Repair of Sciatic Nerve Defect in Rats With Acellular Nerve Allograft Carrying Vascular Endothelial Cells.

BACKGROUND: Acellular nerve allografts (ANAs) were developed to replace the autologous nerve grafts (ANGs) to fill the peripheral nerve defects. Poor vascularization relative to ANGs has been a limitation of application of ANAs. METHODS: A total of 60 female Sprague-Dawley rats were assigned 3 groups. The rats in A group received ANGs, the rats in B group received ANAs, and the rats in C group were transplanted with ANA carrying endothelial cells (ANA + ECs). In the 1st, 2nd, 4th, and 12th postoperative weeks, 5 rats were selected from each group for evaluating sciatic function index (SFI), electrophysiology, maximum tetanic force recovery rate, tibialis anterior muscle weights recovery rate, and microvessel density. In the 12th postoperative week, the nerves were harvested and stained with toluidine blue and observed under an electron microscope to compare nerve fibers, myelin width, and G-ratio. RESULTS: All the rats survived. In the first and second postoperative weeks, more microvessels were found in the ANA + EC group. In the 12th postoperative week, the nerve fibers were more numerous, and G-ratio was smaller in the C group compared with the B group. The compound muscle action potential and maximum tetanic force recovery rate in the tibialis anterior muscle in the C group were better than those in the B group in the 12th postoperative week. The A group showed better performances in electrophysiology, maximum tetanic force, muscle wet weight, and nerve regeneration. CONCLUSION: ANA + ECs can promote early angiogenesis, promoting nerve regeneration and neurological function recovery.

Heterotopic Ossification in Burn Patients.

ABSTRACT: Heterotopic ossification (HO) is a known complication of burns. The incidence of this complication is low. The etiology is unclear, but experiment conducted about HO can be significant. Currently, there are still no targeted, effective preventive and therapeutic measures against it. In this study, the relevant literature is summarized to demonstrate the potential pathogenic mechanisms, diagnosis, prophylaxis, and treatment measures of HO in burn patients. Early diagnosis and treatment can be effective in improving the prognosis of patients.

Quantitative Characterization of Bone Viability of Femoral Head and Subchondral Bone by Using Single Photon Emission Computerized Tomography/Computerized Tomography (SPECT/CT).

BACKGROUND Vascularized fibular grafting (VFG) has been successfully employed for treating avascular necrosis of the femoral head (ANFH). In this study, we aimed to evaluate the bone viability of the femoral head and subchondral bone following VFG by using single photon emission computerized tomography and computerized tomography (SPECT/CT). MATERIAL AND METHODS Between March 2011 and June 2014, 14 ANFH patients (17 hips) treated with VFG at Zhongshan Hospital, Fudan University, were prospectively enrolled. The patients included 9 males and 5 females with an average age of 26.6 years (range, 18-34 years). According to the ARCO (Association Research Circulation Osseous) stage criteria, 3 hips corresponded to stage IIA, 4 hips to stage IIB, 2 hips to stage IIC, 5 hips to stage IIIA, and 3 hips to stage IIIB. A novel method based on SPECT/CT was developed to quantitative characterized the bone viability of femoral head and subchondral bone prior to surgery and at 3 months after VFG. All patients were followed for an average duration of 3.8 years (ranging 2.6-5.5 years). RESULTS The bone viability of the femoral head (Vfh) and subchondral bone (Vsb) of patients' hips at ARCO stage III was 58.9±7.6 and 48.9±6.1, respectively, which were significantly lower than the preoperative Vfh (78.1±5.2) and Vsb (69.8±4.3) of hips at stage II (P<0.05). The Vfh of hips at stage II improved to 104.0±9.7 at 3 months post-intervention, and there was no significant difference compared with the Vfh (97.3±7.4) of hips at stage III (P=0.15). The Vsb of hips at stage III improved to 80.4±7.3 at 3 months after VFG; however, this value was significantly lower than that of hips at stage II (92.7±5.5) (P<0.05). CONCLUSIONS The Vfh and Vsb of our patients were associated with their ARCO stages, and could be improved after vascularized fibular grafting procedure as measured by SPECT/CT.

