Digital Nerve Repair Research Articles

Long-term subjective and objective outcomes after digital nerve repair: a cohort study.

Digital nerve injuries are common, but few studies report long-term effects for the individual. The primary aim of this matched-pairs study comparing digital nerve injuries in border digits or central fingers was to investigate hand function 3-10 years after digital nerve repair, assessed using the Mini Sollerman test in 86 patients. Secondary outcomes were sensory function, range of motion, grip strength and patient-reported measures. No significant difference was seen in hand function between the groups, except for lower grip strength in patients with central finger injury. Tactile discrimination was achieved in 87%, with best results among participants aged less than 44 years. Touch perception was measurable in 99%. No statistically significant differences in sensory function were found between the groups. Patient-reported disability was low, with median Quick Disabilities of the Arm, Shoulder and Hand score of 5, but half of the patients reported neuropathic pain. Numbness and cold sensitivity were the symptoms graded worst after digital nerve injury.Level of evidence: III.

Robotic-assisted microsurgery using the MUSA-robot: evaluation of the learning curve in three clinical pilot trials

Aim: Current microsurgical procedures are limited by the physiological tremor and dexterity of the surgeon. The MicroSurgical Assistant (MUSA, Microsure), the world’s first robotic platform for (super)microsurgery can aid in resolving issues encountered during microsurgery. This study presents an overview of the operating times and Structured Assessment of Microsurgery Skills (SAMS) scores to assess the duration and quality of microsurgical anastomoses for three microsurgical procedures currently performed using the MUSA. Methods: This study integrates data from one ongoing randomized controlled trial focusing on robotic-assisted lymphaticovenous anastomosis, along with findings from two separate prospective pilot studies concerning digital nerve repair and free tissue transplantation. SAMS scores and time needed per anastomosis were used to evaluate the quality and learning curve of the MUSA-assisted procedures. Results: Thirty-five robotic-assisted procedures were analyzed, including 18 lymphaticovenous anastomoses, 9 digital nerve repairs, and 8 free tissue transplantations. All procedures showed a trend of a decrease in the time needed to perform the procedure. Moreover, the mean overall SAMS scores for all three procedures were rated above ‘satisfactory’, with all procedures demonstrating a consistent trend of increasing SAMS scores over time. Conclusion: The evaluation of anastomosis’ quality in the initial cohorts of patients undergoing robotic-assisted microsurgery using MUSA indicates satisfying outcomes across all three types of procedures. The reduction in anastomosis time and the improvement in SAMS scores imply an ongoing learning process among the operating surgeons. Subsequent reports are expected to provide information on reaching a plateau phase in procedural efficiency.

UK Trainee Experience with WALANT - An Audit of 102 Cases.

Background: WALANT has gained much popularity in recent years, especially with COVID-19. However, a recent survey of the American Society for Surgery of the Hand membership (i.e. attendings/consultants) showed that only 17% were exposed to WALANT during residency or fellowship training. There is much interest in WALANT from trainees, but interpretation of the type and volume to be administered is highly varied. Methods: The aims of this study were (1) to survey a group of plastic surgery trainees in the UK about their knowledge of WALANT formulas, and (2) to compare trainee logbook records of WALANT procedures (if available) with published data from the UK. Results: All trainees were familiar with the 'standard' WALANT formula (1% lidocaine, 1:100,000 adrenaline ± 8.4% NaHCO3) described by Lalonde. However, because of local formularies, rather than 1:100,000 adrenaline, all used 1:200,000 adrenaline as it comes premixed in the UK. Other formulas used by UK trainees included 0.5% bupivacaine + 1:200,000 adrenaline, and mixing 1% lidocaine + 1:200,000 adrenaline with 1% lidocaine 1:1. In comparing available trainee WALANT records with published UK data, the average volume of WALANT used was 6.6 mls in the current study versus 12.9 mls for similar procedures (wound debridement and skin closure ± local flap, digital nerve repair, fingertip reconstruction, thenar injuries, phalangeal fracture and single digit extensor repair); specifically, for single digit flexor tendon repairs, this was 10 mls versus 16.3 mls. Conclusions: While the British Society for Surgery of the Hand (BSSH) have developed official guidance for the use of WALANT in the UK, it appears there remains much variation in interpretation and hence, application. Comparison of trainee logbook records of common hand surgery procedures suggests that most can be done with much less WALANT administered than previously reported, with safe and reproducible results. Level of Evidence: Level IV (Therapeutic).

