Adhesions as a component of the trigger finger: a dynamic sonographic study

We performed a detailed dynamic high-resolution ultrasound examination of the flexor tendons in trigger fingers and compared this with normal contralateral digits. There was a loss of defined linear tendon margins and/or traction of the flexor tendons on the surrounding soft tissue during passive flexion of the distal interphalangeal joint in 17 out of 20 trigger fingers, which indicated adherence to the surrounding tissues. The differential motion between the flexor digitorum profundus tendon and the flexor digitorum superficialis tendons was also lost in ten trigger fingers, which suggested adherence between the tendons. No signs of peritendinous or intertendinous adhesions were found in the healthy control fingers. We conclude that tendon adhesions are present in the majority of trigger fingers. We could not determine a relationship between the severity of triggering and the presence of adherence due to limited sample size. Level of evidence: II

Infiltration of synovitis into the flexor tendon: a case report

Synovitis is a type of aseptic inflammation that occurs within joints or surrounding tendons. No previous reports have described a hypertrophic synovium eroding the tendon sheath and manifesting as synovitis within the flexor tendon. We herein report a case involving a 10-year-old girl who presented to our hospital with a 1-month history of a swollen mass and progressive inability to completely flex her left index finger. The active flexion angle of the proximal interphalangeal joint was limited to 85°. A longitudinal incision of the flexor digitorum profundus tendon was surgically performed. The synovium inside and outside the flexor digitorum profundus tendon was completely removed. After the surgical excision, normal tendon gliding returned without recurrence by the 1-year follow-up. The active flexion angle of the proximal interphalangeal joint improved to 100°. To the best of our knowledge, this is the first case of synovitis affecting the flexor tendon and leading to limited flexion of a finger. The manifestation of a double ring sign on magnetic resonance imaging is quite characteristic. Early diagnosis and monitoring of the hyperproliferation and invasiveness of the synovial tissue are required. Surgical excision can be a simple and effective tool when necessary.

Flexor digitorum profundus with or without flexor digitorum superficialis tendon repair in acute Zone 2B injuries

A total of 53 patients with complete cuts of two flexor tendons in Zone 2B treated over a 9-year period was reviewed. Twenty-three patients (28 fingers) had only flexor digitorum profundus repair, while 30 patients (36 fingers) had both flexor digitorum profundus and flexor digitorum superficialis repairs, with a mean follow-up of 21 months (range 12–84). The decision to repair the flexor digitorum superficialis was made according to intraoperative judgement of ease of repair and gliding of the flexor digitorum profundus tendon. Two groups of patients showed no significant differences in total range of active or passive digital motion and power grip percentage to the contralateral hand. However, the values of power grip were statistically superior in the patients with both tendons repaired. The patients after flexor digitorum profundus-only repairs showed significantly greater but still mild flexion contracture (mean 20 °) of the operated digits. The Tang gradings were the same with 89% good and excellent rates in both groups. The conclusion is that although repair of both flexor digitorum profundus and flexor digitorum superficialis tendons is slightly more preferable based on increased grip strength, the repair of the flexor digitorum superficialis together with flexor digitorum profundus is not mandatory. Whether or not to repair flexor digitorum superficialis is an intraoperative decision based on the ease of gliding of the repaired tendon(s). Level of evidence: III