Alteration of Sciatic Nerve Histology and Electrical Function After Compression and After Neurolysis in a Diabetic Rat Model.

BACKGROUND: Diabetic rats are more sensitive to nerve entrapment. This study was conducted to evaluate nerve function and histological changes in diabetic rats after nerve compression and subsequent decompression. METHODS: A total of 35 Wistar rats were included. The experimental group was divided into diabetic sciatic nerve compression group (DSNC, n = 5) and diabetic sciatic nerve decompression group (DSND, n = 20). The DSNC model was created by wrapping a silicone tube circumferentially around the nerve for 4 weeks, and then the DSND group accepted nerve decompression and was followed up to 12 weeks. The DSND group was equally divided into DSND 3 weeks (DSND3), 6 weeks (DSND6), 9 weeks (DSND9), and 12 weeks (DSND12) groups. Five rats were taken as normoglycemic control group (CR, n = 5), and another 5 rats as diabetic control group (DM, n = 5). The mechanical hyperalgesia of rats was detected by Semmes-Weinstein nylon monofilaments (SWMs) and by motor nerve conduction velocity (MNCV). These 2 physiological indicators and histology of sciatic nerves were compared among different groups. RESULTS: The SWM measurements improved toward normal values after decompression. The SWM value was significantly lower (more normal) in the DSNC groups than in the DSND group (P < 0.05). The MNCV was 53.7 ± 0.8 m/s in the CR group, whereas it was 28.4 ± 1.0 m/s in the DSNC group (P < 0.001). Six weeks after decompression, the MNCV was significantly faster than that in the DSNC group (P < 0.001). Histological examination demonstrated chronic nerve compression, which responded toward normal after decompression, but with degree of myelination never recovering to normal. CONCLUSIONS: Chronic compression of the diabetic sciatic nerve has measureable negative effects on sciatic nerve motor nerve function, associated with a decline of touch/pressure threshold and degeneration of myelin sheath and axon. Nerve decompression surgery can reverse these effects and partially restore nerve function.

Chronic Nerve Compression Accelerates the Progression of Diabetic Peripheral Neuropathy in a Rat Model: A Study of Gene Expression Profiling.

OBJECTIVE: This article investigates the role of chronic nerve compression in the progression of diabetic peripheral neuropathy (DPN) by gene expression profiling. METHODS: Chronic nerve compression was created in streptozotocin (STZ)-induced diabetic rats by wrapping a silicone tube around the sciatic nerve (SCN). Neurological deficits were evaluated using pain threshold test, motor nerve conduction velocity (MNCV), and histopathologic examination. Differentially expressed genes (DGEs) and metabolic processes associated with chronic nerve compression were analyzed. RESULTS: Significant changes in withdrawal threshold and MNCV were observed in diabetic rats 6 weeks after diabetes induction, and in DPN rats 4 weeks after diabetes induction. Histopathologic examination of the SCN in DPN rats presented typical changes of myelin degeneration in DPN. Function analyses of DEGs demonstrated that biological processes related to inflammatory response, extracellular matrix component, and synaptic transmission were upregulated after diabetes induction, and chronic nerve compression further enhanced those changes. While processes related to lipid and glucose metabolism, response to insulin, and apoptosis regulation were inhibited after diabetes induction, chronic nerve compression further enhanced these inhibitions. CONCLUSION: Our study suggests that additional silicone tube wrapping on the SCN of rat with diabetes closely mimics the course and pathologic findings of human DPN. Further studies are needed to verify the effectiveness of this rat model of DPN and elucidate the roles of the individual genes in the progression of DPN.

Free Vascularized Fibular Grafting Improves Vascularity Compared With Core Decompression in Femoral Head Osteonecrosis: A Randomized Clinical Trial.

