Median Nerve Injury Research Articles

Median Nerve Injury in Ultrasound-Guided Hydrodissection and Corticosteroid Injections for Carpal Tunnel Syndrome

Purpose Permanent nerve damage after corticosteroid injection has been suggested when symptoms of median nerve injury (MNI) are irreversible. We assess the outcomes of MNI and their association with ultrasonography (US)-guided hydrodissection and the following corticosteroid injection for symptomatic carpal tunnel syndrome (CTS). Methods US-guided hydrodissection and the following corticosteroid injections were administered to 126 CTS patients. Occurrence of MNI, clinical data, and post-hydrodissection findings were evaluated. Post-hydrodissection findings included vascular injury during hydrodissection, altered echogenicity, reduced flattening ratio, and increased cross-sectional area of the MN at the inlet of the carpal tunnel (MN-CSA-Inlet) on ultrasonography after hydrodissection. The relevance of MNI with respect to these clinical data and findings was determined. The outcome was rated using Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) scores. Results Nine patients suffered MNI (incidence, 7.1 %) but improved significantly at follow-up. Clinical data and vascular injury during hydrodissection, altered echogenicity, and reduced flattening ratio after hydrodissection were unrelated to prolonged transient MNI (p > 0.05). MNI was significantly associated with increased CSA (p = 0.005). A CSA increase > 2 mm2 after hydrodissection yielded the greatest performance (0.979) for MNI in the receiver operating characteristic analysis. Decreases in BCTQ scores after injection did not differ significantly between groups with and without MNI (p > 0.05). Conclusion MNI during hydrodissection may be reversible. MNI is indicated by an increase in MN-CSA-inlet immediately after hydrodissection.

Incidence of major complication following embolo-sclerotherapy for upper and lower extremity vascular malformations.

The current literature on the major complications of embolo-sclerotherapy of upper and lower extremity vascular malformations is scarce. Evaluating and understanding the rates and types of potential major complications of embolo-sclerotherapy of vascular malformations help treatment planning and informed consent. Therefore, this study reviewed major complications following embolo-sclerotherapy of all upper and lower extremity vascular malformations in a single specialized multidisciplinary vascular malformation center over a 5-year period. All patients with vascular malformations underwent multidisciplinary directed intervention. Demographic, procedural, follow-up, and complication data were collected prospectively in a dedicated database, and reviewed retrospectively. Major complications for upper and lower extremity vascular malformations from 1 January 2013 to 31 December 2017 were analyzed. All embolo-sclerotherapies of high-flow vascular malformations (HFVMs) were performed under selective catheter angiography and direct injection, but low-flow vascular malformations (LFVM) with direct injection only. Major complications were defined as any tissue or functional damage caused by direct injection, distal embolization, or tissue reaction. Seventy patients (median age of 25 years; 44 males and 26 females) had 150 embolo-sclerotherapy procedures for upper extremity vascular malformation. Of these, 28 patients had embolo-sclerotherapy for HFVM and 42 patients for LFVM; total 78 and 72 procedures, respectively. A total of 107 patients (median age of 26 years; 42 males and 65 females) had 160 embolo-sclerotherapy interventions for lower extremity vascular malformations. Of these, 18 patients had embolo-sclerotherapy for HFVM and 89 patients for LFVM; total of 30 and 130 procedures, respectively. The overall major complication rates following embolo-sclerotherapy of upper and lower extremity vascular malformations were 14.3% and 4.7%, respectively (P = 0.030). In the upper extremity HFVM group, major complications from embolo-sclerotherapy occurred in five patients; three ischemic fingers requiring amputation and two skin ulcerations. Meanwhile, in the upper extremity LFVM group, major complications occurred in five patients; one median nerve injury requiring nerve grafting and hand therapy, one hand contracture requiring tendon release, and three skin ulcerations. There was only one major complication, which was cellulitis in the lower extremity HFVM group. In the lower extremity LFVM group, major complications occurred in four patients; two skin ulcerations, one cellulitis, and one deep vein thrombosis. Embolo-sclerotherapy is relatively safe for upper and lower extremity vascular malformations in a high-volume experienced center where our major complication rates were 14.3% and 4.7%, respectively, which compare favorably or similar to those reported in most recent literature. These outcomes will direct treatment strategies to avoid local and systemic toxic complications in the upper and lower extremity, for both HFVM and LFVM, and to improve informed consent.

