- Email: [email protected]
Thoracic disc herniation
356
Surg Neurol 1985;23:356-61
Thoracic Disc Herniation Improved Diagnosis with Computed Tomographic Scanning and a Review of the Literature Carlos A. Arce, M.D., and George J. Dohrmann, M.D., Ph.D. Section of Neurosurgery, University of Chicago Medical Center, Chicago, Illinois
Arce CA, Dohrmann GJ. Thoracic disc herniation. Improved diagnosis with computed tomographic scanning and a review of the literature. Surg Neurol 1985;23:356-6.
A series of 280 patients with thoracic discs has been analyzed.
Thoracic disc herniation is uncommon. One of the main problems in the treatment of thoracic disc herniation has been the lack of accuracy of diagnostic tests. Now, with the use of computed tomographic scanning with and without metrizamide in the subarachnoid space, this accuracy has greatly improved, Computed tomography scanning can demonstrate the type and level of the lesion even when the myelographic study is negative. We have reviewed 280 cases; a peak incidence was noted in the fourth decade with 75% of the protruded discs occurring below T-8. Back pain was the most common presenting symptom followed by sensory disturbances. By the time of diagnosis, 70% of the patients had signs of spinal cord compression. A small group of patients could be identified that invariably had a good prognosis. They had a history of trauma, symptoms lasting less than a month, and soft disc herniation. Regarding the results of surgical treatment, there was a success rate ranging from 57% for decompressive laminectomy to over 80% for the posterolateral, lateral, and transthoracic approaches.
Illustrative Case
KEYWORDS: Thoracic disc herniation; Computed tomography of spine; Metrizamide myelography; Spinal cord compression
Thoracic disc herniation is uncommon. O f all herniated discs, less than 1% occur in the thoracic region. Myelography has been the diagnostic modality o f choice, but 8 % false negative results [6], and a correct preoperative diagnosis o f only 56% have been reported [18]. We have used computed tomographic scanning of the thoracic spine with and without metrizamide to more accurately demonstrate the type and level of the lesion.
Address reprint requests to: Dr. George J, Dohrmann, Section of Neurosurgery, University of Chicago Medical Center, 584l South Maryland Avenue, Chicago, Illinois 60637.
© 1985 by Elsevier Science Publishing Co., Inc.
A 53-year-old woman was in excellent health until 2 weeks prior to admission when she slipped on ice and fell on her right hip. She noticed on the same day some numbness in her right foot. Four days later she noticed a decreased temperature and pain perception in her right leg. These symptoms remained unchanged over the course of 1 week. On admission the general physical examination was normal. On neurological examination there was a T-6 sensory level with decreased pinprick and temperature sensibility on the right side. There was also a mild hyperreflexia involving the left lower extremity. The patient underwent a metrizamide myelogram that did not show any abnormalities (Figure 1). A computed tomographic scan showed a thoracic disc herniation at the T6-7 level (Figure 2). The disk was herniated posterolaterally on the left, compressing the dura mater, subarachnoid space, and anterolateral spinal cord. After the radiological studies, examination of the patient showed a loss o f the anal sphincter tone. The patient was taken to the operating room immediately and a left costotransversectomy with resection of the herniated T6-7 disc was performed. Postoperatively, she regained the anal sphincter tone and her sensory level dropped to T-10. Six months later she was asymptomatic with only mild hypalgesia from T-10 on the right side. Results and Comment Key, in 1838, was the first to describe spinal cord injury from a ruptured disc [8]. In 1911, Middleton and Teachers [4] described the postmortem finding o f a large herniated T-12 disc in a man with traumatic paraplegia. In 1931, Antoni [4] described what is probably the first case where the diagnosis of thoracic disc herniation was made antemortem. The same year Elsberg [ 10] reported 0090-3019/85/$3.30
Herniation of Thoracic Discs
Surg Neurol 1985;23:356-61
357
A
Figure t. Anteroposterior (A) and lateral (B) projections of metrizamide myelogram of the thoracic spine showing no abnormalities. (Compare with Figure 2.J
the first two patients treated surgically, although Adson was probably the first to have operated on a patient [ 18]. The patient operated upon by Adson in 1922 was given a diagnosis of"fibrochondroosteoma"; this was later found to be a degenerated thoracic disc. In 1934, Mixter and Barr [22] published four cases of protruded thoracic intervertebral disc. Two years later Hawk [13] pub-
lished an additional four cases, establishing the presence of the entity of thoracic disc herniation. Based on our review of 280 cases reported in the literature, 0 . 2 5 % - 0 . 7 5 % of protruded discs are in the thoracic region. About 80% of them presented between the third and fifth decades of life with a peak in the fourth decade (33%); the youngest patient was 12 years old and the oldest was 73. (Figure 3) A male-to-female ratio of 1.5 was noted (Table 1). Regarding the level of disc protrusion, 75% of the protruded thoracic intervertebral discs occurred below T-8 with a peak at the
358
Surg Neurol 1985;23:356-61
Arce and Dohrmann
Table 1. Ratio of Males to Females No. of cases %
Males
Females
138 60
91 40
The onset and duration o f symptoms are important in trying to define the natural history of protruded thoracic intevertebral discs. As can be seen in Table 3, the onset and duration of symptoms varied from hours to several years (histories as long as 26 years have been reported [3,18]. The presentation of protruded intervertebral discs can be divided into two groups of patients:
Figure 2. Computed tomographic scan with metrizamide in the subarachnoid space showing the herniated thoracic disc (arrow) compressing the anterolateral surface of the spinal cord (c). (Note." same patient as Figure 1.)
