Occult hip fractures : using MRI in diagnosis and patient management

Approximately 75,000 hip fractures occur in the UK annually and most are diagnosed using conventional radiography. However 10% of fractures are missed and a delay in establishing the injury often results in more complex treatment and a worse prognosis. Hip fractures have a mortality rate of 20-25% which increases as treatment is delayed. The key goal of enabling the patient to return to their previous level of functioning is improved by performing hip surgery within 24 hours of injury. Systematic review aimed to consider the role of MRI in detecting hip fractures relative to other modalities, the most appropriate scan sequences, and operational logistics. Results indicate that coronal T1 weighted MRI has a sensitivity of 100%, justifying the use of emergency scan slots. It is important to screen the patient for MRI contraindications early in the diagnostic process in order to optimise time. Unlike CT, MRI has no radiation dose. Radio-nuclide imaging is unlikely to be possible within the 24 hour time window due the delivery limitation of radio-isotope. NICE guidelines now recommend the use of MRI to aid diagnosis of an occult hip fracture in cases where conventional imaging is negative but the patient symptoms suggest otherwise, due to its higher sensitivity.