Residual limb volume fluctuations in transfemoral amputees.

This study constitutes the first attempt to systematically quantify residual limb volume fluctuations in transfemoral amputees. The study was carried out on 24 amputees to investigate variations due to prosthesis doffing, physical activity, and testing time. A proper experimental set-up was designed, including a 3D optical scanner to improve precision and acceptability by amputees. The first test session aimed at measuring residual limb volume at 7 time-points, with 10 min intervals, after prosthesis doffing. This allowed for evaluating the time required for volume stabilization after prosthesis removal, for each amputee. In subsequent sessions, 16 residual limb scans in a day for each amputee were captured to evaluate volume fluctuations due to prosthesis removal and physical activity, in two times per day (morning and afternoon). These measurements were repeated in three different days, a week apart from each other, for a total of 48 scans for each amputee. Volume fluctuations over time after prosthesis doffing showed a two-term decay exponential trend (R2 = 0.97), with the highest variation in the initial 10 min and an average stabilization time of 30 min. A statistically significant increase in residual limb volume following both prosthesis removal and physical activity was verified. No differences were observed between measures collected in the morning and in the afternoon.Clinical Trials.gov ID: NCT04709367.

Regrowth of zebrafish caudal fin regeneration is determined by the amputated length.

Fish have a high ability to regenerate fins, including the caudal fin. After caudal fin amputation, original bi-lobed morphology is reconstructed during its rapid regrowth. It is still controversial whether positional memory in the blastema cells regulates reconstruction of fin morphology as in amphibian limb regeneration, in which limb blastema cells located at the same proximal-distal level have the same positional identity. We investigated growth period and growth rate in zebrafish caudal fin regeneration. We found that both the growth period and growth rate differed for fin rays that were amputated at the same proximal-distal level, indicating that it takes different periods of time for fin rays to restore their original lengths after straight amputation. We also show that more proximal amputation takes longer period to reconstruct the original morphology/size than more distal amputation. Statistical analysis suggested that both the growth period/rate are determined by amputated length (depth) regardless of the fin ray identity along dorsal-ventral axis. In addition, we suggest the possibility that the structural/physical condition such as width of the fin ray at the amputation site (niche at the stump) may determine the growth period/rate.

Does closed incision negative wound pressure therapy in non-traumatic major lower-extremity amputations improve survival rates?

Closed incision negative pressure wound therapy (CINPWT) has been shown to be clinically effective compared with the traditional gauze dressing, reducing surgical site infections and wound complications. We evaluated the effect of CINPWT compared with gauze dressing on the need for revision surgery and survival after non-traumatic major lower amputation. We included 309 patients undergoing 403 major lower amputations in a retrospective study from January 1, 2010 to November 23, 2017. A total of 139 patients received CINPWT, and 170 patients received stump bandage. There was no statistically significant difference between the two groups regarding the need for revision surgery (P = .45). Fourteen stump bandage patients and 15 CINPWT patients died in hospital (P = .57). One year after amputation, 55 CINPWT patients and 66 stump bandage patients had died (P = .82). Survival probabilities adjusted for age and gender 2 years after amputation were .52 (.43-.61) and .49 (.42-.58), respectively, and 3 years after amputation were .36 (.25-.50) and .39 (.32-.47), respectively. We also found no significant difference in the need for revision surgery in survival probabilities up till 3 years after amputation between patients treated with CINPWT and patients treated with gauze bandage postoperatively.

Unilateral granuloma annulare in association with pyoderma gangrenosum and chronic lymphocytic leukemia.

Granuloma annulare (GA) is a fairly common inflammatory skin condition with a range of clinical subtypes. We describe an unusual case of unilateral GA confined to the thigh on a previously amputated limb. A man in his 80s with a past medical history of below-knee amputation of the left leg owing to severe leg ulcers from pyoderma gangrenosum, chronic lymphocytic leukemia, and dyslipidemia developed a slowly spreading eruption on the distal stump spreading proximally. On physical examination, he had numerous non-scaly violaceous papules and annular plaques from the stump to the lateral, medial, and anterior thigh. Histology confirmed a diagnosis of GA. The extensive, chronic lesions make this presentation of GA very unusual in that it shares features of both localized and generalized forms. Moreover, the temporal and spatial association with pyoderma gangrenosum is unique and may reflect a related inflammatory pathway.

Osteomyelitis in limb amputated by amniotic band sequence.

