Boutonnière Deformity Info In-depth Evidence
Reviewed by Dr Kieran Hirpara, Specialist Orthopaedic Surgeon Last reviewed
What you're feeling
A boutonnière deformity changes the way one of your fingers bends. The middle joint of the finger stays bent down, and the end joint points up instead of bending. It happens when a small, flat tendon on the back of the finger (the central slip) stops doing its job. That tendon normally straightens the middle joint. When it is torn, stretched or worn through, the finger can no longer straighten there.
The finger can be painful, and it can make your hand much harder to use. Tasks that need a straight finger become the hard ones. Putting your hand into a glove, typing, holding a pen or picking up coins can all feel awkward or uncomfortable. Anything that presses the bent joint, like gripping a steering wheel or carrying a shopping bag by the handle, may make the pain worse. Resting the hand and keeping the finger still usually settles it down.
This deformity is common in people with rheumatoid arthritis, where ongoing swelling inside the middle joint (synovitis) slowly wears away that tendon. About 36% of people with established rheumatoid arthritis have a boutonnière deformity, and around half develop a boutonnière or swan-neck finger deformity. It can also follow an injury, such as a cut or a hard blow to the back of the finger that damages the central slip.
The swelling and pain often follow a pattern. The joint may feel stiff and sore on waking, then loosen a little as you start moving. After a busy day using the hand, the finger can ache and feel more bent than usual. Night-time throbbing in the joint is also common when the finger has been overworked.
One thing worth knowing: catching this early matters. If a central slip injury is treated soon after it happens, the deformity can often be prevented from developing at all.
What's actually happening
Think of the tendon on the back of your finger as a rope that runs along the top and splits into strands near the middle joint. One strand, the central slip, plugs into the middle bone and straightens that joint. Two other strands run up either side of it. Normally all three work together, held in place over the joint by thin sheets of tissue, like guy ropes holding a tent pole upright.
When the finger is injured, or when rheumatoid arthritis wears the tendon away from inside the joint, the central slip can tear off or stretch out. Once it lets go, the two side strands slip underneath the joint instead of running over the top. From there they pull the middle joint down into a bent position rather than straightening it. That is why your finger sits bent at the middle joint and points up at the end.
It takes more than one damaged part to produce this. The central slip, the sheets of tissue holding the strands in place, and some of the fibres around them all need to be affected before the strands actually slide out of position. That is also why a finger can feel like it is snapping or catching at the middle joint early on, before the full deformity sets in.
One more thing worth knowing. Once the deformity has been there a long time, the joint itself stiffens and adapts to its bent position. Even with treatment, a few degrees of lost straightening at the middle joint can remain. This is why early treatment matters so much, as the section above explains.
What we can do about it
Dr Kieran Hirpara, an upper-limb surgeon at Mater Private Hospital Rockhampton, starts with the least invasive options that suit your condition. Patients are generally referred to our clinic by their GP; if a physiotherapist has suggested you see us, you will still need a referral from your GP in order to be eligible for the Medicare rebate. At your first visit we take a history, examine your finger, and arrange imaging only where it will change the plan. A careful examination is what points us towards the right tests and the right treatment.
For a deformity that has been there a while, we usually begin with splinting. Once the casts have done their work, you wear a splint that holds the finger in a position that lets you keep using your hand. You wear it for 3 months. This works when the casts have brought the middle joint to less than -20° of extension, meaning it can straighten past a point 20 degrees short of fully straight, and you use the splint actively throughout. Starting treatment within 6 weeks of the injury makes a real difference to how much movement you get back. For a fresh central slip injury, we hold the finger joints in full extension (completely straight) for four weeks, then use a spring-loaded splint for two further weeks. Most of that time you can still use your hand for light tasks.
When splinting has not given you enough straightening, surgery is the next step. We consider it once the tendon has been damaged beyond what a splint can fix, or when the deformity has become fixed in place. The operation rebuilds the tendon mechanism at the back of your finger so it can straighten the middle joint again. Where the side strands of tendon are worn or damaged, we can rebuild them using a strip of tendon from your own wrist. The details of each operation have their own page, and we will talk through which one suits your finger before any decision is made.
