[Pain assessment of biological conduit small gap tubulization in rat sciatic nerve multilation model].

OBJECTIVE: To explore the pain sensation recovery discipline of 2 mm small gap biological conduit tubulization and epineurial neurorrhaphy in rat sciatic nerve multilation model. METHODS: Based on the rat sciatic nerve multilation model, 2 mm small gap biological conduit tubulization and epineurial neurorrhaphy were applied and the 50% paw withdrawal threshold was observed after 2, 4, 5, 6, 8 and 12 weeks. The data were analyzed by two-way ANOVA and chi-square criterion. RESULTS: Obvious hyperalgesia was observed in week 2 in both experimental group and control group, and 50% paw withdrawal threshold was improved significantly even to 15 g. The 50% paw withdrawal threshold began to decline week 4 and the 50% paw withdrawal threshold of small gap tubulization group was obviously lower than that of control group, which may imply that the pain sensation recovery of small gap tubulization group was earlier than that of control group. The 50% paw withdrawal threshold of small gap tubulization group began to increase to the plateau period [week 5: (12.70 ± 5.64) g; week 6: (12.20 ± 3.26) g; week 8: (12.31 ± 4.19) g; week 12: (13.95 ± 2.58) g]. The 50% paw withdrawal threshold of control group declined gradually [week 5: (10.47 ± 7.02) g; week 6: (9.42 ± 6.86) g; week 8: (8.50 ± 7.15) g; week 12: (8.06 ± 5.93) g]. The difference was statistical significant between small gap tubulization group and control group in 12th week. CONCLUSION: Compared with the traditional epineurial neurorrhaphy for peripheral nerve multilation, 2 mm small gap biological conduit tubulization can improve the 50% paw withdrawal threshold during peripheral nerve regeneration process and reduce the pain incidence.

Experimental study on the repair of tibial plateau defect.

OBJECTIVE: To evaluate the effect of autograft bone, allograft bone, calcium sulfate bone cement, and calcium phosphate bone cement on the repair of tibial plateau defect in rabbits. METHODS: We used autograft bone, allograft bone, calcium sulfate bone cement, and calcium phosphate bone cement to repair tibial plateau defect in rabbits. Gross and histologic observations, X-ray examination, and biomechanical test were conducted at 1, 2, 4, 8 weeks after operation. RESULTS: X-ray examination found that the bone density was evidently reduced in calcium sulfate group at 8 weeks after operation; there were no marked changes in other groups. The maximal load measurements showed that autograft and allograft groups were greater than calcium sulfate and calcium phosphate groups at 1 and 2 weeks after operation. However at 4 and 8 weeks after operation, no significant difference was found among the four groups. In autograft and allograft groups, there was no significant difference in biomechanical intensity at 2, 4, and 8 weeks, but it was significantly higher than that at 1 week. In calcium sulfate and calcium phosphate groups, the outcome was ranked in descending order as 1 week less than 2 week less than 4 week equal to 8 week. Histologic examination found a great amount of new bones at 8 week in both autograft and allograft groups. In calcium sulfate group, calcium sulfate was almost absorbed and there were numerous bone trabeculations. There was a large amount of unabsorbed calcium phosphate in calcium phosphate group. CONCLUSION: At 1-2 weeks postoperatively, the biomechanical intensity is higher in autograft and allograft groups than calcium sulfate and calcium phosphate groups, but after 4-8 weeks, there is no significant difference among groups. At 1-2 weeks, the biomechanical intensity in all groups is increased, but at 4-8 weeks, there is no significant increase. The rates of absorption and bone formation are quicker in calcium sulfate group than calcium phosphate group.

[Clinical effect observation of biodegradable conduit small gap tublization repairing peripheral nerve injury].