Cost Comparison of Digital Nerve Repair Techniques.

Direct cost comparison of nerve allograft with other techniques for repairing short digital nerve gaps are lacking. This study compares the costs of various techniques for digital nerve repair, anticipating significant cost increases for allograft implants. The State Ambulatory Surgery and Services Database for Florida, New York, and Wisconsin from 2015-2020 was used. Patients with primary repair, short autograft, conduit, and allograft were compared along total, surgical supply, operating room (OR), and anesthesia charges. Among 5,009 patients were 2,967 primary nerve repairs (59.2%), 77 autografts (1.5%), 1,647 conduits (32.9%), and 318 allografts (6.3%). 2,886 patients were male (57.6%) with mean age 40.4 ± 16.3 years. Over the study period, primary repairs decreased (63.9% in 2015 to 56.3% in 2020) while allografts increased significantly (8.8% in 2018 to 12.6% in 2020).Median total charges significantly varied across procedures, with the most expensive being allograft ($35,295), followed by conduit ($25,717), autograft ($24,749), and primary repair ($18,767). On multivariable regression, allograft is significantly more expensive than autograft for total charges by $11,224 (95CI: $4,196-$18,252) and supply charges by $10,484 (95CI: $6,073-$14,896), but not for OR or anesthesia charges. Flexor tendon repair was associated with greater total, OR, and anesthesia charges but similar supply charges. Nerve allograft is the most expensive digital nerve repair technique most likely due to the cost of the implant. To minimize health care expenditure and ensure equitable patient access, surgeons should consider this cost along with clinical factors in choosing digital nerve repair techniques.

The effect of injury area on the success of treatment in digital nerve injury.

The main objective of the current study is to investigate variations in postoperative outcomes that follow digital nerve repair in Zone 1 and Zone 2, respectively. We hope that by carrying out this investigation, we will be able to identify which zone has better sensation recovery and patient-reported outcomes, allowing us to identify the best way of conducting surgery for specific types of injuries. A retrospective cohort study was conducted in patients with digital nerve injuries treated in a designated hand surgery clinic between January 2021 and December 2023. The study was guided by ethical consideration, where all participants gave their informed consent. Surgical interventions involved primary repair, autograft/allograft nerve grafting, nonsurgical approaches, as well as conduit repair in which results were determined using objective measures and patient feedback. Direct repair emerged superior among injuries of Zone 1 and Zone 2 with high success rates and good patient-reported outcomes. In general, injuries in Zone 1 had better sensory recovery than injuries in Zone 2 and this was associated with higher levels of satisfaction. Comparisons using statistical methods confirmed that direct repair outperformed other modalities. More importantly, the comparison of this study shows that repairs in Zone 1 are more successful than those in Zone 2 revealing direct repair as a superior method for digital nerve injuries. The difference is crucial because it suggests that surgical efficiency may depend on where the injury is. This means that direct repair should be given priority over the two zones, although surgeons will need to watch out for challenges related to Zone 2 injuries and adjust their strategies accordingly to obtain the best patient outcomes possible.

Comparison of digital nerve repair techniques: a systematic review

Introduction: Digital nerves are the most injured upper limb peripheral nerves [1]. There are numerous different methods of repair, with no standardised treatment options or guidelines. This systematic review aims to evaluate literature that investigated thebiomechanical strength of digital nerve repairs through varying methods in cadaveric models.Aims/Hypothesis: The aim of the study is to evaluate the literature available for digital nerve repairs and directly compare which surgical method yields the best results. The primary outcome is maximum load to failure of the repaired digital nerve following biomechanical (tensile) strength testing. We postulate that out of all the repair methods, augmentation of repair with fibrin glue or additional conduit will increase the load to failure compared to suture only repair.Methodology: We utilised the PRISMA methodology to conduct the systematic review. The following databases were searched: Embase, Medline, Cochrane, and Web of Science. Studies were reviewed and screened by two researchers following an inclusion and exclusion strategy to retrieve relevant papers.Results: A total of seven papers were included in the final review; these papers reported biomechanical data on cadaveric digital nerve repairs. Due to heterogenicity of methods between papers, a combination of quantitative and qualitative analysis of the results was made.Conclusion: The use of minimal suturing with conduit or glue or both has the ability to increase the maximum load to failure of digital nerve repairs compared to suture only methods. This has additional benefits to decrease the number of sutures required for repair. This thereby reduces potential scarring and inflammation.