1. One group in which there was a history of symptoms of less than 1 month, more than 24 hours, and almost always associated with trauma and presenting with signs o f spinal cord compression or radicular symptoms. In most of these patients, a soft disc was found
Figure 4. Lerel of thoracic disc protrusion in 258 cases. T11-12 level of 2 6 % (Figure 4). Multiple protrusions o f thoracic discs have been reported [ 1,4,31,35] without any level of preference. The most common location o f the protrusion was central/centrolateral with almost 70% o f the protruded discs being in this location (Table 2). Much has been said about etiological factors in herniated thoracic intervertebral discs. Trauma has been considered an important factor by some [1,8,34] and unimportant by others [11,17]. A history o f trauma could be found in about 2 5 % of the cases reviewed. Degeneration of the disk seems to be the most important factor and the cause o f this remains uncertain.
%
rues 8 2 2 5
3 1 1 2
9
3
19 ~20
7 8
23
9
Figure 3. Distribution of 238 cases of thoracic disc herniation according
37
14
to age.
43
17
66
26
100 90,
~24 I
SO,
33%
70,
~ 6
50'
"23%,,
22%
20, I0,
I
0
10-19
20 - 29 30 - 39
40 - 49 AGE
50 - 59 60 - 69 70 - 79
9
75%
Herniation of Thoracic Discs
Surg Neurol 1985;23:356-61
359
Table 4. Initial Symptoms
Table 2. Location of Disc~ Type of disc
Central/ centrolateral
Lateral
No. of cases %
120 67
58 33
and a good recovery was obtained, regardless of the surgical approach used. 2. The second group includes the larger number of patients (over 90%) who presented with a longer history varying from months to several years in which a degenerative process of the disc seemed to be the main causative factor and in which a history of trauma could be found in about 20% o f the patients. Many patients in this group presented with signs o f spinal cord compression. The presence o f a soft or hard disc was variable. It is in this group o f patients where the operative approach seems to have played an important role in the final outcome. An exception was the small group o f patients with only radicular symptoms who invariably had excellent results regardless of operative approach.
Initial symptom
No. of patients
e/¢
Pain Sensory Motor Bladder
98 4(1 30 4
57 2 18 2
We could postulate, based on these facts, that the protruded disc and the constant pressure on the spinal cord produces progressive damage to the spinal cord, probably worsened by minor traumas or movement. The most common presenting symptom was pain (60% of the cases), followed by sensory disturbances. Bladder involvement, as the initial presenting symptom, was present in only 2 % of the patients (Table 4). The most common type of pain was midline back pain, followed by a radicular-type pain; low back pain was a common presenting symptom with protruded discs in the T-12 area. The most common sensory disturbance was numbness but other sensory modalities can also be affected. Paresthesia and/or dysesthesia have been described associated with protruded thoracic discs [8]. By the time of diagnosis, 70% of the patients had symptoms of spinal cord compression with motor and sensory disturbances of different degrees or a Brown-Sequard syndrome (Table 5). Sensory symptoms alone were present in 15% of patients and motor symptoms alone in 6 % of patients.
