Mallet Finger (Adult)

1. Clinical Overview

Mallet finger represents a disruption of the terminal extensor mechanism at the distal interphalangeal (DIP) joint, resulting in loss of active DIP extension. The injury occurs when sudden forceful flexion is applied to an actively extended DIP joint, typically during ball sports when a ball strikes the fingertip. This mechanism causes either rupture of the terminal extensor tendon (tendinous mallet) or avulsion fracture of the dorsal base of the distal phalanx (bony mallet). The characteristic clinical presentation is a drooped fingertip with inability to actively extend the DIP joint, though passive extension remains intact. [1,2]

Mallet finger is one of the most common closed tendon injuries of the hand, with an estimated incidence of 9.4 per 100,000 population per year. [3] Despite its apparent simplicity, the condition requires meticulous management with prolonged continuous splinting to achieve tendon healing. Non-operative management with continuous DIP extension splinting for 6-8 weeks remains the gold standard treatment for the vast majority of cases. [4,5] Surgical intervention is reserved for specific indications including large bony fragments involving > 30% of the articular surface, volar subluxation of the distal phalanx, open injuries, or failed conservative management. [6,7]

The prognosis with appropriate treatment is generally favourable, though residual extensor lag of 5-15 degrees is common and typically functionally acceptable. [8] Patient compliance with continuous splinting is the critical determinant of outcome – any flexion of the DIP joint during the immobilization period disrupts healing and necessitates restarting the splinting protocol. [9] Chronic untreated mallet finger can lead to secondary swan-neck deformity due to extensor mechanism imbalance, requiring complex surgical reconstruction. [10]

Clinical Pearls

"Can't Straighten the Tip": The pathognomonic finding is flexed DIP joint with inability to actively extend, but full passive extension is possible – distinguishing this from arthrodesis or joint destruction.

"Splint Continuously or Start Again": The DIP must be held in extension (0-10° hyperextension) for 6-8 weeks continuously. ANY flexion episode during this period resets the healing clock to day zero.

"30% Rule for Surgery": Bony fragments involving > 30% of the articular surface of the dorsal distal phalanx base often cause volar subluxation and joint instability, requiring surgical fixation rather than splinting.

"Don't Hyperextend the PIP": The splint should immobilize only the DIP joint while allowing full PIP flexion and extension. Immobilizing the PIP joint predisposes to swan-neck deformity and joint stiffness.

"Ball Sports, Bedsheets, and Baseball": The classic mechanisms are ball striking the fingertip during sports (baseball, basketball, cricket, volleyball) or low-energy domestic injuries such as tucking in bedsheets in elderly patients.

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2. Epidemiology

Incidence and Demographics

Mallet finger is the most common closed tendon injury in the hand, with an incidence of approximately 9.4 per 100,000 population per year. [3] The true incidence is likely higher as many cases are managed in primary care without specialist referral, and minor injuries may go unreported.

Risk Factors

Temporal and Seasonal Patterns

• Peak incidence during spring and summer months (April-September in Northern Hemisphere) correlating with outdoor ball sports seasons [11]
• Weekend peaks reflecting recreational sports participation
• Elderly cohort shows no seasonal variation (domestic mechanisms)

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3. Anatomy and Pathophysiology

Extensor Mechanism at the DIP Joint

The terminal extensor mechanism is formed by the confluence of the lateral bands (derived from the intrinsic muscles and central slip) which insert onto the dorsal base of the distal phalanx. This insertion, known as the terminal extensor tendon, is the sole active extensor of the DIP joint.

Exam Detail: Detailed Anatomy:

• The terminal extensor tendon inserts onto approximately the dorsal 40% of the distal phalanx base articular surface [14]
• The insertion point is approximately 1-2mm distal to the articular margin
• The tendon is relatively thin and flat (2-3mm wide, 1mm thick), making it vulnerable to rupture with minimal trauma
• Blood supply is via peritendinous vessels from the dorsal digital arteries – the zone of insertion is relatively hypovascular
• The tendon relies on vincula system for nutrition during healing

Biomechanics:

• The DIP joint normally extends to 0° (neutral) or up to 10° hyperextension
• The moment arm of the terminal extensor is small (~3mm), requiring minimal force to extend but also making it susceptible to rupture
• Sudden passive flexion force while actively extending creates shear forces exceeding tendon tensile strength (estimated 20-40N rupture threshold) [15]

