- Email: [email protected]
Protrusion of the Intervertebral Disk
PROTRUSION OF THE INTERVERTEBRAL DISK
HAROLD C. VORIS, M.o.* PROTRUSION or herniation of the intervertebral disk has been known as a pathologic entity for a half century. Although its clinical significance escaped surgeons and neurologists for most of that period, the last ten years have seen an intense interest. in the subject. Operation has been done in a large number of cases (Love and Walsh), and many articles and even monographs have appeared on the subject. It is now apparent that this lesion is much more frequent than was at first suspected; that it can often be recognized by careful clinical history and examination, and that in properly selected cases surgical removal is the treatment of choice. These herniations may occur at any level of the spine but they predominate in the lumbar region and the great majority are from the fourth and fifth lumbar intervertebral disks. Recurrent pain of the so-called root type is the usual complaint; only rarely does the patient present gross neurologic defects. Protrusions from disks above the first lumbar are the most apt to cause such gross neurologic defects by pressure on the spinal cord, simulating cord tumor. Even at these higher levels it has recently been recognized (Semmes and Murphy) that a small, lateral protrusion of the intervertebral disk may cause a syndrome of root pain with minimal objective neurologic findings comparable to the classic syndrome at the lumbar level. Since over 90 per cent of disk protrusions are from the lumbar disks, and most of these from the fourth and fifth lumbar disks, this clinic will be confined to the problems arising in this group. Five cases illustrating certain important points will be presented in some detail with discussion of the individual problems of each case. Then a general discussion of various phases of diagnosis, treatment and results will complete the presentation. CASE I.-M. D. K., a physician, 30 years of age, was referred by his brother, also a physician. Five years before while serving an internship ·he had had an attack of "lumbago" for two weeks. He recovered completely from this for fifteen months and then recurrence took place From Loyola University Medical School and Mercy Hospital-Loyola University Clinics. "Clinical Professor of Surgery (Neurological), Loyola University Medical School; Senior Surgeon (Neurological), Mercy Hospital.
111
112
HAROLD C. VORIS
in the shape of mild "nagging" pain in the lower part of the back. This persisted with remissions and exacerbations. A sacroiliac belt had been of slight help. Treatment with an autogenous vaccine cultured from the nasopharynx had given considerable relief on another occasion. The patient suffered from chronic sinusitis and had noted a definite relationship between "flare-ups" of his sinus trouble and exacerbations of his low back pain. Both he and his brother had consequently considered his low back pain to be the result of absorption of toxins from his chronic sinusitis. One month previously the patient had, for the first time, radiation of pain into the posterior aspect of the right thigh and leg. This pain was worse on coughing, sneezing or straining at stool. No history of definite injury was obtained, but the patient had always been robust and had done considerable heavy work at certain periods of his life. General physical examination was essentially negative. Neurologic examination revealed diminution of the right ankle jerk and hypesthesia to pinprick on the lateral border of the right foot. The circumference of the right calf was 36 cm., the left 37 cm.; the patient was right handed. An air myelogram was performed on March 9, 1940. With the head lowered to an angle of 35 degrees on the tilting table a spinal puncture was performed at the first lumbar interspace and 35 cc. of spinal fluid were removed and air substituted. The total protein content of this fluid was elevated to 78 mg. Lateral and anteroposterior stereoscopic films revealed a defect in the right side of the air column opposite the lumbosacral interspace. Operation on March ] 2, 1940 consisted of a right partial hemilaminectomy of the adjacent portions of the spines and laminae of the fifth lumbar and first sacral vertebrae. This together with resection of the ligamentum flavum exposed an area of dura about 2 by 1.5 cm. Retraction of the right fifth lumbar root exposed a large protrusion of the disk which had not ruptured completely through the posterior longitudinal spinal ligament. A cruciate incision was made in this structure and the fragments of disk material extruded and were readily removed. An unusual amount of fragmented cartilage was removed and a cavity 2 cm. deep in the disk was produced. The dura was not opened and the wound was closed. Convalescence was uneventful and the patient left the hospital on March 29, ] 940. The patient returned to his office three weeks later but was cautioned against lifting or straining for a period of three months. Three months later he considered himself perfectly well. The right ankle jerk was still diminished and straight leg raising on the right still gave slight discomfort. The patient has remained well since, carrying on his practice without interruption. Recently he received a commission in the Medical Corps of the Army of the United States and has been ordered to active duty.
PROTRUSION OF THE INTERVERTEBRAL DISK
113
CO'lmnent.- This case can be considered typical of the syndrome of unilateral protrusion of the fourth or fifth lumbar disk. After a considerable period of recurrent low back pain, unilateral sciatic radiation appeared. The sciatic pain was exacerbated by coughing, sneezing or straining. The ankle jerk was diminished on the affected side and there was definite hypesthesia about the foot on that side. Spinal fluid showed a mild increase in the total protein, and a contrast myelogram showed a definite filling defect of the spinal canal. Operative removal of the protrusion gave an entirely satisfactory res~lt. The exacerbation of the patient's low back pain with recurrence of his chronic sinus infection is of great interest. It shows that the presence of a known focus of infection and even a demonstrable clinical relationship between the focus of infection and the nerve pain in question does not prove the pain to be purely inflammatory or toxic. In this instance the irritated nerve root must have been a locus minoris resistentiae for toxins from the infected sinuses. A considerable numher of patients have low back pain for months or years before the onset of nerve root pain. Roofe has described the innervation of the annulus fibrosus and the· posterior longitudinal ligament. In the early stages of disk protrusion this innervation is responsible for the patient's pain. Only when the protrusion is large enough or far enough laterally to impinge on the nerve root will the patient have radiating pain. Both the nerve root and the protrusion of the disk are slightly affected by postural changes and by muscle spasm. This accounts for the frequent exacerbations, often initiated by muscular strains, and the remissions afforded by bed rest, heat, diathermy and so forth. Many patients who are able and wilIing to limit their physical activity can avoid serious recurrences and live satisfactorily with their disk protrusion. Spinal fluid examination and contrast myelography are not essential in the diagnosis of typical cases and were not here. The total protein content of the spinal fluid is often not elevated, and this finding while of great help when positive has no negative value. Contrast myelograms were thought at one time to be necessary in all cases. In fact it is doubtful if the interverbral disk syndrome would have become well recognized without the aid of contrast myelography. Air and oxygen are the least desirable of the mediums in general use from a roentgenographic standpoint, but both have the advantage of rapid and complete absorption, leaving no trace of their presence and both produce little or no irritation. Lipiodol is far superior from a roentgenographic standpoint but is difficult to remove except at operation. In the writer's experience no irritative effects from lipiodol are noted
114
HAROLD
c.
voiuS
A B Fig. 29 (Case l).-A, Preoperative roentgenogram, anteroposterior view. B, Postoperative roentgenogram, anteroposterior view. Note small amount of bone removal.
A B Fig. 30 (Case I).-A, Preoperative roentgenogram, lateral view. B, Postoperative (six months) roentgenogram, lateral view. There is no change in the lumbosacral disk space which was narrowed before operation.
