Improved diagnostic accuracy with the classification tree method for diagnosing low-grade periprosthetic joint

Related Experiment Video

Updated: Jan 24, 2026

Synovial Fluid Analysis to Identify Osteoarthritis
07:51

Synovial Fluid Analysis to Identify Osteoarthritis

Published on: October 20, 2022

6.2K

Max Ettinger1, Peter Savov2, Tilman Calliess2

  • 1Department of Orthopaedic Surgery, Hannover Medical School, Anna-von-Borries-Straße 1-7, 30625, Hannover, Germany. max@ettinger.info.

International Orthopaedics
|May 26, 2019
PubMed
Abstract

Insights

Diagnosing low-grade periprosthetic joint infections (PJIs) is difficult. A combination of alpha defensin and C-reactive protein (CRP) in synovial fluid shows promise for distinguishing infection from aseptic loosening before surgery.

Area of Science:

  • Orthopedic Surgery
  • Biomarker Research
  • Infectious Diseases

Background:

  • Diagnosing low-grade periprosthetic joint infections (PJIs) is challenging due to non-specific symptoms and unreliable biomarkers.
  • Misdiagnosis can lead to revision surgery failure or unnecessary procedures and antibiotic use.
  • Accurate preoperative differentiation between aseptic loosening and low-grade PJI is crucial.

Purpose of the Study:

  • To evaluate the efficacy of synovial fluid biomarkers in distinguishing between aseptic prosthesis loosening and low-grade PJI.
  • To identify the most accurate combination of biomarkers for preoperative diagnosis.

Main Methods:

  • Prospective collection of synovial fluid from patients undergoing revision arthroplasty.
  • Quantitative measurement of alpha defensin, C-reactive protein (CRP), IL-6, IL-10, and lipopolysaccharide binding protein (LBP).
  • Utilized classification tree method to analyze biomarker performance.

Main Results:

  • The combination of alpha defensin and CRP demonstrated the highest accuracy in differentiating aseptic loosening from low-grade PJI.
  • A threshold of CRP > 2.0 mg/L and alpha defensin > 90,000 pg/mL correctly identified 9 out of 11 patients with low-grade infection.

Conclusions:

  • Alpha defensin combined with CRP is a highly effective biomarker panel for preoperative diagnosis.
  • This biomarker combination aids in differentiating aseptic loosening from low-grade PJI, improving surgical planning.
Keywords:
High-gradeJoint infectionLow-gradeSeptic joint failure

More Related Videos

Author Spotlight: Advancing Research on Candida albicans Biofilm-Associated Prosthetic Joint Infections04:37

Author Spotlight: Advancing Research on Candida albicans Biofilm-Associated Prosthetic Joint Infections

Published on: February 2, 2024

1.3K
Anterior Cruciate Ligament Transection and Synovial Fluid Lavage in a Rodent Model to Study Joint Inflammation and Posttraumatic Osteoarthritis06:28

Anterior Cruciate Ligament Transection and Synovial Fluid Lavage in a Rodent Model to Study Joint Inflammation and Posttraumatic Osteoarthritis

Published on: September 2, 2025

1.2K

Related Concept Videos

Structural Joints: Synovial Joints01:16

Structural Joints: Synovial Joints

Synovial joints are the most common type of joint in the body. A key structural characteristic for a synovial joint is the presence of a joint cavity. This fluid-filled space is where the articulating surfaces of the bones contact each other. Also, unlike fibrous or cartilaginous joints, the articulating bone surfaces at a synovial joint are not directly connected to each other with fibrous connective tissue or cartilage. This gives the bones of a synovial joint the ability to move smoothly...
6.5K
Improving Translational Accuracy02:07

Improving Translational Accuracy

Base complementarity between the three base pairs of mRNA codon and the tRNA anticodon is not a failsafe mechanism. Inaccuracies can range from a single mismatch to no correct base pairing at all. The free energy difference between the correct and nearly correct base pairs can be as small as 3 kcal/ mol. With complementarity being the only proofreading step, the estimated error frequency would be one wrong amino acid in every 100 amino acids incorporated. However, error frequencies observed in...
14.1K
Improving Translational Accuracy02:07

Improving Translational Accuracy

3.6K
Development of the Limb Synovial Joints01:07

Development of the Limb Synovial Joints

Joints form during embryonic development in conjunction with the formation and growth of the associated bones. The embryonic tissue that gives rise to all bones, cartilage, and connective tissues of the body is called mesenchyme.
The mesenchymal stem cells differentiate into chondrocytes that form the hyaline cartilage, and later the cartilaginous model of the bone. This model further transforms into a bone. This process is known as endochondral ossification.
During development, the limbs...
2.2K
Structural Classification of Joints01:20

Structural Classification of Joints

Joints, also known as articulations, are classified based on their structural characteristics, i.e., based on whether the articulating surfaces of the adjacent bones are directly connected by fibrous connective tissue or cartilage, or whether the articulating surfaces contact each other within a fluid-filled joint cavity. These differences serve to divide the joints of the body into three structural classifications.
A fibrous joint is where the adjacent bones are united by fibrous connective...
7.1K
Functional Classification of Joints01:09

Functional Classification of Joints

Functional Classification of Joints
The functional classification of joints is determined by the amount of mobility between the adjacent bones. Joints are functionally classified as a synarthrosis or immobile joint, an amphiarthrosis or slightly moveable joint, or as a diarthrosis, a freely moveable joint. Fibrous and cartilaginous joints can be functionally classified as either synarthroses  or amphiarthroses, whereas all synovial joints are classified as diarthroses.
Synarthrosis
An...
6.6K