Abstract After operative repair, the conventional management of open injuries to the middle slip of the extensor tendon involves prolonged immobilisation of the P.I.P. joint. We report our results using controlled mobilisation with a Capener splint after two weeks rigid splintage. In a series of 99 patients seen soon after injury, 88% had excellent or good results after six months. Poor results were more common in patients with complex joint injuries and in patients who did not comply with the treatment. We advocate early mobilisation following repair of the middle slip.