Conductive Hydrogel Restores Electrical Conduction to Promote Neurological Recovery in a Rat Model

Spinal cord injury (SCI), caused by significant physical trauma, as well as other pathological conditions, results in electrical signaling disruption and loss of bodily functional control below the injury site. Conductive biomaterials have been considered a promising approach for treating SCI, owing to their ability to restore electrical connections between the intact spinal cord portions across the injury site. In this study, we evaluated the ability of a conductive hydrogel, poly-3-amino-4-methoxybenzoic acid-gelatin (PAMB-G), to restore electrical signaling and improve neuronal regeneration in a rat SCI model, generated using the compression clip method. Gelatin or PAMB-G was injected at the SCI site, yielding 3 groups: Control (saline), Gelatin, and PAMB-G. During the 8-week study, PAMB-G, compared to Control, had significantly lower pro-inflammatory factor expression, such as for tumor necrosis factor (TNF)-α (0.388±0.276 for PAMB-G vs. 1.027±0.431 for Control) and monocyte chemoattractant protein (MCP)-1 (0.443±0.201 for PAMB-G vs. 1.662±0.912 for Control). Additionally, PAMB-G had lower astrocyte and microglia numbers (35.75±4.349 and 40.75±7.890, respectively), compared to Control (50.75±6.5 and 64.75±10.72) and Gelatin (48.75±4.787 and 71.75±7.411). PAMB-G-treated rats also had significantly greater preservation and regeneration of remaining intact neuronal tissue (0.523±0.059% mean white matter in PAMB-G vs 0.377±0.044% in Control and 0.385±0.051% in Gelatin), owing to reduced apoptosis and increased neuronal growth-associated gene expression. All these processes stemmed from PAMB-G facilitating increased electrical signaling conduction, leading to locomotive functional improvements, in the form of increased Basso-Beattie-Bresnahan (BBB) scores and steeper angles in the slope test (76.667±5.164 for PAMB-G, vs. 59.167 ±4.916 for Control and 58.333±4.082 for Gelatin), as well as reduced gastrocnemius muscle atrophy (0.345±0.085 for PAMB-G, vs. 0.244±0.021 for Control and 0.210±0.058 for Gelatin). In conclusion, PAMB-G injection post-SCI resulted in improved electrical signaling conduction, which contributed to lowered inflammation and apoptosis, increased neuronal growth, and greater bodily functional control, suggesting its potential as a viable treatment for SCI.

Multifunctional wet-adhesive chitosan/acrylic conduit for sutureless repair of peripheral nerve injuries

The incidence of peripheral nerve injury (PNI) is high worldwide, and a poor prognosis is common. Surgical closure and repair of the affected area are crucial to ensure the effective treatment of peripheral nerve injuries. Despite being the standard treatment approach, reliance on sutures to seal the severed nerve ends introduces several limitations and restrictions. This technique is intricate and time-consuming, and the application of threading and punctate sutures may lead to tissue damage and heightened tension concentrations, thus increasing the risk of fixation failure and local inflammation. This study aimed to develop easily implantable chitosan-based peripheral nerve repair conduits that combine acrylic acid and cleavable N-hydroxysuccinimide to reduce nerve damage during repair. In ex vivo tissue adhesion tests, the conduit achieved maximal interfacial toughness of 705 J m-2 ± 30 J m-2, allowing continuous bridging of the severed nerve ends. Adhesive repair significantly reduces local inflammation caused by conventional sutures, and the positive charge of chitosan disrupts the bacterial cell wall and reduces implant-related infections. This promises to open new avenues for sutureless nerve repair and reliable medical implants.

Mimosa-Inspired Stimuli-Responsive Curling Bioadhesive Tape Promotes Peripheral Nerve Regeneration

Trauma often results in peripheral nerve injuries (PNIs). These injuries are particularly challenging therapeutically because of variable nerve diameters, slow axonal regeneration, infection of severed ends, fragility of the nerve tissue, and the intricacy of surgical intervention. Surgical suturing is likely to cause additional damage to peripheral nerves. Therefore, an ideal nerve scaffold should possess good biocompatibility, diameter adaptability, and a stable biological interface for seamless biointegration with tissues. Inspired by the curl of Mimosa pudica, this study aimed to design and develop a diameter-adaptable, suture-free, stimulated curling bioadhesive tape (SCT) hydrogel for repairing PNI. The hydrogel is fabricated from chitosan and acrylic acid-N-hydroxysuccinimide lipid via gradient crosslinking using glutaraldehyde. It closely matches the nerves of different individuals and regions, thereby providing a bionic scaffold for axonal regeneration. In addition, this hydrogel rapidly absorbs tissue fluid from the nerve surface achieving durable wet-interface adhesion. Furthermore, the chitosan-based SCT hydrogel loaded with insulin-like growth factor-I effectively promotes peripheral nerve regeneration with excellent bioactivity. This procedure for peripheral nerve injury repair using the SCT hydrogel is simple and reduces the difficulty and duration of surgery, thereby advancing adaptive biointerfaces and reliable materials for nerve repair.

A new flavonoid from Epimedium brevicornu Maxim

Epimedium brevicornu Maxim (E. brevicornu) is a plant of Epimedium L. in Berberidaceae, which is widely distributed and has high medicinal value and many important clinical applications. In this experiment, a novel flavonoid compound (1) was isolated and identified the chemical structure from E. brevicornu. The extract of E. brevicornu was performed on normal silica column chromatography, ODS silica column chromatography, Sephadex LH-20 column chromatography and RP-HPLC system to be isolated and purified and obtained 1. The HR-ESI-MS and NMR spectrometer were used to measure the accuracy molecular weights and determine the chemical structure of 1. In conclusion, we isolated and purified compound 1 (15.4 mg) and determined its chemical structure.

Respiratory Function Tolerance of Rats with Vaying Degrees of Thoracic Volume Reduction

OBJECTIVE

To compare the effects of respiratory function on different degrees of reduced thoracic volume and evaluate the tolerance of rats with reduced thoracic volume, and to assess the feasibility of thoracic volume as a measure of the severity of rib fractures.

METHODS

A total of 24 10-week-old female Sprague-Dawley (SD) rats were randomly divided into four groups (n = 6 in each group) according to the displacement degree of bilateral rib fractures (2, 4, 6, and 8 mm). The respiratory function of the rats（Tidal volume, Inspiration time, Expiration time, Breath rate, Minute volume, Peak inspiration flow) measured via whole-body barometric plethysmography before and after operation for 14 consecutive days. Respiratory function parameters of each group were analyzed. Chest CT scans were performed before and 14 days after operation, after that we reconstructed three-dimensional of the thoracic and lung and measured their volumes by computer software. We calculated the percentage of thoracic and lung volume reduction after operation.

RESULTS

At the 14th day after the operation, the decline of thoracic volume rates of in the 2, 4, 6, and 8 mm groups were 5.20%, 9.01%, 16.67%, and 20.74%, respectively. The 8 mm group showed a significant reduction in lung volume. The postoperative tidal volumes were lower in each of the groups than the baseline values before the operation. The tidal volume of the 2 mm group gradually recovered after the operation and returned to a normal level (1.54 ± 0.07 mL) at 14th day after the operation. The tidal volume of the 4, 6, and 8 mm groups recovered gradually after the operation, but did not return to baseline level at the 14th day. In particular, the tidal volume of the 8 mm group was significantly lower than that of the other groups during the 14 days (1.23 ± 0.12 mL, p < 0.05). There were no significant changes in the inspiratory and expiratory times, peak inspiratory and expiratory flows, respiratory rate, and minute ventilation during the 14 days after the operation in each group.

CONCLUSIONS

Displaced rib fractures lead to thoracic collapse and reduced thoracic volume, which can affect tidal volume in rats. The greater the decrease of thoracic volume, the more obvious the decrease of early tidal volume. The thoracic volume can be used as an objective parameter to evaluate the severity of multiple rib fractures. Early operation to restore thoracic volume may improve early respiratory function. Decreased thoracic volume affected respiratory function and can be compensated and recovered in the long term.

[Current situation and development of Chinese trauma care system]

Trauma has always been a global public health issue and urgently needed to be solved. It has great practical significance for the research of trauma care system. There are two mainstream models of trauma care system in the world. One is the prehospital care represented by the United States and the United Kingdom, which emphasizes rapid transport, and the other is the prehospital care represented by France and Germany, which emphasizes on-site care. The trauma care system was deficient in most developing countries. During the past ten years, rapid progresses have been achieved in trauma care system construction in China which refers to "Chinese regional trauma care system(CRTCS)". CRTCS is established in one administrative region, with one large tertiary hospital as trauma center and five to six secondary hospitals as trauma care sites to form the closed-cycle regional trauma triage and transportation protocols. After several years of construction and implementation, CRTCS is considered to be a feasible new trauma care system in line with the characteristics of China's national conditions, which can significantly shorten the time of trauma treatment and reduce the mortality of trauma. It is worthy of reference for developing countries.

