Boutonnière Deformity Info Evidence
Reviewed by Dr Kieran Hirpara, Specialist Orthopaedic Surgeon Last reviewed
What you're feeling
You may notice your finger bending in an unusual way. The middle joint of your finger often bends downward, while the joint at the tip hyperextends or sticks out. This specific shape is called a boutonnière deformity. It can happen after an injury or develop over time. In some cases, it appears without any clear cause or history of rheumatoid arthritis.
Pain is common around the base of the affected finger. You might feel tenderness where the tendons on the back of your hand meet the finger. The discomfort often worsens when you try to straighten your finger against resistance. Simple tasks like typing, opening jars, or buttoning a shirt can become difficult. You may find it hard to grip objects firmly or make a full fist.
If the deformity is linked to rheumatoid arthritis, symptoms may flare up in the morning. Stiffness is often most noticeable after you have been resting. As the day goes on, movement might feel slightly easier, but the joint remains unstable. Without treatment, the position of your finger can change permanently. The skin over the bent joint may become tight or irritated.
It is important to distinguish this true deformity from a similar injury called pseudoboutonniere. The two conditions look alike but require different care. Understanding your specific symptoms helps your surgeon choose the right path. Early recognition allows for better management of pain and function.
In some cases, the condition progresses slowly. The joint at the tip of your finger may begin to bend inward as well. This secondary change can further limit your hand’s range of motion. You might notice that your fingers do not align neatly when you rest them on a table. These changes can affect your ability to perform daily activities with ease.
If you experience these signs, please seek evaluation. Accurate diagnosis is the first step toward relief. Your surgeon will examine your hand to determine the exact nature of the issue. This clarity ensures that the treatment plan matches your specific needs.
What's actually happening
Your finger has a system of tendons that act like ropes to straighten and bend it. In a Boutonnière deformity, one of these central ropes—the central slip—gets injured or weakens. This rope sits on top of your middle finger joint. When it fails, the balance of forces in your finger changes completely.
Think of your finger joint like a door hinge with two strings attached. One string pulls the finger straight, and another pulls it bent. Normally, they work together smoothly. When the central slip is damaged, it can no longer hold the middle joint straight. The other tendons then pull out of place. This causes the middle joint to bend inward while the tip joint overextends. The result is a visible crooked shape.
The most important factor in this problem is how quickly the tendons and related structures change. In the early stages, these tissues are still flexible. If you catch it early, we can often guide them back to their normal position. We use splints to hold the middle joint straight, giving the tendon a chance to heal. This approach can improve your range of motion by one to two grades. However, even with dedicated conservative management, the deformity can persist.
If the injury is older or more severe, the tendons may have shortened or scarred. The joint itself might become unstable. In these cases, simple splinting is not enough. We may need to reconstruct the central slip using a small piece of tendon from nearby. This acts like a new rope to restore balance. The main goals are to keep your joint centered, restore stability, and help you move your finger again.
It is critical to distinguish a true Boutonnière deformity from similar injuries. A wrong diagnosis leads to the wrong treatment. If left untreated, the deformity can become fixed. In some cases, such as those linked to rheumatoid arthritis, long-term results from soft tissue reconstruction can be unreliable. We assess your specific situation to determine if non-surgical methods will work or if surgical intervention is needed to prevent permanent loss of function.
What we can do about it
How Dr Kieran Hirpara, an upper-limb surgeon at Mater Private Hospital Rockhampton, approaches this in our clinic reflects a careful step-by-step plan. We start by confirming exactly what you have. It is critical to tell the difference between a true boutonniere deformity and a similar injury called pseudoboutonniere. This distinction changes how we treat you. We begin with non-operative care for long-standing or degenerative issues. For acute structural problems, we may recommend surgery right away.
You can start with self-management and physiotherapy. We often use serial casting to help straighten your finger, followed by three months of wearing a special splint called a relative motion flexion orthosis. This device helps improve movement in your finger joints. Physiotherapy aims to restore your range of motion. You might see one to two grades of improvement with this approach. However, the deformity can persist even after dedicated conservative management. We give this time to work, but we monitor your progress closely.
