Fig.2A wedge of bone is removed from the first metatarsal
Fig.3The bone is realigned and fixed with a staple or plate and screws
What is hallux valgus?
Hallux valgus is a common condition frequently affecting women more than men.
Over time the big toe starts to bend and deviate towards the smaller toes causing a large, painful bump or “bunion” on the inside of the foot (Fig. 1). This can also be associated with the 2nd toe crossing the big toe. Hardened skin forms underneath the foot at the level of the ball of the 2nd toe. This combination of changes results in pain and redness over the bunion joint itself and underneath the foot. You may also experience bending or clawing of the 2nd toe with rubbing against footwear and pain may be felt on the hardened skin of the 2nd toe, a so-called “corn”.
“Hallux valgus” is the medical term for the big toe pointing towards the lesser toes too much. The “bunion” is the lump on the inside of the foot at the base of the hallux valgus, which is often painful.
Although we don’t fully understand what causes hallux valgus, there does seem to be a tendency for it to run in families but certainly the wearing of high heels seems to accelerate the development of bunions.
Treatment of hallux valgus can be either surgical or non-surgical.
None Surgical Treatment
Often changing the type of footwear, reducing heel height and getting shoes that are a little bit more spacious, particularly in the toe area, may be enough to reduce symptoms of pain or rubbing. If the symptoms improve sufficiently then often there is no need to do anything further. Sometimes the use of insoles or inserts in your shoes can help cushion and alleviate pain underneath the foot.
Surgical Treatment Options
If non-surgical treatments don’t work and the pain is too great and starts to interfere with daily activities or the use of everyday shoes then surgery can be used. This aims to change the position of the big toe and the foot, to reduce or even completely alleviate the pain that the bunion is causing.
The goal of surgery is to obtain pain relief. The fact that your foot and toes all become more “foot shaped” is considered a bonus!
Types of Operation
There are a number of procedures used to treat this condition surgically including the “scarf” and “chevron” procedures as described in other leaflets in this series. In more severe types of hallux valgus, a greater degree of correction is required. This is done further up in the middle of the foot, towards the base of the metatarsal bone. This procedure is known as a “proximal metatarsal osteotomy” and is the focus of this leaflet.
Proximal metatarsal osteotomy
This operation enables a greater correction of the foot than other procedures. It is used to both bring the toe back into a straightened position and also to move the metatarsal bone of the foot outwards and importantly downwards in order to share the load more evenly underneath the sole of the foot. This has the benefit of reducing the stress underneath the second toe and also reducing the width of the foot so that walking and shoe wear is more comfortable.
The operation involves making two cuts in the skin, one along the inside of the foot and another on the top of the foot in between the first and second toes. Through these incisions, the metatarsal bone of the foot can be cut and re-aligned (Fig 2). A wedge of bone is removed to realign the bone. The bunion can be removed and the soft tissues around the bunion can be re-tensioned to straighten the great toe (Fig 3).
Dissolvable stitches are often used to close the skin, meaning that none need to be removed. You will have a bulky dressing around the foot and you may either be given a wedge shaped shoe on which to walk with your heel or, if more stability is required, you may have a plaster of Paris slipper applied for a period of up to 6 weeks post operatively. You will be shown how to use crutches before discharge from hospital on the day of surgery.
This procedure is often done as a day case. Someone will need to take you home from the hospital and you will need someone to stay with you overnight following the operation. You may not drive yourself home.
During the first week you will need to elevate and rest the foot, as there is usually quite a lot of swelling associated with the operation. This will settle down but it will take 3 – 6 months for it to completely settle. The dressings are usually reduced and the wound inspected at about 1 – 2 weeks after surgery. You will usually be seen by your Consultant at about 6 weeks post-operatively who may arrange for an x-ray to make sure that the bone is healing and strong enough for you to start putting weight through your foot normally. It is unusual for anyone to be able to drive before 8 weeks after the surgery. You need to be able to perform a safe emergency stop before insurance companies are happy for you to drive fully on the roads again.
Complications may occasionally occur after surgery but are thankfully uncommon. They include: infection, non-union (bone not knitting where it’s been cut), injury to nerves or arteries (giving a numb patch on the foot), neuroma (tender spot on the scar, which may be painful if touched), scars, incomplete correction of the deformity, recurrence of the deformity, under correction, over correction, haematoma (a collection of blood under the wound), wound healing problems and foot pain, further surgery and the possibility of a deep vein thrombosis or pulmonary embolus (clot in the leg veins that can move to the lungs).
We hope this information is useful and if you have any more questions. Please feel free to discuss these with your Consultant.
If you have any difficulties before or after the procedure, please call the number below during office hours or the hospital directly.