PROTRUSION OF THE INTli:RVERTEBRAL DISK
115
clinically as a rule; rarely such effects are definitely produced. The new substance, pantopaque, is comparable to lipiodol from a roentgenographic standpoint and has the advantage of being readily removable by aspiration through a spinal needle. It is now becoming generally available. This patient has had a good operative result over a four year period. The operative procedure consisted of simple removal of th(pprotruded and fragmented portion of the disk through a limited but adequate operative exposure. As Fig. 29 shows, bone removal was minimal. Although a large cavity was produced in the fifth lumbar disk, a lateral roentgenogram six months later compared with a preoperative roentgenogram (Fig. 30) showed no decrease in the intervertebral space. Spinal fusion was not done in this case although one of the so-called indications was present: that of low back pain for several years before the onset of sciatic pain. CASE H.-M. c., a punch press operator, 45 years of age, had suffered from recurrent low back pain for the past twelve years. He had been treated more or less continuously as a case of spinal arthritis. Two weeks before admission he had begun to have pain radiating into the left lower extremity but was able to continue work until five days later when on arising in the morning he was paralyzed from the knees down. Since that time urinary retention and fecal incontinence had been present and the patient had been bedridden. Neurologi~al examination revealed weakness of the thigh muscles with paralysis of the calf and peroneal muscles. The right knee jerk was active, the left absent and both ankle jerks absent. Cutaneous sensation was lost over the posterior aspects of the buttocks and thighs (third to fifth sacral dermatomes) and impaired on the posterior aspects of the legs, over the feet and the anterior aspect of the lower third of both legs (fourth lumbar to second sacral dermatomes). There was an area of hyperesthesia to pinprick on the dorsum of each foot. Vibration sense was moderately impaired at the left ankle and slightly at the right. Position sense was impaired in the left toes. A neurological consultant had performed a spinal puncture and injected lipiodol. He had not obtained fluid at the third or fourth lumbar interspaces but had obtained xanthochromic fluid that coagulated on standing at the fifth lumbar interspace. No rise in spinal manometric pressl!re had been noted on bilateral jugular compression. X-rays taken after his injection of lipiodol at that level showed all of the lipiodol below the lower part of the body of the fourth lumbar vertebra. The preoperative diagnosis was tumor of the cauda equina opposite the third and fourth lumbar vertebrae. Operation was performed March 26, 1940 and consisted of laminectomy of the spines and laminae of the third, fourth and fifth lumbar vertebrae. When the lamina
116
HAROLD C. VORIS
of the fourth lumbar vertebra was removed on the left side, a tightly rolled extradural mass extruded itself and spontaneously unrolled. It proved to be a ragged piece of fibrocartilage 4 by 2.5 by 0.7 cm. (Fig. 31). Its inferior and anterior corner was still attached to the intervertebral disk between the fourth and fifth lumbar vertebra. It was readily removed. The ragged cavity in the intervertebral disk proved to contain no loose or fragmented cartilage. The dura was opened and the previously in,jected lipiodol was removed. The. nerve roots were swollen and markedly injected. Convalescence was uneventful. At the patient's dismissal from the hospital three weeks later bladder function had satisfactorily returned but the neurologic status was otherwise unchanged. Nine months later he was walking well with only moderately diminished strength and
Fig 31 (Case 11) .-Photograph of extruded portion of disk removed at operation.
tone in the calf muscles. The left patellar reflex was diminished. Both ankle jerks were present but diminished. Sensation was still impaired in the third to fifth sacral dermatomes bilaterally. The patient claimed no difficulty with bladder function but admitted some difficulty in controlling the rectal sphincter. Four years later he reported good control of bladder and bowels, residual atrophy of the calf muscles, and complained only of easy fatigue in his lower extremities. He estimated his percentage of recovery at 90 per cent.
Comment.-This was an extraordinary case. After years of low back pain, sudden and complete loss of neurologic function below the fourth lumbar roots developed, preceded by root pain of only a few days' duration. In the absence of a definite injury or strain it is diffi-
PROTRUSION OF THE INTERVERTEBRAL DISK
117
. cult to explain the massive extrusion of the ruptured cartilage. Since then I have had a simila,r case. A 45 year old priest had had low back pain for ten years with recurrent sciatic radiation for a year. While in the hospital receiving conservative treatment he coughed at stool one morning and was seized with excruciating low bacl~ and bilateral loss of function below the third lumbar segment. A preoperative diagnosis of massive extrusion of intervertebral disk cartilage was made and verified at operation. The operative findings were similar to those of' Case 11 except that the extrusion was one segment higher. A similar case was reported by Middleton and Teacher in 1911, and two others by Dandy in 1929. Recently French and Payne have reported eight cases of compression of the cauda equina due to disk protrusions. Such cases as this are rare but should be thought of in the event of sudden paraplegia, especially if the onset is associated with muscular strain or wrenching. If the extrusion is below the first lumbar disk the prognosis for recovery is good, especially with early operation. Such an accident above the first lumbar disk will usually result in permanent damage to the spinal cord. Localization is obvious from the neurologic findings; spinal puncture confirms the presence of a subarachnoid block; contrast myelography should not be necessary. CASE III.-M. N., a 40 year old mason, had injured himself in a fall twenty years before when he landed on his buttocks. Recurrent, low back pain had plagued him since and for the past four years there had been recurrent left sciatic radiation of the pain. This was exacerbated by coughing or sneezing and when sitting for any length of time numbness and tingling of the left lower extremity was noted. About a month l;>efore, right sciatic pain had appeared but was not as severe as on the left nor were there any paresthesias on the right side. Examination revealed a markedly positive Lasegue (straight leg raising) sign on the left and a mildly positive one on the right. There was tenderness to palpation at· the lumbosacral junction. Both ankle jerks were absent and there was hypesthesia to pinprick on the border of both feet. An air myelogram was carried out, 20 cc. of spinal fluid being removed and air substituted. The total protein content of the fluid was 58 mg. The myelograms were not satisfactory. No air was seen below the fourth lumbar interspace. Op~ration on September 22, 1942 consisted of partial laminectomy of the spines and laminae of the fourth and fifth lumbar and the first sacral vertebrae. The ligamentum flavum was resected at both the fourth and fifth lumbar interspaces. Part of the lamina of the fifth lumbar vertebra, a ridge of bone 15 mm. wide, was preserved. The fifth lumbar and first sacral roots were markedly swollen but no evidence of disk protrusion at the lumbosacral level was found. At the
118
HAROLD C. VORIS
level of the fourth interspace there was a small protrusion on the left side near the midline. There was no rupture. of the posterior longitudinal ligament. When the protrusion was incised, very little fragmented disk material escaped or could be removed. However, there waS an extensive degeneration of the intervertebral disk as there was a cavity about 2 cm. deep in the disk into which· the aspirator tip or curet could be readily introduced. The dura was not opened and the wound was closed. The immediate convalescence was· uneventful a~d the patient was dismissed from the hospital on October 8, 1942 .. He was next seen on October 22, 1942 complaining of "a catch in his back" and bilateral radiation of pain into both thighs anteriorly. There was a marked list of the lumbar spine to the right and straight leg raising was painful, especially on the left. He was readmitted to the hospital and improved rapidly with inductotherm treatments, being dismissed again four days later. However, he continued to complain of low back pain and has not been.able to work steadily. Spinal fusion has been advised but the patient has refused further surgery.
Comment.-This case is an example of an unsatisfactory result. Spinal fusion was certainly indicated in this case and should have been done at the operation for removal of the disk protrusion. The evidence at operation of extensive disk degeneration without any marked protrusion suggests that the protrusion was of relatively little importance and the pathologic change within the disk of chief importance. This patient's attitude and personality made him a poor choice for surgical treatment. He was pessimistic before operation about the likelihood of relief and he had a low· pain threshold with a tendency to exaggerate his complaints. For many years he had complained of a "weak stomach" with frequent gastric upsets, although repeated examinations by capable gastroenterologists had never revealed any organic cause for these disturbances. We would have done well not to have advised operation on this patient; if operated on he should have had a spinal fusion combined with removal of the disk protrusion. CASE IV.-J. N., a 35 year old grain broker, had had recurrent, low back pain for eight years, usually brought on by exercise and more frequent in the winter months. Extensive and prolonged orthopedic treatment had failed to give relief. For a week the pain had radiated down the posterior aspect of the right lower extremity and had been exacerbated by coughing or sneezing. The patient had been an active athlete in high school and college and had done heavy work during school vacations. He could not, however, give a history of a specific back strain or injury.