The anatomical, electrophysiological and histological observations of muscle contraction units in rabbits: a new perspective on nerve injury and regeneration

In the conventional view a muscle is composed of intermediate structures before its further division into microscopic muscle fibers. Our experiments in mice have confirmed this intermediate structure is composed of the lamella cluster formed by motor endplates, the innervating nerve branches and the corresponding muscle fibers, which can be viewed as an independent structural and functional unit. In this study, we verified the presence of these muscle construction units in rabbits. The results showed that the muscular branch of the femoral nerve sent out 4–6 nerve branches into the quadriceps and the tibial nerve sent out 4–7 nerve branches into the gastrocnemius. When each nerve branch of the femoral nerve was stimulated from the most lateral to the medial, the contraction of the lateral muscle, intermediate muscle and medial muscle of the quadriceps could be induced by electrically stimulating at least one nerve branch. When stimulating each nerve branch of the tibial nerve from the lateral to the medial, the muscle contraction of the lateral muscle 1, lateral muscle 2, lateral muscle 3 and medial muscle of the gastrocnemius could be induced by electrically stimulating at least one nerve branch. Electrical stimulation of each nerve branch resulted in different electromyographical waves recorded in different muscle subgroups. Hematoxylin-eosin staining showed most of the nerve branches around the neuromuscular junctions consisted of one individual neural tract, a few consisted of two or more neural tracts. The muscles of the lower limb in the rabbit can be subdivided into different muscle subgroups, each innervated by different nerve branches, thereby allowing much more complex muscle activities than traditionally stated. Together, the nerve branches and the innervated muscle subgroups can be viewed as an independent structural and functional unit. This study was approved by the Animal Ethics Committee of Peking University People’s Hospital (approval No. 2019PHE027) on October 20, 2019.

Early versus Delayed Surgery for Acute Traumatic Cervical/Thoracic Spinal Cord Injury in Beijing, China: The Results of a Prospective, Multicenter Nonrandomized Controlled Trial

OBJECTIVES

To compare the effects of early surgery (within 24 h) and delayed surgery on the outcomes of patients with acute cervical/thoracic spinal cord injury (SCI) in Beijing, China.

METHODS

We conducted a clinical trial involving patients who were aged 16-85 years, had acute SCI from 1 June 2016 to 1 June 2019 in Beijing. The enrolled patients were divided into two groups according to the timing of surgical decompression. The primary outcome was the ordinal change in the American Spinal Injury Association Impairment Scale (AIS) grade. The secondary outcomes included the surgical time, volume of surgical bleeding, rate of admission to the intensive care unit (ICU), length of stay in the ICU, duration of mechanical ventilation, length of hospital stay, and postoperative complications. And the time consumption of different phases before operation was recorded for the patients transported to hospital by ambulance.

RESULTS

A total of 148 patients were included in the study, including 55 in the early surgery group and 93 in the delayed surgery group. At 52 weeks post-surgery, 27.3% of the patients in the early surgery group showed AIS improvement by at least two grades, compared to 8.7% of the patients in the delayed surgery group (P = 0.102). According to the logistic regression analysis, the odds of at least a two-grade AIS improvement was six times higher among the patients who underwent early surgery than among those who underwent delayed surgery (OR = 6.66, 95%CI 1.14-38.84). The delay surgery group consumed significantly more time in the phases of transfer and inspection or examination than the early surgery group, and the Chinese regional trauma treatment system was widely used in the early surgery group.

CONCLUSION

Decompression within 24 h after SCI can improve patients' recovery of neurological function without increasing the incidence of postoperative complications and surgical risks. The Chinese regional trauma treatment system can improve the diagnosis and treatment efficiency of patients with acute SCI and speed up the operation timing.

Chitin scaffold combined with autologous small nerve repairs sciatic nerve defects

Although autologous nerve transplantation is the gold standard for treating peripheral nerve defects, it has many clinical limitations. As an alternative, various tissue-engineered nerve grafts have been developed to substitute for autologous nerves. In this study, a novel nerve graft composed of chitin scaffolds and a small autologous nerve was used to repair sciatic nerve defects in rats. The novel nerve graft greatly facilitated regeneration of the sciatic nerve and myelin sheath, reduced atrophy of the target muscle, and effectively restored neurological function. When the epineurium of the small autogenous nerve was removed, the degree of nerve regeneration was similar to that which occurs after autogenous nerve transplantation. These findings suggest that our novel nerve graft might eventually be a new option for the construction of tissue-engineered nerve scaffolds. The study was approved by the Research Ethics Committee of Peking University People's Hospital (approval No. 2019PHE27) on October 18, 2019.

Combining chitin biological conduits with small autogenous nerves and platelet-rich plasma for the repair of sciatic nerve defects in rats

Aims

Peripheral nerve defects are often difficult to recover from, and there is no optimal repair method. Therefore, it is important to explore new methods of repairing peripheral nerve defects. This study explored the efficacy of nerve grafts constructed from chitin biological conduits combined with small autogenous nerves (SANs) and platelet‐rich plasma (PRP) for repairing 10‐mm sciatic nerve defects in rats.

Methods

To prepare 10‐mm sciatic nerve defects, SANs were first harvested and PRP was extracted. The nerve grafts consisted of chitin biological conduits combined with SAN and PRP, and were used to repair rat sciatic nerve defects. These examinations, including measurements of axon growth efficiency, a gait analysis, electrophysiological tests, counts of regenerated myelinated fibers and observations of their morphology, histological evaluation of the gastrocnemius muscle, retrograde tracing with Fluor‐Gold (FG), and motor endplates (MEPs) distribution analysis, were conducted to evaluate the repair status.

Results

Two weeks after nerve transplantation, the rate and number of regenerated axons in the PRP‐SAN group improved compared with those in the PRP, SAN, and Hollow groups. The PRP‐SAN group exhibited better recovery in terms of the sciatic functional index value, composite action potential intensity, myelinated nerve fiber density, myelin sheath thickness, and gastrectomy tissue at 12 weeks after transplantation, compared with the PRP and SAN groups. The results of FG retrograde tracing and MEPs analyses showed that numbers of FG‐positive sensory neurons and motor neurons as well as MEPs distribution density were higher in the PRP‐SAN group than in the PRP or SAN group.

Conclusions

Nerve grafts comprising chitin biological conduits combined with SANs and PRP significantly improved the repair of 10‐mm sciatic nerve defects in rats and may have therapeutic potential for repairing peripheral nerve defects in future applications.

Risk factors for cement leakage and nomogram for predicting the intradiscal cement leakage after the vertebra augmented surgery

Background

Vertebral augmentation is the first-line treatment for the osteoporosis vertebral compression fractures. Bone cement leakage is the most common complication of this surgery. This study aims to assess the risk factors for different types of cement leakage and provides a nomogram for predicting the cement intradiscal leakage.

Methods

We retrospectively reviewed 268 patients who underwent vertebral augmentation procedure between January 2015 and March 2019. The cement leakage risk factors were evaluated by univariate analysis. Different types of cement leakage risk factors were identified by the stepwise logistic analysis. We provided a nomogram for predicting the cement intradiscal leakage and used the concordance index to assess the prediction ability.

Results

A total of 295 levels of vertebrae were included, with a leakage rate of 32.5%. Univariate analysis showed delayed surgery and lower vertebral compression ratio were the independent risk factors of cement leakage. The stepwise logistic analysis revealed percutaneous vertebroplasty was a risk factor in vein cement leakage; delayed surgery, preoperative compression ratio, and upper endplate disruption were in intradiscal cement leakage; age, preoperative fracture severity, and intravertebral vacuum cleft were in perivertebral soft tissue cement leakage; no factor was in spinal canal cement leakage. The nomogram for intradiscal cement leakage had a precise prediction ability with an original concordance index of 0.75.

Conclusions

Delayed surgery and more vertebral compression increase the risk of cement leakage. Different types of cement leakage have different risk factors. We provided a nomogram for precise predicting the intradiscal cement leakage.

Prognostic Implications of Preoperative Pneumonia for Geriatric Patients Undergoing Hip Fracture Surgery or Arthroplasty

Objective

To report outcomes of geriatric patients undergoing hip fracture surgery or arthroplasty with or without preoperative pneumonia and to evaluate the influence of pneumonia severity on patient prognosis.

