Simultaneous bilateral patellar tendon rupture without predisposing systemic disease or steroid use: a case report / 中华创伤杂志(英文版)

There is a dearth of case reports describing simultaneous bilateral patellar tendon ruptures in the medical literature. These ruptures are often associated with systemic disorders such as lupus erythematosus or chronic steroid use. The author describes a case of a 24-year-old man who sustained traumatic bilateral patellar tendon ruptures without any history of systemic disease or steroidal medication. We repaired and reattached the ruptured tendons to the patella and augmented our procedure with allogeneic tendon followed by wire loop reinforcement. One year after operation, the patient regained a satisfactory range of motion of both knees with good quadriceps strength and no extensor lag. The recurrent microtrauma from a history of intense sports activity and a high body mass index may have played an important role in this trauma event.

Whole meniscus regeneration using polymer scaffolds loaded with fibrochondrocytes / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To study the feasibility of regenerating a whole menisci using poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) scaffolds loaded with meniscal cells in rabbits undergoing total meniscectomy, and to explore its protective effect on cartilage degeneration.</p><p><b>METHODS</b>A solvent casting and particulate leaching technique was employed to fabricate biodegradable PHBV scaffolds into a meniscal shape. The proliferated meniscal cells were seeded onto the polymer scaffolds, transplanted into rabbit knee joints whose lateral menisci had been removed. Eight to 18 weeks after transplantation, the rege- nerated neomenisci were evaluated by gross and histological observations. Cartilage degeneration was assessed by Mankin score.</p><p><b>RESULTS</b>Eighteen weeks after transplantation, the implants formed neomenisci. Hematoxylin and eosin (HE) staining of the neomenisci sections revealed regeneration of fibrocartilage. Type I collagen in the neomenisci was also proved similar to normal meniscal tissue by immunohistochemical analysis and Sirius scarlet trinitrophenol staining. Articular cartilage degeneration was observed 8 weeks after implantation. It was less severe as compared with that in total meniscectomy controls and no further degeneration was observed at 18 weeks. At that time, the regenerated neomenisci strongly resembled normal meniscal fibrocartilage in gross and histological appearance, and its mechanical property was also close to that of normal meniscus.</p><p><b>CONCLUSIONS</b>The present study demonstrates the feasibility of tissue-engineering a whole meniscal structure in total meniscectomy rabbit models using biodegradable PHBV scaffolds together with cultured allogeneic meniscal cells. Cartilage degeneration is decreased. But long-term in vivo investigations on the histological structure and cartilage degeneration of the neomenisci regenerated by this method are still necessary to determine the clinical potential of this tissue engineering avenue.</p>

Treatment of tibial avulsion fracture of the posterior cruciate ligament with open reduction and steel-wire internal fixation / 中国骨伤

<p><b>OBJECTIVE</b>To study the curative effects of the treatment of tibial avulsion fracture of the posterior cruciate ligament with open reduction and steel-wire internal fixation.</p><p><b>METHODS</b>From January 2003 to June 2009, 28 patients of tibial avulsion fracture of the posterior cruciate ligament were treated with open reduction and steel-wire internal fixation through posteromedial inverted "L" approach. There were 19 males and 9 females with an average age of 35.3 years old ranging from 16 to 55 years. The X-ray examination showed that there were II degree displaced in 10 cases and III degree in 18 patients. The affected lower extremity was put in a controlled hinge knee brace after operation. The patients were asked to do passive extension and flexion of the knee joint with the assistance of a CPM 2 weeks after operation,and allowed to be partial weight-bearing as tolerated with the hinged brace locked in extension if concomitant injuries allowed 4 weeks postoperatively. The brace were removed 6 weeks later.</p><p><b>RESULTS</b>Among them, 25 patients were followed up for 6 to 24 months with an average of 15 months. The X-ray examination showed satisfactory reduction, and bony union was obtained in all the patients. The Lachman test was negative in all patients. No complications such as malunion or joint stiffness were found. The extension of affected knee was normal and its flexion were (136 +/- 12) degrees. According to Lysholm knee score system,it was preoperatively (41.80 +/- 6.16) and (94.10 +/- 8.26) six months after surgery respectively. Twenty-two cases were excellent, 2 cases good and 1 fair.</p><p><b>CONCLUSION</b>Treatment of tibial avulsion fracture of the posterior cruciate ligament with open reduction and internal fixation with wires through posteromedial inverted "L" approach is a safe, effective method, due to its stable fixation and relatively low expense. It is believed as an ideal choice for tibial avulsion fracture of the posterior cruciate ligament.</p>

Analysis of therapeutic effects of cannulated compression screws for the treatment of femoral neck fractures / 中国骨伤

