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钮扣孔畸形

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Extensor central-slip injury at the middle finger joint; early splinting prevents the zigzag deformity, established cases need surgery.

Updated Oct 2026
指间关节呈纽扣孔畸形（Boutonniere deformity）的示意图——中间关节屈曲，指尖向后倾斜。
钮扣孔畸形：手指的中间关节持续屈曲，指尖向后倾斜。 Kieran Hirpara 4.0

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。

您的感受

患有钮扣孔畸形时，您手指的中间关节向手掌方向弯曲，而指尖则向相反方向往后弯。手指在中间关节处可能看起来肿胀，该处也可能疼痛。中间关节变得难以伸直，而且您越用力，手指似乎越抗拒。

在需要手指先伸直再弯曲的事务中，问题表现得最明显。捡硬币、握住杯柄端杯子、打字、扣衬衫纽扣或转动钥匙都可能变得别扭。握力本身往往仍然正常，这就是为什么许多人在求助之前会忍受这根手指好几周。

如果畸形是由损伤引起的，中间关节在您用手之后可能会酸痛，而且在早晨手指活动开之前，僵硬可能更明显。在类风湿关节炎中，由于关节内衬在数月间持续发炎肿胀，同样的弯曲姿势会慢慢形成。

有几个信号需要迅速处理。如果您的手指或手变得发热、发红、肿胀和疼痛，尤其是伴有发烧时，请当天前往急诊科。如果某根手指变得苍白、发冷、发白或发紫，或者受伤后突然失去感觉或无法活动，也请当天前往急诊科。如果症状并非如此，而是没有缓解、在数周内逐渐加重、使您在夜间痛醒，或使您无法工作或使用您的手，请咨询您的全科医生（GP）或要求专科医生评估。

实际发生了什么

每根手指的背侧都有一组负责伸直关节的肌腱。可以把它们想象成在手指背侧一个“罩子”下面走行的绳索。伸直中间关节的那根绳索叫做中央腱束，它附着在中间指骨的基底部。另外两根条索叫做侧束，在它两旁走行，帮助伸直中间关节和指尖。

患有钮扣孔畸形时，中央腱束已从中间指骨上撕脱或被拉长。中间关节再也无法被拉直，于是落入弯曲的位置。随后，两条侧束从关节顶部滑脱，向手掌一侧滑移。一旦它们位于关节的转动轴心之下，这些条索就不再伸直中间关节，而是开始使其弯曲，同时把指尖向相反方向往后拉。这就是为什么手指会固定成上述中间关节弯曲、指尖翘起的姿势，也是为什么您每次想伸直它，这些条索似乎都会更用力地与您对抗。

形成这种姿势需要不止一个结构受损。中央腱束、在手指背侧把两条侧束连在一起的韧带，以及“罩子”中将一切固定在位的纤维，都必须受伤，畸形才会形成。单纯的中央腱束撕裂可能只会使中间关节无力，而不出现完整的畸形，这也是早期治疗很重要的原因之一：它可以完全阻止畸形的形成。

同样的结果可以有不同的起因。手指受到撞击或关节背侧的切割伤等损伤可以造成这种畸形，类风湿关节炎的持续炎症也可以，它会慢慢磨穿同样的结构。手指也可能在完全没有肌腱损伤的情况下呈现这种外观，此时问题位于关节的掌侧，这种情况的治疗方法不同，因此首先要弄清楚您属于哪一种。

我们能做什么

Mater Private Hospital Rockhampton 的上肢外科医生 Kieran Hirpara 博士会从适合您病情的最微创方案入手。患者通常由全科医生（GP）转诊至我们的诊所；如果物理治疗师建议您就诊，您仍需获得全科医生的转诊才能符合 Medicare 报销资格。在诊所，我们会采集病史，检查您的手，并在需要时安排影像学检查，以弄清楚问题所在。由于这种畸形可能有几种不同的起因，在进行任何治疗之前，我们会先弄清楚您属于哪一种。

第一步通常是夹板固定和手部治疗。对于新近的损伤，用夹板将中间关节固定在伸直位可以完全阻止畸形的形成，而且越早开始越好：受伤后六周内接受治疗的人，效果好于较晚治疗的人。夹板只把中间关节固定在伸直位。您的指尖、指根关节和其他手指仍保持活动，因为把整根手指都固定不动会使指尖变僵硬。对于已存在一段时间的畸形，我们可能会用石膏固定把中间关节尽可能伸直，随后使用一种夹板三个月，这种夹板允许您在手指活动时弯曲手指。在考虑手术之前，值得先尝试这种方法。

当夹板固定和治疗未能带来足够改善时，可能会考虑手术。手术会重建伸直中间关节的肌腱，有时会取您自己前臂的一小段肌腱作为移植物。在某些情况下，会把滑向手掌一侧的肌腱重新移回到关节上方的正常位置。每种情况的目标都相同：让您能够再次伸直中间关节，并且使用手指时不会卡住或向下弯曲。该手术有单独的介绍页面，在做出任何决定之前，我们会与您详细讨论针对您这根手指的手术涉及哪些内容。