Radicular pain as the only complaint was present in only 9%. Bladder or sphincter disturbances were present in 31% o f patients at the time o f presentation. O f all tests for the diagnosis of protruded thoracic intervertebral discs, myelography was considered the test of choice. Excellent reviews o f the findings of myelography have been done [6,33]. In the series of Love and Schorn [18], 50 cases were studied with myelography and a correct preoperative diagnosis was made in only 56% of the cases; in the series of Baker et al [6] of 36 cases studied with myelography, three cases (8%) failed to show any abnormalities. However, with the advent o f computed tomographic scanning, a new era of diagnosis has started. We have used computed tomographic scanning o f the thoracic spine with and without metrizamide in the subarachnoid space to more accurately demonstrate the level and type of disc herniation. A negative metrizamide myelogram is shown in Figure 1 ; however, the computed tomographic scan in the same patient revealed the thoracic disc herniation clearly (Figure 2). Intradural penetration of a disc fragment, simulating an intradural tumor, has been reported [ 12,18,24]. The risk that such a fragment could be overlooked emphasizes the importance of an exact preoperative diagnosis. Computed tomographic scanning can demonstrate if there is any intradural component of the disc facilitating the treatment of these cases in this way. The treatment of herniated thoracic disks has evolved over the years. In the inital reports almost all of the patients were made worse. In the 1950s and 1960s a number of reports were made with somewhat better results but still a high rate of failure [1,4,5,11,12, 15,16,18,19,21,25,28,34]. The standard treatment consisted of a decompressive laminectomy with intradural
Table 3. Onset and Duration of Symptoms
Table 5. Symptoms at Diagnosis
Duration of symptoms
5
month months year years years years
No. of cases
Presenting symptoms
No. of patients
%
16 41 29 28 29 32
Motor and sensory Brown-Sequard syndrome Sensory symptoms only Motor symptoms only Radicular pain only Bladder or sphincter
127 18 ~l l3 19 64
6l 9 15 6 9 31
360
Surg N e u r o l 1985;23:356-61
Arce and D o h r m a n n
T a b l e 6. Review of Cases Approach/results
Total
Laminectomy Posterolateral approach Lateral approach Transthoracic
129 27 43 12
Asymptomatic
19 10 15 8
(15%) (37%) (35%) (67%)
and/or extradural removal of the disc. Of 119 cases [1,3,7,10-13,15,16,19,22,23,25,28,30-32,34,35] reviewed that were treated in this fashion, 28% were made worse with 11% remaining unchanged (Table 6). It is interesting to note the study by Singounas and Korvounis [30] in which they reported on eight patients treated with only decompressive laminectomy without attempt of removal of the disc. They noted good results in all of them; this is the only report of its type. In 1971, Carson et al [8] described a posterolateral approach; through a "T" type incision, a laminectomy with removal of the facet was done. In 1978, Patterson and Arbit [24] reported a similar approach, removing the facet and pedicle of the vertebral body inferior to the disc, followed by laminectomy. Of the 27 cases [8,24,29,32] that we have collected, treated with posterolateral approaches, 82% were improved or made asymptomatic, 11% remained unchanged, and 7% were made worse. In 1960, Hulme [ 14] was the first to use the lateral approach for a herniated thoracic disc. This approach is an extension of the costotransversectomy introduced by Menard in 1900 and developed by Capener in 1954 for treatment of Pott's disease. Hulme and others [2,7,9,20,33] have used this approach successfully. Of 43 cases that we have collected from the literature, 88% were improved or made asymptomatic and 12% remained unchanged; no patient was made worse. In 1958, Crafford reported the first right-sided transthoracic approach for removal of a herniated disc. In 1969, Perot and Munro [26] and Ransohoff et al [27] almost simultaneously published reports using a right or left transthoracic approach, respectively, with marked success. Of 12 such cases we have collected from the literature [2,26,27], all of them were treated successfully. As can be seen in Table 6, a marked improvement in the treatment and prognosis in patients with thoracic disc herniation has been accomplished, using the latter three types of operative procedures described above (over 80% success rate) compared with laminectomy. Because of the high percentage of patients made worse when operated upon via laminectomy compared with posterolateral, lateral, and anterior approaches, we believe that removal of a herniated thoracic disc through a laminectomy should be abandoned. With the improvement in surgical techniques and improved diagnosis using computed tomographic scanning,
Improved
55 12 23 4
(42%) (45%) (53%) (33%)
Unchanged
Worse
