Mirels’ score predicts the likelihood of sustaining pathological fractures using pain, lesion site, size and morphology. The aim is to investigate its reproducibility, reliability and accuracy in upper limb bony metastases and validate its use in pathological fracture prediction.

A retrospective cohort study of patients with upper limb metastases, referred to an Orthopaedic Trauma Centre (2013–18). Mirels’ was calculated in 32 patients; plain radiographs at presentation scored by 6 raters. Radiological aspects were scored twice by each rater, 2-weeks apart. Inter- and intra-observer reliability were calculated (Fleiss’ kappa test). Bland-Altman plots compared variances of individual score components &total Mirels’ score.

Mirels’ score of ≥9 did not accurately predict lesions that would fracture (11% 5/46 vs 65.2% Mirels’ score ≤8, p<0.0001). Sensitivity was 14.3% &specificity was 72.7%. When Mirels’ cut-off was lowered to ≥7, patients were more likely to fracture (48% 22/46 versus 28% 13/46, p=0.045). Sensitivity rose to 62.9%, specificity fell to 54.6%. Kappa values for interobserver variability were 0.358 (fair, 0.288–0.429) for lesion size, 0.107 (poor, 0.02–0.193) for radiological appearance and 0.274 (fair, 0.229–0.318) for total Mirels’ score. Values for intraobserver variability were 0.716 (good, 95% CI 0.432–0.999) for lesion size, 0.427 (moderate, 95% CI 0.195–0.768) for radiological appearance and 0.580 (moderate, 0.395–0.765) for total Mirels’ score.

We showed moderate to substantial agreement between &within raters using Mirels’ score on upper limb radiographs. Mirels’ has poor sensitivity &specificity predicting upper limb fractures - we recommend the cut-off score for prophylactic surgery should be lower than for lower limb lesions.

The arrival of major trauma centres (MTC) to Scotland highlights the need for structured management of polytrauma patients. The aim was to report the epidemiological profile of polytrauma patients (Injury Severity Score (ISS) 15) admitted to a large trauma unit in the UK and gather information about the initial management of this severely injured cohort.

Prospectively collected data from the Scottish Trauma Audit Group (STAG) database of 366 polytrauma patients (ISS <15 & aged ≥13 years) admitted to a single trauma unit, from 1st January 2013 to 31st October 2017 was analysed. Data included patient demographics, injury characteristics, length of stay (LOS) and survivorship.

The median age was 49 years (range 13–93) and females made up 31.1% of the population. There was a mean ISS of 25.7 (range 15–75) and mean LOS of 19 days. The overall mortality rate was 21%. Higher mortality occurred among females (p<0.001), patients ≥60 years age (p<0.001), patients who sustained their injury at home (p<0.0001), and those with head injuries (p<0.01). Orthopaedic injuries were present in 187 patients (51.1%) with a mortality rate of 10.7%. The most common mechanism of injury was road traffic collision (41.5%) and these patients had a significantly higher ISS (p<0.01). A fall from height <2m was associated with higher mortality (p=0.01).

This study is the largest of its kind and presents a detailed epidemiological profile of patients attending a large UK trauma unit. This knowledge will help guide initial management and aid in resource and capacity planning for the future.