Management of upper limb amputations

Soft Tissue Management of Partial Hand Amputation

Conventional teaching in the management of partial hand amputations prioritizes residual limb length, often through local, regional, or distant flaps. While multiple options exist to provide durable soft tissue coverage, only a few flaps are thin and pliable enough to match that of the dorsal hand skin. Despite debulking, excessive soft tissues from previous flap reconstructions can interfere with residual limb function, prosthesis fit, and surface electrode recording for myoelectric prostheses. With rapid advances in prosthetic technology and nerve transfer techniques, patients can achieve very high levels of function following prosthetic rehabilitation that rival, or even outpace, traditional soft tissue reconstruction. Therefore, our reconstruction algorithm for partial hand amputations has evolved to the thinnest coverage possible, providing adequate durability. This evolution has provided our patients with faster and more secure prosthesis fitting with better surface electrode detection, enabling earlier and improved use of simple and advanced partial hand prostheses.

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.

[Amputations of fingers and the hand]

Revision amputation, ray amputation and narrowing of the hand can be indicated for pathological alterations of fingers and thumbs due to traumatic, inflammatory or vascular causes but also for functional deficits regarding mobility, sensibility, perfusion, and/or pain. Surgical amputation is considered if reconstructive options are no longer possible, not desired and are no longer meaningful with respect to effort and risks. Patients need to be informed about the expected deficits in function and esthetic appearance due to the amputation in advance. On the other hand, surgical amputations represent a good treatment option, for which the duration of treatment and scope are well estimated. Therefore, they are good options for patients with comorbidities, with concerns about extensive reconstructive surgery and with limited compliance. It is essential to respect anatomical and functional aspects to guarantee favorable surgical results and avoid complications, which might compromise the function of the hand beyond that which is unavoidable. The most frequent complications after creating a stump or ray resection are persistent pain, unstable skin and soft tissue conditions, mobility disorders, disturbing stumps without function, uncontrolled growth of nail remnants and recurrent inflammation.

Indications for amputation after traumatic brachial plexus injury in adults: Case report and review of new prosthetic technologies

Hand amputation can be discussed after traumatic brachial plexus injury when the patient's hand is non-functional, painful and/or insensitive. That indication is more common in English-speaking countries than in European or Latin countries. New prostheses are now on the market and can be used after hand amputation to improve the functional prognosis in well-selected patients. A 26-year-old male was involved in a road accident in January 2016. He had a traumatic brachial plexus injury and underwent nerve surgery to restore the biceps brachii and triceps brachii. One year after nerve transfer, his hand was insensitive and non- functional. After multidisciplinary consultation, it was decided to amputate his hand to replace it with a myoelectric prosthesis. Shoulder subluxation pain and complications associated with an insensitive and heavy arm were improved after hand amputation. Functional outcomes were improved with this revolutionary myoelectric prosthesis technique. The patient was able to use his prosthesis for many daily activities. Selective amputation indications after traumatic brachial plexus injury are a heavy and stiff arm with shoulder subluxation pain and an unusable claw hand. The patient's motivation must be high.

Pediatric Digit Replantation Following Traumatic Amputation: Nationwide Analysis of Patient Selection, Outcomes, and Cost

