Can You Have a Bone Spur on the Side of Your Foot?

Bone spurs absolutely can form on the side of your foot, and they do so more often than most people realize. The lateral border of the foot, from the heel to the base of the little toe, has multiple sites where bony outgrowths develop in response to mechanical stress, ligament tension, or underlying joint disease. These spurs go by different names depending on their exact location and how they form, but the short answer is that the side of the foot is one of the more common places for them to appear.

Where Exactly They Show Up

The side of the foot is not one uniform surface. It has several distinct zones where bone spurs tend to grow, each with its own triggers and characteristics. The most common locations along the lateral foot include the outer edge of the heel bone, the base of the fifth metatarsal (the long bone leading to your little toe), and the outer ankle area near the talus.

On the heel, calcaneal spurs are well documented. Most people think of heel spurs as forming on the bottom of the foot, but bony projections also develop on the sides and back of the calcaneus. A study using MRI found that calcaneal spurs were strongly associated with plantar fasciitis and with wasting of the small muscle on the outer edge of the foot, with a calcaneal spur being about three and a half times more likely in patients who showed that muscle atrophy.

At the base of the fifth metatarsal, traction-type bone spurs develop where the peroneus brevis tendon and the lateral band of the plantar fascia attach. One case series documented chronic traction osteophyte formation at this site in speedway motorcycle racers, whose feet endure repeated lateral loading and torque.

You do not need to be a motorcycle racer for this to happen. Anyone who repeatedly stresses the outer foot through running, hiking on uneven terrain, or wearing shoes that crowd the forefoot can develop bony changes at this attachment point over time.

Near the outer ankle, the talus bone can develop bony outgrowths where ligaments anchor into it. Research examining these growths found that on the lateral side of the talus, the outgrowths tend to form outside the joint itself, pulled up by the tension of the joint capsule and surrounding ligaments, rather than growing inside the joint the way classic arthritis-related spurs do on the inner ankle.

A related finding described a symptomatic bony bump on the front-outer corner of the talus, right at the spot where the anterior talofibular ligament inserts, in patients with chronically painful ankles that had been previously sprained.

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How Lateral Foot Spurs Form

The mechanism behind a bone spur on the side of the foot usually comes down to one of two processes, and understanding which one is at work helps explain why treatments differ.

The first is traction. Tendons and ligaments attach to bone, and when those soft tissues are under chronic tension, the bone at the attachment site gradually remodels and builds outward. Think of it as the bone responding to years of being pulled in one direction. The fifth metatarsal base spurs in the speedway riders are a textbook example of traction-driven growth, and the lateral talar outgrowths near the ankle joint follow the same pattern.

The second is joint degeneration. When cartilage in a joint wears down, the exposed bone edges sometimes respond by growing new bone at the margins, creating classic joint-margin spurs. This process tends to happen more on the inner (medial) side of the ankle, but it can affect the lateral side too, especially after injuries that altered how the joint bears weight.

In practice, many lateral foot spurs involve both mechanisms to some degree. A person who repeatedly rolls an ankle might end up with ligament-traction spurs at the talus and also develop degenerative spurs at the subtalar joint over the following years as the altered mechanics grind down cartilage.

When a Bump on the Side Is Not a Bone Spur

Not every hard lump on the outer edge of the foot is a spur, and getting the distinction right matters because the treatment paths diverge considerably.

One common mimic is an accessory ossicle, which is a small extra bone that some people are born with. These normal anatomical variants show up frequently on imaging of the foot and ankle and are often misidentified. They can be mistaken for fracture fragments or loose bodies, or they may not be recognized as the actual source of a patient’s pain.

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The os peroneum, a small round bone embedded in the peroneus longus tendon near the outer midfoot, is one of the more frequently encountered accessory ossicles in this region. If it becomes irritated or fractured, it can cause lateral foot pain that feels exactly like a bone spur problem.

In adolescents and teenagers, a painful prominence at the base of the fifth metatarsal is more likely to be Iselin’s disease than a bone spur. This condition involves irritation of the growth plate (apophysis) at that site, typically flaring up in active young athletes who run and jump. On X-ray, the fragmented or widened growth plate can look like an abnormal bony bump, but it is a growth-related issue that usually resolves with rest and time rather than requiring the interventions an adult bone spur might need.

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A tailor’s bunion, or bunionette, is yet another source of a prominent bump on the outer forefoot. This involves the head of the fifth metatarsal angling outward, sometimes with overlying inflammation. It is a structural misalignment rather than an outright bone spur, though some bunionettes do have a bony ridge or spur on their surface that contributes to the irritation.

