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HAND THERAPY · 2026

Hand range of motion: what does the smartphone evidence say?

Smartphone photography is a practical candidate for repeatable upper-limb range-of-motion documentation.

Camera-assisted fine-motor and hand assessment
MedMeters literature review prepared 31 October 2026. The year in the article heading refers to the original study publication, not an earlier MedMeters posting date.
31 studiesin a systematic review · findings from external research

Clinical question

Can smartphone photographs and built-in sensors support reliable upper-extremity ROM measurement?

Study design

The authors synthesized 31 studies published from 2001 to 2023, comparing smartphone-based photography or sensors with standard goniometric methods for hand and upper-limb range of motion.

What the researchers found

Eleven of twelve photography studies reported good-to-excellent reliability or validity. Evidence quality was mixed and assessment protocols differed across studies.

Why this matters for MedMeters

This supports a careful MedMeters Hand roadmap, especially calibrated photography and repeatable acquisition rather than assuming every joint can be inferred from a single uncalibrated pose estimate.

What this does not prove

Smartphone photography is not identical to automated computer vision; this review does not validate MedMeters hand-joint angles. Occlusion, perspective, sensor choice and repeatability still need separate tests.

Original peer-reviewed publication

Reliability and validity of using smartphone sensor and photography to measure hand and upper extremity joint range of motion: A systematic review
Systematic review · Journal of Hand Therapy · 2026
DOI: 10.1016/j.jht.2025.04.018

External scientific evidence summary. Not medical advice. MedMeters is a concept under development and has not been evaluated in these studies. Clinical claims, validation and regulatory status must be established separately.