Clinical features of flexor tenosynovitis
Noninfective and infective flexor tenosynovitis may present similarly. People usually present with one or more swollen inflamed digits and impaired hand function. There is associated pain, erythema and stiffness in the affected digit(s), often worse in the morning and after prolonged periods of rest.
Small-joint synovitis may be present if the person has a coexisting inflammatory rheumatological condition (eg rheumatoid arthritis, spondyloarthritis, psoriatic arthritis).
Infective flexor tenosynovitis is more likely if the person presents acutely following an injury (especially penetrating injury or bite to the hand) and has systemic features (eg fever). The cardinal signs of infective flexor tenosynovitis (known as Kanavel signsRay, 2022) are:
- tenderness along the course of the flexor sheath
- fusiform enlargement of the affected digit
- digit slightly flexed at rest
- pain along the tendon with passive extension.
Although flexor tenosynovitis usually affects multiple digits, it can (rarely) present in a single digit resembling an infective dactylitis or ‘sausage digit’. Infection must be excluded in anyone presenting with single-digit flexor tenosynovitis or dactylitis.
Flexor tenosynovitis is a clinical diagnosis and while investigations may support a diagnosis, they are not the priority in management.