INTERCALARY SPACERS IN THE TREATMENT OF SEGMENTALLY DESTRUCTIVE DIAPHYSEAL HUMERAL LESIONS IN DISSEMINATED MALIGNANCIES

During a 10-year period, 17 patients with segmentally destructive bone lesions of the humeral diaphysis in disseminated malignancies resulti ng in impending fracture (8 patients), pathologic fracture (6 patients ), or failure of attempted internal fixation techniques (3 patients) w ere treated with resection of the involved diaphyseal segment and reco nstruction with a cemented modular intercalary humeral spacer, Fourtee n patients had metastatic cancer, 2 had multiple myeloma, and 1 had ly mphoma, Breast and renal carcinoma were the most common pathologic dia gnoses, The involved site was within the middle 1/3 in 8 patients, in the proximal-middle junction in 5, in the middle-distal junction in 2, and within the proximal and distal 1/3 in 1 patient each, Early pain relief was successful in 88% of patients, Early in the postoperative h ospital course, patients generally were able to use the ipsilateral ha nd to assist feeding, Radiographic analysis revealed that the limited selection of stern lengths led to 76% of the distal stems and 47% of t he proximal sterns being shorter than the ideal length, The complicati on rate independent of disease progression was 29%. The most common co mplication was temporary radial nerve injury (3 patients), There were 3 implant failures, most commonly due to disengagement of the male-fem ale junction, Two periprosthetic fractures occurred, 1 proximally (due to tumor progression) and 1 distally. Suggestions are given for modif ication of the implants to improve the major problems of limited versa tility in intramedullary stem length and inadequate mating at the junc tion.