Median Nerve Injury in Ultrasound-Guided Hydrodissection andCorticosteroid Injections for Carpal Tunnel Syndrome.

Permanent nerve damage after corticosteroid injection has been suggested when symptoms of median nerve injury (MNI) are irreversible. We assess the outcomes of MNI and their association with ultrasonography (US)-guided hydrodissection and the following corticosteroid injection for symptomatic carpal tunnel syndrome (CTS). US-guided hydrodissection and the following corticosteroid injections were administered to 126 CTS patients. Occurrence of MNI, clinical data, and post-hydrodissection findings were evaluated. Post-hydrodissection findings included vascular injury during hydrodissection, altered echogenicity, reduced flattening ratio, and increased cross-sectional area of the MN at the inlet of the carpal tunnel (MN-CSA-Inlet) on ultrasonography after hydrodissection. The relevance of MNI with respect to these clinical data and findings was determined. The outcome was rated using Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) scores. Nine patients suffered MNI (incidence, 7.1 %) but improved significantly at follow-up. Clinical data and vascular injury during hydrodissection, altered echogenicity, and reduced flattening ratio after hydrodissection were unrelated to prolonged transient MNI (p > 0.05). MNI was significantly associated with increased CSA (p = 0.005). A CSA increase > 2 mm2 after hydrodissection yielded the greatest performance (0.979) for MNI in the receiver operating characteristic analysis. Decreases in BCTQ scores after injection did not differ significantly between groups with and without MNI (p > 0.05). MNI during hydrodissection may be reversible. MNI is indicated by an increase in MN-CSA-inlet immediately after hydrodissection.

Functional evaluation of early tendon transfer for thumb opposition in median nerve palsy

BackgroundThere is paucity of literature on early tendon transfer in surgical rehabilitation of hands with median nerve injuries. Since the single most important functional deficit in median nerve palsy is the loss of thumb opposition, we evaluated the results of early tendon transfer in restoration of thumb opposition. MethodsThis prospective study involved 10 cases of isolated median nerve paralysis (axonotmesis or neurotmesis) that underwent early tendon transfer for restoration of thumb opposition. A pre- and post-operative evaluation in terms of power and precision grip strength and range of opposition of thumb was done. Median nerve exploration was performed in 4 cases and was supplemented by a tendon transfer for thumb opposition. The extensor indicis proprius (EIP) opponensplasty was performed in nine out of ten cases. In one case where the patient had scarring over the EIP tendon, palmaris longus (PL) opponensplasty was performed. ResultsThe median age at injury was 29 years (range; 8 years–57 years). Minimum period of follow-up was 6 months. Six patients who underwent EIP transfer had excellent opposition while 3 had good opposition. The patient, in whom PL opponensplasty was done, had an excellent opposition. The median time for return to work was 2.75 months.There was significant improvement in the power grip and all three types of precision grip at 6 months follow-up. The percentage deficit in the affected hand compared to the normal hand was significantly reduced. There was no case of tendon pull out in our study, nor did any of our patients have an extensor lag following EIP transfer. ConclusionEarly tendon transfer has a unique role in the management of median nerve palsy hand and we suggest this procedure should be considered in both high and low lesions.

Disinhibition of Human Primary Somatosensory Cortex After Median Nerve Transection and Reinnervation.

Despite state-of-the-art surgical and postoperative treatment, median nerve transection causes lasting impaired hand function due to limitations in the nerve’s reinnervation ability. The defective innervation and thus controllability of the affected hand can shape the brain’s control of manual behaviors. Earlier studies of changes in the processing of tactile stimuli have focused mainly on stimulation of the reinnervated hand and lack sufficient control over the brain’s use of the tactile input in perceptual terms. Here we used fMRI to measure brain activity (BOLD-signal) in 11 people with median nerve injury and healthy controls (N = 11) when performing demanding tactile tasks using the tip of either the index or little finger of either hand. For the nerve-injured group, the left median nerve had been traumatically transected in the distal forearm and surgically repaired on average 8 years before the study. The hand representation of their contralesional (right) primary somatosensory cortex (S1) showed greater activity compared to controls when the left reinnervated index finger was used, but also when the left-hand little finger and the fingers of the right hand innervated by uninjured nerves were used. We argue that the overall increase in activity reflects a general disinhibition of contralesional S1 consistent with an augmented functional reorganizational plasticity being an ongoing feature of chronic recovery from nerve injury. Also, the nerve-injured showed increased activity within three prefrontal cortical areas implicated in higher-level behavioral processing (dorsal anterior cingulate cortex, left ventrolateral prefrontal and right dorsolateral prefrontal cortex), suggesting that processes supporting decision-making and response-selection were computationally more demanding due to the compromised tactile sensibility.