PROTRUSION OF THE INTERVERTEBRAL DISK
119
Examination revealed a moderately positive right Lasegue sign and definite lumbosacral tenderness. The right ankle jerk was diminished; there were no sensory changes. An air myelogram was carried out, 30 cc. of spinal fluid being removed and air substituted. The total protein content of the spinal fluid was 67 mg. The myelograms showed 11 defect in the air column on the right at the fourth lumbar interspace. Because of the minimal objective neurologic findings and the long history of low back pain, and with the case of M. N. in mind, further orthopedic consultation was advised. Dr. Perry Rogers saw the patient, concurred in the diagnosis of protrusion of an intervertebral disk and advised the combination of spinal fusion with removal of the
A
B
Fig. 32 (Case IV) .-A, Postoperative roentgenogram, anteroposterior view, six weeks after combined operation. B, Lateral view.
disk protrusion. The preoperative diagnosis was protrusion of the fourth intervertebral disk on the right. Operation on February 2, 1943 consisted of exposure .of the spines and laminae from the fourth lumbar to the second sacral vertebrae. The ligamentum flavUlP was widely resected at the fourth and fifth lumbar interspaces and a small portion of the adjacent laminae nibbled away. There was no evidence of disk protrusion at the fourth lumbar interspace. On the right, near the midline at the lumbosacral interspace, there was ·a large protrusion. The posterior longitudinal ligament was not ruptured but was so thin over the protrusion that it ruptured on gentle probing. A large amount of fragmented disk material was removed. The cavity in the disk after removal of the
120
HAROLD C. VORIS
fragmented material was 3 cm. deep. Dr. Rogers then performed a Hibbs' type spinal fusion, using plaques of bone from the outer table of the right ilium, in addition to slabs of bone from the spinous processes, the laminae, and the posterior aspect of the sacrum. Convalescence was uneventful. The patient was ambulatory in a body cast at the time of his dismissal on February 24, 1943. The cast was removed six weeks after operation. Figure 32 shows roentgenograms taken at that time. During the summer of 1943 he played tennis without ill effects. When last seen in May of 1944 he was perfectly well and was enjoying golf, badminton and tennis. CO'fJlment.- The result in this case is in marked contrast to that obtained in Case III with a comparable history. However, it would not be accurate to carry the comparison further. This patient was a much more stable individual-a very intelligent and highly successful business man who cooperated fully in his treatment. Moreover, he had a large protrusion of the disk which adequately accounted for his root pain. However, the very satisfactory result speaks well for the combined operation. It should be noted that the air myelogram not only failed to localize the lesion but was actually misleading, indicating a nonexistent protrusion at the fourth lumbar disk. Even at best air myelography is far inferior fr0111 a roentgenographic standpoint to lipiodol or pantopaque.
CASE V.-D. M., a 27 year old housewife, had strained her back nine months before while carrying her baby upstairs in its carriage. Low back pain followed and within a few days became severe, and right sciatic radiation was noted with numbness of the right buttock and posterior aspe.ct of the right thigh. The numbness had gradually improved but still persisted in considerable degree. She had been delivered of another child six months later but did not feel that her labor pains had been different from former labors or that labor had affected her low back or sciatic pain. The pain had been recurrent with every effort to resume normal activity. Examination revealed a moderately positively Lascgue sign on the right and absence of the right ankle jerk. There was marked hypesthesia to pinprick in the right side of the perineum and the posterior aspect of the right thigh (third to fifth sacral dermatomes). An air myelogram was done; 40 cc. of fluid were removed and air substituted. The total protein content of the spinal fluid was 50 mg. per 100 cc. The myelograms showed a shift of the air column to the left opposite the fifth lumbar interspace. A diagnosis was made of a large disk protrusion on the right at the lumbosacral level. Neoplasm was considered a possibility because of the involvement of sacral dermatomes.
PROTRUSION OF TB E INTERVERTEBRAL DISK
121
Operation on January 8, 1944 was a right hemilaminectomy of the fifth lumbar vertebra. Initially the ligamentum flavum was resected on the right at the fourth and fifth lumbar interspaces and the resultant opening then enlarged by nibbling away the adiacent laminae slightly with rongeurs. With this exposure no disk protrusion could be seen, hut after complete removal of the right si~ of the lamina of the fifth lumbar vertebra a protrusion of the lumbosacral disk could be visualized near the midline projecting upward so that it could not be seen through the interlaminar space. The posterior longitudinal ligament was not ruptured; after its incision a considerable amount of fragmented cartilage and nucleus pulposus was removed. Extradural bleeding was trouhlesome and finally required several muscle pledgets to control. Convalescence was uneventful and the patient left the hospital on January 24, 1944. The sensation in the right perineum, buttock and posterior thigh had improved, especially over the perineum and buttock. A month later no objective sensory disturbance could be found although subjective numbness of the posterior aspect of the right thigh was still present. The patient has not been seen since but reports by letter that she is entirely well.
Comment.-This patient's sciatic radiation began within a few days of her low back pain. The onset was related to a definite back strain. Unusual features were the early paresthesias in the sacral dermatomes and the objective sensory disturbances in these dermatomes on examination. This protrusion near the midline was apparently large from the onset so that sciatic radiation of pain and sensory di~turbances appeared very early. Some improvement had followed conservative treatment but she had been practically incapacitated from the time of her injury. She 'was six months' pregnant at the time of the onset but what role that played in the severity and persistence of her symptoms is difficult to assess. She noted no improvement after delivery. At operation this patient's disk protrusion could not be visualized through the usual interlaminar approach and complete hemilaminectomy of the fifth lumbar vertebra was necessary. Neurologic surgeons know that laminectomy, even if extensive, is not disabling nor does it weaken the spine if the articular facets are preserved. Other things being equal it is of course desirable to remove as little tissue and destroy normal relatio~ships as little as possible in the removal of a disk protrusion. This desire should not lead to the failure to visualize the protrusions or adequately remove them through lack of exposure. The surgeon should not operate unless he is convinced that a disk protrusion is present; if he does operate, while his initial exposure may be limited,
122
HAROLD C. VORIS
he should never fail to make an exposure adequate remove the obstruction.
