[MRI for diagnosis of low back pain: Usability, association with symptoms and influence on treatment]

Abstract

Background: Non-specific low-back pain is a worldwide problem. More specific diagnosis could improve prognosis. Magnetic resonance imaging (MRI) became available in Akureyri Hospital in 2004 but its utilisation in diagnosing low-back pain has not been investigated.

Objective: To study the use of MRI in diagnosing low-back pain, correlation of the MRI outcomes with other clinical findings and its possible effects on treatment.

Methods: Retrospective, descriptive analysis of patients' journals. Included were all adult (18 years and older) residents of Akureyri who underwent low-back MRI in Akureyri Hospital in 2009.

Results: During 2009, 159 patients (82 women) underwent low-back MRI, mean age 51 years (18-88). The most common pathological findings were connected to the lumbar disk. Disk herniation was diagnosed in 38% of the patients, 77% at the L4-L5 or L5-S1 level. MRI results correlated poorly with symptoms and clinical findings. Treatment options for disk herniation were prescription of medications (70%), referrals to physiotherapy (67%) and orthopaedic surgeons (61%). Nine patients were operated. Among patients referred to physiotherapy, 49% were first examined with MRI and thus waited longer for referral than those referred directly to physiotherapy (p=0.008). One year after the MRI, recovery rate was 51%. Prognosis was better for patients referred to physiotherapy (p=0.024).

Conclusions: MRI seems to be used for general diagnosis of low-back pain. Symptoms and MRI results correlate poorly, emphasizing the need for the doctor´s thorough weighing of clinical and MRI findings when diagnosing low-back pain. Recovery rate of patients with lumbar disk herniation improves by physiotherapy. The general use of MRI might delay treatment. Key words: Magnetic resonance imaging, clinical diagnosis, low-back pain, lumbar disk herniation, treatment, physiotherapy. Correspondence: Gunnar Svanbergsson gsvanbergs@gmail.com.