-
Sensors (Basel, Switzerland) Jul 2023The soft tissues of residual limb amputees are subject to large volume fluctuations over the course of a day. Volume fluctuations in residual limbs can lead to local...
The soft tissues of residual limb amputees are subject to large volume fluctuations over the course of a day. Volume fluctuations in residual limbs can lead to local pressure marks, causing discomfort, pain and rejection of prostheses. Existing methods for measuring interface stress encounter several limitations. A major problem is that the measurement instrumentation is applied in the sensitive interface between the prosthesis and residual limb. This paper presents the principle investigation of a non-intrusive technique to evaluate the fit of orthopaedic prosthesis sockets in transfemoral amputees based on experimentally obtained vibrational data. The proposed approach is based on changes in the dynamical behaviour detectable at the outer surface of prostheses; thus, the described interface is not affected. Based on the experimental investigations shown and the derived results, it can be concluded that structural dynamic measurements are a promising non-intrusive technique to evaluate the fit of orthopaedic prosthesis sockets in transfemoral amputee patients. The obtained resonance frequency changes of 2% are a good indicator of successful applicabilityas these changes can be detected without the need for complex measurement devices.
Topics: Humans; Prosthesis Design; Orthopedics; Prosthesis Implantation; Artificial Limbs; Amputees; Amputation Stumps
PubMed: 37514793
DOI: 10.3390/s23146500 -
Cell Regeneration (London, England) Jul 2023Deer antlers are the only known mammalian organ that, once lost, can fully grow back naturally. Hence, the antler offers a unique opportunity to learn how nature has... (Review)
Review
Deer antlers are the only known mammalian organ that, once lost, can fully grow back naturally. Hence, the antler offers a unique opportunity to learn how nature has solved the problem of mammalian epimorphic regeneration (EpR). Comprehensive comparisons amongst different types of EpR reveal that antler renewal is fundamentally different from that in lower vertebrates such as regeneration of the newt limb. Surprisingly, antler renewal is comparable to wound healing over a stump of regeneration-incompetent digit/limb, bone fracture repair, and to a lesser extent to digit tip regeneration in mammals. Common to all these mammalian cases of reaction to the amputation/mechanical trauma is the response of the periosteal cells at the distal end/injury site with formation of a circumferential cartilaginous callus (CCC). Interestingly, whether the CCC can proceed to the next stage to transform to a blastema fully depends on the presence of an interactive partner. The actual form of the partner can vary in different cases with the nail organ in digit tip EpR, the opposing callus in bone fracture repair, and the closely associated enveloping skin in antler regeneration. Due to absence of such an interactive partner, the CCC of a mouse/rat digit/limb stump becomes involuted gradually. Based on these discoveries, we created an interactive partner for the rat digit/limb stump through surgically removal of the interposing layers of loose connective tissue and muscle between the resultant CCC and the enveloping skin after amputation and by forcefully bonding two tissue types tightly together. In so doing partial regeneration of the limb stump occurred. In summary, if EpR in humans is to be realized, then I envisage that it would be more likely in a manner akin to antler regeneration rather to that of lower vertebrates such as newt limbs.
PubMed: 37490254
DOI: 10.1186/s13619-023-00169-4 -
BMC Sports Science, Medicine &... Jul 2023The main aim of this paper is to present the feasibility of rigorously designed multiple N-of-1 design in prosthetics research. While research of adequate power and high...
BACKGROUND
The main aim of this paper is to present the feasibility of rigorously designed multiple N-of-1 design in prosthetics research. While research of adequate power and high quality is often lacking in rehabilitation, N-of-1 trials can offer a feasible alternative to randomized controlled group trials, both increasing design power at group level and allowing a rigorous, statistically confirmed evaluation of effectiveness at a single patient level. The paper presents a multiple N-of-1 trial protocol, which aim is to evaluate the effectiveness of Unity, a prosthetic add-on suspension system for amputees, on patient-reported comfort during daily activities (main outcome measure), prosthesis wearing time, perception of limb-prosthesis fitting and stump volume and functional walking parameters.
METHODS
Multicenter, randomized, prospective, double-blind multiple N-of-1 trial using an introduction/withdrawal design alternating Unity connected/disconnected phases of randomized length on twenty patients with unilateral transtibial amputation. The primary outcome measure is the Prosthetic Socket Comfort Score (SCS), a validated measure of comfort, administered daily by an phone app designed for the study. Secondary outcomes measures will be collected during the 50 days period of the N-of-1 trial: (1) by the same app, daily for patient-reported limb-prosthesis fitting, stump volume variation, and daily wearing time of the prosthesis; (2) by a pedometer for the number of steps per day; (3) by blind assessors in the rehabilitation center during adjustment visits for functional walking parameter (L-Test, 6-minute walk test), and by the patient for the QUEST, and ABC-S. Effectiveness of the Unity system regarding SCS and daily secondary outcome measures will be tested by randomization test. The secondary outcome measures assessed during visits in the rehabilitation center will be analyzed by Non Overlap of All pairs. An estimate of the effect on the amputee population will be generated by aggregating each individual clinical trial (N-of-1 trial) by Hierarchical Bayesian methods.
