31 Principles of Microsurgical Discectomy in Lumbar Disc Herniations
H.M. Mayer
31.1
Terminology
The term “microsurgical discectomy” describes the re- moval of herniated parts of lumbar intervertebral discs through a posterior approach with the help of a surgi- cal microscope and microsurgical instruments. It im- plies the application of the general principles of micro- surgery as well as the approach to the anatomical target area through a limited skin incision.
31.2
Surgical Principle
For herniated lumbar discs which are medial, parame- dian (between midline and medial border of the pedi- cle), or intraforaminal (between medial and lateral bor- der of the pedicle), the pathology is approached through a paramedian incision (5 mm from the spinous process on the symptomatic side). The dorsolumbar fascia is incised and the muscles are bluntly retracted from medial to lateral without dissecting any of the in- sertions. Thus, the interlaminar region (window) is ap- proached. The yellow ligament is opened laterally and the nerve root is exposed and mobilized. The herniated part of the lumbar disc is removed and the rest of the nucleus pulposus can be removed from the interverte- bral space in order to decrease the rate of recurrent her- niations. The procedure is performed with the help of a surgical microscope using the microscope “from skin to skin” (see Chapter 3). In extraforaminal disc hernia- tions, the skin incision is between 3 and 5 cm lateral to the midline. The dorsolumbar fascia is opened in a semicircular manner and the intertransverse space is approached via blunt transmuscular dissection. The in- tertransverse ligament and muscle are excised lateral to the facet joint, and the dorsal root ganglion is exposed.
It is mobilized if necessary to expose the disc herniation which usually compresses the ganglion toward the low- er borders of the pedicle. The disc herniation is re- moved. In the majority of cases, no attempts are made to remove disc material from the intervertebral space.
The spinal canal is not opened (see Chapter 34).
31.3 History
The surgical treatment of lumbar disc herniations is characterized by several historical landmarks within the last 90 years. It was Oppenheim and Krause in 1909, Steinke in 1918, Adson in 1922, Stookey in 1922, and Dandy in 1929 who first described lumbar disc opera- tions which were in fact misdiagnosed as “spinal tu- mors” or “chondromas” [1, 11, 40, 50, 52]. In 1934 Mix- ter and Barr defined disc tissue as the morphological correlate for low back pain and sciatica in their pa- tients. Their historical paper about the treatment of
“ruptured lumbar discs” by laminectomy marks the beginning of “disc surgery” which dominates spine surgery of today at least by numbers [35]. With the de- velopment of myelography and discography, the diag- nosis and localization of lumbar disc herniations be- came easier in the following years [31]. The surgical approaches became less invasive so that hemilaminec- tomies were the standard surgical approach for the majority of disc herniations at the beginning of the 1970s.
Despite this progress, the clinical results of lumbar disc surgery remained moderate. In the majority of the patients the neurological symptoms as well as the ra- dicular pain could be improved, however, due to persis- tent or even worse low back pain, the clinical success rate varied between 4 % and 44 % in publications of the 1970s and beginning of the 1980s [4 – 6, 18, 19, 27, 37, 43, 49] (Table 31.1).
The rising numbers of patients with so-called failed- back-surgery syndromes was an indicator for the con- tribution of the surgical technique to postoperative complaints. Indeed, most of the postoperative prob- lems patients were facing were a result of traumatizing surgical approaches, lesions to nerve roots and bony structures, as well as wrong level explorations.
The application of microsurgical techniques to the
treatment of lumbar disc herniations is due to the ef-
forts of Yasargil, Williams, Wilson, Goald, and Caspar
[7, 15, 20 – 22, 54, 63 – 67, 69].
