Kazuo Terayama

A LIPID METABOLIC DISEASE —“MEMBRANOUS LIPODYSTROPHY”— AN AUTOPSY CASE DEMONSTRATING NUMEROUS PECULIAR MEMBRANE-STRUCTURES COMPOSED OF COMPOUND LIPID IN BONE AND BONE MARROW AND VARIOUS ADIPOSE TISSUES

An autopsy case of a 38‐year‐old man demonstrating numerous peculiar membrane‐structures composed of compound lipid in the meta‐physis and marrow of long bones and various organs, where physiological hyperplasia ex vacuo of adipose tissue has occurred remarkably, is reported. The membranous structure was not observed in the brain while sudanophilic leucodystrophy was prominent.

Comparative Study of Total Hip Arthroplasty Between Younger and Older Patients

Ten- to 20-year (average, 14 years) results of primary Charnley low friction arthroplasties performed in patients 50 years of age or younger (55 sockets and 53 femoral prostheses) were compared with those in patients older than 50 years (273 sockets and 273 femoral prostheses). The incidence of radiologic loosening of the socket, including revision cases, was higher in the younger (29.1%) than in the older patients (14.3%). The revision rate for aseptic loosening of the socket was higher in the younger (20%) than in the older group (4%). This poor performance of the socket may be attributable to the higher incidences of rheumatoid diseases and accelerated polyethylene wear in the younger patients. In contrast, only 3.8% of the femoral prostheses were radiologically loose, and none of them were revised in the younger patients. These figures were comparable with those in the older patients. Quality or structure of bone available for implant fixation may be important for the durability of the arthroplasty. It was considered inferior on the acetabular side and better on the femoral side in the younger patients than in the older. Continued use of the cemented Charnley femoral prostheses can be justified in young patients, although further research is required for the socket problem.

A Radiological Population Study on the Ossification of the Posterior Longitudinal Ligament in the Spine

SummaryThis paper reports the results of a radiological population study on the ossification of the posterior longitudinal ligament (OPLL) in both the cervical and the thoracic spine among Japanese. The study was carried out in the Yachiho-mura district in the central part of Japan, where 5074 people were living. X-ray examinations were made of 1058 of the people; there were 440 men and 618 women, 50 or more years of age.The roentgenograms showed 34 cases of OPLL in the cervical spine (3.2%): 19 men (4.3%) and 15 women (2.4%). The condition was most frequently observed at the level of C-4. Radiological classification showed 18 cases of the segmental type, 11 of the continuous type, and five of a mixed type.There were eight cases of OPLL in the thoracic spine (0.8%), four in men (0.9%) and four in women (0.6%). OPLL in the thoracic spine was most frequently observed at the midthoracic levels. All eight cases showed a continuous type of ossification.There were three subjects with OPLL in both the cervical and the thoracic spine. Therefore, the number of subjects with OPLL in either the cervical or the thoracic spine was 39 (3.7%) total.

Arthroscopic reduction and fixation of a completely displaced fracture of the intercondylar eminence of the tibia

A simple method of arthroscopic reduction and fixation of a fracture of the intercondylar eminence of the tibia is described. A 23-year-old man with a completely displaced (Type IIIB) fracture was treated with arthroscopy. A satisfactory reduction was achieved by releasing the medial meniscus, which was entrapped in the fracture site. Link dynamic staples (W. Link, Hamburg, Germany) were used to firmly fix the fracture when the guide tube came downward from the medial mid-patellar portal. The secure fixation of the fragment and the prevention of the need for an arthrotomy facilitated early functional rehabilitation. One year after surgery the patient had a stable, painless joint with a full range of motion. The described method is technically straight-forward and can provide secure fixation of a bone fragment. The Link staples are useful in the fixation of a displaced fracture of the intercondylar eminence of the tibia.

