third annual ucsf techniques disclosures. smith- spino-pelvic... · large sva, no pt moderate sva /...

Justin Smith, MD, PhD

University of Virginia,

[email protected]

UCSF Techniques in Complex Spine Surgery

November 8-10, 2012

1

The Importance of Sagittal Spinopelvic Alignment

Justin S. Smith, MD, PhD

Associate Professor

Department of Neurosurgery

University of Virginia

Third Annual UCSF Techniques

in Complex Spine Surgery Disclosures

• Biomet: educational and development consultant

• Medtronic: consultant, research study group support

• DePuy: educational consultant, research study group support

• Globus: honorarium for educational course

• AANS/CNS Joint Spine Section: research grant support

Large variety of ‘deformities’

Adult Spinal Deformity

• Surgery that corrects neural impingement or spinal instability but causes poor sagittal or coronal alignment usually gives a bad result

Spinal Alignment



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November 8-10, 2012

2

Why is Global Spinal Alignment Important?

Jean Dubousset

Deviation from stable zone = Increase

muscular / energy use

Poor alignment = disability

•Must compensate for anatomic

deformation

• Mechanical disadvantage

challenges balance mechanisms

“Cone of Balance”

ODI=66

26 cm

ODI=7

58 y/o

690

22.8 cm

ODI=74



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November 8-10, 2012

3

ODI=13

• Plumbline Shift Anteriorly

=> Increasing disability

SF-12, SRS-29, ODI (p<0.001)

=> Lumbar kyphosis marked disability

SRS-29, ODI (p<0.05)

Glassman, Bridwell, Dimar, Horton, Berven, Schwab. SPINE 2005

Loss of Global Alignment

Pelvic retroversion

- acetabulum more anterior

Hip Extension

- for mild pelvic retroversion

Hip flexion/ Knee flexion

- in severe/fixed deformity

Courtesy of

Dr. Frank Schwab

Compensatory Mechanisms

The ‘Pelvic Vertebra’ J Dubousset

Regulator of

Alignment Link between

Above and

Below

Biospace / ENSAM

Courtesy of

Dr. Virginie Lafage

Alignment… More than just the spine



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November 8-10, 2012

4

SDSG Radiographic

Measurement Manual

Pelvic

Parameters

Pelvic

Incidence

SDSG Radiographic

Measurement Manual

(40°-65°)

Morphologic

Parameter

Pelvic Incidence

Morphological

parameter

Not Affected by

patient position

No Variation over

time in adult

population

Pelvic

Tilt

SDSG Radiographic

Measurement Manual

(10°-25°)

Compensatory

Parameter



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November 8-10, 2012

5

Pelvic Tilt

Positional

parameter

Compensatory

Mechanisms

Affected by

patient position

Sacral

Slope

SDSG Radiographic

Measurement Manual

(30°-50°)

Compensatory

Parameter

SDSG Radiographic

Measurement Manual

PI = PT + SS

Small PI

Vertical Sacrum

Flat Lordosis

Large PI

Horizontal Sacrum

Marked, long lordosis

Pelvic Incidence and Lordosis

Pragmatic

Estimate:

LL = PI +/- 10deg



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November 8-10, 2012

6

Same structural deformity … different compensation

Large SVA, No PT Moderate SVA / PT No SVA, Large PT

Pelvis = base of the spine, regulator of the standing

posture …. “Pelvic Vertebra”

• Prospective study was carried out on 125 adult patients with spinal deformity (mean age: 57 years)

• Correlation analysis between radiographic spinopelvic parameters and HRQOL measures was performed

Pelvic Tilt versus HRQOL Spino-Pelvic = Chain of Correlation

* Adult asymptomatic volunteers – Schwab, Lafage & al Spine 2006

r=0.81

r=0.79

r=0.57

r=0.47

Duval-Beaupere, Legaye, Vialle, Roussouly, Berthonnaud, ….



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November 8-10, 2012

7

Chain of correlation between PI and regional sagittal parameters. A large PI requires a large lumbar lordosis. An increase of lumbar lordosis is correlated with an increased

thoracic kyphosis which is correlated with an increased cervical lordosis.

