Ligament reconstruction and tendon interposition (LRTI) is a type of surgery for treating arthritis of the thumb, a common type of arthritis in the hand.

LRTI surgery may be suitable for people with moderate to severe thumb arthritis. Many people experience an improvement in symptoms following this surgery, although complications can occur.

This article explains the purpose of LRTI surgery, who it benefits, and what to expect from the procedure and recovery.

Joints form where two bones meet. Smooth tissue known as cartilage lines your joints. Cartilage permits free movement of one bone against another. In arthritis, the cartilage deteriorates and may no longer cushion the bones.

The problem may start when the strong tissue (a ligament) that holds the joint together loosens up. This allows the bones to slip out of place, causing wear to the cartilage.

LRTI surgery removes a small bone, called the trapezium, at the base of the thumb and rearranges a nearby tendon to serve as a cushion for the arthritic thumb joint.

A surgeon will also remove a portion of the damaged ligament and replace it with a piece of your wrist flexor tendon.

The technical name for arthritis of the thumb is basal joint arthritis.

Doctors may recommend LRTI for adults with moderate to severe basal joint arthritis who have difficulty pinching or gripping with their thumb.

LRTI has been around since the 1970s. According to an older review, doctors initially only considered people older than 50 years for the procedure. Since then, it has become more common to treat younger age groups.

To understand the LRTI procedure, it’s important to understand the anatomy of your thumb.

Anatomy of the thumb

Examine your thumb, and you’ll feel two bones, known as phalanges. But there’s a third bone in the fleshy part of your hand known as the metacarpal. The metacarpal connects the longer, second bone of your thumb to your wrist.

The bones of your thumb have three joints:

  • Interphalangeal (IP) joint: This is the first joint, near the tip of your thumb.
  • Metacarpophalangeal (MP) joint: This is the second joint, where the second bone of the thumb meets the bone of the hand (metacarpal).
  • Carpometacarpal (CMC) joint: This is the third joint, where the metacarpal bone meets the trapezium bone of your wrist.

The CMC has more freedom of motion than any other finger joint. It allows the thumb to bend, extend, move toward and away from the hand, and spin around. This explains why it’s painful to pinch or grip when you have thumb arthritis.

At the base of the thumb is the trapezium bone. It’s called that because it has a trapezoid shape. It’s one of eight bones that make up the complex structure of your wrist.

One more joint to consider is the one where the trapezium meets the other part of the wrist. This is called the scaphotrapeziotrapezoidal (STT) joint. It can also have arthritis along with the CMC joint.

What the LRTI procedure does

There are many ways to carry out LTRI surgery. One method is as follows: a surgeon removes all or part of the trapezium bone from the wrist and smooths out the remaining surfaces of the CMC and STT joints.

They make an incision in your forearm and cut the FCR (flexor carpi radialis) tendon, which allows you to bend your wrist.

They drill a hole in the metacarpal bone of the thumb and pass through the free end of the FCR tendon, sewing it back onto itself.

They cut off the remaining portion of the FCR and preserve it in gauze. Following this, they use part of the tendon tissue to reconstruct the ligament of the CMC joint and roll up the other, longer portion into a coil called an anchovy.

They place the “anchovy” in the CMC joint to give the cushioning that the arthritic cartilage used to provide. An artificial anchovy can also eliminate the need to harvest a tendon.

To maintain the proper positioning of the thumb and wrist, a surgeon places specialized wires or pins, known as Kirschner (K-wires), in the hand. These protrude from the skin, and the surgeon will usually remove them about four weeks after surgery.

This procedure may occur under a type of anesthesia known as regional axillary block, so you won’t feel pain. It may also happen under general anesthesia.

Many people experience pain relief after LRTI surgery. David S. Ruch, professor of orthopedic surgery at Duke University in North Carolina, says LRTI has a 96% success rate, with results lasting up to 20 years.

However, the recovery time following this procedure can be long and painful. People can experience adverse effects following LRTI surgery, including:

  • ongoing pain
  • paresthesia — atypical skin sensations, such as pins and needles or burning
  • thickening nerve tissue
  • scar tenderness
  • infection
  • tendon dysfunction

Some complications and adverse effects following LRTI surgery may require additional procedures and operations to fix.

A 2022 review compared the outcomes of LRTI and suture-button suspensionplasty (SBS) for treating osteoarthritis of the hand.

Both procedures had similar symptomatic improvements and complication rates. However, the researchers note that the studies on SRS procedures were of lower quality than those discussing LRTI.

More research is necessary to compare the outcomes of LRTI with other surgical procedures for hand arthritis to understand the potential for risks and the difference in outcomes.

Doctors may use a regional axillary block anesthetic for LRTI. They administer this around the brachial plexus nerves, where it passes through the underarm. It provides the advantage of continued pain relief after the operation.

You may awake from sedation with nausea, but you’re typically able to return home the same day.

First month

After surgery, doctors will apply a splint that you’ll wear for at least the first week. At the end of the week, they may transfer you to a cast. Or, you may keep the splint alone for a full month after surgery.

You must elevate your hand at all times during the first month. Your doctor might recommend a foam wrist-elevation pillow or other device. Slings aren’t always suitable, as they may lead to shoulder stiffness.

After one or two weeks, a doctor may change the dressing on the surgical wound.

Your doctor may give you range-of-motion exercises for your fingers and thumb to perform over the first month.

Second month

After four weeks, your doctor will remove the K-wires and stitches.

You’ll get a thumb splint known as a spica splint, which attaches to your forearm.

Your doctor may prescribe a physical therapy program that emphasizes range of motion and strengthening of the wrist and forearm using isometric exercises.

Third to sixth month

By the start of the third month, you’ll begin a gradual return to typical daily activity. The doctor may wean you off the splint and encourage you to start gentle activities with the affected hand. These may include

  • tooth brushing
  • other personal hygiene activities
  • eating
  • writing

Therapy may include squeezing and manipulating special hand putty to strengthen your fingers and thumb. The putty comes in graduated resistance levels to use as your strength increases.

Return to work

The speed at which you can return to work will depend on the type of job you have.

People in white collar and executive positions may be able to return to work within a week. But it can take as long as three to six months before returning to a job that requires extensive use of your hands.

It’s best to follow the advice of your healthcare team when it comes to understanding when you can return to work.

LRTI is a serious surgery with a lengthy recovery time. It can provide effective relief from thumb arthritis symptoms for many people. However, complications like ongoing pain can occur.

LRTI surgery isn’t suitable for everyone. Doctors may only recommend it for people with moderate to severe thumb arthritis and difficulty with certain hand movements.

It’s important to follow your doctor’s guidance on recovery, and avoid extensive use of the affected hand until they advise it’s okay.