An MRI study of 162 patients with lower back pain (LBP) and/or leg pain (LP) measured and analyzed the thickness of the ligamentum flavum (LF) at different levels of the lumbar spine and concluded that, though the LF thickness increased with the age of the patient, there was no apparent correlation between a decrease in disc-height and LF thickness. In fact, researchers found that LF thickness had already begun to increase in patients under 40, refuting the theory that LF thickness was caused by buckling of the LF into the spinal canal due to age-related degeneration.

The Study

The researchers involved in this study wanted to examine the theory that hypertrophy of the LF—which covers the postural-lateral spinal canal—is caused by age-related degeneration. Subjects included 87 female and 75 male LBP patients whose mean age was roughly 52-years-old. Patients with scoliosis, spinal fracture, or other deformities of the spine were excluded from the study. Radiographs were conducted, and the thickness of 648 LF was measured at various levels of the lumbar spine, and an analysis was performed by the researchers using Pearson’s coefficient test.

Results

Three important findings were achieved during analysis of the MRI results in this study: LF thickness increases with age; this thickness is not as pronounced at the L2-3 and L5-S levels as in other levels; the LF thickness was extremely pronounced at the L4-5 levels, particularly in younger subjects. Researchers concluded that LF thickening was already in progress in the back-pain study patients between the ages of 30-39.

The results of this study indicate that practitioners should pay close attention to posterior, as well as anterior, elements of disc herniation patients prior to planning for surgical procedures. Thickening of the LF in LBP patients is more likely to occur prior to the age of 40 and is not caused by disc degeneration and LF buckling into the spinal canal, as has been previously suggested. Patients with obvious thickness of the LF at L2-3 should be examined for lumbar spinal canal stenosis, as the results of the study indicate a correlation between the two conditions.

Blurb: A study of lower back pain patients measured and analyzed ligamentum flavum (LF) at different levels of the lumbar spine and concluded that LF thickening occurs in younger (30-40) LBP patients and is not caused by buckling of the LF into the spinal canal due to age-related degeneration.