Abstract
During the past 12 years, studies on clinical and surgical findings in CDH and on excised ligamentum teres examined by means of light microscope (LM) and scanning electron microscope (SEM) were performed on 63 hip-joints of 60 patients with surgically treated CDH. The following clinical results were obtained: many of the patients brought to us were too old (mean age 12.3 months) ; almost 80% of the acetabulum of patients received operations were of the flat-sharp type or the protruding type; a reratively high portion of cases (24%) needed adjustment operation because a centripetal position could not be achievd by open reduction alone. With respect to the relationship between previous treatments and deformation of the femoral head, some deformation, in which ligamentum teres seemed to be concerned, were observed in three groups, two treated with Pavlik harness (Riemenbügel: RB) and overhead traction (OHT), and one group which had received no treatment. Other groups treated with plaster fixation, etc., Histologically, the ligamentum teres could be classified into three parts; zone I (proximity of the apex), zone II (intermediary of the ligament), and zone III (base of the ligament) . In zone I, histopathologic changes were observed mainly in chondroid tissues, in zone II, in connective tissues and in zone III, in vascular system. The age and various treatments caused the different histological changes in the ligament, which were chiefly observed in connective tissues with vascular changes throughout all zones or in some parts of a zone, or with no vascular changes. SEM revealed wavelike structures of the ligamentum teres, showing suitable structures for joint movement. Histologically degenerating ligaments had no fibrous structures, indicating that these changes could not be thought of as reversible, and that they might affect cartilaginous tissues on the femoral head during early developing processes. Accordingly, the RB method and OHT are preferable for treating CDH, because they affect less the ligaments.
