Objective To investigate the development of dynamic hipscrew (DHS) internal fixation in the treatment of intertrochanteric femur fractures. Methods The latest relevant articles were reviewed extensively, including biomechanics and clinical application research. Results DHS is the effective selection for the treatment of intertrochanteric femur fractures, especially by the innovation of DHS structure, operative manipulation.Conclusion Treatment of intertrochanteric femur fractures with DHS is still a gold level, but strict selection of patients, proficiency operation and invasive manipulation are the most essential principles.
Objective To investigate the value of using Footscan system to evaluate the therapeutic effect of two internal fixation methods on calcaneus fractures. Methods From February 2006 to September 2006, 64 patients with fresh unilateral closed calcaneus fractures were randomly divided into two groups. The experimental group: 32 patients underwentminimally invasive open reduction and internal fixation with improved compressing plate and screw, including 28 males and 4 females aged 20-53 years old (average 36.7 years old); the course of disease was 3-14 days; there were 19 cases of type II, 11 of type III, and 2 of type IV according to Sanders fracture classification system. The control group: 32 patients underwent internal fixation of standard AO plate via L-shaped incision, including 29 males and 3 females aged 18-56 years old (average 37.1 years old); the course of disease was 4-15 days; there were 18 cases of type II, 11 of type III and 23 of type IV according to Sanders fracture classification system. No significant difference was noted between two groups in the general information (P gt; 0.05). At 1 and 2 years after operation, dynamic plantar pressure was measured using Footscan system, Maryland foot scores of two groups was compared, and statistical analysis was performed. Results All patients were followed up for 2 years. No infection, cuticular border necrosis, and sural nerve distal end injury occurred in the experimental group, whereas in the control group, 3 patients suffered from cuticular border necrosis and recovered after dressing, and 1 patient had sural nerve distal end injury with decreased sensation in local skin. At 1 and 2 years after operation, in the control group, there were significant differences between the injured foot and the normal foot in terms of impulse, instep index, motion range of subtalar joint, lateral displacement of footplate pressure center, and calcaneal width when patients stood on both feet (P lt; 0.05), whereas in the experimental group, no significant differences were noted between the injured foot and the normal foot in terms of the above parameters (P gt; 0.05). Significant differences were noted between two groups in terms of the above parameters (P lt; 0.05). The Maryland score 1 yearafter operation was (86.74 ± 8.56) points for the experimental group and (71.24 ± 10.06) points for the control group; at 2 years after operation, it was increased to (87.35 ± 8.49) points and (72.41 ± 9.69) points, respectively, indicating there was a significant difference between two groups (P lt; 0.05). Conclusion Operative outcomes of internal fixation with improved compressing plate are superior to those of standard AO plate. Footscan system can provide a quantitative assessment on the operative effect of calcaneus fractures.
Objective Targeted adenoviral gene delivery from peripheral nerves was used to integrally analyse the characterization and time course of LacZ gene (AdLacZ) retrograde transfer to spinal cord and transgene product anterograde labeling ofperipheral nerve. Methods Recombinant replication-defective adenovirus containing AdLacZ was administrated to the cut proximal stumps of median and tibial nerves in Wister rats. Then the transected nerve was repaired with 10-0 nylon sutures. At different time point postinfection the spinal cords of C5 to T1 attached with DRGs and brachial plexuses, or L2 to L6 attached with DRGs and lumbosacralplexuses were removed. The removed spinal cord and DRGs were cut into 50 μm serialcoronal sections and processed for X-gal staining and immunohistochemical staining. The whole specimens of brachial or lumbosacral plexuses attaching with theirperipheral nerves were processed for X-gal staining. The number of X-gal stained neurons was counted and the initial detected time of retrograde labeling, peaktime and persisting period of gene expression in DRG sensory neurons, spinal cord motor neurons and peripheral nerves were studied. Results The gene transfer was specifically targeted to the particular segments of spinal cord andDRGs, and transgene expression was strictly unilaterally corresponding to the infected nerves. Within the same nerve models, the initial detected time of gene expression was earliest in DRG neurons, then in the motor neurons and latest in peripheral nerves. The persisting duration of β-gal staining was shortest in motor neurons, then in sensory neurons and longest in peripheral nerves. The initial detected time of β-gal staining in median nerve models was earlier in mediannerve models compared with that in the tibial nerve models. Although the initial detected time and the beginning of peak duration of β-gal staining were not same, the decreasing time of β-gal staining in motor and sensory neurons of thetwo nerve models were started at about the same day 8 post-infection. The labeled neurons were more in tibial nerve-models than that in median nerve models. Within the same models, the labeled sensory neurons of DRGs were morethan labeled motor neurons of ventral horn. The β-gal staining was tenser in median nerves than that in tibial nerves. However the persisting time of β-gal staining was longer in tibial nerve models. Conclusion The b gene expression in neurons and PNS renders this system particularly attractive for neuroanatomical tracing studies. Furthermore this gene delivery method allowing specific targeting of motor and sensory neurons without damaging the spinal cord might offer potentialities for the gene therapy of peripheral nerve injury.