Polyethylene Glycol-Mediated Axonal Fusion Promotes Early Sensory Recovery After Digital Nerve Injury: A Randomized Clinical Trial

Background. Peripheral nerve repair is limited by Wallerian degeneration coupled with the slow and inconsistent rates of nerve regrowth. In more proximal injuries, delayed nerve regeneration can cause debilitating muscle atrophy. Topical application of polyethylene glycol (PEG) during neurorrhaphy facilitates the fusion of severed axonal membranes, immediately restoring action potentials across the coaptation site. In preclinical animal models, PEG-fusion resulted in remarkable early functional recovery. Methods. This is the first randomized clinical trial comparing functional outcomes between PEG-fusion and standard neurorrhaphy. Participants with digital nerve transections were followed up at 2 weeks, 1 month, and 3 months postoperatively. The primary outcome was assessed using the Medical Research Council Classification (MRCC) rating for sensory recovery at each timepoint. Semmes-Weinstein monofilaments and static two-point discrimination determined MRCC ratings. Postoperative quality of life was measured using the Michigan Hand Questionnaire (MHQ). Results. Forty-eight transected digital nerves (25 control, 23 PEG) across twenty-two patients were analyzed. PEG-fused nerves demonstrated significantly higher MRCC scores at 2 weeks (OR 16.95, 95% CI: 1.79 – 160.38, p = 0.008) and 1 month (OR 13.40, 95% CI: 1.64 – 109.77, p = 0.009). Participants in the PEG cohort also had significantly higher average MHQ scores at 2 weeks (Hodge’s g 1.28, 95% CI: 0.23 – 2.30, p = 0.0163) and 1 month (Hodge’s g 1.02, 95% CI: 0.04 – 1.99, p = 0.049). No participants had adverse events related to the study drug. Conclusion. PEG-fusion promotes early sensory recovery and improved patient well-being following peripheral nerve repair of digital nerves.

Microsurgical Techniques for Digital Nerve Injuries and Vascular Injuries.

Tension-free end-to-end digital nerve repair or reconstruction under loupe or microscope magnification are surgical treatment options for lacerated digital nerves in patients with multiple injured digits, injuries to the border digits, or injuries to the thumb, with the goal of improved or restored sensation and a decreased risk of painful traumatic neuroma formation. Different techniques for primary repair have been described and include epineurial sutures, nerve "glues" including fibrin-based gels1,2, biologic or synthetic absorbable or nonabsorbable nerve wraps or conduits, or a combination of these materials. Nerve "glues" have demonstrated decreased initial gapping at the repair site3 and an increased tensile load to failure when utilized with a nerve wrap or conduit4,5. When there is a gap or defect in the nerve and primary repair is not feasible, nerve allograft and autograft provide similar results and are both better options than conduit reconstruction6. Concomitant or isolated digital vascular injuries may also be surgically treated with end-to-end repair in a dysvascular digit, with the goal of digit and function preservation. In the absence of complete circumferential injury or complete amputation, redundant or collateral flow may be present. Single digital artery injuries often do not need to be repaired because of the collateral flow from the other digital artery. Digital nerve and vascular injuries are often found in the context of traumatic wounds. In such cases, surgical exploration is often required, with possible surgical extension of the wounds to facilitate identification of the neurovascular bundles. The proximal and distal ends of the transected nerve and/or artery are identified, and the traumatized ends are incised sharply, maintaining as much length as possible to facilitate end-to-end repair, interposition of a graft, and the use of a conduit. The proximal and distal aspects of the nerve and/or artery are appropriately mobilized by dissecting or releasing any scar tissue or soft tissue that may be tethering the structure. The defect is measured in the natural resting position of the digit. Gentle flexion of the digit may be performed to facilitate a primary repair in the setting of very small defects. Primary repair or reconstruction is selected, and an 8-0 or 9-0 nonabsorbable monofilament suture is utilized to anastomose the appropriate structures under magnification with use of a single or double stitch6. A tubular nerve conduit is placed prior to epineurial suturing, or a nerve conduit wrap is applied circumferentially around the repair site and augmented with a fibrin glue. The wound is then irrigated and closed in a standard fashion, as determined by the presence of any soft-tissue or structural injury. Alternatives to primary repair include the use of conduits or autologous or allogenic grafting. Factors that necessitate reconstruction include gapping and poor soft-tissue integrity, which can be related to the mechanism of injury. Alternatives to repair or reconstruction include treatment of the-soft tissue or structural injury without concomitant repair or reconstruction of the damaged digital nerves or vessels. Primary end-to-end repair and reconstruction of digital nerves increases a patient's likelihood of sensation recovery, and arterial repair can preserve a digit and avoid the need for amputation. Sensation in the digits is very important for fine motor skills and interaction with the environment, and it is particularly important for patients who rely on their hands for work and/or recreation. For these reasons, the digital nerves to the border digits, such as the ulnar aspect of the small finger, radial aspect of the index finger, and both digital nerves to the thumb, are given particular attention. Surgical intervention to repair or reconstruct the digital nerves increases the likelihood of recovering pre-injury sensation; however, the chance of complete recovery remains low. A systematic review of the outcomes of digital nerve repair in adults published in 2019 showed that the average percentage of patients who had undergone repair and reported a recovery to Highet grade 4 was 24% (range, 6% to 60%)8. The rate of adverse events was comparable between the operatively and nonoperatively treated patients, with complications including neuromas, hyperesthesia, and infection. The use of a microvascular background material can provide better visualization of the proximal and distal ends while performing the repair.It is important to sharply guillotine the ends of the nerve to freshen up the laceration and provide healthy nerve ends for repair.Repair sutures need to be passed through the epineurium, with care taken not to pass through the nerve fascicles. OR = operating roomPIP = proximal interphalangealPT = prothrombin timePTT = partial thromboplastin time.