预期情况

预后在很大程度上取决于治疗时机。如果及早发现，钮扣孔畸形往往可以在固定下来之前被阻止。受伤后不久用夹板将中间关节固定在伸直位，可以完全阻止畸形的形成，而在六周内接受治疗的人，效果好于较晚治疗的人。如果不加处理，畸形往往会加重而不是维持不变，因为已经滑离原位的肌腱会不断把手指拉向更弯曲的姿势。一个看似轻微的损伤，可能在数周后导致手指僵硬、固定。

对于已存在一段时间的畸形，非手术治疗仍然有实际作用。先用石膏固定把中间关节尽可能伸直，随后使用一种允许您在用手时弯曲手指的夹板三个月，效果可以很好。当石膏固定能使中间关节接近伸直，并且您在这三个月内戴着夹板积极使用手部时，手指对这种方法反应良好，屈曲功能也会随之恢复。对于拇指损伤，如果在畸形形成之前就开始用夹板将指根关节固定在伸直位，会有帮助。

手术的目标是让您能够再次伸直中间关节。在一组报告的18名接受肌腱移植以矫正长期畸形的患者中，16人取得了良好或优秀的结果。一种让手指早期活动的较新技术，据报道在11个病例中有效。对于出生时就已存在的先天性钮扣孔畸形，手术也可以有所帮助。

坦白地说，并非每一次矫正都能持久。对于受类风湿关节炎影响的手指，在后期阶段仅靠软组织手术可能无法维持矫正，长期结果也较难预测。当畸形复发或持续存在时，采用另一种手术可能是更好的选择。无论起因如何，切合实际的目标是一根您能够伸直并使用的手指，而不是保证手指完全恢复正常。

何时就医

钮扣孔畸形越早处理效果越好，因此值得了解何时应采取行动。如果您的手指受了伤，中间关节无法伸直，或者受伤数天后手指仍处于弯曲和肿胀状态，请去看您的全科医生并要求专科医生评估。夹板固定开始得越早，就越有可能在畸形固定下来之前将其阻止。

有几个信号需要更快的处理。如果您的手指或手变得发热、发红、肿胀和疼痛，尤其是伴有发烧时，请当天前往急诊科。如果某根手指变得苍白、发冷、发白或发紫，或者受伤后突然失去感觉或无法活动，也请当天前往急诊科。如果受伤关节上方的皮肤破损，或手指看起来明显畸形，也请前往急诊科。

如果症状并非如此，而是没有缓解、在数周内逐渐加重、使您在夜间痛醒，或使您无法工作或使用您的手，请咨询您的全科医生（GP）或要求专科医生评估。如果您在下班时间或周末无法联系到诊所，请前往离您最近的急诊科。

深入探讨

Advanced reading: the deeper science (optional)

本节内容超出了您自行做出治疗决策所需的深度。钮扣孔样畸形值得额外阅读，因为对于疼痛、肿胀且弯曲的手指，直觉上的处理方式——让它休息并保持不动——恰恰是证据明确不支持的那一种做法。

早期活动，而非长期固定

一项关于中央滑车损伤治疗的系统综述发现，其证据基础有限，对于开放性和闭合性损伤的不同策略的作用缺乏充分支持 [1]。在此局限性范围内，来自个体研究的证据初步支持早期活动，不支持长期固定 [1]。

这一点值得明确陈述，因为它违背了本能反应。其区别在于保护愈合中的中央滑车（这需要保持中间关节伸直）与固定整个手指（这会导致指尖关节在伸直位僵硬，并使整个手指变得僵硬）。夹板的目的是固定一个关节，同时让其他关节保持活动。

为何畸形会进行性加重而非保持静止

钮扣孔畸形（Boutonnière deformity）是一种进行性畸形，这一点较为罕见且值得深入理解。中央腱束附着于中节指骨基底，负责伸直中间关节（近端指间关节）。当其功能失效时，该关节陷入屈曲位，而两条侧腱束——正常情况下走行于关节轴线上方——则滑移至轴线下方。

一旦侧腱束位于轴线下方，原本辅助伸直中间关节的同一组肌腱便开始使其屈曲，同时将指尖拉入过伸位。因此，该畸形具有自我强化特性：任何试图伸直手指的努力都会使当前维持其屈曲位的结构进一步收紧。这正是为何看似轻微的外伤可能在数周后导致固定性畸形，以及为何简单夹板固定的有效窗口期仅限于早期。

非钮扣孔样畸形

手指可在完全没有中央滑车损伤的情况下呈现相同的姿势，且治疗方案截然不同。钮扣孔样畸形与假性钮扣孔样畸形在病理解剖、诊断及治疗上均存在差异 [2]，其中假性类型源于中节指间关节的掌板损伤，此时远端指间关节保留正常的被动屈曲功能，而非被牵拉至过伸位。

床旁鉴别二者关键在于远端指间关节。在真性钮扣孔样畸形中，远端指间关节处于过伸位且抵抗屈曲，尤其在中节指间关节伸直时更为明显；而在假性钮扣孔样畸形中，远端指间关节可自由屈曲。若将假性钮扣孔样畸形误当作真性畸形进行夹板固定，则针对了错误的关节。

