1. An operation is described for ischio-femoral extra-articular arthrodesis of the hip joint by posterior open approach, based on the techniques of Trumble and Brittain.

2. The operation has the advantages of affording adequate exposure of the sciatic nerve trunk and permitting visual control of the alignment and penetration of the chisel and graft.

3. The operation has been performed successfully without serious shock or subsequent complications in eighteen cases, mostly of tuberculosis of the hip.