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拇外翻矫正

Updated Sep 2026
Illustration: foot

本页面由机器翻译,尚未经临床医生审核。英文版本为权威版本。

为何建议进行此手术

拇外翻是大脚趾根部出现的隆起,此时脚趾向其他脚趾方向偏移。鞋头狭窄和高跟鞋可能会促成此问题,且该问题在某些家族中存在遗传倾向。女性比男性更常见,且通常会随时间推移而恶化。最常见的症状是隆起处的疼痛,穿鞋时会加剧。有些人还会感到足底前部(跖骨头)疼痛,或在小脚趾上出现问题。

我们通常首先尝试非手术治疗:穿更宽的鞋子、使用脚趾分隔器和夜间矫形器。这些措施可以缓解症状,但无法使脚趾变直。当这些措施未能提供足够的改善时,我们会考虑手术。该手术通过切割并重新排列大脚趾的骨骼来矫正畸形。其主要目的是缓解疼痛,使穿鞋和行走更加舒适。

手术前

一旦预约了手术,我们将根据您站立时拍摄的足部X光片来规划手术。这些影像显示脚趾偏斜的程度,并帮助我们为您的足部选择合适的手术方式。部分患者还需要进行核磁共振(MRI)或超声检查;如果适用,我们会告知您。

在手术前的几天里,请继续服用您通常服用的药物,除非我们另有指示。您需要在术前七小时停止进食和饮水。我们要求七小时而非六小时,以便如果手术室手术列表提前完成,可以提前安排您的手术。请安排他人在术后驾车送您回家,因为您将无法自行驾驶。手术当天请穿着宽松舒适的衣物,并携带您目前服用药物的清单。如果您有其他健康状况,术前可能需要进行血液检查或由麻醉师进行评估。

手术当日

您将抵达医院的手术入院单元,在此办理入院手续并做术前准备。您将在该处与麻醉医生见面。本手术在全身麻醉下进行。有时会追加区域神经阻滞以缓解术后疼痛;麻醉医生将在手术当日就此与您沟通。

随后,您将被带入手术室进行手术。术后,您将在复苏区苏醒,护士会在此监测您的状况,直至麻醉作用消退。待您的生命体征稳定后,根据手术类型及您的恢复情况,您将被转入病房或直接回家。

手术内容

矫正拇外翻有多种方法,适合您的具体手术取决于您的脚趾偏斜程度。共同点是,外科医生会切开并重新对齐您大脚趾的骨骼,然后在骨骼愈合期间将其固定在新的位置。

对于轻度或中度拇外翻,切口通常位于大脚趾附近,骨骼会被横向移动至更直的线上。有时,在脚趾本身进行第二个小切口有助于平衡。对于更严重的拇外翻,骨骼可能在足部更靠后的位置被切开。如果脚趾基部的关节不稳定或磨损,可能会进行关节融合术,使骨骼愈合为一体。

某些手术是通过一个或两个小切口使用特殊器械进行的,而不是较长的开放切口。您的外科医生会告诉您哪种方法适合您的足部。

手术结束时,切口用缝合线关闭,并覆盖敷料和绷带。您将带着关于足部护理的说明回家,我们将再次为您检查愈合情况。

术后

您将在恢复区苏醒,麻醉消退期间,护士会全程看护。您的足部将用敷料和绷带包扎,我们会给您用药以缓解不适。大多数人术后不久即可站立并行走几步,通常需穿特殊鞋具以保护足部。回家后,前24小时内应有人陪同。您的医疗团队会告知您是当天出院还是住院一晚。敷料需保留约10天;除非我们指示,否则请勿提前拆除。我们会在复诊时为您更换或拆除敷料。

恢复

在最初几天和几周内,您的脚部会出现酸痛和肿胀。这是愈合过程中的正常现象。休息、抬高脚部以及我们开具的止痛药将有助于缓解不适。肿胀通常会反复出现,完全消退可能需要一段时间。

您在屋内走动时,需穿着特制鞋以保护脚部。您的物理治疗师将指导您进行简单的练习,以保持脚趾和踝关节的活动度并增强肌肉力量。您可以完成家中大多数轻体力任务,但初期应尽可能避免脚部负重,并遵循我们给出的指示。仰卧或侧卧睡觉,并用枕头将脚部抬高,可能会感觉更舒适。

恢复的里程碑以事件而非具体日期为标志。在我们复诊并更换敷料后,将检查您脚部的愈合情况。当肿胀消退后,穿鞋会再次变得舒适。随着活动度和力量恢复,行走会变得更加轻松,您的物理治疗师会告知您何时可以开始进行更多活动。一旦您不再服用强效止痛药,且能在紧急制动时迅速做出反应,即可驾驶;我们的独立驾驶指南中有更多详细信息。

每个人的恢复情况各不相同。您的时间表可能有所不同,您的外科医生和物理治疗师将在整个过程中为您提供指导。

可能出现的并发症

大多数患者恢复良好,但偶尔也会出现问题。您的外科医生和医疗团队会密切监测您的状况,以便尽早发现任何问题。

有时脚趾可能被矫正得过度,导致其向另一只脚的方向倾斜。您可能会注意到您的大脚趾向内偏移,或者足内侧出现新的疼痛。如果脚趾看起来朝向错误方向,请在下次复诊时告知我们。仔细护理敷料并按时随访有助于保持脚趾在矫正后的位置。

