arthrocare system, while the ligaments of the left wrists were kept as the normal control. The bone-ligament-hone samples of all the scapholunate (SL) and lunotriquetral (LT) ligaments were prepared, sectioned and then stained with the regular HE staining, toluidine blue staining, Sirius-red staining and immunohistochemistry staining of collagen Ⅲ. The image analysis software was used to compare the staining results. Results The histological structures of SL dorsal ligaments (SL-d) and LT volar ligaments (LT-v) were very similar, and the structures of SL volar ligaments (SL-v) and LT dorsal ligaments (LT-d) were also very similar. The membrane parts of both SL and LT ligaments showed the fibrous cartilage structure. The histological structures of SL-d and LT-v were much less destroyed by the radiofrequency than those of SL-v and LT-d. After radiofrequency electrothermal shrinkage, only the distribution areas of collagen Ⅰ and collagen Ⅲ were significantly changed in the membrane parts of SL and LT ligaments. Conclusion Radiofrequency electrothermal shrinkage treatment can cause minor structural damage to the collagen-dominant ligaments such as SL-d and LT-v, while it can lead to quite severe structural damage to the ligaments containing collagen and lots of loose connective tissue, such as SL-v and LT-d.
ABSTRACT
BACKGROUND: Effect of acellular surfactant and biological safety of bone graft materials highly correlated with selection of surfactant; therefore, a novel compound surfactant was used to prepare acellular bone graft materials in this study. OBJECTIVE: To evaluate acellular effect and biological safety of bio-derived bone tissue treated by a novel surfactant in order to obtain a safe and reliable bone graft material. METHODS: Surfactant was prepared with anionic surfactant sodium dodecyl benzene sulfonate (ABS), anionic surfactant sodium fatty alcohol ether sulfate (AES) and distilled water at the ratio of 13:7:80. Fresh bovine cancellous bone and surfactant which was used to remove cells and lipid by two-step flow were used to prepare a novel bio-derived bone graft material. The histological and microscopic observations of microstructure were made. Also acute body toxicity test, hematolysis experiment, cell toxicity test and biological safety were assessed on surfactant-treated bio-dedved bone graft material (STBB). A long-term animal experiment was conducted to observe the biocompatibility and biodegradability of STBB. The ultraviolet dispersion of light luminosity method was employed to measure the residual amount of surfactant in STBB. RESULTS AND CONCLUSION: STBB was a whitish porous cancellous bone. No cell was found in bone lacuna, bone canaliculus was empty, and the collagen fiber had an order arrangement. Acute body toxicity test was qualified according to GB/116886.11-1997 standard, hematolysis experiment was < 5%, and cell toxicity test was grade 0, confirming that STBB was safe. The remaining surfactant in STBB was lower than 0.1 g/L. The long-term animal experiment demonstrated that fiber was present at 4 weeks, bone lacuna had cellular growth and the fusion of STBB and host appeared. The STBB was partial absorbed by organism at 8 weeks and completely absorbed at 24 hours. The results indicated that STBB had an excellent biocompatibility and biodegradability. As a new bone implant material, STBB was safe and dependable for transplantation.