它属于一类由肌腱失效部位所定义的损伤

钮扣指畸形（Boutonnière）与锤状指（mallet finger）及矢状带损伤（sagittal band injury）并列为三种闭合性伸肌机制损伤之一，这些损伤根据机制失效的分区（zone）进行分类 [3]。这三种损伤均可能在受伤后数天内表现为肿胀的手指并处于异常姿势，且每种损伤都需要不同的夹板固定位置，这正是为何在决定进行数周夹板固定之前，值得做出明确诊断的实际原因。

参考文献

[1] Geoghegan L, Wormald JCR, Adami RZ, Rodrigues JN. 中央滑车伸肌腱损伤：治疗方法的系统综述。J Hand Surg Eur Vol. 2019;44(8):825-32. https://doi.org/10.1177/1753193419845311

[2] Hanson ZC, Thompson RG, Andrews JR, Lourie GM. 纽扣孔畸形与假纽扣孔畸形：病理解剖、诊断与治疗。J Hand Surg Am. 2023;48(5):489-97. https://doi.org/10.1016/j.jhsa.2022.10.019

[3] Lin JD, Strauch RJ. 闭合性软组织伸肌装置损伤（锤状指、纽扣孔畸形及矢状带损伤）。J Hand Surg Am. 2014;39(5):1005-11. https://doi.org/10.1016/j.jhsa.2013.11.018

Reviewed by Dr Kieran Hirpara · 10 June 2026.

Talk to your treating clinician for advice specific to you.

For an appointment with the CQ Hand + Upper Limb team, ask your GP about a referral or visit www.cqupperlimb.com.

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.

Overview

  • A staged technique for the repair of traumatic boutonniere deformity allows the surgeon to divide the deformity into various categories and use the operative procedure indicated for each particular problem, often avoiding unnecessary surgery [1].
  • Differentiating a true boutonniere deformity from a pseudoboutonniere injury is critical in determining clinical management [2].
  • A retrospective study of fifty-four longstanding post-burn boutonnière deformities was carried out to evaluate the problems associated with the surgical procedures [3].
  • An understanding of the anatomy, clinical presentation, treatment options, and expected outcomes is crucial for optimal treatment of posttraumatic boutonnière and swan neck deformities [4].
  • Early treatment of central slip injuries can prevent the deformity [5].
  • Transection of the terminal extensor tendon is a useful procedure for salvage of the boutonniere deformity [6].
  • No boutonniere deformities were produced in a series of 20 patients who had chronic mallet finger deformity treated with central slip tenotomy [7].
  • Reconstruction of the central slip by the transverse retinacular ligament is not indicated for boutonnière deformities with severe contracture of the lateral band [8].
  • The best indication for reconstruction of the central slip by the transverse retinacular ligament is in cases in which the central slip is defective and conservative treatment is not effective [8].
  • Similar results occurred for chronic boutonniere deformity using serial casting for adequate extension followed by 3 months of relative motion flexion (RMF) orthotic use, which should be attempted prior to surgical intervention [9].
  • A new surgical technique with early mobilization is an effective and simplified treatment of Boutonniere deformity [10].
  • The natural history of the boutonnière deformity in rheumatoid arthritis is outlined, and a simple method of repair is described [11].
  • Chronic boutonniere deformity will respond to relative motion flexion splinting if serial casting can place the proximal interphalangeal joint in less than -20° extension, and the patient actively uses the hand in a relative motion flexion orthosis for 3 months, recovering flexion [12].
  • The Y-shaped tendon graft can be a useful procedure for the correction of chronic boutonniere deformity [13].
  • In a patient series of 18 patients, the Y-shaped tendon graft provided good or excellent results in 16 patients [13].
  • Extension splinting of the metacarpophalangeal (MP) joint may be effective if traumatic thumb injuries are treated before development of a boutonnière deformity [14].
  • Congenital boutonniere deformity is understood as various embryonic developmental failures [15].
  • A reliable surgical option for congenital boutonniere deformity involves central slip reconstruction [15].
  • Extensor tenotomy to correct a boutonnière deformity of long standing markedly lessened disability with restoration of flexion of the distal joint [16].
  • In chronic boutonniere deformity, when the lateral bands are deficient or damaged, the cross-lateral band reconstruction technique using palmaris longus autograft is a treatment option with satisfactory results [17].
  • Extension splinting may be effective if traumatic thumb injuries are treated before deformity development [18].
  • Surgical treatment with advancement of the extensor pollicis brevis tendon and imbrication of the dorsoradial capsule is necessary once a traumatic thumb boutonnière deformity is established [18].
  • The prevalence of boutonnière deformity without rheumatoid arthritis or trauma is approximately 13% [19].
  • Current concepts relating to the presentation and treatment of closed soft tissue injuries of the extensor mechanism in zones I, III, and V, commonly known as mallet finger, boutonniere deformities, and sagittal band injuries, are summarized [20].
  • Long-term results following soft tissue reconstruction for boutonniere finger deformity in rheumatoid arthritis are unreliable [24].
  • Recurrent or persistent deformity in rheumatoid arthritis is best treated with a salvage procedure [24].

