Surgical treatment of distal radius fractures: impact on forearm rotation in non-elderly patients.

Forearm rotation restriction (FRR) is common after surgery for distal radius fractures (DRFs). The aim of the current study was to investigate the effect of DRFs on forearm rotation. This retrospective study reviewed patients with DRFs who underwent surgical treatment from January 2019 to December 2021. The patients' basic data and radiographic parameters were analyzed. Forearm rotation, including pronation and supination, was assessed using a standard goniometer. The Patient-Rated Wrist Evaluation (PRWE) score was evaluated, and the incidence of FRR at the 6-month follow-up was recorded. Univariate and multivariate logistic regression analyses were performed to identify risk factors correlated with FRR. A total of 127 patients with DRFs were included in this study. After surgery, 46 cases were considered to have FRR, with a rate of 36.2%, while the remaining 81 cases (63.8%) did not have FRR. The PRWE scores were 22.8 ± 5.2 and 17.9 ± 4.2 in the FRR group and non-FRR group, respectively, and the difference was statistically significant (P < 0.05). Multivariate analysis showed that the involvement of the sigmoid notch (OR, 2.88; 95% CI 1.49-5.56), post-operative volar tilt < 0° (OR, 2.16; 95% CI 1.34-3.50), and post-operative ulnar variance > 0 mm (OR, 1.37; 95% CI 1.06-1.78) were independently associated with the incidence of FRR. The FRR is associated with an increased PRWE score and may have had some impact on the patient's daily life. Fractures involving the sigmoid notch, dorsal angulation, and radial shortening deformity were found to be correlated with the incidence of FRR. Preoperative risk notification and intraoperative preventive measures are necessary for these patients.

Preparation and Characterization of Conductive/Self-Healing Resin Nanocomposites Based on Tetrafunctional Furan-Functionalized Aniline Trimer Modified Graphene.

The nanocomposites with reversible cross-linking covalent bonds were prepared by reacting furfurylamine (FA)-modified diglycidyl ether of bisphenol A (DGEBA) and furfuryl-functionalized aniline trimer-modified graphene (TFAT-G) with bismaleimide (BMI) via the Diels-Alder (DA) reaction. The successful synthesis of the TFAT modifier is confirmed by nuclear magnetic resonance (NMR) hydrogen spectroscopy and IR spectroscopy tests. The structure and properties of TFAT-G epoxy nanocomposites are characterized by scanning electron microscopy (SEM), differential scanning calorimeter (DSC), tensile, and resistivity. The results show that TFAT-G was uniformly dispersed in the resin, and 1 wt% TFAT-G composites increased to 233% for tensile strength, 63% for elongation at break, 66% for modulus, and 7.8 °C for Tg. In addition, the addition of unmodified graphene degrades the mechanical properties of the composite. Overall, the graphene/self-healing resin nanocomposites have both good self-healing function and electrical conductivity by adding 1 wt% modified graphene; this allows for the maintenance of the original 83% strength and 89% electrical conductivity after one cycle of heating repair.

Parametric Study on Low-Velocity Impact (LVI) Damage and Compression after Impact (CAI) Strength of Composite Laminates.

A full-scale model for predicting low-velocity impact (LVI) damage and compression after impact (CAI) strength was established based on a subroutine of the material constitutive relationship and the cohesive elements. The dynamic responses of the laminate under impact load and damage propagation under a compressive load were presented. The influences of impact energy and ply thickness on the impact damage and the CAI strength were predicted. The predicted results were compared with the experimental ones. It is shown that the predicted value of the CAI strength is in good agreement with the experimental result. As the impact energy reaches a certain value, the CAI strength no longer decreases with the increase in the impact energy. Decreasing the ply thickness can effectively improve the damage resistance and CAI strength.

Electrospun Polycaprolactone (PCL)-Amnion Nanofibrous Membrane Promotes Nerve Regeneration and Prevents Fibrosis in a Rat Sciatic Nerve Transection Model.