A preterm (30+2 week) neonate with below-knee amputation (right lower limb), constriction rings and syndactyly, subsequent to amniotic band sequence, developed pus discharge from the right tibial stump. The neonate did not have clinical features of systemic sepsis. Blood culture was sterile. The pus culture, however, grew methicillin-resistant coagulase-negative Staphylococcus and bone scan was suggestive of osteomyelitis of right proximal tibial stump. Osteomyelitis was likely caused by the contiguous spread of infection from the exposed stump. Neonate was treated with intravenous antibiotics for 4 weeks and discharged on oral feeds.

Is skin pressure a relevant factor for socket assessment in patients with lower limb amputation?

BACKGROUND: Prosthetic rehabilitation improves the overall quality of life of patients, despite discomfort and medical complications. No quantitative assessment of prosthesis-patient interaction is used in routine protocols and prosthesis quality still results from the manufacturer's know-how. OBJECTIVE: Our objective is to investigate whether pressure can be a relevant factor for assessing socket adequacy. METHODS: A total of 8 transtibial amputee volunteers took part in this experimental study. The protocol included static standing and 2 minutes walking tests while the stump-to-socket interface pressures were measured. Questionnaires on comfort and pain were also conducted. RESULTS: During static standing test, maximum pressures were recorded in the proximal region of the leg, with a peak value reaching 121.1 ± 31.6 kPa. During dynamic tests, maximum pressures of 254.1 ± 61.2 kPa were recorded during the loading phase of the step. A significant correlation was found between the pain score and static maximum recorded pressure (r= 0.81). CONCLUSIONS: The protocol proposed and evaluated in this study is a repeatable, easy-to-set quantified analysis of the patient to socket interaction while standing and walking. This approach is likely to improve feedback for prosthesis manufacturers and consequently the overall design of prostheses.

Risk factors for reoperation, readmission, and early complications after below knee amputation.

BACKGROUND: Many patients undergoing below knee amputations (BKA) return for subsequent unplanned operations, hospital readmission, or postoperative complications. This unplanned medical management negatively impacts both patient outcomes and our healthcare system. This study primarily investigates the risk factors for unplanned reoperation following BKA. METHODS: Below knee amputations from the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database from the years 2012-2014 were identified by CPT code 27880 for amputation through the tibia and fibula. Our query identified 4631 BKA cases, including 30 day complications. Multivariate logistic regression modeling was performed on several patient demographic and disease factors to assess for independent predictors of unplanned reoperation. Secondary outcomes of unplanned and related readmissions (related to the procedure), major complications, minor complications, and mortality were also included in the analysis. RESULTS: Of 4631 BKAs identified, 9.63% (446/4631) underwent unplanned reoperations and 8.75% (405/4631) had unplanned and related readmissions. Major complications were experienced by 12.8% (593/4631) and minor complications by 8.7% (401/4631). Thirty day mortality rate was 5.14% (238/4631). The most common procedures for unplanned operations were thigh amputations (128/446, 28.7%), debridement/secondary closure (114/446, 25.6%), and revision leg amputations (46/446, 10.32%). Factors associated with an increased risk of unplanned reoperation included patients transferred from another facility (Adjusted Odds Ratio [AOR] = 1.28; p = .04), recent smokers (AOR = 1.34; p = .02), bleeding disorder (AOR = 1.30; p = .02), and preoperative ventilator use (AOR = 2.38; p = .01). CONCLUSION: Patients that were ongoing/recent smokers, had diagnosed bleeding disorders, required preoperative ventilator use, or were transferred in from another facility were associated with the highest risks of reoperation following BKA. This patient population experiences high rates of reoperation, readmission, complication, and mortality.

Time course of traumatic neuroma development.

