Skip to content

Foot Deformities

Foot deformity evaluation & management: congenital (clubfoot), acquired (flatfoot, cavus), and common pathologies (hallux valgus) approaches.

Overview

Nonsurgical treatment serves as the initial choice for almost all congenital foot deformities, with surgical intervention generally reserved for patients in whom conservative measures fail to relieve symptoms or improve function [5]. For specific conditions, surgical indications are precise: flexible adult acquired flatfoot deformity requires early diagnosis to initiate treatment while the deformity remains mild and flexible, given the controversy surrounding optimal surgical techniques [3]. Similarly, surgical management for coxa vara in childhood is indicated for progressive, painful, unilateral deformity or leg-length discrepancy, whereas moderate nonprogressive deformity often does not require surgery [28].

Surgical goals and outcomes vary by pathology. For spastic equinovarus foot deformity, indications focus on obtaining a balanced, braceable, functional lower extremity with a plantigrade foot [14]. In pediatric persistent deformities, talectomy remains an effective procedure despite associated complications [8]. For severe pes planovalgus, complex reconstruction including distraction arthrodesis of the calcaneocuboid joint and stabilization/transfer of the flexor digitorum longus tendon accounts for satisfactory outcomes via pain relief and restoration of function [6]. Tarsal V-osteotomy for pes cavus permits correction at the most prominent point without the disadvantages of classic techniques [15].

Specific corrective procedures demonstrate high efficacy when appropriately selected. The Ponseti Method for untreated clubfeet in Nepalese patients aged one to five years achieved a plantigrade foot in 95% of cases initially, with maintenance in most patients despite common residual deformities [1]. Surgical treatment for hallux valgus must be adapted to the type and severity of the deformity, with success rates ranging from 80% to 95% [23]. The sling procedure for correction of splay foot, metatarsus primus varus, and hallux valgus has continued to be satisfactory with maintained correction in patients adhering to after-care [9]. However, late complications such as residual deformity and metatarsalgia are the primary causes of unsatisfactory outcomes in distal first metatarsal displacement osteotomy [4]. For Morton’s neuroma, the plantar approach is recommended if the patient needs a better appearance, as it had less influence on quality of life regarding foot appearance compared to the dorsal approach [31].

Anatomy & Pathophysiology

General Biomechanics and Classification

Accurate evaluation of foot deformities requires a thorough understanding of foot anatomy and biomechanics [11]. The Rotterdam Foot Classification system categorizes anatomic features of the foot into four distinct categories [10]. Assessing multi-joint interactions in progressive collapsing foot deformity aids in understanding its pathophysiology [2]. Flexible adult acquired flatfoot deformity involves pathophysiological mechanisms that necessitate early diagnosis while the deformity remains mild and flexible [3].

Hallux Valgus Pathophysiology

Hallux valgus is a complex deformity influenced by extrinsic factors, such as constricting footwear, and intrinsic factors, including heredity and foot mechanics [52]. Hallux valgus deformity and its severity are positively associated with the magnitude of anteroposterior postural sway [72]. During the weight-loading process, the first metatarsal-cuneiform joint turns dorsiflexed, supinated, and internally rotated [64].

Plantar Aponeurosis Strain

A wedge under the lateral aspect of the forefoot decreases strain in the plantar aponeurosis [65]. Conversely, a wedge under the medial aspect of the forefoot increases strain in the plantar aponeurosis [65].

Classification

Ponseti Method: In Nepalese patients aged one to five years with untreated clubfeet, this method achieved a plantigrade foot in 95% of cases initially [1]. However, residual deformities remained common despite the maintenance of initial plantigrade alignment in most patients [1].

Progressive Collapsing Foot Deformity (PCFD): Assessing multi-joint interactions aids in understanding pathophysiology and surgical treatment planning [2]. The new PCFD classification system offers an option to approach this complex three-dimensional deformity and individualize treatment for each patient's unique anatomy [49].

Flexible Adult Acquired Flatfoot: Classification of this deformity emphasizes the need for early diagnosis to initiate treatment while the condition remains mild and flexible [3].

Rotterdam Foot Classification: This system contains four categories of anatomic features of the foot [10].

AOFAS-Hallux-MTP-IP: The American Orthopaedic Foot and Ankle Society hallux metatarsophalangeal-interphalangeal scale is recommended for the comprehensive assessment of clinical conditions in patients with hallux valgus deformity in Mainland China [55].

Clubfoot Management: The degree of deformity must be evaluated clinically and radiographically to select proper management, with the most important consideration being the restoration of normal anatomy while avoiding overcorrection [12]. Clubfoot is not a single entity requiring uniform treatment; surgical methods must be selected based on a clear understanding of the specific anatomical and functional derangement in each foot [20].

Other Considerations: Nonsurgical treatment is the initial choice for almost all congenital foot deformities, with surgical treatment generally reserved for cases where nonsurgical measures fail to relieve symptoms or improve function [5]. Recurrent bilateral mid-tarsal subluxations affecting both feet similarly indicate an underlying structural abnormality [7]. Foot fractures and dislocations require an understanding of classifications and management to ensure anatomic alignment and functional recovery [48]. Macrodactyly of the foot is a rare congenital malformation with diverse clinical manifestations and multiple elements' involvement [17]. One in every ten school-aged children in Southern Ethiopia had a flat foot [18]. The chapter on pediatric lower extremity deformities provides an overview of assessment, classification, and treatment algorithms for limb-length discrepancy, angular deformities like Blount disease, rotational deformities, and limb deficiencies [46].

Clinical Presentation

Congenital foot deformities typically present with diverse clinical manifestations and multiple elements' involvement, such as in macrodactyly [17]. Nonsurgical treatment is the initial choice for almost all congenital foot deformities [5]. Surgical treatment is generally reserved for patients in whom nonsurgical measures fail to relieve symptoms or improve function [5].

In untreated clubfeet, a plantigrade foot was achieved in 95% of Nepalese patients seen between ages one and five and followed for at least 10 years [1]. However, residual deformities are common in untreated clubfeet even when a plantigrade foot is initially achieved [1]. Club feet vary in severity, requiring clinical and radiographic evaluation to select proper management [12]. The most important consideration in clubfoot management is the restoration of normal anatomy while avoiding overcorrection [12]. Club foot is not a single entity requiring uniform treatment; surgical methods must be selected based on specific anatomical and functional derangement [20].

