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Disc compression of the eighth cervical nerve: Pseudo ulnar palsy
Disc Compression of the Eighth Cervical Nerve: Pseudo Ulnar Palsy David Wallace, F.R.A.C.S., F.R.C.S.
Seventeen cases of compression of the eighth cervical nerve root are reported, with a discussion of the symptomatology, findings, and treatment. It would appear that this condition is not as rare as it was once thought to be. Wallace D: Disc compressionof the eighth cervical nerve: pseudoulnar palsy. SurgNeurol 18:295-299, 1982 Disc ruptures of the disc Sp~Lceat the cervicothoracic junction are said to be unusual [2, 3]. They are probably not so uncommon but often go unrecognized. Over a two-year period, I encountered 17 cases in an adult public and private neurosurgical practice. Ten patients were treated conservatively, and in the remaining 7 the diagnosis was proved at operation. Sometimes the neurological picture superficially resembled an ulnar nerve palsy.
Weakness was a symptom in all cases, but, not infrequently, patients were quite vague about such symptoms as weakness in the arm or hand or a weak grip. In one instance a medical practitioner had to give up assisting at surgical operations because he had a poor grip that made it difficult for him to hold a retractor. One patient had a proprioceptive defect. This patient, who was a surgeon, noted that he had to watch his fingers to know accurately where they were in space.
Findings on Examination Often patients were noted to be in severe pain. Neck movement was sometimes normal, but there was often limitation of neck movement, particularly extension; however, lateral flexion, rotation, and flexion were also affected. Clawing of the hand with differential flexion of the Symptomatology fingers, maximal in the little finger and minimal in the Pain was the most common symptom and the usual pre- index finger, was often noted. Superficially this resembled "ulnar clawing," but it was different in that there was senting complaint. The on,;et was insidious in 1 patient, but was usually sudden following a neck injury or a lifting flexion of the metacarpophalangeal joints. Wasting, when seen, was present in the triceps and inaccident. It was usually described as a nagging, dragging and continuous dull ache, with exacerbations. At times it terosseous muscles. There was a characteristic and consiswas very severe or totally incapacitating. Sometimes there tent pattern of weakness, with mild to moderate weakness was acute pain upon coughing, sneezing, straining at the of the triceps and of the long finger flexors and extensors toilet, or vomiting. Occasionally there was a postural ele- maximally affecting the fifth finger with minimal involvement, with certain postures of the neck bringing relief or ment of the index finger. There was mild to severe weakcausing exacerbation. Neck: extension or lateral flexion ness of the interosseous, thenar, and hypothenar muscles. There was altered sensation in the eighth cervical derseemed to be particularly aggravating. The sites of the pain were the low cervical area (though not all patients com- matome, which involved the sensory distribution of the plained of neck pain), the periscapular and rhomboid re- ulnar nerve in the hand and extended along the medial half gions, the shoulder, the upper arm muscles, and along the of the forearm on its anterior and posterior aspects to the ulnar side of the forearm arLd hand. Several patients had elbow. The triceps jerk was often reduced, but not to the pectoral muscle pain. extent usually seen with a lesion of the seventh cervical Paresthesias were frequently present in the distribution of nerve in which the reflex is often severely depressed or the eighth cervical nerve, e~-tending from the ulnar nerve absent. distribution in the medial half of the elbow, and were deImportant positive findings were impaired movement of scribed in various ways, including "pins and needles," "tin- the neck, weakness of the triceps, sensory loss extending gling," "dead feeling," and "numbness." above the wrist, and involvement of all thenar muscles. These findings are not present in an ulnar nerve palsy. Important negative findings were the absence of a From the Royal Melbourne Hospital, Melbourne, Australia. Homer's syndrome and no sensory loss in the first thoracic Address reprint requests to Mr. David Wallace, Suite 16, Private Consuiting Room, Royal Melbourne Hospital, Grattan St.. Parkville, Mel- nerve distribution which, if present, hint toward a Panbourne, Victoria, Australia. coast's tumor. Other important negative findings are the Key words: disc rupture, cervicothoracicjunction; eighth cervical nerve absence of a subclavian bruit and a negative Adson's maroot; pseudo ulnar palsy. neuver, both of which may be found with compression of 0090-3019/82/100295-05501.25 O 1982 by Little, Brown and Company (Inc.)
295
296 SurgicalNeurology Vol 18 No 4 October 1982
the eighth cervical and first thoracic nerves and with compression of the subclavian artery in the thoracic outlet syndrome. Plain x-ray films of the cervical spine were usually normal but sometimes showed a narrowed disc space between the seventh cervical and first thoracic vertebrae, which is of dubious diagnostic significance since this space is normally narrower than the space above. Cervical positive-contrast myelography was performed on all patients underoing surgery and was positive in all patients but one, showing truncation of the eight cervical nerve root sheath. In all patients in whom spinal fluid was obtained at myelography, the protein content of the cerebrospinal fluid was mildly increased.
