Patient Information for Bunion Surgery

General

A bunion (hallux valgus) is the movement of the first metatarsal away from the second metatarsal with the big toe drifting towards the second toe. Most patients complain of pain, a prominent joint, and problems with shoes. Bunions are considered to be a progressive condition. The cause of bunions is unknown, but possible factors include a family history, foot function, and footwear. It is thought to affect 23% of people aged between 16 and 35 and 35.7% of people over 65 years.

This is a clinical diagnosis made by examining the foot. The severity of the condition is assessed by an X-ray. There is no direct correlation between the size of the deformity and the degree of symptoms experienced.

Treatment options

Conservative care

Conservative care is aimed at managing the symptoms using:

• Wide fitting shoes
• Insoles
• Night splints (children)
• Painkillers and anti-inflammatories

Surgical Management

The aim of the surgery is to realign the first metatarsal almost parallel to the second metatarsal. This will move the big toe back into a straight position. This is achieved by moving the first metatarsal back into its proper position by cutting the bone. Sometimes re-balancing the soft tissue around the joint or taking a small wedge of bone out of the big toe is also required (akin). The outcome of your operation will be dependent on the quality of your joint, the degree of arthritis present. There are numerous operations to correct bunions, but essentially, they fall into two categories: transposition and rotational procedures (see diagrams). Transposition osteotomies include the ‘scarf’ and the ‘capital’. Rotational procedures include the ‘Lapidus’.

A transposition osteotomy such as a scarf or capital osteotomy is where the bone is cut and moved across.  The amount of correction available is restricted by the width of the bone.  If moved further than this, instability may occur.  It is ideally suited to moderate deformities. In severe cases a rotational procedure such as a ‘Lapidus’ is preferred.  Here a greater degree of correction is available. This operation also takes longer to heal and to settle down. Either procedure may be combined with an ‘akin’ to help move the big toe to a straight position.

You will be advised on the appropriate procedure to correct your deformity.  Ultimately, it is your decision as to whether you proceed with surgery or continue with conservative care.

Alternative procedures

The common procedures carried out by Professor Tagoe are the three described in this information booklet (scarf, capital and Lapidus).
There are other options available. One type of procedure which has gained popularity is ‘Minimally Invasive Surgery’ (MIS). This involves one or more small incisions to cut the bone under x-ray guidance, with the objective to reduce surgical and recovery times. However, a number of reviews of the evidence showed these techniques have high rates of complications including recurrence of the bunion (up to 60%), malalignment (up to 61%) and stiffness in the big toe joint. 

Possible outcomes

Depending on the quality of your big toe joint i.e. the presence and degree of ‘wear and tear’ arthritis, the risk of joint stiffness and/or pain in the big toe joint following bunion surgery will be increased. If the arthritis is severe, you may be offered an alternative procedure such as a big toe joint fusion. Everyone having bunion surgery should expect some reduction in range of motion at their big toe joint. It is also possible that pain may be transferred to another part of the foot. This may be temporary, as you walk slightly differently during recovery. In some cases, this is permanent or requires further surgery.

Scarf osteotomy

This is a transposition osteotomy. It is normally indicated for mild to moderate deformities. The new position of the first metatarsal is maintained with two screws which enables stability. Once the bone has fully healed, the screws are no longer required. However, we only remove them if they cause irritation.

Possible risks following capital and Scarf osteotomies

Although these are stable osteotomies, however, a fracture is a possibility particularly in patients who are very active in the initial stages of the recovery or with weaker bone. In some the alignment is lost and requires another surgery to fix. Joint stiffness and pain in cases where there is arthritis present prior to surgery. Once the bone has fully healed, the screw(s) are no longer required. However, we only remove fixation if it causes irritation.

Possible risks with a Lapidus

Due to the corrective power of this procedure, there is a risk of overcorrection of the bunion, which may result in the big toe drifting further away from the second or pain and arthritis in the big toe joint. The failure of the two bones to unite in a Survey of 100 patients operated on by Professor Tagoe was 2%, the most recent systematic review reported a higher rate of 3.8%. A non-union may require revision surgery.

Outcome

An audit of 100 patients undergoing this operation by Professor Tagoe was carried. A 100-point clinical rating system was used to assess pain, function and alignment, a score of 100 being perfect. The average score before surgery was 47.33. Following the surgery, the average outcome was 91.08 within our department. The risk of a non-union at the fusion site was 2%..

Discharge

Before you leave the hospital, you will be given an Aircast boot following Lapidus procedures or a post-operative sandal in the case of a capital or Scarf osteotomy. You will be shown how to partially weight bear on the foot using crutches. Post-operative painkillers will be dispensed by the nurses along with your next appointment.

You should arrange to go home by car or taxi with an escort. You should have someone with you for the first 24 hours in case you feel unwell.

Recovery

Full recovery takes between seven and twelve months

Possible complications

Most patients have an uneventful recovery. Outlined below are the common problems or those rare complications with serious outcomes. In cases where we don’t have accurate audit we have used published results from the podiatric literature. These are accompanied by an asterisk *

• Prolonged swelling taking more than 6 months to resolve occurs 1 in every 500 operations*
• Haematoma – a painful accumulation of blood within the operation site. /li>
• Thick and or sensitive scar.
• Infection of soft tissue. The incidence is 1 in every 83 operations*
• Delayed healing of soft tissue.
• Circulatory impairment with tissue loss occurred in 3 out of 9000 patients over a 10-year period
• Venous thromboembolism (VTE) (a blood clot within the veins) may affect the legs or the lungs and is potentially a life-threatening condition. Within the published literature, the overall incidence of VTE is thought to be 0.9% in foot and ankle surgery.
• Chronic pain syndrome: this is where the nervous system dealing with pain over reacts in a prolonged manner often to a minor incident. This normally requires management by specialist in this condition and doesn’t always resolve. This is a rare complication with no audit data available.

Specific complications published in the general literature following bunion surgery :

• Infection (2.6%*)
• Delayed union (slow healing)
• Fracture
• Joint stiffness and pain
• Reoccurrence of symptoms or deformity (4.9%*)
• Fixation irritation (3.8%*)
• Transfer pain (6.3%*)

The risk of having a complication can be minimised when the patient and all those concerned with the operation and aftercare work together. This starts with the pre-operative screening and continues through to the rehabilitation exercises.

Pre-operative screening of your health allows us to determine whether you are fit for surgery. It is important that you disclose your full medical history. If there is a query regarding your health, then further investigations or the advice of other surgical and medical specialties will be sought. Professor Tagoe and the theatre team will ensure that the operation is performed effectively and with the minimum of trauma.

You can improve the healing process and reduce the risks of complications by:

• Adhering to the post-operative instructions which include resting and elevating the operated leg. Keeping the wound clean and dry until advised otherwise is essential. Please ask the nurse or Podiatric surgeon if you are not sure what to do.
• Having a healthy diet is important. This provides the nutrition required for healing.
• Smoking is associated with a 20% increased risk of delayed or non-healing of bones.
• Alcohol can interact with the drugs that we will prescribe and in excess can impair wound healing.
• Post-operative mobilisation will be advised. This helps improve the flexibility, strength and stability of your foot