Adult acquired flatfoot deformity presents with complex morphometric changes involving multi-joint interactions [2]. Flexible adult acquired flatfoot deformity requires early diagnosis to initiate treatment while the deformity is mild and flexible [3]. Rigid flatfoot deformities in adolescents have a less predictable clinical course and are associated with various underlying causes [16]. Investigation of the etiology is critical for rigid flatfoot deformities in adolescents to recommend proper management [16]. Accurate evaluation of flatfoot in adults requires careful clinical and radiographic evaluation coupled with a thorough understanding of foot anatomy and biomechanics [11]. The Rotterdam Foot Classification system contains 4 categories of anatomic features of the foot [10].

Hallux valgus is a common deformity with multiple surgical options tailored to specific characteristics such as joint congruency and intermetatarsal angle [41]. Late complications such as residual deformity and metatarsalgia are primary causes of unsatisfactory outcomes in bunion surgery [4]. Most patients with successful clinical results after resection of talocalcaneal coalition have a residual functional deficit with continuing difficulties in hindfoot and ankle function [13].

Recurrent bilateral mid-tarsal subluxations suggest an underlying structural abnormality [7]. In children, surgical treatment for symptomatic flat foot deformities significantly improved static segmental alignment and mediolateral foot loading [19]. The same surgical treatment worsened fore-aft loading [19]. One in every ten school-aged children in Southern Ethiopia had a flat foot [18].

Investigations

Plain radiography: Radiographs are essential for evaluating the degree of clubfoot deformity to select proper management [12]. However, they should not be routinely obtained for evaluating nonoperatively corrected clubfoot at age 2 years [30]. In hallux valgus surgery, late complications such as residual deformity and metatarsalgia are primary causes of unsatisfactory outcomes following distal first metatarsal displacement osteotomy [4]. Regardless of deformity severity, all patients with hallux valgus undergoing corrective surgery present with a similar degree of pain and disability [73]. Arthroscopic correction of hallux valgus achieves good clinical and radiologic results, provided careful preoperative clinico–radiologic assessment excludes contraindicated patients [29].

MRI: MRI demonstrates unique patterns of specific muscle-compartment aplasia or hypoplasia in patients with treatment-resistant clubfoot, distinguishing them from those with treatment-responsive clubfoot [53]. Distinct imaging features of multiple plexiform schwannomas in the plantar aspect of the foot may facilitate diagnosis [75].

CT: High-resolution cone-beam CT allows obtainment of measurements analogous to traditional radiographic parameters of adult acquired flatfoot deformity [69].

Other Considerations: Careful clinical and radiographic evaluation, coupled with a thorough understanding of foot anatomy and biomechanics, allows accurate evaluation and appropriate treatment of adult flatfoot [11]. Assessing multi-joint interactions in progressive collapsing foot deformity assists in understanding pathophysiology and surgical treatment planning [2] [33]. The effectiveness of different procedures on radiographic and pedobarographic parameters varies with the severity of an acquired flatfoot deformity [33]. Bilateral mid-tarsal subluxations affecting both feet similarly indicate an underlying structural abnormality [7]. Rigid flatfoot deformities in adolescents have a less predictable clinical course and are associated with various underlying causes; it is critical to investigate the etiology of these deformities to recommend proper management [16]. The most important consideration in clubfoot management is the restoration of normal anatomy while avoiding overcorrection [12]. Early detection and prompt treatment of relapsed deformity following Ponseti method treatment are warranted [34]. Deformity recurrence is common in arthrogryposis and amyoplasia, particularly in skeletally immature patients [77]. In Nepalese patients seen between ages one and five and followed for at least 10 years, a plantigrade foot was achieved in 95% of untreated clubfeet, yet residual deformities remained common despite this initial achievement [1]. For foot macrodactyly, ray amputation provides a measurable reduction in foot size with excellent functional results in children [63]. Ray resection yields the best cosmetic and functional outcomes in feet with macrodactyly involving the lesser toes, whereas involvement of the great toe often yields only fair results requiring repeated soft-tissue debulking after ray resection [68]. PCFD patients showed significant improvement in imaging and clinical evaluations after subtalar arthroereisis with HyProCure, with no significant flatfoot recurrence in patients who had HyProCure removed [62].

Treatment

Non-Operative Management

Nonsurgical treatment is the initial choice for almost all congenital foot deformities [5]. Surgical treatment for congenital foot deformities is generally reserved for patients in whom nonsurgical measures fail to relieve symptoms or improve function [5]. Non-operative treatment cannot correct hallux valgus deformity but can help control symptoms [39]. Non-surgical intervention for hallux rigidus begins with shoe modifications and orthotics [51]. While nonsurgical options exist for ankle arthritis, no evidence indicates that non-surgical treatments change the course of the condition [60]. Non-weightbearing conservative management should be considered the standard of care for tarsal navicular stress fractures [56].

Operative Management: General Principles and Complex Deformities

Indications: Early diagnosis is necessary to initiate treatment for flexible adult acquired flatfoot deformity while the deformity is mild and flexible [3]. Surgical indications for spastic equinovarus foot deformity are primarily focused on obtaining a balanced, braceable, functional lower extremity with a plantigrade foot [14]. Surgical management is indicated for progressive, painful, unilateral coxa vara deformity or leg-length discrepancy [28]. Moderate nonprogressive coxa vara deformity often does not require surgery [28].

Surgical Approach / Technique: The Ilizarov procedure together with osteotomy and soft tissue balance is a safe and effective way to simultaneously correct complex foot deformities and lower limb deformities [40].

Operative Management: Clubfoot

Surgical Approach / Technique: The Ponseti Method achieved a plantigrade foot in 95% of untreated clubfeet in Nepalese patients seen between ages one and five, with outcomes maintained in most patients despite common residual deformities [1]. The Ponseti method is a safe and satisfactory treatment for congenital idiopathic clubfoot with mid-term effectiveness [37]. The Ponseti method demonstrates significant efficacy in neurogenic clubfoot management, achieving initial correction in approximately 90% of cases [45]. Non-operative cast treatment for clubfeet avoids scarring and stiffness but carries risks of rocker-bottom deformity and uncorrected calcaneal rotation [59]. Surgical intervention for clubfeet requires experienced surgeons to avoid complications like stiffness and overcorrection [59].

Operative Management: Hallux Valgus

Indications: Surgical treatment for hallux valgus must be adapted to the type and severity of the deformity, with success rates ranging from 80% to 95% [23].

Surgical Approach / Technique: Arthroscopic correction of hallux valgus can achieve good clinical and radiologic results, provided that careful preoperative clinico–radiologic assessment excludes contraindicated patients [29]. The sling procedure for correction of splay foot, metatarsus primus varus, and hallux valgus has continued to be satisfactory with maintained correction in patients adhering to after-care [9].

Other Considerations: Late complications such as residual deformity and metatarsalgia are the primary causes of unsatisfactory outcomes in distal first metatarsal displacement osteotomy [4].