Treatment
Conservative Rest, avoidance of heavy lifting and neck twisting, the wearing of a cervical collar, analgesics, and gentle physiotherapy were all helpful on occasions in tiding a patient over an attack. Cervical traction using a harness may also be helpful.
Table 1. Surgical Cases: Summary of Patients' Features Patient No.
Sex/Age (yr)
Onset of Pain
1 2 3
M/52 M/58 M/55
4 5 6 7
M/66 M/42 M/55 M/34
Rotational neck injury Yawning and stretching Neck extension and rotation Spontaneous Whiplash Insidious Lifting in flexed position
was evident within a month of commencing treatment in 3 patients, within 2 months in 2, and within 7 months in the remaining patient. I am aware of other instances in which improvement in mild cases commenced as late as 2 years after the onset of symptoms, with a good eventual outcome. These were cases that, in view of the minimal abnormalities present, warranted a prolonged conservative treatment.
Surgical Group Surgical Decompression of the affected nerve root by cervical foraminotomy afforded rapid relief from pain and recovery of power and sensation. When technically safe to do so, it was beneficial to remove the prolapsed disc, but this was not attempted if the nerve root was firmly adherent. The most rapid and dramatic postoperative recoveries occurred when the fragment of the ruptured disc had been removed, but gratifying and rapid recovery still occurred when decompression alone was performed.
Results
Conservative Group Of the 10 patients in this group, the onset of pain was unrelated to any physical insult in 2. In 1 patient, symptoms began acutely when the neck was extended to look upwards. Two patients developed symptoms after hyperextension injuries of the spine occurring in traffic accidents. Two patients developed symptoms after episodes which involved pulling a heavy weight, and 2 patients developed symptoms after lifting. The remaining patient developed his symptoms after a fall. The clinical features of the conservative group were quite similar to those found in the surgical group (see Tables 1 through 5). The results of treatment were as follows. Two patients were not followed; one had been referred for a legal consultation only and another had been referred for a second opinion. The 2 whiplash patients had no improvement by 4 months and 14 months but did not wish to undergo surgery. In 6 patients unquestionable improvement occurred, which
The clinical features of the surgically treated patients are outlined in Tables 1 through 5. Patient 2 experienced his first attack of brachial neuralgia while yawning. Patient 4 was awakened by severe left-sided pain that radiated into the pectoral muscles, associated with tingling. He was admitted to the hospital with a diagnosis of myocardial infarction. In most instances, surgical treatment was undertaken after conservative measures had failed. However, Patient 1 required urgent surgical treatment because of the severity of his pain; he had made arrangements to commit suicide if his initial consultation with me proved unfruitful. In the first six of his previous seven consultations he had been told that his symptoms were nonorganic; it was the seventh practitioner he saw who referred him for neurosurgical treatment of a suspected ulnar nerve lesion. The operation performed in each case was cervical foraminotomy done with the patient in the lateral position with the affected side uppermost. The lateral portion of the contiguous laminae and the bony roof of the intervertebral foramen were removed with a dental drill or rongeurs until the nerve root could be adequately visualized and decompressed. When ruptured disc fragments were removed, this was accomplished by gently retracting the nerve root and removing disc fragments from anterior to the axilla or the shoulder of the nerve root. In 4 instances bony decompression alone was performed because of firm adherence of the disc to the nerve root. The dural nerve sheath was not opened. The results of surgery (Table 5) were very gratifying in this small series, with rapid relief of brachial neural-
Wallace: Compression of Eighth Cervical Nerve Root
297
Table 2. Surgical Cases: Summary of Symptoms Pain Patient No.
Neck
Scapula
A r m and Fingers
Chest
Acute
Weakness
Numbness
1 2 3
+ + -
+ + +
+ + +
-
+ -
+ + +
+ + +
4 5 6
+ -
+ + +
+ + +
+ +
+ -
+ + +
+ + +
7
+
+
+
+
+
+
+
+ =yes; - = no.
Table 3. Operative Findings Patient No.
Restricted Neck Movement
Weakness ~ Triceps
EDL
Wasting
Intrinsics
FDP
Triceps
Intrinsics
Triceps Jerk
C8 Sensory Loss
Claw Hand
1
+
+
+
+
+
+
+
,[,
+
+
2 3
+ +
4+
+ +
+ +
+ +
+ -
-
$ $
+ +
+ +
4 5 6 7
+ + +
4+ + +
+ + +
+ + + +
+ + + +
-
+ -
$ ~ ~, $
+ + + +
+ + +
aln all cases there was weakness of the extensor digitomm longus and flexor digitomm profundus muscles, maximal in the fifth finger and minimal in the index. EDL = extensor digitomm longu~,; FDP = flexor digitorum profundus; + = yes; - = no; ~, = reduced.
Table 4. Investigations in Surgical Cases Patient No.
