Prediction of Postoperative Clinical Outcome in Cervical Spondylotic Myelopathy

Česká verzia

Authors: D. Štěpánek; S. Žídek; D. Bludovský; M. Choc; V. Přibáň; I. Holečková
Authors place of work: LF UK a FN Plzeň
Published in the journal: Cesk Slov Neurol N 2014; 77/110(1): 39-46
Category: Original Paper

Summary

Objective:
In this retrospective study we outline the relationship between a chosen surgical approach as it relates to the localization of spinal cord lesion assessed by the use of evoked potentials and the effect of this approach on the postoperative state of patients with cervical spondylotic myelopathy.

Methodology:
The study, from 2006 to 2010, comprised 65 patients with clinical signs of cervical myelopathy. These patients had been indicated for surgery, which subsequently was performed by using either the anterior – A or posterior – P approach. The patients were assessed using Nurick and mJOA scores before surgery, then at 12, 24 months after surgery. In addition, they were preoperatively examined with a battery of evoked potentials (EP) – somatosensory evoked potential (SEP) and motor evoked potential (MEP) tests. Based on EP, principal spinal cord disability was determined: A – anterior (maximum changes in MEP), P – posterior (maximum change in SEP). The entire group was, on the basis of EP partitioning and the surgical approach used, divided into four groups: Aa, Ap, Pa, Pp. The results of individual examinations were compared within groups and in between groups.

Results:
Objective postoperative improvement mJOA score was found in all four groups. Statistically significant improvement was, however, detected only in the groups of anterior approaches regardless of the primacy of SEP or MEP lesion (Aa: p = 0.011, Ap: p = 0.005). Overall mJOA improvement was revealed in 65 % patients in this study.

Conclusion:
Objectively significant postoperative improvements were achieved with anterior approaches, regardless of the fact whether the dominant spinal cord pathology was located ventrally or dorsally. As a result of this study, there seems to be no benefit to choosing a surgical approach based on the localization of dominant spinal cord pathology assesses by EP.

Key words:
spondylotic cervical myelopathy – motor evoked potentials – somatosensory evoked potentials – surgical decompression

The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study.

The Editorial Board declares that the manuscript met the ICMJE “uniform requirements” for biomedical papers.

Zdroje

1. Bednařík J, Ambler Z, Růžička E. Klinická neurologie: část speciální II. 1st. ed. Praha: Triton; 2010: 711– 1277.

2. Mummaneni PV, Haid RW, Rodts GE. Combined ventral and dorsal surgery for myelopathy and myeloradiculopathy. Neurosurgery 2007; 60 (Suppl 1): S82– S89.

3. Kim PD, Ludwig SC, Gelb D, Poelstra K. Cervical Spine Update on the management of axial neck pain, cervical radiculopathy and myelopathy. Current Orthopaedic Practice 2008; 19(4): 425– 429.

4. Lu JJ. Cervical laminectomy: technique. Neurosurgery 2007; 60 (Suppl 1): S149– S153.

5. Kiris T, Killincer C. Cervical Spondylotic Myelopathy Treated by Oblique Corpectomy: A Prospective Study. Neurosurgery 2008; 62(3): 674– 682.

6. Stetkárova I, Kofler M. Cutaneous silent periods in the assessment of mild cervical spondylotic myelopathy. Spine 2009; 34(1): 34 – 42.

7. Lo YL. How has electrophysiology changed the management of cervical spondylotic myelopathy? Eur J Neurol 2008; 15(8): 781– 786.

8. Lo YL. The role of electrophysiology in the diagnosis and management of cervical spondylotic myelopathy. Ann Acad Med Singapore 2007; 36(11): 886– 893.

9. Takahashi J, Hirabayashi H, Hashidate H, Ogihara N,Yamazaki I, Kamimura M et al. Assessment of cervical myelopathy using transcranial magnetic stimulation and prediction of prognosis after laminoplasty. Spine 2008; 33(1): E15– E20.

10. Simó M, Arányi Z. Role of motor evoked potentials in the diagnosis of myelopathy associated with cervical spondylosis. Ideggyogy Sz 2003; 56(1– 2): 51– 57.

11. Nové‑ Josserand A, André‑ Obadia N, Mauguière F. Cervical spondylotic myelopathy: motor and somatosensory evoked potentials, clinical and radiological correlation. Rev Neurolog 2002; 158(12): 1191– 1197.

12. Simó M, Szirmai I, Arányi Z. Superior sensitivity of motor over somatosensory evoked potentials in the diagnosis of cervical spondylotic myelopathy. Eur J Neurol 2004; 11(9): 621– 626.

13. Bednařík J, Kadaňka Z, Dušek L, Kerkovsky M, Vohanka S, Novotny O et al. Presymptomatic spondylotic cervical myelopathy: an updated predictive model. Eur Spine J 2008; 17(3): 421– 431.

14. Kadaňka Z, Mareš M, Bednařík J, Smrcka V, Krbec M,Chaloupka R et al. Predictive factors for spondylotic cervical myelopathy treated conservatively or surgically. Eur J Neurol 2005; 12(1): 55– 63.

15. Kadaňka Z, Mareš M, Bednařík J, Smrcka V, Krbec M,Chaloupka R et al. Predictive factors for mild forms of spondylotic cervical myelopathy treated conservatively or surgically. Eur J Neurol 2005; 12(1): 16– 24.

