BACKGROUNDS. Proximal femur reconstruction after removal of bone tissue due to various causes presents a major challenge for orthopaedic surgeons. One of the possible solutions is the Kent Hip endoprosthesis, which has been in use for 25 years. However, in
the literature, only short-term clinicalresults of this endoprosthesis implantation are reported with an average follow-up of maximum five years. Using a retrospective research study, we examined long-term clinical results of proximal femur reconstruction using the Kent
Hip endoprosthesis in comparison with primary hip endoprosthesis. METHODS. We examined 42 consecutive patients who underwent Kent Hip endoprosthesis implantation during the years 2001–2007. The control group consisted of 60 comparable patients. The analysis of demographic data (age, sex and body mass index) between both groups did not show any statistically significant differences (p ≥ 0.05). All 42 patients of the study group were divided into three subgroups according to the length of follow-up: with perioperative monitoring of up to 6 months, with short-term follow-up of 5 years and long-term monitoring over 5 years. RESULTS. During the analysis, 15 of the patients have died, 9 patients were lost to follow-up and 18 patients were still alive. The survival rate of Kent Hip endoprostheses is significantly shorter from the primary endoprostheses and Kent Hip patients have worse functional outcome (p = 0.03). Female sex (p = 0.02) and higher age at the time of surgery (p = 0.03) were associated with worse functional outcome. Mean follow-up is 10.1 years which is twice as high compared with the data reported in literature. CONCLUSIONS. Patients after the implantation of a revision-tumour endoprosthesis have a higher risk for complications after surgery when compared to patients with an implanted primary endoprosthesis. The Kent Hip endoprosthesis shows worse long-term results in the elderly and less mobile population than in active and younger patients.