Reference intervals and sources of variation of pressure pain threshold for quantitative sensory testing in a Japanese population.

Quantitative sensory testing (QST) is useful when analysing musculoskeletal pain disorders. A handheld algometer is most commonly used for pressure pain threshold (PPT) tests. However, reference intervals for PPTs are not elucidated. We assessed reference intervals of PPTs for QST in 158 healthy adult Japanese with no history of musculoskeletal or neurological problems. A handheld algometer was used to record PPT at five different assessment sites on the body: lumbar paravertebral muscle, musculus gluteus maximus, quadriceps, tibialis anterior muscle, and anterior talofibular ligament. Multiple regression analysis was performed to explore sources of variation of PPT according to sex, age, body mass index, UCLA Activity Level Rating, and Tegner Activity Score. Reference intervals were determined parametrically by Gaussian transformation of PPT values using the two-parameter Box-Cox formula. Results of multiple regression analysis revealed that age was significantly associated with PPT of lumbar paravertebral muscle and musculus gluteus maximus. In females, body mass index showed significant positive correlation with PPT of anterior talofibular ligament, and UCLA Activity Level Rating also showed significant positive association with tibialis anterior muscle and anterior talofibular ligament. Site-specific reference intervals of PPTs for Japanese are of practical relevance in fields of pain research using a handheld algometer.

Effects of spinal segmental flexion and extension exercises on spinal flexibility.

BACKGROUND: We considered spinal segmental movement exercise that voluntarily control local muscles as a convenient treatment to correct the trunk muscle recruitment pattern in individuals with global muscle overactivity. The purpose of this study was to verify the effects of segmental flexion and extension movements of the spine and overall flexion and extension movements of the spinal column on the flexibility of the spinal column among healthy university students who had completed a day of lectures and had a certain load on their lower back as a preliminary step to applying the exercise to low back pain patients with a broken trunk muscle recruitment pattern. METHODS: The subjects performed trunk flexion/extension exercises that required segmental control of the spine (segmental movement) and trunk flexion/extension exercises that do not require segmental control of the spine (total movement) in the chair position. As an evaluation task, finger floor distance (FFD) and muscle tension of the hamstrings were evaluated before and after exercise intervention. RESULTS: There was no significant difference in the FFD value and the passive pressure before the intervention between the two exercises. FFD decreased significantly after the intervention compared to that before, and passive pressure did not change in both motor tasks. The FFD change amount of segmental movement was significantly larger than that of total movement. (P < 0.01). CONCLUSIONS: It has been suggested that segmental spinal movements improve spinal mobility and may reduce global muscle tension.

Current Concept of Quantitative Sensory Testing and Pressure Pain Threshold in Neck/Shoulder and Low Back Pain.

In recent years, several published articles have shown that quantitative sensory testing (QST) and pressure pain threshold (PPT) are useful in the analysis of neck/shoulder and low back pain. A valid reference for normal PPT values might be helpful for the clinical diagnosis of abnormal tenderness or muscle pain. However, there have been no reliable references for PPT values of neck/shoulder and back pain because the data vary depending on the devices used, the measurement units, and the area examined. In this article, we review previously published PPT articles on neck/shoulder and low back pain, discuss the measurement properties of PPT, and summarize the current data on PPT values in patients with chronic pain and healthy volunteers. We also reveal previous issues related to PPT evaluation and discuss the future of PPT assessment for widespread use in general clinics. We outline QST and PPT measurements and what kinds of perceptions can be quantified with the PPT. Ninety-seven articles were selected in the present review, in which we focused on the normative values and abnormal values in volunteers/patients with neck/shoulder and low back pain. We conducted our search of articles using PubMed and Medline, a medical database. We used a combination of "Pressure pain threshold" and "Neck shoulder pain" or "Back pain" as search terms and searched articles from 1 January 2000 to 1 June 2022. From the data extracted, we revealed the PPT values in healthy control subjects and patients with neck/shoulder and low back pain. This database could serve as a benchmark for future research with pressure algometers for the wide use of PPT assessment in clinics.