为足背和大脚趾内侧提供感觉的神经走行于我们手术区域附近。在关节镜手术中,其中一条神经位于我们需小心避开的区域。如果神经受到刺激,您可能会感到脚趾麻木、刺痛或局部感觉异常。如果这种感觉未消退,请在复诊时告知我们。

我们截断的骨骼需要紧密贴合才能愈合。在某些足部形态中,骨块可能无法充分对合。如果骨骼移位或未能连接,您可能会注意到咔哒声或研磨感、手术部位疼痛加剧,或脚趾回弹。如果出现上述任何情况,请告知我们,我们可能需要通过X光检查愈合情况。

您的足部形态也很重要。如果您有大拇趾外翻且跖骨较窄,截骨后骨端可能无法良好接触。如果您外翻角度较小且跖骨较长,实现完全矫正可能较为困难。我们会根据您的X光片制定手术方案,以适应您的足部形态,并会就此与您讨论其具体含义。

本页的并发症表格列出了典型发生率,如果您想了解具体数据,可查阅该表。

何时联系我们

大多数问题都会较早出现,我们更希望尽早得知。如果您出现发热、伤口红肿或渗液加重,或疼痛持续加剧而非缓解,请致电我们。如果您的小腿出现肿胀或压痛,也请致电我们。如果您突然感到呼吸困难或出现胸痛,或者出现突发剧烈疼痛、足部或脚趾感觉丧失,或无法活动足部或脚趾,请立即前往急诊。如果您的大脚趾开始向另一只脚的方向内偏,请告知我们。


Evidence & references

This is the clinical evidence summary written for health professionals. It is technical, and it lists the research this page was built from. You do not need to read it to understand your treatment or to make a decision about it.

Anatomy & Pathophysiology

Definition and Etiology

  • Hallux valgus is defined as lateral deviation of the great toe with medial deviation of the first metatarsal [3].
  • Hallux valgus is defined as lateral deviation of the proximal phalanx on the first metatarsal head [9].
  • Hallux valgus deformity is defined as the lateral deviation of the proximal phalanx of the first metatarsophalangeal joint [10].
  • The etiology of hallux valgus is likely multifactorial, involving intrinsic factors such as genetic predisposition, ligamentous laxity, and predisposing anatomy [3].
  • Extrinsic factors such as certain types of shoewear, including narrow toe boxes and high heels, play a role in the pathophysiology of hallux valgus [3].
  • Hallux valgus is more common in women than in men [9].
  • The incidence of hallux valgus deformity is 10 times greater in women than in men [14].
  • Of patients with hallux valgus, 70% have a family history of the condition, suggesting a hereditary component [9].
  • Hallux valgus is frequently associated with medial deviation of the first metatarsal [9].
  • Metatarsus primus varus and pes planus have been implicated in the etiology of hallux valgus [9].
  • Other causes of hallux valgus include rheumatoid arthritis, connective tissue disorders, and cerebral palsy [9].
  • Hallux valgus is not associated with chronic tightness of the Achilles tendon or gastrocnemius, increased first ray mobility, bilaterality, or pes planus [14].
  • The deformity is usually progressive, although the rate and degree of progression is often nonlinear [10].
  • Hallux valgus is most commonly seen in female patients in their fourth or fifth decades of life [10].

Pathoanatomy

  • The pathoanatomy of hallux valgus involves gradual failure of the medial supportive structures, specifically the medial collateral ligament and tibial sesamoid, resulting in a varus position of the first metatarsal [10].
  • Medial capsular attenuation is a component of the pathoanatomy of hallux valgus [3].
  • The proximal phalanx drifts laterally in hallux valgus [3].
  • Plantar-lateral migration of the abductor hallucis causes the proximal phalangeal unit to plantar flex and pronate the hallux [3].
  • The pronation of the hallux is amplified by the proximal phalangeal attachment of the adductor hallucis [3].
  • Stretching of the extensor hood of the extensor hallucis longus occurs in hallux valgus [3].
  • Lateral deviation of the extensor hallucis longus and flexor hallucis longus causes a muscular imbalance and deforming force for valgus progression and pronation of the great toe [3].
  • The first metatarsal head moves medially off the sesamoids, increasing the intermetatarsal angle [3].
  • Pronation leads to rounding of the lateral metatarsal head, which should have a flat contour with no rotational deformity [3].
  • Secondary contracture of the lateral capsule, adductor hallucis, and lateral metatarsal-sesamoid and intermetatarsal ligaments occurs in hallux valgus [3].
  • With chronic deformity, the medial joint capsule becomes attenuated, and the lateral joint capsule becomes contracted [14].
  • The sesamoids slowly erode the crista as the metatarsal head is pushed medially, allowing for lateral subluxation of the sesamoids from directly plantar to the first metatarsal [14].
  • With severe deformity, both extrinsic and intrinsic muscles lie lateral to the longitudinal axis of the first metatarsophalangeal joint, enhancing the deformity [14].
  • Pronation of the hallux occurs because attenuation of the dorsomedial capsule allows the abductor hallucis tendon to slide beneath the metatarsal head and rotate the proximal phalanx into a position of pronation [14].
  • The sesamoid ridge on the plantar surface of the first metatarsal head (the crista) flattens because of pressure from the tibial sesamoid [16].
  • The fibular sesamoid displaces partially or completely into the first intermetatarsal space when the crista flattens [16].
  • The deep transverse intermetatarsal ligament runs between the plantar plates at the metatarsophalangeal joints and does not insert into bone on the adjacent sides of the metatarsal heads [16].
  • The valgus posture of the great toe frequently causes a hammer toe-like deformity of the second toe [16].
  • Secondary pathology and deformity can develop in the lesser toes, such as hammertoes and claw toes, which may be symptomatic [10].