Delayed Transfer of the Extensor Carpi Radialis Brevis Branch of the Radial Nerve to the Anterior Interosseous Nerve for Restoration of Thumb and Index Finger Flexion: Case Report.

High median nerve injuries (HMNIs) are rare lesions involving the upper extremities and affect the median nerve from its origin to the emergence of the anterior interosseous nerve (AIN). Proximal reconstruction has long been considered the gold standard in treating HMNI, but thumb and index flexion and pinch and grip weakness are consistently not recovered. We report the surgical results of a patient affected by an HMNI with partial spontaneous recovery after a gunshot wound. AIN function was successfully restored in a delayed fashion by transferring the radial nerve branch to the extensor carpi radialis brevis to the AIN.

Acute and long-term costs of 268 peripheral nerve injuries in the upper extremity.

BackgroundPeripheral nerve injury in the upper extremity is linked to high socioeconomic burden, yet cost-analyses are rare and from small cohorts. The objective of this study was to determine the costs and long-term socioeconomic effects of peripheral nerve injuries in the upper extremity in Germany.MethodsWe analyzed data of 250 patients with 268 work-related upper extremity nerve injuries from acute treatment to long-term follow-up on rehabilitation, sick-leave and disability-pension.ResultsPatients were on average 39.9±14.2 years old, male (85%) and mean inpatient treatment was 7±6 days. Location of nerve was 8% (N = 19) proximal to the wrist, 26% (N = 65) at the wrist and metacarpus, and 66% (N = 166) at phalangeal level. Acute in-patient treatment for (single) median nerve injury accounted for 66% with hospital reimbursement of 3.570€, ulnar nerve injury for 24% and 2.650€ and radial nerve injury for 10% and 3.166€, all including finger nerve injuries. The remaining were combined nerve injuries, with significantly higher costs, especially if combined with tendon 5.086€ or vascular injury 4.886€. Based on location, nerve injuries proximal to the wrist averaged 5.360±6.429€, at the wrist and metacarpus 3.534±2.710€ and at the phalangeal level 3.418±3.330€. 16% required rehabilitation with average costs of 5.842€ and stay of 41±21 days. Sick leave was between 11–1109 days with an average of 147 days with socioeconomic costs of 197€/day, equaling on average 17.640€. 30% received a mean yearly disability pension of 3.187€, that would account to 102.167€ per lifetime.ConclusionThis large German patient sample indicates that nerve injury has a major impact on function and employment, resulting in significant health care costs. Both proximal and distal nerve injuries led to long-term disability, subsequent sick-leave and in 30% to permanent disability pension. These data are determined to support future studies and health economical work on prevention, treatment and rehabilitation of these often small injuries with great consequences.

A novel nerve transfer: The first palmar interosseous motor branch of the ulnar nerve to the recurrent motor branch of the median nerve

IntroductionThe recovery of recurrent motor branch of the median nerve might be delayed in high level median nerve injuries due to the long reinnervation distance. The aim of this study is to define a novel nerve transfer to restore the opposition and pinch. MethodsTwo fresh frozen hand cadavers were used for the study. The motor branch of the first palmar interosseous muscle of the ulnar nerve was identified and dissected. Thenar branch of the median nerve was dissected from its insertion site. The motor branch of the first palmar interosseous muscle of the ulnar nerve was transferred to the thenar motor branch of the median nerve. Axon counts were examined histopathologically. Clinically this nerve transfer was performed for two female patients with a high-level median nerve injury. Mehta opposition scores were 21 and 20, respectively and the results were satisfactory six months after the surgery. DiscussionAlthough exploration and repair are recommended as the first treatment for median nerve injuries, the waiting time until the motor branch is reinnervated is critical in high level lesions. Nerve transfers become very important for fast recovery. ConclusionsThis new nerve transfer proposal may be an important step in nerve transfer surgery.

