INCIDENCE, TREATMENT AND OUTCOME OF INFECTION IN MAJOR SURGICAL PROCEDURE IN SKELETAL ONCOLOGY

Abstract

Purpose: Aim of this study was to analyse the incidence of infection in orthopaedic oncology after major surgical procedures for bone tumors.

Materials and Methods: We included patients with primary sacral tumors treated by major surgical procedure and patients with bone tumors of the upper and lower limb treated by resection and prosthetic reconstruction. Demographic data, surgery, adjuvant treatments, type of reconstruction were analyzed. Special attention was given to the infection: incidence, classification, microbic agents, treatment and outcome. Infections in the first 4 weeks were considered “postoperative”, those in the first 6 months were judged “early”, while “late” those diagnosed after 6 months. Overall 1462 patients treated in one institution from 1076 to 2007. Were considered 1036 patients with tumors of the lower limb, 344 patients with tumors of the upper limb and 82 sacral tumors. Univariate analysis with Kaplan-Meier actuarial curves was used in evaluating risk factors and implant survival to infections.

Results: In the lower limb, infection occurred in 80 cases (7.7%). Most frequent bacteria were gram positive. Infection was postoperative in 9 cases, early in 12, late in 59 cases and generally monomicrobial. Surgical treatment was “two stage” in 73 patients, “one stage” in 4 and primary amputation in 3 cases. Revisions for infection were successful in 63 pts (79%), while 17 pts were amputated (21%).

In the upper limb, in 20 patients (5.8%) a revision for deep infection was required. Two infections were postoperative, 7 early and 11 late. S. Epidermidis and S. Aureo were the most frequent bacteria causing infection (45%). “Two stage” treatment of infection was performed, but a new prostheses was implanted in 3 cases. In 17 the spacer was never removed.

In the sacrum, no deep infections were observed after intralesional excision for giant cell tumors. In 23/52 resections (44%) for chordoma (3 pts. died postoperatively and were excluded), infection occurred: in 16 patients postoperatively, in 7 within 6 months. Bacteria causing infection were mostly gram negative: in 74% of cases infection was multiagent. Surgical treatment consisted in one or more surgical debridements with antibiotics therapy according to coltures: infection healed in all cases.

Conclusion: Infection is a severe complication in prosthetic reconstructions for tumors of the upper and lower limb. Its incidence in the extremities (7.7% and 5.8%) is lower than after sacral surgery (44%). Infections are mostly late, monomicrobial and caused by gram positive in extremities, while early, multimicrobial and caused by gram negative in the sacrum.