Targeted Muscle Reinnervation Research Articles

Surgical Treatment of Neuropathic Chronic Postherniorrhaphy Inguinal Pain: A Systematic Review and Meta-Analysis

Background/Objectives: Neuropathic chronic postherniorrhaphy inguinal pain (CPIP) is a serious adverse outcome following inguinal hernia repair surgery. The optimal surgical treatment for neuropathic CPIP remains controversial in the current literature. This systematic review aims to evaluate the effectiveness of various surgical techniques utilized to manage neuropathic CPIP. Methods: The electronic databases Medline, Embase, Web of Science, Cochrane Central, and Google Scholar were searched. Inclusion criteria were defined to select studies reporting on the efficacy of surgical interventions in patients with neuropathic CPIP. The primary outcome was postoperative pain relief, as determined by postoperative numerical or nonnumerical pain scores. Results: Ten studies met the inclusion criteria. Three surgical techniques were identified: selective neurectomy, triple neurectomy, and targeted muscle reinnervation. Proportions of good postoperative results of the surgical techniques ranged between 46 and 88 percent. Overall, the surgical treatment of neuropathic CPIP achieved a good postoperative result in 68 percent (95% CI, 49 to 82%) of neuropathic CPIP patients (n = 244), with targeted muscle reinnervation yielding the highest proportion of good postoperative results. Conclusions: The surgical treatment of neuropathic CPIP is generally considered safe and has demonstrated effective pain relief across various surgical techniques. Targeted muscle reinnervation exhibits considerable potential for surpassing current success rates in inguinal hernia repair surgery.

44. Factors Associated With Successful Pain Mitigation Following Primary And Secondary Targeted Muscle Reinnervation In Amputees

44. Factors Associated With Successful Pain Mitigation Following Primary And Secondary Targeted Muscle Reinnervation In Amputees

Acute versus non-acute targeted muscle reinnervation for pain control following major limb amputation: a comparative study

Acute versus non-acute targeted muscle reinnervation for pain control following major limb amputation: a comparative study

D59. The Long-term Postoperative Pain Course Following Primary and Secondary Targeted Muscle Reinnervation in Amputees

D59. The Long-term Postoperative Pain Course Following Primary and Secondary Targeted Muscle Reinnervation in Amputees

Surgical treatment of painful neuroma in amputated and non-amputated patients: does the level of neurotomy affect clinical outcomes?

To compare the outcomes of distal neurotomy (DN) versus proximal neurotomy (PN) for the surgical management of painful neuromas in amputees and non-amputees, whether used in passive or active treatment. A retrospective study was conducted on patients who underwent surgery for painful traumatic neuromas between 2019 and 2022. DN with neuroma excision was performed at the level of the injury or amputation. PN was performed using a separate proximal approach without neuroma excision. Outcomes included a Numerical Rating Scale (NRS) score and Patient-Reported Outcomes Measurement Information System (PROMIS) scores, as well as patients' subjective assessments. A total of 33 patients were included: 17 amputees and 16 non-amputees. They totalized 43 neuromas treated by DN in 21 cases and PN in 22 cases. At the median follow-up time of 13 months, there were significant decreases in all NRS and PROMIS scores in the whole series. The decrease in limb pain scores was not significantly different between groups, except for the decrease in pain interference and patient satisfaction which were higher in the DN group. Sub-group analyses found the same significant differences in amputees. Targeted muscle reinnervation (TMR) was associated with a higher decrease in PROMIS scores. DN seemed to give better results in amputees but there were confusing factors related to associated lesions. In other situations, the non-inferiority of PN was demonstrated. PN could be of interest for treating neuromas of superficial sensory nerves, for avoiding direct revision of a well-fitted stump and in conjunction with TMR.

Management of Superficial and Deep Peroneal Nerve Neuromas with Targeted Muscle Reinnervation in Nonamputees: Operative Technique and Early Outcomes.

