Background

A consecutive series of 76 patients (101 hips) underwent primary open reduction, capsulorrhaphy and innominate osteotomy for late presenting developmental hip dislocation. They were aged 1.5 to 5 years at the time of surgery between 1958 and 1965. This study was designed to review their outcome into middle age.

Introduction: A criticism of innominate osteotomy (IO) is that it causes relative acetabular retroversion, predisposing to OA. This study was designed to address this hypothesis.

Materials and Methods: We had access to radiographs of 30 patients 45 years after they had undergone open reduction and innominate osteotomy for late presenting DDH. Using the validated method of Hefti (1995) we measured anterior and posterior acetabular coverage, contact area and version.

Results: Group 1 – 26 Post-op hips, Group 2 – 20 Contralateral hips, Group 3 – 21 Normal hips. Anterior coverage was 10.8% in group 1, 11.0% in group 2 and 12.0% in group 3. Posterior coverage was 18.8% in group 1, 18.9% in group 2 and 21.0% in group 3. Contact area was 16.1 cm2 in group 1, 13.9 cm2 in group 2, and 22.1 cm2 in group 3. Version was 7.20 in group 1, 7.10 in group 2, and 7.70 in group 3.

A significant difference was found for contact area (p< 0.001). There was no significant difference in version (p = 0.845).

Conclusion: Early OA may be related to contact area. Any abnormal (retro)version grows out. Innominate osteotomy before the age of 5 years has the potential to facilitate, or at least not prevent, normal acetabular development and version.

We compared the effects of continuous passive motion with those of intermittent active motion on the results of the resurfacing with autogenous periosteal grafts of full-thickness defects on the articular surface of rabbit patellae. Of 45 rabbits with defects, 30 received grafts. Fifteen of these had continuous passive motion for two weeks and intermittent active motion for four weeks; the other 15 had intermittent active motion for six weeks. In 15 the defects were not grafted (control group) and they had intermittent active motion for six weeks. Ten more rabbits had a sham operation. Six weeks after surgery, the results were assessed by the gross appearance, histology, histochemistry, immunohistochemistry and electron microscopy. By all assessments the quality of neochondrogenesis produced by periosteal grafts was superior to that in ungrafted defects (p less than 0.05) and the results in continuous passive motion treated animals were superior to those in intermittent active motion treated animals (p less than 0.05). The periosteal grafts produced hyaline cartilage containing type II collagen but the organisation of its fibres was irregular.

Our purpose was to determine whether continuous passive motion enhanced the quality of knee ligament reconstruction using carbon fibre. In 46 rabbits the medial collateral ligaments were excised and replaced with carbon fibre prostheses. The animals were treated postoperatively by either continuous passive motion, cast immobilisation or cage activity, termed intermittent active motion. At six weeks, the ligaments were compared histologically and biomechanically with normal (control) medial collateral ligaments and with sham-operated controls. The ligaments treated with continuous passive motion were superior to those in the other two treatment groups. There were no ligament failures in any of the groups. This study suggests that continuous passive motion, initiated immediately postoperatively, enhances the biomechanical properties of carbon fibre ligament replacement of the medial collateral ligament while preventing the harmful effects of joint immobilisation.