Table 31.1. Results of “stan- dard” non-microsurgical lumbar discectomy
Author Patients Results(%)
(n) Satisfied Not satisfied
Jochheim et al. (1961) [25] 188 84 16
Bushe et al. (1968) [6] 404 95 5
Biehl and Peters (1971) [5] 450 81.8 18.2
Oldenkott (1971) [37] 733 70 30
Biehl (1974) [4] 640 82.7 17.3
Vogt (1974) [56] 119 76.5 23.5
Salenius and Laurent (1977) [43] 886 56 44
Thomalske et al. (1977) [53] 1,000 93.2 6.8
Finneson (1978) [18] 296 67.6 32.4
Frenkel and Angehoefer (1978) [19] 124 96 4
Schramm et al. (1978) [47] 3,238 > 80
Berger (1979) [3] 1,101 87.7 12.3
Oldenkott (1979) [38] 760 89 11
Mayer and Reiche (1982) [32] 139 88 12
31.4 Advantages
The main advantages of microsurgical discectomy are No restrictions in indication
Magnification and illumination of the surgical field Reduced skin incision
Reduced damage to paravertebral muscles Reduced trauma to osseous structures
Improved hemostasis due to meticulous prepara- tion of epidural veins
Gentle preparation of neurological tissues Decreased blood loss
Less severe complications Homogenous clinical results Decreased operating room time Decreased postoperative morbidity Shorter hospitalization
Outpatient procedure
Positive didactic effects for the surgeon (preopera- tive planning) and for the assistant (can follow the operation)
31.5
Disadvantages
There are a few inherent disadvantages of microsurgery which also apply to lumbar disc operations:
Small field of vision with the danger of creating in- direct lesions to nerves of blood vessels
Training (learning by doing) necessary for sur- geons who are not educated in microsurgery
31.6 Indications
Microsurgery for the treatment of lumbar disc hernia- tions is indicated in all kinds and forms of herniation:
Medial, paramedian, intra- and extraforaminal herniations
Subligamentous, epidural extrusions with and without free fragments
Disc herniations of all kinds associated with lateral or central spinal stenosis
Disc herniations associated with non-symptomatic segmental instability
31.7
Contraindications
There are no contraindications for lumbar microdis- cectomy.
31.8
Surgical Technique, Postoperative Care, and Complications
See following chapters.
31.9 Results
The analysis of 11 retrospective clinical studies per-
formed between 1977 and 1993 (n = 3,543 patients) re-
veals clinical success rates of microdiscectomy between
76 % and 100 % with a postoperative follow-up time of
between 6 months and 5.5 years (Table 31.2). The major
differences between microsurgical and macrosurgical
Table 31.2. Clinical success rates of microdiscectomy (range, 76 – 100 %) with a postoperative follow-up time of between 6 months and 5.5 years
Author Patients Results(%)
(n) Satisfied Not satisfied
Yasargil (1977) [69] 100 100 0
Williams (1978) [63] 530 91 9
Goald (1978) [20] 147 96 4
Goald (1981) [22] 477 91 9
Ebeling and Reulen (1983) [14] 150 82 18
Hudgins (1983) [24] 157 91 9
Ebeling et al. (1986) [16] 485 91 9
Williams (1986) [64] 903 86 14
Ferrer et al. (1988) [17] 100 76 24
McCulloch (1989) [33] 257 84 16
Kotilainen et al. (1993) [29] 237 92 8
Table 31.3. Microsurgical (Mic) versus standard macrosurgical (Mac) technique
Author Patients Stay in hospital Unfit for work Follow-up Good outcome Reoperations
(days) (weeks) (years) (%) (%)
Wilson and Harbaugh (1981) [66] Mic 100 1 4.8 2 – 2
Mac 100 2.5 11.8 2 – 8
Kho and Steudel (1986) [28] Mic 131 – – 1 – 5 93 2.5
Mac 136 – – 1 – 5 93 0
Nyström (1987) [36] Mic 56 5 8 3 89 –
Mac 33 13.3 18.4 6.3 59 –
Mac 31 14.5 15.6 6.4 68 –
Silvers (1988) [48] Mic 270 3.7 10.6 – 98 5.1
Mac 270 7.1 13.4 – 95 5.5
Probst (1989) [41] Mic 150 – – 1.5 95 4
Mac 150 – – 1.5 90 3.3
Kahanovitz et al. (1989) [26] Mic 30 2 8 1.5 – –
Mac 34 7 7 1.5 – –
Andrews and Lavyne (1990) [2] Mic 112 2.8 5.5 – 9.9 1 97 4.5
Mac 30 9 12.4 3.5 88 11.4
Caspar et al. (1991) [9] Mic 299 – 16.4 – 93.5 5.7
Mac 199 – 18.6 – 83.3 12.6
techniques are that the overall success rates are higher and that the results are more homogenous in patients undergoing a microdiscectomy (Table 31.3).
31.10
Critical Evaluation
Microsurgical and endoscopic techniques have revo- lutionized a great number of surgical specialties. The development of imaging techniques as well as of tech- nical equipment has always had one common goal:
to achieve the technical goal of a surgical procedure with less tissue trauma in a fast and efficient way. This should always result in better or at least comparable clinical results. All surgical specialties which have adopted microsurgical techniques since the 1970s have had this benefit for a vast number of surgical interventions. Although there is a still ongoing dis- cussion about the benefit of microsurgical discec-
tomy, the arguments against this technique are fading away.
