Hip Joint Disease in Psoriatic Arthritis: Risk Factors and Natural History

Overview

This document discusses the study on hip joint disease in patients with psoriatic arthritis (PsA), focusing on risk factors and the natural progression of the disease.
Study conducted by C. Michet, T. Mason, and M. Mazlumzadeh from the Division of Rheumatology at Mayo Clinic.

Sample Size: 504 patients diagnosed with PsA according to ESSG criteria.
Follow-Up Duration: Mean follow-up period was 5.7 years.
Age of Onset: Mean age at onset of psoriasis was 32 years; mean age at onset of PsA was 39 years.
Patterns of PsA:
- Oligoarticular pattern was most common at onset (49%).
- Polyarticular pattern was most common at latest examination (65%).
- Sacroiliitis or spondylitis diagnosed in 94 patients (18.7%).

Development of Hip Arthropathy:
- 32 patients (6.3%) developed psoriatic hip arthropathy.
- 26 of these 32 patients (81%) also had sacroiliitis or spondylitis.
- In 41% of these cases, the hip joint became affected within 1 year of PsA onset.
- Younger patients more commonly developed hip disease.
- Sex, arthritis pattern, psoriasis duration, and other factors like dactylitis or enthesitis were not linked to increased hip disease risk.
Progression and Treatment:
- 17 patients were followed up, and 9 required hip arthroplasty.
- 50% of these patients underwent arthroplasty within 5 years of onset of hip pain.

Psoriatic hip arthropathy is relatively rare in PsA.
It is associated with earlier arthritis onset and linked with psoriatic spondylitis.
Bilateral hip involvement and rapid progression to hip arthroplasty are common observations.

The full text of the study is available as a PDF.
A case illustrating established hip arthropathy in a patient with a history of psoriasis and PsA is included in the study.
This study is published in the Annals of the Rheumatic Diseases, courtesy of BMJ Publishing Group.