Patient-Reported Outcome Measures for Toe-to-Hand Transfer: A Prospective Longitudinal Study.

BACKGROUND: Patient-reported outcome measures are an important metric in evaluating treatment efficacy of reconstructive surgery. Toe-to-hand transfer can restore vital prehensile function; however, this surgery is complex, extensive rehabilitation is required, and there are concerns about donor-site morbidity. This study longitudinally explores the benefits of this procedure, from the patient's perspective, using patient-reported outcome measures. METHODS: Twenty-three patients who underwent free toe-to-hand transfers from 2012 to 2015 were evaluated preoperatively and postoperatively using the following validated questionnaires: the Michigan Hand Outcomes Questionnaire, the 36-Item Short-Form Health Survey, and the Lower Limb Outcomes Questionnaire. Subgroup analysis was performed between dominant and nondominant reconstructed hands. RESULTS: Mechanism of injury was crush in 83 percent; the remainder sustained cutting, avulsion, and burn injuries. Thirty-four toes were transferred: nine great toes, 20 second toes, and five third toes. Michigan Hand Outcomes Questionnaire results showed significant improvement in overall activities of daily living, work, aesthetics, and patient satisfaction (p < 0.05). The results of the 36-Item Short-Form Health Survey showed significant improvements in physical and emotional roles (p < 0.05). The Lower Limb Outcomes Questionnaire showed no deterioration of foot function (p = 0.55). Subgroup analysis showed significant improvement in patient-reported outcome measures for patients undergoing dominant hand reconstruction but no difference between thumb reconstruction and finger-only reconstruction. CONCLUSIONS: Patient-reported outcome measures demonstrate the significant utility of toe-to-hand transfer procedures in both functional and psychosocial domains in that there are relatively greater benefits in reconstructing the dominant hand, and that donor-site morbidity is well tolerated. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Graft-implanted, enzyme responsive, tacrolimus-eluting hydrogel enables long-term survival of orthotopic porcine limb vascularized composite allografts: A proof of concept study.

BACKGROUND: Currently, patients receiving vascularized composite allotransplantation (VCA) grafts must take long-term systemic immunosuppressive therapy to prevent immunologic rejection. The morbidity and mortality associated with these medications is the single greatest barrier to more patients being able to receive these life-enhancing transplants. In contrast to solid organs, VCA, exemplified by hand or face transplants, allow visual diagnosis of clinical acute rejection (AR), directed biopsy and targeted graft therapies. Local immunosuppression in VCA could reduce systemic drug exposure and limit adverse effects. This proof of concept study evaluated, in a large animal forelimb VCA model, the efficacy and tolerability of a novel graft-implanted enzyme-responsive, tacrolimus (TAC)-eluting hydrogel platform, in achieving long-term graft survival. METHODS: Orthotopic forelimb VCA were performed in single haplotype mismatched mini-swine. Controls (n = 2) received no treatment. Two groups received TAC hydrogel: high dose (n = 4, 91 mg TAC) and low dose (n = 4, 49 mg TAC). The goal was to find a dose that was tolerable and resulted in long-term graft survival. Limbs were evaluated for clinical and histopathological signs of AR. TAC levels were measured in serial blood and skin tissue samples. Tolerability of the dose was evaluated by monitoring animal feeding behavior and weight. RESULTS: Control limbs underwent Banff Grade IV AR by post-operative day six. Low dose TAC hydrogel treatment resulted in long-term graft survival time to onset of Grade IV AR ranging from 56 days to 93 days. High dose TAC hydrogel also resulted in long-term graft survival (24 to 42 days), but was not well tolerated. CONCLUSION: Graft-implanted TAC-loaded hydrogel delays the onset of Grade IV AR of mismatched porcine forelimb VCA grafts, resulting in long term graft survival and demonstrates dose-dependent tolerability.

Composite Graft Pretreatment With Hydrogen Sulfide Delays the Onset of Acute Rejection.

