Diagnosis and Characters of Non-Specific Low Back Pain in Japan: The Yamaguchi Low Back Pain Study

Abstract

Study design: Cross sectional data from the Yamaguchi low back pain study conducted in Yamaguchi prefecture, Japan, was used for this analysis.

Methods: A total of 320 patients were recruited from walk-in orthopedic clinics in Yamaguchi Prefecture, Japan. Patients visited the clinics primarily for low back pain (LBP) and sought treatment between April and May 2015. A self-questionnaire was completed by patients, while radiographic testing and neurological and physical examination was performed by the orthopedist in each hospital. The cause and characters of LBP was determined following examination of the data, regional anesthesia and block injection.

Results: 'Specific LBP' was diagnosed in 250 (78%) patients and non-diagnosable, 'non-specific LBP' in 70 (22%) patients. The VAS scores of patients were: LBP, 5.8±0.18; leg pain, 2.9±0.18 and the intensity of leg numbness was 1.9±0.16. Item scores for SF-8 were: general health, 46.6±0.40; physical function, 43.5±0.51; physical limitations, 42.8±0.53; body pain, 42.1±0.52; vitality, 48.4±0.37; social function, 46.9±0.53; emotional problems, 48.9±0.43; mental health, 46.9±0.43.

Conclusions: The incidence of non-specific LBP in Japan was lower than previous reports from western countries, presumably because of variation in the diagnosis of LBP between different health care systems. In Japan, 78% of cases were classified as 'specific LBP' by orthopedists. Identification of the definitive cause of LBP should help to improve the quality of LBP treatment.

Fig 1. Common tools used for radiographic, neurological and physical examination.

The orthopedist recorded all examination data for each LBP patient.

Fig 2. Summary of the Differential Diagnosis of LBP.

Total number of LBP patients is 320.

Fig 3. How to make a definitive diagnosis in each LBP.

Specific physical findings for assisting diagnosis.

Fig 4. The background characteristics of patients in this study were assessed by JOABPEQ (a), VAS (b), and SF-8 (c).

Fig 5. Sensitivity and specificity of the LBP test for Fascial lumbago.

Fig 6. Sensitivity and specificity of the LBP test for Facet joint syndrome.

Fig 7. Sensitivity and specificity of the LBP test for Discogenic lumbago.