Poster Presentation 51st International Society for the Study of the Lumbar Spine Annual Meeting 2025

Lumbar facet angle tropism and hand and foot dominance in patients with early stage spondylolysis using a 3D bone model (#203)

Shiro Sugiura 1 2 3 , Yasuchika Aoki 4 , Kazuya Ito 5 , Takeshi Toyooka 1 , Tetsuo Shiga 1 , Taiki Takeda 1 , Kazuhide Inage 6 , Masahiro Inoue 6 , Kohei Okuyama 1 6 , Kinshi Kato 3 , Kazuyoshi Gamada 7 , Yuzuru Okamoto 1 , Seiji Ohtori 6 , Satoru Nishikawa 1
  1. Nishikawa Orthopaedic Clinic, Chiba-ken, SAKURA-SHI, Japan
  2. Department of Bioenvironmental Medicine, Graduate School of Medicine, Chiba University, Chiba, Japan, Chiba
  3. Department of Orthopaedic Surgery, Fukushima Medical University School of Medicine, Fukushima City, Fukushima, Japan, Fukushima
  4. Department of Orthopaedic Surgery, Eastern Chiba Medical Center, Chiba, Japan, Chiba
  5. Takeda Orthopaedic Clinic, Hyougo
  6. Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan, Chiba
  7. GLAB Corp, Hiroshima

INTRODUCTION

Early-stage lumbar spondylolysis (ESS) is a common disease in adolescent patients. A two-dimensional analysis revealed that laterality of facet joints affect spondylolysis1). This study sought to investigate the relationship between the laterality of both facet joints, hand/foot dominance and very early to early-stage ESS patients using a three-dimensional (3D) bone model.

METHODS

We evaluated 70 pediatric patients (55 males, 15 females; <19 years old) who were diagnosed with unilateral very early or early ESS through magnetic resonance imaging and computed tomography (CT). A 3D surface model of the lumbar spine was created by segmenting the contours of the vertebral column using DICOM data of CT images. Local coordinate systems for the superior and inferior articular auricular surfaces of the right and left facets were defined and investigated facet orientation by that angle. We also investigated the relationship between the hand/foot dominance and affected side of ESS. Differences between the laterality of facet morphology, hand/foot dominance, and affected side of ESS were investigated using a paired-sample t-test.

RESULTS

The average range of the right/left superior articular process was 43.0 ± 12.4/43.1 ± 12.0°. The average range of the right/left inferior articular process was 45.9 ± 12.4/44.9 ± 11.6°. The average range of the affected side of the ESS superior/inferior articular process was 42.9 ± 12.5/43.2 ± 11.8 degrees. The average range of the affected side/unaffected side of the ESS inferior articular process was 45.2 ± 12.2/45.7 ± 11.8°. The average range of the dominant/non-dominant hand-side superior articular process was 42.6 ± 12.4/43.1 ± 12.2°. The average range of the dominant hand-side inferior articular process was 45.6 ± 13.2/45.9 ± 11.5°. The average range of the dominant foot/non-dominant foot-side superior articular process was 42.1 ± 12.6/42.9 ± 11.8°. The average range of the dominant/non-dominant foot-side inferior articular process was 45.1 ± 12.6/45.7 ± 11.6°. No significant differences were found for all values.

DISCUSSION

This study investigated facet joint laterality in unilateral spondylolysis using a 3D bone model. Our study demonstrated that facet angle laterality was not a predisposing factor for very early to early-stage ESS. In addition, we found no evidence of a relationship between facet laterality and hand or foot dominance. Therefore, we believe that it is difficult to predict which side ESS occurs based on morphological left–right differences in intervertebral joints and hand or foot dominance. It is crucial to enhance environmental factors, such as an athlete’s physiological capacity and the frequency of sports field practice, in order to prevent the development of ESS given the minimal impact morphological factors have on the development of this condition.