Targeted muscle reinnervation (TMR), a surgical technique developed by the senior authors that coapts proximal ends of nerves to distal motor nerves of adjacent muscles, has demonstrated efficacy in the treatment and prevention of neuroma pain. The objective of this study is to describe the surgical technique for TMR of the superficial peroneal nerve (SPN) and deep peroneal nerve (DPN) in nonamputee patients and provide data on postoperative functional outcomes. A single-institution retrospective chart review was performed between March 2018 and April 2021. Patients were de-identified and included if they were nonamputees receiving TMR for pain in the peroneal nerve distribution. Data extracted included demographic information, symptoms before operation, relevant nerve coaptation, peri-, and postoperative complications, and long-term functional outcomes. Of the 19 patients reviewed, 11 patients underwent TMR of the SPN alone: eight had complete resolution of their symptoms; two indicated partial improvement in pain; and one patient had no improvement. Four patients underwent TMR of the DPN alone: two patients had complete resolution of their pain, and two patients had partial improvement with pain. Four patients underwent TMR of both the SPN/DPN: two patients had complete resolution of their symptoms, and two patients were noted to have significant improvement but had persistent pain from prior foot operations. Average follow-up time was 260 days. TMR is a successful technique in the management of SPN and DPN neuroma pain. Our technique revealed excellent clinical outcomes, no procedure-specific complications, and improved subjective pain reports.

Combined Targeted Muscle Reinnervation With Regenerative Peripheral Nerve Interfaces Decreases Long-Term Narcotic Use in Amputees: A Case Control Study.

Combined targeted muscle reinnervation with regenerative peripheral nerve interfaces ("TMRpni") is a recently described nerve management strategy that leverages beneficial elements of targeted muscle reinnervation (TMR) and regenerative peripheral nerve interface (RPNI) techniques. This study aimed to evaluate the effect of TMRpni on long-term opioid consumption after amputation. We hypothesize that TMRpni decreases chronic opioid consumption in amputees. This is a retrospective cohort study of all patients who underwent TMRpni between 2019 and 2021. These patients were age-matched at a 1:1 ratio with a control group of patients who underwent amputation without TMRpni. Statistical analysis was performed using SPSS Version 28.0. Thirty-one age-matched pairs of patients in the TMRpni and control groups were included. At 30 days after surgery, there was no significant difference in number of patients who required an additional refill of their opioid prescriptions (45% vs 55%, P = 0.45) or patients who continued to actively use opioids (36% vs 42%, P = 0.60). However, at 90 days after surgery, there was a significantly lower number of patients from the TMRpni group who reported continued opioid use compared with the control group (10% vs 32%, P = 0.03). This study demonstrates that TMRpni may translate to decreased rates of chronic opiate use. Continued study is indicated to optimize TMRpni techniques and patient selection and to determine its long-term efficacy.

SP58. Targeted Muscle Reinnervation: Factors Predisposing To Successful Pain Score Reduction

SP58. Targeted Muscle Reinnervation: Factors Predisposing To Successful Pain Score Reduction

Targeted muscle reinnervation surgery in a patient with neurofibromatosis type 1

Targeted muscle reinnervation surgery in a patient with neurofibromatosis type 1

A National Analysis of Targeted Muscle Reinnervation Following Major Upper Extremity Amputation.

Post-amputation pain is a debilitating sequela of upper extremity (UE) amputation. Targeted muscle reinnervation (TMR) is a relatively novel treatment that can help prevent pain and improve quality of life. The purpose of this study is to evaluate national trends in the application of immediate TMR following UE amputations.   . An analysis of the Nationwide Inpatient Sample database was conducted from 2016-2019. ICD-10 codes were used to identify encounters involving UE amputation with and without TMR. NIS weights were used to estimate national estimates of incidence. Patient-specific and hospital-specific factors were analyzed to assess associations with use of TMR. A total of 8,945 weighted encounters underwent UE amputation, and of those, only 310 (3.5%) received TMR. The majority of TMR occurred in urban hospitals (>95%). Younger patients (47 vs. 54, p=0.008) and patients located in New England were significantly more likely to receive TMR. There was no difference in total cost of hospitalization amongst patients who received TMR ($55,241 vs $59,027.8, p=0.683) but significantly shorter lengths of hospital stay when receiving TMR versus other management (10.6 vs. 14.8, p=0.012). TMR has purported benefits of pain reduction, neuroma prevention, and increased prosthetic control. Access to this beneficial procedure following UE amputation varies by demographics and geographic region. Given that TMR has not been shown to increase cost while simultaneously decreasing patient length of stay, increased efforts to incorporate this procedure into training and practice will help to ensure equitable care for amputation patients. .

