Pedicled transverse rectus abdominus myocutaneous (TRAM) flaps are the most common post-mastectomy breast reconstructive surgeries that utilize the patient's tissue. The pedicled TRAM flap involves harvesting skin, fat, and muscle from the abdomen to create a new breast. TRAM flap complications include fat necrosis of the reconstructed breast, delayed wound healing, and abdominal bulge or hernia. Pain at the abdominal donor site is a major contributor to the need for four to five days of post-operative hospital stay. Pulsed electromagnetic field (PEMF) technologies have been useful as adjunctive therapy for the treatment of delayed union fractures, chronic wounds and post-operative pain. PEMF devices are economical and disposable, and can be incorporated unobtrusively in standard post-operative dressings. The investigators have recently reported, in a double-blind, placebo-controlled study on breast reduction, that post-op PEMF therapy produced a significant decrease in pain and pain medication use, along with a concomitant decrease in IL1-beta in the wound bed.

The proposed study seeks to determine whether similar results will be obtained after a significantly more extensive surgical procedure, like the TRAM flap. Patients scheduled for pedicled TRAM flap breast reconstruction of a single breast immediately following mastectomy will be enrolled in this double-blind, placebo-controlled, randomized study. Subjects will be assigned to one of two groups: a treatment group with active PEMF devices and a placebo group with sham devices that deliver no PEMF. PEMF and sham devices will be taped over both the breast reconstruction and abdominal donor sites. Patients will keep the devices in place for their hospital stay and for a total of two weeks. The investigators hypothesize that subjects in the PEMF treatment group compared to placebo will have a faster reduction in pain, take less pain and nausea medications, have lower levels of IL1-beta in wound exudate, have a shorter hospital stay, and have less wound-healing complications.

Operations will be performed by one of two plastic surgeons who perform this surgery in a similar manner. The entire unilateral rectus abdominis muscle will be harvested with fascial-sparing as part of the pedicled TRAM flap. The flap will be shaped and sutured to the chest site, and the abdominal fascial defect will be closed primarily, followed by a polypropylene mesh overlay. Two 10 mm Jackson-Pratt (JP) drains will be placed in the flap wound, and two JPs will be placed in the abdominal wound. Immediately after transfer of the extubated patient to the recovery room bed, study devices will be placed on the reconstructed breast and abdominal donor sites, and activated. In the treatment arm, the PEMF signal is automatically delivered every two hours for fifteen minutes while the patient is in the hospital.

Inclusion Criteria:

• All patients who decide to have immediate unilateral TRAM flap breast reconstruction and are deemed candidates for this surgery. Patients who have undergone or will be undergoing sentinel lymph node or axillary lymph node dissection will be included.

Exclusion Criteria:

• Patients who are not candidates for TRAM flap reconstruction will be excluded. Specific reasons for a patient not to be a candidate will be determined by the surgeon, but may include patients who have minimal abdominal tissue, patients with multiple medical co-morbidities, patients who have had prior abdominal surgeries that preclude a pedicled operation, or patients who are morbidly obese.
• Additionally, patients who opt for a free TRAM flap or DIEP flap will be excluded since their abdominal donor site morbidity is different than a pedicled TRAM flap.
• Patients undergoing bilateral reconstruction will also be excluded, because of the more extensive nature of the surgery and donor-site morbidity, which might confound results.

Adverse event data was collected for the time period in which the PEMF device was in place post-operatively, usually less than 7 days post-op.