Table 3.
Patients' Demographics for Each Disease
| Factor | OLF | OPLL | OPLL + OLF | IET | IMSCT | VT | SCH | VF | TDH |
| n | 48 | 30 | 27 | 98 | 64 | 17 | 7 | 4 | 5 |
| Sex | |||||||||
| Male | 35 (72.9%) | 17 (56.7%) | 14 (51.9%) | 51 (52.0%) | 36 (56.3%) | 9 (52.9%) | 2 (28.6%) | 1 (25.0%) | 2 (40.0%) |
| Female | 13 (27.1%) | 13 (43.3%) | 13 (48.1%) | 47 (48.0%) | 28 (43.8%) | 8 (47.1%) | 5 (71.4%) | 3 (75.0%) | 3 (60.0%) |
| Mean age (years) | 56.5 ± 15.6 yr | 52.3 ± 14.8 yr | 52.8 ± 10.4 yr | 54.9 ± 16.4 yr | 44.8 ± 16.4 yr | 52.3 ± 18.5 yr | 54.1 ± 9.4 yr | 74.3 ± 6.4 yr | 54.2 ± 12.6 yr |
| Mean disease duration (mo) | 17.4 ± 18.8 mo | 10.0 ± 9.6 mo | 17.4 ± 26.5 mo | 19.0 ± 40.7 mo | 21.3 ± 40.0 mo | 7.1 ± 14.1 mo | 24.4 ± 42.3 mo | 5.0 ± 3.6 mo | 4.4 ± 3.5 mo |
| Preoperative JOA score | 6.2 ± 2.5 | 4.8 ± 2.5 | 3.9 ± 2.4 | 6.4 ± 42.8 | 6.2 ± 2.6 | 4.1 ± 2.9 | 3.4 ± 1.5 | 5.3 ± 2.6 | 5.8 ± 3.9 |
| Postoperative JOA score | 8.2 ± 1.9 | 6.8 ± 2.0 | 6.2 ± 1.9 | 8.1 ± 2.1 | 7.3 ± 2.4 | 6.8 ± 1.8 | 5.9 ± 2.0 | 7.3 ± 2.9 | 7.0 ± 3.5 |
| JOA recovery rate (%) | 45.8 ± 21.6 | 35.5 ± 17.2 | 34.3 ± 18.7 | 42.1 ± 28.0 | 29.3 ± 33.0 | 36.5 ± 18.2 | 32.4 ± 18.5 | 47.2 ± 37.4 | 38.2 ± 35.3 |
| Affected level | |||||||||
| Upper | 7 (14.6%) | 8 (26.7%) | 5 (18.5%) | 24 (24.5%) | 16 (25.0%) | 7 (41.2%) | 2 (28.6%) | 0 (0.0%) | 0 (0.0%) |
| Middle | 3 (6.3%) | 19 (63.3%) | 18 (66.7%) | 29 (29.6%) | 16 (25.0%) | 7 (41.2%) | 5 (71.4%) | 1 (25.0%) | 3 (60.0%) |
| Lower | 38 (79.2%) | 3 (10.0%) | 3 (11.1%) | 45 (45.9%) | 32 (50.0%) | 3 (17.6%) | 0 (0.0%) | 3 (75.0%) | 2 (40.0%) |
| Initial/preoperative symptoms | |||||||||
| Girdle pain | 0 (0%)/0 (0%) | 2 (6.7%)/2 (6.7%) | 1 (3.7%)/4 (4.1%) | 4 (4.1%)/2 (7.4%) | 7 (10.9%)/8 (12.5%) | 5 (29.4%)/6 (35.3%) | 0 (0.0%)/0 (0.0%) | 0 (0.0%)/0 (0.0%) | 0 (0.0%)/0 (0.0%) |
| Back pain | 0 (0%)/2 (4.2%) | 3 (10.0%)/3 (10.2%) | 3 (11.1%)/3 (11.1%) | 17 (17.3%)/20 (20.4%) | 16 (25.0%)/17 (26.6%) | 7 (41.2%)/10 (58.8%) | 0 (0.0%)/0 (0.0%) | 2 (50.0%)/2 (50.0%) | 0 (0.0%)/0 (0.0%) |