Mid-term outcomes of digital nerve injuries treated with Renerve® synthetic collagen nerve conduits: A retrospective single-center study

BackgroundBiodegradable synthetic nerve conduits have become widely used for peripheral nerve injuries. Recently, bioabsorbable collagen conduits filled with collagen fibers (Renerve®) are commercially available in Japan. We investigated the clinical efficacy and safety of Renerve® conduits for digital nerve repair. Patients and methodsWe retrospectively reviewed data of patients who underwent digital nerve repair using Renerve® conduits between August 2017 and February 2022 at our hospital and were followed up for at least 12 months. Seventeen patients (20 nerves) with a median age of 46.5 years (interquartile rage: 26–48 years) were included in the analysis. We analyzed sensory nerve function recovery and residual pain or uncomfortable tingling, as well as safety outcomes. The relationship between nerve defect length and sensory function data was assessed using Spearman's rank correlation. ResultsSensory nerve function at 12 months postoperatively was excellent in six, good in 10, and poor in four nerves, and that at the final follow-up (median period, 24 months; range, 12–30 months) was excellent in nine, good in 10, and poor in one nerve. All nerves with a defect length of <12 mm had excellent or good sensory outcomes. At 12 months postoperatively, the correlation coefficients between nerve defect length and Semmes-Weinstein monofilament test results, static two-point discrimination, and dynamic two-point discrimination were 0.35 (p = 0.131), 0.397 (p = 0.0827), and 0.451 (p = 0.0461), respectively. Residual pain or tingling sensation were observed in four nerves at the final follow-up. No postoperative complications were observed in any of the patients. ConclusionsThis study demonstrated the clinical efficacy and safety of Renerve® conduits for digital nerve repair. Our results will be useful in clinical practice because of the scarcity of real-world data on the use of Renerve® conduits for digital nerve repair.

Precise Monitoring of Returning Sensation in Digital Nerve Lesions by 3-D Imaging: A Proof-of-Concept Study.