Symptoms and Nerve Involvement

A bone spur on the side of the foot does not always hurt. Many are discovered incidentally on X-rays taken for other reasons and never cause any trouble. When they do become symptomatic, the pain usually comes not from the spur itself but from its interactions with surrounding soft tissues.

Shoes are the most obvious culprit. A bony prominence on the lateral foot sits right where the shoe’s upper presses inward, creating a pressure point that can lead to redness, callus formation, bursitis (a fluid-filled sac that the body builds as a cushion), and sharp pain with every step. Wider or softer shoes sometimes resolve the problem entirely.

A more serious complication arises when a lateral foot spur compresses a nearby nerve. The sural nerve runs along the back and outer side of the lower leg, curving behind the outer ankle bone and continuing along the lateral foot. Because of this path, a bone spur near the outer ankle or lateral heel can press against the nerve and trigger burning pain, heightened skin sensitivity, and in some cases a pain syndrome that spreads beyond the original site.

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If you have a bump on the side of your foot accompanied by burning, tingling, or numbness running along the outer ankle or foot, nerve involvement should be considered rather than assuming the spur is simply rubbing against your shoe.

Inflammatory Conditions That Drive Lateral Spurs

Most lateral foot spurs stem from mechanical wear and tear, but systemic inflammatory diseases can accelerate or even directly cause bone spur formation in patterns that differ from ordinary osteoarthritis.

Psoriatic arthritis stands out in this regard. Detailed imaging studies have shown that bone spurs in psoriatic arthritis tend to form at entheseal regions, the spots where tendons and ligaments attach to bone. These entheseal spurs are prominent in psoriatic arthritis patients but rare in patients with ordinary osteoarthritis of the hands, where spurs instead grow at the cartilage-bone boundary inside the joint itself.

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This distinction matters for the lateral foot because the outer border is loaded with entheseal attachment points. If you have psoriatic arthritis or another spondyloarthropathy, bony growths along the side of your foot may be driven by the inflammatory disease itself, and treating only the local symptoms without addressing the underlying condition tends to produce disappointing results.

Gout, reactive arthritis, and ankylosing spondylitis can similarly cause entheseal bone changes in the foot, though the patterns vary. The important takeaway is that a bone spur on the side of your foot that appeared without an obvious mechanical trigger, especially if you also have joint pain or stiffness elsewhere, warrants a broader medical evaluation rather than just a local X-ray.

How They Are Diagnosed

A standard weight-bearing X-ray is usually the first step when a lateral foot spur is suspected. Most bony outgrowths are visible on plain films, and the location and shape of the spur give clues about whether it formed from joint degeneration, ligament traction, or an underlying growth. A spur at a joint margin looks different from one projecting off a tendon attachment point.

The diagnostic challenge is distinguishing a true bone spur from the look-alikes discussed earlier. Accessory ossicles have smooth, rounded cortical borders and appear as separate small bones rather than projections from a larger bone, but telling them apart from old avulsion fracture fragments can be tricky on a single X-ray.

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In ambiguous cases, comparison views of the opposite foot help: an accessory ossicle is often present on both sides, while a post-traumatic spur or fracture fragment usually is not.

MRI or ultrasound gets involved when soft tissue damage is suspected alongside the spur. If a lateral ankle spur is pressing on a tendon or nerve, the bony bump alone does not tell the whole story. Imaging the surrounding tendons, bursae, and nerve sheaths helps determine whether surgery on the spur would actually fix the problem, or whether the real issue is the inflamed tissue next to it.

Treatment Without Surgery

The first line of treatment for a symptomatic lateral foot spur is almost always conservative, and for many people it is the only treatment needed. The goal is not to make the spur disappear but to reduce the irritation it causes.

Footwear changes: Wider shoes with a softer lateral upper eliminate the direct pressure point. For spurs near the fifth metatarsal head, a shoe with a wider toe box often provides immediate relief.
Padding and orthotics: Donut-shaped felt pads placed around the spur offload pressure from the prominence. Custom orthotics can redistribute weight away from the lateral foot if overpronation or supination is contributing to the problem.
Anti-inflammatory measures: Ice, oral anti-inflammatories, and occasionally a corticosteroid injection into an overlying bursa can calm an acute flare. These do not shrink the spur, but they can break the cycle of inflammation and pain.

Shockwave therapy has been studied primarily for plantar heel spurs rather than lateral foot spurs, but the findings are instructive. In one study of symptomatic heel spurs treated with extracorporeal shockwave therapy, about two-thirds of patients achieved excellent pain relief and another roughly 16 percent had good improvement. However, imaging afterward showed no meaningful reduction in spur size. Pain relief had no correlation with whether the spur changed on X-ray.