Complications After Distal Biceps Tendon Repair: A Systematic Review

Background: Distal biceps tendon injuries typically occur in the dominant arm of men in their fourth decade of life. Surgical repair restores flexion and supination strength, resulting in good functional outcome. The complication profile of each surgical approach and fixation technique has not been widely studied in the literature. Purpose: To report the rate of complications after repair of complete distal biceps ruptures, to classify them according to surgical approach and fixation technique, and to analyze risk factors and outcomes of the individual complications. Study Design: Systematic review. Methods: Studies published in English on primary repair of the distal biceps between January 1998 and January 2019 were identified. Data on complications were extracted and classified as major and minor for analysis. A quantitative synthesis of data was done to compare the complication rates between (1) limited anterior incision, extensile anterior incision, and double incision and (2) 4 fixation methods. Results: Seventy-two articles including 3091 primary distal biceps repairs were identified. The overall complication rate was 25% (n = 774). The major complication rate was 4.6% (n = 144) and included a 1.6% (n = 51) rate of posterior interosseous nerve injury; 0.3% (n = 10), median nerve injury; 1.4% (n = 43), rerupture; and a 0.1% (n = 4), synostosis. Brachial artery injury, ulnar nerve injury, compartment syndrome, proximal radius fracture, and chronic regional pain syndrome occurred at a rate of <0.1% each. The majority of nerve injuries resolved with an expectant approach. The minor complication rate was 20.4% (n = 630). The most common complication was lateral cutaneous nerve injury (9.2%, n = 283). An extensile single incision was associated with a higher rate of superficial radial nerve injury when compared to limited single incision(6% vs 2.1%, P = .002). Limited anterior single incision technique had a higher rate of lateral antebrachial cutaneous nerve injury compared to extensile single incision. (9.7% vs 5.2%, P = .03). Synostosis occurred only with double incision. Fixation technique had no significant effect on rerupture rate and posterior interosseous nerve injury rate. Conclusion: This is the largest analysis of complications after distal biceps repair, indicating a major complication rate of 4.6%. This study provides valuable data with regard to the choice of technique, surgical approach, and rate of complications, which is essential for surgical planning and patient consent. Registration: CRD42017074066 (PROSPERO).

Outcomes and Return to Work Following Complex Nerve Lacerations in the Volar Forearm in an Underserved Spanish-Speaking Population

PurposeLacerations to the ulnar and median nerve in the volar forearm have demonstrated considerable long-term clinical and socioeconomic impacts on patients. The purpose of this study was to evaluate the outcomes of complex volar forearm lacerations involving one or more major peripheral nerves in an economically disadvantaged patient population.MethodsIn this study, a retrospective analysis of 61 patients who sustained lacerations to the median nerve, ulnar nerve, or both with volar wrist lacerations was performed. Each patient’s preinjury and postinjury occupation, dominant extremity, and demographic variables were evaluated. Sensation recovery, motor recovery, Disabilities of the Arm, Shoulder, and Hand scores, visual analog scale scores, cold intolerance, and return to work were evaluated at 3, 6, and 12 months after the injury.ResultsPatients with isolated median nerve injuries demonstrated improved motor recovery compared with patients with isolated ulnar nerve injuries. Patients with combined nerve injuries had worse sensation recovery and motor recovery, and lower rates of return to work than either group of patients with isolated nerve injuries. Manual laborers had worse motor recovery and lower rates of return to work than did patients who were office workers.ConclusionsPatients with combined median and ulnar nerve injuries have worse functional recovery and lower rates of return to work than do patients with isolated median or isolated ulnar nerve injuries at 1 year. Manual laborers demonstrated worse functional recovery and lower rates of return to work compared with office workers at 1 year.Type of study/level of evidenceTherapeutic III.

Open Reduction of Neglected Supracondylar Humeral Fractures With Callus Formation in Children.