CSF Protein (mg/liter) a
Plain Roentgenogmms
gia a n d w i t h full r e c o v e r y o f s e n s a t i o n a n d i m p r o v e d m u s c l e s t r e n g t h i n all p a t i e n t s . Myelograms
Differential D i a g n o s i s of Eighth Cervical N e r v e Lesion 1
614
Negative
2
. . .
3
490
Degenerative changes, narrow discs (C5.6, C6-7) Cervical spondylosis
< 400 (normal) 960 400
Mild degenerative changes Negative
Negative aNormal level: 150 to 450 mg/liter.
Cut-off C8 nerve sheath Bilateral C8 cut-off
Bilateral C8 cut-off (left > right) C8 cut-off Negative Cut-off C8 nerve sheath Cut-off C8 nerve sheath
Ulnar Nerve Lesion The patient with a pure ulnar nerve lesion has no neck s y m p t o m s or s c a p u l a r p a i n , t h e s e n s o r y loss is c o n f i n e d to t h e h a n d , a n d t h e r e is n o i n v o l v e m e n t of t h e triceps or finger e x t e n s o r s , or o f t h e a b d u c t o r pollicis brevis m u s c l e .
Cervical Rib-Thoracic Outlet Syndrome The cervical rib-thoracic outlet syndrome may be quite difficult to d i s t i n g u i s h s i n c e t h e e i g h t h c e r v i c a l n e r v e m a y b e i n v o l v e d i n t h i s s y n d r o m e . P a t i e n t 5 h a d i n fact u n d e r g o n e a n e x p l o r a t i o n of t h e left t h o r a c i c o u t l e t a t a n o t h e r i n s t i t u t i o n 6 years b e f o r e h i s c e r v i c a l f o r a m i n o t o m y , w i t h o u t a n y relief. S y m p t o m s of v a s c u l a r o c c l u s i o n , s u c h as coldness of t h e h a n d s a n d s y m p t o m s of v a s o s p a s m , m a y h i n t a t t h e p r e s e n c e of a c e r v i c a l rib, as m a y a s u b c l a v i a n b r u i t a n d a p o s i t i v e A d s o n ' s m a n e u v e r . P l a i n x-ray films of t h e s p i n e will s h o w t h e p r e s e n c e o f i n c o m p l e t e c e r v i c a l ribs or large, d o w n - p o i n t i n g t r a n s v e r s e processes of t h e s e v e n t h c e r v i c a l
298
Surgical Neurology Vol 18 No 4 October 1982
Table 5. Operative Details and Resultsa Patient No.
Date of Operation
1
10/14/77
2
9/5/78
3
10/3/78
4
7/16/79
5
11/13/79
6
7/4/80
7
8/19/80
Results Operation
Pain
Strength
C8 compression, large disc and 3 large fragments removed Large disc removed, C8 compression C8 compression, adherent disc, bony decompression C8 compression, vascular and adherent disc
Relieved
Normal by 11/9/77 Normal
Suicidal preoperatively
Relieved
Full return
Normal
Simple onset (yawning)
Relieved
Minimal residual weakness
Normal
Relieved
Minimal residual weakness
Normal
Relieved
Minimal triceps weakness only
Normal
Relieved
Full recovery
Normal
Rapid relief
Greatly improved
Normal
Very lateral disc rupture, disc adherent to C8 dural sheath C8 compression by adherent scarred, ruptured disc (decompression only) C8 compression by soft ruptured disc
Sensation
Comments
Very lateral disc, pure C8 lesion producing weakness in intrinsic muscles Very lateral disc, pure C8 lesion producing weakness in intrinsic muscles
~Operation: cervicalforaminotomy(C7-T1 level)•
vertebra, and subclavian arteriography may show stenosis or occlusion of the artery on abduction and external rotation of the arm. The associated involvement of the first thoracic nerve will also help in making this diagnosis.
finger. The distribution of the sensory loss is within the distribution of the seventh cervical nerve, with maximal involvement usually noted in the index finger and with extension along the lateral aspect of the forearm.
Pancoast's Tumor
First Thoracic Nerve Lesion
If there is a history of a previous neoplasm of the lung, a Pancoast's tumor may be suspected. Involvement of the eighth cervical nerve in this condition is usually accompanied by involvement of the first thoracic nerve and Homer's syndrome. Apical chest x-ray films and studies of the first rib may show evidence of neoplasia.
There is usually no clinical involvement of the triceps, extensor digitorum longus, or the flexor digitorum profundus muscles in cases of first thoracic nerve lesions. The sensory loss is in the distribution of the first thoracic nerve along the medial aspect of the upper arm from the elbow to the axilla, but the intrinsic muscle involvement can be identical. There may be an accompanying Homer's syndrome.