Methods

In this single center retrospective study, we included geriatric patients (≥60 years old) who had undergone hip fracture surgery or arthroplasty at Peking University People's Hospital from January 2008 to September 2018. Patients with fractures caused by neoplasms or patients with incomplete clinical data were excluded. Using logistic regression and the CURB‐65 (confusion, uremia, respiratory rate, blood pressure, and age ≥65 years) score as a prediction tool of 1‐year mortality, the effect of preoperative pneumonia on 1‐year mortality was evaluated. Survival of patients with different response to pneumonia‐specific therapy and survival of patients with different pneumonia severity (evaluated with CURB‐65 score) were analyzed using Cox regression.

Results

A total of 1386 patients were included; among them, 109 patients (7.86%) were diagnosed with preoperative pneumonia. Outcomes were evaluated in August 2019 (at least 1 year after surgery for all patients). Compared to patients without preoperative pneumonia, patients with this condition had higher 30‐day mortality (11.9% vs 5%, P = 0.002) and 1‐year mortality rates (33.9% vs 16.3%, P < 0.001) and higher incidence of acute heart failure (7.3% vs 3.4%, P = 0.034) and acute kidney injury (5.5% vs 1.8%, P = 0.009). In multivariate regression, preoperative pneumonia was identified as an independent predictor of 1‐year mortality (odds ratio [OR], 1.45; 95% confidence interval [CI] 1.39–3.52; P = 0.021), with other factors including age (≥84 years, OR, 1.46; 95% CI 1.08–1.60; P = 0.027), body mass index (<18.5 kg/m², OR 2.23; 95% CI 1.52–3.17, P < 0.001), anesthesia type (regional, OR 0.87; 95% CI 0.19–0.97, P = 0.042), preoperative pneumonia (OR 1.45; 95% CI 1.39–3.52; P = 0.002), congestive heart failure (OR 2.05, 95% CI 1.57–6.21, P < 0.001), chronic kidney disease (OR 1.73; 95% CI 1.50–2.62; P < 0.001). There was a trend of increased 1‐year mortality as the CURB‐65 score elevated (P for trend = 0.006). Cox regression reveals a higher risk of mortality in patient with preoperative pneumonia, especially in patients with no radiologic improvements after therapy (log‐rank, P = 0.035). Analysis of the impact of pneumonia severity on patient survival using Cox regression reveals that a CURB‐65 score ≥3 indicated a lower rate of survival (CURB‐65 score of 3: hazard ratio [HR] 3.12, 95% CI 1.39–7.03, P = 0.006; score of 4: HR 3.41, 95% CI 1.69–6.92, P = 0.001; score of 5: HR 6.28, 95% CI 2.95–13.35, P < 0.001).

Conclusion

In this single center retrospective study, preoperative pneumonia was identified as an independent risk factor of 1‐year mortality in geriatric patients undergoing hip fracture surgery or arthroplasty. A CURB‐65 score ≥3 indicated a higher risk of mortality.

Assessment of thoracic volume changes after the collapse of lateral rib fractures based on chest computed tomography data: computer simulation and a multiple variable linear regression analysis

Background

Chest blunt trauma (CBT) and the resultant rib fractures often lead to thoracic collapse. The purpose of this study was to explore the effect of displacement of the rib fracture and thoracic collapse on the thoracic volume by using normal chest CT data.

Methods

In this retrospective study, seven consecutive normal participants were selected from our hospital between June and July 2018. Normal thoracic models were reconstructed, followed by simulation of lateral fractures through the 4th to 9th ribs under three collapse modes with 1–5 cm of collapse. The thoracic collapse models (n = 630) were reconstructed using 3Dmax 2014. We calculated the thoracic volume and reduction percentage for each thoracic collapse model. Linear regression-based comparisons of thoracic volume reductions were performed.

Results

In all three collapse modes, the degree of the collapse was linearly correlated with the mean thoracic volume reduction. The reduction percentage in the posterior collapse mode was higher than that in the anterior collapse mode (P < 0.001). The largest volume reductions in the anterior, posterior, and simultaneous collapse models were in the 6th rib fracture model (P < 0.001), 8th rib fracture model (P < 0.001), and 7th rib fracture model (P < 0.001), respectively.

Conclusions

The influences of rib fracture displacement and collapse on the thoracic volume in the 6th through 8th ribs are critical in lateral rib fractures. For patients with 6th to 8th rib fractures and posterior rib collapse, surgical intervention to restore thoracic volume may be more essential.

Hip Replacement as Alternative to Intramedullary Nail in Elderly Patients with Unstable Intertrochanteric Fracture: A Systematic Review and Meta-Analysis

Objective

To evaluate the efficacy and safety of hip replacement and intramedullary nails for treating unstable intertrochanteric fractures in elderly patients.

Methods

Randomized clinical trials (RCTs) to compare hip replacement with intramedullary nail in the management of elderly patients with unstable intertrochanteric femur fracture were retrieved from Cochrane Library (up to January 2018), CNKI (China National Knowledge Infrastructure), Wanfang Data, PubMed, and Embase. The methodological quality of the included trials was assessed using the Cochrane risk of bias assessment tool, and relevant data was extracted. Statistical analysis was performed by Revman 5.3. Where possible, we performed the limited pooling of data.

Results

Fourteen trials including a total of 1067 participants aged 65 and above were included for qualitative synthesis and meta‐analysis. The methodological quality of the included study was poor. The meta‐analysis indicated that the hip replacement group benefited more than the intramedullary nail group in terms of the bearing load time (WMD ‐14.61, 95% CI −21.51 to −7.7, P < 0.0001), mechanical complications (OR 0.34, 95% CI 0.21 to 0.57, P < 0.0001), and post‐operative complications (OR 0.46, 95% CI 0.22 to 0.93, P = 0.03). While the intramedullary nail was superior to arthroplasty regarding the intraoperative blood loss (WMD 58.36, 95% CI 30.77 to 85.94, P < 0.0001). However, there were no statistical significances in the length of surgery (WMD 5.27, 95% CI 4.23 to 14.77, P = 0.28), units of blood transfusion (WMD 0.34, 95% CI ‐0.16 to 0.85, P = 0.18), length of hospital stay (WMD ‐1.00, 95% CI ‐2.93 to 0.93, P = 0.31), Harris hip score (WMD 0.31, 95% CI ‐0.39 to 1.01, P = 0.38), and mortality (OR 1.24, 95% CI 0.12 to 13.10, P = 0.86).

Conclusions

This systematic review and meta‐analysis provided evidence for the efficacy and safety of hip replacement and intramedullary nail in treating unstable intertrochanteric fractures. However, the results should be interpreted cautiously because of methodological limitations and publication bias.

Risk Factors for Functional Outcomes of the Elderly with Intertrochanteric Fracture: A Retrospective Cohort Study

Objective

To identify baseline factors relevant to functional outcomes and health‐related quality of life in the elderly with intertrochanteric fractures.

Methods

For the present study, 168 patients with intertrochanteric fracture who were assigned to different treatments between January 2016 and December 2017 were retrospectively selected. Hip function was assessed by Harris hip score (HHS), and health‐related quality of life was evaluated by Barthel index (BI) of activities of daily living (ADL) and EuroQol 5‐dimensions (EQ‐5D) score, respectively. Data were analyzed by t‐test, ANOVA, Pearson's correlation, χ²‐test, and multivariate linear regression.

Results

A total of 164 (97.6%) patients completed the follow‐up, with an average follow‐up time of 15.7 ± 6.9 months; 39 (23.8%) patients died during the follow‐up period and 125 (76.2%) patients were eligible for the functional analysis. HHS at final follow‐up of 125 patients was 71.8 ± 13.1, and the following were associated with hip functional recovery: age (−0.45, 95% confidence interval (CI) −0.73 to −0.18, P < 0.01), serum albumin (0.65, 95% CI 0.04 to 1.27, P < 0.05), and ADL at discharge (0.18, 95% CI 0.01 to 0.33, P < 0.05). The Barthel index at final follow up in this cohort was 80.2 ± 18.1, and multivariable linear regression analysis showed that age (−0.49, 95% CI −0.85 to −0.12; P < 0.05), ADL score at discharge (0.29, 95% CI 0.07 to 0.51; P < 0.05) and internal fixation (16.3, 95% CI 3.3 to 29.3; P < 0.05) were associated with ADL at final follow‐up. EQ‐5D at final follow‐up was 0.74 ± 0.2, with which HHS (0.012, 95% CI 0.011 to 0.013; P < 0.01) was positively associated.

Conclusion

We identify several baseline factors associated with hip functional outcome, health utility, and ADL in the elderly after an intertrochanteric fracture, of which we could modify mutable factors to achieve better outcomes. These findings could help to inform treatment and functional prognosis.

