Digital Nerve Research Articles

Result of Percutaneous Release of Trigger Thumb: A Prospective Study

Introduction: Trigger thumb is a common disorder characterized by pain, snapping, and locking of fingers. It usually affects the ring and thumb finger. The treatment of trigger thumb varies according to the grade of triggering. Open surgical release of A1 pulley in trigger thumb is a widely accepted treatment method having its complications like scar mark, pain at the incision site, joint stiffness, and digital nerve injuries. The percutaneous release does have good results in recent studies. It is an easy daycare procedure with low complications. Methods: This study includes 28 patients with trigger thumbs who underwent percutaneous release. Patients were followed up for 6 months duration. Results: There were 30 patients included in the study, only 2 patients required open release so we had an overall 93.33% success rate of percutaneous release. There was no clinical evidence of complications and nerve injury. Conclusion: The percutaneous release is a safe and effective outpatient procedure in patients with trigger thumbs.

Cryoneurolysis for Digital Neuralgia in Professional Baseball Players: A Case Series

We describe a non-surgical approach to refractory digital neuralgia using cryoneurolysis in a series of 3 professional baseball players. Thumb injuries are common in baseball players and can sometimes be challenging to effectively manage. Depending on the injury, current treatments include anti-inflammatories, immobilization, physical therapy, corticosteroid injections, and/or surgery. A subset of patients, however, fail nonoperative management yet do not have a clear indication for surgery. Cryoneurolysis or cyroanalgesia is an FDA-approved form of neuromodulation, which has been used safely and effectively on a variety of peripheral nerves. The mechanism of action involves percutaneous introduction of a small probe under local anesthetic to nerve tissue using ultrasound guidance. The probe is then cooled to -88°C using nitrous oxide, which results in secondary Wallerian degeneration. Axonal and myelin regeneration occurs completely in 3-6 months. Visualization of the superficial radial sensory and ulnar digital nerve were obtained under ultrasound. The skin was prepared in sterile fashion. A 22-gauge 1-½ inch needle was then advanced with ultrasound guidance, and local anesthetic was applied. Both treatment sites were marked with skin marker. Cryoneurolysis was employed using a 5 mm tip. 60-second treatment cycles were performed at each site. Each of the cycles resulted in a 5 × 7 mm lesion visible as hypoechoic signal. All 3 players endorsed significant and prolonged relief and were able to return to an elite level of play. This manuscript is subject to all of the limitations of a case series, and larger rigorous studies are needed to illuminate causal inferences. Novel, complex technologies may also be more susceptible to placebo effect. Nonetheless, we are able to report marked efficacy and safety from cryoneurolysis of the ulnar digital nerve and the superficial radial sensory nerve in a small group of elite baseball players with refractory digital neuralgia.

Versatility of Vein Grafts in Hand Neurovascular Reconstruction – Clinical Cases and Literature Review

Injuries to the upper limb may determine unexpected simple or complex soft tissue defects, due to different types of underlying injury mechanism, clean cut/stabs, crushing, torsion, avulsion or mixed types, which pose a challenge for the reconstructive surgeon. Ideally, all arterial, venous and nervous lesions, in the distal upper limb should be repaired in an end-to-end technique, outside of injury zones, with healthy ends, in a tension free manner. However, situations arise where, either a tension-free repair is not possible, or a considerable defect is met, often representing a challenge to the surgeon. Therefore, a timely decision is imposed in order to find the most favorable approach to restore limb or segment perfusion, ensuring efficient venous return, as well as providing a sensate repair. Usage of vein grafts represents an essential tool comprised in the reconstructive surgeon’s armamentarium, with high versatility in nerve, arterial and venous reconstruction. Not only does it provide an ideal solution, with high adaptability to each case, but it also may enhance short- and long-term outcome, offering an optimal reconstructive option in any upper limb trauma situation, regardless of etiology. We aim to describe our therapeutic strategies in a series of challenging trauma cases involving digital structures from the upper limb. Interposed vein grafts were used to re-stablish sensate function in a patient with a collateral digital nerve defect, but also to bridge vital digit arterial defect in a torsion-avulsion thumb amputation, as well as re-establishing venous flow in patients with Urbaniak II finger degloving injury.