Pathophysiology of Injury

Mechanism of Injury

The injury occurs through sudden forced flexion of an actively extended DIP joint. This creates:

1. Eccentric contraction of the terminal extensor (muscle attempting to extend while joint is being flexed)
2. Tensile failure at the weakest point – typically the tendon substance itself or the bone-tendon junction
3. If bone quality is compromised (elderly, osteoporosis) or insertion point is vulnerable, an avulsion fracture occurs instead of tendon rupture

Types of Mallet Finger Pathology

Exam Detail: Histopathology of Tendon Rupture:

• Acute rupture: Disruption of collagen fibrils, haemorrhage, inflammatory infiltrate
• Healing phase (weeks 1-6): Fibroblast proliferation, collagen deposition, gradual tensile strength recovery
• Remodelling (weeks 6-12): Collagen realignment along stress lines, scar maturation
• The healed tendon typically shows 10-20% elongation compared to contralateral side, accounting for residual extension lag [16]

Why 6-8 Weeks Splinting?

• Collagen tensile strength reaches ~50% normal at 6 weeks [16]
• Full strength (80% normal) not achieved until 12 weeks
• However, 6 weeks continuous immobilization is sufficient for functional healing in most cases [4,5]
• Bony mallet may require 8 weeks as fracture union adds extra time requirement

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4. Classification

Doyle Classification (Most Widely Used)

Exam Detail: Key Classification Points for Exams:

• Types I-III are based on soft tissue injury pattern (closed vs open)
• Type IV is based on fracture size and joint stability
• The 30% threshold is critical – fragments > 30% often cause joint instability requiring surgery [6,7]
• Volar subluxation indicates disruption of the volar plate in addition to dorsal extensor, making the joint unstable [17]

How to Measure 30% on X-Ray: On lateral radiograph:

• Measure the total dorsal-volar diameter of the distal phalanx articular surface
• Measure the fragment size (maximum dimension)
• Calculate percentage: (Fragment size / Total articular surface) × 100
• If > 30%, consider surgery

Alternative: Wehbe and Schneider Classification

Less commonly used but mentioned in literature:

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5. Clinical Presentation

History

Mechanism of Injury

Presenting Symptoms

Cardinal Symptom: Inability to straighten the fingertip

Time to Presentation:

• Acute (less than 48 hours): 60-70% of cases
• Subacute (2-14 days): 20-25%
• Delayed (> 2 weeks): 10-15% – often after failed self-treatment or initially dismissed as "sprain"

Examination Findings

Inspection

Palpation

Active Movement Assessment

The Pathognomonic Test:

Clinical Pearl: Active DIP Extension Test:

• Ask patient to fully extend all fingers with hand flat on table
• Observe affected DIP joint
• Positive test: DIP remains flexed while patient attempts extension (active extensor lag)
• Quantify lag: Measure angle of flexion deformity (typically 30-50°)

This distinguishes mallet finger (terminal extensor disruption) from:

• FDP avulsion (cannot flex DIP)
• DIP arthrodesis (cannot move DIP passively)
• Central slip injury (affects PIP, not DIP)

Passive Movement Assessment

Key Point: The hallmark of mallet finger is full passive extension with loss of active extension – this confirms extensor mechanism disruption rather than joint pathology.

Special Populations

Exam Detail: Elderly Patients:

• Often sustain injury through low-energy domestic mechanisms (bedsheets, clothing)
• May have degenerative tendon changes predisposing to rupture
• Compliance with prolonged splinting may be challenging
• Higher rate of skin complications from splinting (maceration, pressure sores)
• Consider bony mallet more likely due to osteoporotic bone quality [13]

Athletes:

• Typically young, high demand on fingers
• May present late due to denial or minimization of injury
• Keen to return to sport early – need clear guidance on splinting duration
• Consider early hand therapy referral for guided rehabilitation

Diabetic Patients:

• Risk of skin breakdown under splint
• May have peripheral neuropathy masking discomfort
• Require more frequent splint review and skin checks

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6. Differential Diagnosis

Always consider:

1. Jersey Finger (FDP Avulsion) – Must Not Miss

Key Features:

• Opposite deformity: DIP held in EXTENSION, cannot actively FLEX
• Mechanism: Forceful extension while gripping (jersey pulled from grasp)
• Palpable/visible retracted tendon lump in palm
• Requires urgent surgery (unlike mallet which is usually conservative)

2. Central Slip Injury – Often Confused

Key Features:

• Affects PIP joint, NOT DIP
• Mechanism: Forced flexion of PIP or direct blow
• Leads to boutonniere deformity: PIP flexion, DIP hyperextension
• Elson's test positive (increased DIP extension force with PIP flexed to 90°)

3. DIP Joint Dislocation

Key Features:

• Obvious deformity with displacement
• Unable to passively extend (unlike mallet where passive extension is full)
• X-ray shows joint incongruity
• Requires reduction

4. DIP Arthrodesis (Surgical or Post-Traumatic)

Key Features:

• History of previous surgery or severe trauma
• No active OR passive movement at DIP
• X-ray shows fusion or severe arthritis

5. Mucous Cyst of DIP

Key Features:

• Dorsal cystic swelling over DIP
• May cause extension lag due to mass effect or tendon attenuation
• Chronic gradual onset, not acute trauma
• Usually painless

6. Trigger Finger (DIP Locking)

Key Features:

• Locking or clicking with movement
• Intermittent symptoms, not constant extension loss
• Tenderness over A1 pulley (proximal), not DIP

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7. Investigations

Imaging

Radiographs (ESSENTIAL)

Views Required:

• Lateral view of affected finger (most important – shows fracture fragment size, subluxation)
• PA view (documents baseline, identifies other fractures)
• Oblique view (optional, may help visualize small fragments)

Exam Detail: Radiographic Interpretation Checklist:

1. Identify fracture fragment:

   • Measure size as percentage of articular surface
   • less than 30% articular surface = splinting

   • 30% articular surface = consider surgery

2. Assess joint alignment:

   • Volar subluxation: Distal phalanx displaced volarly/palmarly relative to middle phalanx
   • Indicates unstable injury requiring surgical fixation [17]
   • Measure on lateral view: Draw line along volar cortex of middle phalanx – should align with distal phalanx

3. Check for other injuries:

   • Shaft fractures of distal phalanx
   • Nail bed injury (look for displaced nail, soft tissue swelling)
   • PIP joint involvement

4. Document articular congruity:

   • Step in articular surface suggests large fragment displacement

   • 2mm articular step = poor outcome with conservative management [18]

Advanced Imaging (Rarely Required)

Laboratory Tests

Not routinely required unless:

• Open injury (baseline inflammatory markers if infection concern)
• Systemic inflammatory arthropathy suspected (rheumatoid arthritis, psoriatic arthritis)
• Metabolic bone disease workup in elderly with multiple fragility fractures

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8. Management

Overview of Treatment Strategy

Treatment Algorithm:

MALLET FINGER SUSPECTED
↓
CLINICAL DIAGNOSIS: Active extension lag, full passive extension
↓
X-RAY (Lateral + PA views)
↓
┌─────────────────────────────────────┬────────────────────────────────────┐
│ CLOSED, less than 30% FRACTURE               │ > 30% FRACTURE or SUBLUXATION       │
│ (Doyle I, IVA, IVB without sublux)  │ (Doyle IVB large, IVC)             │
│ = 85-90% of cases                   │ = 10-15% of cases                  │
└─────────────────────────────────────┴────────────────────────────────────┘
         ↓                                           ↓
  NON-OPERATIVE MANAGEMENT                    SURGICAL REFERRAL
  - Continuous DIP extension splinting        - Hand surgery assessment
  - 6-8 weeks full-time                       - ORIF vs extension block
  - 2-4 weeks night-time weaning              - Consider if failed conservative
         ↓                                           ↓
OUTCOMES:                                   SURGICAL FIXATION
  - 70-85% excellent/good [8]                 - K-wire fixation
  - 10-20° extension lag acceptable           - Extension block technique
  - Functional outcome good                   - Screw fixation (large fragments)

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Non-Operative Management (First-Line for Majority)

Indications for Conservative Management

• Tendinous mallet (no fracture)
• Bony mallet with fragment less than 30% articular surface
• No volar subluxation
• Closed injury (open injuries may require wound closure then splinting)
• Presentation within 3 months (chronic cases can still be treated, though outcomes less predictable) [9]

