Hyperkyphosis is a type of foot deformity in which the abnormal increase in the longitudinal arch is the main change, and the height of the longitudinal arch is not restored even when the foot is in a fully weight-bearing state (Figure 1). The high arched foot is often combined with one or more other areas of the compound deformity. Most of these deformities require surgical intervention for clinical treatment. For young and mildly deformed patients, a preventive program can be developed through clinical evaluation to prevent or slow down the development of the deformity to improve symptoms. Qu Xintao, Department of Orthopedics, Jinan Military General Hospital (Figure 1) High arched foot can be classified according to the etiology: neuromuscular, congenital, acquired and idiopathic. Most high arched feet originate from neuromuscular diseases, including peroneal muscular dystrophy, poliomyelitis, spinal cerebellar tract degeneration, cerebral palsy, spinal muscular dystrophy, and spinal cord spinal herniation. These diseases often cause muscle imbalance in the lower leg and foot, resulting in compound deformities of the foot. Trauma and surgery are also common causes of high arched feet. For patients with high arched feet, treatment options can be divided into conservative and surgical treatment. The determination of the treatment plan relies heavily on a thorough examination and evaluation, which is often done by specialized hospitals and experienced physicians; leaving the deformity free to develop or treating it incorrectly often leads to progressive worsening of the deformity. In patients with high arched feet, the etiology, degree of deformity, and area involved in the deformity should be carefully evaluated to select an individualized treatment plan. For high arched feet caused by neuromuscular causes, treatment is a long-term process because it often develops progressively, and regular follow-up assessments are needed to adjust and improve the treatment plan; for high arched feet caused by traumatic or skeletal deformities, the deformity is already fixed and can often be completely corrected through one or several surgeries, but postoperative rehabilitation and prevention of recurrence need to be carried out under the guidance of a professional physician. Firstly, a detailed and complete medical history is very important to understand the condition and progress of the disease, and a thorough neurological examination is needed to clarify or exclude neurological diseases, including lower limb muscle strength, tendon reflexes, sensation, movement and neurophysiological characteristics, etc.; secondly, a clinical assessment is conducted, including assessment of the patient’s standing posture, foot and ankle shape, heel and toe walking Second, clinical assessment, including assessment of standing posture, foot and ankle shape, heel and toe walking, foot droop, plantar flexion limitation, foot rotation, ankle passive mobility, etc. In hospitals with conditions, gait analysis can be performed to clarify gait changes, and wood block test to determine the flexibility of hindfoot high arch and the relationship between anterior and posterior foot high arch; third, imaging examination, mainly including standard foot and ankle X-ray, weight-bearing front and lateral foot film and wood block film. For patients with severe skeletal changes, spiral CT and reconstruction are needed to understand the severity and extent of skeletal degeneration, and for patients who need to perform tendon displacement or soft tissue reconstruction surgery, MRI examination can be used to assess the soft tissue condition; finally, the design of treatment plan is based on the subjective will of the patient and the degree of expectation. 2.Pathogenesis of high arch foot High arch clubfoot is anatomically characterized by medial or medial metatarsal subluxation around the talus, hindfoot inversion, and internal rotation of the ankle and subtalar joint (internal rotation moment); the internal rotation force opposes the weak external rotation muscles and lateral ligaments of the ankle and subtalar joint, resulting in ankle instability; in the course of the disease, the non-concentric force of the ankle joint eventually leads to wear of the medial joint surface of the distal tibia and lateral The collateral ligaments are stretched and relaxed and eventually rupture. Soft tissue contractures or abnormalities aggravate the deformity progressively and prevent the correction of the bony deformity and the restoration of joint forces. In most adult patients, the skeleton has developed adaptive changes that are related to the degree of soft tissue contracture and weight-bearing walking. Continued disease progression will lead to spontaneous fusion of certain joints or degenerative changes secondary to contractures and abnormal forces. 3.Conservative treatment and health care of high arched foot For patients with high arched foot, conservative treatment and health care are basically the same, whether surgery or not, preoperative or postoperative, conservative treatment or health care are very important. The right approach can slow down the development of the deformity, improve the symptoms, and even gradually correct the deformity. Conservative treatment is mainly limited to young patients with limited deformity involvement, flexible deformity and no obvious bony changes, and is also used to promote recovery and maintain efficacy after surgical treatment. The main methods include orthopedic shoes, orthoses, braces and physical therapy. For patients aged 6 to 12 years, orthopedic shoes and night braces can be used to gradually correct the deformity according to the assessment. The results of this approach are