# Assessing the Reliability of Hip Physical Examination via Telemedicine: Intra- and Inter-observer Analysis in Osteoarthritis, Total Hip Arthroplasty, and Normal Hips

## TL;DR

This study shows that telemedicine can reliably assess hip function for osteoarthritis, hip replacements, and normal hips, especially when using a standardized instructional video.

## Contribution

The study introduces the use of a standardized instructional video to improve telemedicine reliability for hip exams, a novel approach in this field.

## Key findings

- Hip range of motion and TUG test showed excellent reliability via telemedicine (ICC > 0.99).
- Muscle trophism and Trendelenburg test had low reliability due to technical limitations like lighting and camera positioning.
- A pre-recorded instructional video improved assessment consistency compared to prior studies.

## Abstract

Background

Telemedicine is an emerging tool in orthopedic care, offering remote assessments for patients with limited mobility or in underserved areas. However, its use for hip joint exams remains understudied. This study addresses that gap by evaluating intra- and inter-observer reliability of telemedicine-based hip exams in osteoarthritis, total hip arthroplasty, and asymptomatic cases. We analyzed 100 hips from 50 patients, treating each hip independently. Notably, this is the first study to incorporate a standardized instructional video to enhance examiner consistency.

Objective

This study aimed to evaluate the reliability of hip joint physical examinations performed via telemedicine compared to traditional in-person evaluations in individuals with hip osteoarthritis, total hip arthroplasty (THA), and normal hips. We hypothesized that telemedicine-based assessments would demonstrate substantial intra- and inter-observer reliability, supporting their potential integration into orthopedic clinical practice. The parameters assessed included lower limb muscle trophism, claudicating gait, the Trendelenburg test, hip range of motion (flexion, extension, abduction, adduction, internal and external rotation), and the Timed Up and Go (TUG) test.

Methods

This was a cross-sectional, analytical, and comparative study involving 100 hips from 50 patients. Each patient contributed with both hips, which were evaluated individually. Participants were categorized into three groups based on the clinical condition of each hip: hip osteoarthritis (n=33), THA (n=33), and normal hips (n=34). Thus, a single patient could have hips classified into different groups. Each hip was treated as an independent observational unit to enable a detailed biomechanical and functional analysis across the groups. However, for the Timed Up and Go (TUG) test, since it is a global functional assessment, the evaluation was performed per patient rather than per hip. Unlike the other tests, which focused on hip-specific mobility, the TUG test reflects overall patient function. Therefore, the sample size for this test was 50.

Results

Hip flexion, extension, abduction, adduction, internal and external rotation, and the Timed Up and Go (TUG) test showed good to excellent reliability (kappa > 0.6; Intraclass Correlation Coefficient (ICC) > 0.99). Claudicating gait demonstrated moderate to very good agreement, varying by clinical group. In contrast, muscle trophism and the Trendelenburg test showed low reliability (kappa < 0.6), possibly due to inadequate lighting, camera positioning, or difficulty distinguishing subtle visual cues. Notably, the use of a standardized instructional video prior to the virtual exam contributed to higher reliability when compared to previously published studies. No adverse events or complications occurred in patients with total hip arthroplasty or osteoarthritis during the remote assessments, reinforcing the safety of the method.

Conclusion

Telemedicine proved to be a reliable and safe method for assessing most functional aspects of the hip, particularly joint range of motion and gait. The use of a pre-recorded instructional video enhanced the consistency of virtual assessments, supporting its integration into routine orthopedic practice, especially when in-person evaluation is not feasible.