Systemic administration with melatonin in the daytime has a better effect on promoting osseointegration of titanium rods in ovariectomized rats.

AIMS: This study examined whether systemic administration of melatonin would have different effects on osseointegration in ovariectomized (OVX) rats, depending on whether this was administered during the day or night. METHODS: In this study, a titanium rod was implanted in the medullary cavity of one femoral metaphysis in OVX rats, and then the rats were randomly divided into four groups: Sham group (Sham, n = 10), OVX rat group (OVX, n = 10), melatonin day treatment group (OVX + MD, n = 10), and melatonin night treatment group (OVX + MN, n = 10). The OVX + MD and OVX + MN rats were treated with 30 mg/kg/day melatonin at 9 am and 9 pm, respectively, for 12 weeks. At the end of the research, the rats were killed to obtain bilateral femora and blood samples for evaluation. RESULTS: Micro-CT and histological evaluation showed that the bone microscopic parameters of femoral metaphysis trabecular bone and bone tissue around the titanium rod in the OVX + MD group demonstrated higher bone mineral density, bone volume fraction, trabecular number, connective density, trabecular thickness, and lower trabecular speculation (p = 0.004) than the OVX + MN group. Moreover, the biomechanical parameters of the OVX + MD group showed higher pull-out test and three-point bending test values, including fixation strength, interface stiffness, energy to failure, energy at break, ultimate load, and elastic modulus (p = 0.012) than the OVX + MN group. In addition, the bone metabolism index and oxidative stress indicators of the OVX + MD group show lower values of Type I collagen cross-linked C-telopeptide, procollagen type 1 N propeptide, and malondialdehyde (p = 0.013), and higher values of TAC and SOD (p = 0.002) compared with the OVX + MN group. CONCLUSION: The results of our study suggest that systemic administration with melatonin at 9 am may improve the initial osseointegration of titanium rods under osteoporotic conditions more effectively than administration at 9 pm.Cite this article: Bone Joint Res 2022;11(11):751-762.

[Imageology study of correlation loss and its related factors after short-segment pedicle screw reduction and fixation for lumbar fractures].

OBJECTIVE: To analyze the correction loss after posterior segmental fixation for lumbar spine fractures and explore the related image factors. METHODS: Posterior short-segment fixation was received in 48 patients with L2-L4 fractures. There were 32 males and 16 females, with ages of 23 to 60 (45.98±8.20) yeaes. The anterior vertebrae height (AVH), vertebral wedge angle (VWA) of the injured vertebra and local kyphosis angle (LKA) were measured before operation, 1 week after operation and the final follow-up. The loss of segmental discal angle (LoSDA), LKA(LoLKA), AVH(LoAVH) were calculated between 1 week postoperative and the last follow up. Preoperative load-sharing scores(LSS), TLICS scores, and adjacent intervertebral disc injuries (IDIs) were assessed. Then the correlation between the age, follow up time, LSS, TLICS, IDIs and the correction loss was analyzed. RESULTS: The average follow-up was 12 to 18 (16.13±5.39) months. LKA, AVH and VWA at 1 week postoperative and those at the final follow up, were significantly improved compared with those preoperative (P<0.05). In the final follow up, the average LKA(5.70±3.17)° and AVH(4.31±5.95)% correction loss were observed compared with those 1 week postoperative(P<0.05). Otherwise the lose of VWA was not obvious(P>0.05). Univariate analysis showed that the SDA (r=0.706, 0.579, 0.449) and LKA(r=0.715, 0.566, 0.502) correction loss were aggravated with the increase of LSS, TLICS and IDIs, and AVH (r=-0.325, -0.219) correction loss was aggravated with the increase of LSS and TLICS(P<0.05). Multivariate analysis showed that increased LSS scores were all risk factors for segmental disc angle (SDA) loss, LKA correction loss, and AVH correction loss (P<0.05). CONCLUSION: The angle of adjacent intervertebral discs and anterior height of injured vertebrae were lost statistically after posterior short-segment pedicle screw treatment for lumbar fractures, and multivariate analysis showed that all of them were correlated with load-sharing score.

[Minimally invasive percutaneous plate internal fixation through anterolateral single incision for the treatment of open distal tibiofibula fractures].