Radiographic Angles and Normal Values

  • The hallux valgus angle (HVA) is the angle formed by the line along the first metatarsal shaft and the line along the shaft of the proximal phalanx [3].
  • The normal hallux valgus angle is less than 15 degrees [3].
  • The first-second intermetatarsal angle (IMA) is the angle formed by lines along the first and second metatarsal shafts [3].
  • The normal first-second intermetatarsal angle is less than 9 degrees [3].
  • The hallux valgus interphalangeus (HVI) angle is the angle formed by lines along the shafts of the proximal phalanx and distal phalanx [3].
  • The normal hallux valgus interphalangeus angle is less than 10 degrees [3].
  • The distal metatarsal articular angle (DMAA) is the angle formed by the line along the articular surface of the first metatarsal and the line perpendicular to the axis of the first metatarsal [3].
  • The normal distal metatarsal articular angle is less than 10 degrees [3].
  • An increased distal metatarsal articular angle is associated with a congruent deformity [3].
  • The normal hallux valgus angle is ≤15° [9].
  • The normal intermetatarsal angle is ≤9° [9].
  • The normal distal metatarsal articular angle is ≤15° [9].
  • The normal proximal phalangeal articular angle (PPAA) is ≤10° [9].
  • The normal hallux valgus angle is <15 degrees [27].
  • The normal intermetatarsal angle is <9 degrees [27].
  • The normal distal metatarsal articular angle is <10 degrees [27].
  • The normal hallux valgus interphalangeus angle is <10 degrees [27].

Juvenile and Adolescent Pathophysiology

  • Hallux valgus in adolescents is frequently hereditary and usually seen in early adolescence [7].
  • Adolescent hallux valgus is almost always found in conjunction with a wide forefoot caused by varus of the first metatarsal shaft (metatarsus primus varus) [7].
  • The wide forefoot allows severe lateral deviation of the great toe, causing the prominent base of the great toe to rub against the inside of the shoe [7].
  • Juvenile hallux valgus is often associated with a smaller medial eminence prominence, increased magnitude of the first-second intermetatarsal angle, increased hypermobility of the first tarsometatarsal joint, and less pronation than in adults [20].
  • Juveniles are more likely to have bilateral deformities and a family history of hallux valgus [20].
  • A congruent joint with an increased distal metatarsal articular angle is more common in juvenile hallux valgus than in the adult condition [25].
  • Generalized ligamentous laxity may be more common in children with hallux valgus than in the general population [25].
  • Recurrence of the deformity after surgical correction is a critical factor separating juvenile and adolescent patients from adult patients [11].
  • Varus of the first metatarsal with a large intermetatarsal angle is commonly present in juvenile hallux valgus [11].
  • The distal metatarsal articular angle is typically increased in juvenile hallux valgus [11].

Hallux Varus Pathophysiology

  • Hallux varus is described as a medial deviation of the great toe at the MTP joint [2].
  • Acquired hallux varus is rare in children but usually acquired in adults as a complication of hallux valgus surgery [2].
  • The most common cause of hallux varus is iatrogenic deformity resulting from hallux valgus repair, with an incidence of 2% to 10% [21].
  • Causes of acquired hallux varus include overcorrection from bunion surgeries such as the McBride procedure, trauma, and systemic arthritis [2].
  • The main causes for hallux varus after hallux valgus surgery include complete release of lateral structures combined with excessive plication of the medial capsule, excessive resection of the medial eminence, excision of the fibular sesamoid, release of the lateral head of the flexor hallucis brevis, and closure of the intermetatarsal angle to neutral or a negative value [13].
  • Hallux varus can be classified into static (supple) and dynamic (fixed) types [13].
  • Static hallux varus is asymptomatic and mainly a cosmetic complication, with all deformity occurring at the metatarsophalangeal joint in the transverse or frontal plane [13].
  • Dynamic hallux varus is a multiplanar deformity that is often fixed, symptomatic, and difficult to correct surgically [13].
  • In dynamic hallux varus, the first metatarsophalangeal joint is hyperextended and the interphalangeal joint is acutely flexed [13].
  • Hallux varus is defined as a hallux valgus angle measuring 0° or less [21].
  • Hallux varus may be associated with an extension deformity of the MTP joint and flexion of the interphalangeal joint [21].
  • Supination of the hallux may be seen in hallux varus [21].
  • Hallux varus may be associated with inflammatory conditions such as rheumatoid arthritis or neurologic conditions such as Charcot-Marie-Tooth disease [21].

Congenital Hallux Varus

  • Congenital hallux varus can occur in isolation with a normal first metatarsal, where a taut fibrous band runs from the medial side of the great toe to the base of the first metatarsal [2].
  • Congenital hallux varus may coexist with other malformations of the foot, such as a longitudinal bracket epiphysis of the first metatarsal or preaxial polydactyly [2].
  • Congenital hallux varus is uncommonly part of an underlying skeletal dysplasia, such as diastrophic dwarfism [2].
  • Congenital hallux varus is typically unilateral and associated with a short, thick first metatarsal, accessory bones or toes, varus deformity of lateral metatarsals, or a firm fibrous band extending from the medial side of the great toe to the base of the first metatarsal [24].
  • The explanation for congenital hallux varus is that two great toes originate in utero, but the medial or accessory one fails to develop, and the rudimentary medial toe and fibrous band act like a taut bowstring pulling the great toe into varus [24].

