636 POSTGRADUATE MEDICAL JOURNAL December I950

up by interview, are summarized. Because of theabsence of a death rate this type of injection is

recommended as the radical treatment to be triedfirst.

BIBLIOGRAPHY(Letters in parentheses refer to Table 2)

ADAMS, W. E., and ROBINSON, R. (I94I), Lancet, ii, 555.ANONYMOUS (1923), Brit. J. Surg., 10, 573.BORSOTTI, I. (i938), Riv. oto-neuro-oftalm., I5, 408.CAMPBELL, A. M. G. (1948), Lancet, 1, 690.CARMICHAEL, E. A., and WOOLLARD, H. H. (I933), Brain,

56, 109.CAVINA, C. (I932), Riv. ital. Stomatol., I, 3.COENEN, H. (1932), Zbl. Chir., 59, 2963.COHEN, I. (1934), irch. Neurol. Psychiat., Chicago, 31, 2 1.(a) CUSHING, H. W. (192oa), Amer. J7. med. Sci., I6o, I57.(b) CUSHING, H. W. (I92ob), J. Amer. med. Ass., 75, 441.(c) DANDY, W. E. (I929), Arch. Surg., Chicago, I8, 687.(d) DANDY, W. E. (I932), Ann. Surg., 96, 787.DANDY, W. E. (Q934), Amer. J7. Surg., 24, 447.(e) FALCONER, M. A. (i949), J. Neurol. Neurosurg. Psychiat.,

12, 297.FERNER, H. (I949), Nervenarzt, 20, 26.(f) FRAZIER, C. H. (I925), Arch. Neurol. Psychiat., Chicago, 13,

378.(g) FRAZIER, C. H. (I93I), J7. Amer. med. Ass., 96, 9x3.FRAZIER, C. H., and GARDNER, W. J. (1928), Surg. Gynec.

Obstet., 47, 73.GLASER, M. A. (1928), Arch. Neurol. Psychiat., Chicago, 20, 537.(h) GRANT, F. C. (X938), Ann. Surg., 107, 14.(i) GRANT, F. C. (I943), Res. Pubi. Ass. nerv. ment. Dis., 23, 408.(j) GRANT, F. C. (1948), Amer. J. Surg., 75, 42.GUTNIKOFF, B. (I925), Arch. klin. Chir., 135, 79.HAERTEL, F. F. (i935), Dtsch. med. Wschr., 6i, 0o69.HARRIS, W. (1920), Proc. R. Soc. Med., 13, Parts i and 2, Clinical

Section, 62.HARRIS, W. (1936), Brit. med. J7., i, 457.HARRIS, W. (194oa), Lancet, ii, 481.HARRIS, W. (194ob), Brain, 63, 209.HEAD, H. (IgIo), 'Allbutt and Rolleston's System of Medicine,'

2nd edition, London, Macmillan, 7, 540.(k) HORRAX, G., and POPPEN, J. L. (1935), Surg. Gynec. Obstet.,

6I, 394.HUTCHINSON, J. (x9o5), 'The surgical treatment of facial

neuralgia,' London, John Bale and Danielsson.

JAENSCH, C. (1926)X Klin. Mbl. Augenheilk., 77, 212.JEFFERSON, G. (I93i), Brit. med. J., ii, 879.KIRSCHNER, M. (I933), Arch. klin. Chir., I76, 58I.KIRSCHNER, M. (1936), Ibid., x86, 325.(1) KIRSCHNER, M. (1942), Munch. med. Wschr., 89, 235, 263.KLUGE, A. (I922), Z. ges. Neurol. Psychiat. (Originalien), 76, 372.KOENNECKE, W. (I917), Dtsch. Z. Chir., I40, 225.KRAYENBUEHL, H. (1936), Brain, 59, 337.LEWY, F. H., and GRANT F. C. (1938), Arch. Neurol. Psychiat.,

Chicago, 40, 1126.McAULIFFE, G. W., GOODELL, H., and WOLFF, H. G.

(1943), Res. Pubi. Ass. nerv. ment. Dis., 23, i85.MORRIS, L. (1931), Lamcet, i, 122.NEUGEBAUER, F. (I9I8), Zbl. Chir., 45, 565.(m) ODDSSON, B. (i944), Acta Psychiat., Kbh., 19, 293.(n) OLIVECRONA, H. (1942), Arch. Neurol. Psychiat., Chicago,

47, 5 t4.(o) OLIVECRONA, H. (I947), Acta Psychiat., Kbh., Suppl. 46,

268.(p) PANNABECKER, C. L. (i944), Arch. Ophthal., N. Y., 32, 456.PENMAN, J. (I949), Lancet, ii, 268.PENMAN, J., and SMITH, M. C. (I950), J. Neurol. Neurosurg.

Psychiat., 13, 36.PUTNAM, T. I., and HAMPTON, A. 0. (1936), Arch. Neurol.

Psychiat., Chicago, 35, 92.(q) RANEY, R., RANEY, A. A., and HUNTER, C. R. (1948),

Trans. Amer. neurol. Ass., 73, 148.REVILLA, A. G. (1946), J. Neurosurg., 4, 233.SICARD, J.-A. (19I8), Med. Pr., zo6, 6o.SJOEQVIST, 0. (I937), Zbl. Neurochir., 2, 274.SJOEQVIST, 0. (1938), Acta Psychiat., Kbh., Szeppl. 17.SJOEQVIST, 0. (I939), Acta chir. scand., 82, 201.TAPTAS, N. (I93I), Pr. mid., 39, 239.TROUSSEAU, A. (I86I), 'Clinique m6dicale de F'H6tel-Dieu de

Paris,' ist edition, vol. 2, Paris, Bailli6re. Translated in Publ.New Sydenham Soc., I868, 35, 105.

