- For patients with nonmetastatic tumors of the spine such as chordoma, total en bloc spondylectomy is a preferred technique for tumor excision
- Free vascularized fibula autograft (FVFG) is a reliable method for reconstructing the spine, but the graft can fracture in the lumbar spine, leading to instrumentation failure and the need for revision surgery
- In a novel technique developed at Massachusetts General Hospital, a femoral allograft sleeve is added to strengthen the reconstruction while retaining the osteogenic environment of the vascularized graft
- This case report describes the first use of this technique in a 65-year-old man who had a healed FVFG and femoral allograft with union at 18 months after surgery with no signs of recurrence or metastasis
For patients with nonmetastatic cancer of the spine, total en bloc spondylectomy is a preferred technique for tumor excision. Free vascularized fibula autograft (FVFG) is a reliable method for reconstructing the spine, but the graft can fail in the lumbar spine, where forces exceed those in the cervical and thoracic region. This can lead to instrumentation failure and the need for revision surgery.
Surgeons at Massachusetts General Hospital have devised a method—the addition of a femoral allograft sleeve—that strengthens the structure of the reconstruction while retaining the osteogenic environment of the vascularized graft.
John H. Shin, MD, director of Spinal Deformity & Spine Oncology Surgery in the Department of Neurosurgery at Mass General and Mass General Cancer Center, Michiel E.R. Bongers, MD, research fellow in the Department of Orthopedic Surgery, Sang-Gil Lee, MD of Orthopaedic Surgery, and Joseph H. Schwab MD, chief of the Orthopaedic Spine Center at Mass General and director of Spine Oncology & co-director of the Stephan L. Harris Chordoma Center at Mass General Cancer Center, and colleagues describe the technique as part of a case report in JBJS Case Connector.
Introduction to the Case
A 65-year-old man presented with a seven-month history of lower back pain and a five-month history of bilateral leg pain, without weakness or loss of sensation. The patient had undergone a course of physical therapy with no benefit and his back and leg pain symptoms progressed over time. Mass General surgeons diagnosed chordoma, a rare bone tumor, in the L4 vertebral body.
The patient's case was discussed with the Mass General multidisciplinary care team including specialists in radiation oncology, medical oncology and spine surgery. A strategy of pre-operative neoadjuvant proton-based radiation of 50.4 Gy was administered followed by additional adjuvant 19.8 Gy of radiation was delivered after en bloc resection. Published in the Journal of Neurosurgery, Mass General surgeons have shown that this protocol is associated with improved local control of chordomas.
The two-stage surgery is described in full in the article. The sleeve was added as follows:
- Once the FVFG was sized, the femoral allograft was cut and contoured to the length needed to fit between the endplates of L3 and L5
- A high-speed burr was used to hollow out the femoral allograft so it could accept the FVFG without compression of the vascular components, and a notch was created in one end of the allograft to allow the vascular leash of the FVFG to exit
- After allograft and autograft were determined to fit well together, they were held with a Verbrugge clamp while a Penfield probe was used to gently shoehorn them between the endplates of L3 and L5
- Anterior–posterior and lateral radiographs were obtained to check the position of the grafts
- 6 × 40 mm polyaxial screws were placed into the bodies of L3 and L5 through vertebral body staples, and rods were contoured to fit between the screws
- Additional compression around the graft was performed between L3 and L5 before all screws were tightened
- After the graft was manually inspected for adequate securing, the vascular leash was microscopically re-anastomosed to a branch from the aorta and a branch from the inferior vena cava
At one month after surgery, the patient's wounds had healed satisfactorily and he was walking with a rolling walker. At last follow-up, he continues to improve physically and functionally.
At 18 months after surgery, CT showed a healed FVFG and femoral allograft with union, with no signs of recurrence or metastasis.
Mass General surgeons have since performed this reconstruction in three other patients.
Learn more about the Department of Neurosurgery
Refer a patient to the Neurological Spine Service at Mass General