Achilles tendon disorders

It is important to remember that insertional  AT may be inflammatory (enthesitis) and is a key clinical and pathological feature of the spondyloarthropathies which include ankylosing spondylitis, psoriatic arthritis and reactive arthritis - all conditions which can affect  fit active individuals. Confusion can arise between non- inflammatory and inflammatory AT as injury, through running or otherwise,  can trigger onset of peripheral features of the spondyloarthropathies such as enthesitis.

Clues to an underlying inflammatory spondyloarthropathy include associated features such as morning spinal stiffness, psoriasis, joint synovitis or uveitis. Preceding urethral discharge or diarrhoea may suggest a reactive arthritis. However occasionally chronic insertional AT may be the only clinical manifestation when  radiology revealing broad-based fluffy calcaneal  spurs and the presence of HLA B27 gene are helpful pointers to the presence of an underlying spondyloarthropathy. It is important to make the distinction between  non-inflammatory insertional and inflammatory insertional AT as the management of the latter is very different with a clear role for  systemic medications including biologics such as anti-tumour necrosis factor antagonists.