Table 3.
Associations between candidate predictors and nonoperative lumbosacral radiculopathy treatment failure at 2-year followup*
| Prognostic factor | Bivariate associations | Multivariate associations | ||
|---|---|---|---|---|
| Odds ratio (95% CI) | p value | Odds ratio (95% CI) | p value | |
| Predictors of treatment failure defined as subsequent surgery (n = 154; 26 participants underwent surgery) | ||||
| Initial leg pain intensity (VAS) [30] | 1.25 (1.02–1.53) | 0.03 | 1.22 (0.98–1.53) | 0.08 |
| Initial disability (ODI) [20] | 1.01 (0.99–1.03) | 0.40 | – | – |
| Duration of symptoms (weeks) [28] | 0.95 (0.82–1.10) | 0.53 | – | – |
| Prior low back pain [30] | 4.70 (1.06–20.9) | 0.04 | 4.79 (1.01–22.7) | 0.05 |
| Straight leg raise test [28] | 4.68 (1.83–12.0) | 0.001 | 4.38 (1.60–11.9) | 0.004 |
| Crossed straight leg raise test [30] | 3.09 (0.83–11.5) | 0.09 | 1.25 (0.29–5.37) | 0.77 |
| Femoral stretch test [30] | 0.85 (0.29–2.46) | 0.77 | – | – |
| Predictors of treatment failure defined as persistent leg pain after nonoperative treatment† (n = 92; 42 participants with persistent leg pain) | ||||
| Initial leg pain intensity (VAS) [11] | 1.07 (0.90–1.27) | 0.43 | – | – |
| Initial back pain intensity (VAS) [11] | 0.91 (0.79–1.04) | 0.16 | – | – |
| Female sex [12] | 0.92 (0.40–2.14) | 0.85 | – | – |
| Duration of symptoms (weeks) [23] | 0.95 (0.83–1.09) | 0.45 | – | – |
| Smoking [11] | 0.80(0.28–2.33) | 0.68 | – | – |
| Medical comorbidities (SACQ) [11] | 1.11 (0.97–1.27) | 0.12 | 1.13 (0.98–1.30) | 0.10 |
| Workers compensation [3] | 8.17 (0.94–71) | 0.06 | 9.04 (1.01–81) | 0.05 |
| Muscle weakness (any) [11] | 0.98 (0.43–2.26) | 0.96 | – | – |
| Disc extrusion [12] | 1.15 (0.48–2.76) | 0.76 | – | – |
| Disc sequestration [12] | 0.18 (0.02–1.55) | 0.12 | 0.30 (0.03–2.73) | 0.29 |
| Predictors of treatment failure defined as persistent disability after nonoperative treatmentǂ (n = 94; 19 participants with persistent disability) | ||||
| Initial disability (ODI) [11] | 1.02 (1.00–1.05) | 0.11 | 1.03 (0.99–1.06) | 0.11 |
| Initial back pain intensity (VAS) [11] | 1.01 (0.85–1.19) | 0.94 | – | – |
| Female sex [12] | 3.64 (1.27–10.4) | 0.02 | 3.16 (1.03–9.69) | 0.05 |
| Duration of symptoms (weeks) [23] | 1.16 (0.99–1.35) | 0.06 | 1.16 (0.98–1.37) | 0.08 |
| Smoking [11] | 1.88 (0.57–6.18) | 0.30 | – | – |
| Medical comorbidities (SACQ) [11] | 1.09 (0.95–1.25) | 0.24 | – | – |
| Prior low back pain [11] | 0.67 (0.23–1.92) | 0.45 | – | – |
| Workers compensation [3] | 6.40 (1.29– 31.6) | 0.02 | 5.99 (1.09–32.7) | 0.04 |
| Disc extrusion [12] | 1.08 (0.37–3.19) | 0.88 | – | – |
| Disc sequestration [12] | NA§ | – | – | |
| Abnormal deep tendon reflex [11] | 0.87 (0.30–2.56) | 0.80 | – | – |
| Predictors of treatment failure defined as participant-reported lack of recovery after nonoperative treatment (n = 94; 44 participants with recovery) | ||||
| Age (per year) [14] | 1.00 (0.98–1.03) | 0.80 | – | – |
| Female sex [21] | 2.20 (0.94–5.16) | 0.07 | 2.44 (1.02–5.84) | 0.05 |
| Duration of symptoms (weeks) [31] | 0.97 (0.85–1.11) | 0.69 | – | – |
| Smoking [21] | 2.46 (0.79–7.66) | 0.12 | 2.84 (0.89–9.12) | 0.08 |
| Workers compensation [3] | 2.33 (0.43–12.7) | 0.33 | – | – |
| Straight leg raise test [31] | 1.78 (0.74–4.25) | 0.20 | – | – |
| Femoral stretch test [31] | 1.58 (0.59–4.27) | 0.37 | – | – |
| Herniation location [32] (foraminal) | 1.73 (0.73–4.07) | 0.21 | – | – |
* All predictor variables with bivariate associations with p ≤ 0.15 were included simultaneously in the multivariable models; statistically significant p values (≤ 0.05) in bold; †pain intensity ≥ 1 on VAS [12]; ǂdisability < 20 on ODI [9]; §odds ratio not calculable as a result of all participants with disc sequestrations reporting no/mild disability at followup; this association was not statistically significant when tested using Fisher’s exact test (data not shown); CI = confidence interval; VAS = visual analog scale; ODI = Oswestry Disability Index; SACQ = Self-Acquired Comorbidity Questionnaire [13].