It has been proved that microsurgical discectomy does not prolong the operation time. Microsurgery does not lead to a significantly higher number of wrong level explorations or missed disc fragments. Microsur- gery can be used for all kinds of disc herniations with- out any anatomical, technical, or philosophical restric- tions. Microdiscectomy has brought an enormous ben- efit in the treatment of extraforaminal disc herniations (see Chapter 34). The overall rate of complications is not increased, and the rate of severe intraoperative complications is decreased as compared to standard techniques [61].
Many arguments against microsurgery are superfi-
cial and biased. There is no need for prospective ran-
domized studies to prove the benefits of the microsur-
gical philosophy as long as comparable clinical results
can be achieved with less tissue trauma.
Bibliography
1. Adson AW, Ott WO (1922) Results of the removal of tumors of the spinal cord. Arch Neurol Psychiatr (Chicago) 8:
520 – 538
2. Andrews DW, Lavyne MH (1990) Retrospective analysis of microsurgical and standard lumbar discectomy. Spine 15:
329 – 335
3. Berger A (1979) Operative Behandlung des lumbalen Bandscheibenvorfalles. – Ergebnisse der Operation 1 – 20 Jahre danach Inauguraldissertation, Univ. Tübingen 4. Biehl G (1974) Subjektive Ergebnisbeurteilung bei 640
Bandscheibenoperationen aufgrund einer Fragebogenak- tion. Z Orthop 112:825 – 827
5. Biehl G, Peters G (1971) Behandlungsergebnisse bei 450 Bandscheibenoperationen. Z Orthop 109:836 – 847 6. Bushe KA, Deftereos T, Schäfer E (1968) Lumbago und
Wurzelischialgie. Dtsch Med Wschr 93:1171 – 1176 7. Caspar W (1977) A new surgical procedure for lumbar disc
herniation causing less tissue damage through a microsur- gical approach. In: Wüllenweber R, Brock M, Hamer J, et al (eds) Advances in neurosurgery, vol 4. Springer, Berlin Heidelberg New York, pp 74 – 77
8. Caspar W (1986) Die mikrochirurgische OP-Technik des lumbalen Bandscheibenvorfalls. Empfehlungen zum Ope- rationsablauf. Aesculap, Tuttlingen
9. Caspar W, Campbell B, Barbier DD, Kretschmer R, Got- fried Y (1991) The Caspar microsurgical discectomy and comparison with a conventional standard lumbar disc procedure. Neurosurgery 28:78 – 87
10. Chafetz NI, Genant HK, Moon KL, Helms CA (1983) Rec- ognition of lumbar disc herniation with NMR. Am J Radiol 141:1153 – 1156
11. Dandy WE (1929) Loose cartilage from intervertebral disk simulating tumor of the spinal cord. Arch Surg (Chicago) 19:660 – 672
12. Dauch WA (1986) Infection of the intervertebral space fol- lowing conventional and microsurgical operations on the herniated lumbar intervertebral disc. A controlled clinical trial. Acta Neurochir (Wien) 82:43 – 49
13. De Deviti R, Spazinate R, Stella L, et al(1984) Surgery of the lumbar intervertebral disc: results of a personal minimal technique. Neurochirurgia 27:16 – 19
14. Ebeling U, Reulen HJ (1983) Ergebnisse der mikrochirur- gischen lumbalen Bandscheibenoperation – Vorläufige Mitteilung. Neurochirurgia 26:12 – 17
15. Ebeling U, Reulen HJ(1988) Mikrochirurgische Technik bei lumbalen Bandscheibenoperationen: Ist sie der kon- ventionellen Methode überlegen? In: Handbuch der Neu- rochirurgie 1988, Regensberg und Biermann, Münster, pp 143 – 160
16. EbelingU, Reichenberg W, Reulen HJ (1986) Results of mi- crosurgical lumbar discectomy. Review of 485 patients. Ac- ta Neurochir 81:45 – 52
17. Ferrer E, Garcia-Bach M, Lopez L, Isamat F (1988) Lumbar microdiscectomy: analysis of 100 consecutive cases. Its pit- falls and final results. Acta Neurochir Suppl 43:39 – 43 18. Finneson BE (1978) A lumbar disc surgery predictive score