This study was designed to characterize morphologic stages during neuroma development post amputation with an eye toward developing better treatment strategies that intervene before neuromas are fully formed. Right forelimbs of 30 Sprague Dawley rats were amputated and limb stumps were collected at 3, 7, 28, 60 and 90 Days Post Amputation (DPA). Morphology of newly formed nerves and neuromas were assessed via general histology and neurofilament protein antibody staining. Analysis revealed six morphological characteristics during nerve and neuroma development; 1) normal nerve, 2) degenerating axons, 3) axonal sprouts, 4) unorganized bundles of axons, 5) unorganized axon growth into muscles, and 6) unorganized axon growth into fibrotic tissue (neuroma). At early stages (3 & 7 DPA) after amputation, normal nerves could be identified throughout the limb stump and small areas of axonal sprouts were present near the site of injury. Signs of degenerating axons were evident from 7 to 90 DPA. From day 28 on, variability of nerve characteristics with signs of unorganized axon growth into muscle and fibrotic tissue and neuroma formation became visible in multiple areas of stump tissue. These pathological features became more evident on days 60 and 90. At 90 DPA frank neuroma formation was present in all stump tissue. By following nerve regrowth and neuroma formation after amputation we were able to identify 6 separate histological stages of nerve regrowth and neuroma development. Axonal regrowth was observed as early as 3 DPA and signs of unorganized axonal growth and neuroma formation were evident by 28 DPA. Based on these observations we speculate that neuroma treatment and or prevention strategies might be more successful if targeted at the initial stages of development and not after 28 DPA.

Change in residual limb size over time in the NU-FlexSIV socket: A case study.

BACKGROUND:: This case study represented a unique opportunity wherein a long-time user of sub-ischial sockets had kept nearly every socket he wore for a decade. This individual let us borrow these sockets so we could digitize them and indirectly assess change in residual limb size over time by calculating changes in socket volume and circumferences over time. CASE DESCRIPTION AND METHODS:: Over a decade, the subject maintained a relatively stable body weight of 84-88 kg and received nine sub-ischial sockets. The internal surface of each socket was scanned using a mechanical digitizer and volume and circumferences calculated. FINDINGS AND OUTCOMES:: Socket volume increased 31.3%, from a low of 2659.2 cm3 for the oldest socket to a high of 3490.6 cm3 for the most recent socket. Proximal circumferences increased more than distal circumferences with a 15.9% total increase proximally versus 8.9% total increase distally. DISCUSSION AND CONCLUSION:: The results suggest that this individual's residual limb increased in size over time despite the compressive effect of the socket and liner. In addition, the increase in circumference was greater proximally than distally, which is where the remaining muscle bellies are located. CLINICAL RELEVANCE: This case study provides insight into the long-term effect of the sub-ischial socket on residual limb volume given compression of the soft tissues by the socket system.

Incidence and associations of painful neuroma in a contemporary cohort of lower-limb amputees.

BACKGROUND: The painful post amputation neuroma significantly impairs the prosthesis-wearing lower-limb amputee. It remains poorly understood, with literature limited to cohorts of traumatic amputees. This paper reports the incidence and associations of painful neuroma in a modern tertiary centre with a case load of amputations performed for both traumatic and non-traumatic indications. METHOD: This retrospective cohort study analysed the records of 304 patients who underwent all-cause lower-limb amputation at The Alfred Hospital between January 2002 and March 2012. Patients were included in our analysis if they completed 1-year follow-up at our Amputee Rehabilitation Clinic, producing a final cohort of 96 patients. In order to identify a painful neuroma post-operatively, both clinical suspicion, and either histopathological or radiological evidence were required. RESULTS: The overall incidence of symptomatic neuromas was 4.17%. There was no significant difference between patients who underwent amputation for a traumatic indication (6.25% (2/32) versus 3.13% (2/64); P = 0.59) compared to non-traumatic indication (P = 0.59). Visual analogue score at discharge and the presence of phantom limb pain at follow-up showed significant associations with the formation of painful neuroma. Dose of opioid on discharge, history of depression and current smoking did not reach statistical significance. CONCLUSION: This study presents a lower incidence of painful post-amputation neuroma to those published in the literature. This may be attributed to improved methodology. The described associations require further investigation into central factors leading to neuroma sensitization.

Successful forearm prosthesis fitting in a patient with epidermolysis bullosa dystrophica: Case report.

BACKGROUND: Epidermolysis bullosa dystrophica is a rare dermatological disease characterized by extreme skin fragility and elevated risk of developing a squamous cell carcinoma. In some cases, amputation of a limb is necessary. Case description and methods: A 37-year-old man with recessive, severe generalized epidermolysis bullosa dystrophica developed a squamous cell carcinoma on the right forearm requiring a below-elbow amputation. Preoperative advice concerning indication and level of amputation was given. Due to potential skin problems, a conventional prosthesis was not feasible. Findings and outcomes: A custom-designed adaptive prosthesis with an upper arm cuff was trialed and was well tolerated. Multiple working tools, attached with a rotation and inclination system, allowed independence and return to work. CONCLUSION: Despite multiple potential skin problems of the stump, the patient was successfully fitted with a custom-designed adaptive prosthesis. Preparation for this fitting was done by a comprehensive multidisciplinary patient-centered approach. Clinical relevance Despite severe skin fragility, a patient with epidermolysis bullosa dystrophica was successfully fitted with a custom-designed adaptive upper limb prosthesis allowing good functional outcome. This required a multidisciplinary and patient-centered approach.