Splinting Protocol: The Critical Component

Exam Detail: Splinting Principles (Evidence-Based):

The success of conservative management is entirely dependent on continuous immobilization in extension for sufficient duration to allow tendon/fracture healing. [4,5,9]

Key Evidence:

• Continuous splinting for 6 weeks achieves 70-85% excellent/good outcomes [8]
• ANY interruption in immobilization (even one episode of flexion) disrupts healing and requires restarting the 6-week period [9]
• Longer splinting (8 weeks) shows no significant improvement in outcomes vs 6 weeks for tendinous mallet [5]
• Bony mallet may benefit from 8 weeks to allow fracture consolidation [4]

Splinting Technique:

Splint Types

Recommended: Stack splint or alumafoam for initial management; consider custom thermoplastic if poor fit or skin issues.

Patient Instructions (Critical for Compliance)

Clinical Pearl: The "Golden Rules" for Splinting Success:

1. Wear 24/7 for entire 6-8 weeks – sleep, shower, all activities
2. Never let the DIP bend – even once resets the clock to day zero
3. Changing splint: Rest finger flat on table, remove old splint, immediately apply new one with DIP extended
4. Washing: Keep splint dry (plastic bag over hand in shower), or use waterproof splint
5. Move the PIP and MCP – exercise these joints actively to prevent stiffness
6. Skin checks: Daily inspection for redness, blisters, maceration (especially in finger creases)
7. If skin breaks down: Contact clinic immediately for splint adjustment
8. If DIP flexes: Inform clinician – may need to restart protocol

Follow-Up Schedule

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Surgical Management

Indications for Surgery

Exam Detail: Controversy: The 30% Threshold

While > 30% is widely cited, recent systematic reviews suggest outcomes may be acceptable with splinting even for fragments up to 40% if there is no volar subluxation. [7] The critical determinant is joint stability:

• No subluxation → trial of splinting reasonable even if 30-40% fragment
• Volar subluxation present → surgery required regardless of fragment size

Decision-making:

• less than 30% fragment, no subluxation → splinting (strong recommendation)
• 30-40% fragment, no subluxation → splinting trial with close review (weekly X-rays first 2-3 weeks)

• 40% fragment or ANY subluxation → surgery (strong recommendation)

Surgical Techniques

1. Extension Block Pinning (Ishiguro Technique)

2. Open Reduction Internal Fixation (ORIF)

3. Transfixion K-Wire Through DIP

4. Chronic Mallet/Swan-Neck Reconstruction

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Rehabilitation and Hand Therapy

Exam Detail: Role of Hand Therapy:

While splinting is the mainstay, hand therapy plays important roles:

During Splinting Phase:

• Fabrication of custom splints
• Education on splint application/removal technique
• Maintenance of PIP and MCP joint mobility (exercises while DIP splinted)
• Skin care and monitoring
• Compliance support

Post-Splinting Phase (weeks 8-12):

• Gentle active DIP range of motion exercises
• Progressive loading and strengthening
• Scar massage if surgical
• Functional task training
• Return to sport guidance

Evidence for Active Exercise: Recent RCT showed that active extension exercises during the splinting phase (performed within splint) may improve outcomes, though this requires specialized therapy input. [23]

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9. Complications

Early Complications (During Treatment)

Late Complications (Post-Treatment)

Exam Detail: Management of Residual Extensor Lag:

Acceptable vs Problematic:

• less than 15° lag: Functionally excellent, no treatment needed – most patients unaware [8]
• 15-30° lag: May be noticeable but functional; patient counseling, consider revision splinting if less than 6 months from injury
• > 30° lag: Problematic; swan-neck risk – consider surgery (tendon reconstruction or DIP fusion)

Surgical Options for Chronic Extension Lag:

1. Tendon reconstruction (Fowler tenotomy, spiral oblique ligament): For flexible lag
2. DIP arthrodesis (fusion in 0-10° extension): For stiff lag or arthritic joint – reliable pain relief and correction but loss of motion [24]

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10. Prognosis and Outcomes

Outcomes with Conservative Management

Overall Success Rates:

• Excellent outcome (full extension or less than 10° lag): 40-60% [8]
• Good outcome (10-20° lag, functionally normal): 25-35% [8]
• Fair outcome (20-30° lag, noticeable but acceptable): 10-15%
• Poor outcome (> 30° lag or swan-neck): 5-10%

Combined excellent + good outcomes: 70-85% – this is the figure quoted to patients as "success with splinting"

Exam Detail: Systematic Review Evidence (2023):

Comparative meta-analysis of surgical vs conservative management for mallet finger showed:

• No significant difference in residual extension lag between surgery and splinting for Type I mallet [25]
• Surgical complications (infection, hardware issues, stiffness) occurred in 15-20% vs 5-10% skin issues with splinting
• Conclusion: Splinting is first-line for closed mallet without large fracture/subluxation

Factors Predicting Better Outcomes:

• Early presentation (less than 2 weeks): 80% excellent/good vs 60% if > 4 weeks [9]
• Compliance with splinting: 85% vs 50% in non-compliant [9]
• Younger age (less than 40 years): Better tendon healing capacity
• Tendinous mallet: Slightly better than bony mallet (75% vs 70% excellent/good) [26]

Factors Predicting Poorer Outcomes:

• Delayed presentation (> 6 weeks)
• Non-compliance with splinting
• Volar subluxation (if managed conservatively)
• Elderly (> 70 years) – compliance and healing issues [13]
• Large bony fragments (> 30%)

Outcomes with Surgical Management

Key Point: Surgical management achieves similar functional outcomes to splinting for Type I injuries, but with higher complication rates. Surgery is reserved for unstable injuries where splinting will fail. [25]

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11. Prevention and Screening

Primary Prevention

Secondary Prevention (Preventing Complications)

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12. Key Guidelines and Evidence

Major Society Guidelines

Landmark Evidence

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13. Examination Focus

Common FRCS/Hand Surgery Exam Questions

1. Clinical Scenario: "A 25-year-old cricketer presents with a dropped ring fingertip after the ball struck it during a catch. Describe your assessment and management."

Viva Point: Model Answer: "This presentation is consistent with mallet finger – disruption of the terminal extensor tendon at the DIP joint. I would first confirm the diagnosis by examining for the pathognomonic finding of loss of active DIP extension with preserved passive extension, differentiating it from FDP avulsion (jersey finger) where active flexion is lost.

I would obtain a lateral radiograph of the finger to differentiate tendinous from bony mallet and assess for fracture fragment size and volar subluxation.

For a closed injury with no fracture or small fracture less than 30% articular surface, which represents 85% of cases, I would initiate continuous DIP extension splinting for 6-8 weeks. The splint must hold the DIP in 0-10 degrees hyperextension while keeping the PIP joint free. Critical patient education includes that any flexion episode during this period resets the healing clock.

If the X-ray showed a large fragment > 30% articular surface or volar subluxation, I would refer to hand surgery for consideration of surgical fixation, likely with extension block pinning or ORIF.

Expected outcomes with appropriate conservative management are 70-85% excellent or good results, with residual extension lag of 10-15 degrees being common and functionally acceptable."

2. Anatomy Question: "What structure is injured in mallet finger and what is its anatomical insertion?"

Answer: The terminal extensor tendon (confluence of the lateral bands of the extensor mechanism) is disrupted. It inserts onto the dorsal base of the distal phalanx, approximately 1-2mm distal to the articular margin, covering about 40% of the dorsal articular surface.

3. Classification Question: "Describe the Doyle classification of mallet finger."

Answer: [See Classification section above – Doyle Types I-IVC]

4. Management Controversy: "A patient presents with a bony mallet finger with a fracture fragment involving 35% of the articular surface but no volar subluxation. How would you manage this?"

Viva Point: Model Answer: "This represents Doyle Type IVB – a large fracture fragment at the threshold for surgical intervention. The critical decision factor is joint stability, specifically whether volar subluxation is present.

Since there is no subluxation, I would discuss two options with the patient:

Option 1 (My preference): Initial trial of conservative management with continuous DIP extension splinting for 8 weeks, with close radiographic follow-up (weekly X-rays for first 3 weeks) to monitor for development of subluxation. If subluxation develops, proceed to surgery.

Option 2: Surgical fixation with extension block pinning (Ishiguro technique) or ORIF to achieve anatomic reduction.

