Percutaneous Release vs Steroid Injection for Trigger Finger

Trigger fingers (TF) is the common cause of pain and disturbed function of hand. Many studies show that percutaneous release of A1 pulley has better outcome than the steroid injection. However, over the past many years, steroid injection has been considered as the choice of treatment after the failure of conservative treatment methods. The aim of this study is to assess the effect of percutaneous release of A1 pulley compared with the local Steroid injection in the treatment of trigger fingers.

This study is based on a randomized clinical trial to compare the effect of the percutaneous release of A1 pulley with steroid injection in trigger fingers. A total of 112 participants aged 18 years and above suffering from trigger fingers with failed conservative treatment will be intervened randomly (56 participants in injection group and 56 participants in percutaneous release group). The Quinnell's classification, VAS scoring system and active range of movement in the affected site will be assessed at the baseline and the same criteria will be at one month and three month as end line assessment. Statistical analyses will be performed using independent t-test and Mann Whitney U test to compare between the two means. The outcome of this study will help to guide the physicians to choose the better therapeutic approach among the patients suffering from trigger fingers.

Stenosing flexor tenosynovitis also known as trigger finger. It is a common clinical condition where there is locking and clicking during flexion and extension of the involved digit or even locking. The trigger ring finger is the first commonest, and the trigger thumb is the second commonest of trigger fingers. Flexor tendon gliding motion is dependent on a 'Critical Tendon Sheath Caliber Tolerance' which allows passage of flexor tendon through the A1 pulley in the Metacarpophalangeal joint.

The prevalence of trigger finger is 2 % in the general population, which is most common in women in the fifth or sixth decade of life. The possibility of a trigger finger is between 2 and 3% during the lifetime, which increases up to 10 % in diabetic patients. The trigger finger in diabetic patients suffered from worse renal function and glycemic control, along with a higher incidence of cardiovascular disease. The causes of Trigger finger are still not well known, some factors may increase the risk of developing the condition such as forceful hand activities (mechanical irritation, congenital and medical conditions (Diabetes and Rheumatoid arthritis). Trigger thumb is caused by thickening of flexor tendon gliding at the tendon A1 pulley interface or thickening of A1 pulley.

Diagnosis is primarily made based on physical examination. The patients often present with pain or clicking at the metacarpal head, which causes difficulty in holding or grasping objects. In most advanced cases, there is locking in flexion or extension position.

Nowadays, the morphological changes in the case of trigger fingers can be ruled out by high-resolution ultrasonography with a high-frequency transducer, and it has been found that the cut-off for pathological findings is a 20% increase in tendon thickness compared to the contralateral tendon. The average width and thickness of the A1 pulley are 7.1 mm and less than 1 mm respectively.

Treatment of Trigger fingers includes conservative such as splinting, oral medications, injection, and surgical management such as open release, and percutaneous release. Steroid injection has been serving us as a traditional way of injection therapy for many years for those who are not getting better with oral medications and physiotherapy. Steroid injection is effective because of its anti-inflammatory properties.

The first percutaneous release was performed in 1958 and the success rate was 100% without any reported complications. Percutaneous A1 pulley release has been the method of choice for patients who does not respond to conservative treatment (local steroid) with low complication rates.

There is a concern regarding percutaneous release in the thumb, where tendon sheath and neurovascular bundle are in proximity.

The technique of local steroid injection into the flexor sheath was described by Howard in 1953. It has become an accepted initial treatment for trigger fingers largely due to its use within the outpatient department and its low complication rate.

Eligibility Criteria:
Inclusion Criteria:

* Participants aged 18 years and above
* Duration of symptoms :≥ 3 months
* Triggering in any of the digits of hand
* Trigger finger type II-IV based on Quinnell classification

Exclusion Criteria:

* There is prior treatment for trigger finger, or Trigger thumb
* There had been previous surgery or other hand pathology such as rheumatoid arthritis, osteoarthritis, Dupuytren's contracture and diabetic mellitus.