Foot surgery for overpronation? (bone graft / sinus tarsi implant)?

Question

I am 16 and I have really badly overpronating feet (collapsed arches, falling inward). It has caused me much pain from tendonitis in the overworked tendons which eventually led to a wheelchair for several days... anyways, my foot surgeon is reccomending a bone graft surgery that will strengthen my foot and prevent outward motion of the front of the foot so that my arches will no longer collapse. I might also get an "implant" (which is basically like a bolt) which I believe they will place in between my sinus tarsi bones ... (the bolt depends on what my foot looks like to the surgeon as it is splayed open on the table).

Has anybody had this surgery or this foot condition or knows about it? Any advice / tips / insight would be great because I am probably going to have it in a couple months ... thanks!

Answer 1

Introduction

The podiatric surgeon is taught to approach foot surgery by keeping the knowledge of normal foot function and biomechanics in mind. Because of the weightbearing nature of the foot, surgical procedures must be designed to be as stable as possible to withstand the forces of everyday standing and walking. Care is taken to understand the cause of the problem so as to provide a long-lasting cure, when possible. Greater than 99% of podiatric surgery is done in an outpatient setting such as a hospital outpatient department, a freestanding surgery center or in the podiatry office. Most procedures allow for immediate walking with a surgical sandal. Some procedures may require the use of a cane, crutches, or a cast. Specific surgical treatments for many common (and some less common) foot conditions will be discussed.

Surgery for flat feet is generally reserved for the most symptomatic cases. Orthotics are often the first line course of treatment. Many people have what are referred to as "Flat Feet" but are relatively asymptomatic. Flat feet may result in significant foot pain and deformity because of excessive pronation which causes joint instability. Flat foot procedures are designed to provide for a more stable foot which pronates less. Most flat foot surgery is performed on patients in the adolescent age group. There are a large variety of specific surgical procedures that may be used. They may be grouped according to the region of the foot that is treated. Often, 2 or 3 procedures may be performed together from the different groups.

Rearfoot osteotomies

These are procedures which are designed to change the position of the heel into an inverted or supinated position (the opposite of everted and pronated which are found in flat feet.) An osteotomy is a surgical cut in the bone. Often, a wedge of bone is removed to change the angle of the heel bone (calcaneus).  Other procedures are transpositional and involve sliding of one part of the bone along the other part of the bone. (E.g. the Koutsogianis procedure). Other procedures involve adding a bone graft and opening the wedge to change the angle of the calcaneus.( E.g. the Evans Procedure). These osteotomies are generally held together with special screws, pins or bone staples and require a period of casting and immobilization for several weeks.

Medial column stabilizations

These procedures involve fusing two or more of the bones along the medial side (inner side) of the foot. Common fusion sites are the navicular and medial cuneiform.  These bones have often dropped in a flat foot and fusing them provides more stability. These osteotomies are generally held together with special screws, pins or bone staples and require a period of casting and immobilization for several weeks.

Tendon transfers

Sometimes the insertion sites of tendons are detached and then reattached to bones at different locations. The result is a dynamic stabilization. Repositioning of the tendons allows the muscles that pull them to exert their force in a more beneficial way to help support the arch. The Young tenosuspension procedure reattaches the Tibialis Anterior tendon to a better position beneath the medial arch where it can pull up on the arch to support it.

Tendon lengthening

Often, the Achilles tendon is tight and is a major deforming force contributing to flat foot conditions. A condition associated with a tight Achilles tendon is known as equinus. An Achilles tendon lengthening procedure is often effective at reducing this deforming force. The calf is made up of 2 gastrocnemius muscle bellies as well as the soleus muscle. The Achilles tendon attaches to all three. An Achilles tendon lengthening lengthens the whole group together. Sometimes, the gastrocnemius muscles are tight while the soleus is not. In this case, a gastrocnemius recession can be performed to lengthen only the gastrocnemius while leaving the soleus alone.

Arthroeresis

These are procedures in which a peg made of plastic or titanium is placed in front of a bone to limit its motion. A common location for placement of such a device is the Sinus Tarsi which is a cone-shaped space between the talus and calcaneus bones. The peg helps to limit pronation. This is often just a temporary measure with the peg left in for a few years and then removed.

