Advances In Minamilly Invasive Spine Surgery: Minimally invasive - PowerPoint PPT Presentation

Advances In Minamilly Invasive Spine Surgery: Minimally invasive spinal posterior decompression surgery using endoscope for cervical disorders Akihito Minamide, MD, PhD*; Andrew K. Simpson, MD, MHS** Munehito Yoshida, MD, PhD*; Hiroshi Yamada, MD, PhD* *Department of Orthopaedic Surgery, Wakayama Medical University, Wakayama, Japan ** Texas Back Institute, Dallas, TX, USA Orthopaedic Summit 2017: Evolving Techniques in the Spine Session Las Vegas, NV, USA, December 6-9, 2017

Orthopaedic Summit 2017: Evolving Techniques Spine Session Advances In Minamilly Invasive Spine Surgery Akihito Minamide, MD (n) Nothing Authors’ disclosure statement: The authors report no actual or potential conflict of interest in relation to this article. 和歌山県立医科大学 WAKAYAMA MEDICAL UNIVERSITY

Microendoscopic Spinal Surgery has developed with Special 1999 1996 2005 METRx-MED MED Optical tools Instruments System Foley KT Hi-Vision Kerrison's rongeurs development Drill Smith MM camera 3CCD camera SONOPET Curved Kerrison's rongeurs Midas Legend system Curved high-speed drill Ultrasonic Knife “SNOPET”

Progress of Video Image Contribution to the development of microendoscopic spinal surgery 3mm endoscope 4mm endoscope disposable endoscope 1CCD camera 3CCD camera Hi-vision camera 1996- 1999- 2005- 和歌山県立医科大学 WAKAYAMA MEDICAL UNIVERSITY

Perspective of viewing modality E ndo sc o pe Endoscope-assisted Microscope- Co nve ntio na l assisted - OPE N positioned - Mic ro sc o pe outside the skin places the perspective inside the tube The endoscopic surgery allows us to clearly visualize the ipsilateral and contralateral recesses and more effectively perform the decompression.

Indications of Microendoscopic Spinal Decompression Surgery  Lumbar disc herniation  Lumbar spinal stenosis degenerative spondylolisthesis degenerative scoliosis  Lumbar isthmic spondylolisthesis  Thoracic myelopathy spondylosis, OYL  Cervical myelopathy or radiculopathy etc. spondylosis, disc herniation, CYL 和歌山県立医科大学 WAKAYAMA MEDICAL UNIVERSITY

Application of Microendoscopic Laminotomy for Cervical Myelopathy 和歌山県立医科大学 WAKAYAMA MEDICAL UNIVERSITY

Cervical Microendoscopic Laminotomy (CMEL) The patient is turned to the prone position, and is fixed in a Mayfield head holder. The neck position is a neutral or slightly flexion. Inter-lamina space The tubular retractor is put on the lamina and facet joint.

Cervical Microendoscopic Laminotomy (CMEL) Minamide A. Eur Spine J 19:487-493,2010. Developing to the bilateral decompression surgery by the unilateral approach

Pathomechanism of CSM Pincer mechanism  Compression of the spinal cord is observed in the articular segment.  A bulging disc compresses the spinal cord anteriorly.  The hypertrophied ligamentum flavum compresses the spinal cord posteriorly. Otani K, et al. Spine 34(3): 268-273, 2009. 和歌山県立医科大学 WAKAYAMA MEDICAL UNIVERSITY

Cervical Spondylotic Myelopathy (CSM)  A segmental partial laminectomy for CSM: Showed the same clinical outcomes in comparison with comventional expansive laminoplasty. (Otani K, et al. Spine, 2009) Posterior segmental articular decompression 和歌山県立医科大学 WAKAYAMA MEDICAL UNIVERSITY

Surgical Methods  Posterior shift of spinal cord with conventional LAP: OPLL  Segmental articular decompression: CSM Surgical methods include ……. • Segmental Partial Laminectomy (Ohtani K. Spine 2009) • Skip Laminectomy (Shiraishi T. Spine 2003) • Microendoscopic Laminotomy (CMEL) CMEL

Case: 74 y.o Female Clumsiness, numbness in her hands, and spastic gait Pre-Op. JOA = 12/17 CMEL surgery ： C3/4,4/5, 5/6 2 years after surgery Before surgery JOA = 14/17

CT scan The laminotomy are done at each level by the unilateral approach .

Clinical outcomes of CMEL surgery for CSM patients ……. Questions: 1. How is the difference in clinical outcomes between CMEL and conventional expansive laminoplasty? 2. Also, is there a difference in the long-term clinical outcomes between two groups? 3. Is it possible for CMEL to respond to cases of spinal cord compression due to anterior factors? 和歌山県立医科大学 WAKAYAMA MEDICAL UNIVERSITY

Question 1 Minamide A, et al. Spine 40, 1807-1815, 2015. Minamdie A, et al. J Neurosurg Spine 27(2), 2017.  To investigate the long-term clinical and radiological results of CMEL surgery (articular segmental decompression using endoscopy) for CSM patients and to compare outcomes to conventional expansive laminoplasty (ELAP).