Operative Management: Flatfoot and Planovalgus Deformity

Surgical Approach / Technique: Effective correction of severe pes planovalgus deformity through complex reconstruction accounts for satisfactory outcomes by relieving pain and restoring function [6]. Distraction arthrodesis of the calcaneocuboid joint in conjunction with stabilization of, and transfer of the flexor digitorum longus tendon to, the midfoot is used to treat acquired pes planovalgus in adults [6]. Double calcaneal osteotomy can be used to correct flatfoot deformities effectively and sustainably, providing symptomatic relief and patient satisfaction [42].

Other Considerations: Calcaneal lengthening osteotomy in ambulatory patients with cerebral palsy and planovalgus foot deformity shows a noticeable tendency toward overcorrection, evidenced by increased pressure exerted on the lateral midfoot [24].

Operative Management: Other Foot Deformities

Surgical Approach / Technique: Talectomy is an effective procedure for the treatment of persistent foot deformities in paediatric patients despite associated complications [8]. Tarsal V-osteotomy permits correction of pes cavus deformity at the most prominent point without the disadvantages of classic techniques [15]. The plantar approach for excision of Morton’s neuroma is recommended if the patient needs a better appearance, as it had less influence on quality of life regarding foot appearance compared to the dorsal approach [31]. Outcomes for procedures addressing metatarsophalangeal joint instability of the lesser toes and plantar plate deficiency are promising, with improvements in pain and function reported along with sustained deformity correction [47].

Other Considerations: Naviculocuneiform arthroscopy is contraindicated in cases of symptomatic flexible flatfoot in adolescents, plantar side coalitions, extensive navicular necrosis, and synovial chondromatosis without joint destruction [57].

Complications

Residual Deformity: Residual deformities are common following the Ponseti Method for untreated clubfeets in patients seen between ages one and five, even when an initial plantigrade foot is achieved in 95% of cases [1]. Relapse affects the subsequent management and outcome of idiopathic clubfoot deformity [26]. A greater delay in walking age may be expected for patients with idiopathic clubfoot who have a very severe deformity or who experience a deformity relapse [32].

Metatarsalgia: Late complications such as residual deformity and metatarsalgia are the primary causes of unsatisfactory outcomes in distal first metatarsal displacement osteotomy for bunion surgery [4].

Functional Deficit: Most patients who undergo resection of talocalcaneal coalition have a residual functional deficit with continuing difficulties in hindfoot and ankle function, despite successful clinical results [13].

Patient Dissatisfaction: Long-term results after surgery for hallux valgus are worse than expected compared to short- and mid-term outcomes, with 25.9% of patients dissatisfied at a mean follow-up of 5.2 years [27].

Poor Long-Term Outcomes: Triple arthrodesis has poor long-term results in patients with cavus foot deformity who have progressive deformity and sensory impairment [54]. Talectomy is associated with complications despite being an effective procedure for persistent foot deformities [8].

Recovery

Light activity (weeks): Specific week ranges for light activity are not provided in the current evidence base.

Full activity (months): Specific month ranges for full activity are not provided in the current evidence base.

Complete recovery / outcome plateau (months): Long-term results for hallux valgus surgery demonstrate that outcomes worsen over time, with 25.9% of patients dissatisfied at a mean follow-up of 5.2 years [27]. For idiopathic clubfoot treated with the Ponseti Method, a greater delay in walking age is expected for infants with very severe deformity or those who experience a deformity relapse [32].

Rehabilitation protocol: The sling procedure provides maintained correction of splay-foot deformity in patients who adhere to after-care [9]. Radiographs should not be routinely obtained for nonoperatively corrected clubfeet at age 2 years [30]. Early detection and prompt treatment of relapsed deformity are warranted following Ponseti method treatment [34].

Functional milestones: The Ponseti Method achieves a plantigrade foot in 95% of untreated clubfeet initially, with maintenance in most patients despite common residual deformities [1]. At follow-up for rigid residual deformity in congenital clubfoot treated with the Ponseti method after walking age, no patient showed an abnormal gait and all feet were plantigrade and flexible, though 2.9% had relapsed [78]. Residual deformity and metatarsalgia are the primary causes of unsatisfactory outcomes in distal first metatarsal displacement osteotomy [4]. Effective correction of severe pes planovalgus deformity through complex reconstruction (distraction arthrodesis of the calcaneocuboid joint with flexor digitorum longus tendon transfer) results in satisfactory outcomes via pain relief and restoration of function [6]. Talectomy is an effective procedure for treating persistent foot deformities despite associated complications [8]. Most patients experience a residual functional deficit with continuing difficulties in hindfoot and ankle function following resection of talocalcaneal coalition, despite successful clinical results [13]. Tarsal V-osteotomy permits correction of pes cavus deformity at the most prominent point without the disadvantages of classic techniques [15]. Excellent mid-term results can be expected after foot polydactyly resection in childhood [25]. The development of relapse affects the subsequent management and outcome of idiopathic clubfoot deformity [26]. Many patients with clubfoot treated with extensive soft-tissue release have poor long-term foot function [50]. Treatment for forefoot disorders ranges from nonsurgical modifications to specific surgical procedures such as osteotomies, tendon transfers, and joint reconstructions depending on the stage and nature of the deformity [79].

Other Considerations: The Ponseti Method achieves a plantigrade foot in 95% of untreated clubfeet initially, with maintenance in most patients despite common residual deformities [1]. At follow-up for rigid residual deformity in congenital clubfoot treated with the Ponseti method after walking age, no patient showed an abnormal gait and all feet were plantigrade and flexible, though 2.9% had relapsed [78].