OBJECTIVE To investigate the effects of targeted muscular injection of ciliary neurotrophic factor (CNTF) on the regeneration of injured peripheral nerves. METHODS The left sciatic nerves of 80 Sprague-Dawley rats were excised to form 6 mm defect and the two ends were bridged by silicone tubes, they were randomly divided into two groups, CNTF group and normal saline (NS) group. The CNTF group was given recombinant human CNTF, 1 mg/kg every other day for 30 days, and the NS group was given equal quantity of normal saline as NS group. The sciatic nerve functional index (SFI), electrophysiological assessment, morphometric analysis of axons, and choleratoxin horseradish peroxidase (CB-HRP) retrograde-labelling were measured postoperatively. RESULTS The SFI, electrophysiological parameters (nerve conduction velocity, latency and amplitude of compound muscle action potentials), myelinated axons counts, mean axons diameters and myelin sheath thickness, number of CB-HRP labelled ventral horn motor neurons of spinal cord were significantly higher in CNTF group than that of NS group. CONCLUSION Targeted muscular injection of CNTF can promote the regeneration of peripheral nerve and improve the nerve functional recovery.
Objective To review the biomechanical research progress of internal fixation of tibial plateau fracture in recent years and provide a reference for the selection of internal fixation in clinic. Methods The literature related to the biomechanical research of internal fixation of tibial plateau fracture at home and abroad was extensively reviewed, and the biomechanical characteristics of the internal fixation mode and position as well as the biomechanical characteristics of different internal fixators, such as screws, plates, and intramedullary nails were summarized and analyzed. Results Tibial plateau fracture is one of the common types of knee fractures. The conventional surgical treatment for tibial plateau fracture is open or closed reduction and internal fixation, which requires anatomical reduction and strong fixation. Anatomical reduction can restore the normal shape of the knee joint; strong fixation provides good biomechanical stability, so that the patient can have early functional exercise, restore knee mobility as early as possible, and avoid knee stiffness. Different internal fixators have their own biomechanical strengths and characteristics. The screw fixation has the advantage of being minimally invasive, but the fixation strength is limited, and it is mostly applied to Schatzker typeⅠfracture. For Schatzker Ⅰ-Ⅳ fracture, unilateral plate fixation can be used; for Schatzker Ⅴand Ⅵ fracture, bilateral plates fixation can be used to provide stronger fixation strength and avoid the stress concentration. The intramedullary nails fixation has the advantages of less trauma and less influence on the blood flow of the fracture end, but the fixation strength of the medial and lateral plateau is limited; so it is more suitable for tibial plateau fracture that involves only the metaphysis. Choosing the most appropriate internal fixation according to the patient’s condition is still a major difficulty in the surgical treatment of tibial plateau fractures. Conclusion Each internal fixator has good fixation effect on tibial plateau fracture within the applicable range, and it is an important research direction to improve and innovate the existing internal fixator from various aspects, such as manufacturing process, material, and morphology.