Study Design Retrospective case-controlled study using propensity score matching: This retrospective case–control study of the clinical outcomes of CMEL and ELAP for the treatment of CSM used the propensity score matching method.  A one-to-one matching analysis was performed between patients who underwent ELAP and CMEL on the basis of the estimated propensity scores of each patient.  Patients were matched according to calculated propensity scores in a logistic regression model adjusted for age, sex, and preoperative severity of disorder (JOA score).  A nearest-neighbor matching procedure was used, with the restriction that the propensities matched had to be within 0.05 units of each other.

Results Nachi Shrine World Heritage in Wakayama Kumano Shrine

Characteristics of each group on matching by the calculated propensity score ELAP CMEL P value Patients 71 pts 71 pts Sex M 47, F 24 M 47, F 24 63.8 ± 11.7 62.8 ± 13.7 Age 0.645 10.1 ± 2.4 10.2 ± 2.6 Preoperative JOA 0.96 2.0 ± 0.8 3.9 ± 0.3 Surgical levels <0.0001

Clinical outcomes on each surgical procedure at the 2-year follow-up ELAP CMEL P value 13.9 ± 2.1 14.1 ± 1.9 JOA 0.485 JOA recovery 56.3 ± 22.2 62.8 ± 13.7 0.349 rate VAS for axial 42.8 ± 32.4 24.5 ± 25.6* 0.001 symptoms Satisfaction 7.8 ± 2.1 8.5 ± 1.8* 0.036 for surgery

Influence of surgical techniques on soft tissues Finger Surgery ELAP 1 or 2 level(s) 4 levels CMEL CMEL The microendoscopic surgery is much more different in the involvement to soft tissues than the conventional approach.

Subaxial cervical lordosis between C2 and C7 angle on lateral radiograph CMEL ELAP P value 12.7 ± 15.1 O 10.0 ± 8.3 O Pre-operation 0.45 5-year 14.9 ± 15.8 O 7.9 ± 9.5 O *0.042 follow-up Differences between 2.6 ± 7.7 O -1.2 ± 5.0 O *0.031 pre- and 5 years There were significant differences in the lordotic differences pre- and postoperatively between two groups (p<0.05). CMEL surgery maintained postoperative cervical lordosis.

Summary (1)  This 5-year follow-up data demonstrates that after undergoing CMEL surgery, patients have similar neurological outcomes to conventional laminoplasty, with significantly less postoperative axial pain and improved subaxial cervical lordosis.  CMEL for CSM is indicated for posterior decompression of the articular segment along with a pincer mechanism.  This minimally invasive technique may have potential advantages compared with conventional ELAP, and may provide an alternative surgical option.

Question 2 Is it possible for CMEL to respond to cases of spinal cord compression due to anterior factors?  To investigate the regression of cervical disc in patients, who underwent CMEL surgery, on pre- and post-operative MRI.  Based on this result, to reconsider about the indication of CMEL.

Cervical myelopathy with CDH What is your surgical strategy ? 50 y.o. Woman  Neck pain  Numbness in both hand  Clumsiness in finger motions  Spastic gait  Urinary disturbance  JOA score: 13/17

Cervical myelopathy with CDH What is your surgical strategy ? 50 y.o. Woman 1. ACDF  Neck pain 2. Posterior decompression  Numbness in both - laminoplasty hand - laminectomy and fusion  Clumsiness in finger motions  Spastic gait  Urinary disturbance  JOA score: 13/17

Cervical myelopathy with CDH What is your surgical strategy ? 50 y.o. Woman 1. ACDF  Neck pain 2. Posterior decompression  Numbness in both - laminoplasty hand - laminectomy and fusion  Clumsiness in finger motions  Spastic gait We pla ne d po ste rio r  Urinary de c o mpre ssio n b y CME L disturbance surg e ry.  JOA score: 13/17

Cervical myelopathy with CDH What is your surgical strategy ? 50 y.o. Woman 1. ACDF  Neck pain 2. Posterior decompression  Numbness in both - laminoplasty hand - laminectomy and fusion  Clumsiness in finger motions  Spastic gait We pla ne d po ste rio r  Urinary de c o mpre ssio n b y CME L disturbance surg e ry.  JOA score: 13/17

6 months after CMEL surgery JOA score = 16/17 Regression of disc herniation!!

Cervical Disc Herniation  Anterior cervical discectomy and fusion (ACDF) Smith GW et al. JBJS (Am ), 1958 Cloward RB J Neurosurg Spine, 2007  Regression of soft disc herniation after cervical laminoplasty Iwasaki M, et al. Spine 21(1):32-38, 1996. Yoshida M, et al. Spine, 23(2): 2391-7, 1998. • Laminoplasty provide equal neurologic improvement as ACDF. • Changes of dural pulsation after cervical laminoplasty may play a role in regression of CDH.