Key Evidence

  • [L4] A plantigrade foot was achieved in 95% of the feet initially and was maintained in most of the patients, although residual deformities were common. (10.2106/jbjs.18.00445)
  • [L4] Assessing multi-joint interactions in progressive collapsing foot deformity will lead to a better understanding of the pathophysiology and assist in surgical treatment planning. (10.1186/s13018-026-06670-1)
  • [L5] The article discusses the pathophysiology, classification, and treatment options for flexible adult acquired flatfoot deformity, emphasizing the controversy regarding the best surgical technique and the need for early diagnosis to initiate treatment while the deformity is mild and flexible. (10.1007/s00167-009-1015-6)
  • [L4] The relief of pain and the restoration of function achieved through effective correction of the severe pes planovalgus deformity account for the satisfactory outcomes. (10.2106/00004623-199911000-00006)
  • [Case_report] The fact that both feet were similarly affected indicates that there was some underlying structural abnormality. (10.2106/00004623-197961040-00027)
  • [L4] Talectomy is an effective procedure for the treatment of persistent foot deformities despite associated complications. (10.1186/s12891-021-04309-2)
  • [L4] The procedure has continued to be satisfactory with maintained correction of splay-foot deformity in patients adhering to after-care. (10.2106/00004623-196446030-00026)
  • [L4] The proposed classification system contains 4 categories of anatomic features of the foot. (10.2106/jbjs.15.01416)
  • [L5] Careful clinical and radiographic evaluation, coupled with a thorough understanding of the anatomy and biomechanics of the foot, will allow accurate evaluation and appropriate treatment. (10.5435/00124635-199509000-00005)
  • [L5] Club feet vary in severity, and the degree of deformity must be evaluated clinically and radiographically to select the proper management; the most important consideration is the restoration of normal anatomy while avoiding overcorrection. (10.2106/00004623-198567070-00001)
  • [L3] Although most patients had a successful clinical result, most had a residual functional deficit with continuing difficulties in hindfoot and ankle function. (10.2106/00004623-199703000-00008)
  • [L5] Surgical indications are primarily focused on obtaining a balanced, braceable, functional lower extremity with a plantigrade foot. (10.5435/jaaos-d-23-01007)
  • [L4] The procedure permits correction of deformity at the most prominent point without the disadvantages of classic techniques. (10.2106/00004623-196850050-00005)
  • [L5] Rigid flatfoot deformities in adolescents have a less predictable clinical course and are associated with various underlying causes, making it critical to investigate the etiology to recommend proper management. (10.5435/jaaos-d-21-00448)
  • [L4] Macrodactyly of the foot is a rare congenital malformation with diverse clinical manifestations and multiple elements' involvement. (10.1186/s13018-020-02196-2)
  • [L4] One in every ten children had a flat foot. (10.1186/s12891-023-07082-6)
  • [L4] Surgical treatment resulted in significantly improved static segmental alignment and mediolateral foot loading, but worsened fore-aft loading. (10.1302/0301-620x.95b5.30594)
  • [L4] Club foot is not a single entity requiring a uniform treatment; surgical methods must be selected based on a clear understanding of the specific anatomical and functional derangement in each foot. (10.2106/00004623-196749080-00021)
  • [L5] Surgical treatment for hallux valgus must be adapted to the type and severity of the deformity, with success rates ranging from 80% to 95%. (10.1302/2058-5241.1.000015)
  • [L3] Furthermore, our findings highlight a noticeable tendency toward the overcorrection of the deformity, as evidenced by increased pressure exerted on the lateral midfoot. (10.2106/jbjs.24.00394)
  • [L3] Excellent mid-term results can be expected after foot polydactyly resection in childhood. (10.1302/0301-620x.103b2.bjj-2020-1341.r2)
  • [L3] The development of a relapse affects the subsequent management and outcome of clubfoot deformity. (10.5435/jaaos-d-16-00522)
  • [L3] When using a validated outcome score for the assessment of outcome after surgery for hallux valgus, the long-term results are worse than expected when compared with the short- and mid-term outcomes, with 25.9% of patients dissatisfied at a mean follow-up of 5.2 years. (10.1302/0301-620x.97b2.34891)
  • [L5] Surgical management is indicated for progressive, painful, unilateral deformity or leg-length discrepancy, while moderate nonprogressive deformity often does not require surgery. (10.5435/00124635-199803000-00003)
  • [L4] Arthroscopic correction of the hallux valgus deformity can achieve good clinical and radiologic results, provided that careful preoperative clinico–radiologic assessment is made to exclude patients contraindicated for the procedure. (10.1016/j.arthro.2008.03.001)
  • [L3] Such radiographs should not be routinely obtained for this purpose. (10.2106/jbjs.16.00693)
  • [L3] The plantar approach is recommended if the patient needs a better appearance, as it had less influence on quality of life regarding foot appearance compared to the dorsal approach. (10.1186/s12891-022-05858-w)
  • [L4] A greater delay may be expected for those patients who have a very severe deformity or those who experience a deformity relapse. (10.2106/jbjs.m.01525)
  • [L5] In a cadaver model, the effectiveness of different procedures on radiographic and pedobarographic parameters varies with the severity of an acquired flatfoot deformity. (10.2106/jbjs.e.00045)
  • [L5] Early detection and prompt treatment of relapsed deformity are warranted. (10.5435/jaaos-d-15-00624)
  • [L4] Ponseti method is a safe and satisfactory treatment for congenital idiopathic clubfoot with mid-term effectiveness. (10.1186/1749-799x-6-3)
  • [L5] Non-operative treatment cannot correct the deformity but can help control symptoms. (10.1302/2058-5241.1.000005)
  • [L4] The therapeutic strategy by using the Ilizarov procedure together with osteotomy and soft tissue balance is a safe and effective way to simultaneously correct complex foot deformities and lower limb deformities. (10.1186/s13018-020-02021-w)
  • [L4] Double calcaneal osteotomy could be used to correct flatfoot deformities effectively and sustainably and provide symptomatic relief and patient satisfaction. (10.1186/s13018-024-05106-y)
  • [L1] The Ponseti method demonstrates significant efficacy in neurogenic clubfoot management, achieving initial correction in approximately 90% of cases. (10.1186/s13018-025-06492-7)
  • [L5] Outcomes of these procedures are promising, with improvements in pain and function reported along with sustained deformity correction. (10.5435/jaaos-22-04-235)
  • [L5] The new PCFD classification system offers an option to aid surgeons in approaching this complex 3-dimensional deformity and individualizing treatment for each patient's unique anatomy, although it has room for improvement. (10.5435/jaaos-d-24-01499)
  • [L3] Many patients with clubfoot treated with an extensive soft-tissue release have poor long-term foot function. (10.2106/00004623-200611000-00034)
  • [Paper] Non-surgical intervention begins with shoe modifications and orthotics. (10.1302/2058-5241.2.160031)
  • [L5] Hallux valgus is a complex deformity influenced by both extrinsic factors, such as constricting footwear, and intrinsic factors, including heredity and foot mechanics. (10.2106/00004623-199606000-00018)
  • [L4] MRI demonstrated a range of soft-tissue abnormalities in patients, including unique patterns of specific muscle-compartment aplasia/hypoplasia that were present in patients with treatment-resistant clubfoot and not present in patients with treatment-responsive clubfoot. (10.2106/jbjs.m.01257)
  • [L5] Surgical options include soft-tissue and plantar fascia releases for a flexible deformity, osteotomy for a fixed deformity, and tendon transfers to restore muscle balance, while triple arthrodesis has poor long-term results in patients with progressive deformity and sensory impairment. (10.5435/00124635-200305000-00007)
  • [L4] It can be recommended for the comprehensive assessment of the clinical conditions of patients with hallux valgus (HV) deformity in Mainland China. (10.1186/s13018-025-06196-y)
  • [L1] Non-weightbearing conservative management should be considered the standard of care for tarsal navicular stress fractures. (10.1177/0363546509355408)
  • [Paper] The procedure is indicated for specific pathologies but is contraindicated in cases of symptomatic flexible flatfoot in adolescents, plantar side coalitions, extensive navicular necrosis, and synovial chondromatosis without joint destruction. (10.1016/j.eats.2017.11.003)
  • [L5] The debate centers on whether to prioritize non-operative cast treatment or timely surgical intervention; while non-operative treatment avoids scarring and stiffness, it carries risks of rocker-bottom deformity and uncorrected calcaneal rotation, whereas surgery requires experienced surgeons to avoid complications like stiffness and overcorrection. (10.2106/00004623-198668010-00024)
  • [L4] PCFD patients showed significant improvement in imaging and clinical evaluations after SA, with no significant flatfoot recurrence in patients who had HyProCure removed. (10.1186/s13018-024-05406-3)
  • [L4] Ray amputation gave a measurable reduction in foot size with excellent functional results. (10.1302/0301-620x.97b10.35660)
  • [L4] During weight-loading process, the first metatarsal-cuneiform joint turns dorsiflexed, supinated, and internally rotated. (10.1186/s13018-015-0289-2)
  • [L5] A wedge under the lateral aspect of the forefoot decreases strain in the plantar aponeurosis, whereas a wedge under the medial aspect increases strain. (10.2106/00004623-199910000-00005)
  • [L4] Ray resection results in the best cosmetic and functional outcomes in feet with involvement of the lesser toes, while involvement of the great toe often yields only fair results requiring repeated soft-tissue debulking. (10.2106/00004623-200207000-00015)
  • [L2] Measurements analogous to traditional radiographic parameters of adult acquired flatfoot deformity are obtainable using high-resolution cone-beam CT. (10.2106/jbjs.16.01366)
  • [L4] Hallux valgus deformity and its severity were positively associated with the magnitude of the anteroposterior postural sway. (10.1186/s12891-021-04385-4)
  • [L4] Regardless of the severity of the deformity, all patients had a similar degree of pain and disability. (10.2106/jbjs.b.00288)
  • [Case_report] The distinct imaging features presented may facilitate the diagnosis process in the future. (10.1186/1471-2474-15-342)
  • [L5] Deformity recurrence is common, particularly in skeletally immature patients. (10.5435/00124635-200211000-00006)
  • [L4] At the time of follow-up, no patient showed an abnormal gait, all feet were plantigrade and flexible, but 2 feet (2.9%) had relapsed. (10.2106/jbjs.16.00053)