Died
14 ( l 1%) 3 (l 1%) 5 (12%) --
36 (28%) 2 (7%) ---
5 (4%~ ----
patients with thoracic disc herniation should be diagnosed earlier and should have improved operative results. References 1. Abbott KH, Reter RH. Protrusions of thoracic intervertebral disks. Neurology (NY)1956;6:1-10. 2. Albrand OW, Corkill G. Thoracic disk herniation: treatment and prognosis. Spine 1979;4:41-6. 3. Arseni C, Maresius M. Thoracic disc hernia (clinical-therapeutic considerations on 42 operated cases). Neurol Psychiatr Neurochir 1970;15:331-8. 4. Arseni C, Nash F. Thoracic intervertebral disk protrusion. A clinical study. J Neurosurg 1960; 17:418-30. 5. Arseni C, Nash F. Protrusion of thoracic intervertebral discs. Acta Neurochir 1963;11:1-33. 6. Baker HL, Love JG, Uihlein A. Roentgenologic features of protruded thoracic and intervertebral discs. Radiology 1965;84:1059-65. 7. Benson MKD, Byrnes DP. The clinical syndromes and surgical treatment of thoracic intervertebral disc proplapse. J Bone Joint Surg (Br) 1957;4:471-7 8. Carson J, Gumpert J, Jefferson A, Diagnosis and treatment of thoracic intervertebral disc protrusions. J Neurol Neurosurg Psychiatry 197 l ;34:68-77. 9. Chesterman PJ, Bonney GL. Spastic paraplegia caused by sequestrated thoracic intervertebral disc. Proc R Soc Med 1964;57:87-8. 10. Elsberg CA. The extradural ventral chondromas (ecchondroses), their favorite sites, the spinal cord and root symptoms they produce, and their surgical treatment. Bull Neurol Inst New York 1931;1:350-88. 11. Epstein JA. The syndrome of herniation of lower thoracic intervertebral discs with nerve root and spinal cord compression. A presentation of 4 cases with review of the literature, methods of diagnosis and treatment. J Neurosurg 1954;l 1:525-38. 12. Fisher RG. Protrusion of thoracic disc: the factor of herniation through the dura mater. J Neurosurg 1965;22:591-3. 13. Hawk WA. Spinal compression caused by ecchondrosis of the intervertebral fibrocartilage: with a review of the recent literature. Brain 1936;58:204-24. 14. Hulme A. The surgical approach to thoracic intervertebral disc protrusions. J Neurol Neurosurg Psychiatry 1960;23;133-7. 15. Kite WC Jr, Whitfield RH, Campbell E. The thoracic herniated intervertebral disc syndrome. J Neurosurg 1957;14:61-7. 16. Logue V. Thoracic intervertebral disc prolapse with spinal cord compression. J Neurol Neurosurg Psychiatry 1952;15:227-41. 17. Love JG, Kiefer EJ. Root pain and paraplegia due to protrusions of thoracic intervertebral disks. J Neurosurg 1950;7:62-9. 18. Love JG, Schorn VG. Thoracic-disc protrusions. JAMA 1965;191:627-31. 19. MacCartee CC, Griffin DD, Byrd EB. Ruptured calcified thoracic disc in a child. J Bone Joint Surg 1972;54:1272-4. 20. Maiman DJ, Larson SJ, Luck E, EI-Ghatit A. Lateral extracavitary
Herniation of Thoracic Discs
21. 22. 23. 24. 25.
26.
27.
approach to the spine for thoracic disc herniation: report of 23 cases. Neurosurgery 1984;14:178-82. Malukiewicz W. Thoracic intervertebral disc protrusions. Neurol Neurochir Pol 1973;7:863-5. Mixter WJ, Barr JS. Rupture of the intervertebral disc with involvement of the spinal canal. New Engl J Med 1934;211:210-5. Muller R. Protrusion of thoracic intervertebral disks with compression of the spinal cord. Acta Med Scand 1951 ;139:99-104. Patterson RH, Arbit E. A surgical approach through the pedicle to protruded thoracic discs. J Neurosurg 1978;48:768-72. Peck FCJr. A calcified thoracic intervertebral disk with herniation and spinal cord compression in a child. Case report. J Neurosurg 1957;14:105-9. Perot PL Jr, Munro DD. Transthoracic removal of midline thoracic disc protrusions causing spinal cord compression. J Neurosurg 1969;31:452-8. RansohoffJ, Spencer F, Siew F, Gage L Jr. Transthoracic removal of thoracic disc. Report of three cases. J Neurosurg 1969;31:459-61.
Surg N e u r o l 1985;23:356-61
361
28. Reeves DL, Brown HA. Thoracic intervertebral disc protrusion with spinal cord compression. J Neurosurg 1968;28:24-8. 29. Signorini G, Baldini M, Vivenzo C, Princi L, Tonnarelli GP. Surgical treatment of thoracic disc protrusion. Acta Neurochir (Wien) 1979;49:245-54. 30. Singounas EG, Karvounis PC. Thoracic disc protrusion. Acta Neurochir (Wien) 1977;39;251-8. 31. Svien H J, Karavitis AL, Multiple protrusions of intervertebral disks in the upper thoracic region: report of a case. Proc Staff Meet Mayo Clin 1954;29:375-8. 32. Terry AF, McSweeney T, Jones HWF. Paraplegia as a sequela to dorsal disc prolapse. Paraplegia 198 [ ; 19: l 11-7. 33. Thomson JLG. Myelography in dorsal disc protrusion. Acta Radiol (Diagn)(Stockh) 1966;5:1140-6. 34. Tovi D, Straug RR. Thoracic intervertebral disc protrusions. Acta Chir Scand Suppl 1960;267:1-41. 35. Van Landingham JH. Herniation of thoracic intervertebral discs with spinal cord compression in kyphosis dorsalis juvenilis (Scheurmann's disease). Case report. J Neurosurg 1954;11:327-9.
