Although retrolisthesis is not a well-known condition by many medical specialists dealing with back problems and it has been regarded as a radiological incidental finding with no clinical significance, a growing prove is now evolving stating that retrolisthesis could be a cause of many backache complaints and a sequelae of an altered spine biomechanics.
Objectives: to study and analyze the various biomechanical characteristics of retrolisthesis and its relationship with various radiological parameters of the lumbar spine and other patient’s factors. Patients and Method: Forty patients, twenty six males, and fourteen females with an age range from 40–66 years with radiological evidence of significant lumbar spine retrolisthesis (slip > 3 millimeters) were evaluated clinically and radiologically by plain radiography and MRI in Basra General Hospital and Ibn AL-Bittar Private Hospital, during the period from the 1st of August 2014 to the 1st of March 2015. After a thorough history and physical examination, various radiological parameters were obtained including the lumbar lordosis, sacral slop, pelvic incidence, pelvic tilt, all those measurements were done digitally. A statistical analysis was made via IBM SPSS ver.17 and the results were compared with that of similar studies. Results: The retrolisthesis was found to be more common with more slip distance in males than in females, males=26 (65%), females=14 (35%), P-value=0.026, the mean of slip in mm in males was (4.002) and in females was (3.71). The patients had a mean BMI equal to (26.025= overweight). The most common level at which retrolisthesis occur in this study was the L5-S1 (40%) then L4-L5 (22.5%).
All the radiological parameters (the lumbar lordosis, sacral slop, pelvic incidence, and pelvic tilt) were lower than the known normal values in healthy subjects. Conclusion: It seems that retrolisthesis is not just an incidental finding, it may be a kind of a compensatory reaction for an abnormal spine biomechanics. The males are affected more frequently than females with a more slip distance.
The L5-S1 followed by the L4-L5 are the most common sites in both sexes. The degenerative spinal disease is the main cause of retrolisthesis in all patient’s groups regardless of sex or age.