OBJECTIVE: To observe the clinical effect of biodegradable conduit small gap tublization to repair peripheral nerve injury. METHODS: In the study, 30 cases of fresh peripheral nerve injury in the upper extremities were recruited. After formally informed and obtaining the consent, the recruited patients were divided into the degradable chitin conduit tublization group (experimental group: 15 cases) and traditional epineurial neurorrhaphy group (control group: 15 cases). Their nerve functional recovery conditions were clinically observed according to the standard score methods provided by SHEN Ning-jiang and British Medical Research Council. The excellent and good rates of the overall nerve functional recovery were calculated. The electrophysiologic study was carried out after 6 months. RESULTS: Of the total 30 cases, 28 were followed up, and there were 14 cases in the degradable chitin conduit tublization group and traditional epineurial neurorrhaphy group. The operation procedure was very simple, and the mean suture time [(8.0±0.8) min] was 20% shorter than that of the traditional epineurial neurorrhaphy group [(10.0±0.6) min]. All the wounds in the degradable chitin conduit tublization group healed as expected without rejection, hypersensitive reaction or anomalous draining. Electrophysiology examination results after 6 months displayed that the sensory nerves conduction velocity recovery rate was 77.37% of the normal value, and motor nerve conduction velocity recovery rate was 70.09% in the degradable chitin conduit tublization group. The sensory nerves conduction velocity recovery rate was 61.69% of the normal value, and motor nerve conduction velocity recovery rate was 56.15% in the traditional epineurial neurorrhaphy group. The exact propability methods was applied in the comparison of sensory and motor nerve conduction velocity recovery rate, and there was no statistically significant of two groups(sensory nerve conduction velocity recovery rate P=0.678;motor nerve conduction velocity recovery rate P=0.695). The combinated functional recovery excellent and good rates after repair in the degradable chitin conduit tublization group were 78.57%, while 28.57% in the traditional epineurial neurorrhaphy group. The Fisher's exact probabilistic method was applied in the comparison of combinated functional recovery excellent and good rates, and there was statistically significant of two groups(P=0.021). CONCLUSION: The operation procedure of the degradable chitin conduit tublization is very simple and the clinical recovery effect is much better than that of the traditional epineurial neurorrhaphy. The biodegradable conduit small gap tublization methods to repair peripheral nerve injury has the possibility to substitute the traditional epineurial neurorrhaphy.

Vertebroplasty with high-viscosity cement versus conventional kyphoplasty for osteoporotic vertebral compression fractures: a meta-analysis.

BACKGROUND: To evaluate outcomes following percutaneous vertebroplasty with high viscosity cement (PVP-HVC) and percutaneous kyphoplasty (PKP) with normal-viscosity cement in patients with osteoporotic vertebral compression fractures (OVCFs). METHODS: Pertinent studies were retrieved by searching five electronic databases up to July 2021. Additional records were identified via hand-searching of related references. Risk ratio (RR) and weighted mean difference (WMD), with their 95% confidence intervals (CIs), were calculated. A trial sequential analysis (TSA) was done for cement leakage. RESULTS: Twelve studies, embracing 1050 patients with OVCFs, were included. PVP-HVC was superior to PKP with normal-viscosity cement regarding risk of cement leakage (RR: 0.67, 95% CI: 0.54-0.83, I2 : 45.1%) and operation time (WMD: -11.26, 95% CI: -14.78 to -8.34, I2 : 88.8%). However, TSA revealed that a sufficient level of evidence for leakage reduction may have yet to be reached. PKP groups had a significant decrease in Cobb's angles postoperatively (within 1 month, WMD: 2.68, 95% CI: 1.85-3.48, I2 : 0%; after 1 year, WMD: 2.68, 95% CI: 1.35-4.01, I2 : 0%). There are no significant differences between the two procedures pertaining to injected cement volume, Visual Analogue Scale (VAS), Oswestry Disability Index (ODI) and risk of adjacent vertebral fractures. CONCLUSION: PVP-HVC and PKP with normal-viscosity cement are safe and effective treatments for the management of OVCF, but the former is superior to the latter in terms of procedure time. The potential of PVP-HVC in reducing cement leaks remains to be validated by more well-designed studies.