better for patients with mild disease. If the deformity is caused by muscles and ligaments, the symptoms can be improved through reasonable exercises and physiotherapy, for example, patients with high gastrocnemius tone may lead to forefoot arch foot, so targeted gastrocnemius extension exercises can be carried out. For high arched feet due to traumatic causes, microsurgical techniques may be required depending on the situation, but the results are mostly poor, and eventually orthopedic foot surgery is required for further treatment. Conservative treatment can, to a certain extent, slow down the progression of the disease and improve the symptoms. However, the maintenance of efficacy varies from person to person, and the recurrence rate is high. According to our hospital’s treatment experience, long-term or irrational use of orthotics and braces can lead to muscle imbalance and progressive aggravation of deformity, even causing irreversible damage to tendons and joints. Therefore, conservative treatment or health care methods must be carried out under the guidance of experienced physicians, after regular conservative treatment is ineffective, or rigid high arched foot patients still need surgical intervention. 4.Surgical treatment of high arched foot Most of the high arched foot needs surgical treatment, and the surgical treatment plan varies from person to person, and a detailed assessment combined with the patient’s will is needed to draw up a specific treatment plan. Currently, the main surgical methods include: external fixation techniques, soft tissue surgery, osteotomy orthopedics and joint fusion, etc. Complex deformities sometimes require multiple treatments using a combination of procedures. Depending on the location and severity of the deformity, the available surgical procedures vary. The goals of surgery are to correct the deformity, to re-establish the balance of the muscles in the foot, to restore a metatarsal foot that can wear normal shoes, and to preserve as much joint function as possible if there is no secondary osteoarthritis. The principles of surgical treatment require not only correction of the existing deformity, but also resistance to its potential deformity and minimization of recurrence. The surgical treatment plan is based on the results of the preoperative evaluation and the subjective wishes of the patient. Flexible forefoot hypertelorism is corrected primarily by soft tissue release and tendon displacement, with good results in younger patients. In young (8-12 years old) patients with good forefoot and hindfoot flexibility, metatarsal fascia release combined with posterior tibial tendon transposition can better correct the deformity. Achilles tendon lengthening is required in patients with plantarflexion limitation in foot drop. Posterior tibial tendon transfer can avoid postoperative pronation and recurrence of forefoot rotation; peroneus longus transfer is mainly used to correct the first metatarsal plantarflexion and secondary hindfoot pronation deformity caused by compensatory strong peroneus longus muscle. In patients with rigid forefoot high arch deformity, midfoot osteotomy combined with soft tissue release and tendon transfer is currently used to correct the deformity. However, some of the procedures will shorten the dorsum of the foot, causing biomechanical changes to a certain extent, which will make the foot shorter, wider and thicker after surgery, and the appearance and function of the foot will be affected. It should be noted that secondary osteoarthritis can develop after any osteotomy due to joint surface damage, pseudarthrosis formation, joint shortening, and residual deformity. No procedure is absolutely adapted to every high arched foot deformity, depending on the severity and involvement of the patient’s deformity, and is best decided and performed by an experienced physician; inexperienced physicians have a higher failure rate and often result in irreversible damage to the foot, which affects future reconstruction. For correction of hindfoot deformities, if the deformity is flexible, the surgery may be limited to the forefoot. If it is stiff but without significant arthropathy, surgery is required to preserve the joint and restore the line of force, and heel osteotomy is feasible. In patients with stiff joints and severe lesions, arthrofusion needs to be considered. Joint fusion is mainly used for the correction of severe stiff hindfoot high arch deformity with joint degeneration or severe muscle imbalance. However, in recent years, this procedure is mostly used as a remedial procedure because it leaves functional limitations after surgery, limiting plantarflexion and dorsiflexion of the foot and ankle, and the functional activities of anterior and posterior rotation of the joint. High arched foot starts early, but progresses slowly. Preoperative diagnosis and evaluation are crucial for the determination of treatment plan and surgical approach. The key to determining the choice of treatment is the flexibility of the anatomy. Soft tissue surgery is the best option for patients who are young and have a flexible foot deformity. In contrast, bony surgery needs to be considered for patients with a fixed, rigid skeletal development. The pathogenesis of the deformity, its location, the degree of stiffness, and the need for postoperative tendon transfer to maintain the orthosis are all important factors in determining the prognosis. High arched foot is mostly a progressive developmental disease with complex and diverse etiology, often due to neuromuscular disorders. Treatment is a long-term process, and conservative treatment or health care can slow down the development of deformity and maintain postoperative efficacy.