Anatomy & Pathophysiology

Extensor Mechanism Anatomy

  • The extensor mechanism of the finger at the level of the proximal interphalangeal (PIP) joint consists of both intrinsic and extrinsic contributions [28].
  • The extensor tendon entering the digit is the continuation of the extensor digitorum communis (EDC), with contributions from the extensor indicis proprius in the index finger and the extensor digiti quinti in the small finger [28].
  • In 30% of cases, the EDC has a separate insertion into the base of the proximal phalanx, but extension of the metacarpophalangeal (MP) joint typically occurs through the pull of the sagittal bands [28].
  • The principal bony insertion of the extrinsic digital extensors is on the dorsal proximal aspect of the middle phalanx [32].
  • Metacarpophalangeal joint extension is provided by extrinsic extensor force transmitted through the sagittal bands [32].
  • Distal interphalangeal joint extension is achieved through conjoined lateral bands composed of tendinous slips from both extrinsic and intrinsic tendons [32].
  • The deep head of each dorsal interosseous muscle forms a lateral tendon, or lateral band, at the level of the MP joint [41].
  • At the level of the middle of the proximal phalanx, transverse fibers arch dorsally from each lateral band to join over the dorsum of the finger, flexing the proximal phalanx [41].
  • Oblique fibers (spiral fibers) from the lateral bands sweep over the distal third of the proximal phalanx to insert onto the lateral tubercles at the base of the middle phalanx, extending the middle phalanx [41].
  • The lateral bands are joined by the lateral slips of the extensor tendon to form the conjoined lateral band [41].
  • The two conjoined lateral bands to each finger unite at the distal third of the middle phalanx to form the terminal tendon, which inserts at the base of the distal phalanx to extend it [41].
  • The volar interossei form the ulnar lateral band of the index finger and the radial lateral band of the ring and little fingers [41].
  • The flexor digiti quinti brevis is structurally and functionally similar to the deep head of the dorsal interossei, forming the ulnar lateral band of the little finger [41].

Pathophysiology & Biomechanics

  • A boutonniere deformity requires subluxation of the lateral bands volar to the axis of rotation of the PIP joint [22].
  • Damage to the central slip alone does not cause a boutonniere deformity [22].
  • A boutonniere deformity occurs only when the central slip, triangular ligament, and transverse and oblique fibers of the interosseous hood are all damaged [22].
  • Detachment of the central slip from the middle phalanx produces a decrease in extension of the PIP joint [22].
  • When the transverse and oblique fibers of the interosseous hood are divided in addition to the central slip, extension at the PIP joint is further decreased [22].
  • Early treatment of central slip injuries can prevent the development of the deformity [5].
  • The extensor mechanism is a complex structure that demands a delicate balance from intrinsic and extrinsic tendons of the hand [28].
  • Injury to the extensor mechanism can disrupt this delicate balance, leading to significant sequelae [28].
  • Understanding the anatomy, clinical presentation, treatment options, and expected outcomes is crucial for optimal treatment of posttraumatic boutonnière and swan neck deformities [4].

Classification

  • A staged management plan allows the surgeon to divide traumatic boutonniere deformity into various categories and use the operative procedure indicated for each particular problem [1].
  • The choice of surgical procedure for rheumatoid boutonniere deformity is dependent on accurate staging of the deformity, which is based on the flexibility of the proximal interphalangeal joint and the state of the articular cartilage [23].
  • In a cadaveric model, damage to the central slip alone does not cause a boutonniere deformity [22].
  • The boutonniere deformity requires subluxation of the lateral bands volar to the axis of rotation of the PIP joint [22].
  • In a cadaveric model, the central slip, triangular ligament, and oblique fibers need to all be damaged to cause subluxation of the lateral bands which leads to an acute boutonniere deformity [29].
  • Anterior dislocation of the proximal interphalangeal joint is associated with ruptures of the central slip of the extensor mechanism and results in boutonnière deformity unless repaired [27].
  • The incidence of uncorrectable swan-neck and boutonniere deformities is estimated to be between 8% and 16% during the first 2 years after the onset of systemic disease in rheumatoid arthritis [23].
  • The prevalence of boutonniere deformities in patients with established rheumatoid arthritis is approximately 36% [23].

Clinical Presentation

Diagnostic Differentiation and Classification

  • The surgeon can divide the boutonniere deformity into various categories to use the operative procedure indicated for each particular problem, often avoiding unnecessary surgery [1].

Etiology and Pathomechanics

  • The cause of boutonniere deformity in rheumatoid arthritis is chronic synovitis of the proximal interphalangeal joint [23].
  • Combined injury of the central slip, triangular ligament, and transverse and oblique fibers of the interosseous hood causes a boutonniere deformity [22].

Prevalence and Natural History

  • A swan-neck or boutonniere deformity occurs in approximately half of patients with rheumatoid arthritis [23].
  • The incidence of uncorrectable swan-neck and boutonniere deformities is estimated to be between 8% and 16% during the first 2 years after the onset of systemic disease [23].
  • The prevalence of finger deformities in patients with established rheumatoid arthritis is approximately 36% for boutonniere deformities [23].
  • The natural history of the boutonnière deformity in rheumatoid arthritis is outlined in the literature [11].