Myocardial Infarction When rupture of a disc involves the left eighth cervical nerve, as may also occur with a left seventh cervical nerve lesion, pain in the neck associated with pain in the arm and upper chest may lead to a mistaken diagnosis of myocardial infarction. Patient 1 was admitted to a coronary intensive care unit because of these symptoms, and Patient 7 was admitted to a medica ! ward with this diagnosis.
Seventh Cervical Nerve Lesion With involvement of the seventh cervical nerve there is lao involvement of the intrinsic muscles of the hand; the triceps involvement tends to be more pronounced and the triceps jerk more affected. The finger extensors are more diffusely involved, with maximal involvement of the index
Discussion Modem anatomical texts have contained such statements as: "Clinical observations indicate that all the small muscles of the hand receive their motor innervation from TI" [1]. It is clear from this study that the motor supply of the intrinsic hand muscles is not exclusively innervated by the first thoracic nerve. In Patients 4 and 5, the prolapse of the disc contacted the eighth cervical nerve quite lateral to the main cervical theca and did not simultaneously compress the first thoracic nerve. Both patients had obvious intrinsic weakness, and Patient 5 had muscle wasting as well. Eighth cervical nerve lesions may be mistaken for ulnar nerve lesions, lesions of the seventh cervical or first thoracic nerves, or myocardial infarction. Accurate diag-
Wallace: Compression of Eighth Cervical Nerve Root
nosis is essential if correct treatment is to be undertaken, and particularly if surgery is indicated. Lesions of the eighth cervical nerve may lead to clawing of the hand that superficially resembles ulnar clawing. I presume it occurs because of differential and graded innervation of the flexor digitorum profundus and extensor digitorum longus muscles to the fingers, with maximal innervation of the eighth cervical nerve to the fifth finger and minimal innervation to the: first finger. The cases of Patients 4 and 5 illustrate that nerve root compression can occur quite laterally, and in Patient 5 the myelogram was normal, though the cerebrospinal fluid protein level was high. ~ l a e n there is a strong clinical impression of a pure eighth cervical nerve lesion, the symptoms are severe and prolonged, and the myelogram is negative, consideration should be given to an exploratory operation. Patient 5, a general practitioner, suffered severe pain and underwent several years of psychiatric treatment for his pain and associated depression, which were engendered by prolapse of his disc. Surgical relief was further delayed by his negative myelogram, and during this delay he
299
developed renal disease due to the psychotropic drugs he was taking. Because of the limited amount of movement that occurs at the disc space between the seventh cervical and first thoracic vertebrae, neck movement may be normal in range and free of pain. In view of the findings in this series, it would appear that lesions of the eighth cervical nerve are probably not very rare, but are poorly recognized by practitioners, within and without the neurosurgical profession. My thanks to Mr. David Brownbill for referring Patient 4, and to Mrs. Maureen Kerriganfor typing the manuscript. References 1. Johnston TB, Davies DV, Davies F (eds): Gray's Anatomy, ed 32. London: Longmans, Green, 1958, p 652 2. LunsfordLD, Bissonette DJ, Jannetta PJ, Sheptak PE, Zomb DS: Anterior surgeryfor cervicaldisc disease. Part 1: Treatment of lateral cervical disc herniation in 253 cases. J Neurosurgery53:1-11, 1980 3. Northfield D: The Surgery of the Central Nervous System. Oxford: Blackwell, 1973, p 734
Book Review Tissue Fluid Pressure and Composition Edited by Alan R. Hargens Baltimore, Williams & Wilkins, 1981 275 pp., $34.00
Reviewed by Michael J. Rosner, M.D., Richmond, Virginia Dr. Hargens has edited a volume which constitutes a micro course in the study techniques, controversies, and applications of tissue fluid pressure measurements. The volume begins with introductory chapters dealing with what, to the uninitiated reader, appears to be a simple problem: to evaluate and measure tissue pressure. He quickly reveals the difficulty of the task. The major opposing theoretical orientations are discussed. Throughout, the prose is clear and concise. From the point of view of the neuroscientist interested in tissue pressures in the central and peripheral nervous systems, this volume is modera~:ely deficient. However, it certainly functions well as a basic introduction to the different techniques of tissue pressure measurement and the controversies inherent in each technique.
There are several chapters dealing with muscle and connective tissue. Two early chapters (9 and 10) deal with reasonably basic mechanisms of edema prevention/ formation and lymph flow, and they are nicely balanced by three clinically related chapters (21, 22, and 26). Pulmonary physiology and tissue pressure are well covered by three chapters. Three chapters (15, 17, and 18) are devoted to the obviously important topic of fluid and lymph flow in the bowel and mesentery. Tissue Fluid Pressure and Composition serves as a readable and concise introduction to the problem. The basic theoretical mathematics, chemistry, physical chemistry, and hydrodynamics are clearly reviewed and placed in the context of the difficulty of measurement and its attendant experimental controversies. Subsequent chapters introduce tissue pressure measurement as it relates to several organ systems in both normal and pathological states. Ultimately, the reader may be disappointed by the lack of a final and clear resolution to the many controversies introduced, but that is the price of a "state of the art" text.
