Relationship of Periostin and ODI, EQ-5D

The intervertebral disc degeneration (IVDD) is a widely recognized musculoskeletal disorder that impose a substantial socioeconomic burden and respresents one of the most important causes of low back pain. IVDD can result from a variety of factors, including aging, obesity, genetic predispositioin, degeneration of of the multifidus and psoas muscles, osteoporosis, inflammation, and oxidative stress. The IVD consists of a central gelatinous nucleus pulposus (NP), an outer annulus fibrosus (AF), and superior and inferior cartilaginous endplates. The NP and AF produce a water-rich extracellular matrix (ECM), which is essential for normal trunk function. Dysfunction of the NP and AF, together with excessive metabolic activity of the enplates triggered by various intrinsic and extrinsic stimuli, leads to endplate degeneration and calcification, and ultimately to IVDD. In addition to aging and mechanical overload, increased oxidative stress and pro-inflammatrory cytokine secretion further accelerate the progression of IVDD. Periostin is an ECM protein which is associated with mechanical stress, inflammation, and aging, and is known to be closely involved in the development and progression of IVDD. Periostin binds to ECM molecule within the IVD and participates in its maintenance and repair; however, excessive ECM turn over drives IVD degeneration and its progression. Periostin influences IVD degeneration through mechanical stress and inflammatory pathways, and serum periostin levels are elevated in patients with severe IVD degeneration. A recent study demonstrated strong corrrelation between serum periostin concentration and the Pfirmann grading system. The Oswestry disability index is a validated scale that measures functional disability in patients with spinal pain, and the EQ-5D is a breif questionnaire used to assess health related quality of life. Because serum periostin levels reflect the severity of IVDD, periostin may also influence patient's functional disability and quality of life. However, whether serum periostin concentration correlates with functional disability and quality of life has not yet been studied.