DISCUSSION
This study protocol was designed to answer the question "which device is best for THIS patient" and to conclude at a group level on the effectiveness of a new devic, using a Multiple N-of-1 trial, which is promising but underused in prosthetics research so far.
TRIAL REGISTRATION
N° ID-RCB 2020-A01309-30 Clintrial.gov : NCT04804150 - Retrospectively registered March 20th 2021.
PubMed: 37452356
DOI: 10.1186/s13102-023-00694-4 -
Annals of the Royal College of Surgeons... May 2024The aim was to study the effect of incisional negative pressure wound therapy (iNPWT) in wound healing compared with standard sterile gauze dressings after major lower... (Randomized Controlled Trial)
Randomized Controlled Trial
INTRODUCTION
The aim was to study the effect of incisional negative pressure wound therapy (iNPWT) in wound healing compared with standard sterile gauze dressings after major lower extremity amputation in patients with peripheral arterial disease (PAD).
METHODS
This prospective, randomised controlled trial included 50 patients undergoing major lower extremity amputations for PAD. Patients were randomised into iNPWT and standard dressing groups. The patency of blood vessels at the level of the stump was ensured with or without revascularisation. The primary outcome was wound-related complications such as surgical site infection (SSI), wound dehiscence, seroma/haematoma formation or the need for revision amputation. The secondary outcome was the time taken for the eligibility of prosthesis placement.
RESULTS
It was found that only 12% of the patients in the iNPWT group had SSI compared with 36% in the standard dressing group ( = 0.047). Rates of wound dehiscence, seroma/haematoma formation and revision amputation were decreased in the iNPWT group but this was not statistically significant ( > 0.05). There was a significant reduction in the time taken for eligibility of prosthesis placement in the iNPWT group (5.12 ± 1.53 vs 6.8 ± 1.95 weeks, = 0.002).
CONCLUSIONS
iNPWT is effective in reducing the incidence of SSI and the time taken for rehabilitation in patients undergoing major lower limb amputation due to PAD.
Topics: Humans; Negative-Pressure Wound Therapy; Male; Female; Amputation, Surgical; Middle Aged; Prospective Studies; Aged; Lower Extremity; Wound Healing; Peripheral Arterial Disease; Surgical Wound Infection; Treatment Outcome; Bandages
PubMed: 37435705
DOI: 10.1308/rcsann.2023.0011 -
Medicinski Glasnik : Official... Aug 2023Aim To investigate the effect of direct epineural electrical stimulation of the nerve on the nature of reparative processes in the bone stump. Methods Three series of...
Aim To investigate the effect of direct epineural electrical stimulation of the nerve on the nature of reparative processes in the bone stump. Methods Three series of experiments were carried out with amputation of the thigh in the middle third and muscle plasty. In the 1st and 2nd experimental series a perineural catheter was brought to the stump of the sciatic nerve, through which mechanical irritation of the nerve was performed for 20 days daily for 20 minutes. In the 2nd series, an electrode was added to the nerve and epineural electrical stimulation was performed daily for 20 days. Animals of the 3rd series served as control. The observation periods were 1, 3, 6 months. Histological research method with filling vessels with ink-gelatin mixture was applied. Results In the 1st series, there was a sharp distortion of the reparative process, which consisted of a violation of microcirculation, changes in shape, resorption of the cortical diaphyseal plate, fractures, deformations. In most experiments of the 2nd series, organotypic stumps were formed with normalization of microcirculation. In the 3rd series, results of the formation of the stump were better than in the 1st, but worse than in the 2nd series. Conclusions Painful nerve irritation after amputation leads to a significant disturbance of microcirculation and reparative regeneration at the end of the bone stump with the development of pathological restructuring of bone tissue. Electrostimulation of the nerve improves microcirculation and reparative regeneration of the bone tissue.
PubMed: 37421178
DOI: 10.17392/1602-23 -
Prosthetics and Orthotics International Apr 2024Among the different factors affecting socket comfort, the pressure applied on residual limb tissues is a crucial parameter for the success or failure of any prosthetic...
BACKGROUND
Among the different factors affecting socket comfort, the pressure applied on residual limb tissues is a crucial parameter for the success or failure of any prosthetic device. However, only a few incomplete data are available on people with transfemoral amputation, in this regard. This work aims at filling this gap in the literature.
METHODS
Ten people with transfemoral amputation wearing 3 different socket designs were recruited in this study: 2 ischial containment sockets featured by proximal trim lines that contain the ischial tuberosity and ramus and greater trochanter, 2 subischial sockets with proximal trim lines under the ischium level, and 6 quadrilateral sockets with proximal trim lines that contain the greater trochanter and create a horizontal seat for the ischial tuberosity. The pressure values at the anterior, lateral, posterior, and medial areas of the socket interface were recorded during 5 locomotion tasks (ie, horizontal, ascent, and descent walking, upstairs and downstairs) by using an F-Socket System (Tekscan Inc., Boston, MA). Gait segmentation was performed by exploiting plantar pressure, which was acquired by an additional sensor under the foot. Mean and standard deviation of minimum and maximum values were calculated for each interface area, locomotion task, and socket design. The mean pressure patterns during different locomotion tasks were reported, as well.