Ames CP, Lafage V, Blondel B, Schwab F, et al. Spine (in press).

SVA = -52.87 + 5.90*(PI) – 5.13*(LLmax

)

– 4.45*(PT) – 2.09 * (TKmax

) + 0.57*(age)

Lafage V et al. Spine 36(13):1037-45, 2011.

125 patients

• Lafage Schwab

• Spine 2009

• All Curves

• SRS, ODI

• Xray & clinical analysis

• One site

492 patients

• ISSG

• SRS 2011

• All curves

• SRS, ODI

• Xray vs clinical correlation

• Multi-center

Prospective Analysis including Pelvis

What are the disability / pain generators ?

Schwab, Lafage, Shaffrey, Bess, Ames, Smith …

SpineView®

300 parameters

Does the Pelvis Matter? 125 ASD, Single site; Surgical / Non-operative

SpineView®

300 parameters

Correlations ?

Pelvic tilt and truncal inclination: two key radiographic parameters in the setting of adults with spinal deformity.

Lafage V, Schwab F, Patel A, Hawkinson N, Farcy JP.

Spine (Phila Pa 1976). 2009 Aug 1;34(17):E599-606.



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November 8-10, 2012

8

PI minus LL

LL

PI

• First most important parameter

• Correlation with

– SRS (appearance, activity, total)

– ODI (Walk, stand)

– SF12 (PCS)

• r-values

– 0.42<r<0.482

– p<0.000

SVA and T1SPI

• Second most important parameter

• Correlation with – SRS (appearance, activity, total)

– ODI

– SF12 (PCS)

• r-values – 0.40<r<0.46

• (p<0.0001)

• T1 tilt had greater correlation with HRQOL compared to SVA.

SVA

C7 T1

T1 Tilt

Pelvic Tilt

• Third most important parameter

• Correlation with – SRS (appearance, activity, total)

– ODI (Walk, stand)

– SF12 (PCS)

• Correlations with HRQOL – 0.37<r<0.41

– p<0.000

Note: Glassman reported SVA correlation <0.29

In

cre

ase

d R

etr

ov

ers

ion

T Thoracic only with lumbar curve < 30°

L TL / Lumbar only with thoracic curve <30°

D Double Curve with at least one T and one TL/L, both

> 30°

S Sagittal Deformity for coronal curve <30 ° AND

moderate to severe modifier(s)

4 Curves Type

Global Balance

0 : SVA < 4cm

+ : SVA 4 to 9.5cm

++ : SVA > 9.5cm

3 Modifiers

Pelvic Tilt

0 : PT<20°

+ : PT 20-30°

++ : PT>30°

LL minus PI

0 : within 10°

+ : moderate 10-20°

++ : marked >20°

SRS-Schwab Classification Schwab F, et al. Spine 37(12):1-6, 2012



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November 8-10, 2012

9

Alignment Objectives

SVA

C7 T1

T1 Tilt

<5cm <00

PT

<250 Proportional:

LL=PI +/- 90

Case Example

• 67 y/o M recently retired executive, R L5S1 PHL in past

• LBP severe when standing minimal when sitting

• Mild neurogenic claudication

• Has had trials PT, narcotics, ESIs, facet blocks

• VAS back: 8, VAS leg: 2

• ODI: 48

• Comes for 4th opinion

260

L2-3

L4-5

L3-4

L5-1

260

5.4 cm

PI=580

PT=360

LL=60



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November 8-10, 2012

10

Case 2. Surgical Approach?

1. Decompression Alone

2. Interspinous Spacers

3. Limited Decompression & Fusion

4. Transpsoas Anterior & MIS Posterior

5. Posterior Decompression and Posterolateral Fusion

6. Posterior Decompression & TLIF or PLIF

7. Circumferential Approach

5.4 cm

260

PI=580

PT=360

SRS

Classification

S Sagittal

Deformity

LL minus PI

++ : marked >20°

Pelvic Tilt

++ : PT>30°

Global Balance

+ : SVA 4 to 9.5cm

Alignment Objectives

SVA

C7 T1

T1 Tilt

<5cm <00

PT

<250 Proportional:

LL=PI +/- 90

Case 2. Surgical Approach?

