Flat Foot
The flat foot is a commonly encountered deformity characterized by the collapse of the arch of the foot, affecting posture and daily comfort. This condition can lead to various pains and discomforts
What Is Flat Foot?
A flat foot is a foot with a poorly defined arch, with increased support at the level of the medial arch of the foot. Unlike a so-called "normal" foot, where the internal arch forms a pronounced curve that does not touch the ground, a flat foot is characterized by a partial or complete collapse of this arch, resulting in a larger surface area in contact with the ground.
Flat foot is an anatomical variation that can be present from childhood or develop in adulthood. It is important to distinguish the physiological flat foot, which simply corresponds to a particular morphology without any pathological consequences, from symptomatic or decompensated flat foot, which causes pain and functional limitations.
What are the causes of Flat Foot?
Flat foot is most often constitutional. It is an anatomical variation of the foot. Therefore, flat foot is not in itself a pathological condition. Flat foot can be post-traumatic, particularly after injuries to the Spring ligament and the posterior tibial tendon.
There is a specific case after displaced articular fractures of the calcaneus. The clinical presentation is that of a pseudo valgus flat foot, which clinically appears to be a flat foot on clinical examination, with varus of the large tuberosity of the calcaneus on imaging.
What are the symptoms of flat feet?
The symptoms of flat feet can vary depending on the severity of the condition. Here are the main signs:
- Pain in the arch of the foot, heel, ankle, or inner side of the foot
- Fatigue in the feet, especially after standing for a long time or walking
- Swelling along the inner side of the ankle
- Pain along the path of the posterior tibial tendon (inner side of the ankle)
- Abnormal shoe wear (usually on the inner side)
What are the complications and associated conditions of flat feet?
Lowering of the plantar arch is not only an aesthetic or comfort problem: it induces a cascade of abnormal stresses on the surrounding anatomical structures. This deformation may also be associated with other foot pathologies such as humpback tarsus, creating a complex clinical picture that requires specialized management.
Understanding the complications associated with flatfoot is essential to grasp the complexity of this pathology and the need for appropriate care. The main complications include:
The posterior tibial muscle and tendon are particularly stressed in the case of flatfoot since the role of this muscle and its tendon is to partially support the medial plantar arch. When the plantar arch collapses, significant tension occurs in the tendon, which can lead to its inflammation, injury, or even rupture.
There is a strong ligament called the "Spring ligament" which serves to medially lock the talus head, and thus the talo-navicular joint. This ligament is located medially with a plantar extension; it also helps prevent the head of the talus from escaping downward, which could worsen the flatfoot deformity.
Injury to this ligament is common in cases of flatfoot, especially when decompensated. Clinical examination may then reveal increased abduction of the midfoot compared to the healthy side, indicating talo-navicular uncovering and thus talo-navicular laxity.
The lateral tilt of the hindfoot on the outer side, in valgus, can increase pressure on the lateral side of the ankle, causing inflammation in the anterolateral groove. There is pain during dorsiflexion and plantar flexion in cases of soft anterior impingement. Pressure on the lateral groove is what causes the pain.
The valgus tilt of the hindfoot increases valgus stresses on the subtalar joint, located below the ankle. There may be pain in the tarsal sinus due to subtalar instability, or from compression of the fat present in the tarsal sinus, which can become inflamed.
The fibular tendons, also called peroneal tendons, run along the posterior surface of the lateral malleolus, or fibula, then pass under the tip of the lateral malleolus before inserting on the styloid process of the fifth metatarsal for the short peroneal and on the plantar base of the first cuneiform of the first metatarsal for the long peroneal.
In the event of a valgus hindfoot, the tendons may become trapped between the tip of the fibula and the lateral wall of the calcaneus, causing what is known as external sub-malleolar impingement. Pressure on the tendons beneath the tip of the fibula is then very painful.
Clinical examination very often reveals contracture of the Achilles tendon, or the calf muscles (gastrocnemius), when manually correcting the hindfoot axis. This contracture is both a cause and a consequence of flatfoot, creating a true vicious cycle. When the Achilles tendon is contracted, it limits ankle dorsiflexion, forcing the foot to compensate by collapsing further at the plantar arch during walking, thereby worsening the deformity.
