Boutonnière Deformity occurs when the central slip of the extensor tendon—the tendon responsible for straightening the middle joint of the finger—is injured or weakened. As a result, the middle joint bends toward the palm while the fingertip joint bends backward into hyperextension.

The term "Boutonnière" is French for "buttonhole," describing the appearance of the tendon slipping through surrounding structures after injury.

This condition most commonly affects:

• The middle finger
• The ring finger
• Occasionally other fingers

Boutonnière Deformity can develop suddenly following trauma or gradually due to inflammatory conditions such as rheumatoid arthritis.

Early diagnosis and treatment are important to prevent permanent joint stiffness and deformity.

At Magnum Physiotherapy, our rehabilitation programs focus on restoring tendon function, improving finger mobility, strengthening hand muscles, and maximizing overall hand performance.

Anatomy Involved

Extensor Tendon Mechanism

The extensor tendon runs along the back of the finger and allows finger straightening.

Central Slip

The central slip attaches to the middle phalanx and straightens the proximal interphalangeal (PIP) joint.

When damaged, normal finger extension becomes compromised.

Proximal Interphalangeal (PIP) Joint

The middle joint of the finger.

In Boutonnière Deformity, this joint becomes flexed (bent).

Distal Interphalangeal (DIP) Joint

The joint closest to the fingertip.

In Boutonnière Deformity, this joint becomes hyperextended.

Causes & Risk Factors

Traumatic Causes

• Direct blow to the finger
• Finger lacerations
• Sports injuries
• Crushing injuries
• Finger dislocations

Non-Traumatic Causes

Rheumatoid Arthritis

A common cause of chronic Boutonnière Deformity due to tendon weakening.

Other Inflammatory Conditions

• Psoriatic Arthritis
• Lupus
• Chronic synovitis

Risk Factors

• Contact sports participation
• Previous finger injuries
• Rheumatoid arthritis
• Occupational hand trauma

Common Symptoms

• Bent middle finger joint
• Hyperextended fingertip
• Difficulty straightening the finger
• Finger pain
• Swelling
• Stiffness
• Weak grip strength
• Reduced hand dexterity
• Functional difficulties during daily activities

Symptoms may develop immediately after injury or gradually over time.

Conditions Associated with Boutonnière Deformity

• Rheumatoid Arthritis
• Finger Dislocations
• Extensor Tendon Injuries
• Finger Fractures
• Hand Trauma
• Chronic Joint Inflammation

Diagnosis

Early diagnosis improves treatment outcomes.

Clinical Examination

A healthcare provider may assess:

• Finger alignment
• Joint mobility
• Tendon function
• Finger extension strength

Special Tests

Elson Test

A commonly used clinical test to evaluate central slip injuries.

Imaging Studies

X-rays

Used to identify:

• Fractures
• Joint damage
• Alignment abnormalities

Ultrasound or MRI

May be used when tendon injuries require further evaluation.

At Magnum Physiotherapy, we assess:

• Finger mobility
• Hand strength
• Functional limitations
• Dexterity
• Activity participation

Treatment at Magnum Physiotherapy

Treatment depends on the severity and duration of the condition.

Conservative Management

Many cases respond well to non-surgical treatment when addressed early.

Splinting

The PIP joint is maintained in extension to allow tendon healing.

Splinting may be required for:

• Several weeks
• Continuous wear depending on injury severity

Physiotherapy Rehabilitation

Following the immobilization phase, rehabilitation focuses on restoring motion and function.

Range of Motion Exercises

Designed to:

• Improve joint mobility
• Prevent stiffness
• Restore normal movement patterns

Tendon Gliding Exercises

Help maintain tendon mobility and function.

Strengthening Exercises

Focus on:

• Finger extensors
• Grip strength
• Hand endurance

Functional Hand Training

Includes:

• Fine motor skill activities
• Dexterity exercises
• Daily activity retraining

Advanced Physiotherapy Treatments

Depending on patient needs:

• Soft Tissue Mobilization
• Joint Mobilization
• Scar Tissue Management
• Therapeutic Exercise Programs
• Functional Rehabilitation

Surgical Management

Surgery may be recommended when:

• Conservative treatment fails
• The deformity becomes fixed
• Significant tendon damage is present
• Chronic deformity limits function

Surgical Procedures May Include

• Tendon repair
• Tendon reconstruction
• Joint realignment procedures

Post-surgical physiotherapy is essential for restoring function and preventing stiffness.

Benefits of Physiotherapy for Boutonnière Deformity

• Improves finger mobility
• Restores tendon function
• Enhances grip strength
• Improves dexterity
• Reduces stiffness
• Supports tendon healing
• Improves hand coordination
• Restores daily function
• Supports return to work and sports
• Enhances quality of life

Recovery & Prognosis

Recovery depends on:

• Severity of the injury
• Duration before treatment
• Underlying medical conditions
• Compliance with splinting and rehabilitation

Typical Recovery Timeline

Acute Cases

• Several weeks to a few months

Chronic Cases

• May require longer rehabilitation
• Some residual stiffness may remain

Early treatment generally produces the best outcomes.

Potential Complications

Without proper treatment, complications may include:

• Permanent finger deformity
• Joint stiffness
• Reduced hand function
• Chronic pain
• Grip weakness
• Functional limitations

Prompt treatment significantly reduces these risks.

Prevention Tips

• Use proper hand protection during sports
• Treat finger injuries early
• Maintain joint health in inflammatory arthritis
• Follow rehabilitation recommendations after hand injuries

When Should You Seek Medical Attention?

Consult a healthcare professional if you experience:

• Difficulty straightening a finger
• Persistent finger swelling
• Finger deformity after injury
• Loss of hand function
• Progressive finger stiffness

Early diagnosis and treatment can help prevent long-term complications.

Why Choose Magnum Physiotherapy?

At Magnum Physiotherapy, we specialize in hand rehabilitation and orthopedic physiotherapy. Our personalized Boutonnière Deformity treatment programs combine evidence-based rehabilitation, splinting guidance, mobility restoration, strengthening exercises, and functional retraining to help patients regain optimal hand function and return to daily activities with confidence