Clinical Assessment and Testing

  • The central slip tenodesis test detects disruption of the central slip before the boutonniere deformity becomes established [34].
  • The central slip tenodesis test is applicable in uncooperative children and unconscious patients [34].
  • Treating swan neck and boutonniere deformities of the PIP joint requires understanding the cause, biomechanical changes, and articular status [26].

Investigations

Clinical Examination and Diagnostic Tests

  • A careful physical examination is essential to direct care and future testing if indicated [31].
  • Diagnostic tests such as imaging and serum laboratory studies are useful in the determination of pathology but can be expensive, time consuming, and often nonspecific [31].

Biomechanical and Pathomechanical Assessment

Imaging and Advanced Modalities

  • A computational 3D model validation reassures the reliability of research in understanding the pathomechanics of boutonniere deformity [21].

Treatment

Non-Operative

  • Early treatment of central slip injuries can prevent the development of boutonniere deformity [5].
  • Extension splinting of the metacarpophalangeal joint may be effective for traumatic thumb boutonniere deformity if treated before the deformity develops [14].
  • Extension splinting may be effective for traumatic thumb boutonniere deformity if treated before deformity development [18].
  • Chronic boutonniere deformity responds to relative motion flexion splinting if serial casting places the proximal interphalangeal joint in less than -20° extension and the patient actively uses a relative motion flexion orthosis for 3 months [12].
  • Serial casting for adequate extension followed by 3 months of relative motion flexion orthotic use should be attempted prior to surgical intervention for chronic boutonniere deformity [9].
  • The use of relative motion flexion orthoses is effective in increasing active distal interphalangeal joint flexion and improving proximal interphalangeal joint extension in patients with Burton stage 1 chronic boutonniere deformity [30].
  • Conservative treatment of closed central slip injuries involves immobilization of the proximal interphalangeal, distal interphalangeal, and metacarpophalangeal joints in full extension for four weeks followed by a Capener spring splint for two further weeks [92].
  • In a review of 115 central slip injuries, 17 of 24 patients treated conservatively achieved an outcome of less than a 20° extension deficit at the proximal interphalangeal joint and more than 80% return of proximal interphalangeal joint flexion [92].
  • Patients treated for central slip injuries within six weeks of injury had better outcomes than those treated later [92].

Operative

  • A staged technique allows the surgeon to divide traumatic boutonniere deformity into various categories and use the operative procedure indicated for each particular problem, often avoiding unnecessary surgery [1].
  • Reconstruction of the central slip by the transverse retinacular ligament is best indicated in cases in which the central slip is defective and conservative treatment is not effective [8].
  • A simple method of repair for the rheumatoid boutonnière deformity is described in the literature [11].
  • In a patient series, the Y-shaped tendon graft provided good or excellent results in 16 of 18 patients with chronic boutonniere deformity [13].
  • Surgical treatment with advancement of the extensor pollicis brevis tendon and imbrication of the dorsoradial capsule is necessary once a traumatic boutonnière deformity of the thumb is established [18].
  • The cross-lateral band reconstruction technique using palmaris longus autograft is a treatment option with satisfactory results for chronic boutonniere deformity when the lateral bands are deficient or damaged [17].
  • A reliable surgical option involving central slip reconstruction is suggested for the congenital form of boutonniere deformity [15].
  • A simple staged procedure using a central slip facilitation device is a valid alternative in the management of severe Dupuytren's proximal interphalangeal joint contracture, demonstrating reliable, reproducible correction of the deformity and acceptable patient outcomes [38].

Complications

  • In a patient series of 18 patients, the Y-shaped tendon graft provided good or excellent results in 16 of 18 patients for the correction of chronic boutonniere deformity [13].
  • Extension splinting of the MP joint may be effective if traumatic thumb injuries are treated before development of a boutonnière deformity [14].
  • The case extends understanding of congenital boutonniere deformity as various embryonic developmental failures and suggests a reliable surgical option involving central slip reconstruction [15].
  • Surgical treatment with advancement of the extensor pollicis brevis tendon and imbrication of the dorsoradial capsule is necessary once a boutonnière deformity is established in the thumb [18].
  • This article summarizes current concepts relating to the presentation and treatment of closed soft tissue injuries of the extensor mechanism in zones I, III, and V, commonly known as mallet finger, boutonniere deformities, and sagittal band injuries [20].
  • This validation reassures the reliability of the research in understanding the pathomechanics of boutonniere deformity [21].
  • In a cadaver model, detachment of the central slip from the middle phalanx produced a decrease in extension of the PIP joint [22].
  • When the transverse and oblique fibers of the interosseous hood were also divided after central slip detachment, extension at the PIP joint was further decreased [22].
  • A boutonniere deformity occurred only when all 3 structures (central slip, transverse and oblique fibers of the interosseous hood, and triangular ligament) were damaged [22].
  • Division of the central slip leads to loss of extension at the PIP joint [22].
  • The prevalence of finger deformities in patients with established rheumatoid arthritis is approximately 14% for swan-neck deformities and 36% for boutonniere deformities [23].
  • In the later stages of both swan-neck and boutonniere deformities, soft-tissue procedures alone may not result in lasting operative correction [23].
  • Long-term results following soft tissue reconstruction are unreliable [24].
  • Recurrent or persistent deformity is best treated with a salvage procedure [24].
  • Treating swan neck and boutonniere deformities of the PIP joint is a difficult challenge that requires understanding the cause, biomechanical changes, and articular status [26].
  • Anterior dislocation of the proximal interphalangeal joint is associated with ruptures of the central slip of the extensor mechanism [27].
  • Anterior dislocation of the proximal interphalangeal joint results in boutonnière deformity unless repaired [27].