card. Spine 3/2:186 – 188
19. Frenkel H, Angehoefer I (1978) Frühergebnisse nach lum- balen Bandscheibenoperationen. Beitr Orth Traumatol 25/
9:523 – 528
20. Goald HJ (1978) Microlumbar discectomy: follow-up of 147 patients. Spine 3/2:183 – 185
21. Goald HJ (1979) Microsurgical removal of lumbar herniat- ed nucleus pulposus. Surg Gynecol Obstet 149:247 – 248 22. Goald HJ (1981) Microlumbar discectomy: follow-up of
477 patients. J Microsurg 2:95 – 100
23. Grubb SA, Libscomb HJ, Guilford WB (1987) The relative value of lumbar roentgenograms, metrizamide myelogra- phy and discography in the assessment of patients with low back syndrome. Spine 12:282 – 286
24. Hudgins WR (1983) The role of microdiscectomy. Orthop Clin North Am 14:589 – 603
25. Jochheim KA, Loew F, Rütt A (eds) (1961) Lumbaler Band- scheibenvorfall. Springer, Berlin Heidelberg New York 26. Kahanovitz N, Viola K, McCulloch JA (1989) Limited sur-
gical discectomy and microdiscectomy: a clinical compari- son. Spine 14:79 – 81
27. Keyl W, Kossyk W, Kuzmann J, Weigert M, Muzzulini B (1974) Ergebnisse lumbaler Nukleotomien aus den Berli- ner und Münchner Orthopädischen Kliniken. Z Orthop 112:798 – 801
28. Kho HC, Steudel D (1986) Vergleich der mikrochirurgi- schen lumbalen Bandscheibenoperationen mit der kon- ventionellen Technik beim frei sequestrierten Bandschei- benvorfall. Eine retrospektive Studie anhand von 267 Fäl- len. Neurochirurgia 29:181 – 185
29. Kotilainen E, Valtonen S, Carlson CA (1993) Microsurgical treatment of lumbar disc herniation: follow-up of 237 pa- tients. Acta Neurochir (Wien) 120:143 – 149
30. Krämer J (1987) Das Postdiskotomiesyndrom-PDS. Z Or- thop 125:622 – 625
31. Love JG, Walsh MN (1938) Protruded intervertebral discs:
report of 100 cases in which operation was performed. J Am Med Assoc 111:396 – 400
32. Mayer G, Reiche P (1982) Ergebnisse der lumbalen Band- scheibenoperationen. Z Ärztliche Fortb (Jena) 76:190 – 194 33. McCulloch JA (1989) Principles of microsurgery for lum-
bar disc disease. Raven, New York
34. McCulloch JA, Young PH (eds) (1998) Essentials of spinal microsurgery. Lippincott-Raven, Philadelphia
35. Mixter WS, Barr IS (1934) Rupture of intervertebral disc with involvement of the spinal canal. N Engl J Med 211:
210 – 215
36. Nyström B (1987) Experience of microsurgical compared with conventional technique in lumbar disc operations.
Acta Neurol Scand 76:129 – 141
37. Oldenkott P (1971) Zur medizinischen und medizinisch- sozialen Problematik beim lumbalen Bandscheibenvor- fall. Habilitationsschrift, Tübingen
38. Oldenkott P (1979) Mikrochirurgische Behandlung lum- baler Wurzelkompressionssyndrome. Med Welt 30:1687 – 1691
39. Oppel F, Schramm J, Schirmer M (1977) Results and com- plicated courses after surgery for lumbar disc herniations.
In: Wüllenweber R, Brock M, Hamer J, et al (eds) Advances in Neurosurgery, vol 4, Springer, Berlin Heidelberg New York, pp 36 – 51
40. Oppenheim H, Krause F (1909) Über Einklemmung bzw.
Strangulation der cauda equina. Dtsch Med Wschr 35:
697 – 700
41. Probst C (1989) Lumbale Diskushernien: Mikrochirurgie – Ja oder Nein? Neurochirurgia 32:172 – 176
42. Sachs BL, Vanharanta H, Spivey MA, Guyer RD (1987) Dal- las discogram description: a new classification of CT/dis- cography in low-back disorders. Spine 12:287 – 293 43. Salenius P, Laurent LE (1977) Results of operative treat-
ment of lumbar disc herniation. A survey of 886 patients.