Functional recovery after peripheral nerve injury repair is typically unsatisfactory. An anastomotically poor microenvironment and scarring at the repair site are important factors impeding nerve regeneration. In this study, an electrospun poly-e-caprolactone (PCL)-amnion nanofibrous membrane comprising an amnion membrane and nonwoven electrospun PCL was used to wrap the sciatic nerve repair site in the rat model of a sciatic nerve transection. The effect of the PCL-amnion nanofibrous membrane on improving nerve regeneration and preventing scarring at the repair site was evaluated by expression of the inflammatory cytokine, sciatic functional index (SFI), electrophysiology, and histological analyses. Four weeks after repair, the degree of nerve adhesion, collagen deposition, and intraneural macrophage invasion of the PCL-amnion nanofibrous membrane group were significantly decreased compared with those of the Control group. Moreover, the PCL-amnion nanofibrous membrane decreased the expression of pro-inflammatory cytokines such as interleukin(IL)-6, Tumor Necrosis Factor(TNF)-a and the number of pro-inflammatory M1 macrophages, and increased the expression of anti-inflammatory cytokine such as IL-10, IL-13 and anti-inflammatory M2 macrophages. At 16 weeks, the PCL-amnion nanofibrous membrane improved functional recovery, including promoting nerve Schwann cell proliferation, axon regeneration, and reducing the time of muscle denervation. In summary, the PCL-amnion nanofibrous membrane effectively improved nerve regeneration and prevent fibrosis after nerve repair, which has good clinical application prospect for tissue repair.

Electrospun Polycaprolactone (PCL)-Amnion Nanofibrous Membrane Promotes Nerve Repair after Neurolysis.

Peripheral nerve adhesion after neurolysis leads to nerve dysfunction, limiting nerve regeneration and functional recovery. We previously developed an electrospun polycaprolactone (PCL)-amnion nanofibrous membrane for preventing adhesion formation. In this study, we investigated the effect of protective nerve wrapping and promoting nerve regeneration in a rat sciatic nerve compression model. A total of 96 SD rats after sciatic nerve chronic compression were randomly divided into three groups: the PCL-amniotic group, in which nerves were wrapped with a PCL-amniotic membrane for treatment; the chitosan group, in which nerves were wrapped with a clinically used chitosan hydrogel; the control group, which involved neurolysis alone without treatment. Twelve weeks postoperatively, the nerve regeneration was evaluated by general and ultrastructure observation, as well as the expressions of neuronal regeneration and inflammatory reaction biomarkers. The nerve functions were assessed with gastrocnemius muscle measurement, hot-plate test, and walking track analysis. Compared with the chitosan hydrogel, the PCL-amnion nanofibrous membrane significantly reduced peripheral nerve adhesion and promoted nerve regeneration. The morphological properties of axons in the nerve wrap group were preserved. Intraneural macrophage invasion, as assessed by the number of CD68-positive cells, was less severe in the PCL-amnion group than in the other groups. Additionally, the gastrocnemius muscle weight and muscle bundle area were significantly higher in the PCL-amnion group than those in the chitosan group. The abilities of sense and movement of the rats in the PCL-amnion group were significantly improved compared to the other groups. In summary, electrospun PCL-amnion nanofibrous membranes effectively prevented post-neurolysis peripheral nerves from developing adhesion, whereas promoted nerve repair and regeneration, which make PCL-amnion nanofibrous membranes a promising biomaterial for clinical application.

Simplified Analytical Model for Predicting Neutral Cross-Section Position of Lenticular Deployable Composite Boom in Tensile Deformation.