See Also

References

[1] Outcomes of the Ponseti Method for Untreated Clubfeet in Nepalese Patients Seen Between the Ages of One and Five Years and Followed for at Least 10 Years. Journal of Bone and Joint Surgery. 2018. DOI: 10.2106/jbjs.18.00445

[2] A multiple joint morphometric analysis of female patients with progressive collapsing foot deformity: a cross-sectional study. Journal of Orthopaedic Surgery and Research. 2026. DOI: 10.1186/s13018-026-06670-1

[3] Operative management options for symptomatic flexible adult acquired flatfoot deformity: a review. Knee Surgery, Sports Traumatology, Arthroscopy. 2010. DOI: 10.1007/s00167-009-1015-6

[4] Distal First Metatarsal Displacement Osteotomy: ITS PLACE IN THE SCHEMA OF BUNION SURGERY.. The Journal of Bone and Joint Surgery. American Volume. 1974.

[5] Chapter 28 Congenital Disorders of the Foot. 2020.

[6] Complex Reconstruction for the Treatment of Dorsolateral Peritalar Subluxation of the Foot. Early Results After Distraction Arthrodesis of the Calcaneocuboid Joint in Conjunction with Stabilization of, and Transfer of the Flexor Digitorum Longus Tendon to, the Midfoot to Treat Acquired Pes Planovalgus in Adults. The Journal of Bone & Joint Surgery*. 1999. DOI: 10.2106/00004623-199911000-00006

[7] Recurrent bilateral mid-tarsal subluxations. A case report.. The Journal of Bone & Joint Surgery. 1979. DOI: 10.2106/00004623-197961040-00027

[8] Complications associated with talectomy in paediatric patients: a comparative retrospective study of two surgical techniques. BMC Musculoskeletal Disorders. 2021. DOI: 10.1186/s12891-021-04309-2

[9] SLING PROCEDURE FOR CORRECTION OF SPLAY FOOT, METATARSUS PRIMUS VARUS, AND HALLUX VALGUS. The Journal of Bone & Joint Surgery. 1964. DOI: 10.2106/00004623-196446030-00026

[10] The Rotterdam Foot Classification. Journal of Bone and Joint Surgery. 2016. DOI: 10.2106/jbjs.15.01416

[11] Flatfoot in the Adult. Journal of the American Academy of Orthopaedic Surgeons. 1995. DOI: 10.5435/00124635-199509000-00005

[12] The management of club foot.. The Journal of Bone & Joint Surgery. 1985. DOI: 10.2106/00004623-198567070-00001

[13] Gait Abnormalities following Resection of Talocalcaneal Coalition. The Journal of Bone & Joint Surgery*. 1997. DOI: 10.2106/00004623-199703000-00008

[14] Spastic Equinovarus Foot Deformity. Journal of the American Academy of Orthopaedic Surgeons. 2024. DOI: 10.5435/jaaos-d-23-01007

[15] Surgical Treatment of Pes Cavus by Tarsal V-Osteotomy. The Journal of Bone & Joint Surgery. 1968. DOI: 10.2106/00004623-196850050-00005

[16] Evaluation and Management of Adolescents With a Stiff Flatfoot. Journal of the American Academy of Orthopaedic Surgeons. 2022. DOI: 10.5435/jaaos-d-21-00448

[17] Clinical characteristics of 93 cases of isolated macrodactyly of the foot in children. Journal of Orthopaedic Surgery and Research. 2021. DOI: 10.1186/s13018-020-02196-2

[18] Magnitude of flat foot and its associated factors among school-aged children in Southern Ethiopia: an institution-based cross-sectional study. BMC Musculoskeletal Disorders. 2023. DOI: 10.1186/s12891-023-07082-6

[19] The operative correction of symptomatic flat foot deformities in children. The Bone & Joint Journal. 2013. DOI: 10.1302/0301-620x.95b5.30594

