1. MIS Techniques Applied to Deformity:
James D. Schwender M.D.
Past President Society of Minimally Invasive Spine Society
Twin Cities Spine Center
Minneapolis, MN
USA

2. FACTORS to CONSIDER: Pre-operative Surgical Planning
SURGICAL OBJECTIVES:
DEFORMITY CORRECTION
Sagital and coronal
DECOMPRESSION NEEDS
BONE QUALITY
PATIENT COMORBIDITIES
FUSION TECHNIQUES
Interbody, Facet, Posterolateral

3. THE MIS TECHNIQUE FOLLOWS THE SEVERITY OF PATHOLOGY
TLIF and DLIF or OLIF with percutaneous screws
Trans
psoas
MIS TLIF

4. Pre-operative imaging
Review plain radiographs and advanced imaging to determine the approximate diameter of the pedicle and lengths required
Especially in the midthoracic and upper lumbar levels
Advanced imaging (O-arm, robotics) maybe helpful if significant deformity or revision procedures

5. Screw Trajectory
Open
MIS
Objective # 5 5 5

6. Percutaneous Screw Placement Advantages
Improved pullout characteristics
Screw-head more lateral avoiding boney obstacles ( facet joint, SP)
? Less adjacent segment disease
Easier rod insertion

7. Methods to reduce Inter-operative X-ray exposure
Always wear protective lead including thyroid shield
Move as far away from the C-arm as possible
No ‘live’ fluoroscopy
Trust yourself!
Advanced imaging
Mini-open techniques. Combining direct visualization of screw starting point with perc. technique

10. Role of Interbody Techniques: TLIF and Transpsoas
Correction of coronal and sagittal balance
Increased fusion rates
Less pedicle screw failure
Load sharing

11. PREFERRED Trans-psoas APPLICATIONS
L4-5 and above
Single and multiple level involved
Deformity correction
Sagital > 15 degrees per level
Coronal deformity
Indirect decompression alone is acceptable
Obesity where MIS-TLIF approach is >8cm depth

12. Oblique Lateral OLIF Can be used at all levels lumbar spine
No need for entry through the psoas
Less risk to the lumbar plexus
In many cases spine surgeons still use vascular surgeon exposure
Remains difficult at L5-S1

13. PREFERRED MIS TLIF APPLICATIONS
END OF LONG SEGMENT POSTERIOR FUSIONS
DESIRE INTERBODY FUSION WHERE HIGH RISK PSEUDOARTHROSIS LEVELS
LUMBOSACRAL JUNCTION L4-5-S1
SEVERE STENOSIS REQUIRING FORMAL DECOMPRESSION
MODERATE LOCAL SAGITAL DEFORMITY CORRECTION
LESS THAN 10 DEGREES SAGITAL CORRECTION PER LEVEL.

14. Pre-op Planning Left or right side approach?
In most cases it doesn’t matter
Go in on side that appears easiest to access on x-rays (e.g., due to crest, ribs, collapse, etc.)
Correction can be equally good from either side; consider ease of access
Surgeon comfort
approaching from the convex side will make disc localization easier but may make L4-5 problematic
…approaching from the concavity will make L4-5 easier but may make levels near the apex more difficult to find

15. Hybrid Construct for Deformity
64 yo with mild scoliosis
chronic renal failure, DM, CHF, heart dz, COPD.
LBP and LE pain due to foraminal stenosis 15

21. Surgical Plan DLIF L2-3, L3-4 and possible L4-5 TLIF L4-5 and L5-S1
Percutaneous Pedicle screw placement L1-S1
Decompression L3-S1
Facet (Posterior) fusion L1-S1

25. 68 yo healthy female Progressive deformity
Worsening psuedoclaudication symptoms

26. G.H. 08/2009

27. G.H. 8/2012

28. G.H. 7/2012

29. Surgical Plan Stage 1 Stage 2
Lateral transpsoas approach L1-2, 2-3, 3-4
Stage 2
TLIF L4-5, L5-S1
Perc screws

30. G.H. 11/2012

31. G.H. 11/2012

32. 4 weeks later

33. G.H. 12/2012

34. G.H. 12/2012

35. G.H. 6/2013

36. CONCLUSIONS Current technique (Hybrid Construct)
DLIF L3-4 and above where formal decompression is not required
MIS TLIF at L4-5 and L5-S1
Tubular retractor facet joint fusion at all levels of the construct
Segmental percutaneous pedicle screw construct
+/- iliac fixation
Same day when patient is healthy

37. Thank You