This limitation of mobility manifests as the inability to flex the foot beyond a certain angle, especially when the knee is extended, and constitutes a determining factor in the therapeutic strategy, requiring specific stretching exercises or, in severe cases, a surgical elongation procedure.
Why choose La Clinique du Pied?
The Foot Clinic brings together a multidisciplinary team specialized in the care of foot and ankle disorders, offering in-depth expertise in the diagnosis and treatment of flat feet. Thanks to a modern technical platform enabling a complete biomechanical assessment and advanced imaging examinations, our specialists provide an accurate evaluation of your condition in order to offer a personalized treatment tailored to your situation.
Which shoes or insoles to relieve Flat Feet?
A painless flat foot does not require insoles or special shoes. A symptomatic flat foot can be relieved by wearing high shoes with rigid uppers, as they provide stability to the rear and midfoot.
Orthopedic insoles may be offered as part of the medical treatment of flat foot, mainly in cases of reducible, flexible flat foot with a competent posterior tibial muscle. Footwear and insoles complement the functional treatment of flat foot, which consists of strengthening the intrinsic muscles of the foot, the posterior tibial muscle, and stretching the posterior muscular chains.
Which procedures are used to treat Flat Feet?
There are several types of surgical procedures to correct flatfoot. The type of surgery depends on the severity of the flatfoot, its reducibility, the presence of a competent posterior tibial muscle, and any associated osteoarthritis. It is also important to take into account the patient's history, the presence of chronic inflammatory disease, and tissue quality.
- Achilles tendon lengthening: Allows correction of tendon contracture and improves ankle dorsiflexion.
- Posterior tibial tendon reconstruction: Repair or tendon transfer to restore support to the arch of the foot.
- Ligament plication: Tightening of stretched ligaments, especially the Spring ligament.
- Medializing calcaneal osteotomy: Shifting the heel inward to correct hindfoot valgus.
- Lateral column lengthening osteotomy (or Evans osteotomy): Inserting a bone graft to lengthen the outer side of the foot and reduce abduction.
- First cuneiform osteotomy: Correction of the elevation of the first ray (Cotton osteotomy).
Osteotomy represents a fundamental surgical technique in the reconstruction of flatfoot, allowing realignment of the foot bones to restore a more physiological anatomical architecture. These bone procedures are particularly indicated when the deformity is rigid or semi-rigid, requiring structural correction to restore function.
- Subtalar arthrodesis: Fusion of the joint below the ankle to stabilize the hindfoot.
- Talonavicular arthrodesis: Fusion to correct deformity at the midfoot level.
- Triple arthrodesis: Fusion of three hindfoot joints, reserved for the most severe cases.
Foot arthrodesis techniques are the last-resort treatment for severe flatfoot with advanced osteoarthritis or irreducible deformities.
How does flatfoot reconstruction work?
Before the procedure, the surgeon conducts a full assessment including a detailed clinical examination, weight-bearing X-rays (standing), and sometimes a CT scan or MRI to evaluate the condition of the tendons and ligaments. The necessary surgical procedures are determined based on the severity and reducibility of the deformity. The operation is carried out under general or regional anesthesia (epidural) and usually lasts between 1.5 and 3 hours depending on the complexity.
The surgeon often combines several procedures such as lengthening the Achilles tendon if necessary, calcaneal osteotomy to reposition the heel, reconstruction of the posterior tibial tendon by repair or transfer, lateral lengthening osteotomy to correct abduction, as well as procedures on the midfoot if needed such as cuneiform osteotomy.
Surgical reconstruction of flatfoot requires specific expertise in foot anatomy and biomechanics to effectively restore the complex architecture of the plantar arch. The preoperative evaluation may include a diagnostic arthroscopy to directly visualize the condition of the cartilages and intra-articular structures, allowing the surgical strategy to be precisely adapted.
FAQ
There is no particular shoe brand especially recommended for symptomatic flat feet. Wearing shoes with rigid uppers helps stabilize flat feet and relieve pain.
Some over-the-counter insoles are dedicated to flat feet. Custom orthopedic insoles made by a podiatrist allow for personalized and therefore more effective correction of flat feet.