The standard treatment for supracondylar humeral fractures (SHFs) in children is closed reduction and percutaneous Kirschner (K)-wire fixation. In patients who present >14 days after injury and show callus formation, this procedure cannot be performed. There are 2 options in these cases: functional exercises with osteotomy performed at a later stage if cubitus varus is present, or immediate open reduction and percutaneous K-wire fixation. This study aimed to evaluate the outcomes of K-wire fixation through an anterior approach in children with neglected SHF and identify factors predicting the outcomes. This retrospective study assessed the files of 32 children treated for neglected SHF at our hospital between June 2015 and May 2018. An incision was made along the anterior transverse groove of the elbow. The callus was removed, the fracture was reduced, and K-wire fixation was performed. The outcome evaluation included the radiological Baumann angle, pin fixation construct, carrying angles, and the functional outcome was Mayo Elbow Performance Score and Flynn criteria. Binary regression analysis compared the functional outcome as the dependent variable with age, time from injury to operation, operation time, and the amount of callus. The interval between injury and operation was 14 to 40 days (average, 22.4 d). Patients were followed for 12 to 36 months (average, 21.5 mo). Fracture healing took 5 to 8 weeks (average, 6.6 wk). No patient had a vascular injury or compartment syndrome. Twelve patients were intraoperatively assessed for radial and median nerve injury. No nerve repair was required. All nerve injuries recovered within 3 months. No iatrogenic ulnar nerve injury occurred. One patient had an infected incision. Binary regression analysis showed that the time elapsed between injury and operation (P=0.033) and Gartland type (P=0.008) were inversely correlated with outcomes; the longer the duration, the poorer the outcomes. The functional outcomes after open reduction and K-wire fixation through an anterior approach were poorer with longer time to surgery and Gartland type. Level III.

Syndrome du canal carpien : des causes rares et des formes associées derrière une affection commune et stéréotypée

Carpal tunnel syndrome (CTS) is too common a condition not to daily interact with the practitioner, if only because of its entanglement to other pathologies, causal or chance association. The typical symptomatology, with hand paresthesia and morning pain upon waking, is related to a median nerve injury in the confined space of the carpal tunnel, more often by local inflammation and tenosynovitis of the finger flexors (repetitive activity of the hands). SCC may be secondary to situations (pregnancy) or conditions (edema, hypothyroidism…), which exaggerate the ordinary pathophysiology or cause deposits in the channel (amyloidosis, mucopolysaccharidoses, etc.). Otherwise, SCC is favored by all neuropathies that cause nerve fragility (especially diabetes). It is sometimes the first sign of these various affections of which it can allow early diagnosis. Electroneuromyographic examination (ENMG) is a key examination to confirm the diagnosis (slowing of sensitive and motor conduction of the median nerve through the carpal tunnel, due to local demyelination), to look for a predisposing neuropathy and for signs of seriousness (amplitude reduction of electrophysiological signals) that indicate axonal loss. In SCC forms with only slowed conduction without sign of seriousness, a splint or infiltration treatment may be attempted. If this medical treatment does not bring healing, or if there are signs of seriousness or unbearable pains, a decompression surgery is indicated. Whether it is performed traditionally or endoscopically, it provides fast relief, even immediate.

Study of patient and injury related prognostic predictors of motor and sensory recovery in Ulnar nerve injuries - A three-year experience at tertiary care hospital in Himalayan region.

Background: Ulnar nerve integrity is a prerequisite for normal hand function. The ulnar nerve is a frequently injured nerve, and recent evidence indicates that nerve surgery may produce acceptable outcomes.The outcome of the ulnar nerve repair depends upon different factors.The present study provides the surgical outcome of ulnar nerve injuries and studies the patient and injury related factors as prognostic predictors of motor and sensory recovey. Materials and Methods: In this prospective study, patients with ulnar nerve injuries due to trauma, undergoing primary surgical repair by a single microsurgeon over a period of 3 years (Aug 2014 – Jul 2017) were selected.The demographic data, injury characteristics were studied and their impact on the surgical outcome assessed at 2- year follow-up. Results: A total of 62 patients (48 males and 14 females with a male: female ratio of 3.42:1) fulfilled the inclusion criteria. Majority of them [39/62 (62.90%)] were in the age group of 16 to 40 years. Glass cut and knife cut were the most common modes of injury in males 24/62(50%) and females 9/14(64.28%) respectively. At 2-year follow up, 80% children had good and motor recoveries while only in 30 % patients above 60 years of age fair recovery was reported.. In 85% of injuries at the wrist level, the outcome was good while in 70% of proximal forearm injuries, it was Fair. Sensory and motor recovery was good only in 32% of sharp injuries while as in the rest it was fair. In 70% of the subjects with associated injuries involving median nerve, both radial and ulnar arteries and all flexor tendons, recovery was fair while 30% of such cases had Poor results. Conclusions: We concluded that clean cut distal ulnar nerve injuries have good outcome in younger patients.Isolated ulnar nerve injury has good outcome but when associated with median nerve injury, tendon injury or double vessel injury, the outcome is Poor.