tD
visualize and
GENERAL COMMENT
The History.-The importance of a good history cannot be over-
estimated. Root pain, whether in the sciatic radiation or elsewhere, has certain rather constant characteristics. When present its location is constant, it is often worse at night, and it is usually exacerbated by coughing, sneezing or muscular straining. The past history must be carefully inquired into for attacks of back pain or sciatica in the past and for back injury or strain. Examinaton.-On examination the patient may limp on the affected side if the pain is severe. Often the lumbar spine lists away from the affected side, occasionally to that side. Localized tenderness at the affected interspace is a frequent finding. Straight leg raising is almost always painful, sometimes extremely so. The absence or impairment of the ankle jerk on the affected side or some degree of sensory disturbance in the affected dermatome or dermatomes is exceedingly important. In my own experience such obj ective neurologic findings were absent in only 15 per cent of the cases in which a disk protrusion was found at operation. On the other hand, in the cases in which I failed to find a disk protrusion, such objective neurologic findings were never present. It is obvious from this that, in the absence of objective neurologic findings, great care should be exercised in making a diagnosis of protruded disk. Probably contrast myelography should be used in all of these cases. It must be emphasized that the objective neurologic findings referred to are minimal and must be sought for carefully and skillfully. Bradford and Spurling, and Semmes have well emphasized the importance of careful neurologic examination. . Selection of Patients for Operation.-The selection of patients for operation is very important. As has already been stated, many patients with mild symptoms can live fairly comfortably with their disk protrusion if they are brought through an occasional exacerbation of their symptoms by conservative treatment. This is particularly true of those individuals who are fortunate enough to be able and willing to avoid hard physical labor or strenuous exercise. Many patients with acute back strain have injury to the intervertebral disk and the annulus fibrosus or posterior longitudinal spinal ligament. However, with rest and perhaps temporary immobilization healing takes place and there is no recurrence of symptoms. Perhaps an improvement in the early management of low back injuries might lessen the incidence of later disk protrusions. In addition to those patients whose symptoms are not sufficiently marked to warrant surgical intervention, there is a group
PROTRUSIO~ OF THE INTERVERTEBRAL DISK
123
of patients who do have severe and disabling complaints. However, these individuals, because of their personality and attitude (Case Ill) are likely to continue to complain after an apparently successful operative procedure or they may develop a new set of complaints after operation. All surgeons know this type of patient and learn to avoid elective operative procedures on him whenever possible. Another group of patients with disk protrusions that is notoriously apt to obtain poor results from surgery consists of the compensatjon cases. Where it is feasible, the patient with a compensation problem should be encouraged to obtain a final settlement of his case and then seek relief from surgery. Such settlement should of course take into account his prospective medical and hospital expense. When surgery is carried out while the patient is still receiving compensation, the patient should be told frankly that after operation he will be expected gradually to resume full activity and finally return to work even at the expense of minor discomfort. Patients in this group with low pain thresholds, inadequate personalities, or who indicate resentment against their employer or the insurance carrier will seldom obtain a good result, at least during the period of compensation. The patient who has legal proceedings pending, either in court or before the Industrial Board, will seldom cease to complain until after these proceedings have been settled. Patients who do require operation fall into three main groups. Those in the first group have relatively mild symptoms but circumstances or the patient's own desires (Case IV) demand considerable physical activity and the persistent recurrence of symptoms finally brings them to operation. If they can change their occupation or if they will give up strenuous exercise, an operation may be avoided. Many cannot do the former; some refuse the latter alternative. Selection of cases must be carried out carefully in this group. A second group in spite of conservative treatment and limitation of activity continues to have recurrence of pain and also finally comes to operation (Case I). Patients in this group present fewer problems than the first group. Trial of conservative treatment has been adequate and the patient has been cooperative. The persistence of recurrences under such conditions warrants surgical intervention. Finally there is a group of patients whose pain is constant and severe with any activity (Case V) or who develop marked objective neurologic disability (Case Il). These patients present an absolute indication for operation because of their disability and suffering. Once the diagnosis is established, and in this group that is usually not difficult, surgery is indicated.
124
HAROLD C. VORIS
•
Surgical Management.-The surgical removal of a disk protrusion, especially through a limited exposure, requires an accurate anatomical knowledge of the region involved plus certain special instruments and technic. The management of epidural bleeding is often troublesome, interfering with the exposure and removal of the lesion. If it is not controlled before the closure of the wound, postoperative hematoma with serious neurologic sequelae may occur. The use of suction and electrocoagulation is of great help. Small implants of muscle or, as recently suggested by Ingraham, Bailey and Nulsen, of pieces of fibrin foam soaked in thrombin may Le necessary. Small cottonoid strips, cotton pledgets, special nerve root retractors, special rongeurs and hiopsy punches are all of great assistance and represent part of the regular armamentarium of the neurologic surgeon. The most debated question in the surgical management of these cases is that of whether spir/al fusioll should be combined with removal of the disk protrusion-the so-called "combined operation." Opinions vary from the extreme that it should be done in every case of disk protrusion, to the other extreme, that it is seldom if ever necessary. Only time and further observation of the results in large numbers of cases can give the answer. For the present it is my opinion that the combined operation should be considered (1) in cases of multiple or recurrent disk protrusions, (2) where there is roentgenographic, clinical or surgical evidence of inherent instability of the lumbosacral spine, (3) where low back pain is severe and disabling for a long period before the onset of sciatic radiation, and (4) where the patient's occupation is one of heavy labor or demands a great deal of lifting. Obviously the best interests of the patient are served by the full cooperation of neurologic and orthopedic surgeons, and it is no accident that the most advances and the best results in the management of these cases have come from those clinics and institutions where such cooperation is routine and where both the neurologic and orthopedic surgeons have contributed their share to the problem. Postoperative Management.-The length of time that a patient should spend in bed after the operation and the period of convalescence before returning to full activity are in my opinion very important points. Since any operative repair of the rupture of the posterior longitudinal spinal ligament or annulus fibrosus is not technically feasible, we are forced to depend on natural means-the proliferation of fibrous connective (scar) tissue-for the repair of these structures and the cavity in the disk left by the removal of fragmented nucleus pulposus and fibrocartilage. It is our practice to keep the patient in bed for two
PROTRUSION OF THE INTERVERTEBRAL DISK
125
weeks after the removal of a disk protrusion and then allow gradual resumption of activity. Light work may be resumed in six weeks; full physical activity, especially heavy lifting or strenuous work, should be postponed for three months. Some will object to this, claiming that such long periods of inactivity tend to destroy the patient's confidence in the result and to increase the number of patients with poor results. It is true, especially in compensation cases, that every effort should be made to discourage the development of an attitude of chronic invalidism. However, if an adequate explanation is given the patient for the prolonged convalescence and if, after the prescribed period has passed, firm insistence is made on resumption of activity, no serious difficulty should be encountered. Too often a surgeon fails to exercise adequate observation Of control of the patient's activity during convalescence and is then disappointed at the patient's refusal to undertake immediate full activity. BIBLIOGRAPHY
J. S.: Sciatica Caused by Intervertebral Disks. J. Bone & Joint Surg., 19:323-342, 1937. 2. Bradford, F. K. and Spurling, R. G.: The Intervertebral Disk. Springfield, Ill., Charles C Thomas, 158 pp., 1941. 3. Dandy, W. E.: Loose Cartilage from Intervertebral Disk Simulating Tumor of Spinal Cord. Arch. Surg., 19:660-672, 1929. 4. French, S. D. and Payne, J. T.: Cauda Equina Compression Syndrome with Herniated Nucleus Pulposus. Ann. Surg., 120:73-87, 1944. 5. Ingraham, F. D., Bailey, O. T. and Nulsen, F. E.: Studies on Fibrin Foam as a Hemostatic Agent in Neurosurgery, with Special Reference to Its Comparison with Muscle. J. Neurosurg., 1:171-182, 1944. 6. Love, J. G. and Walsh, M. N.: Protruded Intervertebral Disks. Surg., Gynec. & Obst., 77:497-509, 1943. 7. Roofe, P. G.: Innervation of Annulus Fibrosus and Posterior Longitudinal Ligament: Fourth and Fifth Lumbar Level. Arch Neuro!. & Psychiat., 44:100-103, 1940. H. Semmes, R. E., Diagnosis of Ruptured Intervertebral Disk without Contrast Myelography, and Comment upon Recent Experience with Modified Hemilaminectomy for Their Removal. Yale J. Bio!. & Med., 11:433-437, 1939. 9. Semmes, R. E. and lHurphy, F.: The Syndrome of Unilateral Rupture of the Sixth Cervical Intervertebral Disk with Compression of the Seventh Cervical Nerve Roots. J.A.M.A., 121:1209-1215, 1943. 10. Spurling, R. G. and Grantham, E. G.: Neurologic Picture of Herniations of the Nucleus Pulposus in the Lower Part of the Lumbar Region. Arch. Surg., 40:375-388, 1940. 1. Barr,
HAROLD C. VORIS, M.o.* PROTRUSION or herniation of the intervertebral disk has been known as a pathologic entity for a half century. Although its clinical significance escaped surgeons and neurologists for most of that period, the last ten years have seen an intense interest. in the subject. Operation has been done in a large number of cases (Love and Walsh), and many articles and even monographs have appeared on the subject. It is now apparent that this lesion is much more frequent than was at first suspected; that it can often be recognized by careful clinical history and examination, and that in properly selected cases surgical removal is the treatment of choice. These herniations may occur at any level of the spine but they predominate in the lumbar region and the great majority are from the fourth and fifth lumbar intervertebral disks. Recurrent pain of the so-called root type is the usual complaint; only rarely does the patient present gross neurologic defects. Protrusions from disks above the first lumbar are the most apt to cause such gross neurologic defects by pressure on the spinal cord, simulating cord tumor. Even at these higher levels it has recently been recognized (Semmes and Murphy) that a small, lateral protrusion of the intervertebral disk may cause a syndrome of root pain with minimal objective neurologic findings comparable to the classic syndrome at the lumbar level. Since over 90 per cent of disk protrusions are from the lumbar disks, and most of these from the fourth and fifth lumbar disks, this clinic will be confined to the problems arising in this group. Five cases illustrating certain important points will be presented in some detail with discussion of the individual problems of each case. Then a general discussion of various phases of diagnosis, treatment and results will complete the presentation. CASE I.-M. D. K., a physician, 30 years of age, was referred by his brother, also a physician. Five years before while serving an internship ·he had had an attack of "lumbago" for two weeks. He recovered completely from this for fifteen months and then recurrence took place From Loyola University Medical School and Mercy Hospital-Loyola University Clinics. "Clinical Professor of Surgery (Neurological), Loyola University Medical School; Senior Surgeon (Neurological), Mercy Hospital.
