Thoracic Deformity Correction and Changes of Vital Capacity, Forced Expiratory Volume in 1 Second, and Expiratory Flow in Adolescent Idiopathic Scoliosis Five Years or More after Posterior Spinal Fusion with Thoracoplasty

Tsutomu Akazawa; Masahiro Iinuma; Shingo Kuroya; Yoshiaki Torii; Tasuku Umehara; Kenichi Murakami; Toshiaki Kotani; Tsuyoshi Sakuma; Shohei Minami; Sumihisa Orita; Kazuhide Inage; Kazuki Fujimoto; Yasuhiro Shiga; Junichi Nakamura; Gen Inoue; Masayuki Miyagi; Wataru Saito; Seiji Ohtori; Hisateru Niki

doi:10.22603/ssrr.2018-0075

Thoracic Deformity Correction and Changes of Vital Capacity, Forced Expiratory Volume in 1 Second, and Expiratory Flow in Adolescent Idiopathic Scoliosis Five Years or More after Posterior Spinal Fusion with Thoracoplasty

Spine Surg Relat Res. 2018 Dec 1;3(3):222-228. doi: 10.22603/ssrr.2018-0075. eCollection 2019.

Authors

Tsutomu Akazawa^{1

2}, Masahiro Iinuma¹, Shingo Kuroya¹, Yoshiaki Torii¹, Tasuku Umehara¹, Kenichi Murakami¹, Toshiaki Kotani², Tsuyoshi Sakuma², Shohei Minami², Sumihisa Orita³, Kazuhide Inage³, Kazuki Fujimoto³, Yasuhiro Shiga³, Junichi Nakamura³, Gen Inoue⁴, Masayuki Miyagi⁴, Wataru Saito⁴, Seiji Ohtori³, Hisateru Niki¹

Affiliations

¹ Department of Orthopaedic Surgery, St. Marianna University School of Medicine, Kawasaki, Japan.
² Department of Orthopedic Surgery, Seirei Sakura Citizen Hospital, Sakura, Japan.
³ Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan.
⁴ Department of Orthopaedic Surgery, Kitasato University School of Medicine, Sagamihara, Japan.

Abstract

Introduction: The purpose of this study is to investigate thoracic deformity correction and pulmonary function changes in patients with adolescent idiopathic scoliosis (AIS) five years or more after undergoing posterior spinal fusion with thoracoplasty for correction of a thoracic deformity.

Methods: Subjects were 57 patients with AIS who underwent posterior spinal fusion between 2004 and 2010. 24 patients who had undergone thoracoplasty at least five years earlier agreed to participate in this research. X-rays, pulmonary function tests, and thoracic cage computed tomography (CT) were performed, and the Scoliosis Research Society Outcomes Questionnaire (SRS-22) was administered. CT axial images were used at the apex of the main thoracic (MT) curve. Apical vertebral rotation was evaluated using rotation angle to the sagittal plane (RA_sag). Thoracic deformities were evaluated using the rib hump index (RHi) and the posterior hemithoracic symmetry ratio (PHSr).

Results: There were no significant differences between the preoperative and the final observation forced vital capacity (FVC) or the preoperative and the final observation %FVC. The forced expiratory volume in 1 s (FEV1) and %FEV1 were significantly improved at the final observation: FEV1 (preoperative: 1.88 L, final observation: 2.05 L, p = 0.045) and %FEV1 (preoperative: 57.1%, final observation: 66.2%, p = 0.001). FEV1/FVC was also significantly improved at the final observation (preoperative: 83.0%, final observation: 86.4%, p = 0.019). The peak expiratory flow (PEF) was significantly improved at the final observation (preoperative: 3.67 L/s, final observation: 4.38 L/s, p = 0.029). On the CT assessment for thoracic deformities, there were no significant changes in RA_sag or RHi. PHSr was significantly increased at the final observation compared with the preoperative period.

Conclusions: With posterior spinal fusion in combination with thoracoplasty for AIS, although the correction of deformities was limited, the pulmonary function testing demonstrated the preservation of vital capacity (VC) and improvements in the forced expiratory volume in 1 s and expiratory flow.

Keywords: Adolescent idiopathic scoliosis; Pulmonary function; Thoracic cage deformity; Thoracoplasty.