Hallux Valgus - Bunion

What is Hallux valgus?

Hallux Valgus or bunion is one of the most common deformities of the foot. More than 23% of adults younger than 65 years old and more than 35% of older than 65 year olds have a bunion deformity. Ladies are more likely to get a bunion than men. However not all the deformities will cause problems. (1)

How does a Hallux Valgus deformity develop?

A mixture of factors as age, hyper-laxity (having overly mobile joints), family history and some environmental factors as wearing high heel shoes plays a role in developing Hallux Valgus. Ligaments and capsule supporting the joint at the base of the great toe stretches, lengthens and becomes unsupportive. Bone short of great toe called first metatarsal (M1) deviates inward, great toe itself deviates out. Toe rotates inward, muscles and tendons passing along the foot becomes a deforming force that worsens the deformity. Forefoot widens, shoes become too narrow and rub over the metatarsal (M1) head, causing it to inflame. Painful bunion develops. As deformity worsens 2nd toe assumes adaptive hammertoe deformity, which causes callosity over the back of the toe. 2nd metatarsal (M2) becomes proud at the sole of the foot and causes painful callosity known as metatarsalgia. Further worsening of the deformity causes over-crossing of the 2nd toe over the great toe often associated with sores between the toes. Regular shoes becomes too narrow or even too painful to wear and wears out too quickly.

What are the Treatment options?

Conservative measures as night splints, braces or spacers for Hallux Valgus are often ineffective, may slow but does not stop deformity progression and sometimes may exacerbate symptoms by rubbing over the painful bunion (2).

The most reliable solution is surgical treatment. After careful assessment and studying the X-Rays of your foot the most suitable treatment for your bunion can be determined. Most often it is MICA (minimally invasive Chevron and Akin). This surgical procedure is suitable for mild to severe bunions with rare exceptions (3).

MICA is carried out via few 4-6mm surgical stab incisions. Bony cuts are performed using special bone cutting burrs called Shanon burrs, spinning at low repetition but high torque. Constant water flow irrigates site of surgical cuts and prevents harmful bone overheating. Deformity correction and fixation with special beveled positional screws is performed Under X-Ray control. Fixation is strong, permitting weight bearing through operated leg using surgical stiff sole shoe on the same day.

Why should you choose minimally invasive bunion correction MICA over standard open surgery like Scarf and Akin?

• Small percutaneous incisions provides better cosmetic result

• Less post operative pain with less required analgesics.

• Better preserved range of motion

• Operation is performed without violating the capsule of the MTP joint, with rare exceptions.

• More versatile correction: M1 head rotation and distal metatarsal articular angle are corrected.

• Suitable for severe deformities

• Lower risk of recurrence (4)

What should you do postoperatively to achieve the best results?

• Keep operated leg elevated for 23hr a day for the first 2 weeks.

• Bandages are removed and wounds are checked during the post operative visit at 2 weeks.

• Special surgical shoe is used for 6 weeks. Full weight bearing with the shoe is permitted.

• You can wear rigid sole trainers from 6 weeks after surgery.

• Crutches are usually unnecessary with rare exceptions.

• Check X-Rays are performed 6 weeks after surgery including side and front views of the foot.

• Physical activities are gradually recommenced from 6 weeks after surgery.

• It is not recommended to drive for 6 weeks after surgery. A car with an automatic gear box can be driven a day after surgery if the left foot was operated.

What are the possible risks and complications?

Intraoperative

• Bone fracture

• Varus deformity (hypercorection)

• Nerve, vessel or tendon damage would cause numbness, bleeding or dysfunction respectively

• Great toe shortening

• Anaesthetic complications

Early complications

• Swelling, bruising, pain, bleeding

• Infections (Surgical Site infection SSI; Deep infection - osteomyelitis)

• Clot in the vein - Deep vein thrombosis (DVT), Pulmonary embolism (PE)

Late complications

• Recurrence about 7.7% (4).

• Avascular necrosis AVN - first metatarsal head bone infarct

• Nonunion

• Malunion

• Stiffness of the first metatarsophalangeal (MTP) joint

• First MTP joint arthritis.

• Metatarsalgija (pain in the sole of the forefoot)

• Scar hypertrophy - hard painful scar

• Complex regional pain syndrome (CRPS) - self limiting increased sensitivity, swelling, atrophy globally in the foot - 0,4%

• Screw migration, fracture, tissue irritation

• Need for further surgery

Even though the possible risks list is extensive, the rates of those risks are extremely rare and most of the risks are not reported in the published case series at all.

How to prepare for the surgery?

Preoperative period

• Have WEIGHT BEARING x-ray radiograms of the foot in the lateral and dorsoplantar planes available for the first appointment.

• Blood tests including Full Blood Count, Coagulation screen, Urea & Electrolytes, VitD not older than 1 month;

• Tell the doctor if you are using blood thinning medication

• You can use Aspirin throughout the procedure for cardiological reasons.

• Don’t use nicotine 6 weeks before and 6 weeks after surgery. This includes cigarettes, cigars, vape with nicotine etc. This will reduce the risk of

  • Thrombosis (DVT and PE),

  • The risk of infection by 2.04 times

  • The risk of nonunion by 2.5 times (5)

• Use Vit D (1000IU) and Calcium (500mg) supplement 6 weeks prior and 6 weeks after the surgery.

• Use high dose Vit C (500-1000mg) 6weeks before and 6 weeks after the surgery This will reduce the risk of CRPS.

• Dont use Non steroidal anti-inflammatory drugs NSAIDs Before and 6 weeks after surgery.

On the day of surgery

• Dont eat 8 hr before surgery

• You can drink clear water up to 3hr prior to surgery

• Take your medication that you use regularly on the morning of surgery.

Treatment with 4th generation Metatarsal Extraarticular Transverse & Akin META Osteotomy