BACKGROUND: Management of osteonecrosis of the femoral head remains challenging. Core decompression and free vascularized fibular grafting are commonly used surgical procedures for treatment of osteonecrosis of the femoral head. Few studies, however, have compared these two procedures in a randomized controlled study, in terms of improved vascularity of the femoral head, progression of disease, or hip scores. QUESTION/PURPOSES: (1) What is the effect of core decompression and fibular grafting on vascularity of the femoral head as measured by single-photon emission CT (SPECT)/CT? (2) Does one of these two methods lead to greater progression of Association Research Circulation Osseous (ARCO) stage as determined by serial MRI? (3) What is the relationship between the change in vascularity of the femoral head and hip function as measured by the Harris hip score (HHS) and progression to THA as an endpoint? METHODS: A randomized controlled trial was performed between June 2010 and October 2012 at Zhongshan Hospital, Fudan University. During the study period, 51 patients who presented with ARCO Stages I to IIIB bilateral osteonecrosis were potentially eligible for inclusion, and 33 patients were identified as meeting the inclusion criteria and offered enrollment and randomization. Six patients declined to participate at the time of randomization, leaving a final sample of 27 participants (54 hips). Bilateral hips of each patient were randomly assigned to surgical options: one side was treated with core decompression and the contralateral side was concurrently treated with fibular grafting. SPECT/CT examinations were performed to quantify radionuclide uptake to evaluate vascularity of the femoral head before treatment and at 6 and 36 months after surgery. With the numbers available, we found no differences between the groups regarding vascularity at baseline (64% ± 8% core decompression-treated hips versus 64% ± 7% in the fibular-grafted hips; 95% CI, -5% to 5%; p = 0.90). MR images of the hips were obtained before surgery and at 6, 12, 24, and 36 months postoperatively and staged based on the ARCO classification. All patients were assessed clinically before treatment and followed up at 6, 12, 18, 24, 30, and 36 months after treatment using the HHS. We considered a difference in the HHS of 10 as the minimal clinically important difference (MCID). Patient progression to THA was defined as the endpoint for followup. Six patients (22%) were lost to followup. RESULTS: By SPECT/CT analysis, decompression-treated hips had lower vascularity than fibular-grafted hips at 6 months (68 % ± 6% versus 95% ± 5%; mean difference, -27%; 95% CI, -32% to -23%; p < 0.001) and 36 months (57% ± 4% versus 91% ± 3%; mean difference, -34%; 95% CI, -37% to -32%; p < 0.001). MRI analysis showed no differences between decompression-treated hips and fibular-grafted hips regarding ARCO stage at 12 months (p = 0.306) and 24 months (p = 0.06). Progression of ARCO staging was more severe in the decompression group than the fibular grafting group at 36 months (p = 0.027). The mean HHS was lower in the decompression group than in the fibular grafting group throughout the followup period, although these differences were at or below the MCID of 10 points early on. However, by 18 months, the scores favored fibular grafting (72 ± 4 versus 84 ± 4; mean difference, -13; 95% CI, -15 to -7; p < 0.001), a finding that was maintained at 24, 30, and 36 months. We found no differences between decompression-treated hips and fibular-grafted hips regarding progression to THA at 36 months (two of 21; p = 0.893). CONCLUSIONS: Hips that underwent a vascularized fibular grafting procedure fared better than hips receiving core decompression as measured by improved vascularity and less progression of osteonecrosis as measured by ARCO staging. The mean HHS of the fibular-grafted hips was better than that of the decompression-treated hips during the entire postoperative period, but the differences were modest early on, and for the early postoperative period the differences were unlikely to have been clinically important; by 18 months after surgery, the differences probably were clinically important. The mid-term outcomes associated with vascularized fibular grafting seen in our patients are associated with improvements in femoral head vascularity and the potential for bone revitalization. LEVEL OF EVIDENCE: Level I, therapeutic study.

Different Recipient Vessels for Free Microsurgical Fibula Flaps in the Treatment of Avascular Necrosis of the Femoral Head: A Systematic Review and Meta-analysis.