<p><b>OBJECTIVE</b>To evaluate the therapeutic effects of cannulated compression screws for the treatment of femoral neck fractures, and to investigate the related factors influencing the avascular necrosis of femoral head after surgery.</p><p><b>METHODS</b>A retrospective review was done for 96 patients with femoral neck fractures treated with cannulated compression screws from January 2003 to June 2009. Among them, there were 44 males and 52 females with 21 to 88 years old (averaged 56.3 years old). According to Garden classification, 4 patients were type I, 34 patients were type II, 37 patients were type III and 21 patients were type IV. Factors such as patients' age, gender, fracture type, duration from injury to surgery and fracture reduction quality were statistically analysed to find correlations with nonunion and avascular necrosis of femoral head.</p><p><b>RESULTS</b>Eighty-four patients were followed up ranging from 9 to 60 months and the mean time was 25.4 months. Postoperative complications included deep venous thrombosis of lower extremity in 2 cases, bone nonunion in 8 cases and avascular necrosis of femoral head in 11 cases. According to Harris criterion, the total postoperative Harris score was 86.20 +/- 11.00, and 40 patients got an excellent result, 32 good, 7 fair and 5 poor. The incidence of avascular necrosis of femoral head in nondisplaced fracture group and displaced fractures group were 3.22% and 18.87% respectively;and there were significant difference between the two groups (P = 0.037). The incidence of avascular necrosis of femoral head in anatomical reduction group and non-anatomical reduction group were 5.00% and 20.45% respectively; also,significant difference was existed between the two groups (P = 0.036). However, there was no statistically significant difference of the incidence of avascular necrosis of femoral head according to different age, sex, operative time.</p><p><b>CONCLUSION</b>The therapeutic effect of cannulated compression screws for non-displaced femoral neck fractures is good. The fracture type and reduction quality are found to be main factors correlated with avascular necrosis of femoral head statistically. For young patients with a displaced femoral neck fracture,in order to avoid incidence of avascular necrosis of femoral head, anatomical reduction should be ensured. For elder patients with a severe displaced femoral neck fracture, the total hip replacement should be recommended.</p>

Biodegradable chitosan scaffolds containing microspheres as carriers for controlled transforming growth factor-beta1 delivery for cartilage tissue engineering / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Natural articular cartilage has a limited capacity for spontaneous regeneration. Controlled release of transforming growth factor-beta1 (TGF-beta1) to cartilage defects can enhance chondrogenesis. In this study, we assessed the feasibility of using biodegradable chitosan microspheres as carriers for controlled TGF-beta1 delivery and the effect of released TGF-beta1 on the chondrogenic potential of chondrocytes.</p><p><b>METHODS</b>Chitosan scaffolds and chitosan microspheres loaded with TGF-beta1 were prepared by the freeze-drying and the emulsion-crosslinking method respectively. In vitro drug release kinetics, as measured by enzyme-linked immunosorbent assay, was monitored for 7 days. Lysozyme degradation was performed for 4 weeks to detect in vitro degradability of the scaffolds and the microspheres. Rabbit chondrocytes were seeded on the scaffolds containing TGF-beta1 microspheres and incubated in vitro for 3 weeks. Histological examination and type II collagen immunohistochemical staining was performed to evaluate the effects of released TGF-beta1 on cell adhesivity, proliferation and synthesis of the extracellular matrix.</p><p><b>RESULTS</b>TGF-beta1 was encapsulated into chitosan microspheres and the encapsulation efficiency of TGF-beta1 was high (90.1%). During 4 weeks of incubation in lysozyme solution for in vitro degradation, the mass of both the scaffolds and the microspheres decreased continuously and significant morphological changes was noticed. From the release experiments, it was found that TGF-beta1 could be released from the microspheres in a multiphasic fashion including an initial burst phase, a slow linear release phase and a plateau phase. The release amount of TGF-beta1 was 37.4%, 50.7%, 61.3%, and 63.5% for 1, 3, 5, and 7 days respectively. At 21 days after cultivation, type II collagen immunohistochemical staining was performed. The mean percentage of positive cells for collagen type II in control group (32.7% +/- 10.4%) was significantly lower than that in the controlled TGF-beta1 release group (92.4% +/- 4.8%, P < 0.05). Both the proliferation rate and production of collagen type II in the transforming growth factor-beta1 microsphere incorporated scaffolds were significantly higher than those in the scaffolds without microspheres, indicating that the activity of TGF-beta1 was retained during microsphere fabrication and after growth factor release.</p><p><b>CONCLUSION</b>Chitosan microspheres can serve as delivery vehicles for controlled release of TGF-beta1, and the released growth factor can augment chondrocytes proliferation and synthesis of extracellular matrix. Chitosan scaffolds incorporated with chitosan microspheres loaded with TGF-beta1 possess a promising potential to be applied for controlled cytokine delivery and cartilage tissue engineering.</p>