Basal Joint Surgery: Procedures, Recovery, and Outcomes

What is basal joint surgery called?

Basal joint surgery refers to a range of surgical procedures primarily performed to treat osteoarthritis of the thumb carpometacarpal (CMC) joint, often broadly termed thumb CMC arthroplasty or basal joint arthroplasty. While there isn't one single name, the most common specific procedure is a trapeziectomy, often combined with ligament reconstruction.

Understanding the Basal Joint and Its Condition

The basal joint, formally known as the carpometacarpal (CMC) joint of the thumb, is located at the base of the thumb, where the metacarpal bone of the thumb connects to a small wrist bone called the trapezium. This joint is crucial for the thumb's wide range of motion, enabling pinching, grasping, and opposition – movements essential for daily activities.

Basal Joint Arthritis (Rhizarthrosis) Like other joints, the basal joint is covered with articular cartilage, which allows bones to glide smoothly. With age, repetitive stress, or injury, this cartilage can wear away, leading to osteoarthritis. This condition, often called basal joint arthritis or thumb CMC arthritis, results in:

• Pain: Especially with pinching, gripping, or twisting motions.
• Stiffness: Limiting thumb movement.
• Swelling: Around the base of the thumb.
• Weakness: Difficulty with fine motor tasks.
• Deformity: In advanced stages, the thumb may appear "squared" or subluxed.

When conservative treatments such as splinting, medication, injections, and physical therapy no longer provide adequate relief, surgical intervention may be considered.

Common Surgical Procedures for Basal Joint Arthritis

The specific name of basal joint surgery depends on the technique employed by the hand surgeon. Here are the most common procedures:

• Trapeziectomy: This is the most frequently performed surgery for basal joint arthritis. The procedure involves the complete removal of the trapezium bone. By removing the arthritic bone, the source of pain is eliminated. The space left behind often fills with scar tissue, forming a "pseudoarthrosis" (false joint).
• Ligament Reconstruction Tendon Interposition (LRTI): Often performed in conjunction with a trapeziectomy, LRTI aims to stabilize the thumb metacarpal and prevent it from collapsing into the space left by the removed trapezium. A tendon, usually a portion of the flexor carpi radialis (FCR) or palmaris longus tendon, is harvested from the patient's forearm. This tendon is then used to:
  • Reconstruct the torn ligaments: Providing stability to the thumb.
  • Interpose into the space: Creating a cushion between the bones to prevent rubbing and preserve thumb length.
• Fusion (Arthrodesis): This procedure involves permanently fusing the thumb metacarpal bone to the trapezium bone, creating a single, solid bone. While it provides excellent pain relief and stability, it eliminates all movement at the basal joint. This option is typically reserved for younger, active individuals who require strong pinch and grip, or in cases where other surgeries have failed, as it sacrifices mobility.
• Joint Replacement (Arthroplasty): Similar to hip or knee replacements, this involves removing the damaged joint surfaces and replacing them with an artificial implant. These implants can be made of silicone, pyrocarbon, or metal. While designed to restore motion and reduce pain, implant arthroplasty is less common for the thumb CMC joint compared to trapeziectomy due to potential issues with implant loosening or wear over time.
• Osteotomy: In rare cases, for very early-stage arthritis or specific deformities, an osteotomy may be performed. This involves cutting and reshaping the bone (typically the thumb metacarpal) to realign the joint and redistribute pressure, aiming to preserve the joint rather than remove it.

Deciding on Basal Joint Surgery

The decision to undergo basal joint surgery is made in consultation with a qualified hand surgeon. It is typically considered when:

• Conservative treatments have failed: Non-surgical options no longer alleviate pain or improve function.
• Pain significantly impacts daily life: The arthritis interferes with work, hobbies, or basic activities.
• Imaging confirms significant joint degeneration: X-rays show advanced cartilage loss or bone spurs.

The surgeon will evaluate the extent of arthritis, the patient's age, activity level, and specific needs to recommend the most appropriate surgical technique.

The Surgical Process: What to Expect

The surgical process for basal joint arthritis generally follows a structured path:

• Pre-Operative Assessment: This includes a thorough medical history, physical examination, imaging (X-rays), and discussion of the surgical plan, potential risks, and expected outcomes.
• The Procedure: Basal joint surgery is typically performed as an outpatient procedure, meaning the patient goes home the same day. It is usually done under regional anesthesia (e.g., an arm block) with sedation, or general anesthesia. The surgery involves an incision at the base of the thumb to access the joint and perform the chosen procedure.
• Post-Operative Care and Rehabilitation: This phase is critical for successful recovery.
  • Immobilization: The hand and thumb will be immobilized in a cast or splint for several weeks (typically 4-6 weeks) to allow for initial healing.
  • Pain Management: Medications will be prescribed to manage post-operative pain.
  • Physical or Occupational Therapy: Once the initial immobilization period is over, a structured rehabilitation program is essential. This includes exercises to restore range of motion, strengthen the thumb and hand, and improve functional use. Therapy typically continues for several months.

Potential Risks and Considerations

As with any surgical procedure, basal joint surgery carries potential risks, including:

• Infection: Though uncommon, it's a possibility.
• Nerve damage: Leading to numbness or weakness.
• Tendon complications: Such as rupture or adhesion.
• Persistent pain: While the goal is pain relief, some discomfort may remain.
• Stiffness: Despite therapy, some degree of stiffness can persist.
• Complex Regional Pain Syndrome (CRPS): A rare but serious chronic pain condition.
• Failure of the procedure: Requiring further intervention.

Full recovery and return to normal activities can take several months, often 3 to 6 months, and sometimes up to a year for complete strength and comfort. Adherence to the post-operative rehabilitation protocol is paramount for optimal outcomes.

Long-Term Outcomes and Quality of Life

For most patients, basal joint surgery, particularly trapeziectomy with or without LRTI, provides significant pain relief and improved function, leading to a substantial enhancement in quality of life. While complete restoration of pre-arthritic function is not always possible, patients typically experience a dramatic reduction in pain and are able to perform daily activities with greater ease. Long-term studies generally support the efficacy and durability of these procedures for managing thumb CMC joint arthritis.