BACKGROUND: Several recipient vessels can be used in free microsurgical fibula flaps (MFFs) for the treatment of avascular necrosis of the femoral head (ANFH). Few articles investigate the influence of different recipient vessels on outcomes of MFF for ANFH. METHODS: A comprehensive literature search of databases including PubMed-Medline, Ovid-Embase, and Cochrane Library was performed to collect the related studies. The Medical Subject Headings used were "femur head necrosis" and "bone transplantation." The relevant words in title or abstract included but not limited to "fibula flap," "fibular flap," "vascularized fibula," "vascularized fibular," "free fibula," "free fibular," "femoral head necrosis," "avascular necrosis of femoral head," and "ischemic necrosis of femoral head." The methodological index for nonrandomized studies was adopted for assessing the studies included in this review. RESULTS: Finally, 15 studies encompassing a total of 1267 patients (1603 hips) with ANFH were pooled in the overall analysis. Recipient vessels for MFF included the ascending branch of the lateral circumflex femoral artery and vein in 8 studies, descending branch of the lateral circumflex femoral artery and vein in 2 studies, second perforating branch of the deep femoral artery and vein in 4 studies, and inferior gluteal artery and vein in 1 study. Preoperative and postoperative average Harris hip score and pooled analyses of the rate of conversion, radiographic progression, and hip surgery-related complications showed no significant difference on the outcomes of MFF on ANFH between using different recipient vessels. CONCLUSIONS: Different recipient vessels did not affect outcomes in MFF procedures for ANFH. High-quality randomized controlled trials and prospective studies would be necessary to clarify reliable advantages and disadvantages between different recipient vessels. Until then, surgeons are justified in using ascending branch of the lateral circumflex femoral artery and vein, descending branch of the lateral circumflex femoral artery and vein, second perforating branch of the deep femoral artery and vein, and inferior gluteal artery and vein vessels according to care circumstances and customary practice.

Molecular Mechanism of the "Babysitter" Procedure for Nerve Regeneration and Muscle Preservation in Peripheral Nerve Repair in a Rat Model.

OBJECTIVE: To investigate the molecular mechanism of nerve "babysitter" for nerve regeneration and muscle preservation in peripheral nerve repair. METHODS: Eighty rats were equalized into 4 groups: peroneal nerve transected, group A received no treatment; group B underwent end-to-end repair; group C underwent end-to-side "babysitter" with donor epineurial window; group D underwent end-to-side "babysitter" with 40% donor neurectomy. During second-stage procedure, end-to-end neurorrhaphies were executed in groups A, C, and D. Expression of Insulin-like growth factor (IGF)-1 in spinal cord and IGF-1, TNF-like weak inducer of apoptosis (TWEAK), and Fn14 in anterior tibial muscles were evaluated by histopathology at 4-, 8-, 12-, and 24-week timepoints postoperatively. RESULTS: At 4 weeks, group D expressed comparable IGF-1 with group B, and greater value than groups A and C in spinal cord. By 24 weeks, groups B and D showed higher values than groups A and C. Insulin-like growth factor 1 in muscles were greater in groups C and D than in groups A and B at 4 weeks, and comparable in all groups at 24 weeks. At 4 weeks, immunoreactive scores of TWEAK were 9.00 ± 0, 3.00 ± 0, 6.75 ± 0.75, and 6.75 ± 0.75, respectively. No differences were noticed in all groups by 24 weeks. At 4 weeks, Fn14 were similar in groups A, C, and D, but lower in group B. Group D showed comparable Fn14 with groups B and C, but lower value than group A at 24 weeks. CONCLUSIONS: End-to-side nerve "babysitter" in peripheral nerve could promote fiber regeneration and muscle preservation by regulating expression of IGF-1 and TWEAK-Fn14. End-to-side "babysitter" with partial donor neurectomy could achieve comparable effects with end-to-end repair.

Efficacy and Safety of the Babysitter Procedure With Different Percentages of Partial Neurectomy.