INTRODUCTION: Vascularized composite allotransplantation can reconstruct devastating tissue loss by replacing like-with-like tissues, most commonly in the form of hand or face transplantation. Unresolved technical and ethical challenges have meant that such transplants remain experimental treatments. The most significant barrier to expansion of this field is the requirement for systemic immunosuppression, its toxicity and effect on longevity.Hydrogen sulfide (H2S) has been shown experimentally to ameliorate the ischemia reperfusion injury associated with composite tissue autotransplantation, which has been linked to acute rejection in solid organ transplantation. In this protocol, a large-animal model was used to evaluate the effect of H2S on acute rejection after composite tissue allotransplantation. MATERIALS AND METHODS: A musculocutaneous flap model in SLA-mismatched swine was used to evaluate acute rejection of allotransplants in 2 groups: control animals (n = 8) and a treatment group in which the allografts were pretreated with hydrogen sulfide (n = 8). Neither group was treated with systemic immunosuppression. Acute rejection was graded clinically and histopathologically by an independent, blinded pathologist. Data were analyzed by t tests with correction for multiple comparisons by the Holm-Sídák method. RESULTS: Clinically, H2S-treated tissue composites showed a delay in the onset of rejection that was statistically significant from postoperative day 6. Histopathologically, this difference between groups was also apparent, although evidence of a difference in groups disappeared beyond day 10. CONCLUSIONS: Targeted hydrogen sulfide treatment of vascularized composite allografts immediately before transplantation can delay acute rejection. This may, in turn, reduce or obviate the requirement for systemic immunosuppression.

C1 esterase inhibitor ameliorates ischemia reperfusion injury in a swine musculocutaneous flap model.

PURPOSE: Free tissue transfer is a powerful reconstructive surgical technique. The ischemia reperfusion injury (IRI) at revascularization affects the flap and the patient; reducing this insult could improve outcomes. This study evaluated the effect of C1 esterase inhibitor (C1-inh) on IRI in a porcine musculocutaneous flap model. MATERIALS AND METHODS: A musculocutaneous flap was transferred from the limb to the neck of 12 swine. Flaps underwent a 3-hour ischemic interval prior to revascularization. Intervention group flaps (n = 6) were perfused intra-arterially with 100U C1-inh at the commencement of the ischemic period; controls (n = 6) received heparinized saline solution. Protocol duration was 14 days; markers of reperfusion injury (creatine kinase [CK], aspartate transaminase [AST], tumor necrosis factor-alpha) were evaluated. RESULTS: All flaps from the intervention group were viable at 14 days; five of six control flaps were viable at 14 days (P = 1). Systemic levels of biomarkers of tissue necrosis and inflammation were reduced in the intervention group. On post-operative day one, statistically significant reductions in mean levels of AST and CK were demonstrated (2,293 ± 1 × 103 U/L vs. 1,586 ± 767 U/L [P = 0.04] and 429 × 103 ± 214 × 103 U/L vs. 213 × 103 ± 156 × 103 U/L [P = 0.002], respectively). Flaps of both groups healed in their recipient locations, no adverse reactions were observed. CONCLUSIONS: C1-inh is protective of IRI and may have utility in free tissue transfer, vascularized composite allotransplantation, and spare parts surgery. © 2016 Crown copyright. Microsurgery © 2016 Wiley Periodicals, Inc. Microsurgery 37:142-147, 2017.

A Porcine Orthotopic Forelimb Vascularized Composite Allotransplantation Model: Technical Considerations and Translational Implications.

BACKGROUND: The restoration of complex tissue deficits with vascularized composite allotransplantation is a paradigm shift in reconstructive surgery. Clinical adoption of vascularized composite allotransplantation is limited by the need for systemic immunosuppression, with associated morbidity and mortality. Small-animal models lack the biological fidelity and preclinical relevance to enable translation of immunologic insights to humans. Large-animal models have been described; however, limitations persist, including the inability of heterotopic models to evaluate functional nerve regeneration, and the sensitivity of primates to toxicity of immunosuppressive drugs. The authors' novel orthotopic porcine limb transplant model has broad applicability and translational relevance to both immunologic and functional outcomes after vascularized composite allotransplantation. METHODS: Recipients underwent amputation at a level corresponding to the mid forearm. Replantation or transplantation of grafts was performed by plate fixation of the radio-ulna, microsurgical repair of brachial artery and median nerve, and extensor and flexor tendon repairs. Viability of replants was monitored clinically and radiologically. Transplants were monitored for clinicopathologic signs of rejection. Animals mobilized freely postoperatively. RESULTS: Replantations remained viable until the endpoint of 14 days. Transplants developed Banff grade 4 acute rejection by postoperative day 7. Doppler sonography and angiography confirmed vascular patency. Serial biopsy specimens of skin and histopathology of replants at endpoint confirmed tissue viability and bone healing. CONCLUSIONS: An orthotopic load-bearing porcine forelimb vascularized composite allotransplantation model was successfully established. Technical, procedural, and logistic considerations were optimized to allow model use for immunologic, bone healing, functional nerve regeneration, and other translational studies.

High velocity gunshot injuries to the extremities: management on and off the battlefield.

