Loss of lumbar lordosis affects the proximal spine first

Thursday, June 1, 2023

8:30 AM – 6:15 PM

Location: Salons 7-8

Presenting Author (Person doing the Podium Present(s)

JE

Jonathan Elysee

Lenox hill Hospital, Northwell Health, United States

Co-Author(s)

BJ

Bongseok Jung

Albertson, New York, United States
JM

Joshua Mathew

Floral Park, New York, United States
BS

Basel Sheikh Alshabab

United States
PD

Priya Duvvuri, BA

United States
JF

John Fallon

Medical Student
Northwell Health, United States
AK

Austin Katz, MD

Northwell Health, United States
JS

Junho Song

United States
AS

Adam Strigenz, BA

Medical Student
Zucker School of Medicine at Hofstra/Northwell
Westbury, New York, United States
LZ

Luke Zappia

United States
RL

Renaud Lafage, MS

Senior Biomedical engineer
Lenox Hill Hospital
new york, New York, United States
Virginie Lafage, PhD

AVP, Clinical Research
Lenox Hill | Northwell
Hospital for Special Surgery
New York, New York, United States

View E-Poster
SV

Sohrab Virk, MD, MBA

Fellow
Northwell Health
New York, New York, United States

Submitter(s)

Virginie Lafage, PhD

AVP, Clinical Research
Lenox Hill | Northwell
Hospital for Special Surgery
New York, New York, United States

View E-Poster

Introduction:
The research landscape on regional lumbar alignments has evolved rapidly with a specific focus on loss of lordosis. However, few studies have attempted to characterize how and where lumbar lordosis (LL) is lost.

AIMS/

Objectives:
To quantify how much LL is lost in the proximal and distal lumbar spine in patients with degenerative spine disease, and how this may relate to muscle health.

Methods:
This is a retrospective, single surgeon analysis. Spino-pelvic parameters and disc heights were collected. MRI-based multifidus characteristics including cross sectional area (CSA), lumbar indentation values, and Goutallier classification scores were assessed.

After describing the classic parameters, the cohort's normative L1PA, L4PA, global and regional lordosis were calculated using age-and PI-adjusted formulas. PI-LL offsets from norm were used to create 3 alignment groups: 74 patients with Mild(Mld), 55 pts with Moderate(Mod), and 26 pts with Severe(Sev) mismatch. The range of motion(ROM) of L1-S1, L1-L4, L4-S1 were calculated from flexion/extension films. The 3 alignment groups were then analyzed and compared.

Results:
155patients with degenerative lumbar pathologies were included (age 56±16, BMI 29.26±5 kg/m^2, 57% F) with the following sagittal alignment: PI=55.4±10°, PI-LL=8.35±11°, PT=20.62±8°, L4-S1=30.6±9°, L1PA=11.17±7°, and L4PA=11.44±4°. Compared to age-and-PI adjusted values, our cohort had a loss of LL (ΔPI-LL: 12.0±9°) due to both proximal and distal segments(ΔL1-L4: -7.1±8°; ΔL4-S1: -4.5±9°) leading to a more anterior spine (ΔL1PA:1.0±5°; ΔL4PA:0.4±2)(all p< 0.01). The 3 alignment groups had no differences in sex (p=0.14), age (p=0.667), and PI (p=0.658).

Compared to the Norm, patients in “Mld” (PI-LL offset from norm=4.1±3°) had a significant loss of LL in the proximal segments (L1L4: 20.2° vs 23.9° p< 0.01) but none distally (L4S1: 35.3 vs 35.2 p=0.9); they also had a slight anterior translation of L1 (L1PA: 8.2°vs 7.8° p=0.041).

Patients in “Mod” (PI-LL offset from norm=14.4±3°) had 8.5° loss in the proximal segments (L1L4: 14.6° vs 23.1° p< 0.001) and 3.8° in the distal segments (L4S1: 29.1° vs 34.8° p< 0.001); L1 vertebra translated anteriorly (L1PA: 11.6°vs 7.8 p< 0.001) but not L4 (L4PA: 11.3° vs 10.7° p=0.06).

Patients in “Sev” (PI-LL offset from norm=29.4±6°) had a 14° loss of lumbar lordosis both in the proximal (L1L4: 9.8° vs 23.8°) and distal segments (L4S1: 20.4° vs 35.2°); the lumbar spine translated anteriorly as showed by L1PA (17.9° vs 7.8°, p< 0.001) and L4PA (13.2 vs 11.1, p< 0.001). The “Sev” patients also had a smaller L4-L5 disc heigh (9.03 vs. 11.05mm p< 0.01), less ROM at L4S1 (6.3±5° vs 10.0±6° vs 11.0±7° p< 0.001), without significant difference in L1S1 ROM.

There was no significant differences across groups in muscle CSA (4332 vs 4051 vs 4396, p=0.332) or Goutallier classification (p=0.412), but there was a significant difference in Lumbar Indentation between “Mld” and “Mod" (14 vs 10, p=0.02).

Conclusions:
Our study showed that in a degenerative population the loss of lumbar lordosis begins proximally and progresses to affect the distal portion of the curve. Furthermore, we noticed that the loss in curvature distally is characterized by the spine translating anteriorly, a reduction in disc space and a loss in distal range of motion.