J. SCHATZKER Friedrich Pauwels first postulated that excessive osteotomies and in particular on a group ofJ 09 joint pressure could cause the destruction of ar- osteotomies followed up for 13-15 years after ticular cartilage and lead to osteoarthritis, and surgery. that the reduction of this pressure would bring Erwin Morscher supports the long-term re- about regeneration of articular cartilage and re- sults of Bombelli and Schneider in his analysis gression of the disease. The first chapter of this of a study of over 2,000 osteotomies performed book is a synthesis of Pauwels' lifelong devotion in several Swiss centers. to the biomechanics of the hip. It presents the He also presents a careful analysis of his reader with a clear exposition of the intertro- own smaller series. Based on all these data, he chanteric osteotomy as a procedure based on defines for us the ideal parameters which clear biomechanical principles, and illustrates should be present in order to make the patient how biomechanical regeneration of the joint can an ideal candidate for an intertrochanteric os- be influenced by a reversal of the mechanical teotomy.