The Bump on Your Foot: The Anatomy of a Bunion

Bunion anatomy and treatment is one of the most common topics Dr. Castelein addresses at Brighton Foot & Ankle. If you’ve ever noticed a large bump on the inside of your foot near the big toe, you may be dealing with a bunion.

What Is Bunion Anatomy?

A bunion forms when the first metatarsal, the long bone behind your big toe, shifts away from the second metatarsal and falls toward the inside of the foot. As this happens, the tendons and ligaments attached to the big toe pull it in the opposite direction, toward the second toe. The result is the painful, bony prominence you see on the inside of the foot.

The first metatarsal joint is one of the most important joints in the foot, responsible for absorbing roughly half of your body weight with every step. That’s why bunions can cause significant pain, swelling, and difficulty fitting into shoes.

What Causes Bunions?

Bunions are largely hereditary. A condition called hypermobility, where the first metatarsal joint moves more than the normal one to two degrees, can cause the bone to shift over time and lead to bunion formation. Footwear and lifestyle can accelerate the process but aren’t usually the root cause.

How Are Bunions Treated?

Conservative treatment options include supportive orthotics to slow progression, wide toe box shoes with mesh material that doesn’t press on the bunion, and silicone toe spacers for cushioning. These measures can manage pain and slow the bunion’s development but won’t correct the deformity.

When pain becomes significant, a wound develops, or shoes no longer fit comfortably, surgical correction is often the best long-term solution. Brighton Foot & Ankle offers several bunion correction procedures including the Lapiplasty, minimally invasive surgery, and first MPJ arthrodesis, tailored to each patient’s specific needs.

If you’re dealing with bunion anatomy treatment concerns, contact Brighton Foot & Ankle today to schedule a consultation with Dr. Castelein.