Surgical and technological advances in the management of upper limb amputees

Building a Multidisciplinary Clinic Dedicated to Upper-Extremity Limb Loss

Complete care of the patient with upper limb loss mandates a long-term, multifaceted approach. Increased functionality and quality of life require collaborative efforts between the patient's surgeon, prosthetist, hand therapists, mental health professionals, and peers. An individual surgeon may find that initiating and maintaining a practice offering total integrated treatment for upper-extremity amputees is a formidable task, but with specific, actionable recommendations, the process can be demystified. The upper-extremity surgeon must be facile with operative techniques such as targeted muscle reinnervation (TMR), regenerative peripheral nerve interface (RPNI), and soft tissue reconstruction and focus on team recruitment strategy and promotion of the clinic within the community. Consistent communication and team decision-making shape each patient's preoperative and postoperative course. We aim to relay effective interventions at each step of recovery from each clinic member and describe clinic workflow designed to reinforce holistic care. We present a blueprint for creating a functional and comprehensive multidisciplinary center for patients with upper-extremity limb loss for those providers interested in providing care, but who are missing the logistical roadmap for how to do so.

Impact of Timing of Targeted Muscle Reinnervation on Pain and Opioid Intake Following Major Limb Amputation

BACKGROUND

Targeted muscle reinnervation (TMR) has been shown to play an important role in managing neuromas. However, the impact of the timing of TMR on pain visual analogue scale (VAS) scores or patient opioid use has not been thoroughly explored. We hypothesized that TMR performed acutely would lead to lower VAS scores and decreased opioid intake.

METHODS

Prospectively collected data from an amputation registry at a single institution were utilized to identify patients who underwent TMR. Acute TMR was defined as TMR performed within 1 month of the major limb amputation. Primary outcomes included VAS pain scores and patient-reported opioid consumption.

RESULTS

In all, 25 patients (26 limbs) were identified in the acute group, and 18 patients (18 limbs) were identified in the delayed group. At intermediate follow-up (between 4 and 8 months postoperatively) and at final follow-up, the average pain VAS score in the delayed TMR group was significantly higher than that in the acute group (5.2 vs. 1.9 at intermediate P = .01 and 6.2 vs. 1.9 at final P = .002). In all, 84% of the amputees overall were not consuming opioid medications at the time of final follow-up (79% acute, 88% delayed, P = .72). There were no statistically significant differences in opioid consumption between the acute and delayed group at intermediate follow-up (P = .35) or at final follow-up (P = .68).

CONCLUSIONS

TMR is an effective procedure to reduce pain following major limb amputation. Patients with TMR performed acutely had significantly lower VAS pain scores at both intermediate and final follow-up than patients with TMR performed in a delayed setting.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic II.

CAN TEMPORARY ARTERY CATHETERIZATION EXTEND LIMITS OF ISCHEMIA TIME FOR MACROREPLANTATION?

We observe delayed referrals to appropriate Microsurgery Unit and definitive treatment of traumatic limb amputations. Cases with wrist proximal amputations have a deadline for surgical replantation as these configure life-threatening injuries.

Objective

To analyze patients with traumatic proximal wrist upper limb amputations with prolonged ischemic time who underwent temporary artery catheterization to assess stump viability and results.

Methods

A case-series study including all patients with a proximal wrist upper limb amputation and a cold ischemic time equal to or above six hours from 2017 to 2021.

Results

In total, two surgeons operated eight patients who had experienced forearm amputation injuries. Median ischemia time totaled eight hours. All patients required additional surgeries, most commonly split-thickness skin graft or fixation revision (three patients). This study obtained five successful macroreimplantations. The mean cold ischemia time was longer in the group with successful macroreimplantations (7.4 hours) than of the unsuccessful group (9 hours).

Conclusion

Macroreplantations require immediate referral to microsurgery and, although temporary artery catheterization helps surgical decision making, the technique seems to fail to influence outcomes. Level of Evidence IV, Retrospective Case Series.

Reconstruction of oncologic upper extremity defects with fibula free flaps has high union rates and excellent functional outcomes

BACKGROUND

Limb salvage has better functional outcomes than amputation in the upper extremity. This can however be challenging after bony tumor resections.

METHODS

This is a retrospective case series of patients who underwent humerus, ulna, or radius reconstruction with a fibula free flap. Data were collected on demographics, oncologic history, surgical details, and complications. Functional outcome measures included the patient's ability to perform activities of daily living (ADL), presence of pain, and musculoskeletal tumor society (MSTS) score.