A Novel Supraretinacular Endoscopic Carpal Tunnel Release: Instrumentation and Technique (Cadaveric Study)

Purpose Endoscopic carpal tunnel release has been shown to be associated with a shorter return to work compared with open carpal tunnel release in the treatment of carpal tunnel syndrome. Unfortunately, it may be associated with a higher risk for median nerve injury when the carpal tunnel is used as a portal for instrumentation. The purpose of this study was to assess safety in using a newly designed retractor through a supraretinacular approach. Methods We used 8 wrists (4 left and 4 right wrists) from 4 fresh-frozen cadavers for this study. Supraretinacular endoscopic carpal tunnel release using the supraretinacular retractor was performed by a single investigator, followed by exploration of the carpal tunnel and the structures surrounding it. Surgeries were performed using a new surgical instrument consisting of an arch-shaped blade and handle. It includes a retainer adapted to receive a 2.4- or 2.7-mm endoscope and to retain it at the apex of the arch, which can be moved in and out to visualize the entire transverse carpal ligament. The space below the blade is also used as a portal to insert scissors and instrumentation to cut the transverse carpal ligament. Results All 8 carpal tunnels were completely released with no injury to the median nerve, superficial palmar arch, flexor tendon, or violation into Guyon canal. Mean distance of the flexor retinaculum division to the recurrent motor branch, palmar cutaneous branch, and superficial palmar arch was 6.87 ± 2.80, 7.13 ± 5.33, and 9.13 ± 4.42 mm, respectively. All specimens had an extraligamentous recurrent motor branch. Conclusions The retractor and described technique were safe and effective in this cadaveric study. Further clinical trials are necessary before it can be adopted as a safe and reliable technique. Type of study/level of evidence Therapeutic IV.

Quantitative assessment of cortical somatosensory digit representations after median and ulnar nerve injury in rats.

Incomplete recovery of sensory function is common after peripheral nerve injury (PNI). Despite reinnervation following injury, disorganized cortical representations persist and may contribute to functional deficits. There is a dearth of literature characterizing cortical responses after PNI in rodent models. Here we develop a quantitative electrophysiological method for mapping forepaw digit responses in primary somatosensory cortex (S1) of rats. We tested the hypothesis that PNI in the forelimb would generate significant, long lasting sensory deficits, and corresponding disorganization in S1. Rats underwent a transection of the proximal segment of the median and ulnar nerves in the forelimb followed by tubular repair. 4-12 months after nerve injury, we tested mechanosensory withdrawal thresholds and mapped S1 responses to mechanical stimulation of the digits. PNI produces persistent elevation of mechanical withdrawal thresholds, consistent with an impairment in sensory function. Assessment of cortical neurophysiology reveals a substantial disorganization of S1 somatotopy. Additionally, we document degraded timing and digit specificity of cortical responses. This quantitative measurement of long-term changes in S1 digit representations after forelimb nerve injury in rodents provides a framework for further studies focused on the development of therapeutic strategies to restore cortical and sensory function.

The Median Nerve Injury Model in Pre-clinical Research - A Critical Review on Benefits and Limitations.

The successful introduction of innovative treatment strategies into clinical practise strongly depends on the availability of effective experimental models and their reliable pre-clinical assessment. Considering pre-clinical research for peripheral nerve repair and reconstruction, the far most used nerve regeneration model in the last decades is the sciatic nerve injury and repair model. More recently, the use of the median nerve injury and repair model has gained increasing attention due to some significant advantages it provides compared to sciatic nerve injury. Outstanding advantages are the availability of reliable behavioural tests for assessing posttraumatic voluntary motor recovery and a much lower impact on the animal wellbeing. In this article, the potential application of the median nerve injury and repair model in pre-clinical research is reviewed. In addition, we provide a synthetic overview of a variety of methods that can be applied in this model for nerve regeneration assessment. This article is aimed at helping researchers in adequately adopting this in vivo model for pre-clinical evaluation of peripheral nerve reconstruction as well as for interpreting the results in a translational perspective.

New basic insights on the potential of a chitosan-based medical device for improving functional recovery after radical prostatectomy.