Temporal changes in the spinal cord transcriptome after peripheral nerve injury

Peripheral nerve injury may trigger changes in mRNA levels in the spinal cord. Finding key mRNAs is important for improving repair after nerve injury. This study aimed to investigate changes in mRNAs in the spinal cord following sciatic nerve injury by transcriptomic analysis. The left sciatic nerve denervation model was established in C57BL/6 mice. The left L4-6 spinal cord segment was obtained at 0, 1, 2, 4 and 8 weeks after severing the sciatic nerve. mRNA expression profiles were generated by RNA sequencing. The sequencing results of spinal cord mRNA at 1, 2, 4, and 8 weeks after severing the sciatic nerve were compared with those at 0 weeks by bioinformatic analysis. We identified 1915 differentially expressed mRNAs in the spinal cord, of which 4, 1909, and 2 were differentially expressed at 1, 4, and 8 weeks after sciatic nerve injury, respectively. Sequencing results indicated that the number of differentially expressed mRNAs in the spinal cord was highest at 4 weeks after sciatic nerve injury. These mRNAs were associated with the cellular response to lipid, ATP metabolism, energy coupled proton transmembrane transport, nuclear transcription factor complex, vacuolar proton-transporting V-type ATPase complex, inner mitochondrial membrane protein complex, tau protein binding, NADH dehydrogenase activity and hydrogen ion transmembrane transporter activity. Of these mRNAs, Sgk1, Neurturin and Gpnmb took part in cell growth and development. Pathway analysis showed that these mRNAs were mainly involved in aldosterone-regulated sodium reabsorption, oxidative phosphorylation and collecting duct acid secretion. Functional assessment indicated that these mRNAs were associated with inflammation and cell morphology development. Our findings show that the number and type of spinal cord mRNAs involved in changes at different time points after peripheral nerve injury were different. The number of differentially expressed mRNAs in the spinal cord was highest at 4 weeks after sciatic nerve injury. These results provide reference data for finding new targets for the treatment of peripheral nerve injury, and for further gene therapy studies of peripheral nerve injury and repair. The study procedures were approved by the Ethics Committee of the Peking University People's Hospital (approval No. 2017PHC004) on March 5, 2017.

Qian-Zheng-San promotes regeneration after sciatic nerve crush injury in rats

Qian-Zheng-San, a traditional Chinese prescription consisting of Typhonii Rhizoma, Bombyx Batryticatus, Scorpio, has been found to play an active therapeutic role in central nervous system diseases. However, it is unclear whether Qian-Zheng-San has therapeutic value for peripheral nerve injury. Therefore, we used Sprague-Dawley rats to investigate this. A sciatic nerve crush injury model was induced by clamping the right sciatic nerve. Subsequently, rats in the treatment group were administered 2 mL Qian-Zheng-San (1.75 g/mL) daily as systemic therapy for 1, 2, 4, or 8 weeks. Rats in the control group were not administered Qian-Zheng-San. Rats in sham group did not undergo surgery and systemic therapy. Footprint analysis was used to assess nerve motor function. Electrophysiological experiments were used to detect nerve conduction function. Immunofluorescence staining was used to assess axon counts and morphological analysis. Immunohistochemical staining was used to observe myelin regeneration of the sciatic nerve and the number of motoneurons in the anterior horn of the spinal cord. At 2 and 4 weeks postoperatively, the sciatic nerve function index, nerve conduction velocity, the number of distant regenerated axons and the axon diameter of the sciatic nerve increased in the Qian-Zheng-San treatment group compared with the control group. At 2 weeks postoperatively, nerve fiber diameter, myelin thickness, and the number of motor neurons in the lumbar spinal cord anterior horn increased in the Qian-Zheng-San treatment group compared with the control group. These results indicate that Qian-Zheng-San has a positive effect on peripheral nerve regeneration.

Reinnervation of spinal cord anterior horn cells after median nerve repair using transposition with other nerves

Our previous studies have confirmed that during nerve transposition repair to injured peripheral nerves, the regenerated nerve fibers of motor neurons in the anterior horn of the spinal cord can effectively repair distal nerve and target muscle tissue and restore muscle motor function. To observe the effect of nerve regeneration and motor function recovery after several types of nerve transposition for median nerve defect (2 mm), 30 Sprague-Dawley rats were randomly divided into sham operation group, epineurial neurorrhaphy group, musculocutaneous nerve transposition group, medial pectoral nerve transposition group, and radial nerve muscular branch transposition group. Three months after nerve repair, the wrist flexion test was used to evaluate the recovery of wrist flexion after regeneration of median nerve in the affected limbs of rats. The number of myelinated nerve fibers, the thickness of myelin sheath, the diameter of axons and the cross-sectional area of axons in the proximal and distal segments of the repaired nerves were measured by osmic acid staining. The ratio of newly produced distal myelinated nerve fibers to the number of proximal myelinated nerve fibers was calculated. Wet weights of the flexor digitorum superficialis muscles were measured. Muscle fiber morphology was detected using hematoxylin-eosin staining. The cross-sectional area of muscle fibers was calculated to assess the recovery of muscles. Results showed that wrist flexion function was restored, and the nerve grew into the distal effector in all three nerve transposition groups and the epineurial neurorrhaphy group. There were differences in the number of myelinated nerve fibers in each group. The magnification of proximal to distal nerves was 1.80, 3.00, 2.50, and 3.12 in epineurial neurorrhaphy group, musculocutaneous nerve transposition group, medial pectoral nerve transposition group, and radial nerve muscular branch transposition group, respectively. Nevertheless, axon diameters of new nerve fibers, cross-sectional areas of axons, thicknesses of myelin sheath, wet weights of flexor digitorum superficialis muscle and cross-sectional areas of muscle fibers of all three groups of donor nerves from different anterior horn motor neurons after nerve transposition were similar to those in the epineurial neurorrhaphy group. Our findings indicate that donor nerve translocation from different anterior horn motor neurons can effectively repair the target organs innervated by the median nerve. The corresponding spinal anterior horn motor neurons obtain functional reinnervation and achieve some degree of motor function in the affected limbs.

Repair of long segmental ulnar nerve defects in rats by several different kinds of nerve transposition

Multiple regeneration of axonal buds has been shown to exist during the repair of peripheral nerve injury, which confirms a certain repair potential of the injured peripheral nerve. Therefore, a systematic nerve transposition repair technique has been proposed to treat severe peripheral nerve injury. During nerve transposition repair, the regenerated nerve fibers of motor neurons in the anterior horn of the spinal cord can effectively grow into the repaired distal nerve and target muscle tissues, which is conducive to the recovery of motor function. The aim of this study was to explore regeneration and nerve functional recovery after repairing a long-segment peripheral nerve defect by transposition of different donor nerves. A long-segment (2 mm) ulnar nerve defect in Sprague-Dawley rats was repaired by transposition of the musculocutaneous nerve, medial pectoral nerve, muscular branches of the radial nerve and anterior interosseous nerve (pronator quadratus muscle branch). In situ repair of the ulnar nerve was considered as a control. Three months later, wrist flexion function, nerve regeneration and innervation muscle recovery in rats were assessed using neuroelectrophysiological testing, osmic acid staining and hematoxylin-eosin staining, respectively. Our findings indicate that repair of a long-segment ulnar nerve defect with different donor nerve transpositions can reinnervate axonal function of motor neurons in the anterior horn of spinal cord and restore the function of affected limbs to a certain extent.

Repair of peripheral nerve defects by nerve transposition using small gap bio-sleeve suture with different inner diameters at both ends

During peripheral nerve transposition repair, if the diameter difference between transposed nerves is large or multiple distal nerves must be repaired at the same time, traditional epineurial neurorrhaphy has the problem of high tension at the suture site, which may even lead to the failure of nerve suture. We investigated whether a small gap bio-sleeve suture with different inner diameters at both ends can be used to repair a 2-mm tibial nerve defect by proximal transposition of the common peroneal nerve in rats and compared the results with the repair seen after epineurial neurorrhaphy. Three months after surgery, neurological function, nerve regeneration, and recovery of nerve innervation muscle were assessed using the tibial nerve function index, neuroelectrophysiological testing, muscle biomechanics and wet weight measurement, osmic acid staining, and hematoxylin-eosin staining. There was no obvious inflammatory reaction and neuroma formation in the tibial nerve after repair by the small gap bio-sleeve suture with different inner diameters at both ends. The conduction velocity, muscle strength, wet muscle weight, cross-sectional area of muscle fibers, and the number of new myelinated nerve fibers in the bio-sleeve suture group were similar to those in the epineurial neurorrhaphy group. Our findings indicate that small gap bio-sleeve suture with different inner diameters at both ends can achieve surgical suture between nerves of different diameters and promote regeneration and functional recovery of injured peripheral nerves.