Neuromuscular Pathophysiology

  • Hallux valgus deformity in patients with cerebral palsy is usually associated with other deformities such as equinovalgus foot, heel valgus, and external rotation of the tibia [17].
  • These conditions cause the foot to pronate, forcing the first metatarsophalangeal joint into abduction and creating a hallux valgus deformity [17].
  • The extensor hallucis tendon may sublux into the first web space and become an abductor of the hallux, leading to further deformity in cerebral palsy [17].
  • Hallux valgus in patients with cerebral palsy develops in response to an equinovalgus deformity of the hindfoot [22].
  • Spasticity of the peroneus longus leads to progressive eversion and abduction of the foot, resulting in lateralization of the origin of the adductor hallucis muscle and increasing pull of the proximal phalanx into adduction [22].
  • When combined with external tibial torsion, the toe is pushed laterally as weight is borne by the everted forefoot [22].

Clinical Presentation

Definition and Etiology

  • Hallux valgus is defined as lateral deviation of the great toe with medial deviation of the first metatarsal [3].
  • Hallux valgus is defined as lateral deviation of the proximal phalanx on the first metatarsal head [9].
  • Hallux valgus deformity is defined as the lateral deviation of the proximal phalanx of the first metatarsophalangeal joint [10].
  • The etiology of hallux valgus is likely multifactorial, involving intrinsic factors such as genetic predisposition, ligamentous laxity, and predisposing anatomy [3].
  • Extrinsic factors contributing to hallux valgus include certain types of shoewear, specifically narrow toe boxes and high heels [3].
  • Hallux valgus is more common in women than in men [9].
  • The incidence of hallux valgus deformity is 10 times greater in women than in men [14].
  • The incidence of hallux valgus is significantly higher in shod populations than unshod ones [14].
  • Of patients with hallux valgus, 70% have a family history of the condition, suggesting a hereditary component [9].
  • Other causes of hallux valgus include rheumatoid arthritis, connective tissue disorders, and cerebral palsy [9].
  • Hallux valgus is not associated with chronic tightness of the Achilles tendon or gastrocnemius, increased first ray mobility, bilaterality, or pes planus [14].
  • Hallux valgus in patients with cerebral palsy develops in response to an equinovalgus deformity of the hindfoot [22].
  • In patients with cerebral palsy, spasticity of the peroneus longus leads to progressive eversion and abduction of the foot, resulting in lateralization of the origin of the adductor hallucis muscle [22].

Pathoanatomy

  • The pathoanatomy of hallux valgus involves medial capsular attenuation [3].
  • The proximal phalanx drifts laterally, leading to plantar-lateral migration of the abductor hallucis [3].
  • Plantar-lateral migration of the abductor hallucis causes the proximal phalangeal unit to plantar flex and pronate the hallux [3].
  • The pronation of the hallux is amplified by the proximal phalangeal attachment of the adductor hallucis [3].
  • Lateral deviation of the extensor hallucis longus and flexor hallucis longus causes a muscular imbalance and deforming force for valgus progression and pronation of the great toe [3].
  • The first metatarsal head moves medially off the sesamoids, increasing the intermetatarsal angle [3].
  • Pronation leads to rounding of the lateral metatarsal head, which should have a flat contour with no rotational deformity [3].
  • Secondary contracture occurs in the lateral capsule, adductor hallucis, and lateral metatarsal-sesamoid and intermetatarsal ligaments [3].
  • The pathoanatomy involves gradual failure of the medial supportive structures, including the medial collateral ligament and tibial sesamoid, resulting in a varus position of the first metatarsal [10].
  • As the deformity progresses, the alignment of the flexor and extensor hallucis longus tendons shifts laterally relative to the metatarsophalangeal joint, further exacerbating the deformity [10].
  • The first metatarsal varus results in a prominent first metatarsal head medially, which is the bump or "bunion" reported by the patient [10].
  • This prominent medial eminence is a common source of pain related to shoe wear [10].
  • Secondary pathology and deformity can develop in the lesser toes, such as hammertoes and claw toes, which may be symptomatic [10].
  • With chronic deformity, the medial joint capsule becomes attenuated, and the lateral joint capsule becomes contracted [14].
  • The sesamoids slowly erode the crista as the metatarsal head is pushed medially, allowing for lateral subluxation of the sesamoids from directly plantar to the first metatarsal [14].
  • Pronation of the hallux occurs because attenuation of the weakest portion of the capsule (the dorsomedial aspect) allows the abductor hallucis tendon to slide beneath the metatarsal head and rotate the proximal phalanx into a position of pronation [14].

Symptoms and Signs

  • The most common symptom of hallux valgus is pain over the medial eminence [14].
  • Patients also complain of pain in the joint and pain under the second metatarsal head, known as a transfer lesion or metatarsalgia [14].
  • The deformity may prevent shoewear, and activity limitation may be part of the constellation of symptoms [14].
  • While seated, the first metatarsophalangeal joint area is evaluated for signs of local irritation and bursal hypertrophy secondary to shoe wear [10].
  • Tenderness over the medial eminence is evaluated during the physical examination [10].
  • Range of motion of the first metatarsophalangeal joint is evaluated, and any pain with motion may suggest arthritis within the joint [10].
  • Numbness can occur in the dorsal medial cutaneous nerve distribution because of external pressure from a shoe [10].
  • The first tarsometatarsal joint is evaluated for hypermobility, which remains a diagnostic challenge with poor reproducibility [10].
  • The severity of the hallux valgus deformity and any associated pes planus can be best assessed while the patient is standing [10].
  • Pronation of the great toe is easily noted by comparing the angulation of the nail of the great toe in relation to the floor [3].