Foldable and deployable flexible composite thin-walled structures have the characteristics of light weight, excellent mechanical properties and large deformation ability, which means they have good application prospects in the aerospace field. In this paper, a simplified theoretical model for predicting the position of the neutral section of a lenticular deployable composite boom (DCB) in tensile deformation is proposed. The three-dimensional lenticular DCB is simplified as a two-dimensional spring system and a rigid rod, distributed in parallel along the length direction. The position of the neutral cross-section can be determined by solving the balance equations and geometric relations. In order to verify the validity of the theoretical model, a finite element model of the tensile deformation of a lenticular DCB was established. The theoretical prediction results were compared with the finite element calculation results, and the two results were in good agreement.

Correction: Electrospun polycaprolactone (PCL)-amnion nanofibrous membrane prevents adhesions and promotes nerve repair in a rat model of sciatic nerve compression.

[This corrects the article DOI: 10.1371/journal.pone.0244301.].

Electrospun polycaprolactone (PCL)-amnion nanofibrous membrane prevents adhesions and promotes nerve repair in a rat model of sciatic nerve compression.

Adhesion and scarring after neural surgery are detrimental to nerve regeneration and functional recovery. Amniotic membranes have been used in tissue repair due to their immunogenicity and richness in cytokines. In this study, an electrospun polycaprolactone (PCL)-amnion nanofibrous membrane was prepared for the treatment of sciatic nerve compression in a rat model. The effects of the PCL-amnion nanofibrous membrane on the prevention of adhesion formation and nerve regeneration were evaluated using electrophysiology and histological analyses. Compared with the medical chitosan hydrogel dressing, the PCL-amnion nanofibrous membrane significantly reduced peripheral nerve adhesion and promoted the rapid recovery of nerve conduction. Moreover, the immunohistochemical analysis identified more Schwann cells and less pro-inflammatory M1 macrophages in the PCL-amnion group. Western blot and RT-PCR results showed that the expression levels of type-Ⅰ and Ⅲ collagen in the PCL-treated rats were half of those in the control group after 12 weeks, while the expression level of nerve growth factor was approximately 3.5 times that found in the rats treated with medical chitosan hydrogel. In summary, electrospun PCL-amnion nanofibrous membranes can effectively reduce adhesion after neural surgery and promote nerve repair and regeneration. The long-term retention in vivo and sustained release of cytokines make PCL-amnion a promising biomaterial for clinical application.

Regulation of ERK1/2 and SMAD2/3 Pathways by Using Multi-Layered Electrospun PCL-Amnion Nanofibrous Membranes for the Prevention of Post-Surgical Tendon Adhesion.

BACKGROUND: Adhesion after tendon injury is a common complication in clinical practice. The lack of effective prevention mechanisms seriously affects the functional rehabilitation of patients. This research aimed to optimise the amniotic membrane and explain the mechanism of tendon-amniotic membrane by imitating the tendon sheath to construct a multilayer electrospun polycaprolactone (PCL) nanofibre membrane. MATERIALS AND METHODS: Fresh amnions were subjected to freezing and vacuum drying. The two surfaces of freeze-dried amnions were coated with PCL nanofibres by electrospinning, thereby forming a multilayer composite membrane and constructing a growth factor-sustained release system conforming to the tendon-healing cycle. The new materials were characterised, and the biological effects on tenocytes and fibroblasts were evaluated. The tendon injury model of New Zealand rabbits was constructed to observe the effects on tendon adhesion and healing. RESULTS: After freezing and vacuum drying, fresh amnions were found to effectively remove most of the cell components but retained the active components TGF-ß1, bFGF, VEGF, and PDGF, as well as the fibrous reticular structure of the basement membrane. After coating with PCL nanofibres, a composite membrane mimicking the structure of the tendon sheath was constructed, thereby strengthening the tensile strength of the amnion. By up-regulating the phosphorylation of ERK1/2 and SMAD2/3, the adhesion and proliferation of tenocytes and fibroblasts were promoted, and collagen synthesis was enhanced. In the rabbit tendon repair model, the composite membrane effectively isolated the exogenous adhesion tissue and promoted endogenous tendon healing. CONCLUSION: The composite membrane mimicking the structure of tendon sheath effectively isolated the exogenous adhesion tissue and achieved good tendon slip. By slowly releasing the growth factors TGF-ß1, bFGF, VEGF and PDGF, the ERK1/2 and SMAD2/3 pathways were regulated. Consequently, endogenous tendon healing was promoted. This strategy can alternatively address the clinical problem of tendon adhesion.