Seventeen cases of compression of the eighth cervical nerve root are reported, with a discussion of the symptomatology, findings, and treatment. It would appear that this condition is not as rare as it was once thought to be. Wallace D: Disc compressionof the eighth cervical nerve: pseudoulnar palsy. SurgNeurol 18:295-299, 1982 Disc ruptures of the disc Sp~Lceat the cervicothoracic junction are said to be unusual [2, 3]. They are probably not so uncommon but often go unrecognized. Over a two-year period, I encountered 17 cases in an adult public and private neurosurgical practice. Ten patients were treated conservatively, and in the remaining 7 the diagnosis was proved at operation. Sometimes the neurological picture superficially resembled an ulnar nerve palsy.
Weakness was a symptom in all cases, but, not infrequently, patients were quite vague about such symptoms as weakness in the arm or hand or a weak grip. In one instance a medical practitioner had to give up assisting at surgical operations because he had a poor grip that made it difficult for him to hold a retractor. One patient had a proprioceptive defect. This patient, who was a surgeon, noted that he had to watch his fingers to know accurately where they were in space.
Findings on Examination Often patients were noted to be in severe pain. Neck movement was sometimes normal, but there was often limitation of neck movement, particularly extension; however, lateral flexion, rotation, and flexion were also affected. Clawing of the hand with differential flexion of the Symptomatology fingers, maximal in the little finger and minimal in the Pain was the most common symptom and the usual pre- index finger, was often noted. Superficially this resembled "ulnar clawing," but it was different in that there was senting complaint. The on,;et was insidious in 1 patient, but was usually sudden following a neck injury or a lifting flexion of the metacarpophalangeal joints. Wasting, when seen, was present in the triceps and inaccident. It was usually described as a nagging, dragging and continuous dull ache, with exacerbations. At times it terosseous muscles. There was a characteristic and consiswas very severe or totally incapacitating. Sometimes there tent pattern of weakness, with mild to moderate weakness was acute pain upon coughing, sneezing, straining at the of the triceps and of the long finger flexors and extensors toilet, or vomiting. Occasionally there was a postural ele- maximally affecting the fifth finger with minimal involvement, with certain postures of the neck bringing relief or ment of the index finger. There was mild to severe weakcausing exacerbation. Neck: extension or lateral flexion ness of the interosseous, thenar, and hypothenar muscles. There was altered sensation in the eighth cervical derseemed to be particularly aggravating. The sites of the pain were the low cervical area (though not all patients com- matome, which involved the sensory distribution of the plained of neck pain), the periscapular and rhomboid re- ulnar nerve in the hand and extended along the medial half gions, the shoulder, the upper arm muscles, and along the of the forearm on its anterior and posterior aspects to the ulnar side of the forearm arLd hand. Several patients had elbow. The triceps jerk was often reduced, but not to the pectoral muscle pain. extent usually seen with a lesion of the seventh cervical Paresthesias were frequently present in the distribution of nerve in which the reflex is often severely depressed or the eighth cervical nerve, e~-tending from the ulnar nerve absent. distribution in the medial half of the elbow, and were deImportant positive findings were impaired movement of scribed in various ways, including "pins and needles," "tin- the neck, weakness of the triceps, sensory loss extending gling," "dead feeling," and "numbness." above the wrist, and involvement of all thenar muscles. These findings are not present in an ulnar nerve palsy. Important negative findings were the absence of a From the Royal Melbourne Hospital, Melbourne, Australia. Homer's syndrome and no sensory loss in the first thoracic Address reprint requests to Mr. David Wallace, Suite 16, Private Consuiting Room, Royal Melbourne Hospital, Grattan St.. Parkville, Mel- nerve distribution which, if present, hint toward a Panbourne, Victoria, Australia. coast's tumor. Other important negative findings are the Key words: disc rupture, cervicothoracicjunction; eighth cervical nerve absence of a subclavian bruit and a negative Adson's maroot; pseudo ulnar palsy. neuver, both of which may be found with compression of 0090-3019/82/100295-05501.25 O 1982 by Little, Brown and Company (Inc.)
295
296 SurgicalNeurology Vol 18 No 4 October 1982
the eighth cervical and first thoracic nerves and with compression of the subclavian artery in the thoracic outlet syndrome. Plain x-ray films of the cervical spine were usually normal but sometimes showed a narrowed disc space between the seventh cervical and first thoracic vertebrae, which is of dubious diagnostic significance since this space is normally narrower than the space above. Cervical positive-contrast myelography was performed on all patients underoing surgery and was positive in all patients but one, showing truncation of the eight cervical nerve root sheath. In all patients in whom spinal fluid was obtained at myelography, the protein content of the cerebrospinal fluid was mildly increased.