Radiographic Evaluation

  • Diagnostic confirmation of hallux valgus is made with the use of standard AP and lateral weight-bearing radiographs, as non-weight-bearing radiographs tend to underestimate the deformity [10].
  • Radiographs should be assessed for presence of arthritis at the first metatarsophalangeal joint, severity of the deformity, sesamoid subluxation, and the hallux valgus angle [10].
  • Radiographs are assessed for first tarsometatarsal hypermobility and congruency of the metatarsophalangeal joint [10].
  • The hallux valgus angle is the angle formed by the line along the first metatarsal shaft and the line along the shaft of the proximal phalanx [3].
  • The normal hallux valgus angle is less than 15 degrees [3].
  • The first-second intermetatarsal angle is the angle formed by lines along the first and second metatarsal shafts [3].
  • The normal first-second intermetatarsal angle is less than 9 degrees [3].
  • The hallux valgus interphalangeus angle is the angle formed by lines along the shafts of the proximal phalanx and distal phalanx [3].
  • The normal hallux valgus interphalangeus angle is less than 10 degrees [3].
  • The distal metatarsal articular angle is the angle formed by the line along the articular surface of the first metatarsal and the line perpendicular to the axis of the first metatarsal [3].
  • The normal distal metatarsal articular angle is less than 10 degrees [3].
  • An increased distal metatarsal articular angle is associated with a congruent deformity [3].
  • A congruent joint has no lateral subluxation of the proximal phalanx in relation to the first metatarsal head [14].
  • An incongruent joint has lateral subluxation of the proximal phalanx on the metatarsal head [14].
  • Arthrosis of the metatarsophalangeal joint is characterized by joint space narrowing, subchondral sclerosis, and osteophyte formation [14].
  • The first tarsometatarsal joint angle is based on the distal articular surface of the medial cuneiform and the longitudinal axis of the first metatarsal [14].
  • Excessive medial deviation of the first tarsometatarsal joint may indicate that hypermobility is present [14].

Juvenile and Adolescent Presentation

  • Hallux valgus is rare in children but often requires treatment in adolescents [7].
  • Adolescent hallux valgus is frequently hereditary and usually seen in early adolescence [7].
  • Adolescent hallux valgus is almost always found in conjunction with a wide forefoot caused by varus of the first metatarsal shaft, known as metatarsus primus varus [7].
  • The wide forefoot allows severe lateral deviation of the great toe, causing the prominent base of the great toe to rub against the inside of the shoe and create a painful bunion [7].
  • Recurrence of the deformity after surgical correction is a critical factor separating juvenile and adolescent patients from adult patients [11].
  • Varus of the first metatarsal with a large intermetatarsal angle is commonly present in juvenile and adolescent patients [11].
  • The distal metatarsal articular angle is typically increased in juvenile and adolescent patients [11].
  • Hallux valgus interphalangeus may be present in juvenile and adolescent patients [11].
  • Ligamentous laxity may be present, and a history of Ehlers-Danlos or Marfan syndrome should be elicited [11].
  • Family history is frequently positive for hallux valgus in juvenile and adolescent patients [11].

Hallux Varus Presentation

  • Hallux varus is described as a medial deviation of the great toe at the metatarsophalangeal joint [2].
  • In adults, hallux varus is usually acquired as a complication of hallux valgus surgery [2].
  • Symptoms from hallux varus are both cosmetic and related to the ability to wear shoes [2].
  • Shoe wear is nearly impossible with the deviation of the great toe seen in hallux varus [2].
  • The deformity of hallux varus is believed to worsen with age [2].
  • Hallux varus can be classified into two types: static (supple) and dynamic (fixed) [13].
  • Static hallux varus is asymptomatic and mainly a cosmetic complication [13].
  • In static hallux varus, the hallux rests in varus in a weight-bearing position, while the metatarsophalangeal joint rests in a normal position in the sagittal plane [13].
  • Dynamic hallux varus deformity is a multiplanar deformity that is often fixed, symptomatic, and difficult to correct surgically [13].
  • In dynamic hallux varus, the first metatarsophalangeal joint is hyperextended, usually with some degree of fixed soft-tissue contracture [13].
  • In dynamic hallux varus, the interphalangeal joint is acutely flexed [13].
  • The most common complaint in dynamic hallux varus is that the toe box of the shoe rubs on the dorsomedial surface of the interphalangeal joint [13].
  • A keratotic lesion may be present beneath the first metatarsal head in dynamic hallux varus, caused by the extended hallux pushing the first metatarsal head plantarward [13].
  • Lesser toes may develop a hammer deformity and metatarsalgia in dynamic hallux varus as the hallux assists less in the stance phase of the gait cycle [13].