What to expect
How things go depends a lot on how quickly the finger is treated. If a fresh central slip injury is splinted early, the deformity can often be prevented from developing at all. If it is left alone, the middle joint usually stays bent and can become fixed in that position over time. Once the deformity has been there a long while, even good treatment may leave the finger a few degrees short of fully straight.
For a deformity that has already settled in, the first steps are casts to straighten the middle joint, followed by 3 months of wearing a splint while you keep using your hand. This works when the casts can bring the joint to less than -20° of extension, meaning it straightens past a point 20 degrees short of fully straight. You need to use your hand actively in that splint throughout the 3 months to get your bending movement back. It is a slow process, and it asks something of you: the splint only helps if you actually work the finger while wearing it.
When splinting has done all it can, surgery is the next step. Where the side strands of tendon are worn or damaged, a strip of tendon from your own wrist can be used to rebuild them. In people who have had that operation for a long-standing deformity, results were good or excellent in 16 of 18 patients. Another option for long-standing deformity is cutting the tendon at the end joint, which markedly lessened disability and restored bending at that joint in the people who had it.
A few honest cautions. In the later stages of this deformity, soft-tissue operations alone may not hold the correction permanently. And if you have rheumatoid arthritis, finger deformities can keep developing as the underlying condition progresses, so your treatment plan will weigh up how fixed the joint is, how it moves, and the state of the joint surface. None of this means surgery cannot help. It means the goal is a finger that works better, not a promise of a perfectly straight one.
When to see someone
See your GP if a finger has started sitting bent at the middle joint and will not straighten, especially if you have rheumatoid arthritis. Ask for a specialist review if the middle joint is painful, catching or snapping, or if the finger is getting harder to use for everyday tasks. These changes can creep up slowly, so it is easy to put them down to overuse. The timing matters: starting treatment within 6 weeks of an injury makes a real difference to how much movement you get back, and once a deformity has been there a long time it becomes much harder to correct. If you notice one finger bending down at the middle joint while the end joint points up, do not wait for it to settle on its own.
In more depth
Advanced reading: the deeper science (optional)
This section goes further than you need for your own treatment decisions. Boutonnière deformity is worth the extra reading because the instinctive treatment for a painful, swollen, bent finger, rest it and keep it still, is the one thing the evidence specifically does not support.
Early mobilisation, not prolonged immobilisation
A systematic review of treatments for central slip injury found the evidence base limited, with the roles of different strategies for both open and closed injuries not well supported [1]. Within that limitation, the evidence from individual studies tentatively supports early mobilisation and does not support prolonged immobilisation [1].
That is worth stating plainly because it runs against the reflex. The distinction is between protecting the healing central slip, which requires the middle joint to be held straight, and immobilising the whole finger, which allows the fingertip joint to stiffen in extension and the whole digit to become rigid. The splint is intended to hold one joint while the others keep moving.
Why the deformity gets worse rather than staying still
Boutonnière is a progressive deformity, which is unusual and worth understanding. The central slip attaches to the base of the middle bone and straightens the middle joint. When it fails, that joint drops into flexion, and the two lateral bands, which normally run above the joint's axis, slip below it.
Once they are below the axis, the same tendons that previously helped straighten the middle joint begin to bend it, while pulling the fingertip into hyperextension. The deformity therefore self-reinforces: every attempt to straighten the finger tightens the structures now holding it bent. This is why an injury that looked minor can produce a fixed deformity weeks later, and why the window for simple splinting is early.
The deformity that is not a boutonnière
A finger can adopt the same posture without a central slip injury at all, and the treatments differ entirely. Boutonnière and pseudoboutonnière deformities differ in pathoanatomy, diagnosis and management [2], the pseudo variety arising from a volar plate injury at the middle joint, where the fingertip joint retains normal passive flexion rather than being drawn into hyperextension.
