Table 4 Randomized controlled trials (RCTs) of physiotherapy and spinal manipulative therapy for CEH

Physiotherapy

The Netherland [30]

43 participants (16M, 27F)

Age 18–65 years

Mean age 36 years

CEH mean duration >6 months and at least one of four signs of temporomandibular disorder (TMD)

CEH diagnosed by neurologist

RCT of 7–7½ months duration conducted by a physiotherapist, i.e.

Baseline evaluation

3- to 6-week treatment

6-month follow-up

Comparison of baseline, post-treatment and at 6-month follow-up

Six interventions ≤30-min within 3–6 weeks

The physiotherapist selected the technique and treatment and exercise he or she considered to be beneficial for the participant

The experimental group received accessory (translatory) movements of temporomadibular region and/or masticatory muscle techniques such as trigger point treatment and muscle stretching. Active and passive movement facilitating optimal function of cranial nerve tissue, coordination exercises and home exercises. The therapist could also opt for additionally neuromusculoskeletal treatments for cervical region

(n = 20) (7M, 13F)

Conventional physiotherapy including manual techniques at the cranio-cervical region and exercises

(n = 18) (6M, 12F)

Drop outs (n = 5)

The experimental group showed a significant reduction in headache intensity 3- and 6-month post-treatment as compared to conventional physiotherapy (p < 0.001)

The pain intensity was seven on a colored analog scale (comparable to VAS) at baseline and reduced to 3.2 and 2.1 at 3- and 6-month post-treatment in the experimental group, while the pain was stable around 6.8 in the conventional physiotherapy group at the three recordings

Spinal manipulative therapy (SMT)

Denmark [24]

39 participants (17M, 22F)

Age 20–57 years

Mean 39 years

Headache ≥5 days per month for at least 3 months

CEH diagnosed by a physician and chiropractor

RCT of 6-week duration conducted by a chiropractor, i.e.

2-week baseline

3-week treatment

1-week follow-up

Comparison of pre-treatment at week 2 and post-treatment at week 6

Headache diary

Cervical SMT by chiropractor i.e. toggle recoil at upper cervical and diversified technique at lower cervical determined by the chiropractor

(n = 20) (9M, 11F)

Soft tissue (ST) work including deep friction massage at cervico-thoracic area and laser therapy at upper cervical region

(n = 18) (8M, 10F)

Drop outs (n = 1)

Mean headache duration was reduced in both the CSMT and ST group (p < 0.0001 and p < 0.002, respectively), i.e. a 59 and 52 % reduction from pre- to post-treatment. Mean headache duration reduction was not statistically significant in the two groups

Mean headache intensity was reduced in the cervical SMT group (p < 0.001), but not in ST group, i.e. a 36 and 22 % reduction from pre- to post-treatment

Mean headache intensity reduction was not statistically significant in the two groups

Denmark [25]

54 participants (23M, 31F)

Age 20–60 years

Mean 37 years

Headache ≥5 days per month for at least 3 months

CEH diagnosed by physician and chiropractor

RCT of 5-week duration conducted by a chiropractor, i.e.

1-week baseline

3-week treatment

1-week follow-up

Comparison of pre-treatmen at week 1 and post-treatment at week 5

Headache diary

Cervical SMT by chiropractor i.e. toggle recoil at upper cervical and diversified technique at lower cervical determined by the chiropractor

(n = 28) (13M, 15F)

Soft tissue (ST) work including deep friction massage at cervico-thoracic area and laser therapy at upper cervical region

(n = 25) (10M, 15F)

Drop outs (n = 1)

Median headache duration was reduced in both cervical SMT and ST group (p < 0.0001 and p < 0.04, respectively), i.e. a 69 and 37 % reduction from pre- to post-treatment

Median headache duration was reduced more in the cervical SMT than in the ST group (p < 0.03)

Median headache intensity was reduced in the cervical SMT group (p < 0.0015), but not in ST group, i.e. a 36 and 17 % reduction from pre- to post-treatment. Median headache intensity was reduced more in the cervical SMT than in the ST group (p < 0.04)

Australia [26]

200 participants (60M, 140F)

Age 18–60 years

Mean 36.7 years

Mean headache duration 6.1 years

CEH diagnosed by GPs or physiotherapists

RCT of 12-month duration conducted by physiotherapists i.e.