WEISENBURG, T. H. (I90o), _. Amer. med. Ass., 54, i6oo.ZANDER, P. (1933), Arch. klin. Chir., 178, 242.(r) ZENKER, R. (934), Med. Welt, 8, 14.(s) ZENKER, R. (1938), Ergebn. Chir. Orthop., 31, 1.

CERVICAL INTERVERTEBRAL DISC PROTRUSIONBy VALENTINE LOGUE, M.R.C.P., F.R.C.S.

Assistant Neurological Surgeon to St. George's Hospital and the Maida Vale Hospital for Nervous Diseases. NeurologicalSurgeon to the Royal National Orthopaedic Hospital

The prolapsed intervertebral disc in the lumbarregion which compresses a nerve root to producesciatica has become, since its original descriptionin I934, a commonplace in diagnosis, with itsmethods of conservative and surgical treatmentfirmly established, and it seemed only a question oftime before the symptomatology of prolapsed discselsewhere in the spinal column was recognized. Inthe case of the cervical region however this recog-nition was somewhat tardy. The first detaileddescription to be published in an English journalof lateral protrusions causing brachial neuritisappeared only five years ago', and the various syn-dromes of spinal cord compression from medianprotrusions and their tendency to mimic degenera-tive diseases of the cord, although first described in1928, are even at the present time not widely known.

It is possible for a cervicat protrusion, dependingon its relationship to the nervous structures, toproduce three different syndromes, which are

illustrated in Fig. i and which were first describedby Stookey :2

i. A lateral protrusion causing pressure on anerve root to produce brachial neuritis.

2. A more medial protrusion compressing onehalf of the spinal cord with a Brown-Sdquardsyndrome.

3. Midline protrusion causing bilateral spinalcord compression.

Occasionally a prolapse may start with symptomsof root compression and then increase in size andproduce successively unilateral and then bilateralcord involvement.

I. Lateral Protrusion with Nerve RootCompression

AnatomyThere are only six intervertebral discs in the

by copyright. on M

arch 28, 2020 by guest. Protected

http://pmj.bm

j.com/

Postgrad M

ed J: first published as 10.1136/pgmj.26.302.636 on 1 D

ecember 1950. D

ownloaded from

LOGUE: Cervical Intervertebral Disc Protruision

FIG. I

A. Midline protrusion causing pressure on both halvesof the spinal cord.

B. Protrusion occurring to one side of the midline,causing pressure only on one half of the spinal cord.

C. Lateral protrusion compressing the nerve root withno involvement of the cord.

cervical region (there being none between the occi-put and atlas, or between atlas and axis), the first ly-ing between the axis and the third vertebra and thesixth between the seventh cervical and first thoracicvertebrae. (To simplify de3cription the disc levelwill be referred to by nominating the vertebraebetween which it lie-, thus the Cs-6 and C6-7discs, which involve the sixth and seventh cervicalnerve roots respectively.)The discs with the greatest mobility and there-

fore most prone to injury and degeneration arethose between vertebrae C5-6 and C6-7, and aswould be expected these are the common sites forprolapse. Protrusion may also take place, but in-frequently, from the C4-s and C7-Di discs, andvery occasionally at the C3-4 and CZ-3 levels. Thesize of an intervertebral disc in the lower cervicalregion is much less than in the correspondingportion of the lumbar spine (about one-eighth thesize) and the protrusion is smaller in bulk, butowing to its closer relationship to the nerve rootand the smaller intervertebral foramen, symptomsare as readily produced, although the transversecourse taken by the cervical nerves makes it im-possible for a lateral prolapse to compress morethan one root.

AetiologyTrauma plays a much smaller part in cervical

than in lumbar disc lesions. Occasionally inyounger people there is a history of an automobileaccident, a dive into shallow water or a severe blowon the head, but as a general rule no single in-cident can be blamed. The condition commonlyarises from degeneration of the intervertebralcartilage in men between the ages of 30 and 50,with the actual prolapse occurring from a suddenmovement of the head or arm, or on coughing, oreven during sleep. Its frequency, compared tolumbar prolapse, is about one to eight.

SymptomatologyFollowing a history of repeated attacks of stiff

neck or without any previous local symptoms, thereis the gradual development of the predominatingsymptom-pain, which is felt just to one side of thebase of the neck, in the supraspinous fossa and overthe point of the shoulder, and which in the courseof a few days radiates down the arm. Its precisedistribution in the arm varies with the individualroot affected. In compression of the sixth root(Cs-6 disc) the pain is felt in the anterior axillaryfold, the antero-lateral aspect of the arm as far asthe elbow and along the radial side of the forearmup to, but not as a rule beyond, the wrist. In thecase of the seventh root (C6-7 disc) it radiatesdown the posterior axillary fold, the postero-lateral part of the arm and the dorsum of the fore-

637December 1950by copyright.