[20] The Role of Surgery in the Treatment of Club Feet. The Journal of Bone & Joint Surgery. 1967. DOI: 10.2106/00004623-196749080-00021

[23] Hallux valgus, ankle osteoarthrosis and adult acquired flatfoot deformity: a review of three common foot and ankle pathologies and their treatments. EFORT Open Reviews. 2016. DOI: 10.1302/2058-5241.1.000015

[24] Outcomes of Calcaneal Lengthening Osteotomy in Ambulatory Patients with Cerebral Palsy and Planovalgus Foot Deformity. Journal of Bone and Joint Surgery. 2025. DOI: 10.2106/jbjs.24.00394

[25] Mid-term foot function and pedobarographic analysis of 52 feet after polydactyly resection in childhood. The Bone & Joint Journal. 2021. DOI: 10.1302/0301-620x.103b2.bjj-2020-1341.r2

[26] The Timing and Relevance of Relapsed Deformity in Patients With Idiopathic Clubfoot. Journal of the American Academy of Orthopaedic Surgeons. 2017. DOI: 10.5435/jaaos-d-16-00522

[27] Surgery for the correction of hallux valgus. The Bone & Joint Journal. 2015. DOI: 10.1302/0301-620x.97b2.34891

[28] Coxa Vara in Childhood: Evaluation and Management. Journal of the American Academy of Orthopaedic Surgeons. 1998. DOI: 10.5435/00124635-199803000-00003

[29] Arthroscopy‐Assisted Correction of Hallux Valgus Deformity. Arthroscopy. 2008. DOI: 10.1016/j.arthro.2008.03.001

[30] Nonoperatively Corrected Clubfoot at Age 2 Years. Journal of Bone and Joint Surgery. 2017. DOI: 10.2106/jbjs.16.00693

[31] Plantar and dorsal approaches for excision of morton’s neuroma: a comparison study. BMC Musculoskeletal Disorders. 2022. DOI: 10.1186/s12891-022-05858-w

[32] Walking Age of Infants with Idiopathic Clubfoot Treated Using the Ponseti Method. Journal of Bone and Joint Surgery. 2014. DOI: 10.2106/jbjs.m.01525

[33] Correction of Moderate and Severe Acquired Flexible Flatfoot with Medializing Calcaneal Osteotomy and Flexor Digitorum Longus Transfer. The Journal of Bone & Joint Surgery. 2006. DOI: 10.2106/jbjs.e.00045

[34] Management of the Relapsed Clubfoot Following Treatment Using the Ponseti Method. Journal of the American Academy of Orthopaedic Surgeons. 2017. DOI: 10.5435/jaaos-d-15-00624

[37] Mid-term Results of Ponseti Method for the treatment of Congenital Idiopathic Clubfoot - (A Study of 67 Clubfeet with Mean Five Year Follow-Up). Journal of Orthopaedic Surgery and Research. 2011. DOI: 10.1186/1749-799x-6-3

[39] Treatment of hallux valgus deformity. EFORT Open Reviews. 2016. DOI: 10.1302/2058-5241.1.000005

[40] Complex foot deformities associated with lower limb deformities: a new therapeutic strategy for simultaneous correction using Ilizarov procedure together with osteotomy and soft tissue release. Journal of Orthopaedic Surgery and Research. 2020. DOI: 10.1186/s13018-020-02021-w

[41] Chapter 110 Disorders of the First Ray. 2019.

[42] Clinical and radiological outcomes of flexible flatfoot correction with double calcaneal osteotomy. Journal of Orthopaedic Surgery and Research. 2024. DOI: 10.1186/s13018-024-05106-y

[45] Effectiveness of the ponseti method in treating neurogenic clubfoot: a systematic review and meta-analysis. Journal of Orthopaedic Surgery and Research. 2025. DOI: 10.1186/s13018-025-06492-7

[46] Chapter 135 Pediatric Lower Extremity Deformities and Limb Deficiencies. 2019.

[47] Metatarsophalangeal Joint Instability of the Lesser Toes and Plantar Plate Deficiency. Journal of the American Academy of Orthopaedic Surgeons. 2014. DOI: 10.5435/jaaos-22-04-235

[48] Chapter 46 Foot Fractures and Dislocations. 2021.

[49] So What Exactly Is Progressive Collapsing Foot Deformity?. Journal of the American Academy of Orthopaedic Surgeons. 2025. DOI: 10.5435/jaaos-d-24-01499

[50] Long-Term Follow-up of Patients with Clubfeet Treated with Extensive Soft-Tissue Release. The Journal of Bone & Joint Surgery. 2006. DOI: 10.2106/00004623-200611000-00034

[51] Hallux rigidus. EFORT Open Reviews. 2017. DOI: 10.1302/2058-5241.2.160031

[52] Instructional Course Lectures, The American Academy of Orthopaedic Surgeons - Hallux Valgus†. The Journal of Bone & Joint Surgery*. 1996. DOI: 10.2106/00004623-199606000-00018

[53] Soft-Tissue Abnormalities Associated with Treatment-Resistant and Treatment-Responsive Clubfoot. Journal of Bone and Joint Surgery. 2014. DOI: 10.2106/jbjs.m.01257

[54] Cavus Foot Deformity in Children. Journal of the American Academy of Orthopaedic Surgeons. 2003. DOI: 10.5435/00124635-200305000-00007

[55] A cross-cultural adaptation and validation of the Chinese version of American orthopaedic foot and ankle society hallux metatarsophalangeal-interphalangeal scale (AOFAS-Hallux-MTP-IP) in patients with hallux valgus. Journal of Orthopaedic Surgery and Research. 2025. DOI: 10.1186/s13018-025-06196-y

[56] Management of Tarsal Navicular Stress Fractures. The American Journal of Sports Medicine. 2010. DOI: 10.1177/0363546509355408

[57] Naviculocuneiform Arthroscopy. Arthroscopy Techniques. 2018. DOI: 10.1016/j.eats.2017.11.003

[59] Surgical correction of club feet.. The Journal of Bone & Joint Surgery. 1986. DOI: 10.2106/00004623-198668010-00024

[60] Chapter 43 Degenerative Conditions and Osteonecrosis of the Foot and Ankle. 2020.