If pain or stiffness remains, we discuss medical management. This may include pain medication or anti-inflammatory drugs to reduce swelling. In some cases, we consider injections such as cortisone to calm inflammation. These treatments help manage symptoms but do not fix the underlying tendon imbalance. We review how long the effect lasts for you and adjust the plan if needed.
Surgery is considered when conservative care has not given enough improvement. We look at your specific anatomy and the stage of your deformity to choose the right procedure. For chronic cases, we might use a Y-shaped tendon graft to correct the alignment. This technique provided good or excellent results in 16 of 18 patients in reported studies. For rheumatoid arthritis, long-term soft tissue reconstruction can be unreliable, so we may discuss a salvage procedure if the deformity returns. We ensure you understand the timing and expected outcomes before proceeding.
What to expect
Your finger may feel stiff or bent in a way that feels permanent. This condition often develops slowly. Without treatment, the deformity can persist even if you try dedicated conservative management. You might see one to two grades of range of motion improvement with non-surgical care. However, the shape of your finger may not return to normal.
If you have rheumatoid arthritis, long-term results following soft tissue reconstruction are unreliable. Recurrent or persistent deformity is best treated with a salvage procedure. In cases without rheumatoid arthritis or trauma, the prevalence of this deformity is approximately 13%. Differentiating a true boutonniere deformity from a pseudoboutonniere injury is critical in determining clinical management.
For chronic cases, serial casting for adequate extension followed by 3 months of relative motion flexion orthotic use yields similar results. This approach should be attempted prior to surgical intervention. If surgery is needed, the Y-shaped tendon graft is a useful procedure. It provides good or excellent results in 16 of 18 patients in a reported series. A successful operative result depends on complete preoperative examination, correct staging of the deformity, and proper timing of treatment.
Recovery is a gradual process. You will need to manage your expectations regarding the final shape and function of your finger. While many patients achieve significant improvement, some may continue to experience limitations. Your surgeon will guide you through the appropriate steps based on the specific stage of your condition.
When to see someone
See your GP if you notice a persistent bend in the middle joint of your finger that does not straighten. Ask for a specialist review if you have persistent pain that does not improve with rest, or if your hand feels weak and unstable. Seek care if your finger locks or gives way during use. Symptoms that interfere with sleep or daily work also warrant attention. Sudden worsening of the deformity requires prompt evaluation. Accurate diagnosis is critical because true boutonniere deformity differs from similar injuries. This distinction guides your treatment plan. Early assessment helps prevent long-term stiffness and ensures the correct management path for your specific injury.
Evidence & references
Overview
- Differentiating a true boutonniere deformity from a pseudoboutonniere injury is critical in determining clinical management [2].
- An understanding of the anatomy, clinical presentation, treatment options, and expected outcomes is crucial for optimal treatment of posttraumatic boutonniere and swan neck deformities [4].
- The natural history of the boutonnière deformity in rheumatoid arthritis is outlined, and a simple method of repair is described [3].
- The prevalence of boutonnière deformity without rheumatoid arthritis or trauma is approximately 13% [5].
- One to two grades of ROM improvement can be achieved with nonoperative treatment, although deformity can persist even after dedicated conservative management [8].
- 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 [1].
- Long-term results following soft tissue reconstruction for boutonniere deformity in rheumatoid arthritis are unreliable, and recurrent or persistent deformity is best treated with a salvage procedure [9].
- A successful operative result for swan-neck and boutonniere deformities in the rheumatoid hand depends on complete preoperative examination, correct staging of the deformity, and proper timing of treatment [10].
- The Y-shaped tendon graft can be a useful procedure for the correction of chronic boutonniere deformity, providing good or excellent results in 16 of 18 patients in one series [6].
- Detachment of up to two-thirds of the phalangeal length was effective in reducing extensor lag of the DIP joint and did not cause any boutonniere deformity in a cadaveric model of fractional Fowler tenotomy for chronic mallet finger [7].
Anatomy & Pathophysiology
- Boutonnière deformity can persist even after dedicated conservative management [8].
- One to two grades of range of motion improvement can be achieved with nonoperative treatment of Boutonnière deformity [8].