Digital nerve lesions result in a loss of tactile sensation reflected by an anesthetic area (AA) at the radial or ulnar aspect of the respective digit. Yet, available tools to monitor the recovery of tactile sense have been criticized for their lack of validity. However, the precise quantification of AA dynamics by three-dimensional (3-D) imaging could serve as an accurate surrogate to monitor recovery following digital nerve repair.For validation, AAs were marked on digits of healthy volunteers to simulate the AA of an impaired cutaneous innervation. Three dimensional models were composed from raw images that had been acquired with a 3-D camera (Vectra H2) to precisely quantify relative AA for each digit (3-D models, n= 80). Operator properties varied regarding individual experience in 3-D imaging and image processing. Additionally, the concept was applied in a clinical case study.Images taken by experienced photographers were rated better quality (p< 0.001) and needed less processing time (p= 0.020). Quantification of the relative AA was neither altered significantly by experience levels of the photographer (p= 0.425) nor the image assembler (p= 0.749).The proposed concept allows precise and reliable surface quantification of digits and can be performed consistently without relevant distortion by lack of examiner experience. Routine 3-D imaging of the AA has the great potential to provide visual evidence of various returning states of sensation and to convert sensory nerve recovery into a metric variable with high responsiveness to temporal progress.

Digital nerve injury: to repair or not?

There are very few studies comparing patients with and without repair after digital nerve injury. It is still controversial whether digital nerve repair is necessary. The aim of this study was to evaluate the long-term clinical outcomes of patients with unilateral isolated digital nerve injury who underwent surgical repair and those who did not. Seventy-four patients with unilateral digital nerve injury were included in the study. Of these, the patients who underwent surgical repair were determined as group A (n = 42), the patients without repair as group B (n = 32), and the groups were divided into subgroups according to injury levels. Results were evaluated with a minimum follow-up of 24months. When the S2PD results were evaluated overall, it was found that those who had digital nerve repair (group A) had significantly better outcomes compared to those without repair (group B) (p = 0.012). When the subgroups were evaluated according to the injury localization, no significant difference was observed at the distal levels, while it was observed that the patients who underwent repair in the proximal levels showed significantly better results (p = 0.003, p = 0.012). In this study, it was seen that there was no difference between the results of repair and non-repair of unilateral nerve injuries distal to the middle level of the middle phalanx, but repair is required in injuries proximal to this level.

A comparative study of digital nerve and digital arterial repairs performed using running versus interrupted suture techniques in finger replantations.

The present study aimed to retrospectively analyze replantations and compared the success rates of different suturing techniques. The data of 54 patients who underwent 82 finger replantations between January 2016 and April 2020 were retrospectively analyzed. Patients who underwent traumatic total finger amputations were included in the study. Arteries were repaired with two techniques, the simple running suture technique and the simple interrupted suture technique. Demographic patient data, comorbidities, operative data, post-operative care, the length of hospital stay, mechanism of injury, and site of injury were recorded. The groups were statistically analyzed. Functional outcomes were evaluated according to the Quick DASH score. A total 54 patients with a mean age of 32.5±18.4 (range 1-75) who underwent finger replantation were included in the study. The mean duration of follow-up was 30.9±16.1 months. The mechanism of injury was guillotine-style injury in 29 (35.4%) fingers, avulsion injury in 15 (18.3%) fingers, and crush injury in 38 (46.3%) fingers. Forty-six fingers were repaired using a simple running suture technique, and 36 fingers were repaired using a simple interrupted suture technique. There was no statistically significant difference in terms of failure between the suture techniques (p=0.569). Further, although there was no statistically significant difference in Quick DASH scores according to the type of trauma in the simple running suture technique group (p=0.109), a comparison could not be made within simple interrupted suture technique group because of the small sample size. There was no statistically significant difference in failure rates between cases with an ischemia duration of <6 h and those with ischemia duration of 6-12 h (p>0.05). No statistically significant difference was found between the groups according to age, body mass index, arterial hypertension, or diabetes mellitus (p>0.05). Statistically significant differences were found in univariate analysis according to surgery time per digit, smokers, or vein repair (p<0.05). In total, 65 (79.3%) out of 82 finger replantations were successful. A total of 17 out of 30 fingers that could not undergo venous repair survived because of treatment with medicinal leeches. Finger replantation is a difficult-to-perform surgical procedure requiring consideration of the surgical indications and the presence of an experienced surgical team. Regardless of the suture technique in finger amputations, performing venous anastomosis after arterial anastomosis is essential to restore circulation.

From replantation to transplantation: The evolution of orthoplastic extremity reconstruction.