Surg Neurol 1985;23:356-61
Thoracic Disc Herniation Improved Diagnosis with Computed Tomographic Scanning and a Review of the Literature Carlos A. Arce, M.D., and George J. Dohrmann, M.D., Ph.D. Section of Neurosurgery, University of Chicago Medical Center, Chicago, Illinois
Arce CA, Dohrmann GJ. Thoracic disc herniation. Improved diagnosis with computed tomographic scanning and a review of the literature. Surg Neurol 1985;23:356-6.
A series of 280 patients with thoracic discs has been analyzed.
Thoracic disc herniation is uncommon. One of the main problems in the treatment of thoracic disc herniation has been the lack of accuracy of diagnostic tests. Now, with the use of computed tomographic scanning with and without metrizamide in the subarachnoid space, this accuracy has greatly improved, Computed tomography scanning can demonstrate the type and level of the lesion even when the myelographic study is negative. We have reviewed 280 cases; a peak incidence was noted in the fourth decade with 75% of the protruded discs occurring below T-8. Back pain was the most common presenting symptom followed by sensory disturbances. By the time of diagnosis, 70% of the patients had signs of spinal cord compression. A small group of patients could be identified that invariably had a good prognosis. They had a history of trauma, symptoms lasting less than a month, and soft disc herniation. Regarding the results of surgical treatment, there was a success rate ranging from 57% for decompressive laminectomy to over 80% for the posterolateral, lateral, and transthoracic approaches.
Illustrative Case
KEYWORDS: Thoracic disc herniation; Computed tomography of spine; Metrizamide myelography; Spinal cord compression
Thoracic disc herniation is uncommon. O f all herniated discs, less than 1% occur in the thoracic region. Myelography has been the diagnostic modality o f choice, but 8 % false negative results [6], and a correct preoperative diagnosis o f only 56% have been reported [18]. We have used computed tomographic scanning of the thoracic spine with and without metrizamide to more accurately demonstrate the type and level of the lesion.
Address reprint requests to: Dr. George J, Dohrmann, Section of Neurosurgery, University of Chicago Medical Center, 584l South Maryland Avenue, Chicago, Illinois 60637.
© 1985 by Elsevier Science Publishing Co., Inc.
A 53-year-old woman was in excellent health until 2 weeks prior to admission when she slipped on ice and fell on her right hip. She noticed on the same day some numbness in her right foot. Four days later she noticed a decreased temperature and pain perception in her right leg. These symptoms remained unchanged over the course of 1 week. On admission the general physical examination was normal. On neurological examination there was a T-6 sensory level with decreased pinprick and temperature sensibility on the right side. There was also a mild hyperreflexia involving the left lower extremity. The patient underwent a metrizamide myelogram that did not show any abnormalities (Figure 1). A computed tomographic scan showed a thoracic disc herniation at the T6-7 level (Figure 2). The disk was herniated posterolaterally on the left, compressing the dura mater, subarachnoid space, and anterolateral spinal cord. After the radiological studies, examination of the patient showed a loss o f the anal sphincter tone. The patient was taken to the operating room immediately and a left costotransversectomy with resection of the herniated T6-7 disc was performed. Postoperatively, she regained the anal sphincter tone and her sensory level dropped to T-10. Six months later she was asymptomatic with only mild hypalgesia from T-10 on the right side. Results and Comment Key, in 1838, was the first to describe spinal cord injury from a ruptured disc [8]. In 1911, Middleton and Teachers [4] described the postmortem finding o f a large herniated T-12 disc in a man with traumatic paraplegia. In 1931, Antoni [4] described what is probably the first case where the diagnosis of thoracic disc herniation was made antemortem. The same year Elsberg [ 10] reported 0090-3019/85/$3.30
Herniation of Thoracic Discs
Surg Neurol 1985;23:356-61
357
A
Figure t. Anteroposterior (A) and lateral (B) projections of metrizamide myelogram of the thoracic spine showing no abnormalities. (Compare with Figure 2.J
the first two patients treated surgically, although Adson was probably the first to have operated on a patient [ 18]. The patient operated upon by Adson in 1922 was given a diagnosis of"fibrochondroosteoma"; this was later found to be a degenerated thoracic disc. In 1934, Mixter and Barr [22] published four cases of protruded thoracic intervertebral disc. Two years later Hawk [13] pub-
lished an additional four cases, establishing the presence of the entity of thoracic disc herniation. Based on our review of 280 cases reported in the literature, 0 . 2 5 % - 0 . 7 5 % of protruded discs are in the thoracic region. About 80% of them presented between the third and fifth decades of life with a peak in the fourth decade (33%); the youngest patient was 12 years old and the oldest was 73. (Figure 3) A male-to-female ratio of 1.5 was noted (Table 1). Regarding the level of disc protrusion, 75% of the protruded thoracic intervertebral discs occurred below T-8 with a peak at the
358
Surg Neurol 1985;23:356-61
Arce and Dohrmann
Table 1. Ratio of Males to Females No. of cases %
Males
Females
138 60
91 40
The onset and duration o f symptoms are important in trying to define the natural history of protruded thoracic intevertebral discs. As can be seen in Table 3, the onset and duration of symptoms varied from hours to several years (histories as long as 26 years have been reported [3,18]. The presentation of protruded intervertebral discs can be divided into two groups of patients:
Figure 2. Computed tomographic scan with metrizamide in the subarachnoid space showing the herniated thoracic disc (arrow) compressing the anterolateral surface of the spinal cord (c). (Note." same patient as Figure 1.)