OBJECTIVE: To investigate therapeutic effect of minimally invasive percutaneous plate internal fixation (MIPPO) through a single incision in treating open distal tibiofibula fractures. METHODS: From March 2015 to February 2019, 10 patients with open distal tibiofibula fractures were treated with MIPPO technique through single anterolateral incision, including 8 males and 2 females, aged from 31 to 68 years old. According to Gustilo classification, 6 patients were typeⅠ, 3 patients were typeⅡand 1 patient was type ⅢA. Operative time, intraoperative blood loss and fracture healing were observed, Mazur ankle joint scoring was used to evaluate clinical effect. RESULTS: All patients were followed up from 9 to 24 months. Operative time ranged from 85 to 120 min, intraoperative blood loss ranged from 80 to 200 ml, fracture healing time ranged from 18 to 30 weeks. Nine patients with Gustilo typeⅠandⅡachieved satisfactory healing wound, original wound of 1 patient with Gustilo type ⅢA was poor, and healed by skin flap transplantation at stageⅡ. No steel exposed and infection occurred. According to Mazur ankle scoring at the final following-up, total score was from 61 to 97, and 8 patients got excellent result, 1 good and 1 poor. CONCLUSION: MIPPO technique through anterolateral single incision for the treatment of open distal tibiofibula fractures could protect original medial wound in opertaion, avoid plate exposed through anterolateral extensor tendon to cover internal fixation, and MIPPO technique could protect fracture end blood flow to improve fracture healing rate, and it is a kind of choice.

[Repair of the fracture of the joint of tendon and bone of the quadriceps femoris tendon with wire anchor and transverse drilling of the patella].

OBJECTIVE: To explore the effect of suture anchor combined with transverse drilling of patella to repair the fracture of the joint of bone and tendon of quadriceps femoris tendon. METHODS: From April 2016 to January 2018, 6 patients (8 knees) with complete rupture of the joint of the tendon and bone tendon of the quadriceps femoris were treated with the combination of anchor with wire and transverse drilling of the patella, including 5 males (7 knees) and 1 female, aged from 43 to 74 years with an average age of 53 years old. All the patients had pain in knee joint and could not extend the knee actively after trauma. X-ray, CT and MRI were performed on the knee joints, and it was clear that the joint of bone and tendon of quadriceps femoris tendon was completely broken. The X-ray of knee joint was reviewed regularly after operation, and Lysholm score was used to evaluate the function of knee joint. RESULTS: The average operation time of all patients was 60 minutes. Tourniquets were used during the operation, no drainage was placed after the operation, and no blood transfusion was performed in all patients. Six patients were followed up for 15 to 36 months with an average of 26 months. Lysholm score of 6 patients (8 knees) was 79 to 95 in the last follow-up with an average of 89 points. One of the patients with mandatory spondylitis developed infection and healed after 2 debridements. CONCLUSION: The suture structure of the joint of bone and tendon of quadriceps femoris tendon repaired with suture anchor and lateral drilling of patella is simple, reliable and effective.

[Analysis of the clinical effects of different pedicle screw fixation methods for the treatment of thoracolumbar fractures].

