PRC Wrist Surgery: Procedure, Recovery, and Functional Outcomes

What is PRC Wrist Surgery?

Proximal Row Carpectomy (PRC) is a surgical procedure that involves the removal of three carpal bones—the scaphoid, lunate, and triquetrum—from the proximal (closest to the forearm) row of the wrist, primarily performed to alleviate pain and preserve motion in cases of significant wrist arthritis or injury.

What is Proximal Row Carpectomy (PRC)?

Proximal Row Carpectomy (PRC) is a well-established surgical technique in orthopedics designed to address chronic pain and dysfunction stemming from advanced arthritis or severe injury within the wrist joint. Unlike more extensive procedures like total wrist fusion, PRC aims to maintain a degree of wrist motion while effectively eliminating the primary source of pain. It achieves this by excising the carpal bones most frequently involved in degenerative processes, particularly those that articulate with the radius and contribute significantly to wrist instability or pain.

Anatomy of the Wrist: A Brief Overview

To understand PRC, a basic grasp of wrist anatomy is essential. The wrist is a complex joint formed by the articulation of the forearm bones (radius and ulna) with eight small carpal bones, arranged into two rows:

• Proximal Row: Consists of the scaphoid, lunate, triquetrum, and pisiform (the pisiform sits anterior to the triquetrum and is often excluded from functional discussions of the row). These bones articulate directly with the radius, forming the radiocarpal joint.
• Distal Row: Composed of the trapezium, trapezoid, capitate, and hamate. These bones articulate with the metacarpals of the hand.

In a PRC, the scaphoid, lunate, and triquetrum are removed. This effectively converts the radiocarpal joint into a new articulation between the capitate bone of the distal row and the radius, with the hamate also articulating with the radius. This new articulation is critical for the preserved motion.

Indications for PRC Surgery

PRC is typically considered when conservative treatments (e.g., splinting, anti-inflammatory medications, injections, physical therapy) have failed to provide adequate relief. Key indications include:

• Scapholunate Advanced Collapse (SLAC) Wrist: The most common indication. This condition arises from chronic instability and degeneration of the scapholunate ligament, leading to progressive arthritis between the scaphoid, lunate, capitate, and radius.
• Scaphoid Nonunion Advanced Collapse (SNAC) Wrist: Occurs when an untreated or poorly healed scaphoid fracture leads to a collapse of the carpal architecture and subsequent arthritis.
• Kienböck's Disease: Avascular necrosis (death of bone tissue due to lack of blood supply) of the lunate bone, leading to its collapse and subsequent arthritis.
• Post-traumatic Arthritis: Arthritis resulting from other significant wrist injuries.
• Degenerative Arthritis: Less commonly, primary osteoarthritis of the radiocarpal joint that specifically involves the proximal row.

The primary goal is to alleviate pain, particularly with loaded activities, while preserving functional wrist motion.

The Proximal Row Carpectomy Procedure

The PRC procedure is performed by an orthopedic hand surgeon, often under regional or general anesthesia.

• Incision: A dorsal (back of the hand) incision is typically made over the wrist.
• Exposure: The extensor tendons are carefully retracted to expose the carpal bones.
• Bone Excision: The scaphoid, lunate, and triquetrum bones are meticulously identified and carefully removed. The pisiform, being a sesamoid bone within the flexor carpi ulnaris tendon, is usually left intact.
• Joint Preparation: The surgeon may smooth any rough edges of the remaining carpal bones (capitate, hamate) and the radius to create a more congruent articulating surface.
• Closure: The wound is irrigated, and the layers are closed. A splint or cast is applied to immobilize the wrist post-operatively.

The underlying principle is to remove the "diseased" or arthritic bones of the proximal row, allowing the healthy capitate (and hamate) to articulate directly with the radius, creating a new, pain-free joint.

Post-Operative Recovery and Rehabilitation

Recovery from PRC surgery is a structured process crucial for optimal outcomes.

• Immobilization: The wrist is typically immobilized in a cast or splint for 4-6 weeks to allow initial healing and soft tissue recovery.
• Early Mobilization: Once the initial immobilization period is over, a structured physical therapy program begins. This often involves:
  • Range of Motion (ROM) Exercises: Gentle active and passive exercises to restore wrist flexion, extension, radial deviation, and ulnar deviation.
  • Forearm Rotation: Exercises for pronation and supination.
  • Grip Strengthening: Gradual introduction of grip exercises as pain allows.
• Progressive Strengthening: As pain subsides and ROM improves, progressive strengthening exercises for the wrist and forearm muscles are introduced to improve stability and functional capacity.
• Return to Activity: Light activities can typically resume within 3-4 months, with more strenuous activities and weight-bearing potentially taking 6 months to a year or more. Full recovery can take up to 12-18 months.

