Summary. 162 patient cohort with serial Metal Artefact Reduction Sequence MRI scans. Patients with normal initial scans can be followed up at 1 year. Those with abnormal scans should be followed up at a shorter interval of 6 months. Introduction. Cross-sectional imaging is a key investigation in the assessment and surveillance of patients with metal-on-metal (MoM) hip arthroplasty. We present our experience of Metal Artefact Reduction Sequence (MARS) MRI scanning in metal on metal hip arthroplasty. We aimed to investigate the natural history and radiological disease progression from Adverse Reactions to Metallic Debris. Methods. A total cohort of 626 patients who had metal on metal arthroplasty underwent MARS MRI scanning with 162 patients having more than one MRI scan. A musculoskeletal radiologist reviewed and reported on all MRI scans. The findings were described as either normal or classified according to Hart et al. We then considered the patient's progression between groups on serial scans and the time intervals between them. Results. 65 patients had a normal first MRI, 38 (54%) remained normal on follow-up scan with a mean scanning interval of 14.6 months. The remaining 27 patients who progressed form normal to either Type 1/2/3 did so over a mean scan interval of 14 months. Of those 56 patients with a Type 1 (thin walled fluid collection) 28.5% of these progressed during interval scanning and 8.9% of Type 1 reactions returned to normal. Over half the patients with an abnormal initial MARS MRI scan 46/85 (54%), with either Type 1 or 2 abnormal soft tissue reaction, had progressed to more severe types following a mean interval scan time of 12.2 months. Discussion. A safe interval for a follow-up MARS MRI scanning in a patient who has normal initial findings appears to be 12 months. We consider a 6-month scan appropriate for patients under surveillance who have initial abnormal cross-sectional imaging

Background and purpose. There is on-going debate about a possible link between manipulation and stroke in patients, and a growing interest in other treatment reactions such as increased pain. Evidence about manipulation is contradictory. There is little published information about outcomes in osteopathy. We aimed to address this gap. Methods and results. A survey was sent to all UK practising osteopaths. Another survey was sent to patients recruited by osteopaths. Patients were surveyed before treatment, one day and two days after treatment and at six weeks. 1,082 (27.8%) osteopaths completed the practitioner survey. 2,057 patients, recruited from 212 osteopaths, completed questionnaires before, and directly after their treatment. 1,387 patients provided data six weeks after treatment. Between 10% and 20% of patients experienced increased symptoms/pain related to their main complaint in the days directly following treatment. This was highest for new patients. At 6 weeks, 4% of patients reported temporary disability, which they attributed to osteopathic treatment. 10% of patients reported seeking further consultation for worsening symptoms associated with osteopathic care. The comparison between those that received manipulation and those that did not suggests that manipulation was not linked to worsening outcomes. In the preceding year, 4% of osteopaths reported that they had patients who experienced a range of serious events. The most common event described was the occurrence of peripheral neurological symptoms. There were also 7 reports of stroke-like symptoms. Conclusion. Serious adverse events are rare. Transient increase in intensity of pain/symptoms is common. Conflict of interest: S Vogel, T Mars and R Froud are osteopaths. S Vogel, and T Pincus have received payment for keynote presentations by the General Osteopathic Council. M Underwood has received payment for the delivery of a keynote presentation by the British Osteopathic Association. Sources of funding: The majority of funding was provided by the General Osteopathic Council. Some additional funding was provided by the British School of Osteopathy

Metal-on-metal (MOM) hip arthroplasty, including resurfacing, has become the subject of recent research and debate. There is the perceived benefit of improved wear rates of bearing surfaces leading to superior durability and performance of these types of implant. An associated feature of MOM bearing surfaces is the generation of metal ions. These can have local and systemic cytotoxic effects. An immunoloigical response has been suggested, however, metal wear debris may cause direct damage to cellular DNA. Studies have shown that release of these ions is related to bearing diameter and component alignment. However, little is known about the relationship between metal ion levels and implant survivorship. The MHRA has published guidelines on the follow-up of patients with MOM implants including measurement of serum ion levels and cross sectional imaging. Between February 2001 and November 2009, 135 patients (164 hips) had MOM resurfacing arthroplasty at our institution. We report a retrospective analysis of the data generated by review of these patients. Of the 135 patients, 91 were identified for clinical review. Each patient had serum metal ion levels measured, plain AP radiographs of the pelvis examined and, in the presence of raised metal ions, a Metal Artefact Reduction Sequence (MARS) MRI performed. 27 patients (35 hips) had raised metal ion levels (Cobalt and Chromium). Patients with raised metal ion levels had a mean acetabular cup inclination of 52.7 degrees compared with a mean inclination of 48.6 degrees in patients with normal ion levels (p<0.05). MARS MRI in the raised ion group revealed 9 patients with appearances suggestive of ALVAL. A number of these patients had hip revision surgery with the remainder awaiting potential revision. These findings reflect current evidence suggesting a relationship between sub-optimal component position and raised metal ion levels and an increased rate of ALVAL