Schwannoma of the digital nerve

Schwannomas are the most common benign tumours affecting the peripheral nervous system. They represent a benign proliferation of Schwann cells. Schwannomas and other peripheral nerve sheath tumours are common in the head and neck, spine, thorax, abdominal wall, and retroperitoneum. However, localization in hand is exceptional. We present a 22-years-old female patient diagnosed and operated on for schwannoma of the digital nerve (dorsal cutaneous branch originating from the palmar cutaneous branch of ulnar nerve). In the case of a palpable hand mass, one of the possible diagnoses is schwannoma, and since the operative technique is somewhat specific with tumour enucleation and internal neurolysis, it is necessary to preoperatively keep in mind schwannoma in the differential diagnosis.

Segmental schwannomatosis in the upper extremity: a case report and review of the literature

Schwannomas, the most frequently occurring benign tumors of the peripheral nerve sheath, generally remain as painless swellings for several years before diagnosis. Multiple schwannomas involving different nerves within the same extremity are rare. We report a rare case of a 61-year-old female patient who presented with multiple schwannomas in the palmar common and proper digital nerves, 15 years after the resection of a median nerve schwannoma within the same upper extremity. Using pre-established diagnostic criteria, she was diagnosed with segmental schwannomatosis. After careful surgical resection, biopsy confirmed the diagnosis, and she recovered without neurological symptoms or limitations in the range of motion. A literature review revealed only four case series on segmental schwannomatosis, indicating its rarity. Postoperative sensory deficits are more likely in cases with multiple schwannomas in the common and proper digital nerves. We demonstrate that such complications can be avoided by meticulous dissection and separation of the tumors from the nerve fibers.

Failed Acellular Nerve Allografts: A Critical Review.

Acellular nerve allograft (ANA) occupies an increasingly prominent role in the treatment of peripheral nerve reconstruction. There is demonstrable efficacy; however, some grafts fail to support axonal regrowth and the reasons for this are unclear. This study examines the ANA experience in a specialized peripheral nerve surgery department to discuss the clinical and histological findings in failed cases. Failed ANA grafts were identified from a prospective database using Medical Research Council Classification (MRCC) S3 and M3 as thresholds for success. Cases in which ANA grafting was indicated for nerve related pain and dysesthesia but where no subjective improvement in symptoms occurred were also included. Patients requiring revision surgery after ANA grafting were also considered failures. Cases were then examined in conjunction with a literature review to identify possible mechanisms of failure, including detailed histological analysis in 2 cases. Eight failed procedures were identified from a database of 99 separate allograft records on 74 patients. This included procedures for 2 tibial nerves, 2 superficial radial nerves, 2 median nerves, 1 digital nerve and a lateral cord brachial plexus injury (male/female, 5:3; age range, 24-54 years). Allograft length range 25 to 120 mm. One postoperative infection was identified. Histological findings in 2 cases included adequate vascularization of allograft material without subsequent axonal regeneration, a reduction of large myelinated fibers proximal to a tibial nerve allograft in the setting of a chronic injury, and a preference for small rather than large fiber regeneration. This article reports instances of ANA graft failure in a variety of contexts, for which the primary reasons for failure remain unclear. The etiology is likely to be multifactorial with both patient, graft and surgeon factors contributing to failure. Further clinical and histological analysis of ANA failures will improve our understanding of the mechanisms of graft failure.

"The Feasibility of Targeted Muscle Reinnervation for the Management of Morton's Neuroma".