Joint Space of the Human Knee and Hip Joint under a Static Load

In order to study the joint contact and joint space of statically loaded human knee and hip joints, observations of serial slices of joint specimens which were frozen during the application of a load were carried out. In the intact joints, the articular cartilage surfaces did not come into direct contact with each other even under a load of more than twice that of the body weight. The minimum distance between cartilage surfaces in each specimen ranged from 0.2 to 0.6 mm. The Indian ink which was injected into the joints before the load application was squeezed out of some areas of the remaining joint space, but a dye-free fluid apparently remained in this space.Based on our findings, the definition of joint contact and the lubrication mechanism in the intact human joint have been discussed.

Radiographic changes in wrists with ulnar plus variance observed over a ten-year period*

This study provides additional radiographic information concerning the long-term effect of ulnar impingement. Films of 198 wrists of 102 patients with vibration disease observed over ten or more years were reviewed. All the wrists showed ulnar plus variance of more than 0 mm except seven. Degenerative changes were found in 58 wrists and were seen only on the ulnar side of the wrist, especially in the ulnoproximal area of the lunate. Most of the degenerative changes in the wrists with ulnar plus variance had progressed or changed during the ten or more years. Ulnar plus variance may play an important role in inducing or causing progression of degenerative change in the wrist.

Factors influencing survivorship of the femoral component after primary low-friction hip arthroplasty

Two hundred sixty-seven consecutive primary low-friction arthroplasties, followed for 5-18 years after surgery, were studied to assess the factors influencing survivorship of the femoral component, using the Kaplan-Meier method. The end point of survivorship was defined radiographically in two ways: incipient failure (subsidence of the femoral component of > or = 2 mm) and definite failure (progressive change of position). Twenty-two femoral components developed incipient failure, and twelve of these advanced to definite failure. A canal filling ratio of the stem of > or = 75%, cement extent distal to the stem tip of > or = 1 cm, use of an intramedullary bone plug, and an exaggerated valgus alignment of the stem correlated positively with survivorship of the femoral component. Calcar resorption and atrophy of the femoral cortex after surgery were associated with aseptic loosening of the femoral component.

Long term bone remodeling around the Charnley femoral prostheses

Femoral bone remodeling after total hip replacement was studied by following patients who received 326 Charnley femoral prostheses for 10 to 20 years (mean, 13.3 years). The radiographic state of bone remodeling was visually assessed and measured with a digitizer. Demineralization that started proximally and then progressed distally caused cortical thinning, which correlated with widening of the intramedullary canal, not with changes that developed in the periosteal width, and occurred in the medial femoral neck, around the proximal half of the stem, and around the distal half in 87%, 33%, and 10%, respectively. Cortical thinning around the distal half of the stem was always accompanied by proximal thinning, and extensive cortical thinning (both proximal and distal) correlated with both lower clinical scores and radiologic loosening of the femoral prosthesis. A low canal flare index of Noble, a large canal width, and a patient age of 60 years or more were risk factors for extensive cortical thinning. Accelerated polyethylene wear was related to resorption of the medial femoral neck but not to cortical thinning or radiological loosening. Cortical thickening occurred only around the distal half of the stem in 29%. These findings establish a basis for the performance of cemented femoral prostheses, and allow comparison of bone remodeling when evaluating other femoral prostheses.

Neurofibromatosis with spinal paralysis due to arteriovenous fistula.

SummaryA case of neurofibromatosis with spinal paralysis due to arteriovenous fistula is reported. Preoperatively, the appropriate diagnosis was missed because angiography had not been performed. Post-operative angiography disclosed that an arteriovenous fistula formed a tumor-like mass, and that a part of the mass had invaded the spinal canal, compressing the spinal cord. It is concluded that the possibility of an arteriovenous fistula should be kept in mind in neurofibromatosis patients with spinal cord symptoms.

Fracture of the tibial tray following PCA knee replacement

We report two cases in which fracture of the tibial metal tray was thought to be due to improper design of the tray and heavy polyethylene wear. The bone beneath the fractured portion of the tray was deficient and had been replaced by granulomatous fibrous tissue including numerous polyethylene wear particles and foreign-body giant cells. Osteolysis occurred as a tissue reaction to these particles.