Adherence to the rehabilitation protocol is paramount for achieving the best possible pain relief and functional range of motion.

Expected Outcomes and Potential Complications

Expected Outcomes:

• Pain Relief: The primary goal, often achieved significantly.
• Preserved Motion: While not full pre-injury motion, a functional range of motion (typically 50-70% of normal) is usually maintained, allowing for most daily activities.
• Improved Grip Strength: Often improves as pain decreases and strength training progresses.

Potential Complications: While generally safe, like any surgery, PRC carries potential risks:

• Infection: Risk at the surgical site.
• Nerve Injury: Damage to superficial or deep nerves in the wrist, potentially leading to numbness or weakness.
• Persistent Pain: Though rare, some patients may not achieve complete pain relief.
• Stiffness: Adhesions or inadequate rehabilitation can lead to restricted motion.
• Progression of Arthritis: While PRC removes the most problematic bones, arthritis can, in rare cases, develop in the newly formed radiocapitate joint over many years.
• Complex Regional Pain Syndrome (CRPS): A rare but severe chronic pain condition.

PRC vs. Wrist Arthrodesis (Fusion): A Comparison

When considering surgical options for severe wrist arthritis, PRC is often contrasted with wrist arthrodesis (fusion).

• Proximal Row Carpectomy (PRC):

  • Goal: Pain relief with preservation of some wrist motion.
  • Mechanism: Removes diseased bones, creating a new mobile joint.
  • Outcome: Typically 50-70% of normal motion, excellent pain relief.
  • Recovery: Faster initial recovery, but full return to strenuous activity still takes time.
  • Limitations: May not be suitable for all types or severe forms of arthritis.

• Wrist Arthrodesis (Fusion):

  • Goal: Complete pain relief by eliminating all wrist motion.
  • Mechanism: Fuses the carpal bones and/or radius to create a single, rigid bone.
  • Outcome: Complete elimination of wrist flexion/extension, radial/ulnar deviation. Forearm rotation (pronation/supination) is preserved. Excellent pain relief.
  • Recovery: Longer immobilization, but once fused, the wrist is very stable and strong for heavy loading.
  • Limitations: Permanent loss of wrist motion, which can impact certain activities requiring wrist flexibility.

The choice between PRC and fusion depends on the specific pathology, patient's functional demands, and surgeon's preference. PRC is generally favored when preserving motion is a priority and the joint surfaces are suitable.

Functional Considerations for Movement and Exercise

For fitness enthusiasts, personal trainers, and kinesiologists, understanding the functional implications of PRC is crucial:

• Range of Motion (ROM): Patients will regain a functional ROM, but it will not be full. Expect limitations, especially in extreme flexion and extension. This impacts exercises requiring significant wrist mobility, such as push-ups, burpees, certain Olympic lifts, or deep stretches.
• Grip Strength: While initial grip strength may be reduced, it typically improves significantly with rehabilitation. Functional grip for daily activities and moderate lifting is usually restored.
• Weight Bearing: Gradual and progressive weight-bearing exercises are essential. Initially, modified exercises that offload the wrist (e.g., using dumbbells for push-ups, or performing exercises on knuckles or forearms) may be necessary.
• Proprioception and Stability: The surgical alteration of the wrist joint can affect proprioception (the sense of joint position). Specific exercises focusing on controlled movements and stability will be vital in rehabilitation.
• Exercise Modification:
  • Upper Body Pushing: Modify push-ups, bench press, overhead press to reduce direct wrist stress. Consider neutral grip dumbbells, push-up handles, or machine exercises.
  • Upper Body Pulling: Generally well-tolerated, but heavy gripping might initially be challenging.
  • Impact Activities: Activities involving high impact or repetitive wrist loading (e.g., boxing, gymnastics, heavy weightlifting) should be approached cautiously and progressively, often with specific bracing or taping.
  • Sport-Specific Training: Return to sports requires careful, progressive drills mimicking the demands of the activity.

The key is to listen to the body, respect pain signals, and work closely with a physical therapist to gradually reintroduce and modify exercises, ensuring long-term wrist health and function.

Conclusion

Proximal Row Carpectomy (PRC) is a valuable surgical intervention for individuals suffering from chronic, debilitating wrist pain due to advanced arthritis or specific carpal injuries. By selectively removing the scaphoid, lunate, and triquetrum, PRC aims to provide significant pain relief while preserving a functional range of motion, offering a viable alternative to wrist fusion. A thorough understanding of the procedure, its potential outcomes, and the critical role of post-operative rehabilitation is essential for optimizing recovery and enabling individuals to return to a high quality of life with improved wrist function.