Distinguishing them at the bedside rests on the fingertip. In a true boutonnière the tip is held hyperextended and resists being bent, particularly with the middle joint straightened; in a pseudoboutonnière it flexes freely. Splinting a pseudoboutonnière as though it were the real thing addresses the wrong joint.
It belongs to a family of injuries defined by where the tendon fails
Boutonnière sits alongside mallet finger and sagittal band injury as one of three closed extensor mechanism injuries, categorised by the zone in which the mechanism fails [3]. All three can present as a swollen finger held abnormally within days of an injury, and each requires a different splint position, which is the practical reason a definite diagnosis is worth reaching before committing to weeks of splinting.
References for the advanced reading
- Geoghegan L, Wormald JCR, Adami RZ, Rodrigues JN. Central slip extensor tendon injuries: a systematic review of treatments. J Hand Surg Eur Vol. 2019;44(8):825-32.
- Hanson ZC, Thompson RG, Andrews JR, Lourie GM. Boutonniere versus pseudoboutonniere deformities: pathoanatomy, diagnosis, and treatment. J Hand Surg Am. 2023;48(5):489-97.
- Lin JD, Strauch RJ. Closed soft tissue extensor mechanism injuries (mallet, boutonniere, and sagittal band). J Hand Surg Am. 2014;39(5):1005-11.
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
- Differentiating a true boutonniere deformity from a pseudoboutonniere injury is critical in determining clinical management [1].
- An understanding of the anatomy, clinical presentation, treatment options, and expected outcomes is crucial for optimal treatment of posttraumatic boutonnière and swan neck deformities [2].
- Early treatment of central slip injuries can prevent the deformity [3].
- The natural history of the boutonnière deformity in rheumatoid arthritis is outlined in the literature [5].
- Chronic boutonniere deformity will respond to relative motion flexion splinting if serial casting can place the proximal interphalangeal joint in less than -20° extension [6].
- For chronic boutonniere deformity, the patient must actively use the hand in a relative motion flexion orthosis for 3 months to recover flexion [6].
- 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 [4].
- Extensor tenotomy to correct a boutonnière deformity of long standing markedly lessened disability with restoration of flexion of the distal joint [10].
- Transection of the terminal extensor tendon is a useful procedure for salvage of the boutonniere deformity [13].
- The Y-shaped tendon graft can be a useful procedure for the correction of chronic boutonniere deformity [7].
- In a patient series, the Y-shaped tendon graft provided good or excellent results in 16 of 18 patients for chronic boutonniere deformity [7].
- 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 [9].
- Congenital boutonniere deformity is understood as various embryonic developmental failures [8].
- Central slip reconstruction is a reliable surgical option for the congenital form of boutonniere deformity [8].
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 [19].
- 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 [19].
- In 30% of cases, the EDC has a separate insertion into the base of the proximal phalanx, but extension of the metacarpophalangeal (MP) joint most often occurs through the pull of the sagittal bands [19].
- The deep head of each dorsal interosseous muscle forms a lateral tendon, or lateral band, at the level of the MP joint [25].
- 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 [25].
- 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 at the PIP joint [25].
- The lateral bands are joined by the lateral slips of the extensor tendon to form the conjoined lateral band [25].
- The two conjoined lateral bands 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 [25].
- The volar interossei form the ulnar lateral band of the index finger and the radial lateral band of the ring and little fingers [25].
- 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 [25].
Pathomechanics and Injury
- A boutonniere deformity requires subluxation of the lateral bands volar to the axis of rotation of the PIP joint [15].
- Damage to the central slip alone does not cause a boutonniere deformity [15].
- A boutonniere deformity occurs only when the central slip, triangular ligament, and transverse and oblique fibers of the interosseous hood are all damaged [15].
- Detachment of the central slip from the middle phalanx produces a decrease in extension of the PIP joint [15].