| Low back pain | 8 (16.7%)/12 (25.0%) | 4 (13.3%)/6 (20.0%) | 2 (7.4%)/3 (11.1%) | 29 (29.6%)/34 (34.7%) | 16 (25.0%)/19 (29.7%) | 3 (17.6%)/3 (17.6%) | 1 (14.3%)/2 (28.6%) | 2 (50.0%)/2 (50.0%) | 2 (40.0%)/2 (40.0%) |
| Leg numbness | 32 (66.7%)/33 (68.8%) | 18 (60.0%)/23 (76.7%) | 17 (63.0%)/21 (77.8%) | 45 (45.9%)/63 (64.3%) | 36 (56.3%)/50 (78.1%) | 6 (35.3%)/10 (58.8%) | 4 (57.1%)/4 (57.1%) | 0 (0.0%)/3 (25.0%) | 1 (20.0%)/2 (40.0%) |
| Leg pain | 8 (16.7%)/10 (20.8%) | 4 (13.3%)/7 (23.3%) | 2 (7.4%)/4 (14.8%) | 22 (22.4%)/28 (28.6%) | 10 (15.6%)/12 (18.8%) | 2 (11.8%)/3 (17.6%) | 1 (14.3%)/1 (14.3%) | 0 (0.0%)/0 (0.0%) | 1 (20.0%)/3 (60.0%) |
| Gait disturbance | 17 (35.4%)/31 (64.6%) | 14 (46.7%)/27 (90.6%) | 14 (51.9%)/23 (85.2)% | 17 (17.3%)/48 (49.0)% | 9 (14.1%)/35 (54.7)% | 3 (17.6%)/15 (88.2)% | 1 (14.3%)/7 (100%) | 0 (0.0%)/3 (25.0%) | 2 (40.0%)/3 (60.0)% |
| Leg paresis | 5 (10.4%)/10 (20.8%) | 2 (6.7%)/13 (43.3%) | 3 (11.1%)/11 (40.7%) | 4 (4.1%)/28 (28.6%) | 4 (6.3%)/17 (26.6%) | 1 (5.9%)/12 (70.6%) | 0 (0.0%)/3 (42.9%) | 0 (0.0%)/3 (25.0%) | 2 (40.0%)/3 (60.0)% |
| BBD | 1 (2.1%)/2 (4.2%) | 2 (6.7%)/4 (13.3%) | 0 (0.0%)/1 (3.7%) | 1 (1.0%)/9 (9.2%) | 3 (4.7%)/6 (9.4%) | 2 (11.8%)/4 (23.5%) | 0 (0.0%)/0 (0.0%) | 0 (0.0%)/0 (0.0%) | 0 (0.0%)/0 (0.0%) |
| Neurologic findings | |||||||||
| Hyper-PTR | 29 (60.4%) | 27 (90.0%) | 24 (88.9%) | 48 (49.0%) | 41 (64.1%) | 13 (76.5%) | 6 (85.7%) | 3 (75.0%) | 4 (80.0%) |
| Hyper-ATR | 25 (52.1%) | 22 (73.3%) | 21 (77.8%) | 43 (43.9%) | 41 (64.1%) | 15 (88.2%) | 5 (71.4%) | 2 (50.0%) | 4 (80.0%) |
| Positive ankle clonus | 16 (33.3%) | 20 (66.7%) | 20 (74.1%) | 28 (28.6%) | 24 (37.5%) | 9 (52.9%) | 3 (42.9%) | 0 (0.0%) | 4 (80.0%) |
ATR = ankle tendon reflex, BBD = bowel bladder disturbance, IET = intradural extramedullary tumor, IMSCT = intramedullary spinal cord tumor, JOA = Japanese Orthopaedic Association, OLF = ossification of the ligamentum flavum, OPLL = ossification of the posterior longitudinal ligament, PTR = patellar tendon reflex, SCH = spinal cord herniation, TDH = thoracic disk herniation, VF = vertebral fracture, VT = vertebral tumor