Amyloid is formed by a variety of different proteins which adopt a B-pleated sheet structure. The authors in this study examined the flexor sheaths of forty-seven patients diagnosed with idiopathic trigger finger. Eleven flexor sheath specimens from eleven patients contained localized amyloid deposits with P component glycoprotein. These patients were all over forty- one years of age. Flexor sheath specimens were also obtained from three elderly individuals without trigger finger symptomatology. Two of these samples were similarly found to have localized amyloid deposits with P component glycoprotein. The authors conclude that localized amyloid deposits in the flexor tendon sheath are common with aging and therefore unlikely to contribute to the development of idiopathic trigger finger.
The pathophysiology of primary, idiopathic trigger finger is poorly understood. Trauma and mechanical events have been hypothesized as causative factors but these theories have never been definitively proven. Simple incision of the A-1 pulley is an effective treatment for primary triggering if conservative treatment measures fail. A better understanding of the pathophysiology of this condition may provide further insight into preventative and nonoperative treatment modalities.