The medial acetabular wall: normal measurements in different population groups.

Measurements of the acetabulum and particularly the medial acetabular wall were done on 90 skeletons. Mean and standard deviations for different population groups are presented. The purpose of this study was to establish the normal range of values for the thickness of the medial wall of the acetabulum. This information is of value for the radiologist and the orthopaedic surgeon in the pre- and intraoperative assessment of the bone reserve of the acetabular fossa in hip surgery.

Grey-white matter interface (G-WMI) displacement: a new sign in the computed tomographic diagnosis of subtle subdural haematomas.

Subtle and isodense subdural haematomas present difficult problems on computed tomography (CT). The diagnosis is based predominantly on secondary signs of mass effect. A new sign is described, based on the detection of medial displacement of the grey-white matter interface (G-WMI). The presence and validity of this sign was evaluated in 66 cases with surgically proven subdural haematomas (SDH).

Computed tomography in the assessment and planning of complicated total hip replacement.

Computed tomography (CT) proved useful in the assessment of 14 cases of failed and complicated total hip arthroplasty. CT provided information in the axial plane about the extent of joint pathology and particularly acetabular involvement. The information obtained proved of aid to the orthopaedic surgeon in the operative planning, indicating the best approach and whether bone grafting to the acetabulum was required. In spite of computer artifact created by metallic implants in the scanning field we found that the required information about the bony components of the joint could be obtained.

Normal axial anatomy of the hip as demonstrated by computed tomography.

The anatomy of four baseline transaxial computed tomography (CT) slices of the hip is described and compared with the corresponding anatomical cuts in cadavers. Level I demonstrates the superior compartment of the joint and the superior aspect of the femoral head. Level II is clinically the most important in that it demonstrates the bone thickness of the medial acetabular wall. Level III is through the femoral neck and allows measurements of femoral anteversion and acetabular inclination. The fourth level demonstrates the calcar femorale, but is seldom performed. An easy method of achieving reference levels II and III without a survey radiograph is described; the radiation dose can therefore be reduced by performing only the clinically relevant slice.

The 30 degree cephalad anteroposterior tilt view to stage avascular necrosis of the femoral head.

A 30 degree cephalad anteroposterior tilt view of the femoral head was used, in addition to standard radiographic projections, in 55 patients having, or suspected of having, avascular necrosis of the femoral head. This method was then compared with standard views. Five patients with questionable findings on standard projections showed definite avascular necrosis, and 10 thought on standard views to have grade 2 disease were found to be grade 3, all from use of the additional projection. This projection should form part of the evaluation of suspected avascular necrosis of the femoral head.

Computerized tomography of Castleman's disease simulating a false renal artery aneurysm: a case report.

We report a case of retroperitoneal Castleman's disease of the hyaline vascular type simulating a false renal artery aneurysm. Excretory urography with computerized tomography and angiographic findings are presented. All 3 investigations demonstrated a homogeneously enhancing hypervascular retroperitoneal mass.

Pituitary gonadotropin response to luteinizing hormone-releasing hormone (LH-RH) in males with azo- and oligospermia.

Twenty-one males with azo- or oligospermia presenting with infertility and with no evidence of organic disease were studied with luteinizing hormone - releasing hormone (LH-RH). A pituitary luteinizing hormone (LH) and follicle stimulating hormone (FSH) response was present in all cases and was normal in the majority of the subjects. Serum testosterone and 17 beta estradiol levels were normal in all cases studied. No significant correlations were found between the gonadotropin estimations and sperm count, basal serum testosterone or testosterone response to human chorionic gonadotropin. It is concluded that LH-RH is of limited diagnostic use in the investigation of this group of patients with male infertility and provides no further insight into the pathogenesis of this condition.

Diagnosis of acromegaly on cranial computed tomography.

The characteristic features of acromegaly as demonstrated on cranial computed tomography (CT) are described. These features relate to the increased soft tissue bulk and overpneumatization of sinuses and air cells, as well as the generalized bony overgrowth associated with high growth hormone (GH) levels. In the assessment of these features, the computer window settings must be adjusted accordingly for separate visualization of soft tissues, calvarial bones and cerebral tissue on the scan images. We found positive features in CT scans of 13 patients with established acromegaly and were able to suggest the diagnosis prospectively in 2 additional cases. The finding of an enlarged pituitary fossa should lead the radiologist to search carefully for the ancillary signs of acromegaly on the scans, thus confirming the diagnosis. When an enlarged sella turcica or an enhancing intrasellar mass is not demonstrated, the recognition of the other features on cranial CT scans may be important in suggesting the diagnosis of acromegaly to the clinician.

Radiography of healing dialysis osteodystrophy.

Characteristic skeletal changes of dialysis bone disease associated with multiple fractures were found in ten patients on prolonged regular (high aluminium) haemodialysis. A subsequent prospective investigation with serial radiography demonstrated healing approximately twelve months after a changed treatment regime. The treatment used was deionized or reverse osmosis water dialysis and renal transplantation. The typical osteomalacic and osteosclerotic changes and particularly metaphyseal sclerosis were found to be associated with more rapid clinical healing, whereas secondary hyperparathyroidism indicated delayed healing. It is suggested that plasma aluminium imbalance may lead to disturbance of bone formation with fractures, while healing is associated with normal serum aluminium levels and is manifested radiologically by osteosclerosis, particularly in the metaphyses.

Healing of fracturing-bone disease occurring in patients on dialysis. A prospective study.

Ten patients developed fracturing-bone disease (osteomalacia) while on dialysis against water with high levels of aluminium. Eight patients remained on dialysis, using de-ionized or reverse-osmosis water, and 2 received a renal transplant. Clinical improvement as regards bone pain and proximal muscle weakness occurred in 6 months and radiographic evidence of healing of the pseudofractures was seen at approximately 12 months. Associated osteopenia and hyperparathyroidism were found in most patients, but no significant change in either was noted during the study period. The serum parathyroid hormone levels rose significantly in the patients who remained on dialysis. The chest and pelvic deformities typical of healed osteomalacia were seen. This dramatic improvement can only be attributed to the removal of some water-borne element, either by changing the water used in the dialysis or by successful renal transplantation. Aluminium-containing phosphate binders were used throughout the study in the patients on dialysis, and hypophosphataemia was never a feature.

Pituitary-gonadal function in men with alcoholic cirrhosis of the liver.

Fourteen adult males with alcoholic cirrhosis were studied. Gonadotrophin responses to luteinizing hormone-releasing hormone (LRH) and testosterone (T) responses to human chorionic gonadotrophin (HCG) were determined and basal 17 beta oestradiol (E2) levels were measured in each case. The mean basal luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels, and the mean LH and FSH responses to LRH were not significantly different from a group of age-matched male controls. However, the five men with testicular atrophy all had an elevated basal FSH level and an exaggerated FSH response to LRH. The mean serum T of the cirrhotic men was significantly lower than that of the controls (P less than 0.05), while the mean E2 level was not significantly different. However, the mean E2 level in the eight patients with gynaecomastia was significantly higher than in those without gynaecomastic (P less than 0.05). All patients had a T response to HCG, including those 5 with low basal T levels. A significant negative correlation was found between the maximum rise in T after HCG (delta T) and the maximum LH response to LRH (delta LH), suggesting a mediating effect of T reserve on the LH response to LRH. These findings tend to exclude a suppressive effect of alcohol on the pituitary gland as a cause for the hypogonadism found in men with alcoholic cirrhosis. Furthermore, the evidence of some testicular T reserve despite low basal T levels, and the presence of normal basal LH levels, suggests that the low T production is not primarily due to leydig cell dysfunction.