Laminoplasty v. Laminectomy & Fusion CSRS Instructional Course Lecture Dec. 3, 2014 Orlando, FL John G. Heller, MD Emory Spine Center

It is helpful to understand how each of these surgical procedures evolved. The original operation for cervical myelopathy was a laminectomy. By the late 1970s it had become clear that a subset of laminectomy patients (20-30%) had poor outcomes due to post-laminectomy kyphosis, recurrent spinal cord compression, and/or pain. Scholars in different parts of the world sought to improve upon these results in different ways. North America was the birth place of anterior decompression and fusion. Japan evolved the laminectomy into what we know today as the laminoplasty family of procedures. Western Europe provided most of the original innovations in internal fixation of the cervical spine, both anteriorly and posteriorly. By the early 1990s surgeons began to add posterior segmental instrumentation and fusion to a laminectomy in order to prevent the possibility of kyphosis and its consequences.

The difference in the outcomes of these two operations is not with respect to neurology. It has been well established that they are equally effective in decompressing the spinal cord.7, 8, 13 With the addition of foraminotomies, nerve root decompression is also effective. They differ primarily in the complication and reoperation rates.

Motor root palsy was initially described in association with laminoplasty. Thus a misconception took root that it was a complication unique to laminoplasty. However, motor root palsy can occur following any of the procedures performed for cervical myelopathy: anterior10 or posterior. A recent large study29 established this, and oddly the rate was least among laminoplasty patients. It is not entirely clear whether there are effective measures available to reduce the incidence.18, 19, 20 But there has been a general trend toward reduced frequency over the last 25 years, which may reflect evolving anesthetic techniques or subtleties of surgical technique. Thus it is probably best to think of this as a complication of the disease, rather than the chosen treatment.

Postop sagittal alignment is sometimes offered as a differentiating feature. As it turns out, the mean effect on alignment with laminoplasty is essentially neutral.27 A large recent series actually showed a mean increase in lordosis of 2 degrees. Laminectomy and fusion theoretically maintains or improves lordosis. But this depends on the alignment fixed intraoperatively, which can be less lordotic than appreciated. Moreover, excessive correction can lead to iatrogenic foraminal stenosis and nerve root complications.28

Range of motion after the two procedures will be different. By definition, if all of the intended fusions heal, the laminectomy & fusion patient will have sacrificed more motion in pursuit of their treatment than the laminoplasty patient. This is especially true in the era of internal fixation and early active range of motion for laminoplasty patients. 28, 29 The older data regarding postop pain and stiffness came from a time when patients were required to wear hard collars for up to 3 months. 22, 23 In Japan, at that time, patients were often kept at bed rest for a month in hospital. Thus one might imagine the incidental facet fusions that occurred as a result. Internal fixation and early motion has not completely eliminated spontaneous facet or interlaminar fusion. But it less likely, as is acquired axial pain.

The primary distinguishing feature between the two operations is with respect to complication and reoperations rates, specifically for non-unions and/or implant failure among the fusion patients. This has been shown fairly consistently in the few direct comparison studies.9, 10, 11

Adjacent segment degeneration is a consideration among the fusion patients. But there are scant data on this issue. None the less, we have all treated such patients. Among laminoplasty patients, since they are not fused, the issue is a bit different. 30 They can develop nerve root compression from progessive osteophytes growth and foraminal stenosis with the decompressed region. This is also uncommon.

A word is also in order regarding comparative value. At this time in health care, we are compelled to consider cost and resource utilization for a given outcome. Studies have shown increased implant and total costs for laminectomy & fusion versus laminoplasty. 10 And under the current coding and reimbursement system in the U.S., there are significantly larger surgical fees associated with laminectomy & fusion.

Lastly, what about return to normal activity? The laminoplasty patient is encouraged to move their neck as much as possible, as soon as possible. Internal fixation reduces the risk of hinge closure and re-stenosis when engaging in early AROM postop.24, 31, 32 Active resisted neck, shoulder & arm training can begin 6 weeks postop. Most surgeons would advise against this until a fusion patient has had adequate time to properly heal, which is at least three months, if not six.

Though laminectomy & fusion clearly has its place/indications, among the majority of multi-level CSM and OPLL patients eligible for either procedure, the data favor laminoplasty on the basis of fewer complications, less cost and earlier return to normal activity. They are equivalent with respect to neurologic outcomes. References:

1. An Analysis of Factors Causing Poor Surgical Outcome of myelopathy due to OPLL: Anterior Decompression v. Laminoplasty: Masaki, et al. J Spinal Dis. & Tech. (2007)

2. Surgery for Cervical Myelopathy Due to OPLL Clinical results & limitations of L’plasty: Iwasaki, et al. SPINE (2007)

3. Surgical Strategy for Cervical Myelopathy Due to OPLL Anterior Surgery v. L’plasty: Iwasaki, et al. SPINE (2007)

4. Four level cervical corpectomy: Saunders et al: SPINE (1998)

5. Operative treatment of cervical spondylotic myelopathy and radiculopathy. A comparison of laminectomy and laminoplasty at five year average follow-up: Kaminsky SB, Clark CR, Traynelis VC: Iowa Orth. J. (2004)