BACKGROUND: After 2 months of denervation, the number of motor units in the muscle decreases; after 6 months of denervation, muscle atrophy and weakness are irreversible and successful nerve reconstruction does not generally restore function. The babysitter procedure was reported to successfully avoid muscle atrophy. One study found that the babysitter procedure with a 40% neurectomy was most suitable; however, the amount of donor nerve that can be borrowed for the babysitter procedure in peripheral nerve injury is unknown. METHOD: One hundred adult female Sprague-Dawley rats were used in this study. The rats were randomly allocated to 5 groups (groups A-E; n = 20 each). The rats underwent different surgeries based on their grouping. At 6, 12, 18, and 24 weeks after surgery, 5 rats in each group were selected for electrophysiology and muscle force tests. These rats were then killed, and the gastrocnemius and tibialis anterior muscles were harvested for weight measurement and cross-sectional muscle measurement. RESULT: The results of the effects on the peroneal nerves and tibialis anterior muscles after the babysitter procedure with 40% and 80% neurectomies showed that the functional ability of the recipient nerves was maintained and the muscle was effectively prevented from atrophy, whereas the 20% neurectomy and end-to-side procedures showed relatively poor performance. The results of the effects on the tibial nerve and gastrocnemius muscles after the babysitter procedure with 20% and 40% neurectomies showed that there was little effect on the donor nerve. By contrast, 80% neurectomy strongly and negatively affected the donor nerve. CONCLUSIONS: Our results indicate that the babysitter procedure using a donor nerve with a partial neurectomy of 40% was the best choice for effectively treating peripheral (peroneal) nerve injury in rats.

Surgical Decompression in the Treatment of Diabetic Peripheral Neuropathy: A Systematic Review and Meta-analysis.

Background Over the last decade, surgical decompression procedures have been commonly used in the treatment of diabetic peripheral neuropathy. However, the effectiveness of them remains to be proved. Methods A comprehensive literature search of databases including PubMed-Medline, Ovid-EMBASE, and Cochrane Library was performed to collect the related literatures. The Medical Subject Headings used were "diabetic neuropathy," "surgical decompression," and "outcomes." The methodological index for nonrandomized studies was adopted for assessing the studies included in this review. Analyses were performed with Review Manager (Version 5.3, Copenhagen: The Nordic Cochrane Centre, the Cochrane Collaboration, 2014). Results A total of 12 literatures (including 8 prospective and 4 retrospective) encompassing 1,825 patients with DPN were included in the final analysis. Only one literature was identified as a randomized controlled trial. The remaining 11 literatures were observational studies; 7 of them were classified as upper-extremity nerve decompression group and 4 of them were classified as lower-extremity nerve decompression group. Meta-analysis shows that Boston questionnaire symptom severity and functional status of upper extremities, and distal motor latency and sensory conduction velocity of median nerve of DPN patients are significantly improved after carpal tunnel release. Besides, visual analog scale and two-point discrimination are considered clinically and statistically significant in lower extremities after operation. Conclusions The findings from our review have shown the efficacy of surgical decompression procedures in relieving the neurologic symptoms and restoring the sensory deficits in DPN patients. As there are few high-quality randomized controlled trials or well-designed prospective studies, more data are needed to elucidate the role of surgical procedures for DPN treatment in the future.

Efficacy of the end-to-side neurorrhaphies with epineural window and partial donor neurectomy in peripheral nerve repair: an experimental study in rats.

BACKGROUND: End-to-side (ETS) neurorrhaphy was a useful tool in peripheral nerve repair and "baby-sitter" procedure. The study was designed to evaluate the long-term efficacy of ETS with epineurial window and 40% partial donor neurectomy in rats. MATERIALS AND METHODS: A total of 60 Lewis rats were divided into three groups (n = 20, each group): following peroneal nerve transection, rats in Group A underwent end-to-end neurorrhaphy; rats in Group B underwent ETS neurorrhaphy of the distal peroneal nerve stump to an epineurial window on the tibial nerve; and rats in Group C underwent ETS neurorrhaphy of the distal peroneal nerve stump to the tibial nerve with 40% partial neurectomy. At 6, 12, 18, and 24 weeks after surgery, electrophysiology, muscle tension, myelinated fiber regeneration, cross-sectional area of muscular fiber, and muscle weight were analyzed. RESULTS: Histology exhibited apparently increased number and size of myelinated fibers in peroneal nerves in Group C, compared with those in Group B. More superior recovery was demonstrated in the electrophysiology and axon regeneration of the peroneal nerves, as well as the maintenance of muscle force, wet weight, and fiber size of the anterior tibial muscles in Group C than those in Group B. CONCLUSION: ETS neurorrhaphy with partial donor neurectomy can achieve higher efficacy in functional and structural recovery of the recipient system. This study provides the evidence of long-term follow-up for the further investigation of ETS neurorrhaphies with different modalities in peripheral nerve repair and in "baby-sitter" procedure.

