Trigger toe is a condition in which a toe catches, locks, or snaps painfully during movement, much like a stuck door hinge that suddenly gives way. The medical term is hallux saltans when it affects the big toe, and the problem almost always traces back to the tendon that flexes the toe getting pinched as it passes through a narrow tunnel of tissue. While it shares a name and a mechanism with the far more common trigger finger, trigger toe has its own set of causes, affects different populations, and sometimes requires a different treatment approach.
How the Tendon Gets Stuck
The flexor hallucis longus (FHL) tendon runs from the calf muscle all the way down to the tip of the big toe. Along the way it passes through several tight channels lined with fibrous tissue, and these channels act like pulleys to keep the tendon tracking close to the bone. The most common site of trouble is a fibro-osseous tunnel that sits just below a bony shelf on the inner side of the ankle called the sustentaculum tali.1The Journal of Foot and Ankle Surgery. Hallux Saltans due to Flexor Hallucis Longus Entrapment at a Previously Unreported Site in an Unskilled Manual Laborer: A Case Report When the pulley at that spot thickens or the tendon itself swells, the tendon can no longer glide smoothly. It catches on the way through, builds up tension, and then releases with a palpable snap.
The thickening is typically fibrous tissue that builds up around the pulley structure over time.2PubMed Central. Bilateral hallux Saltans, a Rare Finding: Diagnosis and Arthroscopic Treatment in a Young Ballet Dancer: Report of a Case Think of it as scar-like tissue slowly narrowing the channel until the tendon no longer fits through without friction. Inflammation of the tendon sheath (tenosynovitis) can contribute as well, adding swelling inside an already tight space. Once the cycle of catching and inflammation begins, it tends to worsen rather than resolve on its own, because each snap irritates the tissue further.
Who Is Most at Risk
Trigger toe has a well-established link to activities that demand extreme, repeated pointing of the foot. Classical ballet dancers are the most frequently reported group in the medical literature, because dancing en pointe forces the ankle and big toe into maximum downward flexion under the dancer’s full body weight.3PubMed. Trigger toe in classical-ballet dancers That position loads the FHL tendon heavily and drives it back and forth through the pulley with every relevé and jump. Over months and years of training, the tendon and its surrounding sheath can thicken from the repetitive stress.
Research using ultrasound has shown that dancers diagnosed with FHL tendinopathy have measurably thicker tendons compared to both healthy dancers and non-dancers.4PubMed Central. Flexor hallucis longus tendon morphology in dancers clinically diagnosed with tendinopathy Interestingly, healthy dancers without symptoms did not have significantly thicker tendons than people who never danced at all, which suggests the thickening is tied to injury or overuse rather than simply being a normal adaptation to dance training.
Dancers are not the only ones affected, though. Case reports describe trigger toe in manual laborers whose work involves sustained gripping or pushing with the foot, and in recreational athletes who run or hike on uneven terrain. The condition can also appear without any obvious overuse history, particularly when the person’s anatomy is predisposed. Some people are born with an FHL muscle belly that extends unusually far down toward the ankle. This “low-lying” muscle belly sits closer to the pulley at the sustentaculum tali and can crowd the tunnel even without significant thickening of the tendon itself.5PubMed Central. Do Patients With Functional Hallux Limitus Have a Low-Lying or Bulky FHL Muscle Belly? In one study, patients with impaired big-toe motion had significantly less clearance between the bottom of the muscle belly and the pulley than those with normal toe function. A low-lying muscle belly has also been identified as a cause of posterior ankle impingement, where the bulky muscle gets pinched between the ankle bones during pointing.6PubMed. Low-lying flexor hallucis longus muscle causing posterior ankle impingement: Ultrasound findings and case report
The Diabetes Connection
Trigger conditions in the hand are famously associated with diabetes, and there is growing evidence that the same systemic process affects tendons throughout the body, including the foot. Diabetes promotes changes in connective tissue through a process involving advanced glycation end-products, which are sugar-modified proteins that accumulate in tendons and their sheaths over time. Research on the flexor tendon synovium in patients with diabetes has found elevated expression of the receptor for these glycation end-products in the tissue lining the tendon tunnel, and that expression was independently associated with the development of compressive tendon conditions even after accounting for age and body weight.7PubMed. Is RAGE Expression in Flexor Tendon Synovium Associated With Carpal Tunnel Syndrome in Patients With Diabetes While that particular study focused on the wrist, the underlying biology applies to any flexor tendon pulley system, including those in the toes. If you have diabetes and notice a catching or locking sensation in a toe, it is worth mentioning to your doctor rather than assuming it is just stiffness.