Tissue engineering for the repair of peripheral nerve injury

Peripheral nerve injury is a common clinical problem and affects the quality of life of patients. Traditional restoration methods are not satisfactory. Researchers increasingly focus on the field of tissue engineering. The three key points in establishing a tissue engineering material are the biological scaffold material, the seed cells and various growth factors. Understanding the type of nerve injury, the construction of scaffold and the process of repair are necessary to solve peripheral nerve injury and promote its regeneration. This review describes the categories of peripheral nerve injury, fundamental research of peripheral nervous tissue engineering and clinical research on peripheral nerve scaffold material, and paves a way for related research and the use of conduits in clinical practice.

Establishment of trauma treatment teams within a regional severe trauma treatment system in China: study protocol for a national cluster-randomised trial

INTRODUCTION

The implementation of first aid processes for patients with trauma in China faces significant challenges. These challenges include long response times of prehospital first aid services, lack of information exchange between prehospital first aid services and in-hospital emergency services, lack of a professional rescue team in the majority of hospitals, and lack of standardised training for prehospital and in-hospital emergency personnel. The purpose of the trial is to guide the establishment of an urban trauma treatment system in China, highlight the construction of a trauma treatment system tailored to the Chinese context and improve levels of medical treatment by selecting approximately 100 counties across China as pilots to establish a regional trauma treatment system.

METHODS AND ANALYSIS

A cluster-randomised controlled trial will be performed in 98 county-level research institutes. Included research institutes will be randomised into an experimental group and a control group. Patients in both experimental and control groups will receive basic treatments. A trauma treatment team will be established in the experimental group. The primary outcome measure is in-hospital mortality rate of patients. The secondary outcome measures include mortality rate of patients within 30 days after trauma attack and within 30 days after discharge, the time between arrival in the institution and receiving consultation, and the time from admission to the start of surgery. The effects of establishment of trauma treatment teams on the treatment of severe trauma will be evaluated in all counties.

ETHICS AND DISSEMINATION

The procedures have been approved by The Medical Ethics Committee of Peking University People's Hospital (No.2017PHB098-01) and conform to the Declaration of Helsinki. Data will be collected and analysed in accordance with participant privacy laws and regulations. Results will be disseminated through policy briefs, workshops, peer-reviewed publications and conferences.

TRIAL REGISTRATION NUMBER

NCT03363880; Pre-results.

A Modified Foot and Ankle Score for Assessing Patient Outcomes After First Metatarsophalangeal Arthrodesis

First metatarsophalangeal (MTP) arthrodesis is commonly used to treat many end-stage first MTP diseases. The most widely used scale for measuring the clinical outcomes after this procedure, the American Orthopaedic Foot and Ankle Society Hallux Metatarsophalangeal-Interphalangeal scale, has not been adequately validated and does not measure specific foot functions. Another outcome measure, the patient-reported Foot and Ankle Outcome Score (FAOS) has acceptable construct validity but poor content validity. The FAOS scale has 42 questions, many of which are unrelated to the hallux. We designed a short-form FAOS (sf-FAOS) consisting of 11 questions that are more relevant to first MTP arthrodesis. The sf-FAOS includes a pain subscale and a function subscale, and the score of each subscale ranges from 0 (worst outcome) to 100 (best outcome). Our study has shown that the sf-FAOS scale has acceptable validity, reliability, and responsiveness. In 21 feet (16 patients) with hallux valgus after >1 year of follow-up, the mean sf-FAOS pain score had improved by 44.9 points after surgery (from 51.2 to 96.0; p < .001), and the mean sf-FAOS function score had improved by 22.5 points (from 47.3 to 69.8; p <.001). The improvement in the function score for running and jumping was limited.

Chitin biological absorbable catheters bridging sural nerve grafts transplanted into sciatic nerve defects promote nerve regeneration

AIMS

To investigate the efficacy of chitin biological absorbable catheters in a rat model of autologous nerve transplantation.

METHODS

A segment of sciatic nerve was removed to produce a sciatic nerve defect, and the sural nerve was cut from the ipsilateral leg and used as a graft to bridge the defect, with or without use of a chitin biological absorbable catheter surrounding the graft. The number and morphology of regenerating myelinated fibers, nerve conduction velocity, nerve function index, triceps surae muscle morphology, and sensory function were evaluated at 9 and 12 months after surgery.

RESULTS

All of the above parameters were improved in rats in which the nerve graft was bridged with chitin biological absorbable catheters compared with rats without catheters.

CONCLUSIONS

The results of this study indicate that use of chitin biological absorbable catheters to surround sural nerve grafts bridging sciatic nerve defects promotes recovery of structural, motor, and sensory function and improves muscle fiber morphology.

["Time-angle measurement" reduction evaluation technique and clinical evaluation of proximal humerus fracture]

OBJECTIVE

To evaluate the functional outcome and the complication rate after open reduction and internal fixation of proximal humeral fractures with a "time-angle measurement" reduction evaluation technique, to assess the acceptance of the fracture reduction and to estimate the result of the sur-gery.

METHODS

Forty-six patients [mean age: (66.2±14.9) years] with an acute proximal humeral fracture were managed with open reduction and internal fixation with this reduction evaluation technique from January 2012 to December 2013. According to the Neer classification, there were 6 two- part fractures, 25 three-part fractures and 15 four-part fractures. The functional outcome was evaluated for each patient using the Constant-Murley score; radiographic evaluation was also conducted and complications were recorded. The postoperative shoulder function recovery and imaging findings were followed up to evaluate the guiding significance of this reduction evaluation technique in the clinical treatment of this kind of fracture.

RESULTS

In the study, 46 patients had been followed up for 13-36 months, and the average follow-up time was (23.5±7.3) months. All the patients achieved fracture healing 3 months after operation. The average head-shaft angle was (124±3.5) degrees. According to the Constant scoring system, 29 patients (63%) had excellent, 14 patients (30%) had good, and 3 patients (7%) had poor results. The most common complications were pain (7/65) and restricted movement of the shoulder (5/46). There were no cases of screw penetration, necrosis of humeral head, deep tissue infection, nonunion of fracture and axillary nerve injury after operation.

CONCLUSION

For appropriate cases of displaced proximal humeral fractures, surgical treatment with application of "time-angle measurement" reduction evaluation technique that was introduced in the present study can lead to a good functional outcome, and the technique of reduction assessment should be regarded as a reasonable reference standard in the treatment of displaced proximal humerus fracture.

Short-term observations of the regenerative potential of injured proximal sensory nerves crossed with distal motor nerves

Motor nerves and sensory nerves conduct signals in different directions and function in different ways. In the surgical treatment of peripheral nerve injuries, the best prognosis is obtained by keeping the motor and sensory nerves separated and repairing the nerves using the suture method. However, the clinical consequences of connections between sensory and motor nerves currently remain unknown. In this study, we analyzed the anatomical structure of the rat femoral nerve, and observed the motor and sensory branches of the femoral nerve in the quadriceps femoris. After ligation of the nerves, the proximal end of the sensory nerve was connected with the distal end of the motor nerve, followed by observation of the changes in the newly-formed regenerated nerve fibers. Acetylcholinesterase staining was used to distinguish between the myelinated and unmyelinated motor and sensory nerves. Denervated muscle and newly formed nerves were compared in terms of morphology, electrophysiology and histochemistry. At 8 weeks after connection, no motor nerve fibers were observed on either side of the nerve conduit and the number of nerve fibers increased at the proximal end. The proportion of newly-formed motor and sensory fibers was different on both sides of the conduit. The area occupied by autonomic nerves in the proximal regenerative nerve was limited, but no distinct myelin sheath was visible in the distal nerve. These results confirm that sensory and motor nerves cannot be effectively connected. Moreover, the change of target organ at the distal end affects the type of nerves at the proximal end.