[Nerve classification with hyperspectral imaging technology].

In surgical nerve repair surgery, the identification of nerve fascicles is a key to a good repair of their broken end. Some of the existing nerve fascicles identification method are not ideal. Hyperspectral imaging (HSI) technology provides information of images and spectra of biological tissue at the same time. It can supply a qualitative, quantitative and positioning description of the test objectives, and identify different biological tissues by biochemical characteristic difference, and classify and position these tissues in the image. Compared to other medical imaging technology, this techriology has unique advantages. In this study, the hyperspectral imaging technology is used in the identification and classification of the nerve fascicles by the spectral characteristics of different nerve fascicles, and in determining the orientation of the nerve fascicles in the image by the image spectral information in order to better help surgical personnel to carry out the nerve repair surgery. The significance of this paper is: the first to propose a new method of identification and location of the nerve fascicles and assist surgical staff to improve the efficacy of nerve repair; the second to reserve hyperspectral imaging techniques used in qualitative and quantitative and orientation research combined with biological organization, and speed up the molecular hyperspectral imaging technology to the practical stage.

Association between cytochrome P450 2C9 gene polymorphisms and colorectal cancer susceptibility: evidence from 16 case-control studies.

Previous epidemiological studies have evaluated the association between common variations of cytochrome P450 (CYP)2C9 (430C>T and 1075A>C) and the risk of colorectal cancer (CRC) with conflicting results. To derive a more precise estimation of the relationship between these CYP2C9 polymorphisms and CRC, a meta-analysis was performed. PubMed, Embase, CNKI, and Web of Science databases were searched. A total of 16 studies including 9,463 cases and 11,416 controls were identified. Potential sources of heterogeneity including ethnicity, sample size of study, genotyping method, diagnostic criteria, and outcome were systematically assessed. Overall, the summary odds ratio of 430T variant for CRC was 0.92 (95% confidence interval (CI) 0.86-0.98; P = 0.012) and 1.39 (95% CI 1.07-1.81; P = 0.013) for colorectal adenomas (CRAs). As for CYP2C9 1075A>C polymorphism, no significant results were observed in overall and subgroup analysis. There was no evidence of publication bias. In conclusion, there is evidence to indicate a significant association between CYP2C9 430C>T polymorphism and CRC/CRA risk.

The prevention effect of poly (L-glutamic acid)/chitosan on spinal epidural fibrosis and peridural adhesion in the post-laminectomy rabbit model.

PURPOSE: Spinal epidural fibrosis and adhesion are implicated as one of the key factors of failed back surgery syndrome, which may cause dura mater compression or peridural tethering, resulting in persistent backache and leg pain. Various materials or drugs have been used to inhibit formation of epidural fibrosis and reduce the compressive effect on neural structures. Nevertheless, the effects are not satisfied. In this study, we investigated the prevention effect of poly (L-glutamic acid)/chitosan (PLGA/CS) barrier on epidural fibrosis developing post-laminectomy in a rabbit model. METHODS: Sixteen rabbits were divided randomly into two equal groups: group A (experimental group, n = 8) and group B (non-treatment group, n = 8). In both groups, total L5-6 laminectomy was performed; further both ligamentum flavum and epidural fat were removed gently. In experimental group, the laminectomy sites were treated with PLGA/CS barriers, while no additional treatment was received in non-treatment group. At 1, 12 and 24 weeks post-surgery, the animals were subjected to magnetic resonance imaging (MRI) evaluation. Following last MRI examination, all rabbits were sacrificed and their spinal columns were totally removed for further macroscopic and histological evaluation. RESULTS: MRI showed that rabbits treated with PLGA/CS barrier at 12 and 24 weeks post-surgery had less epidural fibrosis or scar tissue, peridural adhesion, foreign body reaction and low pressure of spinal cord in comparison with the non-treatment group. In consistence with the radiographic results, macroscopic analysis and histological examination showed that the amount of scar tissue and the extent of epidural adhesion decreased significantly in experimental groups. Concerning the fibroblast density evaluated, the scores were significantly lower in experimental group compared with those in non-treatment group. CONCLUSION: The results of our study demonstrate that PLGA/CS barrier is effective in inhibiting epidural fibrosis and peridural adhesions in post-laminectomy rabbit model.

