A bunion, also called a hallux valgus, is an enlargement of bone or soft tissues around the joint at the base of the big toe that results in the formation of a bump. The bone that joins the big toe with the first metatarsal bone thickens and enlarges, tightening the tendons, which in turn causes the base of the big toe to angle out resulting in a painful bony deformity.

Causes

The most common cause of a bunion is prolonged wearing of ill-fitting footwear that compresses the toes into unnatural positions. This can include high heeled shoes, narrow shoes, shoes that are too small or pointy shoes with a narrow toe box. Genetics and certain disease conditions such as arthritis or polio may increase the risk of developing a bunion.

Bunions are much more prevalent in women than men, which may be associated with the use of heels and fashionable shoes by women. The diagnosis of a bunion by an orthopaedic surgeon includes taking a medical history, and performing a physical examination to assess the extent of misalignment and damage to the soft tissues. Your doctor may order X-rays to help determine the extent of damage and deformity of the toe joints.

Signs and symptoms

The signs and symptoms associated with bunions are as follows:

	Pain with ambulation when wearing shoes
	Swelling with red, calloused skin at the base of the big toe
	Decreased- mobility in the big toe
	Inward turning of the big toe toward the second toe
	Formation of corns and calluses at the overlapping of the big toe and second toe

Treatment

Your surgeon initially will recommend conservative treatment measures with the goal of reducing or eliminating foot pain.

Such measures include wearing properly fitted shoes with specially designed shoe inserts, padding, or taping of bunions. Physical therapy and certain medications may be prescribed for relieving pain and inflammation. If conservative measures fail to treat the bunion pain, then your surgeon may recommend a surgical procedure to remove the bunion. There are many surgical options to treat a bunion but the common goal is to realign the joint, correct the deformity, and to relieve pain and discomfort. Osteotomy is a common type of bunion surgery that involves surgical cutting and realignment of the toe joint. The orthopaedic surgeon selects the appropriate surgical procedure based on the patient’s presentation.

There are 3 types of osteotomies, namely akin osteotomy, chevron osteotomy, and scarf osteotomy.

Akin Osteotomy

Akin osteotomy - is usually performed under local anaesthesia where your toe will be numbed and you will not feel any pain during the procedure. Your surgeon will make an incision along your big toe. The joint capsule is then opened, and the bunion is removed using a surgical saw. Your surgeon will then remove a wedge of bone from your big toe. Your toe is then brought back to its normal anatomical position and held together with surgical staples. The mobility of your big toe is examined, and the capsule and wound are re-approximated with sutures.
Chevron osteotomy A chevron osteotomy is usually recommended for mild to moderate bunion deformities. During this procedure, your surgeon will make an incision over your big toe. The joint capsule is opened and the bunion is removed using a surgical saw. A V shaped cut is made on the metatarsal bone of your big toe, and the bones are moved to bring your toe into its normal anatomical position. Screws or pins are used to hold the bones in their new position until healing occurs. The mobility of your big toe is examined, and the capsule and wound are re-approximated with sutures.

Impingement Test

As part of the physical examination, your doctor will likely conduct the impingement test. For this test, your doctor will bring your knee up towards your chest and then rotate it inward towards your opposite shoulder. If this recreates your hip pain, the test result is positive for impingement.

Scarf Osteotomy

Scarf osteotomy is usually recommended for moderate to severe bunion deformities and is performed under general anaesthesia, where you will be asleep during the entire procedure.

Computed tomography (CT) scans - More detailed than a plain x-ray, CT scans help see the exact abnormal shape of your hip. Your surgeon will make an incision along your big toe and open up the joint capsule to expose the bump. The bump on your big toe is then removed using a bone saw. Your first metatarsal bone is then cut in a Z shape and realigned to correct the deformity. Your surgeon will fix the cut bone with pins or screws. The joint capsule and surgical wounds are then re-approximated using dissolvable sutures keeping your toe in a straight position.

Risks and complications

As with any surgery, complications can occur. Apart from general complications related to all surgeries, complications after bunion surgery can include:
Infection
Recurrence of the bunion
Nerve damage
Unresolved pain


In rare cases, a second surgery may be necessary to correct the problems.