on March 28, 2020 by guest. P

rotectedhttp://pm

j.bmj.com

/P

ostgrad Med J: first published as 10.1136/pgm

j.26.302.636 on 1 Decem

ber 1950. Dow

nloaded from

638 POSTGRADUATE MEDICAL JOURNAL December 1950

A. B.

C. D.FIG. 2.-To show the distribution of pain (lined areas) and the sensory change (stippling) in cervical nerve

root compression. The density of the stippling indicates the frequency with which sensory change occurs.A = 5th, B = 6th, C = 7th and D = 8th root compression.

arm as far as the wrist. The pain may be felt as acontinuous band down the arm or localized inareas of maximum intensity, particularly in thedeltoid muscle or in the elbow joint or wrist. Ithas a severe aching character, often preventingsleep and is made worse by use and exercise of thearm, certain moverments of the neck, coughing,sneezing, straining and jolting. The patient mayfind that by elevating and abducting the arm, orflexing the head and inclining it away from theaffected side, some relief may be obtained, andlearns to adopt this position in a chair or in bed inorder to get rest. Occasionally, as well as beingfelt in the arm, the pain radiates into the pectoralismajor and the praecordium, with a sensation ofconstriction of the chest and difficulty in breathing,and when this occurs on the left side it may simu-late coronary thrombosis. In other patients thepain may extend up to the occiput or even into theorbit and behind the eye. The areas in which pain

is felt in sixth and seventh root compressions andalso in the less commonly affected cervical roots,is shown in Fig. 2.

Paraesthesiae, often extremely unpleasant andvariously described as tingling, burning, or as apins and needles sensation, are felt towards theperiphery of the pain distribution, being maximalin the hand and fingers. With sixth root com-pression paraesthesiae are felt mainly in the baseof the thumb, the first interosseous space andradial aspect of the forearm. In the case of theseventh root the areas affected are the back of thehand and the index and middle fingers, with lesscommonly an extension to the ring finger or thethumb, but occasionally the tips of all the fingersmay be involved. This variation in the distribu-tion of the paraesthesiae in individual roots is dueto the wide overlap of adjacent nerve segments..Numbness may develop in parts of the para-

esthetic areas and when it involves the fingers it

by copyright. on M

arch 28, 2020 by guest. Protected

http://pmj.bm

j.com/

Postgrad M

ed J: first published as 10.1136/pgmj.26.302.636 on 1 D

ecember 1950. D

ownloaded from

LOGUE: Cervical Intervertebral Disc Protrusion

often causes difficulty in the manipulation of smallobjects. There is rarely any complaint from thepatient of weakness in the arm and any disinclina-tion to use it is mainly due to pain.

On examinationIt will be found that the neck is held stiffly,

sometimes tilted to the opposite side and, despite afull range, the movements are performed slowlyand flexion to the affected side may increase thepain down the arm. A reliable test in the acutestage is that of ' neck compression' described bySpurling,3 which consists of applying pressuredownwards on the head when it is rotated and in-clined towards the affected shoulder and whichresults in a sharp exacerbation of typical pain, theonset of which may be delayed for a few seconds.Conversely, traction on the head with the handsunder the chin and occiput will relieve the pain.

Muscle tenderness is often present, particularlyin the supraspinatus, pectoralis major, deltoid andextensors of the wrist, either diffusely or in local-ized ' fibrositic' areas, pressure on which will re-produce the pain and, as in the case of similarnodules in the lumbar region with sciatica, tem-porary relief may be obtained by local injectionwith procaine.The changes in the motor system will vary with

the nerve root involved. Thus with sixth rootcompression the muscles usually affected are thedeltoid and biceps which exhibit a flabbiness andloss of tone, and in the more severe cases actualwasting with some degree of weakness. The bicepsjerk is reduced or absent. In the case of theseventh root similar changes occur in the tricepsand the extensors of the wrist and fingers withdiminution of the triceps jerk, the biceps andsupinator reflexes being unaffected.

There is often no objective alteration in sensa-tion despite intense paraesthesiae and when it ispresent is not as a rule very severe. Sensorychange is usually maximal over the fingers, butmay extend proximally into the hand and fore-arm. The typical changes are illustrated in Fig. 2.It will be seen that sixth root involvement pro-duces diminution to touch, pain and thermalstimuli over the first interosseous space and thebase and dorsal aspect of the thumb, whereas withseventh root compression the terminal phalanx ofthe index finger is characteristically affected with alesser change over the rest of the index finger, withoften an extension to include the middle finger andthe tip of the thumb. In some patients the index,middle and ring fingers are affected. There isusually no change detectable in deep sensation.The more typical features of compression of thesixth and seventh cervical roots may now besummed up:

FIG. 3.-A lateral radiograph to show obliteration of thenormal cervical lordosis and narrowing of theC5-6 intervertebral disc space with lipping of theadjacent vertebral bodies.

Sixth root. Pain at the base of the neck, supra-spinous fossa, anterior axillary fold, antero-lateralaspect of the arm and radial side of the forearm.Wasting of the deltoid and biceps muscles, withreduced biceps jerk. Sensory change over thebase and dorsal aspect of the thumb and first in-terosseous space, sometimes extending to theradial side of the forearm.

Seventh root. Pain in the base of the neck andsupraspinous fossa radiating down the posterioraxillary fold, postero-lateral surface of the arm anddorsal aspect of the forearm. Wasting and weak-ness of the triceps and extensors of the wrist, withreduced triceps jerk. Sensory change typically inthe index and middle finger, often the tip of thethumb.