Economic Cost-Benefit Analysis of Nerve Implanted into Muscle versus Targeted Muscle Reinnervation versus Regenerative Peripheral Nerve Interface, for Treatment of the Painful Neuroma.

This study investigated the relative cost utility of three techniques for the management of symptomatic neuromas after neuroma excision: (1) implantation of nerve into muscle, (2) targeted muscle reinnervation (TMR), and (3) regenerative peripheral nerve interface (RPNI). The costs associated with each procedure were determined using Common Procedural Terminology codes in combination with data from the Centers for Medicaid and Medicare Services Physician and Facility 2020 Fee Schedules. The relative utility of the three procedures investigated was determined using changes in Patient-Reported Outcomes Measurement Information System (PROMIS) and Numeric Rating Scale (NRS) pain scores as reported per procedure. The relative utility of each procedure was reported in terms of quality-adjusted life years (QALYs), as is standard in the literature. The least expensive option for the surgical treatment of painful neuromas was nerve implantation into an adjacent muscle. In contrast, for the treatment of four neuromas, as is common postamputation, TMR without a microscope was found to cost $50,061.55 per QALY gained, TMR with a microscope was found to cost $51,996.80 per QALY gained, and RPNI was found to cost $14,069.28 per QALY gained. While RPNI was more expensive than nerve implantation into muscle, it was still below the standard willingness-to-pay threshold of $50,000 per QALY, while TMR was not. Evaluation of costs and utilities associated with the various surgical options for the management of painful neuromas suggest that nerve implantation into muscle is the least expensive option with the best improvement in QALY, while demonstrating comparable outcomes to TMR and RPNI with regard to pain symptoms.

[Bionic Surgery Meets Bionic Reconstruction - First In-human use of Robotic Microsurgery in Targeted Muscle Reinnervation].

Robotic microsurgery is an emerging field in reconstructive surgery, which provides benefits such as improved precision, optimal ergonomics, and reduced tremors. However, only a few robotic platforms are available for performing microsurgical procedures, and successful nerve coaptation is still a challenge. Targeted muscle reinnervation (TMR) is an innovative reconstructive procedure that rewires multiple nerves to remnant stump muscles, thereby reducing neuroma and phantom limb pain and improving the control of bionic prostheses. The precision of surgical techniques is critical in reducing axonal sprouting around the coaptation site to minimise the potential for neuroma formation. This study reports the first use of a microsurgical robotic platform for multiple nerve transfers in a patient undergoing TMR for bionic extremity reconstruction. The Symani robotic platform, combined with external microscope magnification, was successfully used, and precise handling of nerve tissue and coaptation was easily feasible even in anatomically challenging environments. While the precision and stability offered by robotic assistance may be especially useful for nerve surgery, the high economic costs of robotic microsurgery remain a major challenge for current healthcare systems. In conclusion, this study demonstrated the feasibility of using a robotic microsurgical platform for nerve surgery and transfers, where precise handling of tissue is crucial and limited space is available. Future studies will explore the full potential of robotic microsurgery in the future.

Targeted Muscle Reinnervation: Surgical Protocol for a Randomized Controlled Trial in Postamputation Pain.

Over the past decade, the field of prosthetics has witnessed significant progress, particularly in the development of surgical techniques to enhance the functionality of prosthetic limbs. Notably, novel surgical interventions have had an additional positive outcome, as individuals with amputations have reported neuropathic pain relief after undergoing such procedures. Subsequently, surgical techniques have gained increased prominence in the treatment of postamputation pain, including one such surgical advancement - targeted muscle reinnervation (TMR). TMR involves a surgical approach that reroutes severed nerves as a type of nerve transfer to "target" motor nerves and their accompanying motor end plates within nearby muscles. This technique originally aimed to create new myoelectric sites for amplified electromyography (EMG) signals to enhance prosthetic intuitive control. Subsequent work showed that TMR also could prevent the formation of painful neuromas as well as reduce postamputation neuropathic pain (e.g., Residual and Phantom Limb Pain). Indeed, multiple studies have demonstrated TMR's effectiveness in mitigating postamputation pain as well as improving prosthetic functional outcomes. However, technical variations in the procedure have been identified as it is adopted by clinics worldwide. The purpose of this article is to provide a detailed step-by-step description of the TMR procedure, serving as the foundation for an international, randomized controlled trial (ClinicalTrials.gov, NCT05009394), including nine clinics in seven countries. In this trial, TMR and two other surgical techniques for managing postamputation pain will be evaluated.