Recovery

Non-Operative Management

  • Serial casting for adequate extension followed by 3 months of relative motion flexion (RMF) orthotic use should be attempted prior to surgical intervention for chronic boutonniere deformity [9].
  • Chronic boutonniere deformity responds to relative motion flexion splinting if serial casting places the proximal interphalangeal joint in less than -20° extension and the patient actively uses the hand in a relative motion flexion orthosis for 3 months, recovering flexion [12].
  • Extension splinting of the metacarpophalangeal joint may be effective for traumatic thumb boutonniere injuries if treated before the development of a boutonnière deformity [14].

Operative Management

  • A staged technique allows the surgeon to divide the traumatic boutonniere deformity into various categories and use the operative procedure indicated for each particular problem, often avoiding unnecessary surgery [1].
  • The Y-shaped tendon graft provided good or excellent results in 16 of 18 patients for the correction of chronic boutonniere deformity [13].
  • Reconstruction of the central slip by the transverse retinacular ligament is indicated in cases in which the central slip is defective and conservative treatment is not effective, but is not indicated for boutonnière deformities with severe contracture of the lateral band [8].
  • A simple method of repair for the correction of the rheumatoid boutonnière deformity has been described [11].
  • A new surgical technique with early mobilization for chronic boutonniere deformity was reported to be an effective and simplified treatment in 11 cases [10].
  • Central slip reconstruction is a reliable surgical option for the congenital form of boutonniere deformity [15].

Outcomes and Prognosis

  • Early treatment of central slip injuries can prevent the boutonniere deformity [5].
  • Long-term results following soft tissue reconstruction for boutonniere finger deformity in rheumatoid arthritis are unreliable, and recurrent or persistent deformity is best treated with a salvage procedure [24].
  • In the later stages of rheumatoid boutonniere deformities, soft-tissue procedures alone may not result in lasting operative correction [23].
  • A patient with boutonniere deformity of the second toe after planter dislocation of the proximal interphalangeal joint reported neither deformity nor difficulty when last seen 22 months after the operation [95].

