Factors Affecting the Elevation of Inflammatory Markers Before Primary Total Hip Arthroplasty.

Background: Abnormal inflammatory marker levels are often detected in patients who have multiple comorbidities before primary total hip arthroplasty (THA) without a specific infection. This study aimed to examine the prevalence of the elevation of inflammatory markers, distribution of inflammatory markers, and factors affecting the elevation of inflammatory marker levels before primary THA. Methods: A retrospective review of 511 THA cases from the outpatient clinic of a single institution was conducted. Patients were divided into 2 groups with normal (group A: n = 432) vs abnormal (group B: n = 79) C-reactive protein (CRP) values using threshold for the upper limit of normal of 0.5 mg/dL. Preoperative diagnoses and underlying diseases of the patients were reviewed. Underlying diseases and medical history included autoimmune inflammatory disease; diabetes mellitus; chronic kidney disease; histories of cancer, organ transplantation, and contralateral hip arthroplasty; and preoperative urinalysis. The distribution of inflammatory markers, prevalence of preoperative diagnosis, and underlying diseases were compared. Results: The prevalence of elevated CRP levels was 15.5%. Mean values of all inflammatory markers were significantly lower in group A. The risk of elevated CRP was higher with osteonecrosis of the femoral head (ONFH) and subchondral insufficiency fracture of the femoral head (SIFFH) compared to hip arthritis (ONFH: odds ratio = 3.03; SIFFH: odds ratio = 4.85). The prevalence of autoimmune inflammatory disease was higher in group A than in group B. No difference in the prevalence of other underlying diseases was observed between the groups. Conclusions: Elevated inflammatory markers are commonly observed before primary THA. Although the distribution of inflammatory markers was different, only CRP level was different based on normal range. Regarding preoperative diagnosis, ONFH and SIFFH significantly influenced the elevation of inflammatory marker levels compared to hip arthritis. Regarding underlying diseases, autoimmune inflammatory disease was the only significant factor affecting the elevation of inflammatory markers.