2-week baseline

6-week treatment

3-, 6- and 12-month follow-up

Comparison of baseline, immediately following post-treatment and 12-month follow-up

Headache diary recording

Cervico-scapular muscle exercise twice a day

(n = 52) (9M, 43F)

Cervical SMT a total of 8-12 treatments ≤30-min

(n = 51) (19M, 32F)

Combined cervical SMT and cervico-scapular muscle exercise

(n = 49) (21M, 28F)

Control group (no treatment)

(n = 48) (11M, 37F)

Drop outs (n = 7)

Headache frequency and intensity were reduced immediately following post-treatment and at 12-month follow-up in all intervention groups as compared to the control group (p < 0.001–0.05)

A 50 % reduction in headache frequency was noted in 76 % in cervico-scapular muscle excercise group, 71 %, in the cervical SMT group, 81 % in the combined cervical SMT and exercise group and 29 % of the control group, while 100 % reduction was observed in 31, 33, 42 and 4 % of the four groups

Headache duration was reduced in the cervical SMT and the combined cervical SMT and exercise group immediately following post-treatment (p < 0.05 and 0.001 respectively) and in the combined cervical SMT and exercise group at 12-month follow-up (p < 0.05)

USA [27]

24 participants

(4M, 19F, 1 unknown)

Mean age 40.3 years

Mean headache duration >3 months

CEH diagnosed by chiropractor

RCT of 12-week duration conducted by three chiropractors, i.e.

baseline evaluation

3-week treatment

Follow-up at weeks 4 and 12

Comparison of baseline, 4 (1 week post-treatment) and 12-week follow-up

Headache diary recording

All participants received cervical SMT by the diversified technique, with an option for additional two physical modalities, i.e. heat and soft tissue therapy including massage and trigger point therapy. Treating chiropractor could also recommend modifications of daily activities and rehabilitative exercises

SMT 1 time per week

(n = 7) (2M, 5F)

SMT 3 times per week

(n = 8) (2M, 8F)

SMT 4 times per week

(n = 8) (8F)

Drop outs (n = 1)

At 4-week follow-up headache intensity (see result text for details) was significantly reduced in SMT 4 times a week group as compared to SMT one time a week group, and at 12-week follow-up headache intensity was significantly reduced in both the SMT 3 and 4 times a week groups as compared to the SMT 1 time a week group

At 4- and 12-week follow-up the mean headache intensity was reduced 21 and 4 % in the SMT 1 time a week group, 49 and 44 % in the SMT 3 times a week group and 58 and 38 % in the SMT 4 times a week group

At 4- and 12-week follow-up the mean headache frequency improved 41, 45, 61 %, and 14, 36, 53 % in the SMT 1, 3 and 4 groups, respectively

Germany [28]

52 participants (21M, 31F)

Age 7–15 years

Mean age 11.6 years

At least headache once a week for at least 6 months

CEH diagnosed by physician

Prospective RCT of 4-month duration conducted by a physician, i.e.

2-month baseline

One treatment

2-month follow-up

Comparison of baseline, post-treatment, follow-up

Headache diary recording

Cervical SMT by physician

(n = 24)

Sham cervical manipulation (Placebo)

(n = 28)

Drop outs (n = 4)

Both the treatment and sham group had a statistically significant reduction in headache days from baseline to 2-month follow-up (p = 0.009 and p = 0.027), i.e. from 40.4 to 30.7 % days with headache, and from 41.2 to 31.8 % days with headache

Headache frequency, total duration and intensity showed no statistical significant change in neither of the two groups

No statistically significant differences were found between the two group in relation to the headache variables described above

USA [29]

80 participants (16M, 64F)

Mean age 36 years

Mean headache duration >3 months

CEH diagnosed by chiropractor

Prospective RCT of 6-month duration conducted by four chiropractors, i.e.

Baseline evaluation

8-week treatment

Follow-up at weeks 12 and 24

Comparison of baseline, 12- and 24-week follow-up

Headache diary recording

All interventions received 10 min visits by chiropractors

One cervical and upper thoracic SMT treatment every week, with prior optional 5 min moist heat pack and 2 min light massage and 8 visit including control physical examinations but no treatment

(n = 20) (4M, 16F)

Two cervical and upper thoracic SMT every week, with prior optional 5 min moist heat pack and 2 min light massage

(n = 20) (4M, 16F)

One 5 min of moist heat followed by 5 min light massage every week and eight control physical examination but no treatment

(n = 20) (5M, 15F)

Two 5 min of moist heat followed by 5 min light massage every week

(n = 20) (3M, 17F)

Drop outs (n = 7)

Headache intensity at 4, 12 and 24 weeks improved more in the SMT group than in light massage group that received treatment twice a week (p < 0.05), while a similar comparison among those whom received treatment once a week was not statistical significant

At 24 weeks mean headache intensity was reduced 35 and 45 % in the SMT groups treated once or twice a week, while it was reduced 27 and 17 % in the similar light massage groups

At 24 weeks a 50 % reduction in pain intensity was achieved by 28 and 47 % in the SMT groups treated once or twice a week, while it was 28 and 16 % in the similar light massage groups

At 24 weeks mean headache frequency was reduced 48 and 56 % in the SMT groups treated once or twice a week, while it was reduced 35 and 31 % in the similar light massage groups