Acta Orth Scand 48:630 – 634
44. Schepelmann F, Greiner L, Pia HW (1977) Complications following operation of herniated lumbar discs. Adv Neuro- surg 4:52 – 54
45. Schmorl G, Junghanns H (1932) Die gesunde und kranke Wirbelsäule im Röntgenbild. Pathologisch-anatomische Untersuchungen. Thieme, Leipzig, pp 89 – 122
46. Schneiderman G, Flannigan B, Kingston S, Thomas J (1987) Magnetic resonance imaging in the diagnosis of disc degeneration. Spine 12:277 – 281
47. Schramm J, Oppel F, Umbach W, Wüllenweber R (1978) Komplizierte Verläufe nach lumbalen Bandscheibenope- rationen. Nervenarzt 49:26 – 33
48. Silvers HR (1988) Microsurgical versus standard lumbar discectomy. Neurosurgery 22:837 – 841
49. Spangfort EV (1972) The lumbar disc herniation. A com- puter-aided analysis of 2,504 operations. Acta Orth Scand Suppl 142:1 – 95
50. Steinke CR (1918) Spinal tumors: statistics on a series of 330 collected cases. J Nerv Ment Dis 47:418 – 426 51. Stolke D, Sollmann WP, Seifert V (1989) Intra- and postop-
erative complications in lumbar disc surgery. Spine 14:
56 – 59
52. Stookey B (1928) Compression of spinal cord due to ven- tral extradural chondromas: diagnosis and surgical treat- ment. Arch Neurol Psychiatry (Chicago) 20:275 – 291 53. Thomalske G, Galow W, Ploke G (1977) Critical comments
on a comparison of two series (1,000 patients each) of lum- bar disc surgery. In: Wüllenweber R, Brock M, Hamer J, et al (eds) Advances in Neurosurgery, vol 4, Springer, Berlin Heidelberg New York, pp 22 – 27
54. Thomas AMC, Afshar F (1987) The microsurgical treat- ment of lumbar disc protrusion. J Bone Joint Surg Br 69:
696 – 698
55. Tullberg T, Isacson J, Weidenhielm L (1993) Does micro- scopic removal of lumbar disc herniation lead to better re- sults than the standard procedure? Spine 18:24 – 27 56. Vogt KH (1974) Ergebnisse nach lumbaler Bandscheibeno-
peration. Z Orthop 112:821 – 822
57. Weber H (1978) Lumbar disc herniation. J Oslo City Hosp 28:33 – 64
58. Weber H (1983) Lumbar disc herniation. a controlled, pro- spective study with ten years of observation. Spine 8:131 – 140
59. Weber U, Sparmann M, Greulich A (eds) (1992) Orthopä- dische Mikrochirurgie. Thieme, Stuttgart
60. Weir BKA (1979) Prospective study of 100 lumbosacral discectomies. J Neurosurg 50:283 – 289
61. Wildförster U (1991) Intraoperative Komplikationen wäh- rend lumbaler Bandscheibenoperationen. Neurochirurgia 34:53 – 56
62. Wilkinson HA (ed) (1992) The failed back syndrome, 2nd edn. Harper and Rowe, New York
63. Williams RW (1978) Microlumbar discectomy. A conser- vative surgical approach to the virgin herniated lumbar disc. Spine 3:175 – 182
64. Williams RW (1986) Microlumbar discectomy. A 12-year statistical review. Spine 11:851 – 852
65. Wilson DH, Kenning J (1979) Microsurgical lumbar dis- cectomy: preliminary report of 83 consecutive cases. Neu- rosurgery 42:137 – 140
66. Wilson DH, Harbaugh R (1981) Microsurgical and stan- dard removal of the protruded lumbar disc: a comparative study. Neurosurgery 8:422 – 427
67. Wilson DH, Harbaugh R (1982) Lumbar discectomy: a comparative study of microsurgical and standard tech- nique. In: Hardy RW (ed) Lumbar disc disease. Raven, New York, pp 147 – 156
68. Wiltse LL, Fonseca AS, Amster J, Dimartino P, Ravessoud A (1993) Relationship of the dura, Hofmann’s ligaments, Batson’s plexus, and a fibrovascular membrane lying on the posterior surface of the vertebral bodies and attaching to the deep layer of the posterior longitudinal ligament.
Spine 18:1030 – 1043
69. Yasargil MG (1977) Microsurgical operation of herniated lumbar disc. In: Wüllenweber R, Brock M, Hamer J, et al (eds) Advances in Neurosurgery, vol 4, Springer, Berlin Heidelberg New York, pp 81 – 82