It must be emphasized, however, that owing tothe variation in pre- or post-fixation of the cervicalplexus, the localizing value of these signs is not byany means absolute, and not infrequently forexample i; may be found that the characteristicfeatures of a seventh root compression are as-sociated with a prolapse demonstrated by myelo-graphy or at operation to be at a higher level(C5-6).

Protrusion of discs at other levels in the cervicalspine produces pain and paraesthesiae, motor andsensory changes of similar character, which differmerely in their distribution. Prolapse of the C2-3disc involving the third cervical root has onlyrarely been reported and one of the best descrip-

December 1950 639by copyright.

on March 28, 2020 by guest. P

rotectedhttp://pm

j.bmj.com

/P

ostgrad Med J: first published as 10.1136/pgm

j.26.302.636 on 1 Decem

ber 1950. Dow

nloaded from

POSTGRADUATE MEDICAL JOURNAL

FIG. 4.-The myelogram in a case of lateral protrusionof the C5-6 disc on the right side to show the ovalindentation in the column of contrast oil.

tions of such a condition, which was confirmed atautopsy, is that given by Young. In this case thepain was felt down the right side of the neck. Thetongue was elevated on the affected side anddifficult to manipulate owing to lack of fixation ofthe hyoid bone from weakness of the infrahyoidmuscles. Pressure on the fourth root by C3-4 pro-lapse produces pain in the side of the neck extend-ing to the clavicle, tip of the shoulder and supra-spinous fossa. C4-5 prolapse will cause pain in theneck and top of the shoulder, extending down theouter side of the deltoid and arm to the elbow,often with weakness and wasting of the supra-spinatus and deltoid, and sensory change over theouter aspect of the arm. C7-DI protrusion withcompression of C8 root produces pain in the neckand supraspinous fossa radiating down the inneraspect of the axilla and inner side of the forearmand hand, with hypalgesia particularly of the ringfinger, and some weakness of the intrinsic musclesof the hand, a clinical picture often erroneouslyattributed in the past to a 'scalenus anticus syn-drome.'

InvestigationsRadiography. Plain X-rays of the neck may

demonstrate no abnormality, but the usual changeis some flattening of the cervical lordosis withoutscoliosis, and a narrowing of the relevant disc

space with lipping of the adjacent vertebrae (Fig.3). These changes, however, are not infrequentlyseen in middle-aged people without symptoms ofroot compression and therefore cannot be reliedupon as being conclusive of prolapse, but aresuggestive when taken in conjunction with theclinical features.

Myelography. The diagnosis of brachial neuritisdue to a cervical disc lesion is essentially a clinicalone and there is as a rule no need for confirmationby myelography unless there is the question of aspinal neoplasm. When, however, surgical removalis contemplated myelcgraphy is an importantpreliminary, not only to confirm the diagnosis butaccurately to localize the level, and for this it is amore reliable investigation than in the case oflumbar protrusions. The typical appearances seenin a lateral prolapse consist of (i) in small disclesions merely a lack of filling of the root sheathand (2) in the larger protrusions an oval or tri-angular indentation in the side of the column ofcontrast medium, as well as obliteration of the rootsheath (Fig. 4).

TreatmentThere is in this condition, to a greater degree

than is the case in sciatica, a spontaneous tendencytowards recovery, so that the early treatment isalways conservative and its chances of success aregreat, most cases being pain free in six to eightweeks. Rest in bed is the basis of treatment, thepatient usually being more comfortable proppedup with the arm supported. In the more severecases traction on the head with a neck sling, usinga weight of 8 to io lb., often has a dramatic effectin relieving pain. It need not be constantly ap-plied, but can be put on during the day and dis-continued at night, and the extent to which it isused will depend on the relief it produces and thepowers of tolerance of the patient. If traction isto have any effect it will be noticeable within thefirst two to three days and it is then continued forthree to four weeks. After this the patient isallowed up and wears a moulded plastic or leathercollar which should be continued for three monthsand then gradually discarded. In less severe casesand particularly in patients who, for one reason oranother, wish to remain ambulant, it is oftenpossible to relieve the pain by keeping the armabducted and elevated, either on an aeroplanesplint or more satisfactorily on an abductionplaster, which probably act by relieving tensionon the nerve roots. This is retained for four tosix weeks and should be followed by the wearing ofa collar.

Manipulation of the neck is sometimes em-ployed and may help some patients, but it oftenmakes the symptoms worse and it carries the

640 December 1950by copyright.

on March 28, 2020 by guest. P

rotectedhttp://pm

j.bmj.com

/P

ostgrad Med J: first published as 10.1136/pgm

j.26.302.636 on 1 Decem

ber 1950. Dow

nloaded from

LOGUE: Cervical Intervertebral Disc Protrusion

potential danger of producing a further protrusionof the disc against the spinal cord, with disastrousresults.

Operative TreatmentThe indications for surgery in nerve root com-

pression are as follows:(a) Development of signs of spinal cord involve-

ment.(b) Severe pain persisting despite an adequate

trial of conservative methods.(c) Persistent symptoms, which although not

severe, prevent the patient from working over along period.

(d) Recurring attacks of pain at frequent inter-vals.