For more than six decades, the use of the operating microscope for extremity surgery has led to remarkable advances in the management of orthopedic trauma, tumors, infections, and congenital differences. The microsurgical reconstructive ladder ascends from basic microsurgical procedures such as a digital artery or nerve repair to more complex procedures such as autologous tissue transplantation. Functional muscle transfers, toe-to-hand transfers, and recently vascularized composite allotransplantation are the highest rungs on this ladder that help restore extremity function. The development of the orthoplastic approach over the last three decades simultaneously integrates the principles and practices of both orthopedic surgery and plastic surgery for optimal care and salvage of extremities. Clinical, anatomic, and basic science research in reconstructive microsurgery has resulted in significant improvements in extremity salvage, reconstruction, and restoration.

Muscle-in-Vein Conduits for the Treatment of Symptomatic Neuroma of Sensory Digital Nerves.

Background: Considering the debilitating burden of neuroma resulting in a significant loss of function and excruciating pain, the use of muscle-in-vein conduits (MVCs) for the reconstruction of painful neuroma of sensory nerves of the fingers was assessed. Methods: We retrospectively analyzed 10 patients who underwent secondary digital nerve repair by MVCs. The recovery of sensibility was evaluated by static and moving two-point discrimination (2PDs, 2PDm) and Semmes-Weinstein monofilament testing (SWM). The minimum follow-up was set 12 months after the operation. Results: The median period between trauma and nerve repair was 13.4 weeks (IQR 53.5). After neuroma resection, defects ranged from 10–35 mm (mean 17.7 mm, SD 0.75). The successful recovery of sensibility was achieved in 90% of patients after a median follow-up of 27.0 months (IQR 31.00). The mean 2PDs and 2PDm was 8.1 mm (SD 3.52) and 5.2 mm (SD 2.27), respectively. Assessment by SWM resulted in a mean value of 3.54 (SD 0.69). Reduction in pain was achieved among all patients; eight patients reported the complete relief of neuropathic pain. There was no recurrence of neuroma in any patient. Conclusions: Muscle-in-vein conduits provide an effective treatment for painful neuroma of digital nerves, resulting in satisfactory restoration of sensory function and relief of pain.

Conduit/Wrap Repairs to Digital Nerves Provide Residual Strength After Peak Loading.

Many techniques are used for digital nerve repair, most commonly coaptation by sutures. Nerve repairs must be strong while offering an environment for nerve regeneration. Sutures can damage the nerve and thereby limit growth and regeneration. Sutures can rip and cause sudden catastrophic failure. Fibrin glue and conduit-wraps allow a good environment for growth, but neither provides much strength. A benefit to conduit repair would arise if the repair maintained integrity after the peak load so that the path for regrowth stayed in place. The goal for this study was to determine whether conduit with glue provides continued strength after a maximum load is reached. Digital cadaveric nerves were harvested and repaired with 2 epineurial sutures, conduit, and fibrin glue in all combinations. Tests to failure were performed, gap displacement between nerve ends recorded, and the postpeak load energy to dissociation of the nerve and conduit was calculated. Conduit with glue and 2 sutures at the end had the greatest energy and displacement after the peak load but was not significantly different than conduit with glue and 1 suture. Conduit with glue alone obtained statistically the same displacement as conduit with glue and 2 sutures. Conduit, with or without glue, and 2 sutures was statistically the same as suture only repair for peak load. Conduit/wrap maintains a load capacity and a path for nerve regeneration after the peak. Suture at the ends of conduit, not at the coaptation site, reduces damage at the point of injury.

Prevalence of post-traumatic neuropathic pain after digital nerve repair and finger amputation

Post-traumatic neuropathic pain is a major factor affecting the quality of life after finger trauma and is reported with considerable variance in the literature. This can partially be attributed to the different methods of determining neuropathic pain. The Douleur Neuropathique 4 (DN4) has been validated to be a reliable and non-invasive tool to assess the presence of neuropathic pain. This study investigated the prevalence of neuropathic pain after finger amputation or digital nerve repair using the DN4 questionnaire. Patients with finger amputation or digital nerve repair were identified between 2011 and 2018 at our institution. After a minimal follow-up of 12 months, the short form DN4 (S-DN4) was used to assess neuropathic pain. A total of 120 patients were included: 50 patients with 91 digital amputations and 70 patients with 87 fingers with digital nerve repair. In the amputation group, 32% of the patients had pain, and 18% had neuropathic pain. In the digital nerve repair group, 38% of the patients had pain, and 14% had neuropathic pain. Secondly, of patient-, trauma-, and treatment-specific factors, only the time between trauma and surgery had a significant negative influence on the prevalence of neuropathic pain in patients with digital nerve repair. This study shows that persistent pain and neuropathic pain are common after finger trauma with nerve damage. One of the significant prognostic factors in developing neuropathic pain is treatment delay between trauma and time of digital nerve repair, which is of major clinical relevance for surgical planning of these injuries.

