Postoperative Recovery Trajectories of C-Reactive Protein, Neutrophil-to-Lymphocyte Ratio, and CRP-to-Albumin Ratio After Open Irrigation and Debridement for Native Knee Septic Arthritis: A Descriptive Single-Center Cohort Study
- 1Department of Orthopedic Surgery, Wonju Severance Christian Hospital, Yonsei University Wonju College of Medicine, 20 Ilsan-ro, Wonju 26426, Republic of Korea
- 2Department of Orthopedic Surgery, Severance Hospital, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea
- 3Department of Orthopedic Surgery, Veterans Health Service Medical Center, 53 Jinhwangdo-ro 61-gil, Gangdong-gu, Seoul 05368, Republic of Korea
Abstract
Background/Objectives: The postoperative course of the serum markers that surgeons follow after open irrigation and debridement (I&D) for native knee septic arthritis is poorly defined. We described recovery trajectories of C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), and CRP-to-albumin ratio (CAR). Methods: We retrospectively studied 98 adults treated by open I&D at one center between January 2018 and April 2026. Mixed-effects models with natural splines gave population-average geometric-mean curves for postoperative days 0–42. An exploratory group-by-time interaction compared repeat I&D patients after censoring at the first repeat operation. Results: Median age was 77.5 years; median synovial white-cell count was 54,691 cells/µL and median neutrophil percentage 93%; and cultures were positive in 39.8% of patients. Twelve patients (12.2%) underwent repeat I&D, eight during the index admission and four after readmission, and three (3.1%) underwent salvage surgery (minimum estimates). Fitted CRP fell below 5 mg/dL by day 8 and 3 mg/dL by day 13, and CAR fell below 1.0 by day 12; fitted NLR reached 3 by day 22, but its confidence band did not exclude non-attainment within 42 days. Milestones were 1 to 13 days later in culture-confirmed subgroups. In exploratory, underpowered analyses censored at reoperation, neither preoperative levels nor decline slopes clearly distinguished repeat I&D patients (CRP interaction p = 0.78); an uncensored model’s nominal CRP association largely disappeared. Conclusions: CRP, NLR, and CAR showed distinct population-average postoperative trajectories after open I&D. These descriptive curves may assist expectation-setting and study design but should not be used as stand-alone indicators of infection control or joint outcome. Multicenter prospective studies with standardized sampling and functional endpoints are needed.
Related
- Preoperative neutrophil-lymphocyte axis and postoperative mortality: an INSPIRE analysis
- Association of early neutrophil-to-lymphocyte ratio trajectories with cardiac recovery and live ICU discharge in patients with sepsis-induced cardiomyopathy: a retrospective cohort study.
- Nonlinear associations of the neutrophil-to-lymphocyte ratio and derived neutrophil-to-lymphocyte ratio with asthma–COPD overlap prevalence: a cross-sectional study
- Neutrophil-to-Lymphocyte Ratio Identifies a Pulmonary Vascular High-Risk Phenotype in Heart Failure with Preserved Ejection Fraction
- Prognostic value of the neutrophil-to-lymphocyte ratio in patients with colorectal cancer undergoing chemotherapy: a systematic review and meta-analysis
BibTeX
@article{lee2026postoperative,
title = {{Postoperative Recovery Trajectories of C-Reactive Protein, Neutrophil-to-Lymphocyte Ratio, and CRP-to-Albumin Ratio After Open Irrigation and Debridement for Native Knee Septic Arthritis: A Descriptive Single-Center Cohort Study}},
author = {Jaemin Lee and YoungHwan Jang and Philsun Park and Jaehyuk Lee and Doo Sup Kim},
journal = {Journal of Clinical Medicine},
year = {2026},
month = oct,
doi = {10.3390/jcm15218311},
url = {https://www.mdpi.com/2077-0383/15/21/8311},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Postoperative Recovery Trajectories of C-Reactive Protein, Neutrophil-to-Lymphocyte Ratio, and CRP-to-Albumin Ratio After Open Irrigation and Debridement for Native Knee Septic Arthritis: A Descriptive Single-Center Cohort Study
AU - Jaemin Lee
AU - YoungHwan Jang
AU - Philsun Park
AU - Jaehyuk Lee
AU - Doo Sup Kim
PY - 2026
DA - 2026/10/25
JO - Journal of Clinical Medicine
DO - 10.3390/jcm15218311
UR - https://www.mdpi.com/2077-0383/15/21/8311
AB - Background/Objectives: The postoperative course of the serum markers that surgeons follow after open irrigation and debridement (I&D) for native knee septic arthritis is poorly defined. We described recovery trajectories of C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), and CRP-to-albumin ratio (CAR). Methods: We retrospectively studied 98 adults treated by open I&D at one center between January 2018 and April 2026. Mixed-effects models with natural splines gave population-average geometric-mean curves for postoperative days 0–42. An exploratory group-by-time interaction compared repeat I&D patients after censoring at the first repeat operation. Results: Median age was 77.5 years; median synovial white-cell count was 54,691 cells/µL and median neutrophil percentage 93%; and cultures were positive in 39.8% of patients. Twelve patients (12.2%) underwent repeat I&D, eight during the index admission and four after readmission, and three (3.1%) underwent salvage surgery (minimum estimates). Fitted CRP fell below 5 mg/dL by day 8 and 3 mg/dL by day 13, and CAR fell below 1.0 by day 12; fitted NLR reached 3 by day 22, but its confidence band did not exclude non-attainment within 42 days. Milestones were 1 to 13 days later in culture-confirmed subgroups. In exploratory, underpowered analyses censored at reoperation, neither preoperative levels nor decline slopes clearly distinguished repeat I&D patients (CRP interaction p = 0.78); an uncensored model’s nominal CRP association largely disappeared. Conclusions: CRP, NLR, and CAR showed distinct population-average postoperative trajectories after open I&D. These descriptive curves may assist expectation-setting and study design but should not be used as stand-alone indicators of infection control or joint outcome. Multicenter prospective studies with standardized sampling and functional endpoints are needed.
SN - 2077-0383
ER -