(e) Severe sensory change in the fingers.The indications under Groups (a), (b) and (c)

require no comment. In Group (d) no definiterule can be laid down, for it will depend mainly onthe patient's tolerance, but I have found that mostcases who have had three attacks within i8 monthsto two years want something more permanent inthe way of relief. In Group (e) although the painmay no longer be an important feature, operativeremoval may occasionally be required for certainpeople, such as musicians, who require perfectsensation in their fingers. I recently had a case ofa cartographer who was left with a numb indexfinger and thumb tip from a C7 root compressionand as a result was unable to manipulate the finepen used in map making. After removal of theprotrusion sensation improved and he was able toresume his occupation.

Operative TechniqueThe sitting position is probably the best for this

operation, but due recognition must be given to itsoccasional dangers.As there is no local anatomical landmark in the

lower cervical region to guide one, such as thefirst piece of the sacrum in lumbar operations, it isbest to make a fairly long midline incision from theaxis to the spine of C7 and then to count thevertebrae down from the large and umistakablespinous process of the axis. A unilateral separationof the muscles from the bone is then made, therelevant interspace exposed, and the adjacentmargins of the laminae above and below nibbledaway. This opening can be extended laterally byremoving the margin of the facet with a dentalchisel. The ligamentum flavum is cut away to re-veal the nerve root kinked backwards by the pro-trusion, which is rarely more than 5 mm. indiameter and more often the size of a match head.As soon as the annulus is incised separated portionsof cartilage may extrude in a manner similar toprotrusions in the lumbar region and removal is

simple, but sometimes the prolapse is of bonyhardness and will have to be chiselled away. . It isnot necessary to curette the remainder of the disc.The results following surgical removal are as

good as in the case of lumbar discs, the painusually disappearing immediately after operation,but paraesthesiae may persist for one or two weeksif the root has been too firmly retracted. Thechances of recurrence are slightly less than forlumbar protrusions.

2. Spinal Cord CompressionThe recognition of cervical prolapsed discs first

came about because of the syndromes of spinalcord involvement which they produced, and theearlier literature is concerned entirely with theireffect on the cord (although the protrusions werecartilage), and it is only in recent years that theirthought at first to be chondromata arising from theimportance as a cause of root compression hasbecome known. The proportion of cord to rootcompressions is about one to five. As describedearlier (Fig. i), if the protrusion arises to one sideof the midline it will tend to compress one half ofthe spinal cord, producing a partial Brown-Sdquard syndrome, and if it arises in the midlineit will produce bDilateral cord compression.

Unilateral Cord CompressionThe evidence of unilateral compression of the

spinal cord is shown in its most typical form bysigns (i) in the arm of root compression, par-ticularly of atrophy and fibrillation in the musclesinnervated by it, and with or without root pain, (2)of pyramidal tract involvement in the lower limbon the same side as the affected arm, and (3) ofspinothalamic tract disturbance in the trunk andleg on the opposite side. Tactile sensation may beslightly impaired but joint, muscle, position andvibration sense are characteristically spared. Thereis no alteration of sphincter control. In sharp dis-tinction from the laterally placed discs causingbrachial neuritis, there are often no symptoms orsigns referable to the neck.

This particular type of partial Brown-S6quardphenomenon showing such precise and selectiveinvolvement of the spinal cord is highly charac-teristic of unilateral disc compression, the onlyother lesion likely to produce a comparable picturebeing a small meningioma growing in a similarsituation to the protrusion.

Owing, however, to the dissociated character ofthe sensory loss it may appear to those unfamiliarwith this syndrome, that the condition is one of anintramedullary lesion of the cord, such as a gliomaor degenerative disease, and much valuable timemay be lost before the correct conclusion is arrived

Deocember I950 641by copyright.

on March 28, 2020 by guest. P

rotectedhttp://pm

j.bmj.com

/P

ostgrad Med J: first published as 10.1136/pgm

j.26.302.636 on 1 Decem

ber 1950. Dow

nloaded from

POSTGRADUATE MEDICAL JOURNAL

at, during which irreparable damage occurs to thecord.The diagnostic difficulties are further increased

by the fact that the manometrics of the spinal fluidfrequently show no evidence of block and the pro-tein content of the c.s.f. shows little or no increase.

Variations of this typical clinical picturecommonly occur and add to the diagnostic prob-lem. In some cases there may be spasticity withincreased reflexes in the affected upper limb, withno evidence of atrophy or fasciculation, and thisspasticity may involve muscles innervated fromcord segments higher than that of the compressedlevel, a phenomenon which is still unexplained. Inother cases there may be no symptoms or signs inthe upper limb referable to the nerve root at thelevel of the compression and the patient presentssolely with spasticity in one leg and spinothalamicchanges in the opposite half of the trunk and leg.The changes in sensation may also vary. The

upper level of pain and temperature loss is alwaysseveral segments (never less than four) below thelevel of compression, as might be expected fromthe knowledge of the oblique course taken by thecrossing spinothalamic fibres, but what is moreimportant is that it may be a considerable distancebelow the compression, on the lower abdomen orthigh, and even then it tends to have a sharplydemarcated upper border rather than a fadingedge of hypalgesia. It can be seen that in apatient exhibiting a well-defined level of pain andtemperature loss low on the trunk on one side, withpyramidal involvement in the opposite leg andwith no symptoms referable to the neck or arms,that attention will tend to be focused on thethoracic portion of the spinal cord, and it is only afamiliarity with these varied syndromes of cervicaldisc protrusion which will suggest a careful myelo-graphic screening of the cervical portion of thespine if the thoracic region is found to be normal.Some of these features are shown by the follow-

ing case:Case i. A lady of 38 years. Six months before

admission she noticed a heaviness and stiffness inthe right arm with impairment of fine movementin the fingers. One month later stiffness appearedin the right leg and she caught her toes whenwalking. Three weeks after this she developed aburning sensation in the left side of her chest witha feeling of pins and needles in the left calf, andshe noticed she could not feel the difference be-tween hot and cold water with the left leg. Therewas no sphincter disturbance. These symptomshad tended steadily to get worse, but for a fort-night before admission there had been a littleimprovement.On examination there was a full range of neck

movement without pain or local tenderness.