Changes of the donor nerve in end-to-side neurorrhaphies with epineurial window and partial neurectomy: a long-term evaluation in the rat model.

End-to-side (ETS) neurorrhaphy has been applied in the repair of peripheral nerve injuries and in babysitter procedures. However, the long-term changes of donor nerve and muscle after ETS remain unknown. This study was designed to investigate long-term changes in donor nerve and muscle in a rat model. Sixty Lewis rats were equally allocated into three groups of 20 rats. The peroneal nerve was divided. In Group A, end-to-end (ETE) neurorrhaphy was performed. In Group B, ETS was performed to an epineurial window on the tibial nerve. In Group C, ETS was performed to the tibial nerve with 40% partial neurectomy. The following data were obtained at 6, 12, 18, and 24 weeks postoperatively: latency delaying rate (LDR), amplitude recovery rate (ARR), myelinated fiber counts, muscle force and weight, and cross-sectional area of gastrocnemius muscle fibers. The results showed no significant changes of the donor nerve and muscle in Group B. Nerve regeneration was found in the peroneal nerve, and myelinated fiber number was significantly decreased when compared to the nerve with ETE. In Group C, the myelinated axon number in the peroneal nerve was equivalent to the level in ETE repair. However, function and structure of the donor nerve and muscle were significantly impaired in the early postoperative period. Nonetheless, full recovery was observed 24 weeks after surgery. Both ETS with epineurial window and 40% donor nerve neurectomy showed reinnervation of the recipient nerve without structural and functional changes of the donor system in a long-term follow-up. Partial neurectomy may promote recipient nerve regeneration, but at the cost of donor neuromuscular compromises in the early postoperative period. This study provides long-term evidence for further investigation of ETS in peripheral nerve repair and in babysitter procedures.

AOTF based molecular hyperspectral imaging system and its applications on nerve morphometry.

The neuroanatomical morphology of nerve fibers is an important description for understanding the pathological aspects of nerves. Different from the traditional automatic nerve morphometry methods, a molecular hyperspectral imaging system based on an acousto-optic tunable filter (AOTF) was developed and used to identify unstained nerve histological sections. The hardware, software, and system performance of the imaging system are presented and discussed. The gray correction coefficient was used to calibrate the system's spectral response and to remove the effects of noises and artifacts. A spatial-spectral kernel-based approach through the support vector machine formulation was proposed to identify nerve fibers. This algorithm can jointly use both the spatial and spectral information of molecular hyperspectral images for segmentation. Then, the morphological parameters such as fiber diameter, axon diameter, myelin sheath thickness, fiber area, and g-ratio were calculated and evaluated. Experimental results show that the hyperspectral-based method has the potential to recognize and measure the nerve fiber more accurately than traditional methods.

An Uncommon Case of Necrotizing Fasciitis and Septic Shock Caused by Vibrio vulnificus Infection-Related Freshwater Shrimp Stung.

Vibrio vulnificus is a deadly marine pathogen that can cause necrotizing fasciitis, septic shock, and even death in severe cases. The relatively low incidence and atypical early-stage symptoms may hinder many physicians from carrying out surgical intervention effectively, thus leading to an increase of mortality in infected patients. This article reported a patient who developed necrotizing fasciitis and septic shock after the exposure to freshwater shrimp stabbed on the limb. By reviewing and analyzing previous studies, it was found out that the timing of surgery could have a significant impact on the patients for their necrotizing fasciitis caused by Vibrio vulnificus infection. The mortality among patients undergoing early-stage surgical treatment (≤12 hours from the time of admission) was significantly lower than that of patients undergoing late surgical treatment (>12 hours).