Background: Indications for replantation following traumatic digit amputations are more liberal in the pediatric population than in adults, but delineation of patient selection within pediatrics and their outcomes have yet to be elucidated. This study uses a national pediatric database to evaluate patient characteristics and injury patterns involved in replantation and their outcomes. Methods: The Healthcare Cost and Utilization Project Kid's Inpatient Database was queried for traumatic amputations of the thumb and finger from 2000 to 2012. Participants were separated into those who underwent replantation and those who underwent amputation. Patients undergoing replantation were further divided into those requiring revision amputation and/or microvascular revision. Patient age, sex, insurance, digit(s) affected, charges, length of stay, and complications were extracted for each patient. Results: Traumatic digit amputations occurred in 3090 patients, with 1950 (63.1%) undergoing revision amputation and 1140 (36.9%) undergoing replantation. Younger patients, those with thumb injuries, females, and those covered under private insurance were significantly more likely to undergo replantation. Cost, length of stay, and in-hospital complications were significantly greater in replantation patients than in those who had undergone amputation. Following replantation, 237 patients (20.8%) underwent revision amputation and 209 (18.3%) underwent vascular revision, after which 58 required revision amputation. Risk of revision following replantation involved older patients, males, and procedures done recently. Conclusions: Pediatric patients who underwent replantation were significantly younger, female, had thumb injuries, and were covered by private insurance. Our findings demonstrate that in addition to injury factors, demographics play a significant role in the decision for finger replantation and its outcomes.

Dimensionality analysis of forearm muscle activation for myoelectric control in transradial amputees

Establishing a natural communication interface between the user and the terminal device is one of the central challenges of hand neuroprosthetics research. Surface electromyography (EMG) is the most common source of neural signals for interpreting a user’s intent in these interfaces. However, how the capacity of EMG generation is affected by various clinical parameters remains largely unknown. In this study, we examined the EMG activity of forearm muscles recorded from 11 transradially amputated subjects who performed a wide range of movements. EMG recordings from 40 able-bodied subjects were also analyzed to provide comparative benchmarks. By using non-negative matrix factorization, we extracted the synergistic EMG patterns for each subject to estimate the dimensionality of muscle control, under the framework of motor synergies. We found that amputees exhibited less than four synergies (with substantial variability related to the length of remaining limb and age), whereas able-bodied subjects commonly demonstrate five or more synergies. The results of this study provide novel insight into the muscle synergy framework and the design of natural myoelectric control interfaces.

A Physics-based Virtual Reality Environment to Quantify Functional Performance of Upper-limb Prostheses

Usability of upper-limb prostheses remains to be a challenge due to the complexity of hand-object interactions in activities of daily living. Functional evaluation is critical for the optimization of prosthesis performance during device design and parameter tuning phase. Therefore, we implemented a low-cost physics-based virtual reality environment (VRE) capable of simulating wide range of object grasping and manipulation tasks to enable human-in-the-loop optimization. Importantly, our novel VRE can assess user performance quantitatively using movement kinematics and interaction forces. We present a preliminary experiment to validate our VRE. Four able-bodied subjects performed object transfer tasks with a simulated myoelectric one DoF soft-synergy prosthetic hand, while wearing braces to restrain different levels of wrist motion. We found that the task completion time was similar across conditions, however limited wrist pronation led to more shoulder compensatory motion whereas challenging object orientation caused more torso compensatory motion.

Perioperative Pain Management Strategies for Amputation: A Topical Review

Objective

To review acute pain management strategies in patients undergoing amputation with consideration of preoperative patient factors, pharmacologic/interventional modalities, and multidisciplinary care models to alleviate suffering in the immediate post-amputation setting.

Background

Regardless of surgical indication, patients undergoing amputation suffer from significant residual limb pain and phantom limb pain in the acute postoperative phase. Most studies have primarily focused on strategies to prevent persistent pain with inclusion of immediate postoperative outcomes as secondary measures. Pharmacologic agents, including gabapentin, ketamine, and calcitonin, and interventional modalities such as neuraxial and perineural catheters, have been examined in the perioperative period.

Design

Focused Literature Review.

Results

Pharmacologic agents (gabapentin, ketamine, calcitonin) have not shown consistent efficacy. Neuraxial analgesia has demonstrated both an opioid sparing and analgesic benefit while results have been mixed regarding perineural catheters in the immediate post-amputation setting. However, several early studies of perineural catheters employed sub-optimal techniques (distal surgical placement), and prolonged use of perineural catheters may provide a sustained benefit. Regardless of analgesic technique, a multidisciplinary approach is necessary for optimal care.