- Accurate diagnosis and treatment of finger metacarpophalangeal joint injuries begins with an understanding of all potential diagnoses [15].
- Hand surgery and hand therapy practice interventions, including use of relative motion flexion orthoses for management of non-surgical and surgical extensor mechanism injuries, may benefit from an in-depth look at extensor mechanism zone III and IV anatomy and biomechanics [19].
- The most important factor in the development of finger deformities is the changes occurring in the tendons and related structures, especially in early stages [21].
- Reconstruction of the extensor central slip using a distally based flexor digitorum superficialis slip provides a robust repair that anatomically mimics the extensor central slip while maintaining the function of the donor FDS tendon [24].
- The main goals of any treatment of a proximal interphalangeal joint complication are maintaining concentric reduction of the joint, restoring joint stability, and facilitating early range-of-motion exercises [33].
Classification
- Differentiating a true boutonniere deformity from a pseudoboutonniere injury is critical in determining clinical management [2].
- The natural history of the boutonnière deformity in rheumatoid arthritis is outlined [3].
- The prevalence of boutonnière deformity without rheumatoid arthritis or trauma is approximately 13% [5].
- A modified Terrono classification for Type 1 thumb deformity in rheumatoid arthritis could detect advanced deformity earlier and was more strongly correlated with hand function [17].
Clinical Presentation
- Differentiating a true boutonniere deformity from a pseudoboutonniere injury is critical in determining clinical management [2].
- An understanding of the clinical presentation is crucial for optimal treatment of posttraumatic boutonnière and swan neck deformities [4].
- Accurate diagnosis of finger metacarpophalangeal joint injuries begins with an understanding of all potential diagnoses [15].
- The natural history of the boutonnière deformity in rheumatoid arthritis is outlined in historical literature [3].
- The prevalence of boutonnière deformity without rheumatoid arthritis or trauma is approximately 13% [5].
- The swan neck deformity can progress significantly with time due to increasing distal interphalangeal joint flexion contracture [14].
Investigations
- Differentiating a true boutonniere deformity from a pseudoboutonniere injury is critical in determining clinical management [2].
- 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].
- Accurate diagnosis and treatment of finger metacarpophalangeal joint injuries begins with an understanding of all potential diagnoses [15].
- It is necessary to determine the true etiology before surgical intervention [12].
- A successful operative result depends on complete preoperative examination, correct staging of the deformity, and proper timing of treatment [10].
- Cortical breaks were commonly visualized in MCP and PIP joints with HR-pQCT and microCT [37].
Treatment
- 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 [1].
- Differentiating a true boutonniere deformity from a pseudoboutonniere injury is critical in determining clinical management [2].
- A simple method of repair is described for the boutonnière deformity in rheumatoid arthritis [3].
- Understanding the anatomy, clinical presentation, treatment options, and expected outcomes is crucial for optimal treatment of posttraumatic boutonnière and swan neck deformities [4].
- The prevalence of boutonnière deformity without rheumatoid arthritis or trauma is approximately 13% [5].
- The Y-shaped tendon graft is a useful procedure for the correction of chronic boutonniere deformity, providing good or excellent results in 16 of 18 patients in a reported series [6].
- Detachment of up to two-thirds of the phalangeal length is effective in reducing extensor lag of the DIP joint and does not cause any boutonniere deformity in a cadaveric model [7].
- One to two grades of ROM improvement can be achieved with nonoperative treatment, although deformity can persist even after dedicated conservative management [8].
- Long-term results following soft tissue reconstruction for boutonniere deformity in rheumatoid arthritis are unreliable, and recurrent or persistent deformity is best treated with a salvage procedure [9].
- A successful operative result for swan-neck and boutonniere deformities in the rheumatoid hand depends on complete preoperative examination, correct staging of the deformity, and proper timing of treatment [10].
- Metacarpophalangeal joint arthroplasty improves function and deformity and achieves nearly uniform patient satisfaction in rheumatoid arthritis [11].
- One technique does not treat all finger deformities uniformly, highlighting the need to determine the true etiology before surgical intervention [12].
- 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 [13].
Complications
- Differentiating a true boutonniere deformity from a pseudoboutonniere injury is critical in determining clinical management [2].