1. One group in which there was a history of symptoms of less than 1 month, more than 24 hours, and almost always associated with trauma and presenting with signs o f spinal cord compression or radicular symptoms. In most of these patients, a soft disc was found
Figure 4. Lerel of thoracic disc protrusion in 258 cases. T11-12 level of 2 6 % (Figure 4). Multiple protrusions o f thoracic discs have been reported [ 1,4,31,35] without any level of preference. The most common location o f the protrusion was central/centrolateral with almost 70% o f the protruded discs being in this location (Table 2). Much has been said about etiological factors in herniated thoracic intervertebral discs. Trauma has been considered an important factor by some [1,8,34] and unimportant by others [11,17]. A history o f trauma could be found in about 2 5 % of the cases reviewed. Degeneration of the disk seems to be the most important factor and the cause o f this remains uncertain.
%
rues 8 2 2 5
3 1 1 2
9
3
19 ~20
7 8
23
9
Figure 3. Distribution of 238 cases of thoracic disc herniation according
37
14
to age.
43
17
66
26
100 90,
~24 I
SO,
33%
70,
~ 6
50'
"23%,,
22%
20, I0,
I
0
10-19
20 - 29 30 - 39
40 - 49 AGE
50 - 59 60 - 69 70 - 79
9
75%
Herniation of Thoracic Discs
Surg Neurol 1985;23:356-61
359
Table 4. Initial Symptoms
Table 2. Location of Disc~ Type of disc
Central/ centrolateral
Lateral
No. of cases %
120 67
58 33
and a good recovery was obtained, regardless of the surgical approach used. 2. The second group includes the larger number of patients (over 90%) who presented with a longer history varying from months to several years in which a degenerative process of the disc seemed to be the main causative factor and in which a history of trauma could be found in about 20% o f the patients. Many patients in this group presented with signs o f spinal cord compression. The presence o f a soft or hard disc was variable. It is in this group o f patients where the operative approach seems to have played an important role in the final outcome. An exception was the small group o f patients with only radicular symptoms who invariably had excellent results regardless of operative approach.
Initial symptom
No. of patients
e/¢
Pain Sensory Motor Bladder
98 4(1 30 4
57 2 18 2
We could postulate, based on these facts, that the protruded disc and the constant pressure on the spinal cord produces progressive damage to the spinal cord, probably worsened by minor traumas or movement. The most common presenting symptom was pain (60% of the cases), followed by sensory disturbances. Bladder involvement, as the initial presenting symptom, was present in only 2 % of the patients (Table 4). The most common type of pain was midline back pain, followed by a radicular-type pain; low back pain was a common presenting symptom with protruded discs in the T-12 area. The most common sensory disturbance was numbness but other sensory modalities can also be affected. Paresthesia and/or dysesthesia have been described associated with protruded thoracic discs [8]. By the time of diagnosis, 70% of the patients had symptoms of spinal cord compression with motor and sensory disturbances of different degrees or a Brown-Sequard syndrome (Table 5). Sensory symptoms alone were present in 15% of patients and motor symptoms alone in 6 % of patients.
