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.

The first part of this manual deals with the experimental and scientific basis and the principles of the AOjASIF method of stable internal fixation. It deals with the function and main use of the different AO implants, the use of the different AO instruments, and with the essentials of the operative technique and of postoperative care. It also discusses the handling of the most important postoperative complications. The second part deals at length with the AO recommendations for the operative treatment of the most common closed fractures in the adult. This has been organized in anatomical sequence. The discussion of the closed fractures is followed by a discus sion of open fractures in the adult, then by fractures in children and finally by pathological fractures. The third part presents, in a condensed fashion, the application of stable internal fixation to reconstructive bone surgery. 1 GENERAL CONSIDERATIONS 1 Aims and Fundamental Principles of the AO Method The Chief Aim of Fracture Treatment is the Full Recovery of the Injured Limb In every fracture there is a combination of damage to both the soft tissues and to bone. Immediately after the fracture and during the phase of repair, we see certain local circulatory disturbances, certain manifestations of local inflammation, as well as pain and reflex splinting. These three factors, that is, circulatory disturbances, inflammation and pain, when combined with the defunctioning of bone, joints and muscle, result in the so-called jl'acture disease.