Background
Current concepts regarding the source of cervical and brachialgic pain rely upon the perceptions derived from anatomical and pathological studies amplified by postoperative outcomes and CAT / MRI scans.
In he Spinal Foundation we carried out a study to examine pain patterns elicited during aware state surgery and their correlation with conventional diagnostic precepts.
Study Design
A prospective study of “ambulatory” Spinal Probing and Discography with Endoscopic Cervical Disc Decompression (ECDD) or Laser Disc Decompression (LDD).
Patient Sample
Anterior Cervical Spinal Probing and Discography was performed on 68 patients with multi-level cervical disc disease. In 19 there was overlap or dyscordancy of symptoms requiring the use of Differential Discography and these were excluded from this study.
Outcome Measures
An analysis of the production of concordant pain compared to expected pain distribution. A comparison with clinical outcome following ECDD and LDD. A 50% or greater reduction in back AND leg pain and the Oswestry Disability score deemed the threshold for a good clinical impact (GCI).
Methods
Patients completed a questionnaire containing the Vernon Mior Disability Questionnaire and a Visual Analogue Pain Score prior to ECDD or LDD and a year thereafter.
A single level ECDD or LDD was selected by the production of concordant symptoms during Spinal Probing and Discography.
Results
The pain production arose at an unexpected / atypical level in 14 cases. Neck pain was reproduced from the anterior cervical structures in 17 patients. Leakage reproduced neck pain in 23 patients and trapezial pain in 17 and brachial pain in 12. Leakage was asymptomatic in 6 cases. Closed discography reproduced neck pain in 18 patients and trapezial pain in 15 and brachial pain in 13. Brachial symptoms were more commonly elicited with foraminal protrusions or leaks. A GCI was reported in 46/49 patients at 1 year.
Conclusions
Aware state Spinal Probing and Discography allows the definition of the cervical pain source. It demonstrates that in certain patients these leaks are pain provocative. ECDD or LDD produces satisfactory clinical outcomes. It also showed that the conventional method of clinical diagnosis combined with MRI scan derived assessment of the pathology was misguided in 19/68 patients referred to this Tertiary referral unit.
The findings from probing the anterior neck structures are summarised above. They show that the anterior structures can mimic referred neck and shoulder pain.
The insertion of a radiopaque dye in to the disc serves to outline the areas of degeneration within the disc. It also produces pressure upon yje inside of the wall of the disc and this in turn may cause pain to arise from the disc wall or displaced irritated nerves.
However the distribution of the evoked pain is far wider than is normally supposed. The overlapping of such symptoms and their unexpected non-dermatomal distribution may lead to mis-diagnosis when convnetional teachings and the results of MRI scans are relied upon.
High Intensity Zones or leaking discs may produce explosive or widespread symptoms depending upon their position in the annulus or the direction of their drainage.
Currently such features are dismissed by conventional physicians but respected by those who utilise aware state feed back to localise the source of the cervical or neck pain. The pain may spread in to the shoulders and produce significant symptoms in the arms. These may present as coldness, scalding, vascular mottling or vascular spasm, formication, pain or spasm in part or wole of one or both limbs.
Such dysaesthesia is often dismissed as malingering especially where this is involved in post-traumatic litigation.
The effects of protrusions may be summarised as above but C4/5 and C5/6 pathology may be particularly misleading
The results of years of aware state studies may be summarised as above. MBP is Muscle Balance Physiotherapy
These pathologies may be treated by Cervical laser Disc Decompression or by Endoscopic Cervical Intradiscal Discectomy or Cervical Nucleoplasty.
