Table 2.
The number of graded discs at each lumbar disc level
| Grade I | Grade II | Grade III | Grade IV | Grade V | |
|---|---|---|---|---|---|
| L1–2 | 139 (92.1) | 12 (7.9) | – | – | – |
| L2–3 | 140 (92.7) | 3 (2.0) | 7 (4.6) | – | 1 (0.7) |
| L3–4 | 130 (86.0) | 9 (6.0) | 9 (6.0) | 3 (2.0) | – |
| L4–5* | 99 (65.6) | 16 (10.6) | 25 (16.6) | 11 (7.3) | – |
| L5–S1* | 111 (73.5) | 7 (4.6) | 15 (9.9) | 17 (11.3) | 1 (0.7) |
* Significantly higher grades of lumbar intervertebral disc degeneration compared to that at L1–2, L2–3, and L3–4 disc levels (p < 0.001 for all). A total of 755 lumbar intervertebral discs in 151 combat sports athletes were classified into 5 grades (Grade I–V), based on Pfirrmann’s classification (Pfirrmann et al. 2001). This system uses characteristics of a disc structure, a distinction between the nucleus and annulus, MRI signal intensity, and intervertebral disc height for grading. Grade I and II denote normal. Grade III–V reflects that degeneration exists in the disc. The percentages of each grade at the disc levels are given in parentheses