Metformin Enhances Functional Recovery of Peripheral Nerve in Rats with Sciatic Nerve Crush Injury.

BACKGROUND The aim of this study was to explore the effect of metformin by inducing autophagy for enhancing functional recovery of peripheral nerve in rats with sciatic nerve crush injury. MATERIAL AND METHODS Autophagy was determined by electron microscopy, immunofluorescence, and Western blot analysis. Motor function recovery was studied by the footprint intensity method. Axonal growth and regeneration were detected through Western blot while axonal remyelination was analysed through immunocytochemistry. Sensory and functional recovery were assessed by reflexive motor function analysis. RESULTS The present study deciphered the role of autophagy induction by metformin in motor functions and peripheral nerve regeneration following sciatic nerve crush injury in rats. The process was detected by measuring autophagosomes and the expression of microtubule-associated protein 1A/1B-light chain 3 upon metformin treatment of sciatic nerve crush-injured rats. Neurobehavioral recovery by metformin was tested by CatWalk gait analysis, and we quantified expression of myelin basic protein MBP and neurofilament NF200 at the damage sight by immunoblotting. In metformin-treated injured rats, autophagy was upregulated, by which the number of dead cells was decreased. Motor function was also recovered after metformin treatment, which was accompanied by upregulation of MBP and NF200 through autophagy induction. Surprisingly, the motor regenerative capability was reduced by treatment with 3-methyl adenine (an autophagy inhibitor) in nerve-injured rats. CONCLUSIONS Our study revealed that pharmacological induction of autophagy has an important and active role in the regeneration of nerve and motor function regain.

Repair of thumb defect by using the toenail flap: biomechanical analysis of donor foot-a retrospective cohort study.

BACKGROUND: The thumb accounts for 50% of the total hand function. This study reports the functional outcomes and complications of people with traumatic thumb amputations who underwent toe-to-thumb reconstruction. METHODS: From January 2013 to January 2018, 29 patients with second-degree thumb defect underwent thumb reconstruction with distal phalangeal braided toenail flap. The footscan foot pressure gait analysis system was used to measure the index changes of the same foot before and after 1, 3 and 6 months. The contact area, peak pressure, impulse value, contact time of each gait phase, centre of gravity coordinate and foot balance were analysed statistically. RESULTS: Twenty-nine cases of thumb reconstruction recovered well. After following up for 6-15 months, the appearance of the reconstructed thumb was close to normal, and the sensation was restored to S3+. The two-point discrimination was 6-8 mm, and the function of the thumb was good. The function of the donor foot was well restored, and no skin ulceration, pain and claudication were noted during walking. Compared with that before the operation, the biomechanical indices of the donor foot were basically restored to normal 6 months after the operation. Only the stress and impulse values of the third metatarsal head were significantly increased, forming a stress concentration area centred on the third metatarsal head. CONCLUSIONS: This study confirmed that the toenail flap with distal phalangeal bone restored the second-degree thumb defect without destroying the main functional structure of the sole. The biomechanical indices of the donor foot were basically restored to normal 6 months after the operation. Only the stress concentration area centred on the third metatarsal head, and the pain on the forefoot was induced after the operation. Discomfort, callus formation, metatarsal fasciitis, etc., can lead to fatigue fracture of the third metatarsal bone in severe cases, which requires further follow-up and observation. TRIAL REGISTRATION: Clinicaltrials.gov , NCT03879941; registered on 10 March 2019, retrospectively.