Autologous transplantation with fewer fibers repairs large peripheral nerve defects

Peripheral nerve injury is a serious disease and its repair is challenging. A cable-style autologous graft is the gold standard for repairing long peripheral nerve defects; however, ensuring that the minimum number of transplanted nerve attains maximum therapeutic effect remains poorly understood. In this study, a rat model of common peroneal nerve defect was established by resecting a 10-mm long right common peroneal nerve. Rats receiving transplantation of the common peroneal nerve in situ were designated as the in situ graft group. Ipsilateral sural nerves (10–30 mm long) were resected to establish the one sural nerve graft group, two sural nerves cable-style nerve graft group and three sural nerves cable-style nerve graft group. Each bundle of the peroneal nerve was 10 mm long. To reduce the barrier effect due to invasion by surrounding tissue and connective-tissue overgrowth between neural stumps, small gap sleeve suture was used in both proximal and distal terminals to allow repair of the injured common peroneal nerve. At three months postoperatively, recovery of nerve function and morphology was observed using osmium tetroxide staining and functional detection. The results showed that the number of regenerated nerve fibers, common peroneal nerve function index, motor nerve conduction velocity, recovery of myodynamia, and wet weight ratios of tibialis anterior muscle were not significantly different among the one sural nerve graft group, two sural nerves cable-style nerve graft group, and three sural nerves cable-style nerve graft group. These data suggest that the repair effect achieved using one sural nerve graft with a lower number of nerve fibers is the same as that achieved using the two sural nerves cable-style nerve graft and three sural nerves cable-style nerve graft. This indicates that according to the ‘multiple amplification’ phenomenon, one small nerve graft can provide a good therapeutic effect for a large peripheral nerve defect.

[New treatment for peripheral nerve defects: nerve elongation]

Peripheral nerve defects are still a major challenge in clinical practice, and the most commonly used method of treatment for peripheral nerve defects is nerve transplantation, which has certain limitations and shortcomings, so new repair methods and techniques are needed. The peripheral nerve is elongated in limb lengthening surgery without injury, from which we got inspirations and proposed a new method to repair peripheral nerve defects: peripheral nerve elongation. The peripheral nerve could beelongated by a certain percent, but the physiological change and the maximum elongation range were still unknown. This study discussed the endurance, the physiological and pathological change of peripheral nerve elongation in detail, and got a lot of useful data. First, we developed peripheral nerve extender which could match the slow and even extension of peripheral nerve. Then, our animal experiment result confirmed that the peripheral nerve had better endurance for chronic elongation than that of acute elongation and cleared the extensibility of peripheral nerve and the range of repair for peripheral nerve defects. Our result also revealed the histological basis and changed the rule for pathological physiology of peripheral nerve elongation: the most important structure foundation of peripheral nerve elongation was Fontana band, which was the coiling of nerve fibers under the epineurium, so peripheral nerve could be stretched for 8.5%-10.0% without injury because of the Fontana band. We confirmed that peripheral nerve extending technology could have the same repair effect as traditional nerve transplantation through animal experiments. Finally, we compared the clinical outcomes between nerve elongation and performance of the conventional method in the repair of short-distance transection injuries in human elbows, and the post-operative follow-up results demonstrated that early neurological function recovery was better in the nerve elongation group than in the conventional group. On the whole, all of these experimental results revealed the physiological phenomenon of peripheral nerve elongation, and described the physiological change and stretch range in detail. The systematic research results have filled the blank in this field, which is very helpful for clinical limb lengthening surgery, the design of elongation surgery and the evaluation of the peripheral nerve stretch injury. Peripheral nerve elongation will become an innovative treatment technology in repairing peripheral nerve defects.

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.

Evaluation of the effects of standard rescue procedure on severe trauma treatment in china

Background:

This study aimed to evaluate the effects of standard rescue procedure (SRP) in improving severe trauma treatments in China.

Methods:

This study was conducted in 12 hospitals located in geographically and industrially different cities in China. A standard procedure on severe trauma rescue was established as a general rule for staff training and patient treatment. A regional network (system) efficiently integrating prehospital rescue, emergency room treatments, and hospital specialist treatments was built under the rule for information sharing and improving severe trauma treatments. Treatment outcomes were compared between before and 1 year after the implementation of the SRP.

Results:

The outcomes of a total of 74,615 and 12,051 trauma cases were collected from 12 hospitals before and after the implementation of the SRP. Implementation of the SRP led to efficient cooperation and information sharing of different treatment services. The emergency response time, prehospital transit time, emergency rescue time, consultation call time, and mortality rate of patients were 24.24 ± 4.32 min, 45.69 ± 3.89 min, 6.38 ± 1.05 min, 17.53 ± 0.72 min, and 33.82% ± 3.87% (n = 441), respectively, before the implementation of the standardization and significantly reduced to 10.11 ± 3.21 min, 22.39 ± 4.32 min, 3.26 ± 0.89 min, 3.45 ± 0.45 min, and 20.49% ± 3.11%, separately (n = 495, P < 0.05) after that.

Conclusions:

Staff training and SRP can significantly improve the efficiency of severe trauma treatments in China.

Comparison of commonly used retrograde tracers in rat spinal motor neurons

The purpose of this study was to investigate the effect of four fluorescent dyes, True Blue (TB), Fluoro-Gold (FG), Fluoro-Ruby (FR), and 1,1’-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate (DiI), in retrograde tracing of rat spinal motor neurons. We transected the muscle branch of the rat femoral nerve and applied each tracer to the proximal stump in single labeling experiments, or combinations of tracers (FG-DiI and TB-DiI) in double labeling experiments. In the single labeling experiments, significantly fewer labeled motor neurons were observed after FR labeling than after TB, FG, or DiI, 3 days after tracer application. By 1 week, there were no significant differences in the number of labeled neurons between the four groups. In the double-labeling experiment, the number of double-labeled neurons in the FG-DiI group was not significantly different from that in the TB-DiI group 1 week after tracer application. Our findings indicate that TB, FG, and DiI have similar labeling efficacies in the retrograde labeling of spinal motor neurons in the rat femoral nerve when used alone. Furthermore, combinations of DiI and TB or FG are similarly effective. Therefore, of the dyes studied, TB, FG and DiI, and combinations of DiI with TB or FG, are the most suitable for retrograde labeling studies of motor neurons in the rat femoral nerve.

Anterior subcutaneous transposition of the ulnar nerve improves neurological function in patients with cubital tunnel syndrome

Although several surgical procedures exist for treating cubital tunnel syndrome, the best surgical option remains controversial. To evaluate the efficacy of anterior subcutaneous transposition of the ulnar nerve in patients with moderate to severe cubital tunnel syndrome and to analyze prognostic factors, we retrospectively reviewed 62 patients (65 elbows) diagnosed with cubital tunnel syndrome who underwent anterior subcutaneous transposition. Preoperatively, the initial severity of the disease was evaluated using the McGowan scale as modified by Goldberg: 18 patients (28%) had grade IIA neuropathy, 20 (31%) had grade IIB, and 27 (42%) had grade III. Postoperatively, according to the Wilson & Krout criteria, treatment outcomes were excellent in 38 patients (58%), good in 16 (25%), fair in 7 (11%), and poor in 4 (6%), with an excellent and good rate of 83%. A negative correlation was found between the preoperative McGowan grade and the postoperative Wilson & Krout score. The patients having fair and poor treatment outcomes had more advanced age, lower nerve conduction velocity, and lower action potential amplitude compared with those having excellent and good treatment outcomes. These results suggest that anterior subcutaneous transposition of the ulnar nerve is effective and safe for the treatment of moderate to severe cubital tunnel syndrome, and initial severity, advancing age, and electrophysiological parameters can affect treatment outcome.

[Characteristics and perioperative management of hemophilia patients with fractures]

OBJECTIVE

To investigate the characteristics and perioperative management of hemophilia patients with fracture.

METHODS

Retrospectively, we analyzed 8 patients with hemophilia combined with fracture, who were admittted to our department from 2005 to 2013. Six patients were with hemophilia A and two with hemophilia B; Based on the severity of hemophilia, 2 cases were light, 3 moderate and 3 severe; Based on the location of fracture, 4 cases were femoral neck fractures, 1 femoral intertrochanteric fracture, 1 bilateral distal femur fractures, 1 tibiofibula fracture, and 1 humerus intercondylar fracture. Blood coagulation factor replacement therapy was conducted preoperatively, intraoperatively and postoperatively, All the patients underwent closed or open reduction and internal fixation or joint replacement. Also, we analyzed the perioperative complications and observed whether the fracture healed.

RESULTS

The average age was 33.5 years (14 to 47 years); In 6 cases, fractures occurred at femur, accounting for 75% of all the fractures; Femoral neck fracture was treated by closed reduction and hollow screws fixation; Femoral intertrochanteric fracture, distal femur fracture, and tibiofibula fracture were treated by open reduction and internal fixation with plate; Humerus intercondylar fracture was treated by elbow joint replacement. Intraoperative bleeding was from 50 to 600 mL, an average of 262 mL; Perioperatively, the average use of FVIII/activated prothrombin complex concentrates (APCC) was 358 U/kg (125 to 554 U/kg). Postoperatively, poor wound healing was observed in 2 patients, and the condition improved after symptomatic treatment; In patients with internal fixation, all the fractures united, and the average healing time was 14 weeks. No complications such as fixation loosening or rupture occurred after internal fixation.

