HyProCure is a minimally invasive surgical option for selected patients with symptomatic flat feet (pes planus), aimed at correcting pathological talotarsal joint motion rather than simply supporting the arch externally. It involves placing a titanium stent into the sinus tarsi to stabilise the subtalar joint, with the goal of improving alignment, reducing pain, and enhancing function while preserving joint motion.
Pathomechanics of flat feet and treatment rationale
Symptomatic flat feet are often associated with excessive or prolonged pronation driven by instability at the subtalar or talotarsal joint rather than just “low arches” in isolation. When the talus excessively plantarflexes and adducts on the calcaneus, the medial longitudinal arch collapses, the heel everts, and the forefoot abducts, altering the kinetic chain through the foot, ankle, knee, hip, and lower back. This can contribute to plantar fasciopathy, posterior tibial tendon overload, medial knee stress, and compensatory proximal symptoms, even though many flat feet remain asymptomatic.
Conservative management—such as custom orthoses, physical therapy, and footwear modification—aims to control pronation and redistribute load but does not change the underlying joint structure. For patients who remain symptomatic despite appropriate conservative care, surgical options range from osteotomies and tendon procedures to subtalar arthroereisis, of which HyProCure is a specific extra‑osseous talotarsal stabilisation (EOTTS) system.
Surgical technique and mechanism of action
HyProCure uses a small, threaded titanium stent inserted into the sinus tarsi, the naturally occurring canal between talus and calcaneus, via a small incision on the lateral aspect of the foot. The device sits extra‑osseously in this space, so there is no drilling or cutting of bone, and the surrounding joint surfaces remain intact. Functionally, the implant acts like a “doorstop” to excessive subtalar motion, limiting the pathologic pronatory excursion that allows the talus to collapse medially and the arch to flatten, while still permitting physiological inversion–eversion.
Once placed, the stent immediately realigns and stabilises the hindfoot, bringing the talus back over the calcaneus and improving the orientation of the ankle and midfoot. This restores a more normal heel‑to‑toe progression, improves the timing and magnitude of pronation–supination during gait, and can rebalance ground reaction forces through the medial and lateral columns. Because bone is not cut, the surgery is typically performed as a day procedure, often under local or regional anaesthesia, and the implant is designed as a long‑term or permanent solution but can be removed if necessary.
Indications, patient selection, and postoperative course
HyProCure is generally considered for patients with flexible, symptomatic pes planus or overpronation in whom conservative measures have failed, including both children and adults. In paediatric patients, it is often positioned as an intermediate option when orthoses are insufficient yet full reconstructive surgery would be disproportionately invasive. Adults with chronic pain in the feet, ankles, knees, or lower back related to talotarsal malalignment may also benefit, provided that the deformity is flexible and there is no advanced degenerative joint disease or rigid flatfoot.
Postoperatively, protocols vary, but patients typically weightbear in a protective boot shortly after surgery, transitioning to normal shoes within weeks as swelling resolves and gait adapts. There is usually a short period of altered walking as the neuromuscular system adjusts to the corrected alignment, with full adaptation commonly reported over the first year. Many patients experience improved tolerance for walking, running, and jumping as load distribution normalises and painful overuse of soft tissues reduces.
Outcomes and benefits
Published clinical and industry-reported data suggest high success and satisfaction rates with HyProCure for flatfoot deformity and talotarsal instability. Reports describe approximately 94–95 percent success in achieving durable correction and symptom relief, with over 97 percent of patients rating outcomes as good or excellent at around one year post‑procedure. The realignment of the subtalar joint reduces abnormal stresses not only in the foot but along the kinetic chain, and many patients report reductions in pain at the knees, hips, and lower back together with improved mobility and quality of life.
An important advantage is that HyProCure aims to treat the underlying structural cause of hyperpronation rather than compensating for it with external devices, potentially removing or reducing the need for long‑term orthotic use. The procedure preserves joint motion, avoids bone cuts, and is considered minimally invasive, which may lead to shorter operative times, less soft tissue disruption, and quicker recovery compared with traditional osteotomies. Furthermore, the implant is removable, and removal does not necessarily lead to loss of all correction, offering a degree of reversibility if complications or intolerance occur.
Risks, complications, and limitations
Despite these benefits, HyProCure is not without risk, and complication rates differ markedly between children and adults. In a 2024 clinical study on flatfoot patients in China, overall complication incidence was reported at about 10.6 percent, but only 5.1 percent in children and adolescents compared with 28.8 percent in adults. Documented complications include sinus tarsi pain, peroneal muscle spasm, increased tension in the Achilles–triceps surae complex, and reduced muscle strength, sometimes necessitating implant removal.
The same study reported overall implant removal rates of about 4.4 percent, with just over 1 percent in children and approximately 15 percent in adults, underscoring the higher risk profile in mature, stiffer feet. Persistent sinus tarsi pain is a leading indication for removal and may relate to device size, positioning, or patient-specific anatomy. Flat feet themselves are often asymptomatic, so careful selection is essential to ensure that the patient’s symptoms actually arise from talotarsal malalignment and not from other pathologies; otherwise, expectations may not be met despite technically successful surgery.
HyProCure is also limited in rigid deformities, advanced arthritis, or cases where significant soft tissue reconstruction or bony realignment is required, in which case osteotomies or fusions may be more appropriate. As with any implant-based procedure, long‑term outcomes depend on factors such as body weight, activity level, neuromuscular control, and adherence to rehabilitation, and there is still ongoing research to refine patient selection criteria and implant sizing strategies.
Taken together, HyProCure represents a targeted subtalar arthroereisis option that can offer meaningful structural correction and symptom relief for well‑selected patients with flexible, symptomatic flat feet who have not responded to conservative therapy. For clinicians, it occupies a niche between orthotic management and more invasive reconstructive surgery, with the advantages of a minimally invasive approach and reversible implant, but it requires thoughtful assessment of biomechanics, comorbidities, and patient expectations to optimise outcomes and minimise complications, particularly in adults.