Pathologic hip fractures with signs of metastatic disease pose challenges

A top surgeon shares treatment tips, including when to recommend joint replacement

Issue: March 2006

ORLANDO, Fla. — Surgery can dramatically improve quality of life for patients with pathologic hip fractures. But before intervening, orthopedic surgeons should watch for signs of metastatic disease and immediately refer appropriate patients to an orthopedic oncologist, according to a surgeon speaking here.

Mary I. O’Connor, MD [photo]
Mary I. O’Connor

“These [cancer] patients typically need postoperative radiation, maybe some chemotherapy, and have other pain management issues,” Mary I. O’Connor, MD, a specialist in tumor surgery at the Mayo Clinic in Jacksonville, Fla., said at the 22nd Annual Current Concepts in Joint Replacement Winter 2005 Meeting.

Pathologic hip fracture patients typically have progressive pain that is not relieved by rest and which is more pronounced at night. Most patients do have a history of cancer. But among the many new cancer patients in the United States each year, 10% to 15% will visit orthopedic surgeons for bone metastases without a prior cancer diagnosis, O’Connor noted.

“Remember patterns of referred pain. Consider the possibility of a pathologic fracture in somebody with acute pain and minimal trauma. And if you see an avulsion fracture in the lesser trochanter, that’s almost pathognomic of metastatic disease,” she said.

Xray 1
This patient never had hip surgery, but radiation to treat his prostate cancer damaged his femoral heads. He had acetabular erosion, massive bone loss and chronic pain.

Xray 2
O’Connor treated the patient with staged total hip arthroplasty. He had sufficient bone, so she was able to use trabecular metal. At one year postop, he is doing well.

Courtesy of Mary I. O’Connor

When evaluating patients with persistent pain, orthopedic surgeons should consider repeating radiographs and obtaining a total body bone scan. If a solitary bone lesion is identified, O’Connor suggests referring that patient to an orthopedic oncologist. “If the patient has a solitary bone lesion, it’s a sarcoma until proven otherwise, even in the patient with a history of cancer,” she said.

In patients with multiple bone lesions and a history of cancer, a presumptive diagnosis of metastatic disease is typically reasonable. In such patients, those with an impending or actual pathologic fracture will benefit from operative treatment, she said. “We would send tissue [from the lesion] at the time of surgery ... to confirm the diagnosis,” she noted.

It is best to refer patients with metastatic renal or thyroid tumors because such patients have highly vascular lesions. Before proceeding with surgery, the surgeon should be prepared to handle extensive blood loss and be able to preoperatively embolize their tumors, O’Connor said.

Focus on early function

O’Connor noted that because pathologic hip fracture patients have limited life expectancies, surgeons should focus reconstruction on providing early function. For acetabular fractures, “the reconstructive principle is to transmit stress away from the diseased bone to the intact bone. You cannot just fill a moderate defect with cement; this will fail. Cages and specialized techniques are often necessary.”.

For femoral neck lesions or fractures, O’Connor favors cemented bipolar or unipolar arthroplasty because it allows early weight bearing and pain relief, and lowers the risk of tumor progression and fixation failure. She noted that cemented stems are appropriate because these patients typically require postoperative radiotherapy.

When the disease extends from the femoral neck to the inner trochanteric region, she prefers a calcar replacement. But extensive bone loss in the proximal femur requires a proximal femoral replacement. Surgeons can also use internal fixation if the patient has adequate bone in the periacetabular and subtrochanteric regions.

“If you’re going to use internal fixation, [consider] a … recon nail, because it allows prophylaxis of the femoral neck and shaft,” O’Connor said.

Patients with prior pelvic irradiation usually have fractures and osteonecrosis. They also exhibit mechanical insufficiency, and have a high failure rate for standard reconstructions. These patients may need specialized acetabular reconstructions and are at a higher infection risk, she said.

For example, O’Connor cited a 74-year-old man who had prior radiation for prostate cancer that severely damaged his femoral heads. The patient had acetabular erosion, massive bone loss and was confined to a wheelchair. O’Connor performed staged hip replacements and used trabecular metal acetabular components. “He’s a year out now, still doing well. Walking with a cane. But I’m keeping my fingers crossed on the sockets because there was significant acetabular bone loss. A cage could also be considered in this patient,” she said.

For more information:
O’Connor M. Pathologic hip fractures: A class of their own. #19. Presented at 22nd Annual Current Concepts in Joint Replacement Winter 2005 Meeting. Dec. 14-17, 2005. Orlando, Fla.