Objective To explore the occurrence condition of the neck axial symptom (AS) after cervical Bryan artificial disc replacement combined with anterior cervical discectomy and fusion (Hybrid surgery) and traditional anterior cervical discectomy and fusion (ACDF surgery) to treat the two-level cervical disease, and to do contrastive analysis. Methods Between August 2006 and March 2010, 18 patients underwent Hybrid surgery (group A) and 30 patients underwent two-level ACDF surgery (group B). There was no significant difference in age, gender, disease duration, type, and operated segment between 2 groups (P gt; 0.05). The Japanese Orthopaedic Association (JOA) score, neck disability index (NDI) score, cervical curvature of the operated segment, total range of motion (ROM) of C2-7, ROM of the adjacent segment, and incidence of neck AS were recorded and compared between before operation and at last follow-up. Results All the patients were followed up 18-34 months (24.1 months on average). In both groups, the JOA and NDI scores at last follow-up had significantly improvement when compared with preoperative scores (P lt; 0.01), but there was no significant difference between 2 groups at preoperation and last follow-up (P gt; 0.05). The kyphosis incidence of the operated segment in group B was significantly higher than that in group A (χ2=5.333, P=0.021). There was no significant difference in the total ROM of C2-7 between at preoperation and last follow-up in group A (t=0.410, P=0.685); the total ROM of C2-7 at last follow-up was significantly lower than that at preoperation in group B (t=3.007, P=0.006); and significant difference was found between 2 groups at last follow-up (t=2.664, P=0.013). At last follow-up, ROM of the superior and inferior adjacent segments in group B increased obviously (P lt; 0.05) and was significantly higher than that in group A (t=2.252, P=0.033; t=2.203, P=0.037). The incidence of neck AS were 16.7% in group A and 46.7% in group B, showing significant difference at last follow-up (χ2=4.427, P=0.035). Conclusion Compared with two-level ACDF surgery, Hybrid surgery has good outcomes. At the same time, it can maintain the curvature of operated segments and total ROM, avoid excessive increased ROM of the adjacent segments, and reduce the incidence of neck AS.
To explore a new approach to treat old scaphoid fracture by grafting bones from distal radius and fixing absorbable screws. Methods From January 2002 to May 2007, 18 patients with old scaphoid fractures were treated by grafting bones from distal radius and fixing absorbable screws. All of the 18 patients (13 males and 5 females, aged from 17 to 41 years old) had the injury history of the palm of hand touching the ground. They felt tenderness on the anatomical snuff-box and tubercle of scaphoid bone. The grasping force decreased. The range of motion of the wrist was (36 ± 2)° extension/(30 ± 3)° flexion, (8 ± 3)° radial is/(13 ± 2)° ulnaris. Results The average postoperative follow-up period was 15.7 months．A total of 18 cases achieved bone union. The range of motion of the wrist in the 16 healed cases was (68 ± 2)° extension/(65 ± 3)° flexion, (15 ± 3)° radial is/(28 ± 5)° ulnaris. There was no pain of motion and symptom of powerlessness. As to the other 2 cases, the range of motion of the wrist was (40 ± 8)° extension/(35 ± 6)° flexion, (8 ± 5)° radial is/(12 ± 5)° ulnaris; no obvious improvement was found; the patients occasionally felt painful in daily l ife; the extension force decreased. No infection and break of internal fixation were seen. Conclusion The absorbable screw as a new biomaterial for internal fixation has obvious advantages of good biocompatibil ity, promoting union of the fracture and no need of a second operation for removal．
ObjectiveTo evaluate the effectiveness of the leverage reduction with proximal femoral nail antirotation (PFNA) ball head screw driver for difficult-reducing intertrochanteric fracture.MethodsThe clinical data of 8 patients with difficult-reducing intertrochanteric fractures between July 2015 and February 2018 were retrospectively analysed. There were 3 males and 5 females, aged 66-89 years, with an average age of 76.3 years. According to Evans classification, there were 3 cases of type Ⅲ and 5 cases of type Ⅳ. The time from injury to operation was 2-8 days (mean, 3.9 days). All patients were reducted with ball head screw driver leverage through PFNA proximal incision during operation. The operation time, intraoperative blood loss, reduction time, and fluoroscopy times were recorded. Harris hip function score was used to evaluate the effectiveness at last follow-up.ResultsThe operation time was 52.5-83.7 minutes (mean, 68.1 minutes), the intraoperative blood loss was 49.8-96.4 mL (mean, 73.1 mL), the reduction time was 3.7-9.1 minutes (mean, 6.4 minutes), and the fluoroscopy times were 18.4-27.4 times (mean, 22.9 times). Patients were followed up 6-18 months (mean, 9.6 months). Postoperative X-ray films showed that the fracture obtained good reduction. No fracture displacement, fixation failure, and coxa vara occurred after operation. Fracture healing time was 3-6 months (mean, 4.6 months). At last follow-up, the Harris hip function score was 85-96 (mean, 91.6), with a result of excellent in 6 cases and good in 2 cases.ConclusionThe reduction of difficult-reducing intertrochanteric fracture by using ball head screw driver can obtain good reduction and reliable fixation. The method has such advantages as no more incision, and less blood loss and soft tissue injury.