The gunshot wounds sustained on the battlefield caused by military ammunition can be different in nature to those usually encountered in the civilian setting. The main difference is that military ammunition has typically higher velocity with therefore greater kinetic energy and consequently potential to destroy tissue. The surgical priorities in the management of gunshot wounds are hemorrhage control, preventing infection, and reconstruction. The extent to which a gunshot wound needs to be surgically explored can be difficult to determine and depends on the likely amount of tissue destruction and the delay between wounding and initial surgical treatment. Factors associated with greater energy transfer, e.g., bullet fragmentation and bony fractures, are predictors of increased wound severity and therefore a requirement for more surgical exploration and likely debridement. Gunshot wounds should never be closed primarily; the full range of reconstruction from secondary intention to free tissue transfer may be required.

Hydrogen sulfide mitigates reperfusion injury in a porcine model of vascularized composite autotransplantation.

BACKGROUND: Devastating extremity injuries are prevalent but often survivable on the modern battlefield. These complex injuries require advanced methods of reconstruction, involving prolonged ischemic periods and reperfusion injury. Using our group's validated porcine model of gracilis myocutaneous flap transplantation, this study demonstrates that an interim perfusion of hydrogen sulfide (H2S) mitigates the effects of reperfusion injury in the setting of delayed restoration of blood flow. METHODS: A gracilis myocutaneous flap (200-400 g; surface area, 250 cm²) was procured from the hind limb of a Yorkshire swine (70-90 kg, n=16). The right external carotid artery and the internal jugular vein are the recipient axis. Group 1 (control, n = 6) underwent delayed anastomosis with a 3-hour ischemic period. Group 2 (n=10) underwent a similar delayed anastomosis with an interim perfusion of H2S during the ischemic period. The animals survived for 14 days. Systemic biomarker assays for skeletal muscle tissue injury (creatine kinase, lactate dehydrogenase, and aspartate transaminase) and proinflammatory markers (tumor necrosis factor α and interleukin 6) provide assessment of reperfusion injury at the cellular level. RESULTS: The control animals (3 hours of ischemia with an interim perfusion of heparinized saline) demonstrated increased levels of injury biomarkers and proinflammatory cytokines compared with the animals receiving H2S infusion and identical ischemic interval. The control flaps had a mean creatine kinase level of 280³×10 U/L (±80×10³), compared with the H2S group, which had a mean of 99×10³ U/L (±14×10³; P=0.0007 at postoperative day 2). lactate dehydrogenase levels (mean) were 26×10³ U/L (±8×10³) versus 9×10³ U/L (±3×10³; P=0.0004) and aspartate transaminase levels (mean) were 1651 U/L (±324) versus (873 U/L [±279]; P=0.0013) for the control and treatment groups, respectively. Similarly, an intergroup difference in IL-6 was found, although not statistically significant. Tumor necrosis factor α levels (mean) were 93 pg/mL (±14) versus 39 pg/mL (±4; P=0.0013) for the control and treatment groups, respectively. CONCLUSIONS: This study demonstrated the mitigating properties of H2S on reperfusion injury. Interim perfusion with H2S resulted in diminution of ischemia-dependent biomarkers after 3 hours of ischemia. Follow-up studies will translate these findings as an evolving method for reconstructing previously unreconstructable injuries.

Use of topical negative pressure in british servicemen with combat wounds.

OBJECTIVE: The objective of this study was to characterize the use of topical negative pressure therapy in combat wounds. METHODS: This study was a retrospective review of the records of patients whose wounds were managed with topical negative pressure between April 2007 and March 2008. The main outcome measure was episodes of antibiotic prescription, which was used as a surrogate marker of clinically relevant infection. RESULTS: Of the 62 cases identified, 25 clinical notes were unavailable and were excluded from the study leaving 37 included cases. All but one of the cases was male with an average age of 29 (19-39) and New Injury Severity Score (NISS) of 21.3 (14.4-28.1). In 20 cases, topical negative pressure was changed less than once per 4.9 days on average, and in the remaining 17 cases, this was done more frequently. Comparison of the rate of antibiotic prescription between these groups reveals a significantly higher rate in the cohort managed with more frequent topical negative pressure changes. However this relationship was not borne out in a multiple variable analysis. CONCLUSION: This study describes the use of topical negative pressure in the management of a uniquely challenging group of patients. Statistical analysis of relatively small numbers is challenging but these results support the current complex wound management strategies where wounds are temporized with topical negative pressure for several days following thorough wound debridement. This period allows patients to be physiologically stabilized, other injuries to be addressed and appears not to be associated with increased infections.