Treatment
Conservative Rest, avoidance of heavy lifting and neck twisting, the wearing of a cervical collar, analgesics, and gentle physiotherapy were all helpful on occasions in tiding a patient over an attack. Cervical traction using a harness may also be helpful.
Table 1. Surgical Cases: Summary of Patients' Features Patient No.
Sex/Age (yr)
Onset of Pain
1 2 3
M/52 M/58 M/55
4 5 6 7
M/66 M/42 M/55 M/34
Rotational neck injury Yawning and stretching Neck extension and rotation Spontaneous Whiplash Insidious Lifting in flexed position
was evident within a month of commencing treatment in 3 patients, within 2 months in 2, and within 7 months in the remaining patient. I am aware of other instances in which improvement in mild cases commenced as late as 2 years after the onset of symptoms, with a good eventual outcome. These were cases that, in view of the minimal abnormalities present, warranted a prolonged conservative treatment.
Surgical Group Surgical Decompression of the affected nerve root by cervical foraminotomy afforded rapid relief from pain and recovery of power and sensation. When technically safe to do so, it was beneficial to remove the prolapsed disc, but this was not attempted if the nerve root was firmly adherent. The most rapid and dramatic postoperative recoveries occurred when the fragment of the ruptured disc had been removed, but gratifying and rapid recovery still occurred when decompression alone was performed.
Results
Conservative Group Of the 10 patients in this group, the onset of pain was unrelated to any physical insult in 2. In 1 patient, symptoms began acutely when the neck was extended to look upwards. Two patients developed symptoms after hyperextension injuries of the spine occurring in traffic accidents. Two patients developed symptoms after episodes which involved pulling a heavy weight, and 2 patients developed symptoms after lifting. The remaining patient developed his symptoms after a fall. The clinical features of the conservative group were quite similar to those found in the surgical group (see Tables 1 through 5). The results of treatment were as follows. Two patients were not followed; one had been referred for a legal consultation only and another had been referred for a second opinion. The 2 whiplash patients had no improvement by 4 months and 14 months but did not wish to undergo surgery. In 6 patients unquestionable improvement occurred, which
The clinical features of the surgically treated patients are outlined in Tables 1 through 5. Patient 2 experienced his first attack of brachial neuralgia while yawning. Patient 4 was awakened by severe left-sided pain that radiated into the pectoral muscles, associated with tingling. He was admitted to the hospital with a diagnosis of myocardial infarction. In most instances, surgical treatment was undertaken after conservative measures had failed. However, Patient 1 required urgent surgical treatment because of the severity of his pain; he had made arrangements to commit suicide if his initial consultation with me proved unfruitful. In the first six of his previous seven consultations he had been told that his symptoms were nonorganic; it was the seventh practitioner he saw who referred him for neurosurgical treatment of a suspected ulnar nerve lesion. The operation performed in each case was cervical foraminotomy done with the patient in the lateral position with the affected side uppermost. The lateral portion of the contiguous laminae and the bony roof of the intervertebral foramen were removed with a dental drill or rongeurs until the nerve root could be adequately visualized and decompressed. When ruptured disc fragments were removed, this was accomplished by gently retracting the nerve root and removing disc fragments from anterior to the axilla or the shoulder of the nerve root. In 4 instances bony decompression alone was performed because of firm adherence of the disc to the nerve root. The dural nerve sheath was not opened. The results of surgery (Table 5) were very gratifying in this small series, with rapid relief of brachial neural-
Wallace: Compression of Eighth Cervical Nerve Root
297
Table 2. Surgical Cases: Summary of Symptoms Pain Patient No.
Neck
Scapula
A r m and Fingers
Chest
Acute
Weakness
Numbness
1 2 3
+ + -
+ + +
+ + +
-
+ -
+ + +
+ + +
4 5 6
+ -
+ + +
+ + +
+ +
+ -
+ + +
+ + +
7
+
+
+
+
+
+
+
+ =yes; - = no.
Table 3. Operative Findings Patient No.
Restricted Neck Movement
Weakness ~ Triceps
EDL
Wasting
Intrinsics
FDP
Triceps
Intrinsics
Triceps Jerk
C8 Sensory Loss
Claw Hand
1
+
+
+
+
+
+
+
,[,
+
+
2 3
+ +
4+
+ +
+ +
+ +
+ -
-
$ $
+ +
+ +
4 5 6 7
+ + +
4+ + +
+ + +
+ + + +
+ + + +
-
+ -
$ ~ ~, $
+ + + +
+ + +
aln all cases there was weakness of the extensor digitomm longus and flexor digitomm profundus muscles, maximal in the fifth finger and minimal in the index. EDL = extensor digitomm longu~,; FDP = flexor digitorum profundus; + = yes; - = no; ~, = reduced.
Table 4. Investigations in Surgical Cases Patient No.
