[Progress on the treatment of recurrent anterior dislocation of shoulder with bone defect]

Recurrent anterior dislocation of shoulder with bone defect is one of the common diseases of shoulder joint. How to effectively repair glenoid bone defect and reduce recurrence rate of shoulder dislocation is a problem that clinicians focus on. Bone grafting could stimulate bone, promote bone regeneration and bone remodeling, and restore the normal anatomical structure of glenoid. Among them, Bristow-Latarjet procedure is a classic operation for recurrent shoulder dislocation. Latarjet procedure could repair larger glenoid bone defects, but with higher surgical skills for surgeons;autogenous iliac grafting is the first choice for revision once Latarjet procedure failed;osteochondral grafting (autogenous and allogenous) has certain advantages in reconstructing original articular surface and preventing joint degeneration, but autologous osteochondral grafting may cause secondary injury, while immune rejection is difficult to avoid for allogenous osteochondral grafting. With the improvement of composite materials, and the mechanism of bone regeneration and remodeling, as well as the advantages and disadvantages of bone grafting, tissue engineering technology may become an effective method for the treatment of glenoid bone defect in the future.

[Follow-up study on autogenous osteochondral transplantation for cartilage defect of knee joint]

OBJECTIVE

To evaluate clinical effect of autologous osteochondral transplantation in treating localized knee cartilage defects.

METHODS

Fifteen patients with knee cartilage defects were treated by autologous osteochondral transplantation from January 2007 to January 2008, including 8 females and 7 males, aged from 23 to 45 years old. Preoperative and postoperative KSS score at 10 years were compared.

RESULTS

All patients were followed up for 10.0 to 10.7 years, with an average of(10.2±0.3) years. Clinical score of KSS was improved from 38.86±4.09 to 85.07±2.19 at 10 years after operation(P<0.05), functional score increased from 3.33±4.88 to 82.67±4.58 at 10 years after operation(P<0.05), KSS score was improved form 42.20±7.84 befor operation to 167.73±6.29 at 10 years after operation, and had statistical differences before and after operation. While there was no statistical difference in stability of knee joint(P>0.05). All patients had no other complications.

CONCLUSIONS

Through long-term follow-up of patients with cartilage defect in knee treated by autologous bone cartilage transplantation showed that this method could effectively improve function of knee joint and alleviate pain. So it is an effective method for repair of osteochondral defect.

Changes in expression of Wnt signaling pathway inhibitors dickkopf-1 and sclerostin before and after total joint arthroplasty

The aim is to study how serum concentration of Dickkopf-1 (DKK1) and Sclerostin (SOST) varies in patients before and after undergoing total joint arthroplasty (TJA). A total of 104 patients undergoing TJA were included in this study. Serum DKK1 and SOST were measured at 1 day before and 1, 3, and 5 days after surgery. DKK1 levels were highest at 5 days' postoperation, increasing to 25.17% above preoperation levels (P < .01), while SOST levels were lowest at 3 days' postoperation, falling to 18.71% below preoperation levels (P < .05). Serum levels of DKK1 and SOST showed opposite trends in the days following TJA. Our research describes for the first time the perioperative changes observed in serum DKK1 and SOST levels of osteoarthritis (OA) patients undergoing TJA. Increased DKK1 and decreased SOST levels may help maintain the equilibrium of the WNT pathway in OA patient's postsurgery.

Post annealing effect on the electrical properties of top-gate SWNT network transistors

High performance top-gate single walled carbon nanotube network transistors are fabricated with aluminum oxide (Al2O3) layer as a gate dielectric by atomic layer deposition. It exhibits large on/off ratio (>10(4)) due to selective growth of semiconducting tubes by the plasma enhanced chemical vapor deposition. I-V characteristics show p-type or n-type depending on the deposition temperature. We investigate the type dependent characteristics for the carrier polarities with the post annealing effect on the top-gate SWNT network transistors. The dramatic change in the polarity of the top-gate SWNT network transistors, from n-type to p-type due to conversion of I-V characteristics is observed by post-annealing at 350 degrees C for 30 minutes under vacuum. Our observation suggests that competition between electron transfer from the Al2O3 layers to the SWNT surface and electron capture by oxygen molecules adsorbed on the tube walls seems to be the key point for the V(th) change as a function of Al2O3 deposition temperature.