First trial to test big-toe fusion against watchful waiting favours surgery

Hallux rigidus — osteoarthritis of the joint at the base of the big toe — is common, painful and limits walking [s1]. Surgery to fuse the joint has been done for decades. What has never been done, remarkably, is a randomised trial comparing that operation with simply leaving the disease to run its natural course [s1]. Almost every surgical procedure in wide use rests on a comparison with a conservative alternative; for this one, that comparison did not exist until now.

A single-centre trial from Finland, published in Annals of Internal Medicine, fills the gap — and lands firmly on the side of surgery [s1].

What the trial did

This was a single-centre, parallel-group, randomised, controlled superiority trial with 12-month follow-up, run at the orthopaedic department of a tertiary care hospital in Finland [s1]. Eligible patients were adults aged 40 years or older with radiographically confirmed hallux rigidus (Coughlin- Shurnas grade I to III), symptoms lasting more than a year, and a walking-pain score of 4 or higher on a 0-to-10 numerical rating scale [s1]. People with type 1 diabetes, rheumatoid arthritis, or a hallux valgus angle greater than 15 degrees were excluded [s1].

Between November 2021 and June 2024, 90 patients were randomly assigned in a 1:1 ratio — 45 to surgery and 45 to watchful waiting, with a mean age of 58.1 years [s1]. The eligibility rules were deliberately tight: symptoms had to have persisted for more than a year and to be at least moderate (a walking-pain score of 4 or higher), so the trial was testing surgery in people whose disease had already declared itself rather than in mild or incidental cases [s1]. The operation was first metatarsophalangeal joint arthrodesis, a fusion using a lag screw and dorsal plating [s1]. The primary outcome was walking-related pain on the 0-to-10 scale at 12 months, and the researchers set the minimal clinically important difference in advance at 1.7 points [s1]. The trial is registered as NCT04590313 [s2].

What happened

The result was large and clear. At 12 months, the mean walking-related pain was 1.3 in the arthrodesis group and 5.7 in the watchful waiting group [s1]. That is an adjusted mean difference of -5.0 points (95% CI -6.1 to -3.9) in favour of surgery [s1].

Two things make that number persuasive. First, its size: a 5.0-point gap on a 10-point scale is not a marginal effect [s1]. Second, its comparison to the bar the researchers set beforehand — the whole confidence interval, from -6.1 to -3.9, lies well beyond the 1.7-point threshold they had defined as the smallest difference that matters to patients [s1]. Follow-up was near-complete: 89 of the 90 participants completed the 12-month assessment [s1].

What the trial does and does not establish

The trial answers a question that had genuinely never been tested: fusing the joint beats waiting, for walking pain, at one year [s1]. That is a real addition to the evidence, because "everyone knows surgery works" is not the same as having randomised proof, and plenty of long-standing operations have wilted when finally tested against a conservative arm.

But there are limits worth stating plainly. This was a single-centre study, which the authors flag as a limitation — results from one Finnish hospital may not transfer everywhere [s1]. The follow-up runs to 12 months, so it speaks to pain at one year, not to durability over the many years a fused joint has to last, nor to the trade-offs of fusion, which permanently eliminates motion at that joint [s1]. And watchful waiting is not the only non-surgical option; the trial did not pit fusion against, say, a stiff-soled shoe or an injection [s1].

The comparison here is surgery versus the natural course of the disease [s1] — informative precisely because it is the baseline every other option should also be measured against.

Who funded it

The trial's primary funding came from the Suomen Lääketieteen Säätiö (the Finnish Medical Foundation), an academic funder, rather than from a device maker or other commercial sponsor [s1]. For a study evaluating a specific piece of surgical hardware, that independence is worth noting.

What to watch

The open questions are durability and comparators. Longer follow-up would show whether the one-year pain advantage holds, and how the fused joints fare over time [s1]. And because fusion removes movement permanently, future trials comparing it with joint-preserving surgery or structured conservative care would tell patients not just whether surgery helps, but which kind [s1].

This article describes trial results. It is not medical advice, and nothing here should be used to decide for or against an operation.

Sources

• Surgery Versus Watchful Waiting for First Metatarsophalangeal Joint Osteoarthritis, Annals of Internal Medicine, 10 August 2026
• Treatment of Hallux Rigidus (HARD) trial registration (NCT04590313), ClinicalTrials.gov, first posted 19 October 2020