6. Skip laminectomy--a new treatment for cervical spondylotic myelopathy, preserving bilateral muscular attachments to the spinous processes: a preliminary report. Shiraishi T , Spine J. (2002)

7. Posterior movement and enlargement of the spinal cord after cervical laminoplasty: Aita, et al: JBJS, (1998)

8. Lordotic alignment and posterior migration of the spinal cord following en bloc open- door laminoplasty for cervical myelopathy: a magnetic resonance imaging study: Baba, et al: J Neurol, (1996)

9. Laminoplasty vs. Laminectomy & Fusion for Multi-Level Cervical Myelopathy: an independent matched cohort analysis: Heller JG, Edwards, CC, Murakami H, Rodts GE: Spine (2001)

10. Treatment of Cervical Stenotic Myelopathy: a cost and outcome comparison of laminoplasty versus laminectomy and lateral mass fusion. Highsmith, et. al: J NSurg, (2011)

11. A prospective, randomized trial comparing expansile cervical laminoplasty and cervical laminectomy and fusion for multilevel cervical myelopathy. Manzano, et al: NSurg, (2012)

12. Local kyphosis reduces surgical outcomes of expansive open-door laminoplasty for cervical spondylotic myelopathy. Suda, et al: SPINE (2003)

13. Lordotic alignment and posterior migration of the spinal cord following en bloc open- door laminoplasty for cervical myelopathy: a magnetic resonance imaging study: Baba, et al: J Neurol, (1996)

14. Long term follow up studies of laminoplasty: Satomi et al, Spine (1994)

15. Laminoplasty for Failed Ant. Cervical Surgery Wang MY, et al.: Neurosurg. Focus (2003) PMID:15347225

16. Open-door laminoplasty for cervical myelopathy resulting from adjacent-segment disease in patients with previous anterior cervical decompression and fusion. Matsumoto, et al. SPINE (2006)

17. Long-term Outcome of laminectomy & Instrumented Fusion for Cervical OPLL: Chen Y, Guo Y, Chen D, et al: SICOT (2008)

18. C5 Palsy after Posterior Decompression & Posterior Fusion with Instrumentation: Takemitsu M, Cheung KMC, Wong YW, et al: JSDT (2008)

19.The incidence of C5 Palsy After Multilevel Cervical Decompression Procedures A Review of 750 consecutive cases: Nassr et al SPINE (2012)

20. Preventing C5 Palsy After Laminoplasty: Sasai et al. SPINE (2003)

21. Thickness o Subcutaneous Fat as a Risk Factor for Infection in Cervical Spine Fusion Surgery: Mehta et al JBJS (2013)

22. Neck and Shoulder Pain After Laminoplasty A Noticeable Complication: Hosono N, et al SPINE (1996)

23. The Source of Axial Pain after Cervical Laminoplasty: C-7 is More Crucial than Deep Extensor Muscles: Hosono N, et al: Spine (2007).

24. Risk Factors for Closure of Lamina after Open-Door Laminoplasty. Matsumoto M, et al: Spine (2008).

25. Laminoplasty vs. Laminectomy & Fusion for Multi-Level Cervical Myelopathy: an independent matched cohort analysis: Heller JG, Edwards, CC, Murakami H, Rodts GE: Spine (2001)

26. Cervical Alignment and Range of Motion After Laminoplasty Radiographical Data from more than 500 cases with Cervical Spondylotic Myelopathy and a Review of the Literature: Machino et al SPINE (2012)

27. Range of motion loss after cervical laminoplasty: a prospective study with minimum 5-year follow-up data: Hyun SJ, The Spine Journal (2013)

28. Interlaminar Bony Fusion After Cervical Laminoplasty: Its Characteristics and Relationship with Clinical Results: Lizuka H SPINE (2006)

29. Neurological Complications of Cervical Laminoplasty for Patients with Ossification of the Posterior Longitudinal Ligament-A multi-Institutional Retrospective Study: Seichi SPINE (2011)

30. Serial Changes in Signal Intensities of the Adjacent Discs on T2 Weighted Sagittal Images after Surgical Treatment of Cervical Spondylosis: Anterior Interbody Fusion versus Expansive Laminoplasty: Iseda, T. Acta Neurichir (Wien) (2001)

31. Laminar Closure After Classic Hirabayashi Open-Door Laminoplasty: Lee DH et al SPINE (2011)

32. Plate-Only Open Door Laminoplasty Maintains Stable Spinal Canal Expansion with High Rates of Hinge Union and No Plate Failures. Rhee et al SPINE (2010)

33. Lordotic alignment and posterior migration of the spinal cord following en bloc open- door laminoplasty for cervical myelopathy: a magnetic resonance imaging study: Baba, et al: J Neurol, (1996)

34. Long term follow up studies of laminoplasty. Satomi et al, Spine (1994)

35. Long-term Outcome of laminectomy & Instrumented Fusion for Cervical OPLL: Chen Y, Guo Y, Chen D, et al: SICOT (2008)

The FDA has not cleared the following pharmaceuticals and / or medical devices for the use described in this presentation. Posterior lateral mass screws are not approved for this use in the cervical spine by the FDA.