Despite multiple surgical modalities available for the management of Morton's neuroma, complications remain common. Targeted muscle reinnervation (TMR) has yet to be explored as an option for the prevention of recurrence of Morton's neuroma. The purpose of the present investigation was to determine the consistency of the relevant foot neurovascular and muscle anatomy and to demonstrate the feasibility of TMR as an option for Morton's neuroma. The anatomy of 5 fresh-tissue donor cadaver feet was studied, including the course and location of the medial and lateral plantar nerves (MPNs and LPNs), motor branches to abductor hallucis (AH) and flexor digitorum brevis (FDB), as well as the course of sensory plantar digital nerves. Measurements for the locations of the muscular and sensory branches were taken relative to landmarks including the navicular tuberosity (NT), AH, FDB, and the third metatarsophalangeal joint (third MTPJ). The mean number of nerve branches to FDB identified was 2. These branch points occurred at an average of 8.6 cm down the MPN or LPN, 9.0 cm from the third MTPJ, 3.0 cm distal to AH distal edge, and 4.8 cm from the NT. The mean number of nerves to AH was 2.2. These branch points occurred at an average of 6.3 cm down the MPN, 11.9 cm from the third MTPJ, 0.8 cm from the AH distal edge, and 3.8 cm from the NT. Recurrent interdigital neuroma, painful scar, and neuropathic pain are common complications of operative management for Morton's neuroma. Targeted muscle reinnervation is a technique that has demonstrated efficacy for the prevention and treatment of neuroma, neuropathic pain, and phantom limb pain in amputees. Herein, we have described the neuromuscular anatomy for the application of TMR for the management of Morton's neuroma. Target muscles, including the AH and FDB, have consistent innervation patterns in the foot, and consequently, TMR represents a viable option to consider for the management of recalcitrant Morton's neuroma. V.

Complex table saw hand injury-case report

Abstract Currently, Romania lacks a tradition of trade schools. This is due to the lack of awareness on the importance of this educational structure. Such multiple trades have been learned by simple observation from one individual to another. The importance of security measures has been taken for granted if not ignored. The number of traumas produced in wood processing has decreased rapidly due to the appearance of wood processing robots, the human factor being reduced only to their programming. The cases that arrive in the emergency departments are in a major percentage from the rural area, where the wood processing is done in the household without an adequate training and without going through a learning process. Hand injuries represent a great part of the Emergency Department presentations, and because of their fundamental functional use in daily life, repair of such lesions should be done with utmost care. Wounds of the hand typically have different degrees of severity depending on the mechanism of injury. Hand trauma probably represents the most frequent pathology of a plastic surgery ER and it should be handled with utmost care because of the fundamental function in the daily routine. The present article presents the therapeutic conduct of a complex case, multiple wounds with bone exposure, digital nerve sectioning and destruction of the flexor system of several fingers.

The effect of digital nerve block on the accuracy of hemoglobin monitoring during surgery: A randomized clinical trial

Background: The decision to transfuse blood products to patients during surgery is critical, due to the potential complications and costs of transfusion. Measuring hemoglobin level by spectrophotometry (SpHb) plays an important role in making this decision. The accuracy of SpHb depends on the finger perfusion. Since digital nerve blocks (DNB) can enhance blood circulation, we aimed at investigating DNB effects on the accuracy of SpHb. Methods: Patients undergoing spine surgery were randomly assigned to two groups. Group A received DNB in the left hand, and group B received DNB in the right hand. In each group, the other hand was considered as the control. Rainbow adult ReSposable sensors were attached to the patients’ both hands. Before surgical incision and every 1.5 hours, the SpHb values of both hands and the perfusion index were recorded. Concomitantly, arterial blood samples were drawn and sent to the lab for hemoglobin concentration measurement. This served as the gold standard for assessing hemoglobin levels (labHb). We used a mixed-effects generalized linear model to test the effect of independent variables on the difference between SpHb and labHb at each time point. Results: The SpHb displayed higher hemoglobin levels than those assessed by the lab. For lower labHb values, the SpHb-labHb differences were larger. A one-unit decrease in labHb increased the difference between SpHb and labHb by 0.56 g dL -1 , which was statistically significant. DNB significantly increased the difference between SpHb and labHb by 0.42 g dL -1 . The effect of DNB on the difference between SpHb and labHb was significant up to three hours after the beginning of surgery (0.58 g dL -1 difference between blocked and non-blocked hands). Conclusion: This study shows that, when hemoglobin levels are low, the accuracy of spectrophotometry decreases. Although DNB increases finger perfusion, it leads to an overestimation of hemoglobin levels by SpHb.

Evaluation of vapocoolant spray effect on pain reduction during digital nerve block: A randomized clinical trial.