The comparison of limited-incision versus standard-incision in treatment of carpal tunnel syndrome: A meta-analysis of randomized controlled trials.

BACKGROUND: Carpal tunnel syndrome is a common compressive neuropathy of the median nerve. Compared with standard release, the efficacy, safety, and postoperative complications of limited carpal tunnel release remain controversial. The purpose of this study was to compare the effects of the 2 treatments. METHODS: The English-language literature was searched using MEDLINE, Web of Science, and Embase. Randomized controlled trials that compared standard and limited incision for carpal tunnel release were included in the meta-analysis. Strength, interval to return to activities, the rate of adverse events, effectiveness, and operative time were compared. RESULTS: Thirteen randomized controlled trials (RCTs) containing 1020 patients were included. Limited incision treated patients showed better early recovery of grip strength (mean difference [MD], 4.25 [0.86-7.65]; P = .01) and pinch strength (MD, 1.37 [0.24-2.51]; P = .02) but no advantage after more than 6 months. Patients treated with limited incision showed an earlier return to activities (MD,-8.80 [-9.21 to -8.39]; P < .01) and reduced operative time (standardized mean difference [SMD], -1.68 [-3.24 to-0.12]; P = .04). The rate of adverse event was significantly higher in standard group compared with that in limited group (risk ratio [RR] 0.61, 95% CI 0.38-0.96, P = .03). CONCLUSIONS: Limited incision release allows us to return to activities early, reduces operative time, decreases rate of adverse events, and improves strength during the early postoperative period. Results at 6 months or longer are similar according to current data. However, the results of this meta-analysis should be interpreted with caution due to heterogeneity amongst the included studies.

Biological Amnion Prevents Flexor Tendon Adhesion in Zone II: A Controlled, Multicentre Clinical Trial.

INTRODUCTION: Tendon adhesion to surrounding tissues is the most common complication reported after tendon repair. To date, effective solutions to prevent tendon injury are still lacking. MATERIALS AND METHODS: A total of 89 patients with flexor tendon injury in zone II were recruited. The patients were divided into a control group, a poly-DL-lactic acid (PDLLA) group, and an amnion group according to the different tendon treatments applied. The control group was not subjected to other treatments. PDLLA and bioamniotic membranes were, respectively, used to wrap broken ends in the PDLLA and amnion membrane groups. The patients were followed at 1, 2, 3, 6, and 12 months after surgery and the ranges of active flexion and extension lag in the proximal and distal interphalangeal joints were evaluated. RESULTS: The means of total active ranges of motion of the interphalangeal joints (excluding rupture cases) in the PDLLA and amnion groups did not significantly differ between each other but significantly differed from that of the control group. Statistical analysis showed a significant difference in the clinical grades of the outcomes among the control, PDLLA, and amnion groups. The incidence of complications in the control and PDLLA groups was found to be significantly higher than that in the amniotic membrane group; no significant difference was observed between the control and PDLLA groups. CONCLUSION: In this study, freeze-dried amniotic membrane transplantation was applied to promote healing of the flexor tendon in zone II and prevent adhesion. This technique presents a new method to solve the issue of tendon adhesion after repair. CLINICAL TRIAL REGISTRATION: The trial was registered by identifier ChiCTR1900021769.

Platelet-rich plasma injection for the treatment of chronic Achilles tendinopathy: A meta-analysis.