I would explain that recent evidence suggests fragments up to 40% may heal successfully with splinting if the joint remains reduced, though the 30% threshold is traditionally cited for surgery. The advantage of splinting is avoiding surgical risks (infection, hardware complications, stiffness), while surgery guarantees anatomic reduction.

The key is patient factors: A young athlete wanting to return to sport quickly might prefer surgery, while an elderly patient might prefer avoiding surgery if possible. Either approach is reasonable with appropriate informed consent."

5. Complication Question: "What is the most common late complication of untreated mallet finger?"

Answer: Swan-neck deformity – occurs in 20-30% of chronic untreated mallet fingers. The mechanism is extensor mechanism imbalance: loss of DIP extension shifts the extensor force proximally, causing PIP hyperextension combined with persistent DIP flexion. This creates the characteristic "swan-neck" appearance and requires surgical reconstruction (spiral oblique retinacular ligament reconstruction or DIP fusion). [10]

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Viva Key Points to Mention

Clinical Pearl: High-Yield Viva Facts:

1. Incidence: 9.4 per 100,000 per year – most common closed tendon injury of the hand [3]

2. "30% Rule": Fractures > 30% articular surface risk volar subluxation → surgery [6,7]

3. Splinting Duration: 6 weeks continuous for tendinous, 8 weeks for bony [4,5]

4. PIP Must Be Free: Immobilizing PIP causes stiffness and swan-neck deformity [20]

5. Passive Extension Intact: Distinguishes mallet (extensor disruption) from joint pathology

6. Residual Lag Acceptable: 10-15° extension lag occurs in 50-70% but is functionally excellent [8]

7. Surgery Indications: > 30% fragment with subluxation, failed conservative, chronic swan-neck [6,7,10]

8. Extension Block Pinning: Ishiguro technique – K-wire through middle phalanx to block DIP flexion [21]

9. Evidence: Cochrane review shows no benefit of surgery over splinting for Type I [4]

10. Differential: Jersey finger = opposite (can't flex DIP, tendon retracted) – requires urgent surgery

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Common Examination Mistakes

❌ Mistakes That Fail Candidates:

1. Confusing mallet and jersey finger – opposite deformities and opposite management
2. Recommending surgery for Type I mallet – evidence clearly supports conservative management first
3. Stating absolute 30% threshold for surgery – missing that subluxation is the key factor, not just fragment size
4. Forgetting to mention PIP must be free – PIP immobilization is a key error causing swan-neck
5. Not mentioning compliance importance – any flexion resets the clock (critical patient education point)
6. Quoting outdated splinting durations – 12 weeks is excessive; 6-8 weeks is evidence-based
7. Missing volar subluxation on X-ray – key indication for surgery

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14. Patient and Layperson Explanation

What is Mallet Finger?

Mallet finger happens when the tendon that straightens the tip of your finger gets injured or torn. This tendon is called the extensor tendon, and it attaches to the bone at the end of your finger. When it's damaged, you can't straighten the fingertip – it droops down and looks bent.

How Does It Happen?

The most common way is when a ball strikes your fingertip while playing sports like baseball, basketball, cricket, or volleyball. The force bends the fingertip suddenly while you're trying to straighten it, which tears the tendon. It can also happen from everyday activities like tucking in bedsheets or catching your finger on something.

Is It Serious?

Mallet finger is very common and usually not serious, but it does need proper treatment to heal correctly. If not treated, the finger can stay permanently bent and develop other problems later on.

What's the Treatment?

Most mallet fingers are treated with a splint – no surgery needed.

1. Splinting: Your fingertip will be placed in a small splint that holds it straight. You need to wear this splint 24 hours a day, 7 days a week for 6-8 weeks. This might sound like a long time, but it's necessary for the tendon to heal.

2. The most important rule: You cannot let your fingertip bend at all during those 6-8 weeks. If it bends even once, the healing has to start over from the beginning. That's why keeping the splint on all the time is so important.

3. Moving other joints: While your fingertip is in the splint, you should still move the other joints of your finger (the middle joint and knuckle) to keep them from getting stiff.

4. Surgery: Only needed in rare cases – if there's a large piece of bone broken off, or if the joint is unstable. Your doctor will tell you if you need surgery.

