Muscle energy technique for chronic obstructive pulmonary disease, a systematic review

Methods

• Articles analysed: 3
• Search string: a combination of the following terms and of their variation: Chronic Obstructive Pulmonary Disease, COPD, bronchitis and variants; muscle energy technique, MET, post-isometric contraction; randomized controlled trial, controlled clinical trial
• Criteria of inclusion:
  • randomized controlled trials (RCT) written in English, with participants of an age equal or greater than 40 years and with a diagnosis of chronic obstructive pulmonary disease according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria
  • studies in which the intervention consisted of muscle energy techniques or was described in similar terms (eg, techniques directed to the joints or muscles, with active contractions by the patients and passive movements applied by the osteopaths); studies with any type of control (eg, no treatment, sham treatment, standard of care).
• Criteria of exclusion: studies with patients with other pulmonary diseases.

Characteristics of the studies

3 randomized controlled trials (RCT)

• In 2 studies it was not specified how the patients had been distributed into treatment and control group
• People with moderate or severe pulmonary disease
• Evaluation of the quality of the studies through the Cochrane Collaboration Risk of Bias Tool scale
• 1 study of moderate quality and 2 of uncertain quality

Participants

• Number in the smallest study: 30 people, of which 15 in the intervention group and 15 in the control group
• Number in the biggest study: 30 people, of which 15 in the intervention group and 15 in the control group
• Total: 90 people
• Mean age: from 40 to 70 years

Interventions and evaluations

• 1 session, 3 sessions or 24 sessions (2 per week) of the intervention
• In the treatment groups: muscle energy techniques alone, muscle energy techniques with conventional physical therapy, muscle energy techniques with exercises
• 2 studies specified the muscles involved
• In the control groups: sham treatment with conventional physiotherapy, conventional physiotherapy alone, sham treatment with exercises

Results

• Primary outcomes: in relation to pulmonary function, the muscle energy techniques in combination with conventional physiotherapy did not result more effective compared to the control (sham treatment with conventional physiotherapy).
• Secondary outcomes: with regard to the physical exercise capacity, compared to sham treatment, the muscle energy techniques favored a statistically significant improvement when added to conventional physiotherapy or to an exercise program.

Two studies have evaluated perceived effort (intended as dyspnoea index) through the Borg scale, showing a statistically significant improvement in groups with muscle energy techniques.

One study reported, with statistical significance, a better quality of life measured through the Clinical COPD Questionnaire (CCQ) thanks to muscle energy techniques.
Two adverse effects were found in only one study, but they were difficult to link to the interventions as they related to other systemic diseases experienced by patients (kidney stones and Crohn’s disease)

Discussion

Muscle energy techniques appear to have positive effects on patients with chronic obstructive pulmonary disease, although more structured and large studies are needed to assess their actual impact.

It should be noted, however, that some of the effects obtained were not only significant from a statistical point of view, but also clinical, that is to say, they resulted in an effective improvement of the patients’ health. In particular, the exercise capacity measured through the walking test, the perceived dyspnoea measured on the Borg scale and the quality of life measured through CCQ have improved.

The lack of effects on pulmonary function is in line with other studies also reporting that manual therapies, in addition to physiotherapy or an exercise program, do not seem to make a particular contribution.

Although no adverse effects were found, it is also true that only one study evaluated them and it is not always clear what should be considered as an adverse effect of manual therapy.
Therefore, more rigorous studies are needed, where the interventions are better described in order to be clear and repeatable, as well as the outcomes (better described and reported during the study, with a transparent statistical analysis).