Limb Salvage Through Tissue Engineering: A Novel Treatment Modality Using Dehydrated Human Amnion/Chorion Membrane

Limb Salvage Through Tissue Engineering: A Novel Treatment Modality Using Dehydrated Human Amnion/Chorion Membrane

Extremity wounds with exposed critical structures, including bone and tendon are a major burden on the American healthcare system with limited treatment options. Free Flap reconstructions of lower extremity wounds have an increased failure rate in comparison to elective free flap procedures.These procedures are long and are associated with a high cost of care, prolonged hospital stays, and are limited by the need for surgical specialist availability and patient vessels suitable for anastomoses. This study will use a new treatment modality which is a commercially ready human amniotic membrane allograft (EpiFix) to promote a granulation tissue wound base that will be suitable for skin grafting, thus forgoing the need for a flap-based for reconstruction. The study goals are to reduce the overall cost of providing definitive treatment by decreasing operative time, length of hospital stay, decrease the need for intensive nursing care and rehabilitation. This study will aim to provide a treatment option that is readily accessible to all patients with these complex wounds in any healthcare setting across the country.

53 patients ages 18 and over , presenting with wounds with exposed critical structures (bone and/or tendon) will be enrolled in the study and randomized into one of two groups. 21 patients will be in the standard treatment group (Flap based reconstruction) and 32 patients will be in the dHACM (EpiFix) + skin grafting treatment group (Experimental). Exclusion criteria includes exposed implanted hardware (surgical plates), anticipated need for future surgical procedures through the same wound, wounds resulting from surgical removal of malignancy, and patients who are not free flap candidates.

Data will be collected upon enrollment including:

Background and demographic information Wound size and severity Pain level Medication use Photographs of wound

Flap Reconstruction group (Standard of Care):

Patients in this group will have any dead, damaged or infected tissue removed from the wound and a negative pressure wound dressing will be applied until the wound is clean and adequate for flap reconstruction. Following flap reconstruction, patients typically require a 36-48 hour intensive care unit admission for flap monitoring and 5 days to bed rest to allow for proper healing. If the flap is successful, a dangle protocol will occur until patient increases the dependent position. Once the dangle protocol is completed, patients may require inpatient physical/occupational therapy prior to discharge from the hospital. If patient is not healing the physician may discuss other treatment options including crossing over to the EpiFix arm or amputation.

EpiFix and Skin Graft group:

Patients in this group will have any dead, damaged or infected tissue removed from wound. Once it is free from infection, a thin tissue (EpiFix) will be applied directly to the open wound. This will be covered by sterile wound dressing. After approximately 5-7 days the wound will be assessed for suitability of split thickness skin grafting. If adequately healed, skin grafting will be performed. After 5 days, the graft will be evaluated and if successful, the patient will be discharged home or to a rehab facility. If the wounds are not adequate for skin grafting, additional damaged tissue will removed and EpiFix will be placed until the wound is suitable for grafting. If you do not heal sufficiently the physician will discuss other treatment options including cross over to the standard of care Free Flap or amputation.

Study staff will evaluate the wound twice a week for the first 2 weeks, then once a week until 6 weeks. At this point, the patient will be followed every 4 weeks up to 22 weeks. Visits to the clinic will include wound measurements, photos, pain scale and evaluation of any infection.

Inclusion Criteria:

• Wound includes exposed critical structures (tendon and/or bone)
• Patient is candidate flap reconstruction
• Patient is candidate for limb salvage

Exclusion Criteria:

• Wound involves weight-bearing surfaces (e.g. heel or forefoot wounds),
• Exposed implanted hardware (e.g. surgical plates)
• Anticipated need for future surgical procedures through the same wound
• Wounds resulting from surgical removal of malignancy
• Patients who are not flap candidates (e.g. severe peripheral vascular disease)
• Patients who are not limb salvage candidates (e.g. insensate or ischemic limbs).