RESULTS

Over a 25-year period, 38 reconstructions were performed. The flap success rate was 97.5%. Bony union was obtained in 19 of 19 (100%) forearm reconstructions and in 15 of 19 (79%) humerus reconstructions (p = 0.10). All 19 forearm reconstruction patients and 18/19 humerus reconstruction patients were able to perform ADLs with no pain or only occasional pain. The MSTS scores were not significantly different between the humerus and forearm cohorts (27.1 vs. 27.3, p = 0.68). Functional outcomes were significantly better in limbs that achieved union (p < 0.001). Recipient and donor site complications occurred in 10 (26.3%) and 5 (13%) patients, respectively.

CONCLUSIONS

Oncologic upper-extremity reconstruction with fibula free flaps has excellent functional outcomes. Bone union is a predictor of superior limb function.

Activities of daily living in lower limb amputees with a bone-anchored prosthesis: a retrospective case series with 24 months' follow-up

BACKGROUND AND PURPOSE

Little is known about the activities of daily living (ADL) of patients with a bone-anchored prosthesis (BAP). We aimed to objectively measure ADL without and with BAP during standard care of follow-up. Our secondary aim was to measure mobility and walking ability.

PATIENTS AND METHODS

Patients aged 18-99 years who underwent surgery for transfemoral or transtibial BAP between September 11, 2017, and February 11, 2021, were eligible for inclusion in this retrospective case series of patients with socket prosthesis. ADL was measured with a continuous recording activity monitor (hours [h]) before surgery, and at 6, 12, and 24 months with BAP. Mobility and walking ability were assessed by the Timed Up and Go test (TUG) (seconds [s]) and 6 Minute Walk Test (6MWT) (meters [m]), respectively.

RESULTS

48 of the 57 eligible patients provided informed consent and were included. Their age was 59 (1st quartile to 3rd quartile 51-63) years. Total daily activity before BAP was 1.6 h (0.82-2.1) and increased to 2.1 h (1.4-2.5) at 6, 2.0 h (1.5-2.7) at 12, and 2.7 h (2.0-3.3) at 24 months with BAP. Daily walking increased from 1.3 h (0.79-1.9) before BAP to 1.8 h (1.6-2.3) at 6, to 1.7 h (1.2-2.4) at 12, and 2.0 h (1.6-2.6) at 24 months. Median TUG decreased from 12 s (9.1-14) before BAP to 8.9 s (7.7-10) at 24 months. Mean 6MWT increased from 272 m (SD 92) before BAP to 348 m (SD 68) at 24 months.

CONCLUSION

Objective measurements on ADL positively changed in patients with BAP. This effect was also seen in mobility and walking ability at 24 months.

Upper Extremity Prosthetics: Current Options and Future Innovations

Major upper extremity amputations can have a considerable impact on patients' lives, altering their ability to independently perform activities of daily living and leading to changes in occupations and hobbies. Although upper extremity prosthetics have existed for millennia, recent advances have improved prosthetic motor control and sensory feedback, leading to increased overall satisfaction. The goal of this article was to describe the current options that exist for upper extremity prosthetics and explore the recent advances and future directions in prosthetic technology and surgical techniques.

Targeted muscle reinnervation in upper extremity amputation in military hand surgery: A systematic review

INTRODUCTION

Targeted Muscle Reinnervation (TMR) is a surgical technique utilized to alleviate post-amputation neuroma pain, reduce reliance on narcotic pain medication, and enhance control of prosthetic devices. Motor targets for upper extremity TMR vary depending on injury patterns and amputation levels, with conventional transfer patterns serving as general guides. This study aims to summarize the common patterns of TMR in transradial and transhumeral amputations, focusing on anatomic and surgical considerations.

METHODS

A comprehensive systematic review of TMR literature was conducted by two independent physician reviewers (M.H.A. and D.M.G.R.) to identify the prevailing motor targets, while considering injury patterns and amputation levels.

INCLUSION CRITERIA

1) TMR techniques, outcomes, or advancements; 2) Original research, systematic reviews, meta-analyses, or clinical trials; 3) Peer-reviewed journal articles or reputable conference proceedings.

EXCLUSION CRITERIA

non-English resources, editorials, opinion pieces, and case reports. The databases utilized include MEDLINE (PubMed), EMBASE (Scopus) and Cochrane CENTRAL, last searched 01APR2023.

RESULTS

The reviewed literature revealed multiple motor targets described for upper extremity TMR out of our included 51 studies. However, the selection of motor targets is influenced by the availability of viable options based on injury patterns and amputation levels. Conventional transfer patterns provide useful guidance for determining appropriate motor targets in transradial and transhumeral amputations.