Key Evidence

  • [L4] With this plan of management, the surgeon is able to divide the boutonniere deformity into various categories and then use the operative procedure indicated for each particular problem, often avoiding unnecessary surgery. [1] (10.1016/s0363-5023(83)80009-4)
  • [L5] Differentiating a true boutonniere deformity from a pseudoboutonniere injury is critical in determining clinical management. [2] (10.1016/j.jhsa.2022.10.019)
  • [L4] A retrospective study of fifty-four longstanding post-burn boutonnière deformities was carried out to evaluate the problems associated with the surgical procedures. [3] (10.1016/0266-7681(86)90006-9)
  • [L5] An understanding of the anatomy, clinical presentation, treatment options, and expected outcomes is crucial for optimal treatment of posttraumatic boutonnière and swan neck deformities. [4] (10.5435/jaaos-d-14-00272)
  • [L5] The paper outlines the anatomy, pathoanatomy, and treatment concepts for boutonniere deformity, emphasizing that early treatment of central slip injuries can prevent the deformity. [5] (10.1016/s0749-0712(21)00060-3)
  • [L4] Transection of the terminal extensor tendon is a useful procedure for salvage of the boutonniere deformity. [6] (10.1016/s0749-0712(21)00065-2)
  • [L4] No boutonniere deformities were produced in this series of 20 patients who had chronic mallet finger deformity. [7] (10.1016/s0363-5023(87)80205-8)
  • [L4] This procedure is not indicated for boutonnière deformities with severe contracture of the lateral band; its best indication is in cases in which the central slip is defective and conservative treatment is not effective. [8] (10.1016/0266-7681(90)90080-n)
  • [L4] Similar results occurred for chronic boutonniere deformity using serial casting for adequate extension followed by 3 months of RMF orthotic use, which should be attempted prior to surgical intervention. [9] (10.1016/j.jht.2023.02.005)
  • [L4] Our technique is an effective and simplified treatment of Boutonniere deformity. [10] (10.1097/bth.0000000000000152)
  • [L4] The natural history of the boutonnière deformity in rheumatoid arthritis is outlined, and a simple method of repair is described. [11] (10.2106/00004623-196951070-00009)
  • [L4] Chronic boutonniere deformity will respond to relative motion flexion splinting if serial casting can place the proximal interphalangeal joint in less than -20° extension, and the patient actively uses the hand in a relative motion flexion orthosis for 3 months, recovering flexion. [12] (10.1097/sap.0000000000002307)
  • [L4] The Y-shaped tendon graft can be a useful procedure for the correction of chronic boutonniere deformity; in our patient series, this provided good or excellent results in 16 of 18 patients. [13] (10.1016/j.jhsa.2021.01.003)
  • [L4] Extension splinting of the MP joint may be effective if these injuries are treated before development of a boutonnière deformity. [14] (10.1016/s0266-7681(00)80024-8)
  • [Case_report] The case extends understanding of congenital boutonniere deformity as various embryonic developmental failures and suggests a reliable surgical option involving central slip reconstruction. [15] (10.1016/j.jhsa.2014.05.030)
  • [L4] In chronic boutonniere deformity, when the lateral bands are deficient or damaged, the cross-lateral band reconstruction technique using palmaris longus autograft is a treatment option with satisfactory results. [17] (10.1016/j.jhsa.2017.04.010)
  • [L4] Extension splinting may be effective if treated before deformity development, but surgical treatment with advancement of the extensor pollicis brevis tendon and imbrication of the dorsoradial capsule is necessary once a boutonnière deformity is established. [18] (10.1054/jhsb.1999.0303)
  • [L3] The prevalence of boutonnière deformity without rheumatoid arthritis or trauma is approximately 13%. [19] (10.1177/1753193417704610)
  • [L5] This article summarizes current concepts relating to the presentation and treatment of closed soft tissue injuries of the extensor mechanism in zones I, III, and V, commonly known as mallet finger, boutonniere deformities, and sagittal band injuries. [20] (10.1016/j.jhsa.2013.11.018)
  • [L5] This validation reassures the reliability of the research in understanding the pathomechanics of boutonniere deformity. [21] (10.1186/s13018-025-06329-3)
  • [L5] [22] (10.1016/j.jhsa.2017.07.011)
  • [L5] [23] (10.5435/00124635-199903000-00002)
  • [L5] Long-term results following soft tissue reconstruction are unreliable, and recurrent or persistent deformity is best treated with a salvage procedure. [24] (10.1016/j.jhsa.2011.05.029)
  • [L4] Treating swan neck and boutonniere deformities of the PIP joint is a difficult challenge that requires understanding the cause, biomechanical changes, and articular status. [26] (10.1016/j.hcl.2017.12.006)
  • [Paper] [28] (10.1016/j.hcl.2012.05.044)
  • [Paper] In a cadaveric model, the central slip, triangular ligament, and oblique fibers need to all be damaged to cause subluxation of the lateral bands which leads to an acute boutonniere deformity. [29] (10.1016/s0363-5023(12)60014-8)
  • [L4] The use of RMFO is effective in increasing active distal interphalangeal joint flexion and improving PIP extension in patients with Burton stage 1 chronic boutonniere deformity. [30] (10.1016/j.jhsa.2022.08.007)
  • [Paper] The test detects disruption of the central slip before the boutonniere deformity becomes established and is applicable in uncooperative children and unconscious patients. [34] (10.1016/0266-7681(94)90057-4)
  • [L4] The simple staged procedure is a valid alternative in the management of severe Dupuytren's PIPJ contracture, demonstrating reliable, reproducible correction of the deformity and acceptable patient outcomes. [38] (10.1177/1753193412439673)
  • [L4] [92] (10.1177/1758998318822663)
  • [Case_report] The patient reported neither deformity nor difficulty when last seen 22 months after the operation. [95] (10.1007/s00402-009-0816-x)

References

[1] A staged technique for the repair of the traumatic boutonniere deformity. The Journal of Hand Surgery. 1983. DOI: 10.1016/s0363-5023(83)80009-4

[2] Boutonniere Versus Pseudoboutonniere Deformities: Pathoanatomy, Diagnosis, and Treatment. The Journal of Hand Surgery. 2023. DOI: 10.1016/j.jhsa.2022.10.019

[3] Reconstructive surgery of the post-burn boutonnière deformity. The Journal of Hand Surgery: Journal of the British Society for Surgery of the Hand. 1986. DOI: 10.1016/0266-7681(86)90006-9

[4] Posttraumatic Boutonnière and Swan Neck Deformities. Journal of the American Academy of Orthopaedic Surgeons. 2015. DOI: 10.5435/jaaos-d-14-00272

[5] BOUTONNIERE DEFORMITY. Hand Clinics. 1995. DOI: 10.1016/s0749-0712(21)00060-3

[6] TREATMENT OF THE CHRONIC BOUTONNIERE DEFORMITY BY EXTENSOR TENOTOMY. Hand Clinics. 1995. DOI: 10.1016/s0749-0712(21)00065-2

[7] Central slip tenotomy for chronic mallet finger deformity. The Journal of Hand Surgery. 1987. DOI: 10.1016/s0363-5023(87)80205-8

[8] Reconstruction of the Central Slip by the Transverse Retinacular Ligament for Boutonnière Deformity. Journal of Hand Surgery. 1990. DOI: 10.1016/0266-7681(90)90080-n

[9] The relative motion concept in acute and chronic boutonniere deformity: Invited commentary. Journal of Hand Therapy. 2023. DOI: 10.1016/j.jht.2023.02.005