BACKGROUND: Platelet-rich plasma (PRP) is used as an alternative therapy to reduce pain and improve functional restoration in patients with Achilles tendinopathy (AT). We evaluated the current evidence for the efficacy of PRP as a treatment for chronic AT. METHODS: The PubMed, Embase, Web of Science, and The Cochrane Library databases were searched for articles on randomized controlled trials (RCTs) that compared the efficacy of PRP with that of with placebo injections plus eccentric training as treatment for AT. The articles were uploaded over the establishment of the databases to May 01, 2018. The Cochrane risk of bias (ROB) tool was used to assess methodological quality. Outcome measurements included the Victorian Institute of Sports Assessment-Achilles (VISA-A), visual analog scale (VAS) and Achilles tendon thickness. Statistical analysis was performed with RevMan 5.3.5 software. RESULTS: Five RCTs (n = 189) were included in this meta-analysis. Significant differences in the VISA-A were not observed between the PRP and placebo groups after 12 weeks [standardized mean difference (SMD) = 0.2, 95% confidence interval (95% CI): 0.36 to 0.76, I = 71%], 24 weeks (SMD = 0.77, 95% CI: -0.10-1.65, I = 85%) and 1 year (SMD = 0.83, 95% CI: -0.76-2.42, I = 72%) of treatment. However, PRP exhibited better efficacy than the placebo treatment after 6 weeks (SMD = 0.46, 95% CI: 0.15-0.77, I = 34%). Two studies included VAS scores and tendon thickness. VAS scores after 6 weeks (SMD = 1.35, 95% CI: -0.1.04-3.74, I = 93%) and 24 weeks (SMD = 1.48, 95% CI: -0.1.59-4.55, I = 95%) were not significantly different. However, VAS scores at the 12th week (SMD = 1.10, 95% CI: 0.53-1.68, I = 83%) and tendon thickness (SMD = 1.51, 95% CI: 0.39-2.63, I = 53%) were significantly different. CONCLUSION: PRP injection around the Achilles tendon is an option for the treatment of chronic AT. Limited evidence supports the conclusion that PRP is not superior to placebo treatment. These results still require verification by a large number of well designed, heterogeneous RCT studies.

Is correction of segmental kyphosis necessary in single-level anterior cervical fusion surgery? An observational study.

BACKGROUND: This study was conducted to determine whether sagittal lordotic alignment and clinical outcomes could be improved by the correction of segmental kyphosis after single-level anterior cervical discectomy and fusion (ACDF) surgery. PATIENTS AND METHODS: We retrospectively reviewed patients who underwent single-level ACDF surgery in our hospital between January 2014 and February 2017. Basic characteristics of patients included age at surgery, gender, diagnosis, duration of symptoms, and location of target level. Pre- and postoperative radiographs at the 6-month follow-up were used to evaluate the following parameters, such as segmental angle, C2-C7 angle, T1 slope, and C2-C7 sagittal vertical axis (SVA). Postoperative clinical outcomes were assessed by the Neck Disability Index and VAS. According to the segmental angle of postoperative radiographs, patients were divided into noncorrection group and correction group. RESULTS: A total of 181 patients (99 males and 82 females) were analyzed in our study. There were 32 patients in the noncorrection group and 149 patients in the correction group. There was no significant difference in demographic and clinical data between the two groups before surgery. However, patients in the correction group showed larger C2-C7 angle and lower C2-C7 SVA after surgery in comparison with those in the noncorrection group. Besides, changes in the segmental angle were positively correlated with changes in C2-C7 angle and negatively correlated with changes in C2-C7 SVA. CONCLUSION: Surgical correction of segmental kyphosis in single-level cervical surgery contributed to balanced cervical alignment in comparison with those without satisfactory correction. However, we could not demonstrate that the correction of segmental alignment is associated with a better recovery in clinical outcomes.

Risk factors associated with clinical adjacent segment pathology following multi-level cervical fusion surgery.

