Intramuscular ketorolac versus osteopathic manipulative treatment in the management of acute neck pain in the emergency department: a randomized clinical trial

Participants

• Number: 58 people (32 female and 26 male).

• Criteria of inclusion: age between 18 and 50 years, patients who presented themselves at the emergency department when one of the three osteopathic physicians participating in the study was present; acute musculoskeletal neck pain (with a duration of less than 3 weeks).

• Criteria of exclusion: (assessed by physical examination, medical history, laboratory tests): bleeding ulcer or peptic ulcer; bone abnormalities; carotid murmur; cerebrovascular events; coagulopathy and bleeding; drug abuse; active lawsuits to receive compensation for injury; hypersensitivity to non-steroidal anti-inflammatory drugs or aspirin; spinal cord infections; joint inflammation; pregnant or lactating women; ligamentous instability; neck surgery; neurological deficits; osteomalacia or osteoporosis; psychiatric disorders; radiculopathy; radiographic contraindications to OMT (evaluated in case of trauma: active inflammatory arthritis including ankylosing spondylitis and rheumatoid arthritis; congenital abnormalities; anteroposterior spinal canal stenosis greater than 11 mm; bone disease including discitis, osteomyelitis, and tuberculosis; acute or unhealed fractures; major misalignments greater than 3 mm translocation or 11% kyphotic angle; neoplastic disease in the cervical region; ossification of the posterior longitudinal ligament; severe osteoporosis; Paget’s disease or septic arthritis); renal failure or collapse; skeletal metastases; spondylolisthesis; fever greater than 37.8°C; substantial trauma with severe injuries, involvement of alcohol or other factors that precluded reliable examination; vertebrobasilar insufficiency; having received treatment for the present case of neck pain by corticosteroids (prolonged use), intramuscular ketorolac, lithium, or manipulations.
• Groups of study: 2 groups obtained by randomization
  • Group 1: OMT, 29 people (18 female and 11 male, mean age 29 years)
  • Gruppo 2: ketorolac, 29 people (14 female and 15 male, mean age 30 years)

Interventions and evaluations

• Assessment of pain intensity by NRS-11 immediately before and one hour after treatment.
• Evaluation of perceived pain relief by PRS-5 one hour after treatment.
• Initial structural examination of the cervical region to assess tissue changes, joint restrictions, and areas of pain. Range-of-motion assessment of the head and neck for evidence of somatic dysfunctions.
• 1 OMT session lasting less than 5 minutes.
• OMT: personalized treatment based on high-velocity low amplitude techniques, soft tissue techniques, and muscle energy techniques.
• Ketorolac: 1 dose of 30 mg intramuscularly.
• OMT performed by three osteopathic physicians who specialize in handling emergencies in emergency rooms.

Results

• Primary outcome: both groups registered a clinically significant decrease in pain, but the OMT group showed a greater change than the ketorolac group in a statistically significant way.
• Secondary outcomes: there was no statistically significant difference between the two groups in perceived pain relief, although a slightly higher number of people reported greater relief in the OMT group.
• Further analysis: 58% of participants experienced neck pain following a road accident.
  Among both groups, 18 participants reported using non-steroidal anti-inflammatory drugs: pain decreased clinically significantly for all, but with no differences between groups. Similarly, no differences emerged in relation to perceived pain relief. For the remaining 40 participants, the OMT group showed a greater decrease in pain than the ketorolac group in a statistically significant way.

OMT reduced pain more than ketorolac in those participants who had previously received OMT (5 in the ketorolac group and 3 in the OMT group), also in a statistically significant manner. In addition, participants in the OMT group also showed greater perception of pain relief than participants in the ketorolac group. In contrast, for the remaining 48 participants, no differences emerged (although the OMT group showed greater pain relief).

The results of the two scales NRS-11 and PRS-5 one hour after treatment were found to be statistically significantly correlated with each other.

• Adverse events: in the ketorolac group, 8 participants reported one or more adverse effects (arm soreness, bad taste in the mouth, dizziness, drowsiness, dyspepsia, tachycardia, light headedness, nausea or vomiting.)
  In the OMT group, one patient reported feeling a “funny arm” after manipulation, but still had normal strength, sensation, and tendon reflexes.

Discussion

OMT has been shown to be equally if not more effective than intramuscular ketorolac in reducing the intensity of acute musculoskeletal neck pain, even achieving clinically significant efficacy. At the level of perceived relief, OMT was equivalent to ketorolac.

The fact that participants who received OMT in the past showed greater improvement than others may have resulted from positive expectations about OMT due to positive past outcomes.

Interestingly, although it did not affect pain relief ratings, the use of non-steroidal anti-inflammatory drugs appears to have influenced the efficacy of OMT. Specifically, OMT appears to have promoted greater pain relief in those who had not taken these drugs. Certainly, further studies are needed to further investigate this finding.

While 1 in 4 participants in the ketorolac group reported adverse effects, only 1 participant who received OMT noticed any adverse effects. This result, as well as the efficacy in reducing pain, are in line with the scientific literature; however, more rigorous and larger studies with a focus on adverse effects are needed, as many studies do not properly consider them and there is a lack of knowledge of possible risk factors that might facilitate their occurrence following OMT.

Despite the results, there are several limits in this study, including the non-blinding of the participants, the lack of sham treatment to compare to OMT, the use of subjective ratings of pain, the failure to calculate the refusal rate (how many people did not want to participate in the study), and the lack of follow-up. Without these limitations, in fact, the study could have led to larger finding, either by encouraging the creation of positive expectations or by including mainly people who wanted to receive OMT or ketorolac. In addition, it is also possible that the dose of ketorolac was not adequate for all participants.