Characteristics of endoprosthesis replacement of bones and joints in patients with metastatic lesions

Abstract

The article presents the results of endoprosthesis replacement of joints and bones in 19 patients with bone metastasis. The complications resulted from endoprosthesis replacement of joints and bones in cases of bone metastasis were observed in 4 (21.1 %) patients, and tumor recurrences were observed in 2 (10.5 %) patients. In the preoperative period, 19 patients underwent courses of external beam radiotherapy with a total radiation dose (TRD) of 40 Gray, with a single mediated dose (SMD) of 2–2.5 Gray. Also, all patients received preoperative multiagent chemotherapy treatment cycles depending on the primary source of the tumor, and in cases of hormone-dependent tumors, the patients received hormone therapy. Depending on the specific anatomical and functional changes, special implant designs, tools, and techniques were used, which complemented the standard technique of operations. The basic principles of oncosurgery have been adhered to during endoprosthesis replacement of joints and bones, i.e. standard principles of resection and ablastics, removing en bloc of a biopsy area. In endoprosthesis replacement, a cement type of endoprosthesis fixation was used. For an adequate formation of the muscle envelope of the endoprosthesis, a plastic stage of the ope-ration was performed, which allowed to adequately cover the installed endoprosthesis, and thus, reduce the risk of infectious complications. Both displaced and free vascularized musculocutaneous flaps on microvascular anastomoses were used as plastic material. To limit the contact of the metal part of the endoprosthesis with the surrounding tissues and to reconstruct the tendon ligamentous apparatus, a tube of polyethylene tetraphthalate was used, resected tendon and muscles were sutured to it, which allowed to more fully restore joint action. The functioning of extremity according to the MSTS scale after endoprosthesis replacement of joints ranged from 70 to 92 %, and also the quality of life of patients improved up to 70–75 points.