111
112
HAROLD C. VORIS
in the shape of mild "nagging" pain in the lower part of the back. This persisted with remissions and exacerbations. A sacroiliac belt had been of slight help. Treatment with an autogenous vaccine cultured from the nasopharynx had given considerable relief on another occasion. The patient suffered from chronic sinusitis and had noted a definite relationship between "flare-ups" of his sinus trouble and exacerbations of his low back pain. Both he and his brother had consequently considered his low back pain to be the result of absorption of toxins from his chronic sinusitis. One month previously the patient had, for the first time, radiation of pain into the posterior aspect of the right thigh and leg. This pain was worse on coughing, sneezing or straining at stool. No history of definite injury was obtained, but the patient had always been robust and had done considerable heavy work at certain periods of his life. General physical examination was essentially negative. Neurologic examination revealed diminution of the right ankle jerk and hypesthesia to pinprick on the lateral border of the right foot. The circumference of the right calf was 36 cm., the left 37 cm.; the patient was right handed. An air myelogram was performed on March 9, 1940. With the head lowered to an angle of 35 degrees on the tilting table a spinal puncture was performed at the first lumbar interspace and 35 cc. of spinal fluid were removed and air substituted. The total protein content of this fluid was elevated to 78 mg. Lateral and anteroposterior stereoscopic films revealed a defect in the right side of the air column opposite the lumbosacral interspace. Operation on March ] 2, 1940 consisted of a right partial hemilaminectomy of the adjacent portions of the spines and laminae of the fifth lumbar and first sacral vertebrae. This together with resection of the ligamentum flavum exposed an area of dura about 2 by 1.5 cm. Retraction of the right fifth lumbar root exposed a large protrusion of the disk which had not ruptured completely through the posterior longitudinal spinal ligament. A cruciate incision was made in this structure and the fragments of disk material extruded and were readily removed. An unusual amount of fragmented cartilage was removed and a cavity 2 cm. deep in the disk was produced. The dura was not opened and the wound was closed. Convalescence was uneventful and the patient left the hospital on March 29, ] 940. The patient returned to his office three weeks later but was cautioned against lifting or straining for a period of three months. Three months later he considered himself perfectly well. The right ankle jerk was still diminished and straight leg raising on the right still gave slight discomfort. The patient has remained well since, carrying on his practice without interruption. Recently he received a commission in the Medical Corps of the Army of the United States and has been ordered to active duty.
PROTRUSION OF THE INTERVERTEBRAL DISK
113
CO'lmnent.- This case can be considered typical of the syndrome of unilateral protrusion of the fourth or fifth lumbar disk. After a considerable period of recurrent low back pain, unilateral sciatic radiation appeared. The sciatic pain was exacerbated by coughing, sneezing or straining. The ankle jerk was diminished on the affected side and there was definite hypesthesia about the foot on that side. Spinal fluid showed a mild increase in the total protein, and a contrast myelogram showed a definite filling defect of the spinal canal. Operative removal of the protrusion gave an entirely satisfactory res~lt. The exacerbation of the patient's low back pain with recurrence of his chronic sinus infection is of great interest. It shows that the presence of a known focus of infection and even a demonstrable clinical relationship between the focus of infection and the nerve pain in question does not prove the pain to be purely inflammatory or toxic. In this instance the irritated nerve root must have been a locus minoris resistentiae for toxins from the infected sinuses. A considerable numher of patients have low back pain for months or years before the onset of nerve root pain. Roofe has described the innervation of the annulus fibrosus and the· posterior longitudinal ligament. In the early stages of disk protrusion this innervation is responsible for the patient's pain. Only when the protrusion is large enough or far enough laterally to impinge on the nerve root will the patient have radiating pain. Both the nerve root and the protrusion of the disk are slightly affected by postural changes and by muscle spasm. This accounts for the frequent exacerbations, often initiated by muscular strains, and the remissions afforded by bed rest, heat, diathermy and so forth. Many patients who are able and wilIing to limit their physical activity can avoid serious recurrences and live satisfactorily with their disk protrusion. Spinal fluid examination and contrast myelography are not essential in the diagnosis of typical cases and were not here. The total protein content of the spinal fluid is often not elevated, and this finding while of great help when positive has no negative value. Contrast myelograms were thought at one time to be necessary in all cases. In fact it is doubtful if the interverbral disk syndrome would have become well recognized without the aid of contrast myelography. Air and oxygen are the least desirable of the mediums in general use from a roentgenographic standpoint, but both have the advantage of rapid and complete absorption, leaving no trace of their presence and both produce little or no irritation. Lipiodol is far superior from a roentgenographic standpoint but is difficult to remove except at operation. In the writer's experience no irritative effects from lipiodol are noted
114
HAROLD
c.
voiuS
A B Fig. 29 (Case l).-A, Preoperative roentgenogram, anteroposterior view. B, Postoperative roentgenogram, anteroposterior view. Note small amount of bone removal.
A B Fig. 30 (Case I).-A, Preoperative roentgenogram, lateral view. B, Postoperative (six months) roentgenogram, lateral view. There is no change in the lumbosacral disk space which was narrowed before operation.
