Fig. 1.

Conceptual model: flare-up symptoms. Subdomains and concepts in italics were reported by only one participant. ^aSome participants also used the word inflammation to refer the tightness or pressure they associate with swelling; swelling is also associated with joint stiffness, which contributes to the loss of function even in the absence of a flare-up leading to new heterotopic ossification. ^bPins and needles, tingling, tenderness, and numbness were used by some participants as additional descriptors for mild pain and mild nerve pain