The digital nerve block is an effective method of anesthesia before minor surgical interventions on the fingers. However, patients may experience a lot of pain and anxiety during this procedure. The efficacy of topical vapocoolant spray during minor procedures has been demonstrated in previous studies. we aimed to evaluate the effectiveness of topical vapocoolant spray in reducing pain during digital nerve block. This prospective, randomized clinical study was conducted to evaluate the effectiveness of vapocoolant spray application in reducing pain during digital block. The patients were categorized into 2 groups as spray-treated and control group. A routine digital block process was applied to the control group. Spray application was performed in two groups of 50 each, in a manner of bilateral and unilateral to the finger. Demographic data of the patients, such as gender, age, dominant hand, injury patterns, injection site and injury sites, were recorded. After the application, the patients' visual analog scale (VAS) was evaluated. Of the participants, 100 were randomly assigned to the vapocoolant spray-treated group, and 50 were included in the control group. The VAS pain score during penetration in both spray groups was significantly lower than the control group (p < 0.001). Pain change during penetration was found to be significantly lower in the bilateral spray-treated group compared to the control group (p < 0.001). Pain change during infiltration was significantly lower in both spray groups compared to the control group (p < 0.001). Spray application prior to digital nerve blocking can be used to reduce needle penetration pain associated with this procedure and pain associated with local anesthetic infiltration.

Superficial Communication Between Ulnar and Media Nerves in the Hand. An Anatomical Study

The objective of this study was to characterize the communication between ulnar and the median nerve in the superficial palmar region from a sample of mestizo-raced population predominant in Latin America. The superficial palmar regions of 53 fresh cadaveric specimens were evaluated, whom of which underwent necropsy procedure at the Institute of Legal Medicine. Dissection was performed by planes until visualizing the presence of the Communicating Branch (CB) between the digital branches of the ulnar nerve (UN) and the median nerve (MN). Qualitative and morphometric evaluation of the CB was carried out. A CB were observed in 82/ 106 (77.4 %) of the cadaveric specimens studied, of which, 38/53 (71.7 %) were bilateral, 15/53 (28.3 %) unilateral; this being a statistically significant difference (p <0.002). Oblique trajectory of the CB between the fourth and third common digital nerve was observed in 70 (85.4 %) specimens, while the CB with transverse trajectory was found in 7 (8.5 %) regions and in a plexiform form in 5 (6.1 %) cases. The length of the CB was 20.2 ± 5.1 mm and the distances from the upper edge of the flexor retinaculum to the proximal and distal points of the CB were 25 ± 6 mm and 37.4 ± 8.3 mm respectively. The anatomical characteristics of the CB patterns, as well as the morphometric CB findings and their points of reference from the carpal flexor retinaculum, make it possible to delimit a safe area of surgical access in the first-fifth proximal of the palmar region, during the surgical approach of carpal tunnel syndrome.

Ultrasonographic evaluation of the median nerve: normal and variant anatomy and appearance.

The median nerve is a mixed sensory and motor nerve that innervates part of the flexor muscles in the anterior compartment of the forearm and muscles in the lateral part of the hand; palmar cutaneous and digital cutaneous nerves branch from the median nerve, which provides sensory innervation to the skin on the radial side of the palm. Also, the median nerve is an object of interest because neuropathy of the median nerve at the level of the carpal tunnel is the most common entrapment neuropathy which increases dramatically in patients with diabetes. Neuromuscular ultrasound provides extensive diagnostic information and has proved itself as a useful complementary test to electrodiagnostic examinations in cases involving median nerve neuropathy. It often happens that the cause of nerve entrapment and neuropathy are variants of several anatomical structures along the course of the median nerve. It is important to be aware and report such anatomical variations of the median nerve in order to avoid damaging the nerve during surgical treatment. Despite the frequently documented abnormalities in the pathway of the brachial plexus and the median nerve, the anatomical variations are unusual to see and are rarely reported. Moreover, there are variations that do not fit under any of the classifications described in the literature.

Comparison of Threshold and Tolerance Nociceptive Withdrawal Reflexes in Horses.