Similar rates of reoperation for neuroma after transtibial amputations with and without targeted muscle reinnervation.

To compare the rates of revision surgery for symptomatic neuromas in patients undergoing primary transtibial amputations with and without targeted muscle reinnervation (TMR). Retrospective cohort study. Level I trauma hospital and tertiary military medical center. Adult patients undergoing transtibial amputations with and without TMR. Transtibial amputation with targeted muscle reinnervation. Reoperation for symptomatic neuroma. During the study period, there were 112 primary transtibial amputations performed, 29 with TMR and 83 without TMR. Over the same period, there were 51 revision transtibial amputations performed, including 23 (21%) in the patients undergoing primary transtibial amputation at the study institution. The most common indications for revision surgery were wound breakdown/dehiscence (42%, n = 25), followed by symptomatic neuroma 18% (n = 9/51) and infection/osteomyelitis (17%, n = 10) as the most common indications. However, of the patients undergoing primary amputation at the study's institution, there was no difference in reoperation rates for neuroma when comparing the TMR group (3.6%, n = 1/28) and no TMR group (4.0%, n = 3/75) (P = 0.97). Symptomatic neuroma is one of the most common reasons for revision amputation; however, this study was unable to demonstrate a difference in revision surgery rates for neuroma for patients undergoing primary transtibial amputation with or without targeted muscle reinnervation. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Robot-assisted Microsurgery: Lessons Learned from 50 Consecutive Cases

Background: The potential of robot-assisted surgery in plastic and reconstructive surgery remains to be established, especially in free tissue transfer. This prospective study aimed to present our experience and findings from the first 50 consecutive cases of robot-assisted microsurgery using the Symani surgical system. Methods: A prospective database was maintained, recording patient demographics and surgical details for all cases of robot-assisted microsurgery in a large academic institution. All surgeons underwent an intensive training program with the Symani surgical system. Results: A total of 50 patients who underwent robot-assisted microsurgical reconstruction were identified. Free microsurgical tissue transfer was performed in 45 cases, targeted muscle reinnervation in four cases, and lymphovenous anastomoses in a single case. A total of 94 robot-assisted anastomoses and coaptations were performed, (46 venous and 30 arterial anastomoses, 16 nerve coaptations, two lymphovenous anastomoses). Six cases involved perforator-to-perforator anastomoses. Ninety-eight percent of attempted anastomoses were completed using the robot. Size-mismatch anastomoses, seen in 37.8% of cases, took significantly longer. Minor complications occurred in three cases and major in six cases. There were three cases of microvascular compromise requiring revision. One partial flap loss and no complete flap loss occurred. Conclusions: Our study highlights the immense potential of robot-assisted microsurgery, and a feasible and effective modality for various microsurgical procedures, with outcomes comparable to those of conventional microsurgery. Despite challenges, such as increased operating times and higher costs, the technology offers significant advantages, such as enhanced precision and motion scaling. We identify a slow learning curve and a necessity for higher caseloads.

Three Useful Tips and Tricks for Intraoperative Nerve Stimulation.

Disposable handheld nerve stimulators are widely used in peripheral nerve surgery. Such devices stimulate a motor nerve or the motor component of a mixed nerve by applying electrical current to the proximal region, targeting the main nerve trunk. This stimulation then travels along the motor nerve, reaching the distal end to control the corresponding muscle(s). In this study, the authors demonstrate three useful tips and tricks for handheld nerve stimulation during targeted muscle reinnervation and peripheral nerve surgery. The three tips are (1) identification of proximal muscle contraction by retrograde electrical stimulation of a distal sensory nerve; (2) graded stimulation for identifying motor nerves within fibrotic scarred tissue beds or parallel to the major motor/mixed nerve of interest; and (3) proximal stimulation for validation of adequate post-targeted muscle reinnervation coaptation(s).