Hallux Rigidus Presentation

  • Hallux rigidus is defined as a condition in which there is restriction of motion at the first metatarsophalangeal joint [26].
  • Initial symptoms of hallux rigidus mainly consist of pain during gait [26].
  • Discomfort in the metatarsophalangeal joint is greatest during heel rise because the great toe normally dorsiflexes at this time [26].
  • Physical examination reveals painful limitation in dorsiflexion of the first metatarsophalangeal joint [26].
  • Dorsiflexion is lost before plantar flexion is in hallux rigidus [26].
  • There is often a palpable osteophyte on the dorsum of the joint, and swelling may be present [26].
  • The base of the metatarsal appears more plantar than normal, and the metatarsal head is elevated [26].
  • Observation of gait shows that patients walk on the lateral border of the feet to avoid rolling over the great toe [26].
  • Radiographs show narrowing of the joint in hallux rigidus [26].
  • Lateral plain films can demonstrate dorsal osteophytes at the base of the proximal phalanx and metatarsal head [26].
  • The exostoses may become quite large and obscure visualization of the joint itself [26].

Investigations

Radiographic Angles and Measurements

  • The hallux valgus angle (HVA) is defined as the angle formed by the intersection of lines along the shaft of the first metatarsal and the shaft of the proximal phalanx [3].
  • The first-second intermetatarsal angle (IMA) is defined as the angle formed by lines along the shafts of the first and second metatarsals [3].
  • The hallux valgus interphalangeus (HVI) angle is defined as the angle formed by lines along the shafts of the proximal phalanx and the distal phalanx [3].
  • The distal metatarsal articular angle (DMAA) is defined as the angle formed by the line along the articular surface of the first metatarsal and a line perpendicular to the axis of the first metatarsal [3].
  • The proximal phalangeal articular angle (PPAA) is defined as the articular angle of the base of the proximal phalanx in relation to its longitudinal axis [9].
  • The normal proximal phalangeal articular angle is less than or equal to 10 degrees [9].
  • The distal metatarsal articular angle is measured as the angle of the line bisecting the metatarsal shaft with a line through the base of the distal articular cartilage cap [9].
  • The normal distal metatarsal articular angle is less than or equal to 15 degrees [9].
  • The normal hallux valgus angle is less than or equal to 15 degrees [9].
  • The normal first-second intermetatarsal angle is less than or equal to 9 degrees [9].
  • The normal distal metatarsal articular angle is less than 10 degrees of lateral deviation [14].
  • The distal metatarsal articular angle is the angle created by the line connecting the ends of the articular surface and a line perpendicular to the long axis of the first metatarsal [10].

Imaging Modalities and Assessment

  • Diagnostic confirmation of hallux valgus is made with standard anteroposterior and lateral weight-bearing radiographs [10].
  • Non-weight-bearing radiographs tend to underestimate the severity of the hallux valgus deformity [10].
  • Weight-bearing radiographs are important to evaluate the type and severity of the hallux valgus deformity [14].
  • Radiographic evaluation includes assessing the congruency of the first metatarsophalangeal joint, where a congruent joint has no lateral subluxation of the proximal phalanx and an incongruent joint has lateral subluxation [14].
  • Radiographs are assessed for the presence of arthritis at the first metatarsophalangeal joint, characterized by joint space narrowing, subchondral sclerosis, and osteophyte formation [14].
  • Radiographs are assessed for first tarsometatarsal hypermobility, which may be indicated by medial subluxation and incongruency on anteroposterior views or dorsal subluxation with plantar gapping on lateral views [10].
  • The position of the medial sesamoid in relation to a line drawn down the midaxis of the first metatarsal is evaluated, with postoperative sesamoid positions 5 to 7 associated with higher recurrence of deformity [9].
  • Weight-bearing computed tomography scans have been used to assess foot alignment in patients with hallux rigidus [1].

Clinical Examination

  • The severity of the hallux valgus deformity and any associated pes planus is best assessed while the patient is standing [10].
  • The first metatarsocuneiform joint is examined for hypermobility by stabilizing the medial cuneiform and ranging the first metatarsal dorsomedially and plantolaterally [14].
  • Range of motion of the first metatarsophalangeal joint is checked in both the deformed and corrected positions to determine the degree of surgical correction possible without impairing motion [14].
  • The skin is evaluated for erythema, swelling, ulceration, or callosities during the clinical examination [14].
  • Neurovascular status of the foot is assessed, noting absent pulses and venous stasis changes [14].
  • Doppler studies are obtained if there is any question regarding the circulatory status of the foot [14].
  • The first tarsometatarsal joint is evaluated for hypermobility, which remains a diagnostic challenge with poor reproducibility [10].
  • Numbness can occur in the dorsal medial cutaneous nerve distribution due to external pressure from a shoe [10].
  • Pain with motion of the first metatarsophalangeal joint may suggest arthritis within the joint [10].

Specific Deformity Assessments

  • Hallux varus is defined as a hallux valgus angle measuring 0 degrees or less [21].
  • Hallux varus can be associated with an extension deformity of the metatarsophalangeal joint and flexion of the interphalangeal joint [21].
  • Supination of the hallux may be seen in association with hallux varus [21].
  • It must be determined whether metatarsophalangeal and interphalangeal joint deformities in hallux varus are fixed or passively correctable [21].
  • Weight-bearing radiographs can help determine the degree of arthrosis in hallux varus [21].
  • Congenital hallux varus may occur in isolation with a normal first metatarsal, coexist with other foot malformations such as longitudinal bracket epiphysis or preaxial polydactyly, or be part of an underlying skeletal dysplasia [2].
  • Adolescent hallux valgus is frequently found in conjunction with a wide forefoot caused by varus deviation of the first metatarsal shaft (metatarsus primus varus) [7].
  • The distal metatarsal articular angle is an offset of the articular surface that is a predisposing factor in the development of hallux valgus [9].
  • The proximal phalangeal articular angle is an offset of the articular angle that is a predisposing factor in the development of hallux valgus [9].
  • The first-second intermetatarsal angle is not influenced by overresection of the medial eminence and is not accurate for postoperative evaluation of distal osteotomies [9].