- The prevalence of boutonniere deformity without rheumatoid arthritis or trauma is approximately 13% [5].
- Detachment of up to two-thirds of the phalangeal length was effective in reducing extensor lag of the DIP joint and did not cause any boutonniere deformity in a cadaveric model [7].
- Long-term results following soft tissue reconstruction for boutonniere finger deformity in rheumatoid arthritis are unreliable [9].
- Recurrent or persistent deformity is best treated with a salvage procedure [9].
- A successful operative result depends on complete preoperative examination, correct staging of the deformity, and proper timing of treatment [10].
- One technique does not treat all deformities uniformly, highlighting the need to determine the true etiology before surgical intervention [12].
- Swan neck deformity can progress significantly with time due to increasing DIPJ flexion contracture [14].
Recovery
- Serial casting for adequate extension followed by 3 months of relative motion flexion (RMF) orthotic use yields similar results for chronic boutonniere deformity and should be attempted prior to surgical intervention [1].
- One to two grades of range of motion (ROM) improvement can be achieved with nonoperative treatment, although deformity can persist even after dedicated conservative management [8].
- The Y-shaped tendon graft is a useful procedure for the correction of chronic boutonniere deformity, providing good or excellent results in 16 of 18 patients in a reported series [6].
- The use of relative motion flexion orthoses (RMFO) is effective in increasing active distal interphalangeal joint flexion and improving proximal interphalangeal (PIP) extension in patients with Burton stage 1 chronic boutonniere deformity [13].
- Long-term results following soft tissue reconstruction for boutonniere deformity in rheumatoid arthritis are unreliable, and recurrent or persistent deformity is best treated with a salvage procedure [9].
- A successful operative result for boutonniere deformity depends on complete preoperative examination, correct staging of the deformity, and proper timing of treatment [10].
Key Evidence
- [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. [1] (10.1016/j.jht.2023.02.005)
- [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] The natural history of the boutonnière deformity in rheumatoid arthritis is outlined, and a simple method of repair is described. [3] (10.2106/00004623-196951070-00009)
- [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)
- [L3] The prevalence of boutonnière deformity without rheumatoid arthritis or trauma is approximately 13%. [5] (10.1177/1753193417704610)
- [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. [6] (10.1016/j.jhsa.2021.01.003)
- [L5] Detachment of up to two-thirds of the phalangeal length was effective in reducing extensor lag of the DIP joint and did not cause any boutonniere deformity in this cadaveric model. [7] (10.1016/j.jhsa.2012.07.039)
- [L3] One to two grades of ROM improvement can be achieved, although deformity can persist even after dedicated conservative management. [8] (10.1016/j.jht.2025.02.013)
- [L5] Long-term results following soft tissue reconstruction are unreliable, and recurrent or persistent deformity is best treated with a salvage procedure. [9] (10.1016/j.jhsa.2011.05.029)
- [L5] A successful operative result depends on complete preoperative examination, correct staging of the deformity, and proper timing of treatment. [10] (10.5435/00124635-199903000-00002)
- [L5] Follow-up studies show that this surgery improves function and deformity and achieves nearly uniform patient satisfaction. [11] (10.5435/00124635-200305000-00005)
- [L5] It emphasizes that one technique does not treat all deformities uniformly and highlights the need to determine the true etiology before surgical intervention. [12] (10.1016/j.jhsa.2022.07.008)
- [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. [13] (10.1016/j.jhsa.2022.08.007)
- [L5] The swan neck deformity in this individual progressed significantly with time because of increasing DIPJ flexion contracture. [14] (10.1016/j.jht.2009.11.005)