CONCLUSION

Hemophilia combined with fracture mainly occurred in the young, and the site of fracture was given priority to femur. With perfect preoperative preparation, on the basis of the replacement therapy, hemophilia combined with fractures was safe for surgical treatment, and postoperative fractures healing wasgood. But the risk of poor wound healing was high.

[Research and promotion of severe trauma rescue standard]

Trauma is a global social problem, with the number of deaths up to 5.8 million all over the world annually. Currently, severe trauma has become the first cause of death in young adults in China. Nowadays, there are many problems in the trauma rescue system, including long pre-hospital transfer period, several secondary transfers, no information exchange between pre-hospital and in-hospital care, and the poor integrated treatment, which results in the situation that the overall treatment level of severe trauma in China is relatively low. In order to solve these problems, we carried out the research and promotion of severe trauma rescue standard, involving completing severe trauma information database, providing local rescue medical workers with standard training, and building up the information system for the linkage and warning of severe trauma. In addition, we developed and promoted the new standard system for severe trauma in 15 cities with 124 medical centers. Due to our research, the treatment ability of severe trauma in the pilot areas was enhanced, and the mortality and morbidity of severe trauma were reduced significantly. To sum up, we had got the expected results after implementing the project.

[Clinical characteristics and risk factors of newly developed vertebral fractures after vertebral augmentation]

OBJECTIVE

To identify the characteristics and risk factors of the refractures after percutaneous kyphoplasty (PKP) and percutaneous vertebroplasty (PVP).

METHODS

A retrospective analysis of 148 patients who had undergone PKP or PVP between March 2006 and October 2013 in Peking University People's Hospital was conducted. In the study, 29 patients with 42 refractured vertebra and 119 patients without refracture were included. All the patients were observed for a time of (34.4±26.8) months. Clinical, imaging and procedure related factors (gender, age, height, weight, body mass index, the level of the injured vertebra, the time interval between the procedure and the refracture, the level of the refractured vertebra, the bone cement volume injected, performed PKP or PVP,performed unilateral or bilateral, the percentage of anterior vertebral height restoration, the correction of the Cobb angle, cement diffusion, bone mineral density, presence or absence of diabetes mellitus, history of fractures of the whole body, anti-osteoporosis treatment, cement leakage) for each group were analyzed by Cox proportional hazards regression analysis.

RESULTS

Of all the patients,16 (55.17%, 16/29) had refractures in the adjacent vertebra, and 13 (44.83%, 13/29) had refractures in the nonadjacent vertebra. Refractures within 3 months accounted for 31.03% (9/29) of all the refractures, and within 1 year accounted for 55.17% (16/29). Both older age (P=0.027, HR=1.051, 95% CI=1.006-1.098) and a history of fractures of the whole body (P=0.012, HR=0.386, 95% CI=0.184-0.812) were statistically significant as the independent risk factors for predicting refractures. Others were not associated with refractures (P>0.05).

CONCLUSION

Older age and a history of fractures of the whole body are the independent risk factors of the refractures after PKP and PVP. The mechanism of the refractures after PKP and PVP is mainly the natural development of osteoporosis.

[Evaluation of the use of structure screw in PHILOS plate for treatment of proximal humerus fracture in Chinese]

OBJECTIVE

To measure vertical axis length of humerus head in patients with proximal humeral fractures and to evaluate the use of structure screws in proximal humerus internal locking osteosynthesis system (PHILOS).

METHODS

From January 2007 to February 2014,117 patients with proximal humerus fracture were treated by PHILOS plate. Preoperatively, all the patients tookanteroposterior X-ray of shoulder, and the vertical axis length of humerus head were measured, and the use of structure screws in PHILOS plate was observed.

RESULTS

There were 40 male and 77 female patients; The vertical axis length of humerus head in male patients was (47.64±3.44) mm, and the rate of structure screw use was 52.5%; The vertical axis length of humerus head in female patients was (42.46±3.21) mm, and the rate of structure screw use was 32.5%. The vertical axis length of humerus head and the rate of structure screw use had significant difference in the male and female groups (P<0.05).

CONCLUSION

The rate of structure screw use was low in the treatment of proximal humerus fracture by PHILOS plate, especially for women. We should improve the design of plate according to the anatomical characteristics of Chinese.

[Applying percutaneous placement of guide wire combined with true lateral view fluoroscopy proximal femoral nail anti-rotation fixation]

OBJECTIVE

To apply modified proximal femoral nail anti-rotation (PFNA) fixation techniques performed by percutaneous placement of guide wire combined with true lateral view and to make the procedures simpler.

METHODS

A retrospective study was used to analyze the clinical data of femoral intertrochanteric fractures cases, which were treated with conventional PFNA fixation or modified PFNA fixation performed by percutaneous placement guide wire combined with true lateral view in our hospital, from March, 2011 to May, 2014. In the study, 60 cases were followed for average 13 months. The operation time, the amount of bleeding, the fluoroscopy time, postoperative radiographic measurements (tip apex distance, TAD) and hip function scores were analyzed.

RESULTS

In modified PFNA group, the amount of bleeding, the operation time and the fluoroscopy time were (34.9±6.1) mL, (70.5±12.5) min, (63.6±9.7) s respectively. In conventional PFNA group,they were (47.8±6.7) mL, (80.6±17.1) min, (68.5±8.7) s respectively. There were significant differences in the above respects between the two groups (P were 0.006, 0.013, and 0.022 respectively). There were no significant differences in TAD, fracture healing time, postoperative hip scores between the two groups (P>0.05).

CONCLUSION

Fracture line is a natural entry point for some cases of femoral intertrochanteric fractures when we use proximal femoral nail anti-rotation to fix the fracture. Applying percutaneous insertion of the guide pin combined with true lateral view could reduce the operation time, amount of bleeding, and fluoroscopy time significantly, make the procedures simpler and acquire satisfactory results .

Sleeve bridging of the rhesus monkey ulnar nerve with muscular branches of the pronator teres: multiple amplification of axonal regeneration

Multiple-bud regeneration, i.e., multiple amplification, has been shown to exist in peripheral nerve regeneration. Multiple buds grow towards the distal nerve stump during proximal nerve fiber regeneration. Our previous studies have verified the limit and validity of multiple amplification of peripheral nerve regeneration using small gap sleeve bridging of small donor nerves to repair large receptor nerves in rodents. The present study sought to observe multiple amplification of myelinated nerve fiber regeneration in the primate peripheral nerve. Rhesus monkey models of distal ulnar nerve defects were established and repaired using muscular branches of the right forearm pronator teres. Proximal muscular branches of the pronator teres were sutured into the distal ulnar nerve using the small gap sleeve bridging method. At 6 months after suture, two-finger flexion and mild wrist flexion were restored in the ulnar-sided injured limbs of rhesus monkey. Neurophysiological examination showed that motor nerve conduction velocity reached 22.63 ± 6.34 m/s on the affected side of rhesus monkey. Osmium tetroxide staining demonstrated that the number of myelinated nerve fibers was 1,657 ± 652 in the branches of pronator teres of donor, and 2,661 ± 843 in the repaired ulnar nerve. The rate of multiple amplification of regenerating myelinated nerve fibers was 1.61. These data showed that when muscular branches of the pronator teres were used to repair ulnar nerve in primates, effective regeneration was observed in regenerating nerve fibers, and functions of the injured ulnar nerve were restored to a certain extent. Moreover, multiple amplification was subsequently detected in ulnar nerve axons.

Biological conduit small gap sleeve bridging method for peripheral nerve injury: regeneration law of nerve fibers in the conduit

The clinical effects of 2-mm small gap sleeve bridging of the biological conduit to repair peripheral nerve injury are better than in the traditional epineurium suture, so it is possible to replace the epineurium suture in the treatment of peripheral nerve injury. This study sought to identify the regeneration law of nerve fibers in the biological conduit. A nerve regeneration chamber was constructed in models of sciatic nerve injury using 2-mm small gap sleeve bridging of a biodegradable biological conduit. The results showed that the biological conduit had good histocompatibility. Tissue and cell apoptosis in the conduit apparently lessened, and regenerating nerve fibers were common. The degeneration regeneration law of Schwann cells and axons in the conduit was quite different from that in traditional epineurium suture. During the prime period for nerve fiber regeneration (2-8 weeks), the number of Schwann cells and nerve fibers was higher in both proximal and distal ends, and the effects of the small gap sleeve bridging method were better than those of the traditional epineurium suture. The above results provide an objective and reliable theoretical basis for the clinical application of the biological conduit small gap sleeve bridging method to repair peripheral nerve injury.

