Spine Center, Schulthess Klinik, Lengghalde 2, 8008 Zürich, Switzerland.
Spine J. 2011 Sep;11(9):849-57. doi: 10.1016/j.spinee.2011.08.004. Epub 2011 Sep 8.
Many studies report an association between low back pain (LBP) and reduced back muscle endurance and consider this to indicate muscular dysfunction. However, few have investigated the potentially confounding influence of psychological factors on performance during such endurance tests.
This study examined whether psychological factors were associated with "underperformance" on the Biering-Sørensen (BS) test (ie, not performing as well as one is physiologically capable of).
STUDY DESIGN/SETTING: Cross-sectional study of the baseline data of patients with chronic (>3 months) nonspecific LBP (cLBP) before participation in a clinical trial of exercise therapy.
One hundred forty-eight patients with cLBP (43% men; age, 45±10 years).
The time for which the modified BS isometric endurance test could be performed to exhaustion minus the time that would have been predicted based on the rate of decline in median frequency of the surface electromyographic (EMG) signal recorded bilaterally from the erector spinae at L3 and L5.
Back pain and disability, psychological disturbance, catastrophizing, fear-avoidance beliefs, back beliefs, and exercise self-efficacy were measured using validated questionnaires. Patients performed the BS test to exhaustion while physiological muscle fatigability was measured from continuous surface EMG recordings.
Multivariable regression analysis controlling for gender revealed that greater psychological disturbance (p=.003) and more negative back beliefs (p=.015) were unique predictors of the extent of "underperformance," accounting for 22.3% variance in expected endurance time minus actual time.
It is important that the underlying nature (psychological or physiological) of performance deficits be identified during such tests because this may influence the interpretation of prospective studies reporting risk factors for LBP and dictate the particular treatment or interventional approach required to remedy the situation in individuals with LBP.
许多研究报告称，腰痛（LBP）与背部肌肉耐力降低有关，并认为这表明肌肉功能障碍。然而，很少有研究调查心理因素对这种耐力测试表现的潜在混杂影响。
本研究旨在探讨心理因素是否与 Biering-Sørensen（BS）测试（即表现不如生理能力）中的“表现不佳”有关。
研究设计/设置：在参加运动疗法临床试验之前，对患有慢性（>3 个月）非特异性 LBP（cLBP）的患者进行基线数据的横断面研究。
148 例 cLBP 患者（43%为男性；年龄，45±10 岁）。
从双侧竖脊肌表面肌电图（EMG）信号的中位频率下降率预测的时间中减去 Modified BS 等长耐力测试直至疲劳的时间。
使用经过验证的问卷测量腰痛和残疾、心理困扰、灾难化、回避恐惧信念、背部信念和运动自我效能。患者在疲劳时进行 BS 测试，同时通过连续表面 EMG 记录测量生理肌肉疲劳性。
多变量回归分析控制性别后发现，更大的心理困扰（p=.003）和更消极的背部信念（p=.015）是“表现不佳”的独特预测因素，占预期耐力时间减去实际时间的 22.3%。
在进行此类测试时，重要的是要确定表现缺陷的潜在性质（心理或生理），因为这可能会影响报告 LBP 风险因素的前瞻性研究的解释，并决定需要对 LBP 患者采取特定的治疗或干预措施来纠正这种情况。