- [L5] Accurate diagnosis and treatment of finger metacarpophalangeal joint injuries in athletes begins with an understanding of all potential diagnoses, allowing for safe and early return to play. [15] (10.5435/jaaos-d-21-01031)
- [L3] The modified classification could detect advanced deformity earlier and was more strongly correlated with hand function. [17] (10.1177/1753193419886719)
- [L5] Hand surgery and hand therapy practice interventions, including use of RMF orthoses for management of non-surgical and surgical EM injuries may benefit from an in-depth look at the EM zone III and IV anatomy and biomechanics. [19] (10.1016/j.jht.2023.01.002)
- [L4] The most important factor in the development of finger deformities is the changes occurring in the tendons and related structures, especially in early stages. [21] (10.2106/00004623-195739030-00006)
- [L4] The modified technique provides a robust repair that anatomically mimics the extensor central slip yet maintains the function of the donor FDS tendon. [24] (10.1016/j.jhsa.2009.01.025)
- [L5] The main goals of any treatment of a PIP joint complication are maintaining concentric reduction of the joint, restoring joint stability, and facilitating early range-of-motion exercises. [33] (10.1016/j.hcl.2017.12.014)
- [L4] Cortical breaks were commonly visualized in MCP and PIP joints with HR-pQCT and microCT. [37] (10.1186/s12891-016-1148-y)
References
[1] 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 [2] Boutonniere Versus Pseudoboutonniere Deformities: Pathoanatomy, Diagnosis, and Treatment. The Journal of Hand Surgery. 2023. DOI: 10.1016/j.jhsa.2022.10.019 [3] Correction of the Rheumatoid Boutonnière Deformity. The Journal of Bone & Joint Surgery. 1969. DOI: 10.2106/00004623-196951070-00009 [4] Posttraumatic Boutonnière and Swan Neck Deformities. Journal of the American Academy of Orthopaedic Surgeons. 2015. DOI: 10.5435/jaaos-d-14-00272 [5] Thumb boutonnière deformity without rheumatoid arthritis or trauma. Journal of Hand Surgery (European Volume). 2017. DOI: 10.1177/1753193417704610 [6] 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 [7] Fractional Fowler Tenotomy for Chronic Mallet Finger: A Cadaveric Biomechanical Study. The Journal of Hand Surgery. 2012. DOI: 10.1016/j.jhsa.2012.07.039 [8] 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 [9] Treatment of Boutonniere Finger Deformity in Rheumatoid Arthritis. The Journal of Hand Surgery. 2011. DOI: 10.1016/j.jhsa.2011.05.029 [10] 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 [11] Metacarpophalangeal Joint Arthroplasty in Rheumatoid Arthritis. Journal of the American Academy of Orthopaedic Surgeons. 2003. DOI: 10.5435/00124635-200305000-00005 [12] Clarification of Extensor Tenotomy for Finger Deformities. The Journal of Hand Surgery. 2022. DOI: 10.1016/j.jhsa.2022.07.008 [13] 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 [14] Swan Neck Deformity after Distal Interphalangeal Joint Flexion Contractures: A Biomechanical Analysis. Journal of Hand Therapy. 2010. DOI: 10.1016/j.jht.2009.11.005 [15] Finger Metacarpophalangeal Joint Injuries in Athletes: Evaluation, Diagnosis, Treatment, and Return to Play. Journal of the American Academy of Orthopaedic Surgeons. 2023. DOI: 10.5435/jaaos-d-21-01031 [17] A modified Terrono classification for Type 1 thumb deformity in rheumatoid arthritis: a cross-sectional analysis. Journal of Hand Surgery (European Volume). 2019. DOI: 10.1177/1753193419886719 [19] An in-depth look at zone III and IV anatomy of the finger extensor mechanism and some clinical implications for use of the relative motion flexion orthosis. Journal of Hand Therapy. 2023. DOI: 10.1016/j.jht.2023.01.002 [21] Finger Deformities Caused by Rheumatoid Arthritis. The Journal of Bone & Joint Surgery. 1957. DOI: 10.2106/00004623-195739030-00006 [24] Reconstruction of the Extensor Central Slip Using a Distally Based Flexor Digitorum Superficialis Slip. The Journal of Hand Surgery. 2009. DOI: 10.1016/j.jhsa.2009.01.025 [33] Complications of Proximal Interphalangeal Joint Injuries. Hand Clinics. 2018. DOI: 10.1016/j.hcl.2017.12.014 [37] Visual detection of cortical breaks in hand joints: reliability and validity of high-resolution peripheral quantitative CT compared to microCT. BMC Musculoskeletal Disorders. 2016. DOI: 10.1186/s12891-016-1148-y
