Shanmuganathan Rajasekaran (S. Rajasekaran) is an Indian Orthopedic Spine Surgeon. He is known for his work in spine tuberculosis, spine deformity corrections, and disc research.

He is the chairman of the department of orthopaedics & trauma and spine surgery division of Ganga Medical Centre and Hospitals, Coimbatore.

Rajasekaran was the Hunterian Professor and Honorary Fellow of the Royal College of Surgeons of England