Arthrodeses

An arthrodesis is a fusion of two bones. In addition to the medial column stabilization fusions discussed above, rearfoot bones may also be fused. Rearfoot fusions are generally reserved for the most severely deformed, arthritic and painful feet . A Triple Arthrodesis is a fusion of the Talo-calcaneal, Talo-navicular and Calcaneo-cuboid joints. This is one of the most complex foot surgeries performed since all three joints must be aligned and fused properly to achieve a satisfactory result. In addition, because motion in the rearfoot is eliminated, the ankle joint and other joints in the foot may be forced into compensating to provide additional motion which could result in future symptoms in those places. These fusions are generally held together with special screws, pins or bone staples and require a period of casting and immobilization for two or three months.

More on Flat Feet-  Common Foot Problems page

  High Arched Feet (Pes Cavus)

Surgery for high arched (cavus) feet is generally reserved for the most symptomatic cases. Cavus feet may result in significant foot pain and deformity. These feet are often rigid and will not flatten at all. The lack of shock absorption associated with these rigid feet may result in symptoms of the knees, hips and back as well as the foot. In addition to the high arch, the foot is often positioned in an inverted position that may be prone to ankle sprains. This is a common reason for pursuing this type of surgery.   .

Rearfoot osteotomies

These are procedures which are designed to change the position of the heel into an everted or more pronated position (the opposite of inverted and supinated) An osteotomy is a surgical cut in the bone. Often, a wedge of bone is removed to change the angle of the heel bone (calcaneus).  A common procedure is called the Dwyer osteotomy. A pie-shaped wedge of bone is removed from the lateral side (outer side) of the calcaneus and as the bottom portion of the heel bone is closed along the hinge that is created, the heel is rotated into a straighter position. These feet are also prone to chronic ankle sprains. The Dwyer procedure may be performed along with a lateral ankle stabilization procedure to prevent future ankle sprains. These osteotomies are generally held together with special screws, pins or bone staples and require a period of casting and immobilization for several weeks.

1st Metatarsal Osteotomies

There is often a 1st metatarsal deformity associated with the rearfoot deformity. The 1st metatarsal bone is often plantar declinated (positioned so that it sits downward and protrudes at the ball of the foot relative to the other metatarsal bone). To correct this, a wedge of bone may be removed from the top of the 1st metatarsal to correct its position. This may also be held together with special screws, pins or bone staples and require a period of casting and immobilization for several weeks.

Midfoot osteotomies

These are procedures in which wedges of bone are removed across the entire middle of the foot to reduce the high arch. These procedures  are not performed as commonly as the other procedures. They require extensive rehabilitation postoperatively.

Tendon transfers

Sometimes the insertion sites of tendons are detached and then reattached to bones at different locations. The result is a dynamic stabilization. Repositioning of the tendons allows the muscles that pull them to exert their force in a more beneficial way to help support the arch. The Jones tenosuspension procedure reattaches the Extensor Hallucis longus tendon to the 1st metatarsal where it can pull up on  it. Another procedure is the SPLATT (Split Tibialis Anterior Tendon Transfer) which redirects part of the tendon to the lateral (outer) side of the foot so that the tendon may help to evert rather than invert the foot.

More on Cavus Feet- Common Foot Problems page

Morton's Neuroma

Excision of a neuroma is a fairly straightforward and simple procedure. These are commonly approached from the top of the foot with an incision  usually measuring less than 1 1/2 inches just behind the space between the 3rd and 4th toes (or sometimes between the 2nd and 3rd toes). The enlarged nerve is identified and separated from the surrounding structures. A section of the nerve is removed and the wound is closed with a few stitches. There are no muscles controlled by the nerve so most people can live comfortably without it. There is often a small area of numbness between the 2 toes but it is usually not something that is noticeable unless it is specifically tested. There is a chance that the neuroma could reoccur or that the 'stump' of the remaining nerve could be painful but most people do well following the procedure. Most people are able to walk immediately following the surgery. Patients commonly wear a surgical shoe for about 3 weeks. Some surgeons may prefer to approach the nerve through an incision on the bottom of the foot but this may require a period of non-weightbearing after the surgery.

Tarsal Tunnel Syndrome

Tarsal tunnel surgery is usually performed to reduce pressure on the Tibial nerve as it travels below the medial malleolus (ankle bone on the inner side of the foot). A curved incision is usually made and after releasing the ligament that sits over the nerve (flexor retinaculum). Occasionally, there may be an abnormal mass (e.g. an enlarged vein, a cyst or a benign tumor) sitting near the nerve. Any abnormal mass is removed to reduce pressure on the nerve. Additionally, if the nerve is being entrapped by a muscle (e.g. Abductor Hallucis)