A longitudinal study of MARS MRI scanning of soft-tissue lesions around metal-on-metal total hip arthroplasties and disease progression.

We investigated the changes seen on serial metal artefact reduction magnetic resonance imaging scans (MARS-MRI) of metal-on-metal total hip arthroplasties (MoM THAs). In total 155 THAs, in 35 male and 100 female patients (mean age 70.4 years, 42 to 91), underwent at least two MRI scans at a mean interval of 14.6 months (2.6 to 57.1), at a mean of 48.2 months (3.5 to 93.3) after primary hip surgery. Scans were graded using a modification of the Oxford classification. Progression of disease was defined as an increase in grade or a minimum 10% increase in fluid lesion volume at second scan. A total of 16 hips (30%) initially classified as 'normal' developed an abnormality on the second scan. Of those with 'isolated trochanteric fluid' 9 (47%) underwent disease progression, as did 7 (58%) of 'effusions'. A total of 54 (77%) of hips initially classified as showing adverse reactions to metal debris (ARMD) progressed, with higher rates of progression in higher grades. Disease progression was associated with high blood cobalt levels or an irregular pseudocapsule lining at the initial scan. There was no association with changes in functional scores. Adverse reactions to metal debris in MoM THAs may not be as benign as previous reports have suggested. Close radiological follow-up is recommended, particularly in high-risk groups.

Excision arthroplasty of superior tibiofibular joint for recurrent proximal tibiofibular cyst. A report of two cases.

Synovial cysts originating from proximal tibiofibular joint are commonly symptomatic. They can progress to cause pressure effects over the common peroneal nerve. In order to prevent recurrence the importance of excision of the ganglion and its stalk is emphasised. In recurrent cases treatment can be difficult. We describe an operation where after recurrence superior tibiofibular joint excision along with the cyst led to complete recovery in two cases.

A gas filled intradural cyst associated with disc degeneration.

A case of a lumbar intradural, extramedullary gas filled cyst is described. This was associated with degenerative disc disease and presented with radicular signs and symptoms. The radiological differential diagnosis of such a mass includes infection and tumours. The association of intradural gas with degenerative disc disease is previously reported. This case further illustrates the association of degenerative disc disease with an intradural gas filled cyst and provides an interesting radiological differential diagnosis for an extramedullary intradural mass.

Proton magnetic resonance spectroscopy ((1)H-MRS) of the brain following high-dose methotrexate treatment for childhood cancer.

BACKGROUND: To avoid the late sequelae associated with cranial radiation therapy in childhood, intermediate- or high-dose intravenous methotrexate (HDMTX) has found increasing application as a means of preventing the development of overt central nervous system disease in childhood acute leukaemia. However, acute and chronic neurotoxicity has been described following HDMTX therapy, and the long-term intellectual outcome in children treated in this way is inadequately documented. Proton magnetic resonance spectroscopy ((1)H-MRS) of the brain is a noninvasive, quantitative way of assessing aspects of cerebral metabolism, which has not previously been applied to the study of children undergoing central nervous system directed therapy. PROCEDURE: To evaluate the potential role of (1)H-MRS in the investigation of related neurotoxicity, 11 children who had received HDMTX (cumulative dose 6-96 g/m(2)) underwent localised (1)H-MRS, magnetic resonance imaging. Neuropsychological assessments were performed on the children who had more than 1 year of follow-up time since last methotrexate treatment. Control (1)H-MRS studies on 11 adult and 6 young volunteers were undertaken. Eight patients had spectra of adequate quality. Comparisons between (1)H-MRS metabolite ratios and normal controls were made. RESULTS: Patients had a low choline/water ratio compared to controls (P < 0.01). No differences between patient and control NAA/water, Cr/water, Naa/Cr, and Cho/Cr ratios were seen. Overall, 3 patients had abnormal white matter changes on MRI. The mean IQ of the patients (104.1) was in the normal range. CONCLUSIONS: It is postulated that choline depletion in the brains of these patients may reflect subclinical disturbances of myelin metabolism as a result of methotrexate therapy and may represent a possible avenue of treatment in patients with clinical chronic methotrexate-related neurotoxicity.

