* The adjusting head was supplied by Dr Jeffrey Blanchard, Del Mar, California, USA and the guidance apparatus (a modified milling machine) by Dr Burl Pettibon, Tacoma, Washington, USA.
The instrument was set to deliver a rapid volley of about 30 mechanical percussions, conducted through the stationary stylus, over a period of about 15 seconds. At the end of each visit, the subject rested supine on a padded bench for 15 minutes with the back of the neck cushioned comfortably on a polyurethane semi-cylindrical support, of about 10 cm diameter ("Chinese pillow") with legs bent and thighs and calves supported on several pillows.
A visual check of supine leg length was performed before and after each adjustment. Change from an apparent LLI to none was used to indicate a successful result. Usually, other indications were that the subject was able to move her head more freely on extension and left and right rotation. X-rays were retaken 10 minutes after the first adjustment.
Results and Ongoing Management
Measurements taken from the X-rays after the first adjustment indicated a reduction in TDZ of 2° (from 6° to 4°). After the first adjustment and lasting for 4 days until the following visit, the subject reported no tinnitus or otalgia. Further visits were recommended, and when 6 mm or greater LLI was found, an adjustment was given. At each visit the subject consulted her diary and reported on symptoms experienced since the previous visit. More often than not she would describe a reduction in severity, but also frequently noted residual neck pain on active right rotation. During the 5 months after the first adjustment, she made 23 visits at frequencies ranging from twice a week to twice a month, as recommended by the chiropractors. Thereafter, ,she made appointments whenever she thought she needed an adjustment, typically if right neck pain and other symptoms returned, or were not sufficiently relieved by home use of the "Chinese pillow." In the 7 - year period the subject visited the office on 217 occasions, was X-rayed 7 times and took 7 hearing tests.
No adjustment was given at 37 visits, because no LLI was found on examination. At 180 visits (83% of visits) an adjustment was given. Intervals between these adjustments varied from 1 to 71 days (mode 14, average 14.2). There were 16 intervals longer than 28 days (range 29-71), averaging 45.9 days of relief after an adjustment.
When several visits were made within 2 to 3 weeks, this indicated that the adjustment had provided only temporary or no relief. The worst period of response to adjustment was towards the end of 2000 (final 6-month period) when the subject reported a cluster of home, work and study stresses and received 25 adjustments in 26 weeks. Figure 2 shows the spread of visits and adjustments on a 6-monthly basis from the time of the first visit.
Apart from providing relief, adjustments also were observed to provoke the symptoms. This happened on 17 June 1994, when the subject reported only mild neck pain and no other symptoms. Within hours of the adjustment,. however, she wrote that "no amount of Disprin" could ease the severe neck pain, which "spread across the base of the skull" and was followed by a "blocked and painful" right ear and a "very sore" right jaw, as well as mid-thoracic pain, concentration difficulties and irritability. On another occasion 4 September 2000 a rapid exacerbation of tinnitus was reported after adjustment.
Using a mechanical adjustment device allows for more repeatable interventions than those done by hand. [36, 37] In 1971 the first author and Dr Kathleen Bras converted the adjusting-instrument method of Pettibon from vectored "toggle" of soft tissue near the atlas transverse process to vectored percussions of the temporal region of the head. 
Tapping the skull with vectored percussions has been reported to change craniovertebral angulations seen on X-rays,  and tapping it with a reflex hammer has been reported to activate vestibular reflexes.  For reasons covered above in the discussion on vectors, the presumed effect on craniovertebral angulations is thought to be the primary one in this case. For an overview of upper-cervical adjusting instruments, see K yneur and Bolton  and Grostic.  The TDZ x-ray analysis is based on the Pettibon analysis protocols for upper cervical spine X-rays, [22, 23] also referred to as upper cervical orthogonal (UCO) analysis.  An early study of reliability in intra- and inter-observer reliability for DCO x-ray measurements found it to be poor.  Two later studies [41, 42] found it to be very good for both atlas laterality and the lower angle and acceptable for atlas rotation. No studies have established the validity of DCO procedures, and they remain controversia1. [43, 44] The leg-length analysis indication used to indicate the need for an intervention is used widely within the chiropractic profession. 
