What Is the Success Rate of Flat Foot Surgery?

Most people who undergo flatfoot surgery experience meaningful pain relief and improved function, though the specific numbers depend on which procedure is performed and how severe the deformity is. Across multiple studies, standardized foot and ankle scores roughly double from their preoperative values, and the majority of patients report satisfaction at follow-up periods ranging from a few years to over a decade. The picture gets more interesting when you look at the details: which procedures hold up best over time, what factors tip the odds in your favor, and what “success” actually means when the foot being corrected will never look or move exactly like one that was never flat.

How Success Is Measured

Surgeons and researchers rely on a few standardized scoring systems to track outcomes. The most common is the American Orthopedic Foot and Ankle Society (AOFAS) hindfoot score, which rates pain, function, and alignment on a scale where higher is better. Pain is often tracked separately on a visual analogue scale from 0 to 10. These scores give a consistent yardstick, but they do not capture everything a patient cares about. Whether you can hike again, wear normal shoes, or stand through a workday matters just as much as what a number on a chart says.

That said, the numbers are encouraging. In a study of young adults who had flatfoot surgery, the average AOFAS score climbed from about 48 preoperatively to 77 afterward, and pain scores dropped from roughly 6.5 out of 10 to about 3.¹ A long-term study of tendon transfer combined with calcaneal osteotomy reported even stronger gains: AOFAS scores went from about 48 to over 90, pain dropped from over 7 to about 1.3, and 87% of patients were pain-free and functioning well at final follow-up.² The variation between those two results reflects something real: outcomes depend heavily on which procedure fits the patient’s specific stage of flatfoot and how far the deformity has progressed.

Joint-Preserving Procedures and Their Track Record

For adults with a flexible flatfoot, meaning the arch can still be restored when you stand on your toes, surgeons strongly prefer operations that correct alignment without permanently fusing joints. The most studied combination is a tendon transfer (usually the flexor digitorum longus tendon is rerouted to replace the failing posterior tibial tendon) paired with a calcaneal osteotomy, where the heel bone is cut and shifted to realign the hindfoot. This pairing preserves most subtalar motion, which matters for walking on uneven surfaces, and allows patients to keep performing a single-leg toe rise, a functional benchmark that surgeons watch closely.³

One thing patients should know: improvement after these procedures is not instant. The research describes a prolonged period of steady gains in symptoms after surgery, and some people continue to feel better for a year or more.⁴ A related finding that surprises many patients is that the arch may look moderately improved on X-rays but not feel dramatically different when standing. The functional gains in pain and strength tend to outpace the visual changes in foot shape.

Lateral column lengthening is another common joint-preserving approach. It works by extending the outer side of the foot to swing the forefoot back into alignment. A meta-analysis of lateral column procedures found excellent clinical and radiological results across multiple studies, and radiographic evaluations confirm that these procedures correct the flatfoot deformity in three dimensions.⁵ ⁶ A modified version of this technique has also shown significant improvement in clinical outcome scores while reducing pressure on the soft tissues that maintain the arch.⁷

When Fusion Becomes Necessary

Once a flatfoot deformity becomes rigid, or the posterior tibial tendon has deteriorated past a certain point (typically stage III or IV), joint-preserving surgery can no longer correct the problem. Surgeons then turn to arthrodesis, which permanently fuses one or more joints in the hindfoot. The trade-off is clear: you lose some range of motion, but you gain a stable, corrected foot that can bear weight without pain.

The traditional approach has been triple arthrodesis, which fuses three joints in the back of the foot. But a body of research now supports double arthrodesis, fusing only two joints, as an equally effective alternative. A systematic review found that fusion rates were nearly identical: about 92% for both double and triple arthrodesis, with similar time to bony union.⁸ A prospective comparison confirmed no significant differences in AOFAS scores or radiographic correction between the two groups, with both showing marked improvement from preoperative levels.⁹

The advantage of double arthrodesis is what it avoids. Triple arthrodesis carries risks of longer operating times, lateral wound complications, residual deformity, and accelerated arthritis in nearby joints.¹⁰ When outcomes are comparable, less is generally better. Separately, combining talonavicular arthrodesis with a calcaneal shift osteotomy, which preserves the subtalar joint entirely, has been shown to produce results equivalent to double arthrodesis in both clinical scores and X-ray measurements.¹¹ This trend toward less invasive fusion options is one of the more encouraging developments in the field.

Subtalar Implants and the Question of Removal

Subtalar arthroereisis uses a small implant placed in the sinus tarsi, the natural space between the ankle bone and heel bone, to block excessive inward rolling. It is popular in both children and adults because it avoids cutting bone or fusing joints. The catch is that the implant sometimes needs to come out.

