Kurt Schellhas

Disc Protrusion

    • Very uncommon
    • Radiating Arm pain
    • Orthopaedic and neurological signs
    • Sometimes need surgery

Annular Tear

    • Very common
    • Often asymptomatic
    • Refer pain
    • Hard to identify

Kurt Schellhas published in Spine 21 (3) 1996
*https://pubmed.ncbi.nlm.nih.gov/8742205/

Ten lifelong asymptomatic subjects and 10 nonlitigious chronic neck/head pain patients underwent discography at C3-C4 through C6-C7 after magnetic resonance imaging. Disc morphology and provoked responses were recorded at each level studied.

Results. Of 20 normal discs by magnetic resonance from the asymptomatic volunteers, 17 proved to have painless annular tears discographically. The average response per disc (N = 40) for this group was 2.42, compared to 5.2 (N = 40) for the neck pain group. In the pain patients, 11 discs appeared normal at magnetic resonance imaging, whereas 10 of these proved to have annular tears discographically. Two of these 10 proved concordantly painful with intensity ratings of at least 7/10. Discographically normal discs (N = 8) were never painful (both groups), whereas intensely painful discs all exhibited tears of both the inner and outer aspects of the annulus.

Conclusions. Significant cervical disc annular tears often escape magnetic resonance imaging detection, and magnetic resonance imaging cannot reliably identify the source(s) of cervical discogenic pain.

Sites of reported pain on discography

C3-C4

  • Mastoid, temple, jaw, TMJ, parietal, occiput, craniovertebral junction, neck, throat, upper back, trapezius muscle, tip of shoulder, upper extremity

C4-C5

  • Mastoid, TMJ, parietal, occiput, craniovertebral junction, neck, throat, trapezius muscle, shoulder, upper extremity, anterior chest, upper back.

C5-C6

  • Occiput, craniovertebral junction, neck, upper back, throat, tapezius muscle, shoulder, upper extremity, anterior chest.

C6-C7

  • Neck, upper back, scapula, shoulder, trapezius muscle, upper extremity, anterior chest.

Examination of nerve root levels

C5 (disc level C4/5)

  • Deltoid

C6 (disc level C5/6)

  • Extensor Carpi Radialis Longus

C7 (disc level C6/7)

  • Extensor Carpi Ulnaris Ref Gray’s anatomy 38th ed.

C8 (disc level C7/T1)

  • Flexor Digitorum Profundus

T1 (disc level T1/T2)

  • MCP joint flexion or abduction

Check nerve roots by testing at the wrist, especially extensor carpi radialis and ulnaris. C7 nerve root is most common.

If neck protrusion negates the weakness, this indicates a possible annular tear or other neck dysfunction. If C7 is involved, you should find that supinator and triceps are weak on the involved side. Test shoulder abduction in supination and extension to confirm weakness and negation by protrusion. Sustained superior to inferior challenge to TVPs should negate the weakness and this indicates the level of adjustment.

If protrusion does not negate weakness, probably not a neck problem or could be frank disc prolapse.