Efficacy and safety of osteopathic manipulative treatment: an overview of systematic reviews

Methods

• Articles analysed: 9
• Stringa di ricerca: a combination of the following terms: osteopathic, treatment, medicine, manipulation, review, “systematic review” and meta-analysis
• Criteria of inclusion: RCTs from systematic reviews or meta-analyses; RCTs from systematic reviews with unclear inclusion criteria;  evaluating clinical endpoints as outcomes; any type of patient (sex, age, etc. ) and clinical condition; OMT performed by osteopaths, osteopathic physicians, or osteopathic students; standardized or individualized OMT, always based on osteopathic principles; any type of control (sham, or sham treatment, light touch, waiting list, no treatment, physiotherapy, standard of care, alternative therapies); any therapeutic setting.
• Criteria of exclusion: reviews of the literature, protocols, commentaries, personal contributions, unpublished studies, and studies that applied manual therapies other than OMT to the experimental group.

Characteristics of the studies

• 6 reviews on musculoskeletal problems
  • 4 reviews on low back pain (22 studies and 2,053 people)
  • 1 review on neck pain (3 studies and 123 people)
  •  1 review on chronic non cancer pain (16 studies and 728 people)
• 1 review in the pediatric field (17 studies and 887 children)
• 1 review on neurologic conditions (5 studies and 235 people)
• 1 review on visceral conditions (5 studies and 204 people)
• in total: 57 different studies (without counting the repetitions)
• evaluation of the quality of the systematic reviews through AMSTAR-2, and of the single RCTs through the Cochrane criteria for risk of bias (RoB).
  • a large proportion of RCTs were considered of high risk of bias
  • 7 reviews were considered of low quality, while 2 reviews contained critical elements

Participants

• Total number: 3,740 different people (without counting the repeated studies)

Interventions and evaluations

• In the OMT groups:
  • variable, according to the study.
•  In the control groups:
  • no treatment, sham treatment (manual or ultrasound).

Results

• Primary outcomes:
  • low back pain: there are inconclusive results due to studies of low quality or high heterogeneity. OMT may promote improvement in pain and functional status in chronic low back pain and low back pain during pregnancy;
  • neck pain: OMT has been shown to improve neck pain, but it does not appear to have a major effect on functional status. Again, the individual studies analyzed show a high risk of bias;
  • Chronic non-cancer pain: OMT can reduce musculoskeletal pain with related disability and improve quality of life;
  • pediatric conditions: it appears like low-quality studies reported effects in favor of OMT, while high-quality studies have failed to find such effects. The pediatric conditions that actually obtained some sort of improvement were: congenital tear duct obstruction, weight gain, infant colic, postural asymmetry, dysfunctional urination, and length of hospitalization;
  • neurological condition: although the results have shown positive effects of OMT on migraine and tension headache, the high level of bias and heterogeneity of the studies does not allow sound conclusions in support of these results;
  • visceral conditions: despite high heterogeneity, OMT appears to have positively improved health in cases of irritable bowel syndrome.
• Secondary outcomes:  although many studies did not analyze the occurrence of adverse effects, the other studies found mild adverse effects (stiffness and fatigue). One case of post-OMT back muscles’ spasticity was found in the adult population and 4 cases of worsening vegetative condition in the pediatric population.

Discussion

The most important outcome we have come across in this analysis is the methodological deficiency of osteopathic reasearch studies, a deficiency that necessarily reflects on the quality of the studies and on the usefulness  conclusions drawn.

In particular, despite many reminders within the osteopathic community itself, little space is given to an adequate description of sham treatments, which, nonetheless, should be used as a control for OMT in all studies in order to promote the blinding of participants.

In addition, the description of the OMT performed and how outcomes are measured is also often superficial, both in studies and systematic reviews. It would be good if authors followed guidelines such as the Template for Intervention Description and Replication both guide and checklist (TIDieR) and the CONsolidated Standards of Reporting Trials (CONSORT). This increases the possibility of replicating the study and, thus, verifying the results obtained.

Concretely, OMT appears to be quite promising in treating musculoskeletal disorders, particularly in reducing pain, but is limited in pediatric, visceral and neurological conditions (headaches). These conclusions are closely related to the low quality of the studies, particularly the small samples examined and the heterogeneity of samples, treatments, and measured outcomes, which prevents an effective comparison of the results.

Regarding adverse effects, OMT seems safe as very few adverse effects have been reported. However, there are few studies, including systematic reviews, that report the definition of adverse effects and how they are detected. This also needs to be improved for OMT to be considered completely safe.

The limitations of this review lie in the inclusion criteria, which were quite restricted in both the type of studies (only systematic reviews of RCTs) and the type of practitioner (only osteopaths and osteopathic physicians, students or professionals). These choices were made because RCTs are the gold standard and because it was considered that the use of osteopathic techniques by non-osteopaths could produce  treatments not in line with the osteopathic principles.