Cross-Cultural Translation and Validation of The Spanish Version of The Norwich Patellofemoral Instability (NPI) Score

Cross-Cultural Translation and Validation of The Spanish Version of The Norwich Patellofemoral Instability (NPI) Score

Juan Pablo Martinez-Cano, MD, MSc, PhD, COLOMBIA Alejandro Gallego, MD, COLOMBIA Maria Camila Gomez Ayala, MD, MSc, COLOMBIA Giovani A. Gravini-Amador, MD, COLOMBIA Sebastián Mejía, MD, COLOMBIA

Fundación Valle del Lili, Cali, Valle, COLOMBIA


2025 Congress   ePoster Presentation   2025 Congress   Not yet rated

 

Anatomic Location

Diagnosis / Condition

Sports Medicine


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.


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.