DISCUSSION

TMR has played a significant role in military medicine, particularly in addressing the impact of blast-related injuries. The energy associated with such injuries often results in substantial soft tissue defects, higher amputation levels, and increased post-amputation pain. TMR, in conjunction with advancements in prosthetic technology and ongoing military research, offers improved outcomes to help achieve the goals of active-duty service members. The capabilities and applications of TMR continue to expand rapidly due to its high surgical success rate, technological innovations in prosthetic care, and favorable patient outcomes. As technology evolves to include implantable devices, osseointegration techniques, and bidirectional neuroprosthetic devices, the future of amputation surgery and TMR holds immense promise, offering innovative solutions to optimize patient outcomes. It is important to note, this review was limited to the data available in the included resources which was mostly qualitative; thus, it did not involve primary data analysis.

Clinical effectiveness of the Ganga Hospital Open Injury Severity Score for limb salvage versus amputation in patients with complex limb injuries : a systematic review and meta-analysis

AIMS

Clinical management of open fractures is challenging and frequently requires complex reconstruction procedures. The Gustilo-Anderson classification lacks uniform interpretation, has poor interobserver reliability, and fails to account for injuries to musculotendinous units and bone. The Ganga Hospital Open Injury Severity Score (GHOISS) was designed to address these concerns. The major aim of this review was to ascertain the evidence available on accuracy of the GHOISS in predicting successful limb salvage in patients with mangled limbs.

METHODS

We searched electronic data bases including PubMed, CENTRAL, EMBASE, CINAHL, Scopus, and Web of Science to identify studies that employed the GHOISS risk tool in managing complex limb injuries published from April 2006, when the score was introduced, until April 2021. Primary outcome was the measured sensitivity and specificity of the GHOISS risk tool for predicting amputation at a specified threshold score. Secondary outcomes included length of stay, need for plastic surgery, deep infection rate, time to fracture union, and functional outcome measures. Diagnostic test accuracy meta-analysis was performed using a random effects bivariate binomial model.

RESULTS

We identified 1,304 records, of which six prospective cohort studies and two retrospective cohort studies evaluating a total of 788 patients were deemed eligible for inclusion. A diagnostic test meta-analysis conducted on five cohort studies, with 474 participants, showed that GHOISS at a threshold score of 14 has a pooled sensitivity of 93.4% (95% confidence interval (CI) 78.4 to 98.2) and a specificity of 95% (95% CI 88.7 to 97.9) for predicting primary or secondary amputations in people with complex lower limb injuries.

CONCLUSION

GHOISS is highly accurate in predicting success of limb salvage, and can inform management and predict secondary outcomes. However, there is a need for high-quality multicentre trials to confirm these findings and investigate the effectiveness of the score in children, and in predicting secondary amputations.Cite this article: Bone Joint J 2023;105-B(1):21-28.

Regenerative Peripheral Nerve Interfaces Effectively Prevent Neuroma Formation After Sciatic Nerve Transection in Rats

Objective

The disordered growth of nerve stumps after amputation leading to the formation of neuromas is an important cause of postoperative pain in amputees. This severely affects the patients' quality of life. Regenerative peripheral nerve interfaces (RPNIs) are an emerging method for neuroma prevention, but its postoperative nerve growth and pathological changes are yet to be studied.

Methods

The rat sciatic nerve transection model was used to study the effectiveness of RPNI in this experiment. The RPNI (experimental) group (n = 11) underwent RPNI implantation after sciatic nerve transection, while the control group (n = 11) only underwent sciatic nerve transection. Autotomy behavior, ultrasonography, and histopathology were observed for 2 months postoperatively.

Results

Compared to the control group, the incidence and size of the neuromas formed and the incidence and extent of autotomy were significantly reduced in the RPNI group. The axon density in the stump and degree of stump fibrosis were also significantly reduced in the RPNI group.

Conclusion

RPNI effectively prevented the formation of neuromas.

Mechanical Design Optimization of Prosthetic Hand's Fingers: Novel Solutions towards Weight Reduction

From the mechanical function of grabbing objects to the emotional aspect of gesturing, the functionality of human hands is fundamental for both physical and social survival. Therefore, the loss of one or both hands represents a devastating issue, exacerbated by long rehabilitation times and psychological treatments. Prosthetic arms represent an effective solution to provide concrete functional and esthetical support. However, commercial hand prostheses still lack an optimal combination of light weight, durability, adequate cosmetic appearance, and affordability. Among these aspects, the priority for upper-limb prosthesis users is weight, a key parameter that influences both the portability and the functionality of the system. The purpose of this work is to optimize the design of the MyHand prosthesis, by redesigning both the proximal and distal finger and thumb in light of finding an optimal balance between weight reduction and adequate stiffness. Starting from elastic–plastic numerical models and experimental tests on obsolete components, analyzed under the worst loading condition, five different design solutions are suggested. An iterative topology optimization process locates the regions where material removal is permitted. From these results, 2 mm geometrical patterns on the top surface of the hand prosthesis appear as the most prominent, preventing object intrusion.