Effects of RGD Protein on the Bone Resorptive Activity of Osteoclast / 대한정형외과학회잡지

Osteoclasts resorb bone by the hydrogen ions and proteolytic enzymes in the localize environment under the ruffled border. Before releasing hydrogen ion and enzymes, osteoclast should attach to bone surface very tightly and make a room to release enzymes and hydrogen ion in the center. Specialized attachment molecule in the cell membrane, such as integrin, is associated with specific noncollagenous protein in the matrix, which has specific amino acid sequence (Arginine-Glycine- Aspartic acid sequence). We may speculate that osteoclast action would be decreased if the integrin is blocked by antibody or RGD protein. In this study, the osteoclasts were cultured on the coverslip or bone slice with or without RGD protein in the culture medium, and numbers of growing giant cells were much less in group with RGD protein. The number resorption pits, formed on mineralized bone slice, was also lower in the group adding RGD protein in the medium. And we made a conclusion that the osteoclastic bone resorption was inhibited by soluble RGD protein.

Early Results of Percutaneous Ilioscral Screw Fixation in Unstable Posterior Pelvic Ring Injury / 대한정형외과학회잡지

In the past two decades, open reduction and internal fixation has been the preferred treatment of posterior pelvic ring disruption with instability. Despite of rigid fixation, it can induce bleeding, wound infection, wound necrosis and prolong operation time in the patient with combined injuries. To compensate for these disadvantages, we have implemented closed reduction and percutaneous iliosacral fixation under fluoroscopy in reducible posterior pelvic ring disruption. In spite of anatomical risk during screw insertion, the percutaneous iliosacral screw technique after closed reduction of the posterior pelvic ring disruption minimally violates the soft tissue envelope and reduces both the operative blood loss and infection rate. We are reporting the early results of our 6 patients treated between Aug. 1995 to Aug. 1996. The operation time was shorter than open reduction and internal fixation. There was no significant bleeding, wound infection and nerve injury by screws.

A Clinical Study of Supracondylar Fracture of the Humerus in Children / 대한정형외과학회잡지

Supracondylar fracture of humerus is the most common fracture about the elbow in children and much has been written about its treatment and the prevention of both Volkmann's ischemia with contracture and cubitus varus deformity. In a retrospective survey of 155 children with supracondylar frscture of the humerus, 63 cases were found to have sufficient clinical and retrospective data to classify the fracture. 1. The average age was 6.5 years ranged from 1 year 3 months to 14 years and sex ratio was 2.2: 1(M:F) 2. 62 cases(98.4%) were extension type and 1 case(1.6%) was flexion type. In extension type, displacement was posteromedial 30 cases(47.6%), posterolatera117 cases(26.9%), posterior 10 cases(15.9%) and undisplaced 5 cases(7.9%). 3. Fracture level was divided into 3 Groups. Trans-olecranon fractures were 47 cases(74.6%), proximal to olecranon fractures were 11 cases(17.5%) and distal to olecranon fractures were 5 cases(7.9%). According to age distribution lower age group involves the distal part and higher age group involves proximal part. 4. Transverse fractures were 39 cases(61.9%) and oblique fractures were 24 cases(38.1%). In oblique fracture, postero-anterial oblique fractures were 19 cases(30.2%), medio-lateral oblique fractures 3 cases(4.8%), and latero-medial 2 cases(3.2%). In oblique fractures redisplacements were more common in P-A oblique csse. 5. In the treatment of fracture, 31 cases(49.2%) were treated with closed reduction and percutaneous pinning, 26 cases(41.3%) were treated with closed reduction and splint immobilization, 3 cases(4.8%) were treated with open reduction and K-wire fixation, 3 cases(4.8%) were treated with skeletal traction. 6. Functional results according to degree of initial displacement was worse in some displaced(Grade II) cases, rather than total displaced (Grade IV) or displaced with rotation (Grade III) cases. 7. Complications in splint immobilzation method were cubitus varus deformity 2 cases, nerve injury 2 case, and in k-wire fixation method, nerve injury 5 cases and pin migration 1 case.

An Experimental Study of Silastic Cuff Wrapping Around the Severed Peripheral Nerve / 대한정형외과학회잡지

The authors conducted an in-Vivo experimental study using sciatic nerve of 200-300 grammed rats to verify clinical applicability of Silicone cuffing method, by which scar adhesion of repaired nerve in crushed limb is assumed hopefully to be reduced. The following observations were obtainable. 1. Nerve conduction velocity was noted faster in Silicone cuff group than in control group significantly after 6 weeks postoperatively. 2. Adhesion of repaired nerve with surrounding scar tissue was far less present in Silicone cuff group than in control group when observed grossly. 3. The amount of scar formation and axonal degeneration were noted reduced remarkably in Silicone cuff group than in control group after 3 weeks postoperatively. 4. The intraneural vascularity was noted reduced either in Silicone cuff group and in control group, but definitely less reduced in the former than in the latter. Clinical relevance: Above results may be taken as an experimental basis supporting clinical applicability of Silicone cuff wrapping method for neurorraphy in crushed limb.