Use of nerve elongator to repair short-distance peripheral nerve defects: a prospective randomized study

Repair techniques for short-distance peripheral nerve defects, including adjacent joint flexion to reduce the distance between the nerve stump defects, "nerve splint" suturing, and nerve sleeve connection, have some disadvantages. Therefore, we designed a repair technique involving intraoperative tension-free application of a nerve elongator and obtained good outcomes in the repair of short-distance peripheral nerve defects in a previous animal study. The present study compared the clinical outcomes between the use of this nerve elongator and performance of the conventional method in the repair of short-distance transection injuries in human elbows. The 3-, 6-, and 12-month postoperative follow-up results demonstrated that early neurological function recovery was better in the nerve elongation group than in the conventional group, but no significant difference in long-term neurological function recovery was detected between the two groups. In the nerve elongation group, the nerves were sutured without tension, and the duration of postoperative immobilization of the elbow was decreased. Elbow function rehabilitation was significantly better in the nerve elongation group than in the control group. Moreover, there were no security risks. The results of this study confirm that the use of this nerve elongator for repair of short-distance peripheral nerve defects is safe and effective.

Local administration of icariin contributes to peripheral nerve regeneration and functional recovery

Our previous study showed that systemic administration of the traditional Chinese medicine Epimedium extract promotes peripheral nerve regeneration. Here, we sought to explore the therapeutic effects of local administration of icariin, a major component of Epimedium extract, on peripheral nerve regeneration. A poly(lactic-co-glycolic acid) biological conduit sleeve was used to bridge a 5 mm right sciatic nerve defect in rats, and physiological saline, nerve growth factor, icariin suspension, or nerve growth factor-releasing microsphere suspension was injected into the defect. Twelve weeks later, sciatic nerve conduction velocity and the number of myelinated fibers were notably greater in the rats treated with icariin suspension or nerve growth factor-releasing microspheres than those that had received nerve growth factor or physiological saline. The effects of icariin suspension were similar to those of nerve growth factor-releasing microspheres. These data suggest that icariin acts as a nerve growth factor-releasing agent, and indicate that local application of icariin after spinal injury can promote peripheral nerve regeneration.

Large animal models of human cauda equina injury and repair: evaluation of a novel goat model

Previous animal studies of cauda equina injury have primarily used rat models, which display significant differences from humans. Furthermore, most studies have focused on electrophysiological examination. To better mimic the outcome after surgical repair of cauda equina injury, a novel animal model was established in the goat. Electrophysiological, histological and magnetic resonance imaging methods were used to evaluate the morphological and functional outcome after cauda equina injury and end-to-end suture. Our results demonstrate successful establishment of the goat experimental model of cauda equina injury. This novel model can provide detailed information on the nerve regenerative process following surgical repair of cauda equina injury.

[Case-control study on effects of fracture of processus styloideus ulnae on prognosis after plate fixation for the treatment of distal radial fractures]

OBJECTIVE

To analyze effects of fracture of processus styloideus ulnae on prognosis in the treatment of distal radial fracture of type C according to AO classification.

METHODS

This was a retrospective case-control study, and the information was got ten through case evaluation and follow-up, including sex, age, patient satisfaction, Gartland & Werley score and radiographic score. There were 76 patient treated with open reduction and plate fixation in People's Hospital Affiliated to Peking University from July 2006 to July 2011. All the patients were divided into two groups: no combination with fracture of processus styloideus ulnae (group A, 56 cases), combination with fracture of processus styloideus ulnae (group B, 20 cases). The patients in group A and B were treated with open reduction and internal fixation; however the fracture of processus styloideus ulnae was not fixed. The indexes such as clinical data, bone grafting, joint movement, Gartland & Werley score and radiographic score were compared between two groups.

RESULTS

The ulnaris pain of patients in group B was more obvious than that in group A. The local VAS, palmar and dorsal flexion degree of wrist joint, motion VAS, patients satisfaction score, radial and ulnar deviation degree, pronation and supination of forearm degree, Gartland & Werley score and radiographic score were separately 0.1 ± 0.1, (51.1 ± 1.9)°, (60.2 ± 1.9)°, 0.6 ± 0.1 (23.1 ± 0.9)°, (28.7 ± 1.3)° (81.5 ± 2.6)°, (68.2 ± 2.7)° 1.9 ± 0.3, 89.6 ± 12.3 in group A; and separately 0.3 ± 0.3, (51.4 ± 2.3)°, (66.6 ± 1.7)°, 0.5 ± 0.2, (24.5 ± 2.0)°, (26.9 ± 1.8)°, (80.3 ± 2.5)°, (70.3 ± 3.7)°, 1.2 ± 0.4, 92.5 ± 7.5 in group B; there were no statistical differences in above indexes between two groups.

CONCLUSION

Whether the distal radial fracture with a concomitant unrepaired ulnar styloid fracture or not exerts no influence on mainly outcomes including function, radiography and motion of the wrist.

Effect of active Notch signaling system on the early repair of rat sciatic nerve injury

It is all known that dedifferentiated Schwann cells (SCs) play an important role in neural regeneration, and Notch signaling has complex and extensive regulatory functions in dedifferentiated SCs. So studies have focused on how to improve peripheral nerve repair by regulating proliferation and dedifferentiation in SCs with Notch signaling meloculars.We have found SCs can be activated when adding Recombinant rat jagged1/FC chimera (an activator of the Notch signaling system) in vivo. Compared with that of the control groups, at 4 weeks post-surgery nerve regeneration and functional rehabilitation in the Recombinant rat jagged1/FC chimera group were advanced significantly, and the expression of neurotrophic factors in the regenerated nerves was elevated largely. These results indicated that SCs activated by Notch signaling could promote nerve repair effectively in the early regenerative stage, suggesting the possible clinical application for the treatment of peripheral nerve defects.

[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.

[Generation and characterization of peripheral nerve animal model of pure motor/sensory nerve fibers]

OBJECTIVE

To generate peripheral nerve animal model of pure motor nerve fibers/pure sensory nerve fibers, and identify them.

METHODS

The SPF SD rats were adopted in this study, and divided into 3 groups. In group A, we ablated L2-L4 ventral roots (VRs) to generate peripheral nerve animal model of pure sensory fibers. In group B, we ablated L2-L4 dorsal root ganglions (DRGs) to generate peripheral nerve animal model of pure motor fibers. Two time end-points were set as 2 weeks and 4 weeks. Neuron cells in lumbar spinal cords were detected by immunohistochemical staining with antibody of neuronal nuclei (NeuN). Motor neuron cells in lumbar spinal cords of pure motor fiber animal models and sensory neuron cells in lumbar spinal cords of pure sensory fiber animal models were counted respectively, and then compared to that of normal animals. Femoral nerves distal to the furcation were stained in osmium tetroxide, and then myelinated nerve fibers in the muscle branch and cutaneous branch of femoral nerve were counted respectively.

RESULTS

The mean numbers of sensory neuron cells and motor neuron cells in normal lumbar spinal cords were 62.57 ± 1.02 and 29.73 ± 3.03 per 10 × 20 visual field respectively. For different end-points, the mean numbers of sensory neuron cells after ablating vental foots were 62.12 ± 1.77 (2 weeks), 62.15 ± 1.32 (4 weeks) per 10 × 20 visual field respectively; the mean numbers of motor neuron cells after ablating DRGs were 30.12 ± 0.44 (2 weeks), 30.00 ± 1.87 (4 weeks) per 10 × 20 visual field respectively. In group A, motor axons in muscle branch were degenerated as the sensory axons in muscle branch and cutaneous branch were not changed. The senory axons in femoral nerve for the two end-points were 1 558.17 ± 50.14 (2 weeks) and 1 544.00 ± 47.42 (4 weeks). In group B, sensory axons in muscle branch were degenerated as the motor axons were reserved. The motor axons in muscle branch for the two end-points were 387.67 ± 48.50 (2 weeks) and 393.50 ± 27.86 (4 weeks). There was no statistically significant difference in these mean numbers for the two end-points. The degenerating axons and myelin sheath had not been totally eliminated by the endpoint of 2 weeks.

CONCLUSION

Peripheral nerve animal model of pure motor fibers can be generated by ablating L2-L4 DRGs; peripheral nerve animal model of pure sensory fibers can be generated by ablating L2-L4 ventral roots. The degenerating axons and myelin sheath have been totally eliminated by the end-point of 4 weeks. Ablating the ventral roots does not influence the survival of sensory neuron cells; and ablating the DRGs does not influence the survival of motor neuron cells.