Intra-arterial fibrinolysis for the management of acute ischemia on a below-knee amputation stump. Case report.

Preservation of the knee joint has enormous advantages in terms of mobility and rehabilitation of an amputee. Any cause of breakdown requiring revision to an above-knee amputation is a major setback because it reduces the patient's rehabilitative potential. We report a case of intra-arterial thrombolysis use to save a below-knee amputation stump with acute ischemia. A 56-year-old man who sought the emergency department with 1-day history of acute pain on his right below-knee stump. The angiography confirmed popliteal artery occlusion. Pharmacomechanical thrombectomy, with Aspirex (rotational catheter to restore blood flow in occluded vessel, by removing occlusion material from the vessel) and recombinant tissue plasminogen activator, was performed. After 9 years of follow-up the patient remained asymptomatic, capable of independent ambulation with prosthetic limb. Intra-arterial fibrinolysis seems to be a safe and effective treatment for cases of acutely ischemic amputation stump.

Intense Focused Ultrasound Preferentially Stimulates Transected Nerves Within Residual Limbs: Pilot Study.

Objective: Identifying pain generators in tissue deep in the skin can require uncomfortable, complicated, and invasive tests. We describe pilot studies testing the hypothesis that ultrasound image-guided, intense focused ultrasound (ig-iFU) can noninvasively and differentially stimulate the end of transected nerves in the residual limbs of amputee patients. Design: We applied iFU to the transected nerve ending as individual pulses with a length of 0.1 seconds using a carrier frequency of 2.0 MHz. After targeting, we gradually increased the iFU intensity to reach consistent patient-reported stimulation of the transected nerve ending. We also stimulated the proximal nerve, tissue near the nerve ending, and the intact contralateral nerve. We described the resulting sensations and correlated the results of the study participant's pre-iFU study responses to phantom and residual limb pain questionnaires. Results: iFU spatial and temporal average intensity values between 16 W/cm2 and 433 W/cm2 that were applied to the transected nerve ending and proximal nerve elicited sensations, including phantom limb sensations, while the same intensity applied to control tissue centimeters away from the nerve ending, or to the intact nerve on the contralateral limb, did not. Two out of 11 study participants reported only mild and transient pain created by iFU stimulation. Successful iFU intensity values correlated with neither phantom nor residual limb pain scores. Conclusions: Transected nerves had greater sensitivity to iFU stimulation than ipsilateral and contralateral control tissue, including intact nerve. These results support the view that ig-iFU may one day help physicians identify deep, tender tissue in patients who report experiencing pain.

Intra-arterial fibrinolysis for the management of acute ischemia on a below-knee amputation stump. Case report / Fibrinólise intra-arterial para tratamento da isquemia aguda em coto de amputação infrapatelar. Relato de caso

ABSTRACT Preservation of the knee joint has enormous advantages in terms of mobility and rehabilitation of an amputee. Any cause of breakdown requiring revision to an above-knee amputation is a major setback because it reduces the patient's rehabilitative potential. We report a case of intra-arterial thrombolysis use to save a below-knee amputation stump with acute ischemia. A 56-year-old man who sought the emergency department with 1-day history of acute pain on his right below-knee stump. The angiography confirmed popliteal artery occlusion. Pharmacomechanical thrombectomy, with Aspirex (rotational catheter to restore blood flow in occluded vessel, by removing occlusion material from the vessel) and recombinant tissue plasminogen activator, was performed. After 9 years of follow-up the patient remained asymptomatic, capable of independent ambulation with prosthetic limb. Intra-arterial fibrinolysis seems to be a safe and effective treatment for cases of acutely ischemic amputation stump.

