A bunion is a very common foot deformity that develops over the first metatarsal phalageal joint of the big toe of the foot. The joint that joins the big toe to the foot is called the first MTP joint. When it becomes prominent and the big toe starts to become crooked this is known as a bunion. The term referring to deformity of the big toe as it becomes crooked is called Hallux Valgus. It is the bump itself that is known as the bunion. When it gets red and swollen over the bunion because it gets sore this is usually due to an inflamed soft tissue over the underlying bone.
Many problems that occur in the feet are the result of abnormal pressure or rubbing. One way of understanding what happens in the foot due to abnormal pressure is to view the foot simply. Our simple model of a foot is made up of hard bone covered by soft tissue that we then put a shoe on top of. Most of the symptoms that develop over time are because the skin and soft tissue are caught between the hard bone on the inside and the hard shoe on the outside. Any prominence, or bump, in the bone will make the situation even worse over the bump. Skin responds to constant rubbing and pressure by forming a callus. The soft tissues underneath the skin respond to the constant pressure and rubbing by growing thicker. Both the thick callus and the thick soft tissues under the callus are irritated and painful. The answer to decreasing the pain is to remove the pressure. The pressure can be reduced from the outside by changing the pressure from the shoes. The pressure can be reduced from the inside by surgically removing any bony prominence.
The dominant symptom of a bunion is a big bulging bump on the inside of the base of the big toe. Other symptoms include swelling, soreness and redness around the big toe joint, a tough callus at the bottom of the big toe and persistent or intermittent pain.
Orthopaedic surgeons diagnose bunions on the basis of physical examination and weight bearing x-rays. Two angles are assessed, the intermetatarsal angle, that is between the first and second metatarsals (the bones that lead up to the base of the toes). If this angle exceeds 9? (the angle found in the healthy foot) it is abnormal and referred to as metatarsus primus varus. the hallux valgus angle, that is, the angle of the big toe as it drifts toward the small toe. An angle that exceeds 15? is considered to be a sign of pathology.
Non Surgical Treatment
Treatment may be surgical or non-surgical. The goal of non-surgical treatment is to relieve pressure on the foot and to prevent pressure sores and foot ulcers. This is accomplished by prescribing accommodative shoes with a wide toe box - sandals or extra depth shoes with soft moulded insoles. It may also be possible to relax the leather on shoes to make room for a bunion.
Bunion surgery is usually done as an out patient procedure, so the patient does not have to stay in hospital overnight although it is usually performed under a general anesthetic. The procedure involves the surgeon making a cut on the inside of the big toe joint and removing excess bone whilst also repositioning ligaments and tendons. The joint may be fixed with screws or wires, which may be dissolve, or may be removed at a later date or in some cases, remain in the foot permanently. After the operation the foot will be immobilized, often in a cast for 4 to 8 weeks to keep the bones in alignment. Crutches will usually be issued to help the patient get around. After this period, the foot will be assessed to check the bones have healed correctly. At which point full weight bearing may be gradually introduced.
Shoes that possess tapering toe boxes should be avoided if you have a bunion, as narrow toe boxes will hasten the progression of your bunion deformity. In some cases, conservative measures, including switching to appropriate footwear, may not have the desired effect, and your podiatrist may recommend for you a surgical procedure known as a bunionectomy.