1. Decompression Alone

2. Interspinous spacer

3. Limited Decompression & Fusion

4. Transpsoas Anterior & MIS Posterior

5. Posterior Decompression and Posterolateral Fusion

6. Posterior Decompression & TLIF or PLIF

7. Circumferential Approach



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November 8-10, 2012

11

Case. • Posterior T11 to

iliac with LS-S1 ALIF • VAS back: 0, VAS

leg: 0 • ODI: 8 • SRS-22: 4.6 • Classification: S, 0,

0, 0

36 mo

PT=180

PI=550

LL=470

Surgical Treatment of Pathological Loss of Lumbar Lordosis (Flatback) in the Setting of

Normal SVA Achieves Similar Clinical Improvement as Surgical Treatment for

Elevated SVA

Justin S. Smith, Manish Singh, Eric Klineberg, Christopher I.

Shaffrey, Virginie Lafage, Frank Schwab, Themi Protopsaltis,

David Ibrahimi, Justin K. Scheer, Greg Mundis, Munish Gupta,

Richard Hostin, Vedat Deviren, Khaled Kebaish, Robert Hart,

Doug Burton, Shay Bess, Christopher Ames

Presented at IMAST 2013

Vancouver, British Columbia

Background

• “Sagittal imbalance” (SVA >5cm) is a recognized driver of disability and a primary indication for surgical correction

SVA = +21cm

PI-LL = 54°

• Multiple studies have demonstrated improvement in HRQOL with correction of “sagittal imbalance”

SVA = +3.9cm

PI-LL = 5° Background

• Subset of patients with sagittal spino-pelvic malalignment and flat back deformity but remains sagittally compensated with normal SVA

• Few data exist for patients with “compensated flatback” (SVA <5cm, PI-LL >10°)

SVA = +1.6cm

PI-LL = 25°

• Does surgical treatment offer improvement in HRQOL?



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November 8-10, 2012

12

Objective

To compare baseline disability and treatment outcomes for patients with sagittal spino-pelvic malalignment who are:

•

Compensated

(PI-LL>10° & SVA<5cm)

Decompensated

(SVA>5cm)

▪

▪

Patient Population

Parameter

SVA > 5cm

(n=98)

SVA <5cm &

PI-LL >10°

(n=27)

P-value

Mean age, years (SD) 62.9 (12.4) 55.1 (12.1) 0.004

Gender, percent women 76 93 0.063

Mean BMI (SD) 28.6 (5.1) 26.6 (5.9) 0.097

Mean Charlson

Comorbidity Index (SD) 1.6 (1.7) 1.1 (1.2) 0.083

Mean pain score, 0-10 (SD)

Back pain 7.7 (2.0) 6.8 (2.4) 0.060

Leg pain 4.6 (3.2) 4.6 (3.6) 0.97

Change from Baseline to 1yr Decompensated Group

P<0.001

P<0.001

P<0.001

P<0.001 P<0.001

Change from Baseline to 1yr Compensated Group

P=0.005

P<0.001 P=0.009

P=0.034 P<0.001



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November 8-10, 2012

13

Change from Baseline to 1yr Decompensated Group

All comparisons: P<0.001

Change from Baseline to 1yr Compensated Group

All comparisons: P<0.007

Change from Baseline to 1yr

All comparisons: P>0.24

Percent Reaching MCID

P=0.49

P=0.42

P=0.98

P=0.28 P=0.15

P=0.87



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November 8-10, 2012

14

Smith et al, submitted (2013).

Global Spinal Alignment: Summary

• Whether treating primary malalignment or in association with scoliosis, goals for alignment:

SVA <5cm PT<25° PI-LL ± 9°

• Surgical treatment for ASD that leaves the patient with poor sagittal spino-pelvic alignment (despite

successfull decompression and fusion) is likely to have poor long-term results

• Achieving adequate sagittal spino-pelvic alignment is key for obtaining improved HRQOL

• Sagittal spino-pelvic malalignment is associated with poor HRQOL, including pain and disability

Thank You

third annual ucsf techniques disclosures. smith- spino-pelvic... · large sva, no pt moderate sva /...

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