# The Morphology and Characteristics of Hallux Rigidus

> **NIH VA I21** · VA PUGET SOUND HEALTHCARE SYSTEM · 2021 · —

## Abstract

Hallux Rigidus (HR) is the end stage of great toe osteoarthritis, which is a degenerative joint disease that effects
approximately 1 in 40 people over the age of 50. The development of arthritis in the first metatarsophalangeal
joint (MTPJ) is painful, effecting quality of life, reducing mobility and altering gait patterns. Early treatments for
pain relief include physical therapy, pharmaceuticals and modified footwear. If these treatments fail to provide
relief and the arthritis progresses, joint function is largely lost (hence rigidus for end-stage disease progression).
Concerning veterans, from 2008-2017, nationwide data from the Veterans Healthcare System yielded 87,798
patient visits for HR (1,897 in that same period for the VA Puget Sound Healthcare System), and the number of
patient visits has consistently increased year to year from 9,396 visits nationwide in 2008 to 22,180 visits in 2017.
In order to properly match veteran HR patients with proper treatment, the stage of the disease progression needs
to be properly classified.
The most common classification systems use radiographic findings. Typically, AP and lateral X-ray views are
evaluated for joint space (reduced space indicates lost cartilage), osteophytes (and indicator of arthritis), and
joint shape (as HR patients preferentially lose cartilage and gain osteophytes on the dorsal surface). Yet the
exact features evaluated, and how they are considered, is not standardized. This issue is further complicated by
some grading schemes which blend clinical findings of range of motion and pain, into the already-complex field
of radiographic features. Finally, while 2D X-rays are the standard for diagnosis, HR is a complex 3D disease
and it has been hypothesized that certain bone positional (metatarsus primus elevatus) and morphological
(articular surface shape) may be correlated with HR and possibly predispose patients to develop HR. Such
measurements can be difficult to realize on 2D X-ray, and using manual and subjective measures.
Therefore we propose to utilize existing weight-bearing CT data from control feet and obtain similar data from
fifteen HR subjects. We will use this imaging data to evaluate the Intraclass Correlation associated with some of
the more common HR classification schemes (Aim 1). This will allow us to establish reliability measures for the
existing methods of clinically grading hallux rigidus, this will aid to inform the clinical community of the reliability
of currently practiced diagnostic methods—which have a direct impact on treatment selection and patient care.
We will also use our prior experience in evaluating 3D bony anatomy to semi-automate a suite of first ray
positional (joint spacing, first metatarsal alignment, metatarsus primus elevatus) and morphological (sagittal
plane metatarsal head curvature) features, which are suspected to have a correlation to HR (Aim 2).
One of the greatest challenges associated with this work relate to developing a user-friend...

## Key facts

- **NIH application ID:** 10074158
- **Project number:** 5I21RX003331-02
- **Recipient organization:** VA PUGET SOUND HEALTHCARE SYSTEM
- **Principal Investigator:** Joseph Iaquinto
- **Activity code:** I21 (R01, R21, SBIR, etc.)
- **Funding institute:** VA
- **Fiscal year:** 2021
- **Award amount:** —
- **Award type:** 5
- **Project period:** 2020-01-01 → 2021-12-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10074158

## Citation

> US National Institutes of Health, RePORTER application 10074158, The Morphology and Characteristics of Hallux Rigidus (5I21RX003331-02). Retrieved via AI Analytics 2026-05-21 from https://api.ai-analytics.org/grant/nih/10074158. Licensed CC0.

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