PROTRUSION OF THE INTli:RVERTEBRAL DISK
115
clinically as a rule; rarely such effects are definitely produced. The new substance, pantopaque, is comparable to lipiodol from a roentgenographic standpoint and has the advantage of being readily removable by aspiration through a spinal needle. It is now becoming generally available. This patient has had a good operative result over a four year period. The operative procedure consisted of simple removal of th(pprotruded and fragmented portion of the disk through a limited but adequate operative exposure. As Fig. 29 shows, bone removal was minimal. Although a large cavity was produced in the fifth lumbar disk, a lateral roentgenogram six months later compared with a preoperative roentgenogram (Fig. 30) showed no decrease in the intervertebral space. Spinal fusion was not done in this case although one of the so-called indications was present: that of low back pain for several years before the onset of sciatic pain. CASE H.-M. c., a punch press operator, 45 years of age, had suffered from recurrent low back pain for the past twelve years. He had been treated more or less continuously as a case of spinal arthritis. Two weeks before admission he had begun to have pain radiating into the left lower extremity but was able to continue work until five days later when on arising in the morning he was paralyzed from the knees down. Since that time urinary retention and fecal incontinence had been present and the patient had been bedridden. Neurologi~al examination revealed weakness of the thigh muscles with paralysis of the calf and peroneal muscles. The right knee jerk was active, the left absent and both ankle jerks absent. Cutaneous sensation was lost over the posterior aspects of the buttocks and thighs (third to fifth sacral dermatomes) and impaired on the posterior aspects of the legs, over the feet and the anterior aspect of the lower third of both legs (fourth lumbar to second sacral dermatomes). There was an area of hyperesthesia to pinprick on the dorsum of each foot. Vibration sense was moderately impaired at the left ankle and slightly at the right. Position sense was impaired in the left toes. A neurological consultant had performed a spinal puncture and injected lipiodol. He had not obtained fluid at the third or fourth lumbar interspaces but had obtained xanthochromic fluid that coagulated on standing at the fifth lumbar interspace. No rise in spinal manometric pressl!re had been noted on bilateral jugular compression. X-rays taken after his injection of lipiodol at that level showed all of the lipiodol below the lower part of the body of the fourth lumbar vertebra. The preoperative diagnosis was tumor of the cauda equina opposite the third and fourth lumbar vertebrae. Operation was performed March 26, 1940 and consisted of laminectomy of the spines and laminae of the third, fourth and fifth lumbar vertebrae. When the lamina
116
HAROLD C. VORIS
of the fourth lumbar vertebra was removed on the left side, a tightly rolled extradural mass extruded itself and spontaneously unrolled. It proved to be a ragged piece of fibrocartilage 4 by 2.5 by 0.7 cm. (Fig. 31). Its inferior and anterior corner was still attached to the intervertebral disk between the fourth and fifth lumbar vertebra. It was readily removed. The ragged cavity in the intervertebral disk proved to contain no loose or fragmented cartilage. The dura was opened and the previously in,jected lipiodol was removed. The. nerve roots were swollen and markedly injected. Convalescence was uneventful. At the patient's dismissal from the hospital three weeks later bladder function had satisfactorily returned but the neurologic status was otherwise unchanged. Nine months later he was walking well with only moderately diminished strength and
Fig 31 (Case 11) .-Photograph of extruded portion of disk removed at operation.
tone in the calf muscles. The left patellar reflex was diminished. Both ankle jerks were present but diminished. Sensation was still impaired in the third to fifth sacral dermatomes bilaterally. The patient claimed no difficulty with bladder function but admitted some difficulty in controlling the rectal sphincter. Four years later he reported good control of bladder and bowels, residual atrophy of the calf muscles, and complained only of easy fatigue in his lower extremities. He estimated his percentage of recovery at 90 per cent.
Comment.-This was an extraordinary case. After years of low back pain, sudden and complete loss of neurologic function below the fourth lumbar roots developed, preceded by root pain of only a few days' duration. In the absence of a definite injury or strain it is diffi-
PROTRUSION OF THE INTERVERTEBRAL DISK
117
. cult to explain the massive extrusion of the ruptured cartilage. Since then I have had a simila,r case. A 45 year old priest had had low back pain for ten years with recurrent sciatic radiation for a year. While in the hospital receiving conservative treatment he coughed at stool one morning and was seized with excruciating low bacl~ and bilateral loss of function below the third lumbar segment. A preoperative diagnosis of massive extrusion of intervertebral disk cartilage was made and verified at operation. The operative findings were similar to those of' Case 11 except that the extrusion was one segment higher. A similar case was reported by Middleton and Teacher in 1911, and two others by Dandy in 1929. Recently French and Payne have reported eight cases of compression of the cauda equina due to disk protrusions. Such cases as this are rare but should be thought of in the event of sudden paraplegia, especially if the onset is associated with muscular strain or wrenching. If the extrusion is below the first lumbar disk the prognosis for recovery is good, especially with early operation. Such an accident above the first lumbar disk will usually result in permanent damage to the spinal cord. Localization is obvious from the neurologic findings; spinal puncture confirms the presence of a subarachnoid block; contrast myelography should not be necessary. CASE III.-M. N., a 40 year old mason, had injured himself in a fall twenty years before when he landed on his buttocks. Recurrent, low back pain had plagued him since and for the past four years there had been recurrent left sciatic radiation of the pain. This was exacerbated by coughing or sneezing and when sitting for any length of time numbness and tingling of the left lower extremity was noted. About a month l;>efore, right sciatic pain had appeared but was not as severe as on the left nor were there any paresthesias on the right side. Examination revealed a markedly positive Lasegue (straight leg raising) sign on the left and a mildly positive one on the right. There was tenderness to palpation at· the lumbosacral junction. Both ankle jerks were absent and there was hypesthesia to pinprick on the border of both feet. An air myelogram was carried out, 20 cc. of spinal fluid being removed and air substituted. The total protein content of the fluid was 58 mg. The myelograms were not satisfactory. No air was seen below the fourth lumbar interspace. Op~ration on September 22, 1942 consisted of partial laminectomy of the spines and laminae of the fourth and fifth lumbar and the first sacral vertebrae. The ligamentum flavum was resected at both the fourth and fifth lumbar interspaces. Part of the lamina of the fifth lumbar vertebra, a ridge of bone 15 mm. wide, was preserved. The fifth lumbar and first sacral roots were markedly swollen but no evidence of disk protrusion at the lumbosacral level was found. At the
118
HAROLD C. VORIS
level of the fourth interspace there was a small protrusion on the left side near the midline. There was no rupture. of the posterior longitudinal ligament. When the protrusion was incised, very little fragmented disk material escaped or could be removed. However, there waS an extensive degeneration of the intervertebral disk as there was a cavity about 2 cm. deep in the disk into which· the aspirator tip or curet could be readily introduced. The dura was not opened and the wound was closed. The immediate convalescence was· uneventful a~d the patient was dismissed from the hospital on October 8, 1942 .. He was next seen on October 22, 1942 complaining of "a catch in his back" and bilateral radiation of pain into both thighs anteriorly. There was a marked list of the lumbar spine to the right and straight leg raising was painful, especially on the left. He was readmitted to the hospital and improved rapidly with inductotherm treatments, being dismissed again four days later. However, he continued to complain of low back pain and has not been.able to work steadily. Spinal fusion has been advised but the patient has refused further surgery.
Comment.-This case is an example of an unsatisfactory result. Spinal fusion was certainly indicated in this case and should have been done at the operation for removal of the disk protrusion. The evidence at operation of extensive disk degeneration without any marked protrusion suggests that the protrusion was of relatively little importance and the pathologic change within the disk of chief importance. This patient's attitude and personality made him a poor choice for surgical treatment. He was pessimistic before operation about the likelihood of relief and he had a low· pain threshold with a tendency to exaggerate his complaints. For many years he had complained of a "weak stomach" with frequent gastric upsets, although repeated examinations by capable gastroenterologists had never revealed any organic cause for these disturbances. We would have done well not to have advised operation on this patient; if operated on he should have had a spinal fusion combined with removal of the disk protrusion. CASE IV.-J. N., a 35 year old grain broker, had had recurrent, low back pain for eight years, usually brought on by exercise and more frequent in the winter months. Extensive and prolonged orthopedic treatment had failed to give relief. For a week the pain had radiated down the posterior aspect of the right lower extremity and had been exacerbated by coughing or sneezing. The patient had been an active athlete in high school and college and had done heavy work during school vacations. He could not, however, give a history of a specific back strain or injury.
