Visually Assessed Severity of Lumbar Spinal Canal Stenosis Is Paradoxically Associated With Leg Pain and Objective Walking Ability

Pekka Kuittinen; Petri Sipola; Tapani Saari; Timo Juhani Aalto; Sanna Sinikallio; Sakari Savolainen; Heikki Kröger; Veli Turunen; Ville Leinonen; Olavi Airaksinen


BMC Musculoskelet Disord. 2014;15(348) 

In This Article


Clinical Characteristics, Preoperative Symptoms, and Functional Disability

Patient characteristics are summarized in Table 1. The mean age of the study patients (n = 80) at the time of surgery was 63 years (11) [mean (SD)], and 35 (44%) of the subjects were male. Ten patients (13%) had undergone previous spine operation. Coexisting disc herniation was found in 11 patients (14%). According to the ODI scores 7 (9%), 26 (33%), and 36 (45%) had minimal, moderate, and severe disability, respectively, and 11 (14%) patients were crippled. Regarding the overall VAS scores, 28 (35%) patients had minimal pain, 20 (25%) had moderate pain, 22 (28%) had severe pain, and 10 (13%) had crippled pain. Regarding the BDI scale, 63 patients had normal mood and 17 patients were depressed (15 or more points); the mean BDI was 10.4 (6.1). Mean walking distance achieved was 545 (445) m (range, 0–1000 m).

Radiological Findings

According to the visual assessment, none of the patients had a normal central canal. The central canal was moderately and severely stenosed in 36 (45%) and 44 (55%) patients, respectively. Based on the quantitative assessment, the mean minimal dural sac area was 56.1 (21.9) (range, 12–120) mm2. In the quantitative analyses the smallest dural sac was greater than 100 (75–100) mm2, and under 75 mm2 in 4 (5%), 15 (19%), and 61 (76%) patients, respectively.

Correlation of Imaging Findings With Preoperative Symptoms and Functional Disability

The correlation of radiological spinal stenosis and clinical symptoms is summarized in Table 1. VAS leg pain was higher in patients with moderate stenosis than in patients with severe stenosis (7.33 (2.29) vs 5.80 (2.72); P = 0.008) (Figure 2). The walking distance achieved was shorter in patients with radiologically moderate stenosis than in patients with severe stenosis (421 (431) m vs 646 (436) m; P = 0.021) (Figure 3). Patients with severe stenosis at only one level (50%) achieved shorter walking distance than patients with severe stenosis of at least two levels [393 (436) m vs 675 (423) m; P = 0.022]. No correlation was found between the dural sac area measurements and patient symptoms or walking distances achieved (Table 2).

Figure 2.

Visual assessment of the MRI and VAS leg pain n = 80. Mean visual analog scale (VAS) leg pain ±1 standard deviation.

Figure 3.

Walking distance in the treadmill exercise test in patients with moderate and severe spinal stenosis. Mean walking distance ±1 standard deviation.