- 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 [15].
- Extension of the PIP joint decreases as structures are progressively damaged [40].
- Injury to the extensor mechanism, specifically the central slip, can lead to snapping or catching at the PIP joint [39].
- In irreducible volar dislocations of the PIP joint caused by interposition of the intact central slip, the extensor mechanism is displaced rather than disrupted [47].
- Long-standing complex pathophysiological changes in boutonniere deformity make full correction impossible, resulting in an inevitable few degrees of PIP joint extension deficit [46].
Classification
- The boutonniere deformity requires subluxation of the lateral bands volar to the axis of rotation of the PIP joint [15].
- Combined injury of the central slip, triangular ligament, and transverse and oblique fibers of the interosseous hood causes a boutonniere deformity [15].
- Anterior dislocation of the proximal interphalangeal joint is associated with ruptures of the central slip of the extensor mechanism [18].
- Anterior dislocation of the proximal interphalangeal joint results in boutonnière deformity unless repaired [18].
- The prevalence of boutonnière deformity without rheumatoid arthritis or trauma is approximately 13% [11].
Clinical Presentation
- A swan-neck or boutonniere deformity occurs in approximately half of patients with rheumatoid arthritis [16].
- 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 [16].
- The prevalence of finger deformities in patients with established rheumatoid arthritis is approximately 36% for boutonniere deformities [16].
- The cause of boutonniere deformity in rheumatoid arthritis is chronic synovitis of the proximal interphalangeal joint [16].
- Boutonniere deformities can be painful and can impair finger and hand function significantly [16].
- A boutonniere deformity requires subluxation of the lateral bands volar to the axis of rotation of the proximal interphalangeal joint [15].
- Detachment of the central slip from the middle phalanx produces a decrease in extension of the proximal interphalangeal joint [15].
- Division of the central slip leads to loss of extension at the proximal interphalangeal joint [15].
Investigations
- A careful physical examination is essential to direct care and future testing if indicated [22].
- 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 [22].
- The extensor mechanism of the finger at the level of the PIP joint consists of both intrinsic and extrinsic contributions [19].
- The extensor tendon that enters the digit is the continuation of the extensor digitorum communis (EDC) and in the index and small fingers the extensor indicis proprius and extensor digiti quinti, respectively [19].
- Thirty percent of the time the EDC has a separate insertion into the base of the proximal phalanx [19].
- Extension of the metacarpophalangeal (MP) joint most of the time occurs through the pull of the sagittal bands [19].
- A finite element model was developed and validated that successfully replicated the behavior of the digit under specific scenarios, including the extension of the DIP joint during Elson's test observed in cadaveric studies [12].
- In a cadaver model, detachment of the central slip from the middle phalanx produced a decrease in extension of the PIP joint [15].
- In a cadaver model, when the transverse and oblique fibers of the interosseous hood were also divided, extension at the PIP joint was further decreased [15].
- In a cadaver model, a boutonniere deformity occurred only when the central slip, triangular ligament, and transverse and oblique fibers of the interosseous hood were all damaged [15].
Non-Operative
- Chronic boutonniere deformity should be treated with serial casting for adequate extension followed by 3 months of relative motion flexion (RMF) orthotic use prior to surgical intervention [4].
- 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 [6].
- The use of relative motion flexion orthoses (RMFO) is effective in increasing active distal interphalangeal joint flexion and improving PIP extension in patients with Burton stage 1 chronic boutonniere deformity [36].
- Improvement in digit range of motion is associated with the initiation of treatment within 6 weeks [21].
- Improvement in digit range of motion is not associated with any particular type or length of conservative treatment [21].
- Conservative treatment for central slip injuries involves immobilization of the proximal interphalangeal joint, distal interphalangeal joint, and metacarpophalangeal joint in full extension for four weeks followed by a Capener spring splint for two further weeks [45].