Simple SummaryNociception is the physiological basis of the complex experience of pain. An established model for its quantification in equine studies is based on the nociceptive withdrawal reflex evoked by electrical stimulation of a sensory nerve. The reflex is recorded via electromyography and it is common to determine the threshold at which a nociceptive-specific reflex activity can be observed. In the present study, the classical methodology was expanded for a deeper understanding of the physiology of nociceptive reflexes in horses. First, for each individual horse, a threshold was determined as the minimal stimulation intensity able to evoke a nociceptive withdrawal reflex. Second, the stimulation intensity was stepwise increased up to tolerance, which was defined as the stimulus that is able to elicit the maximal tolerable behavioral reaction. The characteristics of the reflex activity on the electromyographic records were compared for threshold and tolerance stimulation intensities. At tolerance, the reflex became faster and wider than at threshold, indicating that either a spinal summation mechanism or the recruitment of faster sensory fibers occurs in response to high-intensity noxious stimuli. A novel endpoint (i.e., tolerance) can now be considered when applying the nociceptive withdrawal reflex model in equine studies.The nociceptive withdrawal reflex (NWR) is used to investigate nociception in horses. The NWR threshold is a classical model endpoint. The aims of this study were to determine NWR tolerance and to compare threshold and tolerance reflexes in horses. In 12 horses, the NWR was evoked through electrical stimulation of the digital nerve and recorded via electromyography from the deltoid. Behavioral reactions were scored from 0 to 5 (tolerance). First, the individual NWR threshold was defined, then stimulation intensity was increased to tolerance. The median NWR threshold was 7.0 mA, whereas NWR tolerance was 10.7 mA. Upon visual inspection of the records, two main reflex components R1 (median latency 44 ms) and R2 (median latency 81 ms) were identified at threshold. Increasing stimulation intensity to tolerance led to a significant increase in the amplitude and duration of R1 and R2, whereas their latency decreased. At tolerance, a single burst of early, high-amplitude reflex activity, with a median latency of 39 ms, was detected in 15 out of 23 stimulations (65%). The results of this study suggest that (1) it is feasible to determine NWR tolerance in horses and (2) high-intensity stimuli initiate ultrafast bursts of reflex activity, which is well known in practice and has now been quantified using the NWR model.

Neuroprotective properties of ethanolic extract of Citrus unshiu Markovich peel through NADPH oxidase 2 inhibition in chemotherapy-induced neuropathic pain animal model.

The present study aimed to determine the antioxidant effect of Citrus unshiu Markovich (CUM) extract in neuronal cell lines under oxidative stress and to investigate the effect of chemotherapy-induced peripheral neuropathy (CIPN) on the nociceptive response in a preclinical mice model. We tested the inhibition of H2 O2 in Neuro2A cells treated with CUM. Experimental animals were treated with oxaliplatin to induce CINP, and then administered oral CUM for 4 weeks in order to observe the effect of CUM. Animals were evaluated weekly for thermal hyperalgesia and digital motor nerve conduction velocity (NCV). Lumbar dorsal root ganglia (DRG) isolated from each animal were evaluated through immunochemical and western blot analysis for nerve damage, inflammatory response, and expression of redox signaling factors. The main mechanisms were determined to be decreased inducible nitric oxide synthase (iNOS) production due to the inhibition of NADPH oxidase 2 (NOX2). To determine the functional role of NOX2 in CINP, we administrated CUM into NOX2-deficient mice with neuropathic pain. Therefore, we suggest that CUM controls the expression levels of inflammatory factors in CINP via NOX2 inactivation. This study demonstrated that a complementary medicine such as CUM might be a potential novel therapeutic agent for the treatment of CINP.

First dorsal metacarpal artery flap with dorsal digital nerve with or without dorsal branch of the proper digital nerve produces comparable short-term sensory outcomes