Conclusion

Patient-tailored analgesic regimens utilizing catheter-based techniques are essential in the acute post-amputation phase and should be implemented in all patients undergoing amputation. Future research should focus on improved measurement of acute pain and comparisons of effective analgesic regimens instead of single techniques.

Flexor Digitorum Superficialis Tenodesis for Traumatic Digit Amputation at the Level of the Proximal Phalanx

BACKGROUND

Traumatic amputation of the digit requiring revision amputation at the level of the proximal phalanx provides the opportunity to improve flexor function via tenodesis of the remaining flexor digitorum superficialis (FDS) tendon. Salvage of the remaining FDS and performing flexor tenodesis to the proximal phalanx allows increased flexion at the metacarpophalangeal (MCP) joint.

METHODS

This series reviews FDS tenodesis, outlining its surgical technique with clinical and functional outcomes. Institutional review board-approved retrospective study was performed. Twelve digits in 8 patients were included.

RESULTS

Average flexion-extension arc of affected MCP joint was 82°, and average grip strength was 70% of unaffected extremity. No patients required revision surgery or revision amputation. One patient had a minor wound infection treated successfully with oral antibiotics.

CONCLUSIONS

FDS tenodesis is a reliable motion-preserving procedure for patients with amputations at the level of the proximal phalanx to maintain flexion at the MCP joint.

Bilateral hand squamous-cells carcinoma in patient affected with non-Hodgkin lymphoma. Case report and literature review

BACKGROUND

Squamous-cell skin cancer is the most frequent tumor in the hand. It occurs on sun-damaged skin, especially in lightskinned individuals with a long history of chronic sun exposure.

CASE REPORT

We describe a case of bilateral hand squamous-cell carcinoma in a elderly patient affected with non-Hodgkin's lymphoma, who underwent several non-successful surgical treatment, radiotherapy and at the least, amputation of right hand for rapid clinical evolution after radiotreatment. Available literature on the subject has been reviewed.

RESULTS

In our case, after several non-successful treatment, elective amputation at the distal third of forearm was performed. We reviewed 56 items including books, original articles, reviews, cases report.

CONCLUSIONS

Current evidence on treatment of hand squamouscells carcinoma is to perform a first radical surgical treatment in order to avoid recurrence/metastasis and to achieve a safer level of amputation thus increasing the surface area of healthy tissue available for eventually subsequent reconstruction/prosthesization.

The role of elective amputation in patients with traumatic brachial plexus injury

BACKGROUND AND AIM

Despite undergoing complex brachial plexus, surgical reconstructions, and rehabilitation, some patients request an elective amputation. This study evaluates the role of elective amputation after brachial plexus injury.

METHODS

A retrospective chart review was performed for all the 2140 patients with brachial plexus injuries treated with elective amputation between 1999 and 2012 at a single institution. Analysis was conducted on the potential predisposing factors for amputation, amputation level, and postamputation complications. Patients were evaluated using pre- and postamputation Disabilities of the Shoulder, Arm, and hand scores in addition to visual analog pain scores.

RESULTS

The following three conditions were observed in all nine patients who requested an elective amputation: (1) Pan-plexus injury; (2) non-recovery (mid-humeral amputation) or elbow flexion recovery only (forearm amputation) 1 year after all other surgical options were performed; and (3) at least one chronic complication (chronic infection, nonunion fractures, full-thickness burns, chronic neck pain with arm weight, etc.). Pain improvement was found in five patients. Subjective patient assessments and visual analog pain scores before and after amputation did not show a statistically significant improvement in Disabilities of the Shoulder, Arm, and Hand Scores. However, four patients reported that their shoulder pain felt "better" than it did before the amputation, and two patients indicated they were completely cured of chronic pain after surgery.

CONCLUSIONS

Elective amputation after brachial plexus injury should be considered as an option in the above circumstances. When the informed and educated decision is made, patients can have satisfactory outcomes regarding amputation.