PROTRUSION OF THE INTERVERTEBRAL DISK
119
Examination revealed a moderately positive right Lasegue sign and definite lumbosacral tenderness. The right ankle jerk was diminished; there were no sensory changes. An air myelogram was carried out, 30 cc. of spinal fluid being removed and air substituted. The total protein content of the spinal fluid was 67 mg. The myelograms showed 11 defect in the air column on the right at the fourth lumbar interspace. Because of the minimal objective neurologic findings and the long history of low back pain, and with the case of M. N. in mind, further orthopedic consultation was advised. Dr. Perry Rogers saw the patient, concurred in the diagnosis of protrusion of an intervertebral disk and advised the combination of spinal fusion with removal of the
A
B
Fig. 32 (Case IV) .-A, Postoperative roentgenogram, anteroposterior view, six weeks after combined operation. B, Lateral view.
disk protrusion. The preoperative diagnosis was protrusion of the fourth intervertebral disk on the right. Operation on February 2, 1943 consisted of exposure .of the spines and laminae from the fourth lumbar to the second sacral vertebrae. The ligamentum flavUlP was widely resected at the fourth and fifth lumbar interspaces and a small portion of the adjacent laminae nibbled away. There was no evidence of disk protrusion at the fourth lumbar interspace. On the right, near the midline at the lumbosacral interspace, there was ·a large protrusion. The posterior longitudinal ligament was not ruptured but was so thin over the protrusion that it ruptured on gentle probing. A large amount of fragmented disk material was removed. The cavity in the disk after removal of the
120
HAROLD C. VORIS
fragmented material was 3 cm. deep. Dr. Rogers then performed a Hibbs' type spinal fusion, using plaques of bone from the outer table of the right ilium, in addition to slabs of bone from the spinous processes, the laminae, and the posterior aspect of the sacrum. Convalescence was uneventful. The patient was ambulatory in a body cast at the time of his dismissal on February 24, 1943. The cast was removed six weeks after operation. Figure 32 shows roentgenograms taken at that time. During the summer of 1943 he played tennis without ill effects. When last seen in May of 1944 he was perfectly well and was enjoying golf, badminton and tennis. CO'fJlment.- The result in this case is in marked contrast to that obtained in Case III with a comparable history. However, it would not be accurate to carry the comparison further. This patient was a much more stable individual-a very intelligent and highly successful business man who cooperated fully in his treatment. Moreover, he had a large protrusion of the disk which adequately accounted for his root pain. However, the very satisfactory result speaks well for the combined operation. It should be noted that the air myelogram not only failed to localize the lesion but was actually misleading, indicating a nonexistent protrusion at the fourth lumbar disk. Even at best air myelography is far inferior fr0111 a roentgenographic standpoint to lipiodol or pantopaque.
CASE V.-D. M., a 27 year old housewife, had strained her back nine months before while carrying her baby upstairs in its carriage. Low back pain followed and within a few days became severe, and right sciatic radiation was noted with numbness of the right buttock and posterior aspe.ct of the right thigh. The numbness had gradually improved but still persisted in considerable degree. She had been delivered of another child six months later but did not feel that her labor pains had been different from former labors or that labor had affected her low back or sciatic pain. The pain had been recurrent with every effort to resume normal activity. Examination revealed a moderately positively Lascgue sign on the right and absence of the right ankle jerk. There was marked hypesthesia to pinprick in the right side of the perineum and the posterior aspect of the right thigh (third to fifth sacral dermatomes). An air myelogram was done; 40 cc. of fluid were removed and air substituted. The total protein content of the spinal fluid was 50 mg. per 100 cc. The myelograms showed a shift of the air column to the left opposite the fifth lumbar interspace. A diagnosis was made of a large disk protrusion on the right at the lumbosacral level. Neoplasm was considered a possibility because of the involvement of sacral dermatomes.
PROTRUSION OF TB E INTERVERTEBRAL DISK
121
Operation on January 8, 1944 was a right hemilaminectomy of the fifth lumbar vertebra. Initially the ligamentum flavum was resected on the right at the fourth and fifth lumbar interspaces and the resultant opening then enlarged by nibbling away the adiacent laminae slightly with rongeurs. With this exposure no disk protrusion could be seen, hut after complete removal of the right si~ of the lamina of the fifth lumbar vertebra a protrusion of the lumbosacral disk could be visualized near the midline projecting upward so that it could not be seen through the interlaminar space. The posterior longitudinal ligament was not ruptured; after its incision a considerable amount of fragmented cartilage and nucleus pulposus was removed. Extradural bleeding was trouhlesome and finally required several muscle pledgets to control. Convalescence was uneventful and the patient left the hospital on January 24, 1944. The sensation in the right perineum, buttock and posterior thigh had improved, especially over the perineum and buttock. A month later no objective sensory disturbance could be found although subjective numbness of the posterior aspect of the right thigh was still present. The patient has not been seen since but reports by letter that she is entirely well.
Comment.-This patient's sciatic radiation began within a few days of her low back pain. The onset was related to a definite back strain. Unusual features were the early paresthesias in the sacral dermatomes and the objective sensory disturbances in these dermatomes on examination. This protrusion near the midline was apparently large from the onset so that sciatic radiation of pain and sensory di~turbances appeared very early. Some improvement had followed conservative treatment but she had been practically incapacitated from the time of her injury. She 'was six months' pregnant at the time of the onset but what role that played in the severity and persistence of her symptoms is difficult to assess. She noted no improvement after delivery. At operation this patient's disk protrusion could not be visualized through the usual interlaminar approach and complete hemilaminectomy of the fifth lumbar vertebra was necessary. Neurologic surgeons know that laminectomy, even if extensive, is not disabling nor does it weaken the spine if the articular facets are preserved. Other things being equal it is of course desirable to remove as little tissue and destroy normal relatio~ships as little as possible in the removal of a disk protrusion. This desire should not lead to the failure to visualize the protrusions or adequately remove them through lack of exposure. The surgeon should not operate unless he is convinced that a disk protrusion is present; if he does operate, while his initial exposure may be limited,
122
HAROLD C. VORIS
he should never fail to make an exposure adequate remove the obstruction.
