Table 1.
Patient baseline demographic characteristics, comorbidities, and health status measures according to whether the patient had revision surgery within 8 years of index surgery.
| SPS | Had Revision Surgery (n=77)* |
No Revision Surgery (n=345) |
p-value*** |
|---|---|---|---|
| Mean Age (SD) | 62.4 (10.2) | 64.2 (12.5) | 0.24 |
| Female - no. (%) | 25 (32%) | 137 (40%) | 0.29 |
| Ethnicity: Not Hispanic† | 75 (97%) | 330 (96%) | 0.70 |
| Race - White | 63 (82%) | 292 (85%) | 0.66 |
| Education - At least some college | 48 (62%) | 217 (63%) | 0.97 |
| Marital Status - Married | 56 (73%) | 250 (72%) | 0.92 |
| Work Status | 0.75 | ||
| Full or part time | 30 (39%) | 119 (34%) | |
| Disabled | 8 (10%) | 32 (9%) | |
| Retired | 33 (43%) | 155 (45%) | |
| Other | 6 (8%) | 39 (11%) | |
| Compensation - Any‡ | 6 (8%) | 24 (7%) | 0.99 |
| Mean Body Mass Index (BMI), (SD)§ | 30 (5) | 29.3 (5.3) | 0.30 |
| Smoker | 7 (9%) | 31 (9%) | 0.85 |
| Comorbidities | |||
| Hypertension | 33 (43%) | 149 (43%) | 0.94 |
| Diabetes | 13 (17%) | 45 (13%) | 0.48 |
| Osteoporosis | 3 (4%) | 29 (8%) | 0.27 |
| Heart Problem | 17 (22%) | 86 (25%) | 0.70 |
| Stomach Problem | 21 (27%) | 66 (19%) | 0.15 |
| Bowel or Intestinal Problem | 10 (13%) | 40 (12%) | 0.88 |
| Depression | 6 (8%) | 41 (12%) | 0.41 |
| Joint Problem | 41 (53%) | 186 (54%) | 0.98 |
| Other¶ | 28 (36%) | 117 (34%) | 0.78 |
| Time since most recent episode > 2 years | 22 (29%) | 63 (18%) | 0.06 |
| SF-36 scores, mean(SD)|| | |||
| Bodily Pain (BP) | 32.5 (18.8) | 30.6 (19) | 0.42 |
| Physical Functioning (PF) | 34.6 (25.1) | 31.5 (21.4) | 0.26 |
| Physical Component Summary (PCS) | 29.2 (8.5) | 29.1 (8) | 0.89 |
| Mental Component Summary (MCS) | 50.1 (11) | 48.3 (12.2) | 0.23 |
| Oswestry (ODI)** | 44.5 (18.4) | 45.5 (18) | 0.67 |
| Stenosis Frequency Index (0–24)†† | 15.1 (5.3) | 14.9 (5.6) | 0.72 |
| Stenosis Bothersome Index (0–24)‡‡ | 15.5 (5) | 15.3 (5.6) | 0.79 |
| Back Pain Bothersomeness§§ | 4.4 (1.7) | 4.1 (1.8) | 0.19 |
| Leg Pain Bothersomeness¶¶ | 4.5 (1.5) | 4.5 (1.6) | 0.72 |
| Satisfaction with symptoms - very dissatisfied | 56 (73%) | 267 (77%) | 0.47 |
| Problem getting better or worse | 0.17 | ||
| Getting better | 0 (0%) | 15 (4%) | |
| Staying about the same | 22 (29%) | 96 (28%) | |
| Getting worse | 54 (70%) | 228 (66%) | |
| Treatment preference | 0.99 | ||
| Preference for non-surg | 16 (21%) | 71 (21%) | |
| Not sure | 13 (17%) | 56 (16%) | |
| Preference for surgery | 48 (62%) | 218 (63%) | |
| Pseudoclaudication - Any | 62 (81%) | 279 (81%) | 0.93 |
| SLR or Femoral Tension | 17 (22%) | 72 (21%) | 0.94 |
| Pain radiation - any | 58 (75%) | 271 (79%) | 0.64 |
| Any Neurological Deficit | 33 (43%) | 195 (57%) | 0.04 |
| Reflexes - Asymmetric Depressed | 18 (23%) | 91 (26%) | 0.69 |
| Sensory - Asymmetric Decrease | 19 (25%) | 108 (31%) | 0.31 |
| Motor - Asymmetric Weakness | 20 (26%) | 90 (26%) | 0.90 |
| Stenosis Levels | |||
| L2–L3 | 22 (29%) | 106 (31%) | 0.81 |
| L3–L4 | 52 (68%) | 234 (68%) | 0.93 |
| L4–L5 | 68 (88%) | 321 (93%) | 0.24 |
| L5-S1 | 24 (31%) | 85 (25%) | 0.30 |
| Stenotic Levels (Mod/Severe) | 0.31 | ||
| None | 1 (1%) | 5 (1%) | |
| One | 25 (32%) | 124 (36%) | |
| Two | 37 (48%) | 128 (37%) | |
| Three+ | 14 (18%) | 88 (26%) | |
| Stenosis Locations | |||
| Central | 68 (88%) | 297 (86%) | 0.74 |
| Lateral Recess | 63 (82%) | 280 (81%) | 0.98 |
| Neuroforamen | 21 (27%) | 106 (31%) | 0.65 |
| Stenosis Severity | 0.24 | ||
| Mild | 1 (1%) | 5 (1%) | |
| Moderate | 38 (49%) | 134 (39%) | |
| Severe | 38 (49%) | 206 (60%) | |
| Taking antidepressants | 1 (1%) | 11 (3%) | 0.60 |
Seventy-seven patients underwent revision surgery within 8 years of index surgery. The 77 patients who had revision surgery and 345 patients who had no revision surgery had at least one follow-up through 8 years and were included in the current study. The index surgery is within 8 years of enrollment.
Race or ethnic group was self-assessed. Whites and blacks could be either Hispanic or non-Hispanic.
This category includes patients who were receiving or had applications pending for workers compensation, Social Security compensation, or other compensation.
Body-mass index is the weight in kilograms divided by the square of the height in meters.
Other = problems related to stroke, cancer, fibromyalgia, CFS, PTSD, alcohol, drug dependency, lung, liver, kidney, blood vessel, nervous system, migraine or anxiety.
T∂he SF-36 scores range from 0 to 100, with higher score indicating less severe symptoms.
The Oswestry Disability Index ranges from 0 to 100, with lower scores indicating less severe symptoms.
The Stenosis Frequency Index ranges from 0 to 24, with lower scores indicating less severe symptoms.
The Stenosis Bothersomeness Index ranges from 0 to 24, with lower scores indicating less severe symptoms.
The Low Back Pain Bothersomeness Scale ranges from 0 to 6, with lower scores indicating less severe symptoms
The Leg Pain Bothersomeness Scale ranges from 0 to 6, with lower scores indicating less severe symptoms.
The association of baseline demographic characteristics, comorbidities, and health status measures with revision surgery was investigated via chi-square tests for categorical variables and a t-test for continuous variables.