Table 1 Case vignette of a typical patient with symptomatic first MTP joint OA

A 63 year-old woman was referred from her general practitioner due to left foot pain, which began insidiously 3 years ago and has steadily worsened over time. Her general practitioner diagnosed her as having first metatarsophalangeal (MTP) joint OA. She is very anxious about the possibility of having foot surgery, feels that her pain is just going to get worse and believes there is nothing she can do to prevent this. She has not had any previous treatment for her foot pain and her health is generally good, although she is overweight, and is on daily medication for hypertension. She is a retired receptionist, lives with her husband and babysits her 4 year-old grandson 2 days per week while her daughter works.

Today she rates the intensity of her foot pain as 6 out of 10. Pain is aggravated by twisting and turning, walking on uneven surfaces and wearing shoes with heels or narrow footwear. She is limited in her ability to perform her daily home duties, and can only vacuum for around 10 min before she has to stop. She finds some relief from applying heat, and takes over-the-counter Paracetamol when she needs it, which is around twice per week. Her big toe joint feels stiff first thing in the morning, which eases after approximately 20 min.

On examination she has a moderately large and somewhat painful bony exostosis on the dorsal aspect of her left first MTP joint. She does not have a medial exostosis (i.e. bunion). Her first MTP joint range of motion is 35° and it has a hard end feel with some crepitus. She has a moderately pronated foot posture and during gait she exhibits excessive midfoot pronation after heel contact, with minimal resupination during propulsion. She also has reduced left first MTP joint motion during the stance phase of gait accompanied by an early heel rise and excessive knee flexion. No other examination findings are remarkable.