What is a bunion?
A bunion, also known as hallux valgus, is a lateral deviation of the great toe. This lateral deviation creates a bump on the medial aspect of the metatarsal head.
What causes bunions?
The majority of bunions are caused by poor fitting shoes. Footwear with a narrow toe box and high heels push the great toe medially. As a result, the long tendon that dorsiflexes the great toe lies lateral to the metatarsalphalangeal joint, pulling the toe into a valgus position.
Other possible causes are rheumatoid arthritis and dorsiflexion of the great toe, which may produce a medial force and ligamentous laxity, all of which lead to instability. Excessive pronation may also cause a medial force, which may lead to a bunion.
It is thought that bunions have a hereditary component due to its pronation characteristic. A tight Achilles tendon will cause the patient to walk with their toes pointing out, which can cause excessive pronation and a bunion may develop.
Signs and Symptoms
It must first be noted that bunions are three times more common in women than men. The most common symptoms are bunion irritation, pain and/or ulceration, joint pain and calluses located under the second metatarsal head and the medial aspect of the interphalangeal joint of the great toe. As the big toe bumps into the second toe, the pressure may cause an ingrown toenail.
A symptom that may cause secondary problems is a hammer toe, where the second toe over-rides the great toe and a corn will develop on the IP joint.
Consideration for Bunion Surgery
Surgery should be done for pain, increased deformity, decreased function and/or the inability to wear "reasonable" shoes. It should rarely, if at all, be done for cosmetic reasons only. Be sure the procedure is fixing the cause of the problem and not just the bunion itself.
Conservative treatment may decrease the progression of a bunion, but it does not eliminate or reverse it. The patient can accommodate the bunion with properly fitting footwear that consists of a large toe box, rocker-bottom soles, low heels and custom molded shoes. Other possibilities include toe spacers and/or relief padding around the bunion, but NOT over.
Physical therapy may be prescribed for joint mobilizations of the lateral joint capsule, heel cord stretching, strengthening of the muscles that flex the great toe, and orthotics to control pronation.
There are numerous surgeries performed for bunions. An exostectomy, removal of the medial prominence, a lateral release and sometimes other soft tissue releases and medial capsular reinforcements are done. Presently, most often an osteotomy is done to realign the first metatarsal and the great toe.
General Post-operative Rehabilitation
• Control pain and edema
• Scar massage
• Restore ROM at the tarsal joint
• Restore PROM of great toe
• Progressive heel cord stretching
• Mobilizations of the first ray
• Strengthen flexors of the great toe
• Gait training
• Foot wear modification