Background Most outcome measures for patients with sciatica only inquire about pain or pain-related disability. Almost no information exists about the clinical course of paresthesia and self-reported motor symptoms.
Objectives To explore the 2 year prognosis of self-reported paresthesia and weakness as compared with leg pain in patients with sciatica and lumbar disc herniation.
Methods This study was part of an observational cohort study including 466 patients referred to secondary care. The patients included had radiating pain or paresis below the knee and ipsilateral lumbar disc herniation at the corresponding level verified by a magnetic resonance imaging or computed tomography scan. Self-report data were obtained by mailed questionnaires at 3, 6, 12 and 24 months. The bothersomeness of each symptom was rated on a scale from 0 to 6; a symptom score of 4–6 was defined as bothersome. Multivariate associations were analysed by logistic regression with adjustments for surgical therapy.
Results Here we present the results of the 380 patients (81.5%) who completed the 2 year follow-up. Self-reported paresthesia, weakness and leg pain improved during follow-up. At 2 years, 18.2% of the patients reported bothersome paresthesia, 16.6% reported bothersome leg pain, and 11.5% reported bothersome weakness. Among those with little or no leg pain at 2 years, 6.7% reported bothersome paresthesia and 5.1% reported bothersome weakness. The correlation coefficients (Spearman rho) were: paresthesia and weakness, 0.69; paresthesia and leg pain, 0.73; and weakness and leg pain, 0.63.
During the follow-up period, 121 (31.8%) patients received surgical therapy. At baseline, the surgical patients reported significantly more paresthesia (3.7 (SD 1.9) versus 3.1 (SD 1.8), p<0.01) but not significantly more weakness (2.7 (SD 2.0) versus 2.4 (SD 2.0), p=0.14) than the non-surgical patients. The mean differences in the change from baseline to 2 years between surgical and non-surgical patients were: paresthesia, 1.0 [95% confidence interval (CI): 0.5, 1.5] and weakness, 0.9 (95% CI: 0.5, 1.3).
In multivariate models, bothersome paresthesia and bothersome weakness at 2 years were both independently and significantly associated with baseline impaired sensibility, bothersome back pain and bothersome weakness. A longer duration of back problems and older age were significantly associated with bothersome paresthesia. When surgical treatment was added to the multivariate models, this variable became borderline significantly negatively associated with bothersome weakness (OR=0.42, 95% CI: 0.19, 0.96) but not with bothersome paresthesia.
Conclusions Self-reported paresthesia and weakness both improved during 2 years of follow-up. Patients considered that paresthesia was somewhat more bothersome than weakness. At the end of the 2-year follow-up period, the percentage of patients who reported bothersome paresthesia was similar to the percentage who reported bothersome leg pain. Surgical therapy during follow-up was borderline significantly negatively associated with bothersome weakness at 2 years but not with bothersome paresthesia. Information about paresthesia and self-reported weakness is important in the assessment of how sciatica affects patients.
Disclosure of Interest None Declared