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This reinforces a broader principle about bone spurs anywhere in the foot: the spur itself is often not the direct pain generator. Treating the surrounding soft tissue irritation can resolve symptoms even though the bony bump remains unchanged.

When Surgery Becomes the Conversation

Surgery for a lateral foot bone spur enters the picture when conservative measures have been tried for several months without adequate relief, or when the spur is causing structural problems like tendon damage or nerve compression that will not improve on their own.

The most straightforward procedure is an exostectomy, which simply shaves down the bony prominence. For a spur at the base of the fifth metatarsal or on the lateral calcaneus, this can often be done through a small incision. Recovery involves several weeks of limited weight-bearing and careful wound management on the outer foot, where shoe pressure during healing is a concern.

In cases where the spur formed because of an underlying alignment problem, removing the bump alone may not be enough. If the foot’s lateral column is chronically overloaded because of how the heel or midfoot joints are positioned, the spur can recur or new symptoms can develop. In those situations, a realignment procedure or corrective osteotomy may be recommended alongside or instead of simple spur removal. This is a bigger operation with a longer recovery, and the decision usually involves detailed imaging and gait analysis beforehand.

For spurs driven by inflammatory arthritis, surgical removal without systemic disease control is generally a losing proposition. The inflammatory process that built the spur in the first place will continue to lay down new bone. Rheumatologic treatment to quiet the underlying disease is the priority, with surgery reserved for mechanical problems that persist despite good disease management.

Spurs That Form After Injuries

Ankle sprains, stress fractures, and calcaneal fractures can all leave behind bony remodeling that manifests as a spur on the side of the foot months or years later. The lateral talar exostosis described in chronically painful sprained ankles is a good example: patients who never fully recovered from a significant ankle sprain were found to have a symptomatic bony bump at the ligament attachment site on the outer talus.

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This post-traumatic bone formation is essentially the body’s overenthusiastic repair response. The injured ligament heals, but the bone at the attachment site lays down extra material as if reinforcing a weak point. Over time, that extra material solidifies into a spur that can impinge on adjacent structures or simply hurt when pressed. If you have lingering outer ankle pain years after a sprain that was supposedly healed, a post-traumatic spur is worth considering as a possible explanation.

Calcaneal fractures that healed with some widening of the heel bone can leave lateral bony prominences that press against the outer shoe wall or irritate the peroneal tendons running behind the outer ankle bone. These are technically malunion-related spurs rather than spontaneous growths, but the patient’s experience, a painful hard bump on the side of the foot that was not there before the injury, is the same.

The Lateral Foot in Evolutionary Context

The human foot’s lateral column (the outer two metatarsals and the cuboid) evolved to be relatively rigid compared to those of other great apes, which is part of what allows efficient push-off during walking and running. Research comparing metatarsal joint surfaces in humans, apes, and fossil hominins found that humans have a distinctly flat fourth metatarsal joint surface, while apes have a more curved one, reflecting a stiffer lateral column in humans.

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That rigidity is an advantage for bipedal locomotion, but it also means the lateral foot absorbs repetitive stress without much give. Bones that flex less tend to remodel more aggressively at points of high stress concentration, which is part of why traction spurs and entheseal outgrowths are so common along the outer border of the foot. The same structural stiffness that makes human walking efficient also sets the stage for bony adaptation when forces exceed what the tissues can quietly absorb. Add modern hard surfaces, restrictive footwear, and decades of walking on pavement, and the lateral foot’s evolutionary design meets conditions it was never quite shaped for.

1
PubMed Central. Plantar fasciitis and calcaneal spur formation are associated with abductor digiti minimi atrophy on MRI of the foot
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Foot and Ankle Surgery. Traction osteophyte formation of the fifth metatarsal: ‘Speedway rider’s foot’
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PubMed. Anterior ankle impingement and talar bony outgrowths: osteophyte or enthesophyte? Paleopathologic and cadaveric study with imaging correlation
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PubMed. Excrescent lesion: a diagnosis of lateral talar exostosis in chronically symptomatic sprained ankles
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PubMed Central. Common accessory ossicles of the foot: imaging features, pitfalls and associated pathology
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PubMed Central. Iselin’s disease: Traction apophysitis of the fifth metatarsal base, a rare cause of lateral foot pain
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PubMed Central. Overview of nerve entrapment syndromes in the foot and ankle
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PubMed Central. Inflammatory bone spur formation in psoriatic arthritis is different from bone spur formation in hand osteoarthritis
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PubMed. Effects of extracorporal shock wave therapy on symptomatic heel spurs: a correlation between clinical outcome and radiologic changes
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Elsevier / PubMed Central. Proximal metatarsal articular surface shape and the evolution of a rigid lateral foot in hominins