There was no wasting or fasciculation in theupper limbs. The right arm showed generalizedweakness with considerable spasticity, exaggeratedreflexes and a Hoffman's sign. The right legwas even more spastic with ankle and patellarclonus, exaggerated reflexes and a brisk extensorplantar response. The abdominal reflexes wereabsent on the right. On the left side of the trunkat the fifth thoracic dermatome there was asharply defined level of hyperalgesia below whichthere was analgesia to pain and thermal stimuli.This sensory change extended down to cover thewhole of the left leg. Tactile sensibility wasaffected to a much slighter and more variabledegree over this area. There was no involvementwhatsoever of joint, position or vibration sense inany limb.X-rays showed narrowing of the C5-6 disc space

with osteophytic lipping.Myelography revealed a partial block extending

from the lower border of the sixth to the lowerborder of the third cervical vertebrae, the contrastmedium tending to flow slowly along either sideof the dural sac. The appearances were suggestiveof an intramedullary tumour.At operation a prolapse from the C5-6 disc

measuring i cm. across was found lying to theright of the midline and the loose cartilage was re-moved. There was a small area of degenerationabout 2 mm. in diameter in the overlying cord.

This case illustrates many of the features;spasticity in the arm without pain, muscle wastingor fibrillation, and spasticity in the leg, with painand temperature loss on the opposite side of thebody, having a sharp upper margin seven seg-ments lower than the level of compression, andwith no involvement of vibration, joint and positionsense, or of the sphincters.

It is a strange fact that a small protrusion intothe spinal canal, usually less than i cm. across,which is not ' compressing' the cord in the usualsense of the term but merely indenting it, shouldproduce such localized and severe damage, whichis evident on clinical examination by the severityof the long tract disturbances, and at operation bythe degeneration to be seen in the substance ofthe cord. This may appear as a soft, whiteatrophic area or a grey translucency, indicative ofactual destruction and absorption of the nervefibres, which is a degree of degeneration that israrely seen even with the gross distortion producedby the larger meningiomas or neurofibromas.These changes would appear to be due to twofactors, one is the physical hardness of the pro-lapse, much harder than any of the commontumours presenting in the spinal canal and thesecond, the fact that the spinal cord is securelytethered by the dural sheaths of the nerve roots

642 December 1950by copyright.

on March 28, 2020 by guest. P

rotectedhttp://pm

j.bmj.com

/P

ostgrad Med J: first published as 10.1136/pgm

j.26.302.636 on 1 Decem

ber 1950. Dow

nloaded from

LOGUE: Cervical Intervertebral Disc Protrusion

and the ligamenta denticulata, so that it cannotmove backwards away from the protrusion and anymovement of the neck, particularly flexion, pullsthe cord firmly across the surface of the disc andthis repeated friction produces the damage.

Bilateral Cord CompressionBilateral cord compression from a midline disc

typically manifests itself by signs in the trunk andlegs of involvement (i) of both pyramidal tractsand (2) of both spinothalamic tracts, with (3) tac-tile sensibility affected either slightly or not at all,and joint, position and vibration sense andsphincter control being completely spared. Charac-teristically there are no symptoms referable to theneck. The changes which occur in the upperlimbs are variable, in some cases there is sub-jective numbness down the inner borders of theforearm and hand, usually not referable to thenerve root at the level of the compression, andoften associated with hypalgesia in this area with alittle wasting and weakness of the intrinsic musclesof the hand. In other cases there may be spasticityof the arms with exaggerated reflexes and a Hoff-man's sign, and not infrequently there may be nochanges in the upper limbs at all.There is a tendency for the symptoms and signs

to vary in severity, particularly if the patient isconfined to bed, when it may be found that thelegs become less spastic and the level of sensorychange may fall many segments.These are the typical manifestations of the con-

dition but a more important syndrome from thediagnostic point of view, which has been em-phasized by Bucy,-5 consists solely of bilateralmotor involvement in the legs with a disturbanceof gait and balance and with no sensory changeswhatsoever. The spasticity tends to be out of allproportion to the weakness, and the patient maynotice that a spontaneous clonus appears in thelegs when sitting down or driving a car. The in-terference with balance causes the patient to walkon a wide base and to turn slowly, without how-ever any ataxia in the heel/knee/shin test beingdemonstrable. All modalities of sensation are un-affected and there is no interference with sphinctercontrol. It can be appreciated that such a syn-drome with its main effect on the motor systemcan easily be mis-diagnosed as disseminatedsclerosis, or if root prcs3ure signs of wasting ofthe intrinsic hand muscles also occur, asamyotrophic lateral sclerosis.The diagnosis is rendered even more difficult by

the fact that the term' compression' of the spinalcord has come to be associated exclusively withthe changes seen in the presence of a large spinaltumour, particularly a block on Queckenstedt's

ProteinCase Type of Manometry ContentNo. Compression of C.S.F.

