All methods were first assessed in a human cadaver model before implementation in the clinical setting. In concert with our radiation oncologist and radiation physicist, we mapped the relationship of the target tumor to the medial tip of the greater trochanter using a pre-operative CT scan.  Simultaneously, the radiation oncologist and the radiation physicist created a radiation map to treat the known tumor burden.

Surgery was performed in specialized intraoperative radiation therapy operating theatre. A Smith and Nephew antegrade femoral nailing system was utilized (Smith and Nephew, Memphis, TN), as were two 3.5mm cannulated drill bits with kirschner-wires, and brachytherapy catheters with fiducials.

The patient was positioned in a lateral position on a bean bag, in a slight decubitus position to allow for ease of lateral radiographs.  Preoperative radiographs were taken using a C-arm to localize the lesions and to check for adequate visualization of the whole bone.  Skin markings were drawn to superficially localize the tumor.

Skin incision was performed proximal to the tip of the greater trochanter.  The 1.9mm k-wire was introduced into the appropriate start point on the greater trochanter and advanced to the level of the lesser trochanter.  The cannulated drill bit was introduced taking care to avoid the peritumor region with the drill bit. The second cannulated drill bit was introduced into the wound and placed next to the first at the tip of the greater trochanter.  Appropriate positioning was confirmed using fluoroscopy. The difference was measured on the field providing the surgeon with the exact measurement of the length of drill bit inside of the bone.

The guidewire was removed and replaced with the appropriately sized brachy-catheter with radiopaque markers which was advanced to the target position. The radiation oncologist confirmed placement of brachytherapy catheter and confirmed no blood, contaminant, or kinks were found therein. The catheter was then secured to operative field and attached to intraoperative radiation therapy afterloader device. Radiation physicists confirmed safety and ready position of device. At this point in the procedure, the surgeons and all operating room personnel left the operative suite and the patient received planned intraosseous radiation dose.  After radiation was completed, we proceeded with IMN placement. We utilized the reamer irrigator aspirator (RIA) (DePuy Synthes, Warsaw, IN) for a one pass reaming and removal of intramedullary tumor burden. The IMN was placed in standard fashion with a single cephalomedullary screw and a single distal interlocking screw.

IMBT was then performed on a 56-year-old female with metastatic melanoma and impending fracture to the left femur with three lesions visible on radiographs and MRI. We cannulated her femoral canal, placed the brachytherapy catheter in the appropriate location and sequentially irradiated the tumors with a goal peripheral dose of 20 Gy.  After her radiation treatment, the brachytherapy catheter was removed and IMN was placed. We encountered no complications. She was ambulating post-operative day one and discharged post-operative day three. She recovered without any wound complications, no evidence of associated fibrosis, or any nerve damage four months post-operatively. She continued to ambulate with a walker. Unfortunately, she developed further disease and died of progressive metastatic melanoma 4 months 28 days post-operatively.