PROSTHETIC REPLACEMENT IN THE TREATMENT OF LOWER LIMB BONE METASTASES: ANALYSIS OF 120 CASES

Abstract

The purpose of this study was to analyse the long-term results of prosthetic joint replacement in patients suffering from metastatic bone disease. The treatment was performed in order to prevent or treat pathological fractures, to control the pain and improve the functionality of the lower limb.

120 patients suffering from metastatic disease of the lower extremities were treated with prosthetic replacement between 1992 and 2004

The patients, 80 females and 40 males, having an age at the time of surgery ranging from 32 to 83 years, were treated by the same equipe in the San Raffaele Hospital in Milan.

The primary tumor included breast carcinoma (66), lung carcinoma (19), kidney tumor (17), prostatic tumor (7), plasmocytoma (5), non identified tumor (5), melanoma (1). The metastasis was located in the proximal femur in 112 cases, in the distal femur in 3, in proximal tibia in 5. In 8 out of 120 patients, the metastatic lesion was the first sign of carcinoma, 25 patients had a pathological fracture and the bone metastases were detected from 6 mounth to 13 years after the diagnosis of the primary tumor.

Knee: in our casuistry 8 patients with a metastasis in proximal tibia or distal femur were operated with modular prostheses: in 1 case of this group (single lesion of kidney tumor), we have implanted an allograft-prosthesis-composite.

Proximal femur: for the treatment of this site, we have included also those patients having a life expectancy inferior to 1 month. In 30 cases the lesion was located in the epiphysis and neck and we have implanted 5 endoprosthesis, 5 total hip prostheses and 20 bipolar prostheses. In 82 patients with a metastasis located in the metaphysis we used a modular prosthesis with a femoral resection up to 16 cm.

69 patients are alive with a follow-up ranging from 6months to 12 years. 5 patients died in early post surgical period. 13 patients developed local recurrence. These latest have suffered from a pathological fracture, which had occurred before the first surgical treatment. Pain relief was achieved in all patients after surgery with acceptable functionality of the operated limb.

We considered the risk of pathological fractures more important than life expectancy. Moreover, we believe that the surgery to these patients should be definitive. In fact, the use of prostheses allow for a wide resection of the lesion. This condition represents also an advantage in those cases where radio- or chemiotherapy can not be performed. Moreover, the prostheses permit an immediate weight bearing, a good functional recovery and also, in patients with critical general condition, a more easy assistance. In conclusion, for patients with metastatic bone disease, we consider a correct approach the radical excision of the lesion and the implant of a prosthesis.