tD
visualize and
GENERAL COMMENT
The History.-The importance of a good history cannot be over-
estimated. Root pain, whether in the sciatic radiation or elsewhere, has certain rather constant characteristics. When present its location is constant, it is often worse at night, and it is usually exacerbated by coughing, sneezing or muscular straining. The past history must be carefully inquired into for attacks of back pain or sciatica in the past and for back injury or strain. Examinaton.-On examination the patient may limp on the affected side if the pain is severe. Often the lumbar spine lists away from the affected side, occasionally to that side. Localized tenderness at the affected interspace is a frequent finding. Straight leg raising is almost always painful, sometimes extremely so. The absence or impairment of the ankle jerk on the affected side or some degree of sensory disturbance in the affected dermatome or dermatomes is exceedingly important. In my own experience such obj ective neurologic findings were absent in only 15 per cent of the cases in which a disk protrusion was found at operation. On the other hand, in the cases in which I failed to find a disk protrusion, such objective neurologic findings were never present. It is obvious from this that, in the absence of objective neurologic findings, great care should be exercised in making a diagnosis of protruded disk. Probably contrast myelography should be used in all of these cases. It must be emphasized that the objective neurologic findings referred to are minimal and must be sought for carefully and skillfully. Bradford and Spurling, and Semmes have well emphasized the importance of careful neurologic examination. . Selection of Patients for Operation.-The selection of patients for operation is very important. As has already been stated, many patients with mild symptoms can live fairly comfortably with their disk protrusion if they are brought through an occasional exacerbation of their symptoms by conservative treatment. This is particularly true of those individuals who are fortunate enough to be able and willing to avoid hard physical labor or strenuous exercise. Many patients with acute back strain have injury to the intervertebral disk and the annulus fibrosus or posterior longitudinal spinal ligament. However, with rest and perhaps temporary immobilization healing takes place and there is no recurrence of symptoms. Perhaps an improvement in the early management of low back injuries might lessen the incidence of later disk protrusions. In addition to those patients whose symptoms are not sufficiently marked to warrant surgical intervention, there is a group
PROTRUSIO~ OF THE INTERVERTEBRAL DISK
123
of patients who do have severe and disabling complaints. However, these individuals, because of their personality and attitude (Case Ill) are likely to continue to complain after an apparently successful operative procedure or they may develop a new set of complaints after operation. All surgeons know this type of patient and learn to avoid elective operative procedures on him whenever possible. Another group of patients with disk protrusions that is notoriously apt to obtain poor results from surgery consists of the compensatjon cases. Where it is feasible, the patient with a compensation problem should be encouraged to obtain a final settlement of his case and then seek relief from surgery. Such settlement should of course take into account his prospective medical and hospital expense. When surgery is carried out while the patient is still receiving compensation, the patient should be told frankly that after operation he will be expected gradually to resume full activity and finally return to work even at the expense of minor discomfort. Patients in this group with low pain thresholds, inadequate personalities, or who indicate resentment against their employer or the insurance carrier will seldom obtain a good result, at least during the period of compensation. The patient who has legal proceedings pending, either in court or before the Industrial Board, will seldom cease to complain until after these proceedings have been settled. Patients who do require operation fall into three main groups. Those in the first group have relatively mild symptoms but circumstances or the patient's own desires (Case IV) demand considerable physical activity and the persistent recurrence of symptoms finally brings them to operation. If they can change their occupation or if they will give up strenuous exercise, an operation may be avoided. Many cannot do the former; some refuse the latter alternative. Selection of cases must be carried out carefully in this group. A second group in spite of conservative treatment and limitation of activity continues to have recurrence of pain and also finally comes to operation (Case I). Patients in this group present fewer problems than the first group. Trial of conservative treatment has been adequate and the patient has been cooperative. The persistence of recurrences under such conditions warrants surgical intervention. Finally there is a group of patients whose pain is constant and severe with any activity (Case V) or who develop marked objective neurologic disability (Case Il). These patients present an absolute indication for operation because of their disability and suffering. Once the diagnosis is established, and in this group that is usually not difficult, surgery is indicated.
124
HAROLD C. VORIS
•
Surgical Management.-The surgical removal of a disk protrusion, especially through a limited exposure, requires an accurate anatomical knowledge of the region involved plus certain special instruments and technic. The management of epidural bleeding is often troublesome, interfering with the exposure and removal of the lesion. If it is not controlled before the closure of the wound, postoperative hematoma with serious neurologic sequelae may occur. The use of suction and electrocoagulation is of great help. Small implants of muscle or, as recently suggested by Ingraham, Bailey and Nulsen, of pieces of fibrin foam soaked in thrombin may Le necessary. Small cottonoid strips, cotton pledgets, special nerve root retractors, special rongeurs and hiopsy punches are all of great assistance and represent part of the regular armamentarium of the neurologic surgeon. The most debated question in the surgical management of these cases is that of whether spir/al fusioll should be combined with removal of the disk protrusion-the so-called "combined operation." Opinions vary from the extreme that it should be done in every case of disk protrusion, to the other extreme, that it is seldom if ever necessary. Only time and further observation of the results in large numbers of cases can give the answer. For the present it is my opinion that the combined operation should be considered (1) in cases of multiple or recurrent disk protrusions, (2) where there is roentgenographic, clinical or surgical evidence of inherent instability of the lumbosacral spine, (3) where low back pain is severe and disabling for a long period before the onset of sciatic radiation, and (4) where the patient's occupation is one of heavy labor or demands a great deal of lifting. Obviously the best interests of the patient are served by the full cooperation of neurologic and orthopedic surgeons, and it is no accident that the most advances and the best results in the management of these cases have come from those clinics and institutions where such cooperation is routine and where both the neurologic and orthopedic surgeons have contributed their share to the problem. Postoperative Management.-The length of time that a patient should spend in bed after the operation and the period of convalescence before returning to full activity are in my opinion very important points. Since any operative repair of the rupture of the posterior longitudinal spinal ligament or annulus fibrosus is not technically feasible, we are forced to depend on natural means-the proliferation of fibrous connective (scar) tissue-for the repair of these structures and the cavity in the disk left by the removal of fragmented nucleus pulposus and fibrocartilage. It is our practice to keep the patient in bed for two
PROTRUSION OF THE INTERVERTEBRAL DISK
125
weeks after the removal of a disk protrusion and then allow gradual resumption of activity. Light work may be resumed in six weeks; full physical activity, especially heavy lifting or strenuous work, should be postponed for three months. Some will object to this, claiming that such long periods of inactivity tend to destroy the patient's confidence in the result and to increase the number of patients with poor results. It is true, especially in compensation cases, that every effort should be made to discourage the development of an attitude of chronic invalidism. However, if an adequate explanation is given the patient for the prolonged convalescence and if, after the prescribed period has passed, firm insistence is made on resumption of activity, no serious difficulty should be encountered. Too often a surgeon fails to exercise adequate observation Of control of the patient's activity during convalescence and is then disappointed at the patient's refusal to undertake immediate full activity. BIBLIOGRAPHY
J. S.: Sciatica Caused by Intervertebral Disks. J. Bone & Joint Surg., 19:323-342, 1937. 2. Bradford, F. K. and Spurling, R. G.: The Intervertebral Disk. Springfield, Ill., Charles C Thomas, 158 pp., 1941. 3. Dandy, W. E.: Loose Cartilage from Intervertebral Disk Simulating Tumor of Spinal Cord. Arch. Surg., 19:660-672, 1929. 4. French, S. D. and Payne, J. T.: Cauda Equina Compression Syndrome with Herniated Nucleus Pulposus. Ann. Surg., 120:73-87, 1944. 5. Ingraham, F. D., Bailey, O. T. and Nulsen, F. E.: Studies on Fibrin Foam as a Hemostatic Agent in Neurosurgery, with Special Reference to Its Comparison with Muscle. J. Neurosurg., 1:171-182, 1944. 6. Love, J. G. and Walsh, M. N.: Protruded Intervertebral Disks. Surg., Gynec. & Obst., 77:497-509, 1943. 7. Roofe, P. G.: Innervation of Annulus Fibrosus and Posterior Longitudinal Ligament: Fourth and Fifth Lumbar Level. Arch Neuro!. & Psychiat., 44:100-103, 1940. H. Semmes, R. E., Diagnosis of Ruptured Intervertebral Disk without Contrast Myelography, and Comment upon Recent Experience with Modified Hemilaminectomy for Their Removal. Yale J. Bio!. & Med., 11:433-437, 1939. 9. Semmes, R. E. and lHurphy, F.: The Syndrome of Unilateral Rupture of the Sixth Cervical Intervertebral Disk with Compression of the Seventh Cervical Nerve Roots. J.A.M.A., 121:1209-1215, 1943. 10. Spurling, R. G. and Grantham, E. G.: Neurologic Picture of Herniations of the Nucleus Pulposus in the Lower Part of the Lumbar Region. Arch. Surg., 40:375-388, 1940. 1. Barr,