Beyond Mirels: Factors Influencing Surgical Outcome of Metastasis to the Extremities in the Modern Era

Mirels scoring system for determining prophylactic stabilization need of skeletal metastases includes
a limited number of variables and does not differentiate between procedure types. This study sought
to identify additional variables associated with surgical failure, radiographic disease progression, and
patient survival. A retrospective review was performed of patients from January 2004 to 2014 who
underwent surgical treatment of skeletal metastases of the extremities, were >18 years of age, and had
adequate radiographic surveillance. Eighty-nine metastatic bone lesions in 77 patients were included. Mirels score >8 (p = .015) and tumor origin (p = .008) were associated with surgical failure, which was 16.8%. Male gender (p < .001) and use of bone cement (p = .019) were associated with radiographic progression, 43.8% overall. Antiresorptive medications usage (p = .02) was associated with survival. The study concluded that tumor origin may be highly important when considering surgical treatment for metastatic bone disease and antiresorptive medications should be used postoperatively, given an association with survival. (Journal of Surgical Orthopaedic Advances 27(3):178–186, 2018) Key words: complications, extremity metastasis, metastatic disease, Mirels criteria, patient survival, surgery