To evaluate: (i) the neuro-regenerative potential of chitosan membrane (CS-Me) on acutely axotomised autonomic neurones in vitro; (ii) to exclude the possibility that a pro-regenerative biomaterial could interfere with the proliferation activity of prostate cancer cell lines; (iii) to provide an in vivo proof of the biocompatibility and regeneration promoting effect of CS-Me in a standardised rat model of peripheral nerve injury and repair; (iv) finally, to evaluate the tissue reaction induced by the degrading material; as previous studies have shown promising effects of CS-Me for protection of the neurovascular bundles for potency recovery in patients that undergo nerve-sparing radical prostatectomy (RP). Addressing aim (i), the neuro-regenerative potential, organotypic cultures derived from primary sympathetic ganglia were cultured on CS-Me over 3days and neurite extension and axonal sprouting were evaluated. Addressing aim (ii), effects of CS on cancer cells, different human prostate cancer cell lines (PC3, DU-145, LN-Cap) were seeded on CS-coated plates or cultured in the presence of CS-Me dissolution products. Addressing aims (iii) and (iv), functional recovery of peripheral nerve fibres and tissue reaction with the biomaterial, CS-Me and CS nerve guides were used to repair a median nerve injury in the rat. Functional recovery was evaluated during the post-recovery time by the behavioural grasping test. CS-Me significantly stimulated axon elongation from autonomic ganglia in comparison to control conditions in organotypic three-dimensional cultures. CS coating, as well as the dissolution products of CS-Me, led to a significantly lower proliferation rate of prostate cancer cell lines in vitro. Tissue reaction towards CS-Me and standard CS nerve guides was similar in the rat median nerve model, as was the outcome of nerve fibre regeneration and functional recovery. The results of this study provide the first experimental evidence in support of the clinical safety of CS-Me and of their postulated effectiveness for improving functional recovery after RP. The presented results are coherent in demonstrating that acutely axotomised autonomic neurones show increased neurite outgrowth on CS-Me substrate, whilst the same substrate reduces prostate cancer cell line proliferation in vitro. Furthermore, CS-Me do not demonstrate any disadvantage for peripheral nerve repair in a standard animal model.

Brachial pseudoaneurysm associated with median nerve injury as a complication of peripherally inserted central catheter: A case report

Introduction: Peripherally inserted central venous catheters (PICCs) have been increasingly used as an alternative to conventional central venous catheters for long-term administration of chemotherapy,..

Prediction Model for Choosing Needle Length to Minimize Risk of Median Nerve Puncture With Dry Needling of the Pronator Teres

ObjectiveThe aim of this study was to relate forearm anthropometric measures to ultrasound pronator teres depth to determine the necessary needle length to prevent median nerve (MN) injury during pronator teres dry needling. MethodsWe conducted a study employing a diagnostic accuracy prediction model (NCT03308279) at a Spanish university center. The study recruited 65 participants to predict the depth of the MN (measured with ultrasound) in the pronator teres using a decision tree algorithm to reduce the risk of MN puncture using 2 needle lengths (13 mm or 25 mm). The decision tree was developed by automatically selecting a cutoff for body mass index, forearm length and circumference, and pronator teres thickness. ResultsFor forearm circumferences ≤27.5 cm, the predictive value for the 13-mm needle was 92%. For forearm circumferences >27.5 cm and forearm lengths ≤26.75 cm, the predictive value for the 25-mm needle was 100%. ConclusionBased upon the findings of this study, we suggest that needle length should be selected according to forearm anthropometric measures to prevent MN injury during pronator teres dry needling.

P30-F Ultrasound evaluation of presumed carpal tunnel syndrome after distal radius fracture

Background CTS (carpal tunnel syndrome) has been reported as one of the major complications following DRF (distal radius fracture). The diagnosis is usually based on clinical examination and EDX (electrodiagnostic studies). We examined the role of HRU (high resonance ultrasonography) in differentiating CTS from other involvement of the median nerve in patients with DRF. Material and methods 17 patients with prior DRF and clinical presentation and EDX findings consistent with CTS were examined by HRU. 2 of these patients were diagnosed and surgically treated for CTS prior to the HRU examination, with no benefit. Results The EDXs were consistent with CTS of different severity grade in all 17 patients. HRU examination of the median nerve revealed compression of the median nerve at the level of the carpal tunnel in 2 cases. In the other 15 patients no sign of compression was found under the transverse ligament, but permitted to visualise focal or segmental thickening, alteration of the fascicular structure of the median nerve (all 15 cases), neuroma (6 cases) and increased vascularization (3 cases) on the side of the fracture. Conclusion HRU is a non-invasive and reliable method, that allows diagnostic accuracy in the assessment of median nerve injury following DRF. HRU showed a specificity superior to common EDX on determining the nature of the median nerve involvement in our patients and helped differentiating from the presumed CTS.