RESULTS
Considering all subjects irrespective of socket design, the mean pressure range resulted 45.3 (posterior)-106.7 (posterior) kPa in horizontal walking; 48.3 (posterior)-113.8 (posterior) kPa in ascent walking; 50.8 (posterior)-105.7 (posterior) kPa in descent walking; 47.9 (posterior)-102.9 (lateral) kPa during upstairs; and 41.8 (posterior)-84.5 (anterior) kPa during downstairs. Qualitative differences in socket designs have been found.
CONCLUSIONS
These data allow for a comprehensive analysis of pressures acting at the tissue-socket interface in people with transfemoral amputation, thus offering essential information for the design of novel solutions or to improve existing ones, in this field.
Topics: Humans; Amputation Stumps; Prosthesis Design; Artificial Limbs; Amputation, Surgical; Femur
PubMed: 37379468
DOI: 10.1097/PXR.0000000000000251 -
The American Surgeon Oct 2023The optimal management of major stump complications (operative infection or dehiscence) following below-knee-amputation (BKA) is unknown. We evaluated a novel operative...
INTRODUCTION
The optimal management of major stump complications (operative infection or dehiscence) following below-knee-amputation (BKA) is unknown. We evaluated a novel operative strategy to aggressively treat major stump complications hypothesizing it would improve our rate of BKA salvage.
METHODS
Retrospective review of patients requiring operative intervention for BKA stump complications between 2015 and 2021. A novel strategy employing staged operative debridement for source control, negative pressure wound therapy, and reformalization was compared to standard care (less structured operative source control or above knee amputation).
RESULTS
32 patients were studied, 29 of which were male (90.6%) with an average age of 56.1 ± 9.6 y. 30 (93.8%) had diabetes and 11 (34.4%) peripheral arterial disease (PAD). The novel strategy was used in 13 patients and 19 had standard care. Novel strategy patients had higher BKA salvage rates, 100% vs 73.7% ( = .064), and postoperative ambulatory status, 84.6% vs 57.9% ( = .141). Importantly, none of the patients undergoing the novel therapy had PAD, while all progressing to above-knee amputation (AKA) did. To better assess the efficacy of the novel technique, patients progressing to AKA were excluded. Patients undergoing novel therapy who had their BKA level salvaged (n = 13) were compared to usual care (n = 14). The novel therapy's time to prosthetic referral was 72.8 ± 53.7 days vs 247 ± 121.6 days ( < .001), but they did undergo more operations (4.3 ± 2.0 vs 1.9 ± 1.1, < .001).
CONCLUSION
Utilization of a novel operative strategy for BKA stump complications is effective in salvaging BKAs, particularly for patients without PAD.
Topics: Humans; Male; Middle Aged; Aged; Female; Treatment Outcome; Amputation, Surgical; Retrospective Studies; Peripheral Arterial Disease; Wound Healing
PubMed: 37195758
DOI: 10.1177/00031348231175504 -
Journal of Reconstructive Microsurgery Sep 2023Reconstruction of the mutilated hand is one of the most difficult challenges for hand microsurgeons. When multiple digits are amputated, orthotopic digital... (Review)
Review
BACKGROUND
Reconstruction of the mutilated hand is one of the most difficult challenges for hand microsurgeons. When multiple digits are amputated, orthotopic digital replantation of the available remnants may not adequately restore the hand function. In such cases, heterotopic digital replantation may provide a more functional reconstruction.
METHODS
Between 1997 and 2018, 53 patients with mutilating hand injuries were treated with heterotopic digital replantation at our institution. A retrospective chart review was conducted to determine the details of the injury, indications for heterotopic digital replantation, and functional outcomes.
RESULTS
In total, 173 digits were amputated from 53 patients (one patient suffered from bilateral hand injuries, so totally 54 hands). Sixty-eight digits underwent heterotopic digital replantation, 30 digits had orthotopic digital replantation, and 75 stumps were terminalized. The survival rate of digits treated by heterotopic digital replantation and orthotopic digital replantation was 83.8% (57/68) and 86.7% (26/30), respectively ( = 1). Tripod grip was achieved in 83.3% (45/54) of patients following replantation and optional secondary reconstructive surgeries.
CONCLUSION
Heterotopic digital replantation is a practical and reliable method for achieving optimal hand function following mutilating hand injuries. The basic principles are to restore a functional thumb in the first instance, followed by at least two adjacent fingers against which the thumb can oppose. This method is particularly indicated when orthotopic digital replantation of the available amputated parts would yield a suboptimal result.
Topics: Humans; Finger Injuries; Amputation, Traumatic; Retrospective Studies; Fingers; Hand Injuries; Replantation
PubMed: 36720252
DOI: 10.1055/s-0043-1761288