Alistair J. Stirling

Association between sciatica and Propionibacterium acnes

We hypothesised that the inflammation seen around the nerve root in patients with sciatica may be caused by microbial infection. We used a newly developed serological test to diagnose deep-seated infections caused by low virulent gram-positive microorganisms. 43 of 140 (31%) patients with sciatica tested positive. Intervertebral disc material from a further 36 patients with severe sciatica who had undergone microdiscectomy was cultured for the presence of microorganisms. 19 of these patients (53%) had positive cultures after long-term incubation. Propionibacterium acnes was isolated from 16 of the 19 (84%) positive samples. Low virulent microorganisms, in particular P acnes, might be causing a chronic low-grade infection in the lower intervertebral discs of patients with severe sciatica. These microorganisms could have gained access to the spinal disc after previous minor trauma.

Analysis of clinical isolates of Propionibacterium acnes by optimised RAPD

Random amplification of polymorphic DNA (RAPD) was evaluated as a genotypic method for typing clinical strains of Propionibacterium acnes. RAPD can suffer from problems of reproducibility if parameters are not standardised. In this study the reaction conditions were optimised by adjusting template DNA concentration and buffer constituents. All isolates were typeable using the optimised RAPD protocol which was found to be highly discriminatory (Simpsons diversity index, 0.98) and reproducible. Typing of P. acnes by optimised RAPD is an invaluable tool for the epidemiological investigation of P. acnes for which no other widely accepted method currently exists.

A simplified Galveston technique for the stabilisation of pathological fractures of the sacrum.

Abstract Mechanical stabilisation of pathological fractures of the sacrum is technically challenging. There is often inadequate purchase in the sacrum, and stabilisation has to be achieved between the lumbar vertebrae and ilium. We present a simplification of the Galveston technique. We treated a total of six patients with this technique, four for metastatic disease and two for primary tumours. Our technique consists of the formation of a proximal stable construct using ISOLA pedicle screws linked distally using a modular system of connectors to threaded iliac bolts with cross linkages. Neurological decompression and fusion was performed as appropriate. The benefits of this method are: ease of access to the ilium, a solid purchase to the ilium, less rod contouring and shorter operating time. We have had no operative complications from this procedure. All patients were discharged home mobile, with a reduced opiate requirement.

Thoracic spinal cord compression caused by hypopbosphataemic rickets: a case report and review of the world literature

Vitamin D resistant hypophosphataemic rickets is a rare cause of spinal cord compression. The compression is caused by a combination of thickening of the laminae and calcification of the ligamentum flavum. Modern imaging techniques including CT and MRI provide excellent detail of both the level and degree of compression. MRI is particularly useful for examining the rest of the spinal cord for areas of impending compression and for postoperative follow-up. With careful surgical decompression a full neurological recovery can be achieved.

Optimizing the management of patients with spinal myeloma disease

Myeloma is one of the most common malignancies that results in osteolytic lesions of the spine. Complications, including pathological fractures of the vertebrae and spinal cord compression, may cause severe pain, deformity and neurological sequelae. They may also have significant consequences for quality of life and prognosis for patients. For patients with known or newly diagnosed myeloma presenting with persistent back or radicular pain/weakness, early diagnosis of spinal myeloma disease is therefore essential to treat and prevent further deterioration. Magnetic resonance imaging is the initial imaging modality of choice for the evaluation of spinal disease. Treatment of the underlying malignancy with systemic chemotherapy together with supportive bisphosphonate treatment reduces further vertebral damage. Additional interventions such as cement augmentation, radiotherapy, or surgery are often necessary to prevent, treat and control spinal complications. However, optimal management is dependent on the individual nature of the spinal involvement and requires careful assessment and appropriate intervention throughout. This article reviews the treatment and management options for spinal myeloma disease and highlights the value of defined pathways to enable the proper management of patients affected by it.

A 45-year-old woman with a pre-sacral mass lesion: diagnosis and discussion

The MR examination demonstrates a 6×2.5-cm pre-sacral mass lesion that is extending into and expanding the left S1 exit foramen. This mass extends into the epidural fat, displacing and partially surrounding the S1 nerve, but it did not extend distally to affect the exiting S2 or S3 nerves. The lesion shows a heterogeneous signal pattern on T1and T2weighted sequences with focal areas of high signal intensity on the T1-weighted sequences indicative of small areas of haemorrhage. The lesion is predominantly hyperintense to muscle on T2 weighting and following contrast medium administration, and a relatively uniform enhancement pattern is identified. Trans-sacral biopsy by an approach lateral to the exit foramen was performed to exclude recurrent rectal carcinoma. The biopsy material demonstrated endometriosis characterised by endometrial glands surrounded by endometrial stroma with strong positivity for oestrogen and progesterone. As a result, the patient was commenced on hormonal treatment and the neurological symptoms improved. Although endometriosis is a common condition affecting women of reproductive age, it may rarely affect both the central and peripheral nervous systems. The exact prevalence is unknown, but a greater number of cases affecting the peripheral nervous system have been reported, the commonest being the sciatic nerve [1]. Presentation is typically with cyclical pain in a sciatic distribution with sensory loss in the S1 dermatome and motor weakness. Symptoms may result from either direct compression or fibrosis of the nerve. The symptoms are usually progressive unless treated and prolonged compression can lead to irreversible damage. A number of theories have been postulated to explain the extra-uterine spread of endometriosis [2]. In the ovary, the commonest site of endometriosis outside of the uterus, lymphatic drainage from the uterus has been suggested to be the cause [3]. Distant sites of extra-pelvic endometriosis, such as the thorax or central nervous system, have been attributed to haematological transport, but coeloemic tissue metaplasia has also been postulated, as endometriosis can occur in patients who have never menstruated or even in post-menopausal women [4]. This has been refuted by other workers who have found asymmetric sciatic nerve endometriosis and diaphragmatic disease more commonly on the right side, supporting the menstrual reflux theory because of the transport of endometrial cells in the cycle of peritoneal fluid redistribution [5]. In the pelvis, the left The case presentation can be found at doi:10.1007/s00256-009-0831-6 I. Nagra : S. L. J. James (*) Department of Radiology, The Royal Orthopaedic Hospital NHS Foundation Trust, Birmingham B31 2AP, UK e-mail: steven.james@roh.nhs.uk

A 45-year-old woman with a pre-sacral mass lesion

A 45-year-old woman presented with a 3-year history of intermittent episodes of low back pain associated with leftsided sciatica. This had progressed over the past 18 months and the pain was now radiating to her toes, causing difficulty with walking. Clinical examination was normal and initial investigations including routine blood tests and radiographs of the lumbosacral spine were unremarkable. Her past medical history included rectal carcinoma, previous hysterectomy and bilateral oophorectomy, asthma and hyperthyroidism. MRI of the lumbar spine (not shown) and sacrum was performed including sagittal T1-weighted (Fig. 1a), sagittal T2-weighted (Fig. 1b), axial T2-weighted (Fig. 1c), axial fat-suppressed T1-weighted images preand post-gadolinium administration (Fig. 1d, e). A trans-sacral CT-guided biopsy was performed, the histology of which is illustrated in Fig. 2.