What Can You Expect?

• Success rate: About 70-85% of people get good to excellent results with splinting
• Some droop may remain: It's very common to have a small amount of droop left (5-15 degrees) even after proper treatment, but this is usually not noticeable and doesn't affect function
• Timeline: You'll wear the splint full-time for 6-8 weeks, then at nighttime only for another 2-4 weeks
• Return to activities: Most people can return to normal activities (including sports) after the splint comes off, usually around 10-12 weeks total

Tips for Success

✅ Do:

• Keep the splint on 24/7 for the full 6-8 weeks
• Change the splint carefully by resting your finger flat on a table
• Move your other finger joints to keep them from getting stiff
• Check your skin daily for redness or sores under the splint
• Keep the splint dry (use a plastic bag in the shower)

❌ Don't:

• Let your fingertip bend – even once means starting over
• Remove the splint to "test" if it's healed before your doctor says
• Get the splint wet (it will lose its shape)
• Ignore skin problems under the splint

What If I Don't Treat It?

If mallet finger is not treated, the finger may develop a swan-neck deformity, where the middle joint bends backward and the fingertip stays bent forward. This can make gripping things difficult and may eventually need surgery to fix.

Questions to Ask Your Doctor

• Do I need an X-ray? (Answer: Yes – to check if there's a fracture)
• How long exactly do I need to wear the splint?
• When can I return to sports or work?
• What should I do if my skin gets sore under the splint?
• What if the splint accidentally comes off?

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15. References

Primary Sources

1. Doyle JR. Extensor tendons – Acute injuries. In: Wolfe SW, Hotchkiss RN, Pederson WC, Kozin SH, eds. Green's Operative Hand Surgery. 6th ed. Philadelphia: Elsevier; 2011:159-188.

2. Handoll HH, Vaghela MV. Interventions for treating mallet finger injuries. Cochrane Database Syst Rev. 2004;(3):CD004574. doi:10.1002/14651858.CD004574.pub2. PMID: 15266538.

3. Clayton RA, Court-Brown CM. The epidemiology of musculoskeletal tendinous and ligamentous injuries. Injury. 2008;39(12):1338-1344. doi:10.1016/j.injury.2008.06.021

4. Pike J, Mulpuri K, Mok D, et al. Extension splinting for acute mallet finger: A systematic review. J Hand Surg Am. 2010;35(11):1857-1863. doi:10.1016/j.jhsa.2010.08.015. PMID: 21050650.

5. Long J, Gould JS. Long-term stack splint immobilization for closed tendinous mallet finger. J Hand Surg Am. 2020;45(7):680.e1-680.e7. doi:10.1016/j.jhsa.2019.12.012. PMID: 32531782.

6. Kalainov DM, Hoepfner PE, Hartigan BJ, Carroll C 4th, Genuario J. Nonsurgical treatment of closed mallet finger fractures. J Hand Surg Am. 2005;30(3):580-586. doi:10.1016/j.jhsa.2004.12.003

7. Bloom JM, Khouri JS, Hammert WC. Current concepts in the evaluation and treatment of mallet finger injury. Plast Reconstr Surg. 2013;132(4):560e-566e. doi:10.1097/PRS.0b013e31829ad369

8. Wehbe MA, Schneider LH. Mallet fractures. J Bone Joint Surg Am. 1984;66(5):658-669. PMID: 6373770.

9. Bendre AA, Hartigan BJ, Kalainov DM. Mallet finger. J Am Acad Orthop Surg. 2005;13(5):336-344. doi:10.5435/00124635-200509000-00007. PMID: 16148359.

10. Rosenthal EA, Elhassan BT. The treatment of chronic mallet finger deformity. Hand Clin. 2018;34(2):187-197. doi:10.1016/j.hcl.2017.12.008. PMID: 29526158.

11. Garberman SF, Diao E, Peimer CA. Mallet finger: results of early versus delayed closed treatment. J Hand Surg Am. 1994;19(5):850-852. doi:10.1016/0363-5023(94)90201-1

12. Smit JM, Beets MR, Zeebregts CJ, Rood A, Welters CF. Treatment options for mallet finger: a review. Plast Reconstr Surg. 2010;126(5):1624-1629. doi:10.1097/PRS.0b013e3181ef8ec8

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