Clinical and Magnetic Resonance Imaging Factors Which May Predict the Need for Surgery in Lumbar Disc Herniation

STUDY DESIGN: Case-control. PURPOSE: Evaluate clinical and imaging factors which may predict the risk of failure of medical therapy in patients with lumbar disc herniation (LDH). OVERVIEW OF LITERATURE: LDH is a common cause of low back pain and radicular leg pain, with a generally favorable natural course. At present, however, it is not possible to identify patients who may be candidates for surgery in an early stage of their disease by means of clinical signs or diagnostic imaging criteria. METHODS: We designed a study investigating patients with untreated low back pain to assess the predictive value of demographic, clinical or imaging findings in identifying patients who finally would meet the classic current criteria for surgery. RESULTS: Among 134 patients, 80.6% were successfully treated with conservative therapy and 19.4% finally underwent surgery. Sex, occupation, involved root level, presence of Modic changes, osteophytes or annular tears were not significantly different between the 2 groups, while cerebrospinal fluid block, Pfirrmann's grade, location of herniation with regard to the midline, and type of herniation were significantly different. Anteroposterior fragment size was significantly higher and intervertebral foramen height and thecal sac diameters were significantly lower in the surgical group. CONCLUSIONS: Although it is strongly recommended to practice conservative management at first for patients with LDH symptoms, the results of this study shows that higher Pfirrmann's grade, more laterally located discs, extrusion and protrusion herniation types, and larger fragments could predict the risk of conservative treatment failure. This way, unnecessarily prolonged conservative management (beyond 4-8 weeks) may be precluded.