Recognizing the Symptoms
The hallmark symptom is a toe that catches during bending and then suddenly releases with a snap. In mild cases you might feel a subtle click at the base of the big toe or behind the inner ankle when you push off during walking. As the condition progresses, the catching becomes more pronounced and painful. Some people describe it as the toe “getting stuck” in a bent position for a moment before popping straight, and the snap can sometimes be heard as well as felt.
Pain tends to concentrate in one of two places. The first is behind and below the inner ankle bone, right where the FHL tendon passes through the sustentaculum tali tunnel. The second is under the ball of the foot near the base of the big toe. Swelling in the area is common but not always visible from the outside, since the inflamed structures sit deep beneath the skin. Morning stiffness is a frequent complaint as well, because the tendon sheath swells overnight and the first few steps can be especially uncomfortable until the tissue loosens up.
In more advanced cases the toe can lock completely in a flexed position, requiring you to physically straighten it with your hand. This is the same “locked trigger” phenomenon seen in severe trigger finger and represents a stage where conservative treatment alone becomes less likely to resolve the problem.
When the Smaller Toes Are Involved
Most of the medical literature on trigger toe focuses on the big toe, but the lesser toes can trigger as well. The smaller toes have their own pulley system that is structurally very similar to the one found in the fingers. Cadaver studies have identified a series of fibrous bands running from the base of each toe out to the tip, and these pulleys can thicken and entrap the flexor tendons just as the A1 pulley does in a trigger finger.8PubMed. Triggering of the lesser toes at a previously undescribed distal pulley system Patients with lesser-toe triggering often present with pain under the ball of the foot (metatarsalgia) along with the catching sensation, which can be mistaken for a Morton’s neuroma or a plantar plate tear if the examiner is not specifically looking for triggering.
Lesser-toe triggering is rare enough that it can go undiagnosed for months. If you have pain in the ball of your foot and notice a toe that clicks or locks during movement, pointing that specific symptom out to your clinician can speed up the correct diagnosis considerably.
How Trigger Toe Is Diagnosed
Diagnosis usually starts with a physical exam. Your doctor or physiotherapist will ask you to flex and extend the toe while they feel for the catch. In many cases the snap is obvious enough that no imaging is needed. When the diagnosis is uncertain, or when surgery is being planned, imaging helps clarify what is going on inside the tendon tunnel.
Both MRI and ultrasound can assess plantar tendon problems, including tendon thickening, inflammation of the sheath, and structural changes at the pulley.9PubMed. Plantar tendons of the foot: MR imaging and US Ultrasound has a particular advantage for trigger toe because it is a dynamic exam: the sonographer can watch the tendon in real time as you move the toe and directly visualize the moment it catches. High-resolution ultrasound can also measure pulley thickness with precision. In confirmed cases of trigger toe, the A1 pulley of the big toe has been found to be roughly double the thickness of the same pulley on the unaffected side.10PubMed Central. High-resolution ultrasound of the annular pulley system in the toes: sonographic anatomy and pathological cases That kind of side-to-side comparison is quick and convincing, and it can also pick up other problems like partial pulley tears that might change the treatment plan.
Conditions That Look Similar
Several other problems in the back of the ankle and underside of the foot can mimic trigger toe, and getting the diagnosis right matters because the treatments differ. One of the most common mimics is os trigonum syndrome, where a small extra bone at the back of the ankle gets pinched during downward pointing of the foot. The os trigonum sits right next to the FHL tendon tunnel, and the two conditions often coexist. When they do, the combination is considered a common cause of posterior ankle impingement, especially in dancers and athletes who repeatedly point their feet.11PubMed Central. Disorders of the Flexor Hallucis Longus and Os Trigonum
Other conditions on the differential include FHL tendinopathy without triggering (pain and thickening but no catching), plantar plate injuries of the lesser toes, sesamoiditis under the big toe, and tarsal tunnel syndrome where the tibial nerve is compressed on the inner ankle. An experienced examiner can usually distinguish these clinically, but imaging helps in ambiguous cases.
Conservative Treatment Options
Most clinicians recommend starting with non-surgical management. The first step is activity modification: reducing the specific movements that provoke the catching. For dancers, that may mean temporarily scaling back pointe work or jumps. For runners, reducing mileage or switching to flatter terrain can decrease the load on the FHL tendon. Icing the area behind the inner ankle and taking over-the-counter anti-inflammatory medication can help manage acute flare-ups.
