Establishing local diagnostic reference levels for common orthopaedic procedures using the mini C-arm fluoroscope.

OBJECTIVE: Mini C-arm fluoroscopes are widely used by orthopaedic surgeons for intraoperative image guidance without the need for radiographers. This puts the responsibility for radiation exposure firmly with the operating surgeon. In order to maintain safe and best practice under U.K. Ionising Radiation (Medical Exposure) Regulations, one must limit radiation exposure and audit performance using national diagnostic reference levels (DRLs). In the case of the mini C-arm, there are no national DRLs. IR(ME)R, therefore, require the establishment of local DRLs by each hospital to act as an alternative guideline for safe radiation use. The aim of our audit was to establish local DRLs based on our experience operating with the use of the mini C-arm over the last 7 years. METHODS: This retrospective audit evaluates the end dose-area product (DAP) recorded for common trauma and orthopaedic procedures using the mini C-arm in a busy district general hospital.We present the quartile data and have set the cut-off point as the third quartile for formulating the local DRLs, consistent with the methodology for the conventional fluoroscope. RESULTS: For our data set (n = 1664), the third quartile DAP values were lowest for surgeries to the forearm (5.38 cGycm2), hand (7.62 cGycm2), and foot/ankle (8.56 cGycm2), and highest for wrist (10.64 cGycm2) and elbow (14.61 cGycm2) procedures. ADVANCES IN KNOWLEDGE: To our knowledge, this is the largest data set used to establish local DRLs. Other centres may find our guidelines useful whilst they establish their own local DRLs.

Failure of the Femoral Component in a Cemented Total Knee Replacement: A Case Report.

CASE: The usual mechanism of failure of a total knee arthroplasty is aseptic loosening of the tibial component. We present a case of an atraumatic late failure by fracture of the femoral component in an active 83-year-old and review the very small number of similar cases within the literature. CONCLUSION: Although it is difficult to draw firm conclusions on such a rare presentation, it appears the heavy-set, active man may be at risk of a femoral component fracture in the long-term. This case also raises an important question about diligence in cementing techniques for the femoral component.

Cement Pedestal Spacer Technique for Infected Two-stage Revision Knee Arthroplasty: Description and Comparison of Complications.

BACKGROUND: Infection following total knee arthroplasty (TKA) is a significant complication, with an incidence of up to 2% in primary TKA and 4%-8% in revision cases. Two-stage revision is the gold standard treatment for long-lasting infections of TKA. The purpose of this study was to describe the cement pedestal spacer technique used in infected two-stage revision knee arthroplasty and compare complications against conventional fixed and mobile cement spacers. PATIENTS AND METHODS: A retrospective review was conducted in all cases who underwent two-stage TKA revision for infection between 2009 and 2015. These cases were separated into groups depending on the cement spacer utilized (fixed, mobile nonpedestal, and mobile spacers with cement pedestal). The cement pedestal technique involves press fitting a cement cylinder into the femur before definitive spacer insertion. RESULTS: Forty four patients underwent two-stage revision TKA. Fewest complications were observed in the pedestal group, with no spacers having subluxed/tilted. The longest followup was also observed in the pedestal group (mean 52.5 months). Mobile spacers with no cement pedestal displayed the highest reinfection rate (16.7%) and the greatest number of cases with complications (malalignment, subluxation, tilting, and spacer fracture). All patients in the pedestal group were ambulatory after the first-stage revision. CONCLUSIONS: The cement pedestal technique minimizes complications by optimizing component positioning and balancing. It also safely extends the indication for an articulated spacer into a set of cases with more extensive bone loss and allows for extended monitoring of inflammatory markers.

Paediatric supracondylar humerus fractures.

This article gives a practical guide to the management of supracondylar fractures of the humerus in paediatric patients, from initial presentation to definitive treatment. It reviews the optimal management of this common and serious injury based on current evidence including the British Orthopaedic Association Standards for Trauma (BOAST) 11 standard.

Eye injuries in the extreme environment ultra-marathon runner.

We present the case of an ultra-marathon runner who developed a painful irritated eye due to prolonged exposure to high wind speed and sub-zero temperatures causing transient freezing and subsequent abrasion of the cornea. We recommend that all ultra-marathon runners racing in windy or exposed conditions should wear wrap-around eye protection or goggles. If runners present to checkpoints or after the race to primary care or the emergency department with ocular pain, corneal freezing and abrasions should be considered. Management should include ocular examination and withdrawing the runner from harmful conditions.

Two further investigations of autobiographical memory in semantic dementia.

A number of investigations in semantic dementia have documented better retrieval of recent personal events compared to those in the more distant past (Graham and Hodges, 1997). Westmacott et al. (2001) challenged this result, however, finding relative preservation of remote memories in a single case of semantic dementia when he was tested using family photographs. In Experiment 1, we tested two possible explanations for the discrepancy between the published papers: (a) that there is a significant effect of modality in autobiographical retrieval in semantic dementia (e.g., patients will show better, or even preserved, remote memory when tested on nonverbal, compared to verbal, tasks); and (b) that the distinct pattern seen between patients is attributable to the different methods adopted for scoring the episodic quality of the memories. A patient with semantic dementia, AM, produced autobiographical memories to both words and family photographs. These personal events were scored by two raters using the scoring method described by Westmacott et al. (2001) and that reported by Graham and Hodges (1997). It was found that AM showed similar levels of remote memory impairment regardless of whether the cue was verbal or nonverbal. In addition, significant effects of time were revealed in AM's performance on the verbal memory test, regardless of which method was used to score the memories. In Experiment 2, we investigated a related question: whether the relatively better retrieval of memories in semantic dementia could be due to over rehearsal of highly salient recent experiences? Four patients were tested on their ability to remember a recent event (either a trip to London or events from a Formula One Grand Prix race) using specially designed autobiographical questionnaires. It was found that all four were able to perform this task, although one patient showed evidence of some forgetting over three months, and another exhibited difficulty discriminating between two similar events. Together, the two experiments further confirm that patients with semantic dementia show a modality independent autobiographical memory deficit, with better retrieval of recent events.