Bunions (Hallux Abducto Valgus)

What are Bunions ?

Bunions (HAV) is one of the most significant, painful, common and instantly recognisable forefoot deformities encountered

The term itself is used by patients describing the bony lump found on the side of the big toe, which is usually an adaptation of the positional change of the big toe. Hallux abducto valgus (HAV) is a medical term, which describes the position of the hallux (big toe) with respect to the connecting long bone of the mid foot (metatarsal), which together are called the 1st metatarsalphalangeal (MTPJ) joint.

HAV is an aquired deformity of the first MTPJ in which the hallux (big toe) deviates towards the lesser toes, dorsiflexes so the plantar aspect is more prominent laterally whilst the metatarsal (long bone) moves towards the midline, which makes walking difficult and often painful.

Bunions (HAV) are a progressive condition, which begins with a deviation of the big toe, gradually changing the angle of the bones over the years and slowly producing the characteristic bump, which becomes increasingly prominent. In most cases it will become painful at some stage depending on the severity of the bunion and the amount of activity of the individual, although some people may never have symptoms.

What causes Bunions?

Bunions can be caused by many combined factors including;

  • A deformity of the 1st metatarsophalangeal joint (MTPJ) of the big toe. This causes instability of the joint.

Deformity can be caused by;

  • Excessive pronation (feet rolling in), which transfers too much weight to the 1st MTPJ.
  • Family history (heriditary)
  • Foot type
  • Muscle imbalances
  • Ligament Dysfunction (laxity) hypermobile foot
  • Poor foot biomechanics
  • 1st Metatarsal length and shape difference
  • Poor fitting or inappropriate footwear
  • Age-Highly prevalent in 15-56% of people >50 years
  • Sex-Dominant in females 14F:1M
  • Race
  • Achilles contracture
  • Abnormal sesamoid (two small bones located under 1st MTPJ) position
  • Neuromuscular dysfunction
  • Diabetes
  • Activities that put undue stress on the feet

As the bunion progresses the range and quality of motion within the joint can be significantly reduced. Bunions (HAV) has many causes and more than one may be occurring at the same time.

Usually a bunion forms due to a combination of the above causes with the most common factor being a biomechanical abnormality of the foot causing excessive pronation (rolling in). When the foot over pronates (rolls in) the entire foot everts (twists to the centre). This causes the first-metatarsal-phalangeal joint (MTPJ) to twist as the big toe is fixed and planted securely on the ground as the foot is moving inwards. As the foot moves on to the toes for propulsion the 1st (MTPJ) rotates as the first toe tries to extend.

It is this rotating that causes irritation of the bone and surrounding joint. When bone is irritated it will grow in order to protect its structure. As the joint is irritated the bony growths form on the areas of greatest rotation irritation. This in turn causes greater irritation as the joint will now jam on the excess bone formation. And the cycle repeats with joint jamming, bone formation, which causes greater joint jamming and so on. When this poor mechanical position is coupled with ligamentous laxity (flexibility), high activity, a genetic predisposition for bunions (HAV) or poor fitting footwear, the bunion is likely to form and cause significant problems.

Like in many other conditions, it is important to understand what is causing the abnormality, and at what level the degeneration has reached. HAV has four significant stages which may take many years to progress from one stage to another and each stage gives an indication to what level of degeneration is present.

Symptoms

Symptoms may include;

  • Big toe that turns in toward the other toes (may overlap second or even third toe)
  • Firm bump on the outside edge of the foot (1st MTPJ) of the big toe migrating outwards
  • Restricted or painful motion of the big toe
  • Foot pain and stiffness
  • Inflammation and redness
  • A burning sensation
  • Possible numbness

Symptoms occur most often when wearing shoes that crowd the toes, such as shoes with a tight toe box or high heels. In addition, spending long periods of time on your feet can aggravate the symptoms of bunions

Diagnosis

A visual observation method in combination with a bunion angle measurement are employed in assessing the severity of HAV in conjunction with patient symptoms to determine what type of treatment is suitable.

Because bunions are progressive, they don’t go away, and will usually get worse over time. But not all cases are alike – some bunions progress more rapidly than others.

Once your podiatrist has evaluated your bunion, a treatment plan can be developed that is suited to your needs.

Non-Surgical Treatment

Sometimes observation of the bunion is all that’s needed. To reduce the chance of damage to the joint, periodic evaluation is advised.

In many other cases, however, some type of treatment is needed. Early treatments are aimed at relieving pressure and easing the pain of bunions, but they won’t reverse the progression of the deformity itself. These include:

  • Changes in footwear- Wearing the right kind of footwear is very important. Choose shoes that have a wide toe box, making sure the top of the shoe doesn't rub against the bunion and forgo shoes with pointed toes or high heels, which may aggravate the condition.
  • Padding and Taping- Pads placed over the area of the bunion can help minimise pain. Taping helps to keep the foot in a normal position, reducing stress and pain.
  • Activity modifications- Avoid activity that causes bunion pain, including standing for long periods of time.
  • Medications- Oral nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, may be recommended to reduce pain and inflammation.
  • Icing- Applying an ice pack several times a day helps reduce inflammation and pain.
  • Orthotics- Are useful in maintaining foot function, help improve the function of the big toe joint ( 1st MTPJ) as it allows it to move in the correct position. The foot is also realigned with the aid of orthotics, which helps prevent further degeneration and/or reduce symptoms of bunions (HAV) in most stages of its deformity. Although they cannot cure a bunion they can slow its progression, reduce symptoms and prevent the deformity worsening making your foot more comfortable within a shoe.

In conjunction with orthotics, patients may require debridement of corns and calluses due to extra forces produced on the foot. Orthotics will also help the function of the big toe joint

  • Exercise and manipulation- can relieve inflammation and pain.

Even though bunions are a common foot deformity, there are misconceptions about them. Many people may unnecessarily suffer the pain of bunions for years before seeking treatment.

If you have a bunion or think you have a bunion contact us for an assessment on 02 9906 2544

 

WARNING : This information is for educational purposes only and is not intended to replace professional podiatric advice. Treatment will vary between individuals depending upon your diagnosis and presenting complaint. An accurate diagnosis can only be made following a personal consultation with a Podiatrist.