The role of lumbar spine x-rays in the diagnosis and management of patients who present with low back pain
Background: Low back pain is a common condition and affects most people at least once in their lives. The causes of low back pain (LBP) are numerous and may include non-specific mechanical causes, or specific causes which may be of a more serious nature. Researchers have tried to link specific history and physical examination findings with certain disorders, but as of yet, have been unsuccessful. Research has shown that x-rays may be over utilized and the guidelines for referral are not always adhered to. Furthermore, there is a paucity of literature on the role of x-rays in influencing the management of patients with low back pain. Objectives: The objectives of this retrospective study were: 1) to determine the relationship between the clinical and the radiographic diagnoses of patients with LBP, 2) to record the consultation at which a lumbar spine x-ray was requested by the student or clinician and the reasons thereof, 3) to record the suspected clinical diagnoses and management of the selected patients prior to referral for lumbar spine x-rays, 4) to determine the number of incidental radiographic findings in the selected patients’ x-rays, and 5) to determine any change in the clinical diagnoses and management following radiographic reporting of the selected patients’ x-rays. Method: The Chiropractic Day Clinic (CDC) at the Durban University of Technology (DUT) archives were searched for lumbar spine radiographs and the corresponding patient files of patients who presented with LBP from 1 January 1997 to 31 July 2010. Data collection was in a stepwise process with the anteroposterior and lateral lumbar spine x-rays being read first, without any knowledge of the patient’s main complaint and then the corresponding patient files were evaluated and selected clinical variables were recorded. Statistical analysis included the use of frequency counts, percentages, mean, standard deviation and range for the descriptive objectives. Diagnoses were categorized into specific groups and indicator variables were used to construct two-by-two tables of absence or presence of radiographic vs. clinical diagnosis for each specific diagnosis to determine any possible associations. Results: The mean age of the patients was 43.9 (± 16.9) years and the number of male and female patients were 40 and 34 respectively. It was not possible to correlate the clinical and radiographic diagnoses because the categories were too different for any statistical test to be performed. Spondylosis was the most common radiographic finding. The majority of the lumbar spine x-rays were requested at the first consultation. No suitable reason for obtaining the x-ray was provided in 14.6% of the x-rays requested and 20.7% were requested to examine for an unspecified pathology. Of the 74 patients in this study, 44 patients did not have a change in diagnosis, which means that 59.5% of the diagnoses stayed the same after x-ray examination. However, in 30 (40.5%) of cases the clinical diagnosis was changed following x-ray examination. This may indicate an overuse of x-rays at the CDC. Most patients were diagnosed with the non specific mechanical causes of low back pain. A wide range of treatment modalities were utilized both before and after x-rays were taken, including soft tissue therapies, electrotherapies and spinal manipulation. Following x-ray imaging there was a greater use of spinal manipulation ie. 62% versus only 39% of cases prior to imaging. Conclusion: Lumbar spine x-rays may be over utilised at the CDC but their findings were influential in the diagnosis and management in 30 (40.5%) of the patients. The majority of the clinical diagnoses were of the mechanical or non-specific causes of low back pain.