Treatment

Non-Operative Management

  • Nonsurgical management should be considered first in all juvenile and adolescent patients with hallux valgus, especially those with ligamentous laxity or neuromuscular disorders [20].
  • Shoes with a wide toe box, toe spacers, and night splints may be used for symptomatic management of juvenile hallux valgus until physeal closure [20].
  • Nonoperative treatment of acquired hallux varus is limited to accommodation of the deformity with shoe modifications and shoe stretching [11].

Operative Correction: Juvenile and Adolescent Hallux Valgus

  • In juvenile and adolescent patients, proximal osteotomy is performed through the medial cuneiform if the first metatarsal physis is open [11].
  • If arthrodesis of the first tarsometatarsal (TMT) joint is required for ligamentous laxity in juvenile patients, surgical intervention is delayed until physeal closure [11].
  • For juvenile hallux valgus with hallux valgus interphalangeus (HVI), an Akin osteotomy is indicated [11].
  • For juvenile hallux valgus with increased distal metatarsal articular angle (DMAA) and an intermetatarsal angle (IMA) of 13 degrees or less, a biplanar distal chevron osteotomy is indicated [11].
  • For juvenile hallux valgus with HVI, increased DMAA, and an IMA of 13 degrees or less, an Akin osteotomy combined with a biplanar distal chevron osteotomy is indicated [11].
  • For juvenile hallux valgus with an IMA greater than 13 degrees and increased DMAA, a biplanar distal chevron osteotomy combined with an open-wedge medial cuneiform osteotomy is indicated [11].
  • For juvenile hallux valgus with HVI, increased DMAA, and an IMA greater than 13 degrees, an Akin osteotomy combined with a biplanar distal chevron osteotomy and an open-wedge medial cuneiform osteotomy is indicated [11].
  • In cases of ligamentous laxity in juvenile patients, a first TMT arthrodesis substitutes for a proximal osteotomy to correct the IMA [11].
  • Arthrodesis of the metatarsophalangeal joint is appropriate for juvenile hallux valgus in patients with ligamentous laxity (Ehlers-Danlos syndrome), cerebral palsy, Down syndrome, and rheumatoid arthritis [20].
  • Surgery for adolescent hallux valgus must address the deformity by trimming the bunion, correcting the varus angulation of the first metatarsal by osteotomy, and centralizing and balancing the hallux valgus by lengthening the adductor hallucis muscle [7].

Operative Correction: Adult Hallux Valgus

  • Indications for soft-tissue repair for recurrent hallux valgus include a first-second intermetatarsal angle of ≤13 degrees [5].
  • Indications for soft-tissue repair for recurrent hallux valgus include a hallux valgus angle of ≤30 degrees [5].
  • Indications for soft-tissue repair for recurrent hallux valgus include a normal distal metatarsal articular angle (<10-15 degrees) [5].
  • Indications for soft-tissue repair for recurrent hallux valgus include minimal degenerative changes at the first metatarsophalangeal joint [5].
  • Indications for soft-tissue repair for recurrent hallux valgus include 50 to 60 degrees of passive motion of the first metatarsophalangeal joint [5].
  • Indications for soft-tissue repair for recurrent hallux valgus include subluxation but not complete dislocation of sesamoid bones [5].
  • Indications for soft-tissue repair for recurrent hallux valgus include the ability to displace the first metatarsal laterally at the metatarsocuneiform joint from its abnormal varus inclination [5].
  • Indications for soft-tissue repair for recurrent hallux valgus include some degree of longitudinal arch present when weight bearing [5].
  • If the longitudinal arch is improved with passive dorsiflexion of the hallux while standing, the deformity is not fixed and a soft-tissue repair is likely to endure [5].
  • Soft-tissue repair for recurrent hallux valgus involves releasing the adductor hallucis tendon from the capsule, capsulosesamoid ligament, and lateral border of the fibular sesamoid [5].
  • Soft-tissue repair for recurrent hallux valgus involves removing the adductor hallucis tendon from its insertion into the base of the proximal phalanx [5].
  • Soft-tissue repair for recurrent hallux valgus involves sectioning the deep transverse intermetatarsal ligament to allow medial mobility of the fibular sesamoid [5].
  • If the fibular sesamoid cannot be placed into its facet on the inferior surface of the first metatarsal head, the lateral capsule is sectioned from dorsal to the fibular sesamoid [5].

Operative Correction: Hallux Varus

  • Surgery for congenital hallux varus consists of release of the tight tissues on the medial side of the toe, including the abductor hallucis and the medial capsule of the MTP joint [2].
  • In surgery for congenital hallux varus, the great toe is usually syndactylized to the second toe to maintain correction [2].
  • Temporary fixation of the MTP joint with a Kirschner wire is performed during surgery for congenital hallux varus to maintain position while tissues heal [2].
  • Arthrodesis of the first MTP joint is reserved for cases of congenital hallux varus in whom primary reconstruction fails and painful arthritis develops [2].
  • Flexible acquired hallux varus deformity can be corrected with a soft tissue procedure involving release of the abductor hallucis (ABH) muscle and fascia [11].
  • Flexible acquired hallux varus deformity can be corrected by transferring a portion of the extensor hallucis longus (EHL) or extensor hallucis brevis (EHB) tendon under the transverse intermetatarsal ligament to the distal metatarsal neck [11].
  • In EHL or EHB tendon transfer for hallux varus, the distal portion of the tendon is left intact to create a dynamic stabilizer [11].
  • Suture button augmentation is commonly used with tendon reconstruction for hallux varus but should not be utilized in isolation [11].
  • Fixed acquired hallux varus deformity, or deformity with limited first MTP motion, joint pain, or presence of first MTP degenerative joint disease, is treated with a first MTP arthrodesis [11].