[10] Chronic Boutonniere Deformities, Supple, or Stiff: A New Surgical Technique With Early Mobilization in 11 Cases. Techniques in Hand & Upper Extremity Surgery. 2017. DOI: 10.1097/bth.0000000000000152

[11] Correction of the Rheumatoid Boutonnière Deformity. The Journal of Bone & Joint Surgery. 1969. DOI: 10.2106/00004623-196951070-00009

[12] A Paradigm Shift in Managing Acute and Chronic Boutonniere Deformity. Annals of Plastic Surgery. 2020. DOI: 10.1097/sap.0000000000002307

[13] Y-Shaped Tendon Graft—A Technique in the Reconstruction of Posttraumatic Chronic Boutonniere Deformity. The Journal of Hand Surgery. 2021. DOI: 10.1016/j.jhsa.2021.01.003

[14] Traumatic Boutonnière Deformity of the Thumb. Journal of Hand Surgery. 2000. DOI: 10.1016/s0266-7681(00)80024-8

[15] Restoration of the Central Slip in Congenital Form of Boutonniere Deformity: Case Report. The Journal of Hand Surgery. 2014. DOI: 10.1016/j.jhsa.2014.05.030

[16] Extensor Tenotomy for Chronic Boutonniere Deformity of the Finger: REPORT OF TWO CASES.. The Journal of Bone and Joint Surgery. American Volume. 1965.

[17] Chronic Boutonniere Deformity: Cross-Lateral Band Technique Using Palmaris Longus Autograft. The Journal of Hand Surgery. 2017. DOI: 10.1016/j.jhsa.2017.04.010

[18] TRAUMATIC BOUTONNIÈRE DEFORMITY OF THE THUMB. The Journal of Hand Surgery: Journal of the British Society for Surgery of the Hand. 2000. DOI: 10.1054/jhsb.1999.0303

[19] Thumb boutonnière deformity without rheumatoid arthritis or trauma. Journal of Hand Surgery (European Volume). 2017. DOI: 10.1177/1753193417704610

[20] Closed Soft Tissue Extensor Mechanism Injuries (Mallet, Boutonniere, and Sagittal Band). The Journal of Hand Surgery. 2014. DOI: 10.1016/j.jhsa.2013.11.018

[21] Assessment of the ligamentous stress distribution in the pathomechanics of the boutonniere deformity through a computational 3D model. Journal of Orthopaedic Surgery and Research. 2025. DOI: 10.1186/s13018-025-06329-3

[22] Biomechanics of the Acute Boutonniere Deformity. The Journal of Hand Surgery. 2018. DOI: 10.1016/j.jhsa.2017.07.011

[23] Operative Correction of Swan-Neck and Boutonniere Deformities in the Rheumatoid Hand. Journal of the American Academy of Orthopaedic Surgeons. 1999. DOI: 10.5435/00124635-199903000-00002

[24] Treatment of Boutonniere Finger Deformity in Rheumatoid Arthritis. The Journal of Hand Surgery. 2011. DOI: 10.1016/j.jhsa.2011.05.029

[26] Treating the Proximal Interphalangeal Joint in Swan Neck and Boutonniere Deformities. Hand Clinics. 2018. DOI: 10.1016/j.hcl.2017.12.006

[27] Anterior dislocation of the proximal interphalangeal joint. A cause of rupture of the central slip of the extensor mechanism.. The Journal of bone and joint surgery. American volume. 1970.

[28] Boutonnière and Pulley Rupture in Elite Athletes. Hand Clinics. 2012. DOI: 10.1016/j.hcl.2012.05.044

[29] Biomechanics of the Acute Boutonniere Deformity. The Journal of Hand Surgery. 2012. DOI: 10.1016/s0363-5023(12)60014-8

[30] The Use of Relative Motion Flexion Orthoses for Chronic Boutonniere Deformity. The Journal of Hand Surgery. 2024. DOI: 10.1016/j.jhsa.2022.08.007

[31] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Anatomy, Evaluation, Clinical Examination, and Imaging > Evaluation and Clinical Examination: Current Concepts.

[32] A Lange Medical Book Current Diagnosis Treatment In Orthopedics Fifth Edition. 9Hand Surgery > Image DISORDERS OF THE MUSCULATURE OF THE HAND.

[34] The Central Slip Tenodesis Test for Early Diagnosis of Potential Boutonnière Deformities. Journal of Hand Surgery. 1994. DOI: 10.1016/0266-7681(94)90057-4

[38] Management of severe Dupuytren’s contracture of the proximal interphalangeal joint with use of a central slip facilitation device. Journal of Hand Surgery (European Volume). 2012. DOI: 10.1177/1753193412439673

[41] Green S Operative Hand Surgery. Interosseous and Hypothenar Muscles.

[92] Therapeutic management of closed central slip injuries: Outcome of a service evaluation. Hand Therapy. 2019. DOI: 10.1177/1758998318822663

[95] Boutonniere deformity of the second toe after planter dislocation of proximal interphalangeal joint: a case report. Archives of Orthopaedic and Trauma Surgery. 2009. DOI: 10.1007/s00402-009-0816-x

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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.

Creative Commons may be contacted at creativecommons.org.