In a prospective study of 100 adults who received subtalar implants, the overall removal rate was about 22%. Patient age did not affect the likelihood of removal, but implant size did: the largest size (11 mm) was removed significantly more often than smaller ones.¹² Removal itself is a relatively minor procedure, and the correction achieved tends to be maintained afterward. In children, a different pattern emerges: implants are often planned for temporary use. One pediatric study found that about 86% of patients had their screws removed after an average of about two years, with no difference in functional outcomes between those who kept the hardware and those who had it taken out.¹³

What Affects Your Odds

Two patient factors dominate the research on flatfoot surgery outcomes: smoking and body weight. Smoking is by far the bigger concern. In hind- and midfoot fusion procedures, current smokers had a nonunion rate nearly six times higher than nonsmokers, along with elevated infection rates and greater need for bone stimulators to encourage healing.¹⁴ Heavier smoking within that group was associated with even slower union. A separate study found zero nonunions in midfoot arthrodesis patients when smokers and those with nerve-related foot disease were excluded, underscoring how powerfully these risk factors shape outcomes.¹⁵ The encouraging news for former smokers: ex-smokers in the same study had nonunion rates statistically indistinguishable from people who never smoked.¹⁶

Obesity, by contrast, turns out to be less of a problem than many patients fear. A study that divided flatfoot reconstruction patients into three body mass index categories found no differences in any postoperative outcomes assessed, including radiographic correction, pain, and function.¹⁷ That does not mean weight is irrelevant to foot health in general, but it suggests that higher body weight alone should not disqualify someone from surgery or lead them to expect a worse result. One study of lateral column lengthening did find that lower BMI predicted better functional activity scores afterward, so the relationship is not entirely absent, just less dramatic than the effect of smoking.¹⁸

Recovery and Getting Back to Activity

Flatfoot reconstruction involves a longer recovery than many people anticipate. You will typically spend the first several weeks in a cast or boot and off your feet entirely, then progress to protected weight-bearing, then gradually return to normal activities. Research tracking the timeline found that most patients returned to some level of physical activity at a median of 6 to 9 months, but reaching their maximum preoperative activity level took a median of 13 to 18 months.¹⁹ A separate publication from the same research group reported slightly later participation windows of 9 to 12 months, with 12 to 18 months to reach peak levels, suggesting individual variation around those medians is real.²⁰

What stands out in these return-to-activity numbers is that people generally do get back to being active. Among the patients tracked, only about 3% were sedentary at follow-up, while roughly a third were classified as extremely active and another quarter as highly active.²¹ These are not young athletes returning from a sports injury; many are middle-aged adults with degenerative tendon disease who had significant limitations before surgery. The fact that the overwhelming majority returned to moderate or high activity levels speaks to the functional effectiveness of reconstruction, even if the road back is measured in seasons rather than weeks.

Reoperation Rates and Long-Term Durability

A question that matters a great deal but is rarely front and center in patient discussions: how often does the surgery need to be redone or revised? A large retrospective study following 321 consecutive flatfoot reconstructions over 14 years found that about 17% of patients needed additional surgery.²² The reasons break down in a way that is useful to understand. The most common reason, accounting for well over half of reoperations, was painful hardware in the heel bone, which typically means removing a screw rather than redoing the reconstruction. Conversion to a triple arthrodesis, meaning the initial softer procedure did not hold and a fusion was eventually needed, accounted for a smaller share. Wound healing complications rounded out the list.²³

When you look at complication profiles for specific procedures, the numbers are generally manageable. A study of corrective osteotomies using porous titanium wedges reported no major complications or implant failure. Minor issues included hardware pain in about 8% of patients and a 5% rate of transfer pain from the wedges.²⁴ The overall picture is that flatfoot surgery is durable for the large majority, but a notable minority will end up back in the operating room for a secondary procedure, most often something smaller than the original operation.

Flatfoot Surgery in Children

Pediatric flatfoot is a different clinical situation from the adult version. Most children with flexible flat feet never need surgery; their arches develop over time or the condition remains painless. When surgery is warranted, usually for persistent pain that has not responded to orthotics and physical therapy, the approaches differ from adult procedures and the outcomes are studied over especially long follow-up periods because the patients have decades of life ahead.

A systematic review of surgical treatment for symptomatic pediatric flexible flat feet concluded that surgery produces satisfactory long-term clinical and radiological outcomes with a manageable complication profile.²⁵ One of the best long-term datasets comes from a study that followed children who had subtalar arthroereisis for an average of 15 years. At final follow-up, the mean AOFAS score was about 90 out of 100, more than 70% had normal footprints and proper hindfoot alignment, and about 88% of patients were satisfied with the procedure.²⁶ Those results are remarkable for their duration; a correction that still looks and functions well 15 years later, through the growth spurts and activity demands of adolescence and young adulthood, is as close to a long-term success story as orthopedic surgery produces.

Advances in Preoperative Planning

One area of active development is the use of weight-bearing CT scans combined with three-dimensional reconstruction for surgical planning. Traditional X-rays are two-dimensional and taken while standing, which gives useful but incomplete information about a three-dimensional deformity. Newer imaging allows surgeons to visualize the exact geometry of the problem before making an incision.

A prospective study in pediatric patients found that preoperative 3D planning was consistent with the actual imaging findings at both 3-month and 18-month follow-up, with no significant differences between the planned and achieved measurements for key angles and dimensions.²⁷ In practical terms, that means the surgeon could predict preoperatively what the foot would look like postoperatively and hit those targets reliably. This kind of precision matters especially for implant-based procedures, where choosing the wrong size can mean a second surgery for removal, as the adult arthroereisis data showed.

Minimally invasive techniques are also gaining ground. A study of double calcaneal osteotomy performed through small incisions reported full radiological and clinical union at 12 weeks in all patients, with no sural nerve injuries, wound breakdowns, or infections from the minimally invasive incision sites.²⁸ Smaller incisions do not automatically mean smaller corrections; the average shift achieved was about 8 mm, and the average improvement in the key alignment angle was about 15 degrees, both substantial corrections. These techniques are still surgeon-dependent and not available everywhere, but they point toward a future where the recovery burden may shrink even as correction quality stays high.