Volar Plate Arthroplasty: Procedure, Recovery, and Outlook for Finger Joint Stability

What is a Volar Plate Arthroplasty?

A volar plate arthroplasty is a specialized surgical procedure primarily performed to address chronic instability, hyperextension deformities, or contractures of the proximal interphalangeal (PIP) joint in the finger, focusing on the repair, reconstruction, or advancement of the volar plate ligament to restore joint stability and function.

Understanding the Volar Plate and Finger Anatomy

To grasp a volar plate arthroplasty, it's essential to first understand the anatomy of the finger's PIP joint. The PIP joint is the middle knuckle of the finger, crucial for fine motor skills and grip. It is a hinge joint, allowing primarily flexion and extension.

The volar plate is a thick, fibrous, ligamentous structure located on the palmar (front) side of the PIP joint. Its primary functions include:

• Preventing hyperextension: It acts as a checkrein, stopping the finger from bending backward too far.
• Stabilizing the joint: It provides crucial support to the PIP joint, especially during gripping and pinching.
• Protecting tendons: It forms the floor of the flexor tendon sheath, protecting the tendons that bend the finger.

Injuries to the volar plate, often resulting from hyperextension (e.g., a "jammed finger"), can lead to chronic instability, pain, and sometimes the development of a hyperextension deformity, where the joint rests in an abnormally extended position. Conversely, long-standing inflammatory conditions or trauma can lead to contractures, where the joint becomes stiff and unable to fully extend.

What is a Volar Plate Arthroplasty?

A volar plate arthroplasty is a surgical intervention aimed at restoring the structural integrity and functional biomechanics of the PIP joint by specifically addressing issues with the volar plate. Despite the term "arthroplasty" (which often implies joint replacement), this procedure typically involves the repair, reconstruction, or advancement of the existing volar plate or surrounding soft tissues, rather than replacing the entire joint with an artificial implant.

The goal is to reinforce the palmar aspect of the joint, preventing unwanted hyperextension or improving extension in cases of contracture, thereby enhancing joint stability and improving the range of motion.

Why is a Volar Plate Arthroplasty Performed?

This specialized procedure is indicated when conservative treatments (such as splinting, physical therapy, and anti-inflammatory medications) have failed to adequately address the patient's symptoms. Common indications include:

• Chronic PIP joint hyperextension deformity: Often seen after a severe "jammed finger" injury where the volar plate has been torn or stretched, leading to persistent backward bending of the joint.
• PIP joint instability: Lingering looseness or "giving way" of the joint, making it difficult to perform daily tasks or participate in sports.
• Post-traumatic arthritis with instability: While not a primary treatment for advanced arthritis, it can be considered if instability is a significant component of the joint's dysfunction after trauma.
• PIP joint flexion contracture: In some cases, a volar plate release or lengthening may be performed as part of an arthroplasty to improve extension in a stiff joint.
• Volar plate avulsion fracture: When the volar plate tears away a small piece of bone from the finger.

The Surgical Procedure

The specific technique for a volar plate arthroplasty varies depending on the underlying pathology and the surgeon's preference, but generally involves:

• Incision: A small incision is made on the palmar side of the finger, typically over the PIP joint.
• Joint Exposure: The surgeon carefully navigates through the tissues to expose the PIP joint and the volar plate.
• Repair/Reconstruction:
  • Volar Plate Advancement: If the volar plate is stretched or lax, it may be detached from its proximal insertion and reattached further distally on the bone to tighten it and prevent hyperextension.
  • Capsulodesis: Tightening of the joint capsule to provide stability.
  • Tendon Graft: In severe cases where the volar plate is significantly damaged or absent, a small tendon graft (often from the wrist or toe) may be used to reconstruct the ligament.
  • Release/Lengthening: For contractures, the volar plate and surrounding tight tissues may be carefully released or lengthened to allow greater extension.
• Closure: The incision is closed, and a protective dressing or splint is applied.

The procedure aims to restore the anatomical integrity of the volar plate, ensuring it can effectively limit hyperextension and provide stability to the PIP joint.

Post-Operative Recovery and Rehabilitation

Rehabilitation is a critical component of a successful outcome after volar plate arthroplasty. It is typically guided by a certified hand therapist or physical therapist.

• Initial Immobilization (0-3 weeks): The finger is usually immobilized in a splint or cast to protect the surgical repair and allow initial healing. The position of immobilization (e.g., slight flexion or extension) will depend on the specific procedure performed.
• Early Motion (3-6 weeks): Under the guidance of a therapist, gentle, controlled range of motion exercises begin. The focus is on regaining flexion and extension without stressing the repair. Active and passive exercises are carefully introduced.
• Strengthening (6-12+ weeks): As stability improves, progressive strengthening exercises are incorporated to rebuild grip strength and finger dexterity. Scar management techniques (massage, silicone sheets) are also important to prevent stiffness.
• Return to Activity: Light activities can typically resume within 8-12 weeks, with a gradual return to more strenuous activities and sports over 3-6 months, depending on the individual's progress and the demands of their activities.

A kinesiologist or exercise science professional plays a vital role in designing and supervising the rehabilitation program, ensuring proper progression, biomechanical efficiency, and safe return to function.

Potential Risks and Complications

As with any surgical procedure, volar plate arthroplasty carries potential risks, including:

• Infection: Though rare, any surgical site can become infected.
• Bleeding: Post-operative hematoma formation.
• Nerve Damage: Injury to the small nerves in the finger, leading to numbness or altered sensation.
• Stiffness (Arthrofibrosis): Despite meticulous rehabilitation, some degree of residual stiffness can occur.
• Persistent Pain: Pain may continue if the underlying issue is not fully resolved or if complications arise.
• Recurrence of Instability/Deformity: The repair may fail, leading to a return of the original problem.
• Complex Regional Pain Syndrome (CRPS): A rare but severe chronic pain condition that can affect the hand after trauma or surgery.
• Scar Sensitivity: The surgical scar can be tender or sensitive.

Outlook and Long-Term Considerations

The long-term outlook following a volar plate arthroplasty is generally favorable, particularly for patients who adhere diligently to their post-operative rehabilitation program. Most individuals experience significant improvement in joint stability, reduction in pain, and restoration of functional range of motion.

Factors influencing the outcome include the severity of the initial injury, the specific surgical technique used, the patient's overall health, and their commitment to physical therapy. While the goal is to restore full function, some individuals may experience minor residual stiffness or mild limitations, especially in high-demand activities. Ongoing adherence to hand exercises and protective strategies can help maintain the surgical outcome over time.