Classification of Chronic Back Muscle Degeneration after Spinal Surgery and Its Relationship with Low Back Pain.
10.4184/asj.2016.10.3.516
- Author:
Seiji OHTORI
1
;
Sumihisa ORITA
;
Kazuyo YAMAUCHI
;
Yawara EGUCHI
;
Yasuchika AOKI
;
Junichi NAKAMURA
;
Tetsuhiro ISHIKAWA
;
Masayuki MIYAGI
;
Hiroto KAMODA
;
Miyako SUZUKI
;
Gou KUBOTA
;
Kazuhide INAGE
;
Takeshi SAINOH
;
Jun SATO
;
Yasuhiro SHIGA
;
Koki ABE
;
Kazuki FUJIMOTO
;
Hirohito KANAMOTO
;
Gen INOUE
;
Kazuhisa TAKAHASHI
Author Information
1. Department of Orthopaedic Surgery, Graduate School of Medicine, Chiba University, Chiba, Japan. sohtori@faculty.chiba-u.jp
- Publication Type:Original Article
- Keywords:
Lumbar;
Muscle;
Injury;
Surgery;
Pain
- MeSH:
Back Muscles*;
Back Pain;
Bone Marrow;
Classification*;
Decompression;
Humans;
Inflammation;
Low Back Pain*;
Magnetic Resonance Imaging;
Male;
Pathology;
Prevalence;
Retrospective Studies;
Spinal Stenosis
- From:Asian Spine Journal
2016;10(3):516-521
- CountryRepublic of Korea
- Language:English
-
Abstract:
STUDY DESIGN: Retrospective case series. PURPOSE: To classify back muscle degeneration using magnetic resonance imaging (MRI) and investigate its relationship with back pain after surgery. OVERVIEW OF LITERATURE: Back muscle injury and degeneration often occurs after posterior lumbar surgery, and the degeneration may be a cause of back pain. However, the relationship between back muscle degeneration and back pain remains controversial. METHODS: A total of 84 patients (average age, 65.1 years; 38 men, 46 women) with lumbar spinal stenosis underwent posterior decompression surgery alone. MRI (1.5 tesla) was evaluated before and more than a year after surgery in all patients. Muscle on MRI was classified into three categories: low intensity in T1-weighted imaging, high intensity in T2-weighted imaging (type 1), high intensity in both T1- and T2-weighted images (type 2), and low intensity in both T1- and T2-weighted imaging (type 3). The prevalence of the types and their relationship with back pain (determined on a visual analog scale) were evaluated. RESULTS: MRI revealed muscle degeneration in all patients after surgery (type 1, 6%; type 2, 82%; and type 3, 12%). Type 2 was significantly more frequent compared with types 1 and 3 (p<0.01). Low back pain was significantly improved after surgery (p<0.01). Low back pain was not associated with any MRI type of muscle degeneration after surgery (p>0.05). CONCLUSIONS: Various pathologies of back muscle degeneration after posterior lumbar surgery were revealed. Type 2 (fatty) change was most frequent, and other patients had type 3 (scar) or type 1 (inflammation or water-like) changes. According to the Modic classification of bone marrow changes, Modic type 1 change is associated with inflammation and back pain. However, no particular type of back muscle degeneration was correlated with back pain after surgery.