OBJECTIVE: To discuss the clinical effects of the different pedicle screw fixation methods for the treatment of thoracolumbar fractures. METHODS: The clinical data of 55 patients with single thoracolumbar fractures treated between January 2013 and December 2016 were retrospectively analyzed. There were 32 males and 23 females, aged from 20 to 55 years with an average of 35.6 years old. All the fractures were located on a single segment, 8 cases of T11, 18 cases of T12, 19 cases of L1, 10 cases of L2. According to the classification of AO, 10 cases were type A1, 17 cases were type A2, 18 cases were type A3, 7 cases were type B2, 2 cases were type B3, 1 case was type C1. The patients were divided into three groups according to the different fixation methods, among them, 20 cases treated by traditional short-segment 4 pedicle screws fixation were control group, 22 cases treated by intermediate bilateral pedicle screws fixation (6 pedicle screws fixation) were bilateral group, 13 cases treated by intermediate unilateral pedicle screw fixation (5 pedicle screws fixation) were unilateral group. The three groups were compared by operation time, intraoperative blood loss, hospitalization cost, VAS and ODI scores, the correction of the fractured vertebrae height and kyphosis angle postoperatively and the losing rate of the fractured vertebrae height and kyphosis angle at the final follow-up and so on. RESULTS: All the patients were followed up from 12 to 20 months with an average of 15.2 months. No complications such as loosening of internal fixation and breakage were found after operation. There was no significant difference in operation time and intraoperative blood loss among three groups(P>0.05). In terms of hospitalization cost, the control group[(20 932.4±298.3)yuan] was significantly lower than the unilateral group[(22 428.2±321.5)yuan] and the bilateral group [(23 630.5±310.5)yuan] (P<0.05), and the unilateral group was lower than the bilateral group (P<0.05). There was no significant difference in VAS and ODI scores at preoperative, postoperative 1 week and final follow-up among the groups(P>0.05). And there was no significant difference in the correction of the injuried vertebrae height and kyphosis angle immediately after operation among three groups(P>0.05). However, for the losing rate of the injuried vertebrae height at the final follow-up, the unilateral group[(6.3±2.1)%] and bilateral group [(5.6±2.8)%] were significantly better than the control group[(9.2±1.8)%] (P<0.05), there was no significant difference between unilateral group and bilateral group; for the losing rate of kyphosis angle at the final follow-up, the unilateral group[(15.2±6.5)%] and bilateral group[(13.9±7.2)%] were significantly better than the control group[(23.6±7.5)%] (P<0.05), but there was no statistical difference between the unilateral and bilateral group(P>0.05). CONCLUSIONS: All the three different pedicle screw fixation methods are suitable for the treatment of thoracolumbar fractures and the short-term clinical effects are consistent. Compared with traditional short-segment 4 pedicle screws fixation, intermediate bilateral or unilateral pedicle screw fixation were more effective in maintaining the height of the injuried vertebrae and preventing the occurrence of kyphosis. The intermediate unilateral pedicle screw fixation was comparable to that of bilateral fixation at clinical outcomes, but the unilateral fixed hospitalization cost was lower, which was worthy of clinical promotion.

[Quality control of clinical data management based on EDC].

With the wide application of electronic data management (EDC), the data management is shifting to a new mode. In order to recognize the advantages of EDC, we choose 20 representative registered clinical trials, which involve 5 404 subjects and 321 sites. We found that EDC has many beneficial impacts on the course of clinical trial data management, including the process of data collection, data cleaning, data quality control and clinical trial decision-making. The result also provides a reference for the adoption of EDC in clinical trials.

[Posterior short-segment fixation with undermining decompress for upper lumbar burst fractures].

OBJECTIVE: To observe clinical effects of posterior short-segment fixation with undermining decompress by posterior ligament complex for the treatment of upper lumbar burst fractures. METHODS: From October 2010 to March 2013,23 patients with upper lumbar burst fractures (Denis B type) were treated by posterior short-segment fixation with undermining decompress by posterior ligament complex. There were 18 males and 5 females aged from 26 to 64 years old with an average of 45.7 years old. Twelve patients were caused by falling down, 5 cases were caused by traffic accident, 4 cases were the bruise injury caused by heavy object and 2 cases were caused by other injury. Fourteen patients were L1 fracture and 9 patients were L2 fracture. Thirteen patients were combined with nerve injuries (degree D according to ASIA classification). Internal fixation were removed from 12 to 20 months with an average of 14.3 months. JOA scores and imaging changes were recorded and compared at different time points. RESULTS: All patients were followed up from 18 to 24 months with an average of 20.4 months. Thirteen patients with nerve injuries were completely recovered at 3 to 6 months after operation. JOA score at 1 year after operation was 20.63 ± 0.92, and 20.38 ± 1.06 at 3 months after removal of internal fixation,which were improved obviously than 9.90 ± 2.73 at 3 months after operation. (P > 0.05) Anterior height of injured vertebrae, vertebral body angle and local Cobb angle was (95.0 ± 0.53)%, (2.78 ± 1.36) and (2.43 ± 1.52) °respectively, and improved obviously than that of before operation (P < 0.05). There was no statistical significance in JOA scores at 3 months after removal of internal fixation and 1 year after operation (P > 0.05). CONCLUSION: posterior short-segment fixation with undermining decompress by posterior ligament complex for the treatment of upper lumbar burst fractures has advantages of minimally invasive, could effective recover vertebrae height, maintain stability of spine, decrease low back pain. It is a safe and effective operative method.