Inspired Spine- Minimally Invasive Direct Thoracic Interbody Fusion (MIS-DTIF)

• Hamid R. Abbasi, MD PhD FAANS • Board Certified Neurosurgeon • Tristate Brain and Spine Institute

• Ali B. Abbasi, BA MSci MPhil • Pritzker School of Medicine, The University of Chicago

H.R. Abbasi MD PhD FAANS (Present)

Zyga: Consulting, Research Study AMW Spine LLC: Research Grant, Consulting

(Past) Amendia: Consulting, ownership in distributorship

Ali Abbasi

Nothing to disclose

INTRODUCTION

DISCLOSURES

SMISS 2019 Hamid Abbasi MD PhD FAANS

Inspired Spine- Minimally Invasive Direct Thoracic Interbody Fusion (MIS-DTIF)

INTRODUCTION

Problems with current thoracic fusions • Lateral Approach: Thoracotomy with Rib removal • Posterior Approach: Facetectomy and removal of head of rib • Video-assisted thoracoscopic surgery is difficult to master • Common pulmonary complications: Hemothorax, Pneumothorax

Minimally Invasive Direct Thoracic Interbody Fusion (MIS-DTIF)

• Truly MI: no direct visualization • Approach without collapsing lung • Complemented with MIS pedicle screw fixation • Proof of Concept (4 cases) in this study

SMISS 2019 Hamid Abbasi MD PhD FAANS

Inspired Spine- Minimally Invasive Direct Thoracic Interbody Fusion (MIS-DTIF)

METHODS

Study Design: Proof of Concept, Establish Safety • Recorded surgery time, blood loss, hospital stay • Chest X-Ray and CT post surgery monitoring • 1 year follow up including pain score

Study Population: 4 patients, 6 spinal levels • All patients undergone full course of conservative therapy • Indications: Degenerative Disk Disease, Disk Herniation • Exclusion: Scoliosis, Hyperkyphosis, Scapula blocks approach

SMISS 2019 Hamid Abbasi MD PhD FAANS

Inspired Spine- Minimally Invasive Direct Thoracic Interbody Fusion (MIS-DTIF)

SURGICAL TECHNIQUE: APPROACH

1 1 Approach aided by A/P and Lat Fluoro + Electrophysiology • Enter a 8mm blunt canulated probe through an incision on

posterior axillary line. • Walk probe along the rib inside the pleural space and

position on disk of interest • Insert K-wire into disk space and working tube over K-wire,

creating sealed access to disk space

Left: (L to R) Probe, K wire, dilator, working tube, disk drill, rotating curette, ring curette, rongeur, cage insertion device. Right: Locating the incision point

SMISS 2019 Hamid Abbasi MD PhD FAANS

Inspired Spine- Minimally Invasive Direct Thoracic Interbody Fusion (MIS-DTIF)

SURGICAL TECHNIQUE: FUSION

SMISS 2019 Hamid Abbasi MD PhD FAANS

2

3

2 Discectomy performed through working tube • Remove disk material with drill, rotating curette, ring

curette, and rongeur • Prepare endplates by serial dilation of rotating curette • Pack disk space with Tricalcium Phosphate soaked in

autologous bone marrow aspirate

3 Cage entry • Remove working tube, replace K-wire • Insert cage over K-wire under biplanar Fluoroscopic

monitoring • Enter space into disk space with mallet until 1/3 of the

cage is past midline • Remove insertion devices, suture pleural space

4 Perform MI Posterior Pedicle Screw Fixation

Inspired Spine- Minimally Invasive Direct Thoracic Interbody Fusion (MIS-DTIF)

RESULTS

SMISS 2019 Hamid Abbasi MD PhD FAANS

Perioperative outcomes

Pain • Average pain reduced from 8.8 to 3.5 at 30 day follow up (p=0.121) and 5.3 at 1 year • Oswestry disability reduced from 47% pre op to 33% at 1 year follow up (p=0.131)

Complications • One patient: 1cm clinically insignificant hemothorax • Otherwise no hemothorax, pleural effusion, and pneumothorax (CAT scan

performed on all patients)

1One sided paired Wilcoxon Rank Sum test

Inspired Spine- Minimally Invasive Direct Thoracic Interbody Fusion (MIS-DTIF)

DISCUSSION

SMISS 2019 Hamid Abbasi MD PhD FAANS

Technical Notes • MIS-DTIF is the first truly MIS fusion of the thoracic spine

• Approach does not require collapsing a lung to access the spine • Disk space is sealed by access portal and can be freely packed with

TCP/biologic, this could lead to higher fusion rates.

Financial Considerations • MI surgeries cheaper due to shorter OR time, hospital stay and

fewer complications. • Unlike conventional approaches, MIS-DTIF can be done by a single

surgeon

Continuing Study • Disability Index, Fusion Rates • More complex cases: Higher spinal levels, patients with deformity

1 Rajaee (2012)

Inspired Spine- Minimally Invasive Direct Thoracic Interbody Fusion (MIS-DTIF)

SUMMARY

SMISS 2019 Hamid Abbasi MD PhD FAANS

Technique

Perioperative (4 patients) OR Time: 52min Hospital stay: 2.5d Bloodloss: 60ml

Clinical No significant complications Improvement on 1 year oswestry and pain

MIS-DTIF is a safe and effective fusion of the thoracic spine that is truly minimally invasive and technically straight forward