This is not the ranting of a crazy man, it’s a mnemonic. A mnemonic is a catchy phrase whose letters stand for categories that by themselves are hard to remember. I love mnemonics and use them liberally to help me organize the vast amount of data in orthopedics.
They are particularly useful in confusing cases in which the diagnosis is unclear. The above mnemonic, one of my favorites, helps me consider all the diagnostic possibilities.
For example, a 60 year old diabetic woman with multiple medical problems presents to the orthopedist with gradual onset of increasing hip pain. The list of possible causes is endless, ranging from a simple sprain to infection or bone cancer. We’ll use our mnemonic to explore the possibilities, with the underlined capital letters indicating the various categories to be considered: F…T…S…AN.. IDIOTS
Fracture – particularly fragility fractures (see last month’s column)
Tumor – including cancer and benign bone lesions
Sepsis – another word for infection, of bone, joint, or soft tissue, including Lyme
Angio – short for blood clot (“DVT”)
Nerve –from mechanical (ruptured disc pinching a nerve) to medical neuropathies
(diabetes, MS, etc)
Inflammatory – joint (rheumatoid, gout), tendon (“bursitis”), or muscle (polymyalgia
Degenerative – osteoarthritis and tendonopathy
Instability – in this case hip, but it can affect many joints, including spine
Osteonecrosis – or, “death of bone”, a painful condition that can target the hip
Transient – transient osteopenia or synovitis of the hip, both painful, both
Sprains – and strains of muscles, tendons, or ligaments about the hip.
Keeping this mnemonic in mind, we can perform a well focused history and physical, order appropriate imaging, and feel confident we can arrive at the correct diagnosis in challenging cases.