2025 ISAKOS Biennial Congress ePoster
Cross-Cultural Translation and Validation of The Spanish Version of The Norwich Patellofemoral Instability (NPI) Score
Juan Pablo Martinez-Cano, MD, MSc, PhD, Cali, Valle del Cauca COLOMBIA
Alejandro Gallego, MD, Jamundí, Valle del Cauca COLOMBIA
Maria Camila Gomez Ayala, MD, MSc, Cali, Valle COLOMBIA
Giovani A. Gravini-Amador, MD, Bogota, CUNDINAMARCA COLOMBIA
Sebastián Mejía, Doctor, Bogotá D.C, Cundinamarca COLOMBIA
Fundación Valle del Lili, Cali, Valle, COLOMBIA
FDA Status Not Applicable
Summary
The Spanish version of the Norwich Patellofemoral Instability score shows high internal consistency and test-retest reliability, enabling its use in Spanish-Speaking patients with patellar instability.
ePosters will be available shortly before Congress
Abstract
Background
Patellofemoral instability is a condition characterized by dislocation or subluxation of the patella in relation to its path over the femoral trochlea. The Norwich patellofemoral instability (NPI) score is a disease-specific questionnaire for patients with this condition; however, it has not been validated for Spanish-speaking patients.
Purpose
To translate and validate the Norwich Patellofemoral Instability Score into Spanish. Evaluate its psychometric properties and correlate with the Spanish version of Kujala and the Banff Patellofemoral Instability Instrument 2.0 (BPII).
Study design: Scale translation and validation study.
Methods
The translation and validation of Norwich patellofemoral instability score into Spanish was conducted following the Consensus-based Standards for the Selection of Health Measurement Instruments guidelines. This included forward and backward translations, conciliation and a pilot study in five patients. Internal consistency was evaluated with Cronbach’s alpha and test-retest reliability with the intraclass correlation coefficient. Pearson correlation coefficients were used to calculate the correlation between the NPI Score and both Kujala and BPII scores.
Results
The study included 58 voluntary participants, predominantly female (79.7%), with a mean age of 17 years (17.4 ± 6.58). The Spanish version of NPI showed high internal consistency (Cronbach’s alpha: 0.93) and intraclass correlation coefficient (ICC: 0.88 (0.80-0.93)). Additionally, it exhibited a moderate correlation with the Kujala score (-0.57), and a high correlation with the BPII score (-0.70).
Conclusions
The Spanish version of the Norwich Patellofemoral Instability score shows high internal consistency and test-retest reliability, enabling its use in Spanish-Speaking patients with patellar instability. It showed high correlation with another disease-specific score for patellofemoral instability (BPII) and less correlation with the Kujala score, that should be predominantly used to evaluate patellofemoral pain.