Objective To study the effect of local appl ication of different concentrations of nerve growth factor (NGF) on fracture heal ing, and to further search for the appropriate concentration gradient of NGF to promote fracture heal ing. Methods Seventy-five adult male Sprague Dawley rats, weighing (220.0 ± 2.5) g, were made the right tibia fracture model at 1 cm distal from the tibial tubercle and randomly divided into 5 groups (groups A, B, C, D, and E, n=15). Fractures were treated with 0.3 mL normal sal ine containing different concentration of NGF (0.006 48 × 10-2, 0.032 40 × 10-2, 0.162 00 ×10-2, and 0.810 00 × 10-2 μg/g) in groups A, B, C, and D, respectively, and the same amount of normal sal ine in group E. After2, 4, and 6 weeks, the specimens were harvested from 5 rats of each group to perform the biochemical test and histological observation. Before the rats were sacrificed, the arteriovenous blood was taken from the eye-ball to test the alkal ine phosphatase (ALP) activity. Results After 2, 4, and 6 weeks, the gross observation showed that the size and hardness of bone tissue and callus tissue growth gradually increased in groups A, B, C, and D, and group D was higher than groups A, B, C, and E. The X-ray films showed that the calcified area gradually increased in groups A, B, C, and D, and group D was higher than groups A, B, C, and E. The histological observation showed that the trabecular qual ity and maturity in group D were better than those in groups A, B, C, and E. Group D was significantly higher than groups A, B, C, and E (P lt; 0.05) in the gray values of callus tissue and the calcium content of callus tissue at 4 and 6 weeks, in the wet weight of callus tissue at 2 and 4 weeks, and in the ALP content of serum at 2 weeks. The trabecula surface index of osteoblast, the trabecular volume, and the trabecular width decreased as time in the order of groups A, B, C, and D, which were higher than those of group E; group D was the highest, showing significant differences when compared with the other groups (P lt; 0.05). Conclusion The local appl ication of NGF can promote fracture heal ing in rats. The high concentration gradient of NGF (0.810 00 × 10-2 μg/g) has an obvious promotion role on fracture heal ing.
Objective To investigate the effect of NGF on fracture heal ing, and to study the role of BMP-2 induced osteoblast. Methods Sixty cleaned male Kunming mice (aging 6-8 weeks and weighing 23-25 g) were made fracture models in the middle of femoral shaft and randomly divided into four groups (groups A, B, C and D, n=15). Fracture was treated with NGF/ normal sal ine, BMP-2, BMP-2 /NGF/normal sal ine, and normal sal ine in groups A, B, C and D, respectively. After 14, 21 and 28 days, the specimens were selected from 5 mice each group to do the biochemical and histological analysis. Beforethe mice were killed, the arteriovenous blood was taken from their eye-ball to test the ALP activity. Results After 14 days,21 days and 28 days, the gross observation showed that the size and hardness of bone tissue, and callus tissue growth increased in groups A, B and C order and were higher than those in group D; the X-ray films showed that the calcified area increased in groups A, B and C order and were higher than those in group D; the histological observation showed that the trabecular maturity increased in groups A, B and C order and were higher than those in group D. The osteoblast area, the gray degree value of the radiographs in callus tissue, the ALP contents of serum and callus tissue, calcium content of callus tissue and net weight of callus were higher in groups A, B and C than in group D. There were significant differences (P lt; 0.05) in osteoblast area and gray degree values of the radiographs at 14, 21 and 28 days; in ALP contents of serum at 14 days; in ALP contents of callus tissue at 14 days and 21 days; in calcium content of callus tissue at 21 days and 28 days among 4 groups. There were significant differences in net weight of callus between groups B, C and groups A, D at 14 days (P lt; 0.05). At 21 days and 28 days, the trabecular surface index of osteoblast, the average trabecular volume and the mean trabecular width decreased as time went on, having an increase order of groups A, B, C and was higher in groups A, B, C than in group D, showing significant differences among 4 groups (P lt; 0.05). Conclusion NGF promotes the heal ing of fractures. NGF possesses synergistic effect on ectopic bone formation induced by BMP-2.
Objective To evaluate the effectiveness and safety of external fixation (EF) and open reduction and internal fixation (ORIF) for unstable distal radius fractures in adults. Methods We searched MEDLINE (1966 to September 2008), Cochrane Central register of controlled Trials (The Cochrane Library, Issue 3, 2008), EMbase (1974 to September 2008), CBM, CNKI, and collected randomized controlled trials (RCTs) of EF and ORIF for unstable distal radius fractures in adults. The quality of the included studies was critically assessed and data analyses were performed with the Cochrane Collaboration’s RevMan 5.0 software. Results Seven RCTs involving 634 patients were included, of which 269 were in EF group, and 293 were in ORIF group. Only 1 study had relative high quality, all the others had some limitation in randomization, blinding, and allocation concealment. The results of meta-analyses showed that, 1) about the effectiveness: according to the Gartland and Werley grade standard, the ORIF group was better than the EF group with statistic difference (RR=1.50, 95%CI 1.11 to 2.03, P=0.008); because of the original studies did not offer the detailed data including pad strength, grip strength, flexion-extension, radial deviation, and ulnar deviation, we only processed a descriptive analysis; and 2) about complications: the infection rate of the pin track was higher in the EF group than that in the ORIF group with statistic difference (RR=0.24, 95%CI 0.08 to 0.76, P=0.02); but there were no differences between the two groups in reflex sympathetic dystrophy (RSD) (RR=0.88, 95%CI 0.30 to 2.56, P=0.82), extensor tendon rupture (RR=3.93, 95%CI 0.45 to 34.62, P=0.22), and compartment syndrome (RR=3.13, 95%CI 0.51 to 19.09, P=0.22). Conclusions Compared with EF, ORIF is much better based on Gartland and Werley grade standard, and causes much less infection. Because of the limited quality and quantity of the included studies, more proofs are required from more RCTs with large sample.