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Updated: Oct 18, 2026

The Transition to an Anterior-Based Muscle Sparing Approach Improves Early Postoperative Function but is Associated with a Learning Curve
Published on: September 7, 2022
Preoperative pain and achievement of the minimal clinically important difference for physical function one year after
Rubén Gajardo-Burgos1,2, Ricardo Arteaga San Martín3, Jorge Fuentes4
1Instituto de Ciencias del Movimiento y la Ocupación Humana, Universidad Austral de Chile, Valdivia, Chile. ruben.gajardo@uach.cl.
Purpose:
To examine the association between preoperative social, clinical, and biological variables and the achievement of the minimal clinically important difference (MCID) on the WOMAC-function subscale one year post total hip arthroplasty (THA).
Methods:
In this prospective cohort study, 85 patients (aged ≥ 65) completed baseline preoperative assessment, and 53 completed the 12-month follow-up (32 lost to follow-up; 66.0% achieved MCID). The outcome was achieving WOMAC-function MCID (≥ 26.54 points). Multivariable logistic regression adjusted for baseline pain, age, sex, and BMI were performed. ROC curves evaluated discriminative capacity.
Results:
An exploratory ROC analysis identified a baseline pain threshold of 6.5 on the Numerical Rating Scale yielded an AUC of 0.740 (70% sensitivity, 77% specificity).
Conclusions:
Preoperative pain intensity independently associated with clinically meaningful functional improvement post-THA. An exploratory pain threshold of 6.5 on the NRS may provide an exploratory benchmark for future risk stratification.