RESUMO A preservação da articulação do joelho tem grandes vantagens para a mobilidade e a reabilitação de um amputado. Qualquer causa que exija revisão para uma amputação acima do joelho é um grande revés, porque reduz o potencial de reabilitação do paciente. O objetivo aqui foi descrever o uso de trombólise intra-arterial para salvar um coto de amputação abaixo do joelho com isquemia aguda. Homem, 56 anos, procurou pronto atendimento de nosso hospital com histórico de 1 dia de dor aguda em seu coto de amputação infrapatelar direito. A angiografia confirmou oclusão da artéria poplítea. Foi realizada trombectomia farmacomecânica com Aspirex (cateter rotativo para restabelecer o fluxo sanguíneo em vasos ocluídos, removendo material de oclusão do vaso) e ativador do plaminogênio tecidual recombinante. Após 9 anos de seguimento, o paciente permanecia assintomático, capaz de deambulação independente com membro protético. A fibrinólise intra-arterial parece ser um tratamento seguro e eficaz para casos selecionados de coto de amputação com isquêmica aguda.

Free-Flap Transfer for Coverage of Transmetatarsal Amputation Stump to Preserve Residual Foot Length.

Surgical management of soft-tissue defects of the forefoot and midfoot caused by trauma or diabetic complications can be challenging because locoregional tissue is insufficient to provide adequate flap. This deficiency necessitates higher-level amputations, such as Chopart or even transtibial amputation, resulting in far more debilitating functional outcomes than are seen with partial foot amputation. The purpose of this study was to examine the surgical outcomes after transmetatarsal amputation and a free-flap transfer to preserve foot length. This prospective case series was conducted from January 2011 to December 2015 at the Department of Plastic and Reconstructive Surgery at our institute. A total of 16 patients (11 men and 5 women) were enrolled in this study, all of whom were candidates for higher-level amputation because of inadequate soft-tissue coverage after debridement. Each patient underwent transmetatarsal amputation and reconstruction of the amputation stump using free-flap transfers to preserve foot length. Preoperative and postoperative data were collected to evaluate the postoperative outcomes. All 16 free-flap transfers were successful, with no major complications. In 2 cases, partial flap necrosis required additional skin grafting. The mean follow-up period was 24.3 months (range = 7-55 months). Flap coverage was stable, and all the patients were comfortable with their prostheses at long-term follow-up. Use of a free flap to reconstruct a transmetatarsal amputation stump provided stable coverage, preserved maximal foot length, and resulted in good functional outcomes.

Effect of C1-INH on ischemia/reperfusion injury in a porcine limb ex vivo perfusion model.

Revascularization of an amputated limb within 4-6h is essential to avoid extensive ischemia/reperfusion (I/R) injury leading to vascular leakage, edema and tissue necrosis. I/R injury is a pathological inflammatory condition that occurs during reperfusion of an organ or tissue after prolonged ischemia. It is characterized by a complex crosstalk between endothelial cell activation and the activation of plasma cascades. Vasculoprotective pharmacological intervention to prevent I/R injury might be an option to prolong the time window between limb amputation and successful replantation. We used C1-easterase inhibitor (C1-INH) in this study because of its known inhibitory effects on the activation of the complement, coagulation and kinin cascades. Forelimbs of 8 large white pigs were amputated, subjected to ischemia, and then reperfused with autologous whole blood. All limbs were exposed to 9h of cold ischemia at 4°C. After 2h of cold ischemia the limbs were either perfused with of C1-INH (1U/ml in hydroxyethyl starch, n=8) or hydroxyethyl starch alone (n=7). After completion of the 9-h ischemia period, all limbs were ex vivo perfused with heparinized autologous whole blood for 12h using a pediatric heart lung machine to simulate in vivo revascularization. Our results show that I/R injury in the control group led to a significant elevation of tissue deposition of IgG and IgM, complement C3b/c, C5b-9 and MBL. Also, activation of the kinin system was significantly increased, namely bradykinin in plasma, and expression of bradykinin receptors 1 and 2 in tissue. In addition, markers for endothelial integrity like expression of CD31, VE-cadherin and heparan sulfate proteoglycans were decreased in reperfused tissue. Limb I/R injury also led to activation of the coagulation cascade with a significant elevation of fibrin and thrombin deposition and increased fibrinogen-like protein-2 expression. C1-INH treated limbs showed much less activation of plasma cascades and better protection of endothelial integrity compared to the reperfused control limbs. In conclusion, the use of the cytoprotective drug C1-INH significantly reduced I/R injury by protecting the vascular endothelium as well as the muscle tissue from deposition of immunoglobulins, complement and fibrin.