[Surgical treatment of stiff massive knee endoprosthesis for bone tumors in children and adolescents]. / Traitement chirurgical de la raideur après prothèse massive du genou pour tumeur osseuse chez l'enfant et l'adolescent.

ABSTRACT

PURPOSE OF THE STUDY Improved oncologic outcome and technical advances in limb salvage surgery have made limb salvage therapy a feasible and valuable treatment option. Nevertheless, resection of a bone tumor followed by a reconstruction knee endoprosthesis can create gait abnormalities, of which one of the most frequent is knee stiffness. The aim of this retrospective study was to assess the outcomes of revision surgery for a stiff knee following reconstruction of a segmental long bone defect. PATIENTS AND METHODS: Between 1983 and 2005, 19 patients who had undergone wide resection of a tumor close to the knee followed by reconstruction with a massive endoprosthesis were revised for a diagnosis of stiffness. RESULTS: The mean age of the patients was 12 years (range 7-19 years). Patients were followed for a mean five years (range 1-21 years). Three patients were not assessed at the last follow up (two patients died, one patient was amputated for a local recurrence). The mean range of motion improved 80+/-24 degrees preoperatively to postoperatively. The Enneking score improved from 15+/-0.5 to 23+/-3 points at three months follow-up, and to 22+/-5 at last follow-up. Recurrent stiffness occurred three times and required a second operative release with a good final result. DISCUSSION: Outcome depends on the cause of the stiffness of the reconstruction knee arthroplasty. Stiffness can be caused by complications (trauma, implant failure, infection), and patient-related factors (lack of physiotherapy). Open arthrolysis is indicated for chronic stiffness in a motivated patient with an identified cause because failure to identify the cause of stiffness may result in recurrence of the problem.