Table 2. Indices of bone quality and muscle density, CSA, and function in participants with chronic SCI grouped by sex and impairment severity (n = 65a).
| Anatomic site |
Variable (units) |
All participants with chronic SCI (n = 65a) |
Male participants with chronic SCI (n = 45) |
Female participants with chronic SCI (n = 20) |
Participants with AIS A/B (n = 40) |
Participants with AIS C/D (n = 25) |
| 4% tibia | Trabecular vBMD (mg/cm3) | 130.1 (54.5) | 137.2 (55.3) | 114.1 (50.3) | 101.0 (38.7) | 176.7 (42.6)d |
| 66% tibia | Cortical vBMD (mg/cm3) | 1,082.1 (51.8) | 1,179.8 (53.7) | 1,137.6 (66.4)c | 1,139.1 (73.0) | 1,168.8 (46.7) |
| Cortical thickness (mm) | 3.21 (0.94) | 3.37 (0.95) | 2.84 (0.83)c | 2.84 (0.92) | 3.80 (0.65)d | |
| Cortical CSA (mm2) | 256.0 (76.7) | 278.8 (74.9) | 204.7 (53.4)c | 228.5 (67.5) | 300.0 (70.8)d | |
| PMI (mm4) | 45,304 (18,602) | 52,188 (17,505) | 29,816 (9,551)c | 40,867 (15,750) | 52,404 (20,840)d | |
| Muscle density (mg/cm3) | 53.5 (13.3) | 54.2 (13.6) | 51.9 (12.7) | 49.4 (13.8) | 60.2 (9.3)d | |
| Muscle CSAb (cm2m) | 19.9 (8.7) | 22.1 (8.7) | 14.9 (6.5)c | 16.3 (6.8) | 25.7 (8.3)d | |
| cLEMS | 2.8 (4.7) | 3.09 (4.97) | 2.05 (4.20) | 0 (0) | 7.2 (5.2)d |
Note: Values given as mean (SD). SCI = spinal cord injury; AIS = American Spinal Injury Association Impairment Scale; cLEMS = calf lower extremity motor score; CSA = cross-sectional area; pQCT = peripheral quantitative computed tomography; SD = standard deviation; vBMD = volumetric bone mineral density.
a
Five participants did not complete pQCT scans.
b
Muscle CSA (cm2) was multiplied by tibia length (m).
c
Significant difference between male and female participants (P < .05).
d
Significant difference between AIS A/B and AIS C/D groups (P < .05).