A retinacular sling for subluxing tendons of the first extensor compartment. A case report.

Over-zealous release of the first dorsal compartment of the wrist for de Quervain's disease or other lesions such as ganglia, may result in volar subluxation of the tendons of abductor pollicis longus and extensor pollicis brevis. This is usually asymptomatic, but may occasionally become disabling. We describe an operation using part of the extensor retinaculum to stabilise such a subluxation.

The Basingstoke Orthopaedic Database: a high quality accurate information system for audit.

The accuracy of a computerised audit system custom produced for the Orthopaedic Department has been validated by comparison with operating theatre records and patients' case notes. The study revealed only 2.5 per cent missed entries; of the recorded entries information regarding the nature of the operation was found to be 92.5 per cent complete and 98 per cent accurate. The high percentage accuracy reflects the high degree of medical input in operation of the system. The Basingstoke Orthopaedic Database is flexible, cheap and easy to maintain. Data is stored in a form that is readily applicable to standard software packages.

Mechanical properties of bone from iliac crest and relationship to L5 vertebral bone.

Apparent density, yield stress and yield energy were measured in transiliac cores of trabecular bone from iliac crest and craniocaudal cores of L5 vertebra from 26 cadavers. In the iliac crest, bone from the anterior superior spine region had significantly greater apparent density and had greater yield energy than bone from the center of the crest. Yield stress was greater at the anterior superior spine than either the center or at the posterior spine. Lumbar vertebral bone was uniform in its characteristics. Apparent density was the property showing the best correlation between iliac crest and L5 (r = 0.79), while yield energy was less well associated (r = 0.67). In L5, mechanical properties decline more rapidly with age than apparent density. Between the ages of 25 and 75 years the rate of fall of yield stress was twice and yield energy 2.6 times compared with the rate of fall of apparent density. Iliac crest behaved similarly. Yield stress in iliac crest paired for density in subjects less than 40 years and greater than 60 years was 40.7% lower in the older subjects (p = 0.03), suggesting a specific mechanical defect in old age. The yield stress advantage accruing to orientated lumbar bone was more marked at lower values of yield stress in the iliac crest when cores from the same cadaver were matched for apparent density. Mechanical properties of iliac crest bone are very dependent upon site and at no one site in the iliac crest do the physical properties satisfactorily predict those in the lumbar spine.

Renal trauma and the intravenous urogram.

A retrospective analysis of all patients with blunt abdominal trauma associated with haematuria admitted to one hospital (Royal United, Bath) in a 10-year period was conducted to establish the contribution of the intravenous urogram (IVU) in their management. Eighty-one case records were analysed. Of 35 IVUs performed in patients with microscopic (reagentstrip positive) haematuria, only one was abnormal. In contrast, 27 IVUs performed in patients with macroscopic (naked eye) haematuria revealed 17 major injuries and 5 previously unrecognized congenital abnormalities. It is concluded that an IVU is an unnecessary and non-contributory investigation in patients with microscopic haematuria and guidelines are suggested for the role of IVU in patients with blunt abdominal trauma associated with haematuria.

99mTc-MDP retention in osteoporosis: relationship to other indices of bone cell activity and response to calcium and vitamin D therapy.

Serum calcium, albumin, phosphorus, and alkaline phosphatase, urinary creatinine and retention of 99mTc-methylene bisphosphonate (99mTc-MDP) were measured in 61 subjects with osteoporosis and the values compared with those obtained in normal subjects. 99mTc-MDP retention was inversely related with urinary creatinine output in normal subjects. In osteoporotic subjects urinary creatinine output was lower and 99mTc-MDP retention higher even when urinary creatinine output was taken into account. Other measurements were similar. In 21 subjects these measurements together with urinary hydroxyproline were performed before and after treatment with calcium and vitamin D. 99mTc-MDP and alkaline phosphatase fell; urinary hydroxyproline was unchanged. A single 24 h urine measurement after 99mTc-MDP injection is a valuable method of predicting whether calcium and vitamin D therapy will be useful in a particular case of osteoporosis.