[62] HyProCure for progressive collapsing foot deformity: is subtalar arthroereisis a good procedure?. Journal of Orthopaedic Surgery and Research. 2024. DOI: 10.1186/s13018-024-05406-3

[63] Ray amputation for the treatment of foot macrodactyly in children. The Bone & Joint Journal. 2015. DOI: 10.1302/0301-620x.97b10.35660

[64] Mobility of the first metatarsal-cuneiform joint in patients with and without hallux valgus: in vivo three-dimensional analysis using computerized tomography scan. Journal of Orthopaedic Surgery and Research. 2015. DOI: 10.1186/s13018-015-0289-2

[65] The Influence of Medial and Lateral Placement of Orthotic Wedges on Loading of the Plantar Aponeurosis. An in Vitro Study. The Journal of Bone & Joint Surgery*. 1999. DOI: 10.2106/00004623-199910000-00005

[68] Macrodactyly of the Foot. The Journal of Bone & Joint Surgery. 2002. DOI: 10.2106/00004623-200207000-00015

[69] Flexible Adult Acquired Flatfoot Deformity. Journal of Bone and Joint Surgery. 2017. DOI: 10.2106/jbjs.16.01366

[72] Hallux valgus deformity and postural sway: a cross-sectional study. BMC Musculoskeletal Disorders. 2021. DOI: 10.1186/s12891-021-04385-4

[73] Age-Adjusted Baseline Data for Women with Hallux Valgus Undergoing Corrective Surgery. The Journal of Bone & Joint Surgery. 2005. DOI: 10.2106/jbjs.b.00288

[75] Multiple plexiform schwannomas in the plantar aspect of the foot: case report and literature review. BMC Musculoskeletal Disorders. 2014. DOI: 10.1186/1471-2474-15-342

[77] Arthrogryposis and Amyoplasia. Journal of the American Academy of Orthopaedic Surgeons. 2002. DOI: 10.5435/00124635-200211000-00006

[78] Ponseti Treatment of Rigid Residual Deformity in Congenital Clubfoot After Walking Age. Journal of Bone and Joint Surgery. 2016. DOI: 10.2106/jbjs.16.00053

[79] Chapter 111 Forefoot Disorders. 2019.

Creative Commons BY-NC 4.0

CC Creative Commons licence
BY Attribution — you must credit the source
NC NonCommercial — not for commercial use

Attribution-NonCommercial 4.0 International

Creative Commons Corporation ("Creative Commons") is not a law firm and does not provide legal services or legal advice. Distribution of Creative Commons public licenses does not create a lawyer-client or other relationship. Creative Commons makes its licenses and related information available on an "as-is" basis. Creative Commons gives no warranties regarding its licenses, any material licensed under their terms and conditions, or any related information. Creative Commons disclaims all liability for damages resulting from their use to the fullest extent possible.

Using Creative Commons Public Licenses

Creative Commons public licenses provide a standard set of terms and conditions that creators and other rights holders may use to share original works of authorship and other material subject to copyright and certain other rights specified in the public license below. The following considerations are for informational purposes only, are not exhaustive, and do not form part of our licenses.

Considerations for licensors: Our public licenses are intended for use by those authorized to give the public permission to use material in ways otherwise restricted by copyright and certain other rights. Our licenses are irrevocable. Licensors should read and understand the terms and conditions of the license they choose before applying it. Licensors should also secure all rights necessary before applying our licenses so that the public can reuse the material as expected. Licensors should clearly mark any material not subject to the license. This includes other CC- licensed material, or material used under an exception or limitation to copyright. More considerations for licensors: wiki.creativecommons.org/Considerations_for_licensors

Considerations for the public: By using one of our public licenses, a licensor grants the public permission to use the licensed material under specified terms and conditions. If the licensor's permission is not necessary for any reason--for example, because of any applicable exception or limitation to copyright--then that use is not regulated by the license. Our licenses grant only permissions under copyright and certain other rights that a licensor has authority to grant. Use of the licensed material may still be restricted for other reasons, including because others have copyright or other rights in the material. A licensor may make special requests, such as asking that all changes be marked or described. Although not required by our licenses, you are encouraged to respect those requests where reasonable. More considerations for the public: wiki.creativecommons.org/Considerations_for_licensees

Creative Commons Attribution-NonCommercial 4.0 International Public License

By exercising the Licensed Rights (defined below), You accept and agree to be bound by the terms and conditions of this Creative Commons Attribution-NonCommercial 4.0 International Public License ("Public License"). To the extent this Public License may be interpreted as a contract, You are granted the Licensed Rights in consideration of Your acceptance of these terms and conditions, and the Licensor grants You such rights in consideration of benefits the Licensor receives from making the Licensed Material available under these terms and conditions.

Section 1 -- Definitions.

a. Adapted Material means material subject to Copyright and Similar Rights that is derived from or based upon the Licensed Material and in which the Licensed Material is translated, altered, arranged, transformed, or otherwise modified in a manner requiring permission under the Copyright and Similar Rights held by the Licensor. For purposes of this Public License, where the Licensed Material is a musical work, performance, or sound recording, Adapted Material is always produced where the Licensed Material is synched in timed relation with a moving image.

b. Adapter's License means the license You apply to Your Copyright and Similar Rights in Your contributions to Adapted Material in accordance with the terms and conditions of this Public License.

c. Copyright and Similar Rights means copyright and/or similar rights closely related to copyright including, without limitation, performance, broadcast, sound recording, and Sui Generis Database Rights, without regard to how the rights are labeled or categorized. For purposes of this Public License, the rights specified in Section 2(b)(1)-(2) are not Copyright and Similar Rights.

d. Effective Technological Measures means those measures that, in the absence of proper authority, may not be circumvented under laws fulfilling obligations under Article 11 of the WIPO Copyright Treaty adopted on December 20, 1996, and/or similar international agreements.

e. Exceptions and Limitations means fair use, fair dealing, and/or any other exception or limitation to Copyright and Similar Rights that applies to Your use of the Licensed Material.

f. Licensed Material means the artistic or literary work, database, or other material to which the Licensor applied this Public License.

g. Licensed Rights means the rights granted to You subject to the terms and conditions of this Public License, which are limited to all Copyright and Similar Rights that apply to Your use of the Licensed Material and that the Licensor has authority to license.

h. Licensor means the individual(s) or entity(ies) granting rights under this Public License.

i. NonCommercial means not primarily intended for or directed towards commercial advantage or monetary compensation. For purposes of this Public License, the exchange of the Licensed Material for other material subject to Copyright and Similar Rights by digital file-sharing or similar means is NonCommercial provided there is no payment of monetary compensation in connection with the exchange.

j. Share means to provide material to the public by any means or process that requires permission under the Licensed Rights, such as reproduction, public display, public performance, distribution, dissemination, communication, or importation, and to make material available to the public including in ways that members of the public may access the material from a place and at a time individually chosen by them.

k. Sui Generis Database Rights means rights other than copyright resulting from Directive 96/9/EC of the European Parliament and of the Council of 11 March 1996 on the legal protection of databases, as amended and/or succeeded, as well as other essentially equivalent rights anywhere in the world.

l. You means the individual or entity exercising the Licensed Rights under this Public License. Your has a corresponding meaning.