Few clinical studies investigate risk factors associated with clinical adjacent segment pathology (CASP) following multi-level cervical fusion surgery. The aim is to record the incidence of postoperative CASP in patients after at least 2 years' follow-up and to identify possible risk factors that may be associated with the CASP after multi-level cervical surgery.We retrospectively reviewed patients who underwent multi-level cervical surgery in our hospital from January 2004 to February 2016. All patients underwent more than 2 years' follow-up. The diagnosis of CASP is according to clinical symptoms as well as image findings. Potential risk factors were collected from demographic data and radiographic images.A total of 301 patients after multi-level cervical surgery were analyzed. During follow-up, 28 patients (9.3%) were diagnosed as having CASP. Among these patients, 7 showed symptoms of CASP within 3 years after surgery, 6 showed symptoms between 3 and 5 years, 14 showed symptoms between 5 and 10 years, and the last one showed symptoms more than 10 years later. In the multivariate analysis, degeneration of adjacent segment (OR, 1.592; 95% CI, 1.113-2.277), decreased Cobb angle in fused vertebrae (OR, 2.113; 95% CI, 1.338-3.334) and decreased Cobb angle in cervical spine (OR, 1.896; 95% CI, 1.246-2.886) were correlated with the incidence of CASP during follow-up.The incidence of CASP following multi-level cervical surgery was 9.3% with a mean of about 70 months' follow-up. Patients with preoperative degeneration of adjacent segment and postoperative imbalance of sagittal alignment have a higher risk of developing CASP after multi-level cervical surgery.

Experimental study of tendon sheath repair via decellularized amnion to prevent tendon adhesion.

The adhesion of tendon and surrounding tissue is the most common complication after repairing an injured tendon. The injured flexor tendons in zone II are frequently accompanied by tendon sheath defects, which lead to poor recovery. A variety of biological and non-biological materials have been recently used for repair or as substitute for tendon sheaths to prevent tendon adhesion. However, non-biological materials, such as polyethylene films, have been used to prevent tendon adhesions by mechanical isolation. The possibility of tendon necrosis and permanent foreign body remains due to the lack of permeability and the obstruction of nutrient infiltration. The natural macromolecule amniotic membrane derived from organisms is a semi-permeable membrane with the following characteristics: smooth; without vascular, nerve, and lymphatic; and rich in matrix, cytokines, enzymes, and other active ingredients. The unique structure of this membrane makes it an ideal biomaterial. In the experiment in Henry chicken, the model of tendon sheath defect and the flexor digitorum tendon in zone II was established and randomly divided into control group, medical membrane group, and decellularized amniotic membrane group. Samples were obtained at the 2nd, 4th, 8th, and 12th week after operation. General, histological, and biomechanical tests were performed to investigate the preventive effect of repaired tendon sheath by decallularized amniotic membrane. Experimental results showed the following: the amniotic membrane group and the medical membrane group had mild inflammatory reaction and tissue edema, and nearly no adhesion was observed in the surrounding tissue; the fibroblast-like cells were distributed in layers under the light microscope; the amniotic membrane group was denser than the medical membrane group cells, and numerous fibroblasts were disorganized in the control group. Biomechanical measurements showed that the sliding distance of tendon, the total flexion angle of the toes, and the tendon maximum tensile breaking strength at the early postoperative were significantly better than in the control group. Through this experiment, the amniotic membrane, as a natural biological substitute material in the construction of tendon sheath, can effectively inhibit exogenous healing and promote endogenous healing to prevent tendon adhesion.

Factors associated with union time of acute middle-third scaphoid fractures: an observational study.

BACKGROUND: The aim of this study was to investigate the union time of acute middle-third scaphoid fractures following treatments and to analyze the effect of different factors on late union. PATIENTS AND METHODS: We retrospectively reviewed patients with acute middle-third scaphoid fracture at our institution between January 2013 and December 2017. Patient demographics, fracture characteristics, and treatment strategy, such as age, gender, body mass index, habit of smoking, sides of injury, dominant hand, ulnar variance, multiple fractures, and treatment methods, were investigated. Univariate and multivariate analyses were used to identify possible predictive factors. RESULTS: A total of 132 patients with scaphoid fracture were included in our study. Operation was performed in 67 patients (50.8%), and conservative treatment was performed in the other 65 patients (49.2%). The union time was 7.2±0.5 weeks. In the multivariate logistic regression analysis, late diagnosis (odds ratio, 1.247; 95% CI, 1.022-1.521) and conservative treatment method (odds ratio, 1.615; 95% CI, 1.031-2.528) were identified as 2 independent predictors of late union in scaphoid fractures patients. Other parameters were not demonstrated to be predictive factors. CONCLUSION: Late diagnosis and conservative treatment were two factors associated with late union. Long time of follow-up is necessary for patient with these factors.