Objective Tri ptol ide can suppress immunological rejection reaction. To investigate the effect of tri ptol ide on allogenic tendon transplantation in repairing tendon defect in chicken. Methods The defect model of the third toes tendon was establ ished in 64 healthy-cleaning male Leghorn chickens (4-month-old, weighing 1.9-2.3 kg), which underwent allogenic tendon transplantation for repairing and were divided into 2 groups randomly (n=32). Tri ptol ide feeding[100 μg/(kg·d)] was given for 3 weeks in the experimental group and normal feeding in the control group. General condition of the chickens was observed after operation. The transplanted tendons were harvested from 4 chickens in each group for gross observation at 1, 2, 3, and 4 weeks after operation; the histological observation was performed at 1 and 3 weeks, and transmission electron microscope observation at 2 and 4 weeks. The blood and tendon were harvested from another 8 chickens in each group for flow cytometry and biomechanical tests respectively at 3 and 6 weeks. Results All chickens survived to the experiment end. Gross observation: with time extending, hyperemia and edema around transplanted tendon were rel ieved. Rarefaction adhering zone was seen in experimental group, and pyknotic adhering zone in control group. Histological observation: inflammatory reaction in experimental group was sl ighter than that in control group at 1 and 3 weeks. Transmission electron microscope observation: at 2 and 4 weeks, fibroblasts had big cell nucleus, more euchromatin, and l ittle heterochromatin in experimental group; however, there were small amount of rough endocytoplasmic reticulums with gentle expanded capsular space in control group, which contained sparse content. Flow cytometry test: at 3 and 6 weeks, peri pheral blood contained less CD4+ and CD8+ T lymphocytes in experimental group than in control group, and the ratio of CD4+ to CD8+ T lymphocyte significantly decreased in experimental group when compared with control group (P lt; 0.05). Biomechanical examination: at 3and 6 weeks, the maximum tensile strength in experimental group was bigger than that in control group, and tensile adhesion power in experimental group was smaller than that in control group. There were significant differences in the indexes between 2 groups (P lt; 0.05). Conclusion Tri ptol ide can suppress immunological rejection reaction, strengthen tendon healing strength, and reduce tendon adhesion in allogenic tendon transplantation.
Objective To evaluate the effects of in situ subtalar arthrodesis with bone graft for subtalar traumatic arthritis, and to analyse the plantar pressure distribution so as to provide the evidence for effectiveness evaluation. Methods Between March 2004 and December 2008, 26 patients with unilateral subtalar arthrodesis undergoing bone graft fusion wereenrolled (test group). After operation, the imageology diversity and the effect of subtalar arthrodesis on adjacent joint wereobserved. American Orthopaedic Foot and Ankel Society (AOFAS) ankle and hindfoot score and radiographs were used to assess the foot function before and after operation. Twenty-six normal subjects served as controls. Footscan system was used to test the distribution of maximum plantar pressure and the change of gravity center curve. No significant difference was found in gender, age, height, and weight between 2 groups (P gt; 0.05). Results All patients were followed up 18.2 months on average (range, 14-71 months). The mean subtalar arthrodesis time was 5.6 months (range, 4 months and 15 days to 11 months). The mean AOFAS ankle and hindfoot score improved from 35.18 ± 8.16 preoperatively to 76.36 ± 6.90 postoperatively (t=13.910, P=0.000). Nine (34.6%) patients had satisfactory functional effects, and 13 (50.0%) patients basically satisfactory. The talocalcaneal height, talocalcaneal angle, talar decl ination angle, and calcaneus patch angle were 87.04% ± 6.17%, 76.73% ± 5.13%, 65.86% ± 7.01%, and 70.19% ± 8.33% of the contralateral side, respectively. Osteoarthritis of the adjacent joints occurred in 7 cases. The maximum plantar pressure increased in the third to fifth metatarsal bones and decreased in the first to second metatarsal bones, showing significant differences when compared with normal controls (P lt; 0.05). No significant difference was found in the plantar pressure between arthrodesis foot and contralateral foot of the test group (P gt; 0.05). The plantar pressure was well distributed in patient who was satisfied with the effect, but it was still different from normal controls. In patients who had high plantar pressure n middle foot, mild heel inversion occurred. The gravity center curve of the contralateral foot in the test group was almost the same as that of normal controls; curve medially shifted when forefoot touched down. The curve irregularly and laterally shifted in the subtalar arthrodesis foot; the curve did not medially shift when forefoot touched down. Conclusion In situ subtalar arthrodesis with bone graft has good cl inical results for subtalar traumatic arthritis. Gait analysis can be appl ied to assess the therapeutic effectiveness, and contribute to make a surgical plan. For the adaptive alteration of contralateral side after subtalar arthrodesis, a cohort of normal subjects should be used for comparison in gait analysis.