CSF Protein (mg/liter) a
Plain Roentgenogmms
gia a n d w i t h full r e c o v e r y o f s e n s a t i o n a n d i m p r o v e d m u s c l e s t r e n g t h i n all p a t i e n t s . Myelograms
Differential D i a g n o s i s of Eighth Cervical N e r v e Lesion 1
614
Negative
2
. . .
3
490
Degenerative changes, narrow discs (C5.6, C6-7) Cervical spondylosis
< 400 (normal) 960 400
Mild degenerative changes Negative
Negative aNormal level: 150 to 450 mg/liter.
Cut-off C8 nerve sheath Bilateral C8 cut-off
Bilateral C8 cut-off (left > right) C8 cut-off Negative Cut-off C8 nerve sheath Cut-off C8 nerve sheath
Ulnar Nerve Lesion The patient with a pure ulnar nerve lesion has no neck s y m p t o m s or s c a p u l a r p a i n , t h e s e n s o r y loss is c o n f i n e d to t h e h a n d , a n d t h e r e is n o i n v o l v e m e n t of t h e triceps or finger e x t e n s o r s , or o f t h e a b d u c t o r pollicis brevis m u s c l e .
Cervical Rib-Thoracic Outlet Syndrome The cervical rib-thoracic outlet syndrome may be quite difficult to d i s t i n g u i s h s i n c e t h e e i g h t h c e r v i c a l n e r v e m a y b e i n v o l v e d i n t h i s s y n d r o m e . P a t i e n t 5 h a d i n fact u n d e r g o n e a n e x p l o r a t i o n of t h e left t h o r a c i c o u t l e t a t a n o t h e r i n s t i t u t i o n 6 years b e f o r e h i s c e r v i c a l f o r a m i n o t o m y , w i t h o u t a n y relief. S y m p t o m s of v a s c u l a r o c c l u s i o n , s u c h as coldness of t h e h a n d s a n d s y m p t o m s of v a s o s p a s m , m a y h i n t a t t h e p r e s e n c e of a c e r v i c a l rib, as m a y a s u b c l a v i a n b r u i t a n d a p o s i t i v e A d s o n ' s m a n e u v e r . P l a i n x-ray films of t h e s p i n e will s h o w t h e p r e s e n c e o f i n c o m p l e t e c e r v i c a l ribs or large, d o w n - p o i n t i n g t r a n s v e r s e processes of t h e s e v e n t h c e r v i c a l
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Surgical Neurology Vol 18 No 4 October 1982
Table 5. Operative Details and Resultsa Patient No.
Date of Operation
1
10/14/77
2
9/5/78
3
10/3/78
4
7/16/79
5
11/13/79
6
7/4/80
7
8/19/80
Results Operation
Pain
Strength
C8 compression, large disc and 3 large fragments removed Large disc removed, C8 compression C8 compression, adherent disc, bony decompression C8 compression, vascular and adherent disc
Relieved
Normal by 11/9/77 Normal
Suicidal preoperatively
Relieved
Full return
Normal
Simple onset (yawning)
Relieved
Minimal residual weakness
Normal
Relieved
Minimal residual weakness
Normal
Relieved
Minimal triceps weakness only
Normal
Relieved
Full recovery
Normal
Rapid relief
Greatly improved
Normal
Very lateral disc rupture, disc adherent to C8 dural sheath C8 compression by adherent scarred, ruptured disc (decompression only) C8 compression by soft ruptured disc
Sensation
Comments
Very lateral disc, pure C8 lesion producing weakness in intrinsic muscles Very lateral disc, pure C8 lesion producing weakness in intrinsic muscles
~Operation: cervicalforaminotomy(C7-T1 level)•
vertebra, and subclavian arteriography may show stenosis or occlusion of the artery on abduction and external rotation of the arm. The associated involvement of the first thoracic nerve will also help in making this diagnosis.
finger. The distribution of the sensory loss is within the distribution of the seventh cervical nerve, with maximal involvement usually noted in the index finger and with extension along the lateral aspect of the forearm.
Pancoast's Tumor
First Thoracic Nerve Lesion
If there is a history of a previous neoplasm of the lung, a Pancoast's tumor may be suspected. Involvement of the eighth cervical nerve in this condition is usually accompanied by involvement of the first thoracic nerve and Homer's syndrome. Apical chest x-ray films and studies of the first rib may show evidence of neoplasia.
There is usually no clinical involvement of the triceps, extensor digitorum longus, or the flexor digitorum profundus muscles in cases of first thoracic nerve lesions. The sensory loss is in the distribution of the first thoracic nerve along the medial aspect of the upper arm from the elbow to the axilla, but the intrinsic muscle involvement can be identical. There may be an accompanying Homer's syndrome.
Myocardial Infarction When rupture of a disc involves the left eighth cervical nerve, as may also occur with a left seventh cervical nerve lesion, pain in the neck associated with pain in the arm and upper chest may lead to a mistaken diagnosis of myocardial infarction. Patient 1 was admitted to a coronary intensive care unit because of these symptoms, and Patient 7 was admitted to a medica ! ward with this diagnosis.