Per cent.I Unilateral Partial block 8o mgm.2 Bilateral No block 50 mgm.3 Unilateral No block 45 mgm.4 Unilateral No block 45 mgm.5 Bilateral Partial block 40 mgm.6 Bilateral No block 35 mgm.7 Unilateral No block 25 mgm.8 Bilateral No block 20 mgm.9 Bilateral No block 20 mgm.IO Bilateral No block 20 mgm.

FIG. 5.-A summary of the findings in ten cases ofcervical disc protrusion producing uni- orbilateral cord compression.

FIG. 6.-The myelogram in Case (2), showing the partialblock extending from the upper border of the fourthto the lower border of the sixth cervical vertebrawith a thin incomplete column of opaque mediumall round the sides of the obstruction.

test, xanthochromia and a high protein in thec.s.f., and the belief still lingers that in cases whereno block can be demonstrated by manometry amyelogram will not be informative. The con-verse, however, is true in cervical disc protrusionscausing bilateral (and unilateral) cord com-pressions; there is usually no block or at most-a

December 1950 643by copyright.

on March 28, 2020 by guest. P

rotectedhttp://pm

j.bmj.com

/P

ostgrad Med J: first published as 10.1136/pgm

j.26.302.636 on 1 Decem

ber 1950. Dow

nloaded from

POSTGRADUATE MEDICAL JOURNAL December I950

.......

...~~~~~.....::.. ...... .......... ^ , , .

.....-

*.. ........ .>R. .... .. ..-i*::::::j..'>eE:. -.X....°.'. .....* ; 1!m l ll li,. ........::::::::::!:i!--.r-.:̂.....................,jl||lll....

FIG. 7 (after Kahn).-To show the lines of stress (dotted lines) at and behind theattachment of the dentate ligaments..

partial block on manometry, there is no xantho-chromia in the fluid and the increase in proteinis small or absent. Fig. 5 illustrates the findings inten cases of median disc protrusions, causing uni-lateral or bilateral cord compression. It will beseen that no less than eight cases showed no blockand the protein content was normal in six cases(taking 40 mgm. per cent. as the upper limit ofnormal).The following case illustrates many of the

diagnostic features:Case 2. A man aged 37. Four months prior to

admission he slipped and fell heavily on to hisbuttocks, but did not directly injure his head orneck. Two weeks later he developed numbness inthe fourth and fifth fingers of both hands. Twelveweeks before admission he noticed stiffness of bothlegs and an unsteadiness in walking and dis-turbance of balance particularly on turning quickly,and there was also a sensation of woolliness underthe soles of both feet. There were no symptomsreferable to his neck. He was admitted at that

time to a neurological department where a lumbarpuncture was performed, which showed no evi-dence of block, and a protein of 50 mgm. per cent.in the c.s.f. A diagnosis of disseminated sclerosiswas made and he was discharged. Two weekslater he began to feel a tightness across the frontof his thighs and also developed some urgency ofmicturition.

Examination on Admission. Movements of theneck were unrestricted and painless. There was alittle wasting of the interossei of the left hand andthe fingers assumed the main-en-griffe position.The reflexes in both arms were exaggerated.There was a mild diminution to all forms ofcutaneous sensation along the inner borders of theforearms, hands and fourth and fifth fingers onboth sides. The lower abdominal reflexes wereabsent. In the lower limbs there was a slightgeneralized weakness, more marked on the left,with considerable spasticity, ankle clonus, ex-aggerated reflexes and bilateral extensor responses.He walked unsteadily on a wide base. Sensation

by copyright. on M

arch 28, 2020 by guest. Protected

http://pmj.bm

j.com/

Postgrad M

ed J: first published as 10.1136/pgmj.26.302.636 on 1 D

ecember 1950. D

ownloaded from

December 1950 LOGUE: Cervical Intervertebral Disc Protrusion 645

*~~ .'.'8.. .. ......l...l....

:... -1 l X - ,......j.^........ . ......T..... ..... ;

FIG. 8.-A diagram illustrating the myelographic appearance of a central disc pro-trusion. The spinal cord is not shown, and the left half of the superior disc andvertebra have been removed. The elevation of the dura for some distance aboveand below the prolapse can be seen producing the elongated filling defect withthe contrast medium (shown in black) passing round the sides.

to light touch, pin-prick and thermal stimuli, andjoint and position sense were normal. There wasa little impairment of vibration sense at the kneesand ankles.

X-ray of the cervical spine showed no ab-normality.On spinal puncture there was no evidence of

block and the protein of the c.s.f. was 50 mgm.per cent.

Myelography performed via the cisternal routeshowed the contrast medium to be held up at theupper border of the fourth cervical vertebra andthen trickle past very slowly on either side. Whenrun up from below there was a partial block at thelower border of the sixth vertebra and again it ranslowly along the sides. The appearances weresuggestive of an intramedullary tumour (Fig. 6).At operation a large central protrusion was

found at the C5-6 disc level and two loose piecesof cartilage were removed.

Post-operatively paraesthesiae in the arms took

three weeks to disappear. The power returned inthe intrinsic muscles of the left hand and thespasticity was less marked in the legs, but now,nearly two years after operation, he has still alittle unsteadiness on walking and turning quickly.

