A study on occurrence of third trochanter in the femora in northern Tamil Nadu region

Background and aims: The third trochanter is defined as the osseous tubercule in the superior part of the gluteal tuberosity. The occurrence of third trochanter might have been due to the consequence of the relative strengthening of gluteus maximus muscle in human beings. The present study was undertaken on the femora of northern Tamil Nadu region with the aim to determine the frequency of third trochanter of femur in this region and to compare it with occurrence in other series. Material and methods: The study was carried out on a collection of 153 dried adult femora of unknown age and sex available at the departments of Anatomy of Annapoorana Medical College and Vinayaka Mission's Homeopathy Medical College, Salem, Tamil Nadu, India. Results: Out of total 153 femora studied, the presence of third trochanter was noticed in 21 femora (13.72%). Out of these 15.71% were femora of the right side and 12.04% were of the left side. The average length and breadth of the third trochanters were 19.80±5.22 mm and 7.63±1.75 mm respectively Conclusion: The occurrence of the third trochanter was considerably higher among right femora than the femora of the left side. The average length of the third trochanters was found to be more on the right side and average width was more on the left side. This may be due to functional difference between the right and left gluteus maximii muscles.