BackgroundThe first dorsal metacarpal artery flap, including dorsal digital nerves with or without dorsal branches of the proper digital nerves, can be used to reconstruct thumb pulp defects with good results. However, it is still unclear whether there are differences in the sensory outcomes between preserving or not preserving the dorsal branches of the proper digital nerves.MethodsThis retrospective cohort study included 137 thumb pulp defect patients who underwent first dorsal metacarpal artery flap reconstruction procedure from October 2015 to June 2019. Patients were divided into two groups according to whether the dorsal branches of the proper digital nerves were preserved. In the non-preservation group (n = 80), the dorsal digital nerves were included in the flap for sensory reconstruction. In the preservation group (n = 57), the dorsal digital nerves and the dorsal branches of the proper digital nerves of the index finger were included in the flap. The stump of the proper digital nerves in the defect was coaptated to the donor nerves of the flap using the end-to-end fashion. At the last follow-up, static two-point discrimination, Semmes–Weinstein monofilament scores, pain, cold intolerance of the reconstructed finger, and patient satisfaction in both groups were compared.ResultsAll patients were followed up for at least 17 months. No significant differences were found regarding pain of thumb pulp, static two-point discrimination, Semmes–Weinstein monofilament score, cold intolerance in the injured finger, and patient satisfaction. The non-preservation group presented slightly shorter operative times (p < 0.05).ConclusionThere are no differences at 2 years in postoperative clinical outcomes when dorsal digital nerves are used to reconstruct flap sensation regardless of preservation of the dorsal branches of the proper digital nerves in the first dorsal metacarpal artery flap.Level of evidence: Level III, retrospective comparative study.

Irreducible Dislocation of Thumb Interphalangeal Joint: A Case Report

Closed dislocation of thumb Interphalangeal (IP) joint is rare, due to the inherent stability of the thumb IP joint. The interposition of the volar plate, flexor pollicis longus, sesamoids, and digital nerves can treat the joint closed reduction. In this study, we report a case of three-week-old irreducible closed dislocation of thumb IP joint in a 33-year-old woman. We planned to perform open reduction surgery using a dorsal approach on the IP joint and the ulnar side opening. The volar plate was interposed in the joint. Seven months after surgery, the patient achieved 0-45 degrees of IP range of motion. No sign of degenerative joint changes on the x-ray images was observed in the final visit. This study suggests the high probability of open reduction for these injuries and recommends the use of dorsal approach, excluding the complications of volar approach.

A Novel Alaska Pollock Gelatin Sealant Shows Higher Bonding Strength and Nerve Regeneration Comparable to That of Fibrin Sealant in a Cadaveric Model and a Rat Model

A novel biocompatible sealant composed of Alaska pollock-derived gelatin (ApGltn) has recently shown good burst strength and biocompatibility in a porcine aorta. The purpose of this study was to investigate the bonding strength and biocompatibility of the ApGltn sealant in transected digital nerves of fresh frozen cadavers and in the sciatic nerves of a rat model. Eighty human digital nerves of fresh frozen cadavers were transected for biomechanical traction testing. They were treated with four surgical interventions: (1) suture plus ApGltn sealant; (2) suture; (3) ApGltn sealant; and (4) fibrin sealant. Forty-three sciatic nerves of male Wistar rats were used for functional and histopathologic evaluation. They were treated with six surgical interventions: (1) suture plus ApGltn sealant; (2) suture; (3) ApGltn sealant; (4) fibrin sealant; (5) resection with a 5-mm gap (10 rats per group); and (6) sham operation (three rats). Macroscopic confirmation, muscle weight measurement, and histopathologic findings including G-ratio were examined 8 weeks after the procedure. The maximum failure load of the ApGltn sealant was significantly higher than that of a fibrin sealant (0.22 ± 0.05 N versus 0.06 ± 0.04 N). The maximum failure load of the ApGltn sealant was significantly lower that of suture plus ApGltn sealant (1.37 N) and suture (1.27 N). Functional evaluation and histologic examination showed that sciatic nerves repaired with ApGltn sealant showed similar nerve recovery compared to repair with the suture and fibrin sealant. The ApGltn sealant showed higher bonding strength and equal effect of nerve regeneration when compared with the fibrin sealant.

The Impact of Digital Nerve Injury on the Outcome of Flexor Tendon Tenolysis: A Retrospective Case-Control Study.