It is an interesting fact that the predominantsymptom in these anterior compressions of thecord by prolapsed discs, both uni- and bilateral, isreferable to the pyramidal tracts and is often muchmore marked than the spino-thalamic tract dis-turbance despite the closer anatomical relationshipof the latter to the protrusion. If the cord werebeing generally ' compressed' by a large lesion,this could perhaps be explained by the greatervulnerability of the large diameter nerve fibres ofwhich the pyramidal tract is mainly composed, butas pointed out earlier, disc lesions do not cause ageneral compression of the cord, but merely anindentation. The probable explanation of thisphenomenon is that given by Kahn:6 As the duralsac is firmly tethered in the spinal canal by the

by copyright. on M

arch 28, 2020 by guest. Protected

http://pmj.bm

j.com/

Postgrad M

ed J: first published as 10.1136/pgmj.26.302.636 on 1 D

ecember 1950. D

ownloaded from

646 POSTGRADUATE MEDICAL JOURNAL December I950

dural sheaths covering the nerve roots, and thespinal cord is fixed within the sac by the ligamentadenticulata, any displacement of the cord back-wards will be resisted by these latter ligaments, andas seen in Fig. 7 this will produce a localized zoneof tension in the area adjacent to their attachment,and as it is in this situation that the pyramidaltracts are lying they will be particularly subject tothis disrupting force. This force will vary withmovements of the neck and will tend to be in-creased by flexion. Owing also to this fixation bythe dural sheaths and ligaments the cord is pre-vented from being displaced backwards againstthe unyielding vertebral laminae so that the fibresin the posterior columns are spared.

InvestigationsSpinal puncture, as already mentioned, usually

shows no evidence of block, at most a partial blockwith a slight rise of protein.

X-rays of the cervical spine may show narrowingof the disc space, but are often normal.

Myelography. This will nearly always showsome obstruction to the flow of contrast, but theappearances may be misleading and resemble thoseof an intramedullary tumour. The reason for thisis that filling defect produced by a median disc isoften several times larger than the actual size of theprolapsed portion of cartilage owing to the factthat as it projects backwards into the spinal canal,it lifts up the dura and separates it in a tent-likefashion from the bodies of the vertebrae for somedistance above and below the disc level. Thiselevation of the dura will be greatest over the top ofthe disc and least at the sides of the spinal canal.As the patient is normally screened in the proneposition with the neck extended, the contrastmaterial flows along the ventral aspect of the duralsac and will be held up by the indentation in thedura some distance away from the actual disc leveland will tend to flow round the sides. Thispicture of an elongated filling defect with a trickleof contrast on either side is usually taken as in-dicative of an intramedullary lesion Fig. 8.

Operative TreatmentThe prolapse should be removed with the least

possible delay after it has been diagnosed, forcontinued pressure will cause irreparable damageto the cord.The operation is best done in the sitting position.

A full laminectomy of at least two and preferablythree vertebrae should be performed as wide accessis needed in order to avoid much manipulation orretraction of the cord. The prolapse is exposed bya transdural approach. On opening the dura thecord will be seen to be kinked backwards by theprolapse and often degenerative changes may beseen in its substance. Three of the dentate liga-ments are divided on each side and the cord isgently rotated to expose the glistening bulge of thedisc, which is not as a rule more than a centimetrein diameter. The anterior layer of the dura andthen the annulus are incised and the loose cartilageremoved. No attempt is made to curette the disc.Extreme gentleness in moving the spinal cord is thedominating feature of the operation, particularly ifthere are any degenerative changes visible in it.In cases xvith severe cord degeneration it isprobably safer not to attempt to remove the discowing to the chance of producing an acute trans-verse lesion (probably from anterior spinal arterythrombosis) and to confine the surgery to divisionof the ligamenta denticulata, so that the cord canmove backwards off the disc. Sometimes theprotrusion consists of a general bulge of the discin the spinal canal, with lipping of the vertebraeabove and below, and without prolapse of thenucleus pulposus. It extends from one side of thespinal canal to the other as a median bar, the cordbeing kinked backwards by it, and the symptomswhich result appear to be caused by repeatedrubbing of the cord across the disc whenever theneck is flexed. Clinically the condition is as-sociated with a long history, is not uncommon inwomen and the symptoms, which usually appear inthe arms as well as the legs, are bilateral from thestart. This type of protrusion is difficult to dealwith as it is impossible to remove the bony hardbulge without danger to the cord and the onlytreatment is division of the dentate ligaments.

REFERENCESi. ELLIOTT, F. A., and KREMER, M. (1945), Lancet, i, 4.2. STOOKEY, B. (1928), Arch. Neurol. and Psych., 20, 275.3. SPURLING, R. G., and SCOVILLE, W. B. (1944), Surgery,

Gvnaecology and Obstetrics, 78, 350.4. YOUNG, J. H. (1948), Med. Journal Australia, 2, 234.5. BUCY, P. C., HEIMBURGER, R. F., and OBERHILL, H. R.

(1948), Journal Neurosurgery, 5, 471.6. KAHN, E. A. (I947), Journal Neurosurgery, 4. xg9.

by copyright. on M

arch 28, 2020 by guest. Protected

http://pmj.bm

j.com/

Postgrad M

ed J: first published as 10.1136/pgmj.26.302.636 on 1 D

ecember 1950. D

ownloaded from