Seventh Cervical Nerve Lesion With involvement of the seventh cervical nerve there is lao involvement of the intrinsic muscles of the hand; the triceps involvement tends to be more pronounced and the triceps jerk more affected. The finger extensors are more diffusely involved, with maximal involvement of the index
Discussion Modem anatomical texts have contained such statements as: "Clinical observations indicate that all the small muscles of the hand receive their motor innervation from TI" [1]. It is clear from this study that the motor supply of the intrinsic hand muscles is not exclusively innervated by the first thoracic nerve. In Patients 4 and 5, the prolapse of the disc contacted the eighth cervical nerve quite lateral to the main cervical theca and did not simultaneously compress the first thoracic nerve. Both patients had obvious intrinsic weakness, and Patient 5 had muscle wasting as well. Eighth cervical nerve lesions may be mistaken for ulnar nerve lesions, lesions of the seventh cervical or first thoracic nerves, or myocardial infarction. Accurate diag-
Wallace: Compression of Eighth Cervical Nerve Root
nosis is essential if correct treatment is to be undertaken, and particularly if surgery is indicated. Lesions of the eighth cervical nerve may lead to clawing of the hand that superficially resembles ulnar clawing. I presume it occurs because of differential and graded innervation of the flexor digitorum profundus and extensor digitorum longus muscles to the fingers, with maximal innervation of the eighth cervical nerve to the fifth finger and minimal innervation to the: first finger. The cases of Patients 4 and 5 illustrate that nerve root compression can occur quite laterally, and in Patient 5 the myelogram was normal, though the cerebrospinal fluid protein level was high. ~ l a e n there is a strong clinical impression of a pure eighth cervical nerve lesion, the symptoms are severe and prolonged, and the myelogram is negative, consideration should be given to an exploratory operation. Patient 5, a general practitioner, suffered severe pain and underwent several years of psychiatric treatment for his pain and associated depression, which were engendered by prolapse of his disc. Surgical relief was further delayed by his negative myelogram, and during this delay he
299
developed renal disease due to the psychotropic drugs he was taking. Because of the limited amount of movement that occurs at the disc space between the seventh cervical and first thoracic vertebrae, neck movement may be normal in range and free of pain. In view of the findings in this series, it would appear that lesions of the eighth cervical nerve are probably not very rare, but are poorly recognized by practitioners, within and without the neurosurgical profession. My thanks to Mr. David Brownbill for referring Patient 4, and to Mrs. Maureen Kerriganfor typing the manuscript. References 1. Johnston TB, Davies DV, Davies F (eds): Gray's Anatomy, ed 32. London: Longmans, Green, 1958, p 652 2. LunsfordLD, Bissonette DJ, Jannetta PJ, Sheptak PE, Zomb DS: Anterior surgeryfor cervicaldisc disease. Part 1: Treatment of lateral cervical disc herniation in 253 cases. J Neurosurgery53:1-11, 1980 3. Northfield D: The Surgery of the Central Nervous System. Oxford: Blackwell, 1973, p 734
Book Review Tissue Fluid Pressure and Composition Edited by Alan R. Hargens Baltimore, Williams & Wilkins, 1981 275 pp., $34.00
Reviewed by Michael J. Rosner, M.D., Richmond, Virginia Dr. Hargens has edited a volume which constitutes a micro course in the study techniques, controversies, and applications of tissue fluid pressure measurements. The volume begins with introductory chapters dealing with what, to the uninitiated reader, appears to be a simple problem: to evaluate and measure tissue pressure. He quickly reveals the difficulty of the task. The major opposing theoretical orientations are discussed. Throughout, the prose is clear and concise. From the point of view of the neuroscientist interested in tissue pressures in the central and peripheral nervous systems, this volume is modera~:ely deficient. However, it certainly functions well as a basic introduction to the different techniques of tissue pressure measurement and the controversies inherent in each technique.
There are several chapters dealing with muscle and connective tissue. Two early chapters (9 and 10) deal with reasonably basic mechanisms of edema prevention/ formation and lymph flow, and they are nicely balanced by three clinically related chapters (21, 22, and 26). Pulmonary physiology and tissue pressure are well covered by three chapters. Three chapters (15, 17, and 18) are devoted to the obviously important topic of fluid and lymph flow in the bowel and mesentery. Tissue Fluid Pressure and Composition serves as a readable and concise introduction to the problem. The basic theoretical mathematics, chemistry, physical chemistry, and hydrodynamics are clearly reviewed and placed in the context of the difficulty of measurement and its attendant experimental controversies. Subsequent chapters introduce tissue pressure measurement as it relates to several organ systems in both normal and pathological states. Ultimately, the reader may be disappointed by the lack of a final and clear resolution to the many controversies introduced, but that is the price of a "state of the art" text.