Tenolysis is an established treatment for flexor tendon adhesions at the hand. Concomitant finger nerve injuries with incomplete reinnervation may negatively influence outcomes. This study investigates the impact of finger nerve injuries on outcomes of flexor tendon tenolysis. A retrospective pair-matched study was conducted, including patients undergoing tenolysis for flexor tendon adhesion after primary repair of isolated superficial and deep flexor tendon injury and both finger nerves (test group [TG]). These were compared with patients (control group [CG]) with similar injuries without affection of nerves and pair-matched in age, zone of injury and follow-up. Patients' demographics, finger sensitivity, total active range of motion (TAM) before and after tenolysis and complications were retrieved. For both study groups, 10 patients each were included in this study. There were no significant differences regarding patients' demographics and follow-up. Mean follow-up was 37 (CG) and 41 (TG) months. Total active range of motion was preoperatively 81 ± 47° (CG) and 68 ± 54° (TG) and reached postoperatively 125 ± 57° (CG) and 79 ± 43° (TG). Hence, TAM improvement was significantly higher in patients without nerve damage (58 ± 16 vs 21 ± 11%; P > 0.05). Tendon ruptures occurred significantly more frequent in patients with nerve injury (n = 0.4 ± 0.52) compared with patients of the CG (n = 0; P < 0.05). This study shows that finger nerve injury with incomplete recovery after combined flexor tendon and nerve injuries of the finger negatively influences the outcomes of flexor tendon tenolysis.

Complex Dorsal Metacarpophalangeal Dislocation of Index Finger- A case report

Complex posterior metacarpophalangeal dislocations of the long fingers are rare, typically caused by entrapment of the volar plate within the joint space. They require surgical reduction to release the soft tissues interposed between the metacarpal head and the proximal phalanx. but there is an operative risk of digital nerve injury because of intricate displacement of the normal anatomy. We report the case of a 30-year-old patient who presented to the emergency department at the second day after his trauma with a complex posterior metacarpophalangeal dislocation of the right index finger. After failure of the closed reduction attempt, the dislocation was reduced surgically by an volar approach. The neurovascular bundle has been identified and carefully removed. The volar plate has been reduced, resulting in reduction of the dislocation. The volar plate has been completely repaired. At six weeks, all the range of motion of the MCP and other joints of the index finger had been found. At the last follow-up, the joint was still stable. Different techniques are described in the literature for the reduction of the complex posterior dislocations of long fingers, but the volar approach remains the best for palmar plate reduction and its full repair, which may decrease the risk of late instability.

Epineural Methylene Blue Injection May Aid Localization of Digital Nerves in Dupuytren’s Surgery

Background: In Dupuytren’s surgery, limited fasciectomy is still the gold-standard treatment. A relatively high risk of iatrogenic nerve injury has been observed especially when the spiral cords of the Dupuytren’s tissue pull digital nerves away from their normal anatomical location. Intraoperative neural marking could facilitate locating the potentially displaced nerves. Hence, surgery could be undertaken more quickly with a lower risk of iatrogenic nerve injury. Objectives: We hypothesize that digital nerves may be stained with methylene blue (MB) in vivo providing a visual aid to distinguish them from Dupuytren’s tissue. We aim to (a) test an in vivo nerve staining technique using MB in a rat sciatic nerve model and to (b) assess the safety of epineural MB injection. Methods: Three experiments were performed: first, the effects of (a) sham surgery, (b) epineural needle insertion, and (c) 40 μL epineural saline injection were tested in the rat sciatic nerve. Second, we determined the (a) histoanatomical localization of the epineurally injected 40 µL 1 m/m% MB stock solution and (b) we tested which saline dilution (i.e., 1:40, 1:80, and 1:160) of the stock solution does provide optimal blue color upon 40 µL epineural injection. Third, the functional and morphological effect of 40 µL 1:80 diluted MB injection was compared with that of saline, injected into the contralateral sciatic nerve. The functional effects were tested by assessing the pain threshold by using a dynamic plantar esthesiometer (DPA) and by examination of the animal’s gate and paw posture. Sciatic nerves were subjected to histological examination and morphometry to test structural damage. Results: Neither epineural needle insertion nor saline injection caused any functional or morphological changes. Histological examination revealed that the MB stained the epineural compartment. Epineural injection of 40 μL 1:80 diluted MB into the sciatic nerve stained an 18.18-mm segment of the nerve distal to the puncture point. DPA revealed unchanged pain threshold values on the plantar surface of the limbs. Normal gait and foot posture suggested normal motor functions in all groups. No histological changes were seen in the stained nerves, and the nerve fiber density remained unchanged. Conclusion: We demonstrated that in vivo nerve staining with MB is a suitable method to mark nerves without causing detectable negative effect to the stained nerve. Human trials are required to prove the efficacy of the technique in Dupuytren’s disease.