What is a bunion (hallux valgus), causes and symptoms?
A bunion is a bump or prominence on the inside of the foot, below the big toe. A bunion occurs when the long bone (metatarsal) that connects to the big toe, deviates inward. This movement creates the bunion prominence on the inside of the foot. The prominence is normal bone in the wrong position rather than the growth of new bone.
The reason the metatarsal moves is related to an instability in a mid-foot joint that allows the bone to swing inward.
Bunions are a common condition with 1 in 4 people having a bunion. Whilst men can also develop bunions, they are more prevalent in women (9:1 ratio). For most people, it is inherited; family history and genetics play a large role in the likelihood of getting bunions, with conditions such as flat feet and lax ligaments may also play a part.
A common misconception is footwear being an initial cause of bunions. This is generally not the case but can make an existing bunion worse.
Initially, there may be no symptoms at all, just a wider foot with a prominence. As the bunion progresses, it can have an impact in footwear but not normally when barefoot. The most common symptoms are pain and discomfort.
As the bunion progresses, the big toe may start to deviate toward the second toe making shoe fitting difficult due to the increased width. If left untreated, bunions can cause the biomechanics of the foot to change, creating a knock-on effect on the remainder of the foot, leading to other secondary symptoms such as metatarsalgia (pain under the balls of the toes), hammer toes (curled or bent toe), joint inflammation (synovitis), corns and pressure sores.
What is keyhole/minimally invasive bunion surgery, and how does it differ from traditional open surgery?
Keyhole, or minimally invasive bunion surgery, is a procedure which uses very small incisions to allow access to the bones for reshaping, straightening and pinning. The surgery is performed using specialised instruments, inserted through the small incisions, all under the guidance of an x-ray machine.
Traditional open surgery involves a large incision cutting through the layers of tissue, muscle and skin to reach the bone and correct the bunion.
In keyhole bunion surgery, normal foot alignment is achieved by stabilising the mid-foot joint and moving the bunion 100% away from the metatarsal, a procedure unachievable with traditional open bunion surgery. This results in reduced pain and a faster recovery.
Benefits of keyhole bunion surgery
Minimal scarring
With keyhole surgery, only tiny incisions of 2-5mm are used. There will still be scars, but just very small ones, which in the majority of patients are almost impossible to see after one year.
Reduced pain and faster recovery
Since only tiny incisions allow for access to the bones in minimally-invasive bunion surgery, there is no large wound. This reduces the risk of pain, stiffness and swelling after surgery which in turn improves recovery time allowing for a quicker return to normal activities.
Reduced recurrence rates
Keyhole bunion surgery, theoretically, has longer lasting benefits than some open surgery techniques for several technical reasons. One of these is that the keyhole technique locks out the first tarsometatarsal joint, which causes bunions, so that it cannot move any further.