Jumpy stump syndrome treated by targeted muscle reinnervation (TMR): a case report and review of the literature

Jumpy stump syndrome treated by targeted muscle reinnervation (TMR): a case report and review of the literature

[Prosthetic Fitting Concepts after Major Amputation in the Upper Limb - an Overview of Current Possibilities].

The upper extremity and particularly the hands are crucial for patients in interacting with their environment, therefore amputations or severe damage with loss of hand function significantly impact their quality of life. In cases where biological reconstruction is not feasible or does not lead to sufficient success, bionic reconstruction plays a key role in patient care. Classical myoelectric prostheses are controlled using two signals derived from surface electrodes in the area of the stump muscles. Prosthesis control, especially in high amputations, is then limited and cumbersome. The surgical technique of Targeted Muscle Reinnervation (TMR) offers an innovative solution: The major arm nerves that have lost their target organs due to amputation are rerouted to muscles in the stump area. This enables the establishment of cognitive control signals that allow significantly improved prosthesis control. A selective literature review on TMR and bionic reconstruction was conducted, incorporating relevant articles and discussing them considering the clinical experience of our research group. Additionally, a clinical case is presented. Bionic reconstruction combined with Targeted Muscle Reinnervation enables intuitive prosthetic control with simultaneous movement of various prosthetic degrees of freedom and the treatment of neuroma and phantom limb pain. Long-term success requires a high level of patient compliance and intensive signal training during the prosthetic rehabilitation phase. Despite technological advances, challenges persist, especially in enhancing signal transmission and integrating natural sensory feedback into bionic prostheses. TMR surgery represents a significant advancement in the bionic care of amputees. Employing selective nerve transfers for signal multiplication and amplification, opens up possibilities for improving myoelectric prosthesis function and thus enhancing patient care. Advances in the area of external prosthetic components, improvements in the skeletal connection due to osseointegration and more fluid signal transmission using wireless, fully implanted electrode systems will lead to significant progress in bionic reconstruction, both in terms of precision of movement and embodiment.

Targeted muscle reinnervation in bionic upper limb reconstruction: current status and future directions.

Selective nerve transfers are used in the setting of upper limb amputation to improve myoelectric prosthesis control. This surgical concept is referred to as targeted muscle reinnervation (TMR) and describes the rerouting of the major nerves of the arm onto the motor branches of the residual limb musculature. Aside from providing additional myosignals for prosthetic control, TMR can treat and prevent neuroma pain and possibly also phantom limb pain. This article reviews the history and current applications of TMR in upper limb amputation, with a focus on practical considerations. It further explores and identifies technological innovations to improve the man-machine interface in amputation care, particularly regarding implantable interfaces, such as muscle electrodes and osseointegration. Finally, future clinical directions and possible scientific avenues in this field are presented and critically discussed.

Social media analysis of pain outcomes following targeted muscle reinnervation

AimTMR was developed to improve myoelectric prosthesis control for amputees; however, it has become an area of interest in pain modulation. Studies show evidence that this procedure alleviates chronic pain in amputees. The primary objective of this study is to utilize social media analysis to understand patients’ post-operative pain, satisfaction, and recovery time after TMR. MethodsData was collected from one Facebook group via posts and comments referencing TMR. Posts published between January 1st, 2020, and March 24th, 2023, were analyzed. Data collected included pain prior to surgery, pain in immediate post-op period, and how pain changed after surgery. Results43 individuals commented on their TMR experience. 31 had favorable surgical outcomes, 7 felt surgery worsened their pain or there was not significant change in their pain levels, and the remaining 5 commented during the initial post-operative period. 24 patients described their pain in the immediate post-operative period and 100% said that post-operative pain was worse than chronic pain. Of 28 authors who commented on overall reduction in chronic pain, 24 reported TMR reduced their pain, while 4 had no change or worsened pain. ConclusionsThe 24 patients who reported improvement in chronic pain aligns with current literature suggesting that TMR is a viable treatment option for pain. Current medical management of similar conditions leaves up to 80% of patients unsatisfied with pain control. This analysis supports the evidence that TMR is an effective treatment for patients who are experiencing post-amputation pain.