- In a review of 115 central slip injuries, 24 uncomplicated closed or compound injuries treated conservatively resulted in 17 patients (71%) achieving an outcome of less than a 20° extension deficit at the PIPJ and more than 80% return of PIPJ flexion [45].
- Patients treated within six weeks of injury had better outcomes in conservative management of central slip injuries [45].
Operative
- A simple method of repair is described for the correction of the boutonnière deformity in rheumatoid arthritis [5].
- The Y-shaped tendon graft is a useful procedure for the correction of chronic boutonniere deformity [7].
- The cross-lateral band reconstruction technique using palmaris longus autograft is a treatment option for chronic boutonniere deformity when the lateral bands are deficient or damaged [9].
- The cross-lateral band reconstruction technique using palmaris longus autograft yields satisfactory results in chronic boutonniere deformity [9].
Complications
- The prevalence of finger deformities in patients with established rheumatoid arthritis is approximately 14% for swan-neck deformities [16].
- Swan-neck deformity may be caused by synovitis of the metacarpophalangeal, proximal interphalangeal, or distal interphalangeal joints [16].
- In the later stages of both swan-neck and boutonniere deformities, soft-tissue procedures alone may not result in lasting operative correction [16].
Recovery
- Chronic boutonniere deformity should be treated with serial casting for adequate extension followed by 3 months of relative motion flexion orthotic use prior to surgical intervention [4].
- 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 [6].
- The Y-shaped tendon graft provided good or excellent results in 16 of 18 patients for the correction of chronic boutonniere deformity [7].
- 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 [16].
- The prevalence of finger deformities in patients with established rheumatoid arthritis is approximately 14% for swan-neck deformities and 36% for boutonniere deformities [16].
- Treatment decisions for boutonniere deformity in rheumatoid arthritis are based on the degree of joint deformity, joint motion, passive joint correctability, and the status of the articular surface [20].
Key Evidence
- [L5] Differentiating a true boutonniere deformity from a pseudoboutonniere injury is critical in determining clinical management. [1] (10.1016/j.jhsa.2022.10.019)
- [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. [2] (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. [3] (10.1016/s0749-0712(21)00060-3)
- [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. [4] (10.1016/j.jht.2023.02.005)
- [L4] The natural history of the boutonnière deformity in rheumatoid arthritis is outlined, and a simple method of repair is described. [5] (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. [6] (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. [7] (10.1016/j.jhsa.2021.01.003)
- [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. [8] (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. [9] (10.1016/j.jhsa.2017.04.010)
- [L3] The prevalence of boutonnière deformity without rheumatoid arthritis or trauma is approximately 13%. [11] (10.1177/1753193417704610)
- [L5] The study developed and validated a finite element model that successfully replicated the behavior of the digit under specific scenarios, including the extension of the DIP joint during Elson's test observed in cadaveric studies. [12] (10.1186/s13018-025-06329-3)
- [L4] Transection of the terminal extensor tendon is a useful procedure for salvage of the boutonniere deformity. [13] (10.1016/s0749-0712(21)00065-2)
- [L5] [15] (10.1016/j.jhsa.2017.07.011)
- [L5] [16] (10.5435/00124635-199903000-00002)
- [Paper] [19] (10.1016/j.hcl.2012.05.044)
- [L5] Treatment decisions are based on the degree of joint deformity, joint motion, passive joint correctability, and the status of the articular surface. [20] (10.1016/j.jhsa.2011.05.029)
- [L3] Improvement in digit ROM was associated with initiation of treatment within 6 weeks, but not with any particular type or length of conservative treatment. [21] (10.1016/j.jht.2025.02.013)
