Comparative Effectiveness of the Two Splints in Trigger Finger

Treatment of Trigger Finger With Metacarpophalangeal Joint Blocking Orthosis Versus Relative Motion Extension Orthosis

RME orthosis is recommended for the treatment of trigger finger. However, its efficacy has not been studied in trigger finger patients. Given the increasing popularity of this orthosis among clinicians, it is important to evaluate their effectiveness to provide evidence for its use in trigger finger. The purpose of this study was to compare the efficacy of a 6-week orthotic intervention in a randomly selected group of patients with trigger finger using MCP-blocking and RME orthoses.

Generally, three types of orthoses are used in the treatment of trigger finger. Some authors used MCP blocking orthosis, while others used DIP or PIP blocking orthosis. Comparative studies are quite limited, as only one study comparing two orthotic designs found that the MCP blocking orthosis was more effective than the DIP blocking orthosis.The MCP blocking orthosis, which restricts the MCP joint to 10-15° of flexion, is commonly used in the conservative treatment of trigger finger.An RME orthosis could be an alternative orthotic treatment option for trigger finger because it holds the MCP in an extended position. The RME orthosis is thought to prevent flexion of the affected finger, thereby limiting tendon glide. This reduces the pressure on the A1 pulley, allowing the tendon to glide more smoothly, reducing the likelihood of triggering. Despite limiting motion,the orthosis still allows the patient to perform daily activities with the orthosis. Therefore, positioning the MCP joint in extension could provide additional benefits in trigger finger. The relative motion orthosis is a new orthotic design that positions the affected finger in 10-15 degrees of extension relative to the adjacent fingers.It also has several advantages, including small size, low-profile design, easy and inexpensive fabrication, and better patient compliance. The primary objective of this study was to compare the efficacy of a 6-week orthotic intervention for pain relief in a randomly selected group of patients with TF using the MCP blocking orthosis and the RME orthosis. The secondary objective was to determine the comparative effectiveness of the orthoses on function and satisfaction with the orthosis.

Patients were randomly assigned in a 1:1 ratio to either the MCP-blocking orthosis group or the RME orthosis group, using a simple random sampling method.

The custom MCP blocking orthosis was made of a 1.6-mm-thick thermoplastic material that extends from the palm over the MCP joint and includes a ring around the proximal phalanx. It is designed to block the MCP joint in flexion of 10°-20° while allowing full range of motion of the proximal and distal interphalangeal joints.

The RME orthosis was fabricated from 3.2-mm-thick thermoplastic material with the affected finger positioned at an extension of approximately 10°-20° relative to the adjacent fingers.

Inclusion Criteria: patients diagnosed with Stage 1-3 trigger finger (Froimson Classification) A1 pulley triggering Exclusion Criteria: trigger thumb multiple trigger fingers on one hand neurological disorders rheumatologic diseases pregnancy patients who had received a steroid injection in the affected finger within the previous six months patients who had previously undergone trigger release surgery