Operative Correction: Special Populations

  • In patients with cerebral palsy, underlying deformities such as heel valgus or external rotation of the tibia should be corrected before surgical correction of the hallux valgus [17].
  • Isolated soft-tissue procedures for hallux valgus in patients with cerebral palsy rarely are successful and have a high recurrence rate [17].
  • Great toe metatarsophalangeal joint fusion is recommended for hallux valgus in patients with cerebral palsy [17].
  • First metatarsophalangeal joint fusion has been shown to provide the best overall outcome with functional gains and anatomic correction of the deformity being maintained in patients with cerebral palsy [17].

Complications

  • Acquired hallux varus is usually acquired as a complication of hallux valgus surgery in adults [2].
  • Overcorrection from bunion surgeries, such as the McBride procedure, is a cause of acquired hallux varus [2].
  • Trauma is a cause of acquired hallux varus [2].
  • Systemic arthritis is a cause of acquired hallux varus [2].
  • Arthrodesis of the first metatarsophalangeal joint is reserved for cases where primary reconstruction fails and painful arthritis develops [2].

Recovery

  • Return to sport and physical activities is a documented outcome following first metatarsophalangeal joint arthrodesis in young patients [1].
  • Improved ankle push-off power is observed following cheilectomy for hallux rigidus [1].

References

[1] Campbell S Operative Orthopaedics 4 Volume Set. MULTIPLE Z-PLASTY RELEASE OF A CONGENITAL RING > HALLUX RIGIDUS.

[2] Tachdjian S Pediatric Orthopaedics From The Texas Scottish Rite Hospital For Children E Book. Plate 15.3 Kramer/Barmada Osteotomy of the Base of the Femoral Neck for Slipped Capital Femoral Epiphysis > Distal Metatarsal Osteotomy > Hallux Varus.

[3] Miller S Review Of Orthopaedics. SECTION 16 PATELLAR TRACKING IN TOTAL KNEE ARTHROPLASTY > ADULT HALLUX VALGUS.

[5] Campbell S Operative Orthopaedics 4 Volume Set. MULTIPLE Z-PLASTY RELEASE OF A CONGENITAL RING > RECURRENT HALLUX VALGUS WITH NORMAL DISTAL METATARSAL ANGLE AFTER BUNIONECTOMY > BOX 82.6.

[7] A Lange Medical Book Current Diagnosis Treatment In Orthopedics Fifth Edition. 10Pediatric Orthopedic Surgery > 9. Adolescent Bunions (Hallux Valgus).

[9] Aaos Comprehensive Orthopaedic Review 3. Disorders of the First Ray > I. Hallux Valgus.

[10] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Foot and Ankle Reconstruction > Hallux Valgus.

[11] Miller S Review Of Orthopaedics. JUVENILE AND ADOLESCENT HALLUX VALGUS.

[13] Campbell S Operative Orthopaedics 4 Volume Set. MULTIPLE Z-PLASTY RELEASE OF A CONGENITAL RING > ACQUIRED HALLUX VARUS AND INTRINSIC MINUS HALLUX.

[14] A Lange Medical Book Current Diagnosis Treatment In Orthopedics Fifth Edition. 8Foot and Ankle Surgery > 1. Hallux Valgus.

[16] Campbell S Operative Orthopaedics 4 Volume Set. MULTIPLE Z-PLASTY RELEASE OF A CONGENITAL RING > HALLUX VALGUS (BUNION).

[17] Campbell S Operative Orthopaedics 4 Volume Set. COMBINED ONE-STAGE CORRECTION OF SPASTIC DISLOCATED HIP > HALLUX VALGUS DEFORMITY.

[20] Orthopaedic Knowledge Update. Congenital Disorders of the Foot* > Juvenile Hallux Valgus.

[21] Aaos Comprehensive Orthopaedic Review 3. Disorders of the First Ray > III. Hallux Varus.

[22] Tachdjian S Pediatric Orthopaedics From The Texas Scottish Rite Hospital For Children E Book. Pigmented Villonodular Synovitis and Giant Cell Tumor of the Tendon Sheath > Hallux Valigus.

[24] Campbell S Operative Orthopaedics 4 Volume Set. AMPUTATION OF AN EXTRA TOE (SIMPLE POSTAXIAL POLYDACTYLY) > CONGENITAL HALLUX VARUS.

[25] Aaos Comprehensive Orthopaedic Review 3. Disorders of the First Ray > II. Juvenile Hallux Valgus.

[26] Tachdjian S Pediatric Orthopaedics From The Texas Scottish Rite Hospital For Children E Book. Plate 15.3 Kramer/Barmada Osteotomy of the Base of the Femoral Neck for Slipped Capital Femoral Epiphysis > Hallux Rigidus.

[27] Miller S Review Of Orthopaedics. SECTION 3 ADULT HALLUX VALGUS.

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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.

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