Is therapeutic ultrasound effective in the treatment of chronic low-back pain?  

Relevance of this review

Chronic peripheral arterial occlusion (of lower extremities) affects approximately 202 million people globally over the age of 40. In high-income countries the prevalence is 5.41% of men and 5.28% of women under age 50, increasing to 18.83% in men and 18.38% in women over 80. The most common symptom is intermittent claudication (IC), defined as a cramping pain in the muscles of the leg (or both legs) during exercise that is relieved by a short period of rest.

This pain is due to a partial blockage of arteriosus blood flow in the leg vessels caused by fatty deposits, resulting in reduced pain-free walking capacity, restricting the patients' mobility, daily-activity, and diminished health-related quality of life (HRQoL). Moreover, people with IC have a high risk of cardiovascular events.

International guidelines recommend a multidisciplinary management of these patients including cardiovascular risk assessment, lifestyle counselling, and exercises (supervised by a physical or exercise therapist).

The aim of walking exercises is to increase the pain-free walking distance (PFWD).

Alternative therapy includes cycling, lower-extremity resistance training, upper-arm ergometry, Nordic-walking (walking with specially designed poles for upper and lower body exercise), and combination modes.

Unfortunately, due to comorbidities (such as arthrosis, chronic obstructive pulmonary disease, stroke, or cardiac complaints), all patients are not able to complete the exercise protocol. For these patients, an adjusted protocol or alternative exercise regimen may be proposed for improving therapy adherence. According to the Physical Activity Guidelines, the combinations of aerobic and muscle strengthening activities might provide health benefits. Thus, the objective of this review is to assess effectiveness of supervised alternative-exercise programmes compared to supervised walking programmes

This review is important for:

Patients with intermittent claudication (IC), parents/caregivers, health professionals dealing with IC, researchers, general practitioners, and policymakers.

Key outcomes of the review

The review included 10 randomized studies (published up to March 2019), comprising 527 adult participants with IC symptoms. Analysis showed no significant differences between alternative exercises and a walking program for mean walking distance (MWD), pain-free walking distance (PFWD) and on walking-impairment questionnaire (WIQ). Similarly no differences were detected at 12 weeks or at the end of training (24 weeks).

Authors’ conclusions

This review found no clear difference between alternative exercise modes and supervised walking exercise in improving the maximum and pain-free walking distance in patients with IC. Clinical inconsistency, small sample size, and risk of bias concerns yielded low-certainty evidence. Alternative exercise modes may be useful when supervised walking exercise is not an option.

Future recommendations

More randomized controlled trials (RCTs) with robust methodology, clinical consistency, larger sample size, sufficient power, and low bias risks are needed to provide stronger evidence for comparing different types of supervised exercise programmes in IC. In particular future RCTs should investigate outcome measures on walking behaviour, physical activity, cardiovascular risk, and HRQoL, using standardised testing methods and outcomes reporting to allow meaningful comparison across studies.

Comment by Sunita Gudwani