Date of Paper/Work


Type of Paper/Work

Research Project

Degree Name

Doctor of Physical Therapy (DPT)


Physical Therapy

First Advisor

Cort J. Cieminski, PT, PhD, ATR


Background and Purpose:

Humeral retroversion angle (HRVA) is the angle between the proximal humeral axis and the distal humeral axis. HRVA is significantly higher in the dominant shoulder for individuals that partake in increased overhead activities. CT scans are recognized as the gold standard for measuring HRVA, although current literature is investigating the use of radiographs to measure HRVA as a more cost-effective method. The purpose of this study was to determine if there is a training effect in the ability to measure HRVA on radiographs as determined by physical therapy students.


Four second-year Doctor of Physical Therapy students measured HRVA on 35 shoulder radiographs on two separate occasions. Two of the students received training (trained group) from an experienced HRVA investigator which included written and verbal instruction on how to obtain HRVA measurements. Training also included HRVA measurement practice sessions with feedback from the experienced HRVA investigator prior to data collection. The other two students (untrained group) were provided only written instructions on how to obtain HRVA measurements. The experienced HRVA investigator served as the gold standard.


There was minimal difference in the HRVA measurements between the trained and untrained groups with the individuals in both groups demonstrating excellent intra-rater reliability. The intra-rater reliability was 0.89 and 0.87 for the trained group members and 0.89 and 0.89 for the untrained group members, respectively. In addition, the inter-rater reliability between the trained and untrained groups in comparison to the experienced clinician was also minimal. The combined inter-rater reliability for the trained group was 0.82 and untrained group was 0.80.


Novice physical therapy students can accurately measure HRVA on radiographs with written instruction and no other formal training. This demonstrates the potential to further incorporate radiographic information into clinical practice. This supports the APTA’s Vision 2020 for physical therapists to become autonomous practitioners and expand the physical therapy scope of practice.