Secondary Surgery for Functional Improvement After Hand Transplantation

Orthotopic forelimb transplantation in a Yucatan minipig model: Anatomic and in vivo study

INTRODUCTION

Above elbow transplants represent 19% of the upper extremity transplants. Previous large-animal models have been too distal or heterotopic, did not use immunosuppression and had short survival. We hypothesize that an orthotopic forelimb transplant model, under standard immunosuppression, is feasible and can be used to address questions on peri-transplant ischemia reperfusion injury, and post-transplantation vascular, immunologic, infectious, and functional outcomes.

MATERIALS AND METHODS

Four forelimbs were used for anatomical studies. Four mock transplants were performed to establish technique/level of muscle/tendon repairs. Four donor and four recipient female Yucatan minipigs were utilized for in-vivo transplants (endpoint 90-days). Forelimbs were amputated at the midarm and preserved through ex vivo normothermic perfusion (EVNP) utilizing an RBC-based perfusate. Hourly perfusate fluid-dynamics, gases, electrolytes were recorded. Contractility during EVNLP was graded hourly using the Medical Research Council scale. EVNP termination criteria included systolic arterial pressure ≥115 mmHg, compartment pressure ≥30 mmHg (at EVNP endpoint), oxygen saturation reduction of 20%, and weight change ≥2%. Indocyanine green (ICG) angiography was performed after revascularization. Limb rejection was evaluated clinically (rash, edema, temperature), and histologically (BANFF classification) collecting per cause and protocol biopsies (POD 1, 7, 30, 60 and endpoint). Systemic infections were assessed by blood culture and tissue histology. CT scan was used to confirm bone bridging at endpoint.

RESULTS

Animals 2, 4 reached endpoint with grade 0-I rejection. Limbs 1, 3 presented grade III rejection on days 6, 61. CsA troughs averaged 461 ± 189 ng/mL. EVNLP averaged 4.3 ± 0.52 h. Perfusate lactate, PO2 , and pH were 5.6 ± 0.9 mmol/L, 557 ± 72 mmHg and 7.5 ± 0.1, respectively. Muscle contractions were 4 [1] during EVNLP. Transplants 2, 3, 4 showed bone bridging on CT.

CONCLUSION

We present preliminary evidence supporting the feasibility of an orthotopic, mid-humeral forelimb allotransplantation model under standard immunosuppression regimen. Further research should validate the immunological, infectious, and functional outcomes of this model.

Special Considerations for Secondary Surgery After Upper Extremity Transplantation

BACKGROUND

Upper extremity (UE) transplantation is a complex undertaking that may require emergent or elective secondary surgery (SS) days to years following transplant. Various patient and transplantation may help determine what SS is needed. In this study, we characterize the SS needed by our UE transplant patients.

METHODS

We retrospectively reviewed 6 patients who underwent hand and UE transplantation by one of the authors. Transplantation and SS details were obtained from medical records. Hand and arm function was quantified both subjectively (patient-reports) and objectively (Disabilities of the Arm, Shoulder, and Hand Score; Carroll test; Action Research Arm Tests; Box and Block test).

RESULTS

Six patients underwent transplantation for a total of 10 transplanted limbs. Five transplants were performed below and 5 above the elbow. Mean time post-transplantation at last follow-up was 5 years (range: 1-9 years). In all, 66.7% of the patients required SS: total 7 surgeries comprising 13 procedures. The most common procedures were to improve hand function-nerve decompressions and tendon transfer, both in above-elbow transplant. Both patients showed a mean improvement of 15 points on Carroll scores. One above-elbow transplant had a brachioplasty for excess skin and another had a hematoma evacuation immediately after transplantation. Procedures in the below-elbow transplants included multiple incision and drainages for a septic wrist and an open reduction and internal fixation for a forearm fracture.

CONCLUSION

Patients receiving UE transplantation often require one or more secondary procedures which may vary with level of transplantation. Secondary surgery should be an important aspect of pretransplant planning and cost-effectiveness determinations.

LEVEL OF EVIDENCE

Level IV.

Outcomes after hand and upper extremity transplantation

Hand and upper extremity transplantation (HUET) has emerged as the most frequently performed reconstructive procedure in the burgeoning field of vascularized composite allotransplantation (VCA). VCA refers to a form of transplant with multiple tissue types that represents a viable treatment option for devastating injuries where conventional reconstruction would be unable to restore form and function. As hand transplantation becomes increasingly more common, discussions on advantages and disadvantages of the procedure seem to intensify. Despite encouraging functional outcomes, current immunosuppressive regimens with their deleterious side-effect profile remain a major concern for a life-changing but not life-saving type of transplant. In addition, a growing number of recipients with progressively longer follow-up prompt the need to investigate potential long-term sequelae, such as chronic rejection. This review will discuss the current state of HUET, summarizing outcome data on graft survival, motor and sensory function, as well as immunosuppressive treatment. The implications of these findings for VCA in terms of achievements and challenges ahead will then be discussed.

Hand and upper extremity transplantation: an update of outcomes in the worldwide experience

BACKGROUND

Hand/upper extremity transplantation is the most common form of vascularized composite allotransplantation performed to date. An Update of worldwide outcomes is reported.

METHODS

The authors summarize the international experience with 107 known transplanted hand/upper extremities in 72 patients. Data from published medical literature, national and international meetings, lay press reports, and personal communications were utilized to provide the most up-to-date summary.

RESULTS

Although 24 losses (including four mortalities) are known, three of the four reported mortalities and eight of 24 limb losses were caused by multiple type vascularized composite allotransplantations (combined upper and lower limb or upper limb and face). Seven more losses were attributable to 15 patients in the early experience in China. In the United States and Western Europe, only three other non-acute graft losses have been reported, resulting in a patient survival rate for unilateral or bilateral hand transplantation in isolation of 98.5 percent and an overall graft survival rate of 83.1 percent.

CONCLUSIONS

Published functional outcomes continue to demonstrate improvement in function and quality of life. The international experience supports the idea that, for properly selected individuals, hand and upper extremity transplantation should be considered an important treatment option.