Section 2 -- Scope.

a. License grant.

1. Subject to the terms and conditions of this Public License, the Licensor hereby grants You a worldwide, royalty-free, non-sublicensable, non-exclusive, irrevocable license to exercise the Licensed Rights in the Licensed Material to:

a. reproduce and Share the Licensed Material, in whole or in part, for NonCommercial purposes only; and

b. produce, reproduce, and Share Adapted Material for NonCommercial purposes only.

2. Exceptions and Limitations. For the avoidance of doubt, where Exceptions and Limitations apply to Your use, this Public License does not apply, and You do not need to comply with its terms and conditions.

3. Term. The term of this Public License is specified in Section 6(a).

4. Media and formats; technical modifications allowed. The Licensor authorizes You to exercise the Licensed Rights in all media and formats whether now known or hereafter created, and to make technical modifications necessary to do so. The Licensor waives and/or agrees not to assert any right or authority to forbid You from making technical modifications necessary to exercise the Licensed Rights, including technical modifications necessary to circumvent Effective Technological Measures. For purposes of this Public License, simply making modifications authorized by this Section 2(a) (4) never produces Adapted Material.

5. Downstream recipients.

a. Offer from the Licensor -- Licensed Material. Every recipient of the Licensed Material automatically receives an offer from the Licensor to exercise the Licensed Rights under the terms and conditions of this Public License.

b. No downstream restrictions. You may not offer or impose any additional or different terms or conditions on, or apply any Effective Technological Measures to, the Licensed Material if doing so restricts exercise of the Licensed Rights by any recipient of the Licensed Material.

6. No endorsement. Nothing in this Public License constitutes or may be construed as permission to assert or imply that You are, or that Your use of the Licensed Material is, connected with, or sponsored, endorsed, or granted official status by, the Licensor or others designated to receive attribution as provided in Section 3(a)(1)(A)(i).

b. Other rights.

1. Moral rights, such as the right of integrity, are not licensed under this Public License, nor are publicity, privacy, and/or other similar personality rights; however, to the extent possible, the Licensor waives and/or agrees not to assert any such rights held by the Licensor to the limited extent necessary to allow You to exercise the Licensed Rights, but not otherwise.

2. Patent and trademark rights are not licensed under this Public License.

3. To the extent possible, the Licensor waives any right to collect royalties from You for the exercise of the Licensed Rights, whether directly or through a collecting society under any voluntary or waivable statutory or compulsory licensing scheme. In all other cases the Licensor expressly reserves any right to collect such royalties, including when the Licensed Material is used other than for NonCommercial purposes.

Section 3 -- License Conditions.

Your exercise of the Licensed Rights is expressly made subject to the following conditions.

a. Attribution.

1. If You Share the Licensed Material (including in modified form), You must:

a. retain the following if it is supplied by the Licensor with the Licensed Material:

i. identification of the creator(s) of the Licensed Material and any others designated to receive attribution, in any reasonable manner requested by the Licensor (including by pseudonym if designated);

ii. a copyright notice;

iii. a notice that refers to this Public License;

iv. a notice that refers to the disclaimer of warranties;

v. a URI or hyperlink to the Licensed Material to the extent reasonably practicable;

b. indicate if You modified the Licensed Material and retain an indication of any previous modifications; and

c. indicate the Licensed Material is licensed under this Public License, and include the text of, or the URI or hyperlink to, this Public License.

2. You may satisfy the conditions in Section 3(a)(1) in any reasonable manner based on the medium, means, and context in which You Share the Licensed Material. For example, it may be reasonable to satisfy the conditions by providing a URI or hyperlink to a resource that includes the required information.

3. If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.

4. If You Share Adapted Material You produce, the Adapter's License You apply must not prevent recipients of the Adapted Material from complying with this Public License.

Section 4 -- Sui Generis Database Rights.

Where the Licensed Rights include Sui Generis Database Rights that apply to Your use of the Licensed Material:

a. for the avoidance of doubt, Section 2(a)(1) grants You the right to extract, reuse, reproduce, and Share all or a substantial portion of the contents of the database for NonCommercial purposes only;

b. if You include all or a substantial portion of the database contents in a database in which You have Sui Generis Database Rights, then the database in which You have Sui Generis Database Rights (but not its individual contents) is Adapted Material; and

c. You must comply with the conditions in Section 3(a) if You Share all or a substantial portion of the contents of the database.

For the avoidance of doubt, this Section 4 supplements and does not replace Your obligations under this Public License where the Licensed Rights include other Copyright and Similar Rights.

Section 5 -- Disclaimer of Warranties and Limitation of Liability.

a. UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHER. THIS INCLUDES, WITHOUT LIMITATION, WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU.

b. TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR IN PART, THIS LIMITATION MAY NOT APPLY TO YOU.

c. The disclaimer of warranties and limitation of liability provided above shall be interpreted in a manner that, to the extent possible, most closely approximates an absolute disclaimer and waiver of all liability.

Section 6 -- Term and Termination.

a. This Public License applies for the term of the Copyright and Similar Rights licensed here. However, if You fail to comply with this Public License, then Your rights under this Public License terminate automatically.

b. Where Your right to use the Licensed Material has terminated under Section 6(a), it reinstates:

1. automatically as of the date the violation is cured, provided it is cured within 30 days of Your discovery of the violation; or

2. upon express reinstatement by the Licensor.

For the avoidance of doubt, this Section 6(b) does not affect any right the Licensor may have to seek remedies for Your violations of this Public License.

c. For the avoidance of doubt, the Licensor may also offer the Licensed Material under separate terms or conditions or stop distributing the Licensed Material at any time; however, doing so will not terminate this Public License.

d. Sections 1, 5, 6, 7, and 8 survive termination of this Public License.

Section 7 -- Other Terms and Conditions.

a. The Licensor shall not be bound by any additional or different terms or conditions communicated by You unless expressly agreed.

b. Any arrangements, understandings, or agreements regarding the Licensed Material not stated herein are separate from and independent of the terms and conditions of this Public License.

Section 8 -- Interpretation.

a. For the avoidance of doubt, this Public License does not, and shall not be interpreted to, reduce, limit, restrict, or impose conditions on any use of the Licensed Material that could lawfully be made without permission under this Public License.

b. To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions.

c. No term or condition of this Public License will be waived and no failure to comply consented to unless expressly agreed to by the Licensor.

d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.

Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the CC0 Public Domain Dedication. Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at creativecommons.org/policies, Creative Commons does not authorize the use of the trademark "Creative Commons" or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.

Creative Commons may be contacted at creativecommons.org.