- [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. [36] (10.1016/j.jhsa.2022.08.007)
- [Case_report] Hand surgeons should be aware that injury to the extensor mechanism and specifically the central slip can lead to snapping or catching at the PIP joint in the finger. [39] (10.1177/15589447221081876)
- [Paper] Extension of the PIP joint decreases as these structures are progressively damaged. [40] (10.1016/s0363-5023(12)60014-8)
- [L4] [45] (10.1177/1758998318822663)
- [L4] Due to long-standing complex pathophysiological changes, full correction may not be possible, and a few degrees of PIP joint extension deficit is inevitable. [46] (10.1016/j.otsr.2021.102971)
- [L4] The prognosis is far better after irreducible than after reducible volar dislocations because the extensor mechanism is displaced, not disrupted. [47] (10.2106/00004623-197860010-00023)
References
[1] Boutonniere Versus Pseudoboutonniere Deformities: Pathoanatomy, Diagnosis, and Treatment. The Journal of Hand Surgery. 2023. DOI: 10.1016/j.jhsa.2022.10.019
[2] Posttraumatic Boutonnière and Swan Neck Deformities. Journal of the American Academy of Orthopaedic Surgeons. 2015. DOI: 10.5435/jaaos-d-14-00272
[3] BOUTONNIERE DEFORMITY. Hand Clinics. 1995. DOI: 10.1016/s0749-0712(21)00060-3
[4] 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
[5] Correction of the Rheumatoid Boutonnière Deformity. The Journal of Bone & Joint Surgery. 1969. DOI: 10.2106/00004623-196951070-00009
[6] A Paradigm Shift in Managing Acute and Chronic Boutonniere Deformity. Annals of Plastic Surgery. 2020. DOI: 10.1097/sap.0000000000002307
[7] 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
[8] 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
[9] 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
[10] Extensor Tenotomy for Chronic Boutonniere Deformity of the Finger: REPORT OF TWO CASES.. The Journal of Bone and Joint Surgery. American Volume. 1965.
[11] Thumb boutonnière deformity without rheumatoid arthritis or trauma. Journal of Hand Surgery (European Volume). 2017. DOI: 10.1177/1753193417704610
[12] 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
[13] TREATMENT OF THE CHRONIC BOUTONNIERE DEFORMITY BY EXTENSOR TENOTOMY. Hand Clinics. 1995. DOI: 10.1016/s0749-0712(21)00065-2
[15] Biomechanics of the Acute Boutonniere Deformity. The Journal of Hand Surgery. 2018. DOI: 10.1016/j.jhsa.2017.07.011
[16] 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
[18] 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.
[19] Boutonnière and Pulley Rupture in Elite Athletes. Hand Clinics. 2012. DOI: 10.1016/j.hcl.2012.05.044
[20] Treatment of Boutonniere Finger Deformity in Rheumatoid Arthritis. The Journal of Hand Surgery. 2011. DOI: 10.1016/j.jhsa.2011.05.029
[21] Nonoperative treatment of the Boutonniere deformity: Is there a difference in outcomes?. Journal of Hand Therapy. 2025. DOI: 10.1016/j.jht.2025.02.013
[22] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Anatomy, Evaluation, Clinical Examination, and Imaging > Evaluation and Clinical Examination: Current Concepts.
[25] Green S Operative Hand Surgery. Interosseous and Hypothenar Muscles.
[36] 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
[39] Longitudinal Tear of the Central Slip Causing Painful and Unusual Snapping of the Finger: A Case Report. HAND. 2022. DOI: 10.1177/15589447221081876
[40] Biomechanics of the Acute Boutonniere Deformity. The Journal of Hand Surgery. 2012. DOI: 10.1016/s0363-5023(12)60014-8
[45] Therapeutic management of closed central slip injuries: Outcome of a service evaluation. Hand Therapy. 2019. DOI: 10.1177/1758998318822663
[46] RETRACTED: Flexor Digitorum Superficialis tendon transfer for a long-standing boutonniere deformity finger- a retrospective study of 11 cases. Orthopaedics & Traumatology: Surgery & Research. 2021. DOI: 10.1016/j.otsr.2021.102971
[47] Irreducible volar dislocation of the proximal interphalangeal joint of a finger caused by interposition of the intact central slip. The Journal of Bone & Joint Surgery. 1978. DOI: 10.2106/00004623-197860010-00023
