- Measures joint circumference
- Simple and quick to use
- The only validated tool for assessing dactylitis
- Includes assessment sheet
- Cost effective
The Leeds Dactylometer provides a means to measure psoriatic disease or other similar dermatological and rheumatological factors.
Dactylitis has been defined as “uniform swelling such that the soft tissues between the metacarpophalangeal and proximal interphalangeal, proximal and distal interphalangeal, and/or distal interphalangeal joint and digital tuft are diffusely swollen to the extent that the actual joint swelling could no longer be independently recognised.” Dactylitis is a hallmark clinical feature in patients with spondyloarthropathies (SpA) and is commonly observed in psoriatic arthritis.
Dactylitis occurs in 16-48% of cases of psoriatic arthritis (PsA). Acute dactylitis has been shown to be a clinical indicator of disease severity in PsA; conversely, chronic, non-tender diffuse dactylitic swelling may be less clinically significant. Dactylitis is due to inflammation in the majority of tissues in the digit - the tendon sheaths, joints, bones and soft-tissues in between. Recurrent dactylitis, often in the same digit(s), may be the only clinical manifestation of PsA.
The only validated tool for assessing dactylitis is the Leeds Dactylometer. The validity of this instrument has been assessed using the OMERACT filter. The instrument and tool has demonstrated good evidence of responsiveness in clinical trial. In addition, the instrument incorporates a definition of dactylitis (a 10% difference in the ratio of circumference of the affected digit to the contralateral digit). Using the contralateral digit as a normator enables any inter-individual variation in measurement technique to be minimised. The instrument comes with an assessment sheet (see reverse) which provides automatic computation of the Leeds Dactylitis Index.