Paradoxical Changes of Cutaneous Microcirculation and Sympathetic Fibers of Rat Hind Limbs after Sciatic Nerve Compression.

BACKGROUND: Recent studies show evidence that surgical nerve decompression could improve cutaneous blood flow (CBF), which might benefit ulcer healing. However, the change of CBF and sympathetic fibers after nerve compression is poorly understood. In the current study, a unilateral sciatic nerve compression model was created in Sprague-Dawley rats. METHODS: A laser Doppler imaging system was applied to assess the CBF of the regions below the ankles. Immunohistochemistry and transmission electron microscopy were used to investigate the histopathologic changes of sympathetic fibers in sciatic nerve samples. RESULTS: Laser Doppler imaging revealed decreased CBF of both the lesional limb and the contralesional limb, which occurred earlier in the lesional side, indicating an enhanced sympathetic tone on vasomotor function. Intraneural density of sympathetic fibers decreased on both sides and the ultrastructure of unmyelinated fibers of both sides degenerated in a nonsynchronized manner. CONCLUSIONS: The study revealed nonsynchronized reduced CBF of bilateral hind limbs with paradoxically degenerated and diminished sympathetic fibers in bilateral sciatic nerves after unilateral sciatic nerve compression. These results may validate the importance of and broaden the indications for surgical nerve decompression in preventing or treating foot ulcers.

Finger pulp reconstruction with free flaps from the upper extremity.

Although never exceeding a few square centimeters, finger pulp defects are reconstructive challenges due to their special requirements and lack of neighboring tissue reserve. Local flaps are the common choice in the management of this injury. However, the development of microsurgery and clinical practice have greatly boosted the application of different free flaps for finger pulp reconstruction with excellent results, especially when local flaps are unsuitable or impossible for the coverage of large pulp defects. These flaps are all located in the same operation field and can be performed under one tourniquet; therefore, they are more convenient with better patients' compliance in clinical setting. Nonetheless, there is still no consensus about which type of these flaps should be preferred among various finger pulp reconstructive options. In this article, we attempt to review articles describing finger pulp reconstruction using free flaps from the upper extremity from the literature. We summarize the clinical applications of these free flaps and detail their advantages and drawbacks, respectively. The algorithm of flap selection for finger pulp reconstruction based on our experience and literature review is also discussed.

Individualized surgical treatment for patients with tumours of the cervicothoracic junction.

OBJECTIVES: The cervicothoracic junction is a special section that connects the neck, thoracic cavity, mediastinum and axilla. Tumours in the region often invade or compress surrounding tissues and organs, which makes the surgical treatment difficult. METHODS: A retrospective analysis involving 69 patients with tumours at the cervicothoracic junction. Clinical data with regard to manifestation, surgical approach, resection degree, outcome and pathological types were collected. RESULTS: A total of 48 cases of asymptomatic patients and 21 cases of patients with ≥1 clinical manifestation were enrolled in the study. Twenty-seven patients received radical resection with video-assisted thoracoscopic surgery. Anterior approach was the predominant treatment method in open surgery (25 cases, 36.2%), while the anterolateral approach was used in 8 cases (6 cases of hemiclamshell incisions and 2 cases of trap-door incisions). In addition, we observed 1 case of posterior approach, 2 cases of posterolateral approach and 1 case of supraclavicular approach combined with posterolateral approach. Pathological examination results revealed 67 cases of radical resection and 2 cases of microscopic residual. Neurilemmoma was the most widespread pathological type (30 cases, 43.5%), followed by tumour originating from fibrous tissues (5 cases, 7.2%). A 3-year overall survival rate of the 69 patients was 89.9%, while a 5-year overall survival rate was 85.5%. CONCLUSIONS: Tumours associated with the cervicothoracic junction are characterized by their unique location, complex anatomy and various histopathological subtypes. An individualized approach during surgery enhances safety and standardized of treatments for patients with tumours located at the cervicothoracic junction.