Radicular pain as the only complaint was present in only 9%. Bladder or sphincter disturbances were present in 31% o f patients at the time o f presentation. O f all tests for the diagnosis of protruded thoracic intervertebral discs, myelography was considered the test of choice. Excellent reviews o f the findings of myelography have been done [6,33]. In the series of Love and Schorn [18], 50 cases were studied with myelography and a correct preoperative diagnosis was made in only 56% of the cases; in the series of Baker et al [6] of 36 cases studied with myelography, three cases (8%) failed to show any abnormalities. However, with the advent o f computed tomographic scanning, a new era of diagnosis has started. We have used computed tomographic scanning o f the thoracic spine with and without metrizamide in the subarachnoid space to more accurately demonstrate the level and type of disc herniation. A negative metrizamide myelogram is shown in Figure 1 ; however, the computed tomographic scan in the same patient revealed the thoracic disc herniation clearly (Figure 2). Intradural penetration of a disc fragment, simulating an intradural tumor, has been reported [ 12,18,24]. The risk that such a fragment could be overlooked emphasizes the importance of an exact preoperative diagnosis. Computed tomographic scanning can demonstrate if there is any intradural component of the disc facilitating the treatment of these cases in this way. The treatment of herniated thoracic disks has evolved over the years. In the inital reports almost all of the patients were made worse. In the 1950s and 1960s a number of reports were made with somewhat better results but still a high rate of failure [1,4,5,11,12, 15,16,18,19,21,25,28,34]. The standard treatment consisted of a decompressive laminectomy with intradural
Table 3. Onset and Duration of Symptoms
Table 5. Symptoms at Diagnosis
Duration of symptoms
month months year years years years
No. of cases
Presenting symptoms
No. of patients
%
16 41 29 28 29 32
Motor and sensory Brown-Sequard syndrome Sensory symptoms only Motor symptoms only Radicular pain only Bladder or sphincter
127 18 ~l l3 19 64
6l 9 15 6 9 31
360
Surg N e u r o l 1985;23:356-61
Arce and D o h r m a n n
T a b l e 6. Review of Cases Approach/results
Total
Laminectomy Posterolateral approach Lateral approach Transthoracic
129 27 43 12
Asymptomatic
19 10 15 8
(15%) (37%) (35%) (67%)
and/or extradural removal of the disc. Of 119 cases [1,3,7,10-13,15,16,19,22,23,25,28,30-32,34,35] reviewed that were treated in this fashion, 28% were made worse with 11% remaining unchanged (Table 6). It is interesting to note the study by Singounas and Korvounis [30] in which they reported on eight patients treated with only decompressive laminectomy without attempt of removal of the disc. They noted good results in all of them; this is the only report of its type. In 1971, Carson et al [8] described a posterolateral approach; through a "T" type incision, a laminectomy with removal of the facet was done. In 1978, Patterson and Arbit [24] reported a similar approach, removing the facet and pedicle of the vertebral body inferior to the disc, followed by laminectomy. Of the 27 cases [8,24,29,32] that we have collected, treated with posterolateral approaches, 82% were improved or made asymptomatic, 11% remained unchanged, and 7% were made worse. In 1960, Hulme [ 14] was the first to use the lateral approach for a herniated thoracic disc. This approach is an extension of the costotransversectomy introduced by Menard in 1900 and developed by Capener in 1954 for treatment of Pott's disease. Hulme and others [2,7,9,20,33] have used this approach successfully. Of 43 cases that we have collected from the literature, 88% were improved or made asymptomatic and 12% remained unchanged; no patient was made worse. In 1958, Crafford reported the first right-sided transthoracic approach for removal of a herniated disc. In 1969, Perot and Munro [26] and Ransohoff et al [27] almost simultaneously published reports using a right or left transthoracic approach, respectively, with marked success. Of 12 such cases we have collected from the literature [2,26,27], all of them were treated successfully. As can be seen in Table 6, a marked improvement in the treatment and prognosis in patients with thoracic disc herniation has been accomplished, using the latter three types of operative procedures described above (over 80% success rate) compared with laminectomy. Because of the high percentage of patients made worse when operated upon via laminectomy compared with posterolateral, lateral, and anterior approaches, we believe that removal of a herniated thoracic disc through a laminectomy should be abandoned. With the improvement in surgical techniques and improved diagnosis using computed tomographic scanning,
Improved
55 12 23 4
(42%) (45%) (53%) (33%)
Unchanged
Worse
