ABSTRACT
BACKGROUND: The optimal surgical treatment for Kienböck's disease with stages IIIB and IV remains controversial. A cadaver study was carried out to evaluate the use of coiled extensor carpi radialis longus tendon for tendon interposition and a strip obtained from the same tendon for ligament reconstruction in the late stages of Kienböck's disease. METHODS: Coiled extensor carpi radialis longus tendon was used to fill the cavity of the excised lunate, and a strip obtained from this tendon was sutured onto itself after passing through the scaphoid and the triquetrum acting as a ligament to preserve proximal row integrity. Biomechanical tests were carried out in order to evaluate this new ligamentous reconstruction. RESULTS: It was biomechanically confirmed that the procedure was effective against axial compression and distributed the upcoming mechanical stress to the distal row. CONCLUSION: Extensor carpi radialis longus tendon has not been used for tendon interposition and ligament reconstruction in the treatment of this disease before. In view of the biomechanical data, the procedure seems to be effective for the stabilization of scaphoid and carpal bones.
Subject(s)
Osteonecrosis/surgery , Plastic Surgery Procedures/methods , Tendon Transfer/methods , Tendons/transplantation , Wrist Joint/surgery , Cadaver , Humans , Treatment OutcomeABSTRACT
BACKGROUND: Fracture healing is a significant process in orthopedics. In this controlled animal study, our aimis to expose the healing effects of cord blood umbilico-placental mononuclear cells (UPMNCs) on bone fractures. MATERIALS AND METHODS: Caesarean sections were performed on five pregnant New Zealand rabbits at term. Placentas and cords were collected. Standard closed transverse shaft fractures were created on both tibial bones of 15 baby rabbits. The right tibias were given UPMNCs; the left tibias were the control group. Histological examinations, osteoblast and osteoclast cell counts, and mechanical stabilities were compared. Anchorage of the donor cells was shown by the fluorescence in situ hybridization (FISH) technique. RESULTS: In the group injected with UPMNCs, histopathological fracture healing was faster, osteoblast and osteoclast counts were significantly increased, and the maximum load capacity was higher. The presence of XX and XY chromatins on the same slide revealed the anchorage of female donor cells on male tissues. CONCLUSION: The effects of umbilico-placental mononuclear cells on bone healing are histopathological healing priority, increased osteoblastic and osteoclastic activities (bone turnover), and better mechanical stability.
ABSTRACT
OBJECTIVES: We investigated the effect of low-molecular-weight heparin (LMWH) on the healing of tendons. METHODS: Forty-five adult Wistar rats weighing 300 g were randomized into three groups equal in number. All the rats underwent full-thickness surgical incision of the Achilles tendon followed by primary repair. After the operation, two groups received daily subcutaneous LMWH injections (nadroparin calcium) for four weeks at high or low doses (group I, 6 mg/kg, 170 IU AXa; group II, 3 mg/kg, 85 IU AXa). Group III remained untreated as the control group. Histologically, the specimens were examined under light and electron microscopy with regard to the amount of fibrillar collagen synthesis, mitochondrial degeneration, and the composition of the extracellular matrix collagen. Biomechanically, maximum load to failure and correspondent elongation of the tendons were measured. RESULTS: Compared to the control group, histologically, both LMWH-treated groups exhibited increased number of fibroblasts, increased fibrillar collagen formation in the extracellular matrix, and higher counts of granular endoplasmic reticula in cytoplasmic contents of fibroblasts as well as decreased mitochondrial vacuolization and degeneration. Biomechanical assessments showed that tendons in group I had significantly higher maximum load to failure and elongation values than group II and III (31 N vs. 24.6 N and 23.1 N; 25 mm vs. 19.6 mm and 17.3 mm, respectively; p<0.05). Groups II and III did not differ significantly in this respect (p>0.05). CONCLUSION: Daily administration of single dose LMWH improves tendon healing through increasing the number of fibroblasts and fibrillar collagen synthesis and decreasing mitochondrial degeneration.