Cold sensitivity, functional disability and predicting factors after a repaired digital nerve injury

To investigate self-reported cold sensitivity and functional disability after a repaired digital nerve injury. We identified 3204 individuals operated with digital nerve repair in the Swedish national quality registry for hand surgery (HAKIR). Patient-reported symptoms, including cold sensitivity and perceived disability, were examined using two questionnaires (HQ-8 and QuickDASH), three and 12 months postoperatively. Patients with diabetes (n = 48; 3%) were identified in the Swedish National Diabetes Register (NDR). Cold sensitivity (scored 0–100) was the most prominent symptom among 1553 included individuals (998 men, 555 women; median age 41 [IQR 27–54] years). In the regression analysis, flexor tendon injury, hand fracture and injury to multiple structures predicted worsened cold sensitivity (6.9, 15.5 and 25.0 points; p = 0.005, 0.046 and < 0.001) at 12 months. Individuals with moderate (30–70) and severe (> 70) cold sensitivity had higher QuickDASH scores at three and 12 months postoperatively than individuals with mild cold sensitivity (6.0 and 5.5; 19.8 and 21.0 points; p = 0.001). Flexor tendon injury, injuries to multiple structures and diabetes had significant effect on QuickDASH scores at three, but not at 12, months postoperatively. Cold sensitivity is common after a digital nerve repair and impacts self-reported disability. A concomitant injury, particularly multiple injuries, predicts postoperative cold sensitivity.

Investigation of Predictors of Successful Replantation of Distal Digits at the Nail Bed Level: The Contribution of Digital Nerve Repair to Survival Rate.

Replantation of amputated digits at the nail bed level is surgically challenging and differs from replantation at a more proximal amputation level. This study aimed to determine the predictors influencing the success rate of fingertip replantation. Overall, 239 digits of 226 patients who underwent replantation surgery from August of 2009 to March of 2020 were considered. A total of 15 independent variables (i.e., sex; age; injured hand; digit; history of smoking; history of hypertension or diabetes; injury mechanism; amputation level; ischemia duration; surgeon's expertise; numbers of repaired arteries, veins, and nerves; and the need for a vein graft) were investigated for their effects on the survival of the replanted digits. Of all 239 digits, 190 (79.5 percent) survived. Univariate analysis indicated that non-crush-avulsion injury, expertise and experience of the surgeon, vein repair, and nerve repair contributed to increasing the survival rate. Binary logistic regression analysis demonstrated that injury mechanism, vein repair, and nerve repair were significant predictive factors. In addition, in non-vein-repaired, blunt cut, or Ishikawa subzone II cases, digital nerve repair contributed significantly to promote the success rate relative to vein-repaired, crush-avulsion-type injury, and subzone I cases. Vein repair, nerve repair, non-crush-avulsion injury, and surgeon's expertise and experience were the predictors for successful replantation. Intraoperative vein and nerve repair are recommended to improve the survival rate of fingertip replantation at the nail bed level. Risk, III.

Discussion: Investigation of Predictors of Successful Replantation of Distal Digits at the Nail Bed Level: The Contribution of Digital Nerve Repair to Survival Rate.

Austin, Texas From the Department of Surgery and Perioperative Care, Dell Medical School at the University of Texas at Austin. Received for publication April 1, 2021; accepted July 16, 2021. Disclosure:The author has no financial interest to declare in the content of this Discussion. Steven L. Henry, M.D., Department of Surgery and Perioperative Care, Dell Medical School at the University of Texas, 1601 Trinity Street, Suite 704D, Austin, Texas 78712, [email protected]

A novel, low-cost digital nerve repair model.

A novel, low-cost digital nerve repair model.