Introduction 

Mallet finger is a torn extensor tendon of the distal interphalangeal (DIP) joint, causing the fingertip to droop naturally. The injury is commonly sports-related. Standard treatment typically involves continuous use of a splint for about 6-8 weeks. Other methods of healing include surgery, which is typically reserved for complex cases where the joint is severely misaligned or a large bony fragment has been avulsed.¹

During recovery, some complications may arise that could hinder optimal finger restoration. Prolonged splint use can lead to skin maceration, joint stiffness from poor positioning, infection, and impede natural healing. This article explores how these complications occur, their causes, and management strategies to ensure the best possible outcome.²

Overview of mallet finger and its management 

Mallet finger is caused by a sudden forced flexion of an extended fingertip. It is also called “baseball finger” due to its association with sports injuries. According to Doyle’s Classification, mallet finger can be divided into four different types:^1,2

Type 1: Closed tendinous injury

• The tendon is injured without a fracture
• Common location: DIP
• Caused by forced flexion, resulting in drooping
• Managed non-surgically with splints

Type 2: Open tendinous injury (laceration)

• Laceration splits the extensor tendon
• Requires surgical repair

Type 3: Open injury with skin and tendon loss

• Tendon and tissue loss
• Surgical repair and skin grafting are required

Type 4: Bony mallet finger

• Type 4a: In children, injury through the growth plate (Salter-Harris fracture)
• Type 4b: In adults, 20% to 50% of the articular surface is fractured
• Type 4c: In adults, > 50% of the articular surface is fractured, often with DIP joint subluxation

Treatment of this condition usually involves wearing a specialised splint 24/7 for 6–8 weeks to prevent tendon gap formation. Unstable bony injuries may require surgical management such as pinning or screw fixation. Patient compliance is also crucial; even minimal DIP flexion can disrupt healing. Education and adherence to instructions help prevent complications.³

Skin complications and breakdown

The most common complications are skin-related issues. Poorly fitted splints may compromise skin integrity and recovery. Other contributing factors include:^1-3

• Continuous pressure and friction from ill-fitting splints
• Excess moisture or poor hygiene leading to skin maceration
• Higher susceptibility in elderly, diabetic patients, or those with dermatological conditions

Early intervention involves modifying or temporarily removing the splint, appropriate padding, and maintaining clean, dry skin. Severe cases may require temporary discontinuation of splinting.

Joint stiffness and reduced range of motion 

Concerns regarding joint stiffness and reduced range of motion may arise after the treatment for mallet finger. The DIP joint is the primary site of injury and the location for splint application. It is vulnerable to stiffness as it stays in the same position for a while. If the finger extends too far, it may affect the proximal interphalangeal (PIP) joint. Joint capsule tightness and tendon adhesions occur when there is prolonged immobilisation. This can lead to discomfort and mechanical limitation.²

Risk factors include rigid or improperly positioned splints. Rehabilitation strategies, including passive movement and exercises for unaffected joints, are essential. Gradual mobilisation post-splint removal restores function, avoiding long-term stiffness and loss of finger function.^2,4

An example of an effective management strategy is hand therapy, which focuses on the gentle exercises tailored to the patient's needs. To progress further, patients have the option for early rehabilitation to identify the problem and any other concerns about the finger’s functionality.⁵

Infection risks during treatment

Infection is a potential risk during a mallet finger treatment. Beneath the splint, the skin can break down and accumulate moisture and pathogenic bacteria. Common bacteria include Staphylococcus aureus and Streptococcus species. Both of these live naturally on our skin; however, when the skin barrier is compromised, they become pathogenic.⁶

Some signs to look out for are redness, heat, swelling, and discharge. In rare cases, an uncommon fever may arise, indicating a more serious infection. That is why you should be wary of any open wounds in the splint.⁷

Management depends on severity:^1,7

• Mild infections: Topical antibiotics and wound care
• Moderate infections: Oral antibiotics or temporary splint discontinuation
• Severe infections: Surgical debridement

Preventive strategies focus on hygiene, regular skin inspections, and patient education.

Surgical complications

Surgery is rare for this condition. It is typically reserved for specific scenarios, like large avulsions, joint subluxation, or cases where the splint was not helpful in the healing process. Possible complications include:^1,2,7

• Surgical site infection and post-operative hygiene challenges
• Hardware irritation or migration of the splint
• Nail bed injury causing deformities
• Post-operative joint stiffness

Hand therapy and rehabilitation post-surgery are crucial for restoring movement and strength. Surgical intervention is effective when indicated, but compliance and rehabilitation determine functional outcomes.⁵

Patient compliance and education

Patient compliance is also critical. Delayed healing often results from premature splint removal, inadequate hygiene, or incorrect positioning. Patients must maintain uninterrupted splint use for 6–8 weeks.³

Regular doctor reminders and follow-up appointments foster good habits, enhance functional outcomes, and minimise long-term disability.

Summary

Mallet finger is a torn extensor tendon of the DIP joint, which causes the fingertip to droop naturally. It heals successfully with proper management and care. However, complications like skin breakdown and infection are not uncommon and may delay recovery. Causes often include poor splint fitting, hygiene lapses, and irregular follow-ups. Prevention through correct splinting, regular skin assessments, and patient education is essential. Early identification and intervention facilitate successful recovery and minimise the need for more invasive treatments.