Tendons are strong cord like structures which start from fleshy belly of muscles and are inserted onto bone on which the action of muscle is intended. Integrity of tendon-muscle unit is very important for any movement of the joint on which acts. The lack of function of muscle-tendon unit can be due to variety of reasons like injury to nerve supplying the muscle leading to paralysis of the muscle, injury to tendon leading to its discontinuity, tendon getting stuck in a scar tissue etc. Tendon trasfer is one way to treat this probem with good results. The operation aims to utilise a separate, working muscle tendon unit, a donor tendon to achieve the function of nonworking muscle. Usually the donor muscle is selected in such a manner that changing it's original function to a new one does not cause a functional deficit. For example, in the case cited here an expendable muscle was harvested whose original function is to straighten index finger. Nature has designed 2 muscles which do the same job of making the index finger straight, hence even if 1 is utilised the other still straightens the finger. In this case the tendon responsible to make thumb straight was torn as a long term complication of a previous surgery performed for fracture done by different surgeon.