The fracture of the biggest sesamoid bone patella is encountered at a rate of 1% of all skeletal injuries. Partial patellectomy is advised in the treatment of comminuted fractures of patella. In this retrospective study, we evaluated 18 of 25 patients who had partial patellectomy in our clinic between 1986-1997. Five patients were female (%27.8) and 13 were male (%72.2). The mechanisms of injuries were as follows: 11 (%61) motor vehicle accidents; 4 (%22) falls from flat-roofed house; 2 (%11) gunshot; and 1 (%5) subsidence. The mean age of the patients was 34.3 (range, 13-65). Ten left (%55) and eight right (%45) partial patellectomy were performed. Ten (%55) patients had also additional pathologies. The median follow-up time was 5.2 years (range, 2-11 years). Patients were very well in the last follow-up. According to Cincinnati Knee Score, which was improved by Noyes, 5 patients (%30) had excellent, 8 (%42) good 3(%17) moderate and 2 (%11) bad results. In conclusion, in the following years, enlargement in patellar articular surface and ossification, which is developed compensationally in the extensor mechanism may be detected and misevaluated as osteoarthrosis. Hence, we determined that they had not restricted knee joint functions in our cases.