Died
14 ( l 1%) 3 (l 1%) 5 (12%) --
36 (28%) 2 (7%) ---
5 (4%~ ----
patients with thoracic disc herniation should be diagnosed earlier and should have improved operative results. References 1. Abbott KH, Reter RH. Protrusions of thoracic intervertebral disks. Neurology (NY)1956;6:1-10. 2. Albrand OW, Corkill G. Thoracic disk herniation: treatment and prognosis. Spine 1979;4:41-6. 3. Arseni C, Maresius M. Thoracic disc hernia (clinical-therapeutic considerations on 42 operated cases). Neurol Psychiatr Neurochir 1970;15:331-8. 4. Arseni C, Nash F. Thoracic intervertebral disk protrusion. A clinical study. J Neurosurg 1960; 17:418-30. 5. Arseni C, Nash F. Protrusion of thoracic intervertebral discs. Acta Neurochir 1963;11:1-33. 6. Baker HL, Love JG, Uihlein A. Roentgenologic features of protruded thoracic and intervertebral discs. Radiology 1965;84:1059-65. 7. Benson MKD, Byrnes DP. The clinical syndromes and surgical treatment of thoracic intervertebral disc proplapse. J Bone Joint Surg (Br) 1957;4:471-7 8. Carson J, Gumpert J, Jefferson A, Diagnosis and treatment of thoracic intervertebral disc protrusions. J Neurol Neurosurg Psychiatry 197 l ;34:68-77. 9. Chesterman PJ, Bonney GL. Spastic paraplegia caused by sequestrated thoracic intervertebral disc. Proc R Soc Med 1964;57:87-8. 10. Elsberg CA. The extradural ventral chondromas (ecchondroses), their favorite sites, the spinal cord and root symptoms they produce, and their surgical treatment. Bull Neurol Inst New York 1931;1:350-88. 11. Epstein JA. The syndrome of herniation of lower thoracic intervertebral discs with nerve root and spinal cord compression. A presentation of 4 cases with review of the literature, methods of diagnosis and treatment. J Neurosurg 1954;l 1:525-38. 12. Fisher RG. Protrusion of thoracic disc: the factor of herniation through the dura mater. J Neurosurg 1965;22:591-3. 13. Hawk WA. Spinal compression caused by ecchondrosis of the intervertebral fibrocartilage: with a review of the recent literature. Brain 1936;58:204-24. 14. Hulme A. The surgical approach to thoracic intervertebral disc protrusions. J Neurol Neurosurg Psychiatry 1960;23;133-7. 15. Kite WC Jr, Whitfield RH, Campbell E. The thoracic herniated intervertebral disc syndrome. J Neurosurg 1957;14:61-7. 16. Logue V. Thoracic intervertebral disc prolapse with spinal cord compression. J Neurol Neurosurg Psychiatry 1952;15:227-41. 17. Love JG, Kiefer EJ. Root pain and paraplegia due to protrusions of thoracic intervertebral disks. J Neurosurg 1950;7:62-9. 18. Love JG, Schorn VG. Thoracic-disc protrusions. JAMA 1965;191:627-31. 19. MacCartee CC, Griffin DD, Byrd EB. Ruptured calcified thoracic disc in a child. J Bone Joint Surg 1972;54:1272-4. 20. Maiman DJ, Larson SJ, Luck E, EI-Ghatit A. Lateral extracavitary
Herniation of Thoracic Discs
21. 22. 23. 24. 25.
26.
27.
approach to the spine for thoracic disc herniation: report of 23 cases. Neurosurgery 1984;14:178-82. Malukiewicz W. Thoracic intervertebral disc protrusions. Neurol Neurochir Pol 1973;7:863-5. Mixter WJ, Barr JS. Rupture of the intervertebral disc with involvement of the spinal canal. New Engl J Med 1934;211:210-5. Muller R. Protrusion of thoracic intervertebral disks with compression of the spinal cord. Acta Med Scand 1951 ;139:99-104. Patterson RH, Arbit E. A surgical approach through the pedicle to protruded thoracic discs. J Neurosurg 1978;48:768-72. Peck FCJr. A calcified thoracic intervertebral disk with herniation and spinal cord compression in a child. Case report. J Neurosurg 1957;14:105-9. Perot PL Jr, Munro DD. Transthoracic removal of midline thoracic disc protrusions causing spinal cord compression. J Neurosurg 1969;31:452-8. RansohoffJ, Spencer F, Siew F, Gage L Jr. Transthoracic removal of thoracic disc. Report of three cases. J Neurosurg 1969;31:459-61.
Surg N e u r o l 1985;23:356-61
361
28. Reeves DL, Brown HA. Thoracic intervertebral disc protrusion with spinal cord compression. J Neurosurg 1968;28:24-8. 29. Signorini G, Baldini M, Vivenzo C, Princi L, Tonnarelli GP. Surgical treatment of thoracic disc protrusion. Acta Neurochir (Wien) 1979;49:245-54. 30. Singounas EG, Karvounis PC. Thoracic disc protrusion. Acta Neurochir (Wien) 1977;39;251-8. 31. Svien H J, Karavitis AL, Multiple protrusions of intervertebral disks in the upper thoracic region: report of a case. Proc Staff Meet Mayo Clin 1954;29:375-8. 32. Terry AF, McSweeney T, Jones HWF. Paraplegia as a sequela to dorsal disc prolapse. Paraplegia 198 [ ; 19: l 11-7. 33. Thomson JLG. Myelography in dorsal disc protrusion. Acta Radiol (Diagn)(Stockh) 1966;5:1140-6. 34. Tovi D, Straug RR. Thoracic intervertebral disc protrusions. Acta Chir Scand Suppl 1960;267:1-41. 35. Van Landingham JH. Herniation of thoracic intervertebral discs with spinal cord compression in kyphosis dorsalis juvenilis (Scheurmann's disease). Case report. J Neurosurg 1954;11:327-9.