Knee arthrodesis following prosthesis removal. Use of the Wagner apparatus

Arthrodesis after the removal of a knee prosthesis is often hampered by the small area of contact of the bony surfaces and by pre-existing infection. Conventional systems of external fixation and compression frequently fail to achieve stability but the addition of the Wagner leg-lengthening apparatus applied anteriorly and adjusted to give compression ensures rigid external fixation. Four knees in four patients were treated using this technique; the treatment followed the removal of infected prostheses in three knees and painful fibrous ankylosis after the removal of the prosthesis in the other. All obtained a sound arthrodesis.