Predictive factors of symptomatic lumbar canal stenosis in patients after surgery for cervical spondylotic myelopathy.

BACKGROUND: The aim of this study was to determine the incidence of coexisting symptomatic lumbar canal stenosis (LCS) in patients after surgery for cervical spondylotic myelopathy (CSM) and identify possible predictive factors associated with it. MATERIALS AND METHODS: We retrospectively reviewed patients with CSM at our institution between January 2005 and December 2015. Clinical and radiographic factors including age, gender, body mass index, Japanese Orthopedic Association scores, cervical alignment, anteroposterior diameter of cervical canal, number of levels with CSM, and percentage of cervical cord compression were investigated. Symptomatic LCS was defined as leg symptoms and a narrowing of the lumbar spinal canal at one level at least, which is confirmed by magnetic resonance images of the lumbar spine. Univariate and multivariate analyses were used to identify possible predictive factors. Pearson correlation analysis was also conducted to analyze the association between cervical parameters and percentage of LCS. RESULTS: A total of 317 patients with CSM met the criteria for inclusion. There were 39 patients (12.3%) with LCS after cervical surgery during a mean of 7.3 years' follow-up. In the multivariate logistic regression analysis, narrow diameter of cervical canal (OR, 3.96; 95% CI, 1.20-13.04) was identified as the only independent predictor of symptomatic LCS in CSM patients. The correlation coefficient between anteroposterior diameter of cervical canal and severity of LCS indicated a significantly positive linear relationship with 0.536 (P<0.001). CONCLUSION: We found that narrow diameter of cervical canal was associated with symptomatic LCS in CSM patients. Patients with this risk factor should be informed the possibility of symptomatic LCS.

Prevalence of and risk factors for Modic change in patients with symptomatic cervical spondylosis: an observational study.

BACKGROUND: The aim of this study was to assess the prevalence of cervical Modic change (MC) in patients with cervical spondylosis and to develop a better understanding of the possible risk factors for the prevalence of MC. METHODS: Between January 2014 and April 2017, patients with cervical spondylosis were included in our study. All patients underwent magnetic resonance imaging (MRI) to evaluate the presence of MC. The MC was classified into three types according to the Modic classification. Potential risk factors were collected from demographic data, lifestyle variables, laboratory tests, and radiographic images. Both univariate and multivariate analysis were used to detect factors associated with MC. We further compared several variables related to fat metabolism between patients with Type 1 and Type 2 MC. RESULTS: The prevalence of MC in patients with cervical spondylosis was 9.24%. The MC was most frequent at C5-6, followed by C6-7, C4-5, and C3-4. The proportion of Type 1 MC in patients with neck pain was significantly higher than that in patients without neck pain (46.2% vs 13.6%, P=0.027). However, none of the variables associated with fat metabolism showed a significant difference between Type 1 and Type 2 MC. Multivariate logistic analysis showed that age ≥55 years (odds ratio [OR], 1.91; 95% confidence interval [CI], 1.22-2.98) and body mass index (BMI) ≥25 kg/m2 (OR, 2.41; 95% CI, 1.62-3.59) were two significant independent factors that are associated with cervical MC in patients with cervical spondylosis (P<0.05). CONCLUSION: It appears that advanced age and high BMI were two factors that may be responsible for cervical MC. Type 1 MC is associated with the prevalence of neck pain. However, we cannot confirm that Type 2 MC is correlated with fat metabolism.