Physical therapy plays an important role, particularly exercises that gently stretch the FHL tendon and strengthen the surrounding muscles to distribute load more evenly across the foot. Eccentric exercises, where the muscle lengthens under tension, are commonly prescribed for tendon problems throughout the body and are often applied here as well. A therapist may also use manual mobilization techniques to improve how the tendon glides through its tunnel.
Corticosteroid injections into the tendon sheath are sometimes used when pain and inflammation are significant. The steroid reduces swelling inside the tunnel and can break the cycle of catching and re-inflammation. However, repeated steroid injections near tendons carry a risk of weakening the tendon over time, so most practitioners limit the number of injections and use them as a bridge while other measures take effect rather than as a long-term solution.
For some patients, conservative treatment leads to progressive improvement and the triggering resolves. In cases where the pulley has only recently begun to thicken and the tendon itself is not yet damaged, the outlook with conservative care is generally good. The evidence gets thinner when you ask exactly how many patients avoid surgery, because trigger toe is rare enough that large treatment trials do not exist. Most of what we know comes from case reports and small series, so treatment decisions tend to be guided by the clinician’s experience with analogous conditions like trigger finger.
When Surgery Becomes the Answer
If several months of conservative treatment fail to relieve the catching, surgical release of the constricted tunnel is the standard next step. The goal is straightforward: cut or widen the fibrous tissue that is trapping the tendon so it can glide freely again.
For big-toe trigger (hallux saltans), the surgery is typically performed at the back of the ankle, because that is where the FHL tendon passes through the problematic tunnel. Posterior ankle endoscopy has emerged as a minimally invasive option. Through two small incisions at the back of the ankle, the surgeon can directly see the tendon catching, release the thickened fibrous tissue around it, and confirm that the tendon moves smoothly before closing.12PubMed. Endoscopic treatment of bilateral hallux saltans in an ordinary woman One important consideration during endoscopic release is the proximity of the tibial nerve, which runs close to the surgical field and must be carefully avoided.
When an os trigonum is present alongside the FHL entrapment, surgeons often remove the extra bone and release the tendon tunnel in the same procedure. This combined approach addresses both sources of impingement at once and is considered the standard surgical strategy when the two conditions overlap.11PubMed Central. Disorders of the Flexor Hallucis Longus and Os Trigonum
For lesser-toe triggering, the surgical site is different. Because the obstruction occurs at the toe’s own pulley system rather than up at the ankle, the release is performed through a small incision on the bottom of the foot near the affected toe. The concept is the same as an A1 pulley release for trigger finger: the thickened band is divided so the tendon can pass through without catching.
Recovery after surgical release varies depending on the approach. Endoscopic procedures generally allow earlier weight-bearing and a faster return to activity compared to open surgery. Dancers and athletes often want to know how soon they can return to full training; while individual timelines vary, many case reports describe return to sport within a few months of endoscopic release, assuming no complications.
Why Trigger Toe Is Underrecognized
Trigger finger is one of the most common hand conditions in the world, yet trigger toe remains relatively obscure. Part of the reason is simply frequency: the hand’s flexor pulleys are subjected to fine, repetitive gripping motions all day long, while the foot’s pulleys bear heavy loads but move through a narrower range of motion. The conditions that set up trigger toe, like extreme plantar flexion under load, are mostly limited to specific athletic or occupational settings.
Another factor is diagnostic awareness. Many clinicians outside of foot-and-ankle specialty practice do not routinely test for triggering in the toes, so the condition can be mislabeled as generic tendinitis, arthritis, or even a nerve problem. The existence of a structured pulley system in the lesser toes analogous to the one in the fingers was not even formally described until the late 1990s.8PubMed. Triggering of the lesser toes at a previously undescribed distal pulley system Advances in high-resolution ultrasound are helping to close this gap, because the imaging can now directly visualize the toe pulleys and measure their thickness in a way that was not practical with older equipment.10PubMed Central. High-resolution ultrasound of the annular pulley system in the toes: sonographic anatomy and pathological cases
If you have a toe that clicks, catches, or locks and the problem is not improving with rest, ask your provider specifically about trigger toe. A targeted physical exam or a dynamic ultrasound can confirm or rule it out relatively quickly, and catching it early gives conservative treatment the best chance of working before the fibrous thickening becomes too advanced for anything short of surgery to fix.