Unintended Consequences: An Evaluation Quantifying Benefits, Iatrogenic Harms and Downstream Cascade Costs of Musculoskeletal Magnetic Resonance Imaging (MRI) in UK Primary Care

Abstract

Objectives: The largest proportion of GP magnetic resonance imaging (MRI) is musculoskeletal, with consistent annual growth. There is lacking supporting evidence, with potential harms from early imaging overuse. We evaluated practice to improve pathways and patient safety. Methods: Cohort evaluation of routinely collected diagnostic and general practice data across a UK metropolitan primary care population. We reviewed patient characteristics, results and healthcare utilisation. Results: Of 306 MRIs requested by 107 clinicians across 29 practices, only 4.9% (95% CI ±2.4%) appeared indicated and only 16.0% (95% CI ±4.1%) received appropriate prior therapy. 37.0% (95% CI ±5.5%) documented patient imaging request. Most had chronic symptoms and half had psychosocial flags. Mental health was addressed in only 11.8% (95% CI ±6.3%) of chronic sufferers with psychiatric illness. 1.3% (95% CI ±1.3%) of results revealed diagnoses relevant to change management (therapeutic-yield). Only 7.8% (95% CI ±3.0%) were appropriately managed without additional referral. 16.7% (95% CI ±4.2%) of results appeared correctly interpreted by GPs, with erroneous over-perception of surgical targets in 65.4% (95% CI ±5.3%) who suffered low-value post-MRI referral cascades due to misdiagnosis and overdiagnosis. 20-30% of GP specialist referrals convert to a procedure, whilst MRI-triggered specialist referrals showed near-zero conversion-rate. Imaged patients experienced considerable delay to appropriate care. Cascade costs exceeded direct-MRI costs and GP-MSK-MRI potentially more than doubles expenditure, compared with physiotherapist-lead assessment services, for little-to-no added therapeutic-yield, unjustifiable by cost-consequence or cost-utility analysis. Conclusion: Unfettered GP-MRI access demonstrates disutility and considerable avoidable patient harm through salient misinterpretation and ubiquitous low-value referral cascades. Only 1-2 patients need to be imaged for one to suffer mismanagement. Direct-access imaging is neither clinically, nor cost-effective and de-implementation could be considered in this setting. GP-MSK-MRI fuels unnecessary healthcare utilisation and nocebic patient beliefs, whilst appropriate care and psychosocial barriers to recovery appear neglected.