16. Martín R, Carda JR, Montiaga F, Pinto JI, Sanz F, Paternina B et al. Cervical myelopathy: retrospective analysis of surgical results in 53 cases treated by anterior cervical discectomy and interbody fusion. Neurocirugia 2005; 16(3): 235– 255.

17. Kadaňka Z, Bednařík J, Novotný O, Urbánek I, Dušek L. Cervical spondylotic myelopathy: conservative versus surgical treatment after 10 years. Eur Spine J 2011; 20(9): 1533– 1538.

18. Nurick S. The natural history and the results of surgical treatement of the spinal cord disorder associated with cervical spondylosis. Brain 1972; 95(1): 101– 108.

19. Benzel EC, Lancon J, Kesterson L, Hadden T. Cervical laminectomy and dentate ligament section for cervical spondylotic myelopathy. J Spin Disord 1991; 4(3): 286– 295.

20. Kim Y, Kim Y, Ko Y. Myelopathy Caused by Soft Cervical Disc Herniation : Surgical Results and Prognostic Factors. J Korean Neurosurg Soc 2007; 42(6): 441– 445.

21. Cruccu G, Aminoff MJ, Curio G, Guerit JM, Kakigi R, Mauguiere F et al. Recommendations for the clinical use of somatosensory‑ evoked potentials. Clin Neurophysiol 2008; 119(8): 1705– 1719.

22. Groppa S, Oliviero A, Eisen A, Quartarone A, Cohen LG, Mall V et al. A practical guide to diagnostic transcranial magnetic stimulation: report of an IFCN committee. Clin Neurophysiol 2012; 123(5): 858– 882.

23. Wen S, Wong IO, Long MJ, Li J, Li X, Guo D et al. Effectiveness of Three Surgical Decompression Strategies for Treatment of Multilevel Cervical Myelopathy in Three Spinal Centres in China. Spine 2012; 37(17): 1463– 1469.

24. Kristof RA, Kiefer T, Thudium M, Ringel F, Stoffel M, Kovacs A et al. Comparison of ventral corpectomy and plate‑ screw‑ instrumented fusion with dorsal laminectomy and rod‑ screw‑ instrumented fusion for treatment of at least two vertebral‑ level spondylotic cervical myelopathy. Eur Spine J 2009; 18(12): 1951– 1956.

25. Di Lazzaro V, Restuccia D, Colosimo C, Tonali P.The contribution of magnetic stimulation of the motor cortex to the diagnosis of cervical spondylotic myelopathy. Correlation of central motor conduction to distal and proximal upper limb muscles with clinical and MRI findings. Electroencephalogr Clin Neurophysiol 1992; 85(5): 311– 320.

26. Chistyakov AV, Soustiel JF, Hafner H, Feinsod M.Motor and somatosensory conduction in cervical myelopathy and radiculopathy. Spine 1995; 20(19): 2135– 2140.

27. Hirai T, Okawa A, Arai Y, Takahashi M, Kawabata S, Kato T et al. Middle‑term results of a prospective comparative study of anterior decompression with fusion and posterior decompression with laminoplasty for the treatment of cervical spondylotic myelopathy. Spine 2011; 36(23): 1940– 1947.

28. Fehlings MG, Skaf G. A review of the pathophysiology of cervical spondylotic myelopathy with insights for potential novel mechanisms drawn from traumatic spinal cord injury. Spine 1998; 23(24): 2730– 2737.

29. Baptiste DC, Fehlings MG. Pathophysiology of cervical myelopathy. Spine J 2006; 6 (Suppl 6): S190– S197.

30. Shedid D, Benzel EC. Cervical spondylosis anatomy: pathophysiology and biomechanics. Neurosurgery 2007; 60 (Suppl 1): S7– S13.

31. Hirai T, Kawabata S, Enomoto M, Kato T, Tomizawa S, Sakai K et al. Presence of anterior compression of the spinal cord after laminoplasty inhibits upper extremity motor recovery in patients with cervical spondylotic myelopathy. Spine 2012; 37(5): 377– 384.

32. Epstein JA. The surgical management of cervical spinal stenosis, spondylosis, and myeloradiculopathy by means of the posterior approach. Spine 1988; 13(7): 864– 869.

33. Melvin, D, Law MD, Bernhardt M, White AA. Evaluation and Management of Cervical Spondylotic of Myelopathy. J Bone Joint Surg 1994; 76(9): 1420– 1433.

34. Rowland LP. Surgical treatment of cervical spondylotic myelopathy: time for a controlled trial. Neurology 1992; 42(1): 5– 13.

35. Kadanka Z, Bednarík J, Vohánka S, Vlach O, Stejskal L, Chaloupka R et al. Conservative treatment versus surgery in spondylotic cervical myelopathy: a prospective randomised study. Eur Spine J 2000; 9(6): 538– 544.

36. Shimomura T, Sumi M, Nishida K, Maeno K, Tadokoro K, Miyamoto H et al. Prognostic factors for deterioration of patients with cervical spondylotic myelopathy after nonsurgical treatment. Spine 2007; 32(22): 2474– 2479.

37. Sampath P, Bendebba M, Davis JD, Ducker TB. Outcome of patients treated for cervical myelopathy. A prospective, multicenter study with independent clinical review. Spine 2000; 25(6): 670– 676.