The impact of these symptoms on this subject prior to the study period was substantial and appeared to be progressively increasing. The subject was planning a career change to try to cope with the impact of the disorder. Despite lack of a complete cure, the prolonged abatement of many hitherto intractable symptoms has been important to the patient. The psychological distress associated with Meniere's disease is generally accepted as an effect rather than a cause of the disorder  and may be severe. In one study of 19 sufferers whose symptoms, like this subject's, were resistant to dietary and medical therapies, depression scores were as high as for people with serious trauma and wellbeing scores were as low as for people with cancer. 
It is important to remember that controversy exists within the medical world regarding the appropriate management for Meniere's sufferers. Deafferentation surgery is usual in extreme cases,  yet even at this extreme end of the scale, where surgery is considered the only option left, significant numbers of subjects experience remissions within the 6-8 week period awaiting surgery. Like chronic neck pain, Meniere's disease continues to provide challenges because of its unclear definition, lack of definitive treatment and its multifactorial, intermittent and often extremely disabling nature. Because of this complexity, a global assessment of treatment results using both objective and subjective findings is appropriate,  and a clinical diary as used in this case report makes an important contribution to overall assessment. 
The patient reports on consistent sequences of symptoms are reminiscent of the patients whom Prosper Meniere praised 140 years ago as "good historians."  At that time, vertigo was thought to be a "cerebral trouble." Meniere wrote that his patients' reports oftheir vertigo being preceded by tinnitus had led him to believe that the inner ear was the site of their mysterious symptoms.  By comparison, this woman's extensive record-keeping helps demonstrate a link between Meniere's syndrome and the neck. Her experiences support the corollary also, that physical intervention to the neck by way of adjustment, can relieve symptoms of Meniere's syndrome.
Reviewers since 1977 have lamented the lack of progress in understanding this syndrome, [51-53] describing the situation as a "therapeutic imbroglio."  In the past, reviewers made dismissive reference to using the spine as a focus for Meniere's syndrome, either by traction,  or by manipulation,  however, the research community is not unanimous in its rejection of the musculoskeletal contribution to inner ear disorders such as Meniere's disease. [11, 12]
The lack of anatomical connection has been one objection to the association between the neck and ear symptoms. Recent research supports a neurologic connection. Shore et al.  note that the trigeminal nucleus is a major nucleus showing convergence of sensory input.  They demonstrated, using anterograde and retrograde tract tracing methods, that the auditory brainstem nuclei are connected with the trigeminal nucleus. Thus it is plausible that trauma to the cervical spine affects hearing and/or balance in some patients. It is also plausible to hypothesise that physical intervention to this region alters the course of conditions like Meniere's disease- even if temporarily. Weimama et ai. 55 postulated that pressure imbalance between the endolymphatic sac and intracranial space, aggravated when the cochlear aqueduct is blocked, may account for Meniere-like symptoms that were triggered by CSF leakage after spinal anaesthesia. The membranes in the cochlea and labyrinth have been demonstrated histologically at post mortem, but the amount of flllid necessary to produce the changes are minute-too little to measure in vivo (correspondence, R.M. Loane). This difficulty, along with the "exquisite sensitivity" to small changes that is said to be a feature of "dynamical diseases" such as Meniere's, [19, 56] may explain why such a puzzling variety of interventions are useful, but to different degrees in different subjects.
The fact that undertaking a lumbar puncture  or spinal anaesthesia  can both trigger Meniere's syndrome-like symptoms supports the idea of a relationship between this syndrome and the spine. A more direct connection may exist in the discovery of the so-called "myodural bridge" in the form of the rectus capitis posterior minor muscle attaching to the posterior atlanto-occipital membrane,  with an influence upon CSF flow. The clinical implications are only now being explored. [59-61] Clearly, anatomical evidence for a link between these structures is growing.
Watanabe et ai., using 20 subjects with confirmed Meniere's disease, plotted the severity of symptoms over a 243-day period. They, as in our case, note the association of stiff neck or shoulder with the exacerbation of ear symptoms, albeit with a 2-14 day latent period.  It appears that at least a subgroup of Meniere's disease sufferers may experience modulation of symptoms because of the cervical spine. Similar findings were had by Franz et al,  who found that 9 out of 45 subjects with vertigo and tinnitus also had upper cervical dysfunction, and of these one progressed to Meniere's syndrome. They proposed that a syndrome called "cervi co genic oto-ocular syndrome" might exist as a forerunner to Meniere's disease. Bjorne et al  also found that 75% of a group of 24 patients diagnosed with Meniere's disease reported a strong association with neck problems and triggered vertigo. Examination of the cervical spine for dysfunctions (such as muscle and joint tenderness and/or restrictions in movement) found them to be more common in Meniere's sufferers than in matched control subjects. At each exacerbation, our subject reported progression of symptoms from right lower neck pain to upper neck and then to the right ear. The history of neck trauma, most probably now associated with fibrosis, links these factors together. Other researchers have also noted this association as outlined above.
Filipo and Barbara  consider that over time Meniere's disease is characterised by four stages. Though the duration of each is unclear, the first prodromal stage is that in which anyone of the key symptoms is first experienced, but diagnosis remains unclear. Stage 2 is characterised by loss of balance and is the most disabling. Stage 3 develops as a stable period with less dizziness, and in Stage 4, the syndrome becomes bilateral. The hearing loss is either progressive or staged, usually without remissions in the level of loss.
The subject in this report has been followed for 7 years. This may be long enough for the advanced stages to have developed, and it is possible, in view of the reduced severity and duration of exacerbations, that this subject's deterioration has been delayed because of the adjustments. Four observations suggest that deterioration has been delayed: I) no episodes of vertigo were reported in the study period; 2) all four presenting ear symptoms were reported as briefer and milder than they had been in the pre-study period; 3) her worst audiometric indication of hearing loss in the study period, a pure tone average (PTA) of 25dB, was comparable with her pre-study losses and more like the Kinney et al  subjects' average baseline loss of 38.0 (1.22.1 SD) dB than their average long-term loss of 43.3 (1.22.0 SD) dB; and 4) her audiograms indicated continuing fluctuation, a common characteristic of the early stages of Meniere's disease. These findings suggest that chiropractic care may have retarded this subject's progression towards the more advanced stages of Meniere's disease.
In subjective reports, however in a long-term follow-up of Meniere's disease, Silverstein et al.  found only 50% correlation between subjective and objective hearing reports. However, some credibility in reporting hearing loss seems appropriate for this subject, specifically because 7 of her reports were corroborated by roughly contemporaneous audiograms and, more generally, because subjective reports of hearing difficulties, elicited by questionnaires, were judged rough but reasonable substitutes for audiometry in recent South Australian and British surveys of hearing loss. 
Range of motion assessments were variable in pre- and post- assessments. Only lateral flexion data is illustrated, because it is considered the most stable, and an observed change would be more likely to represent true change-more so than the other directions of movement. The measured changes were still quite variable, though the subject reported pre-adjustment a reduction in flexibility, and post-adjustment an increase in flexibility. The extent of this appears to be more one of perception-perhaps by way of when pain is produced. Looking at the graph, there seems to be far wider variation in the earlier period.
The subject's condition appears to be following the "normal" progression for Meniere's syndrome, albeit with less distress and periods of relative normality assisted substantially by chiropractic adjustments. We look forward to further similar case reports and perhaps prospective group studies of chiropractic care for persons who suffer such non-life-threatening, but debilitating, non-musculoskeletal conditions.