Caveat arthroscopy: definition and guidelines for prevention.

Caveat arthroscopy is defined as an arthroscopy done with the intention of managing intra-articular nonneoplastic disease that suddenly escalates into the surgical treatment of an extra-articular neoplasm. The term caveat arthroscopy is used to describe a maloccurrence, not an act of negligence. The purpose of this retrospective review is to provide examples of this entity, examine its consequences, and suggest guidelines for prevention. We identified 13 individuals who had caveat arthroscopy over a 6-year period. All but one case involved the knee. Diagnoses included 5 soft tissue sarcomas, 5 benign bone tumors, 2 skeletal sarcomas, and 1 benign soft tissue tumor. In each case, there were complications related to prereferral biopsy (ie, biopsy done before definitive management at a tertiary institution). Every subject had at least one untoward event consisting of either compartment contamination, inaccurate diagnosis, or delay in diagnosis. The best way to avoid the complications of caveat arthroscopy is to avoid the tendency to biopsy extra-articular lesions. Instead, adequate imaging of a suspected neoplasm should be done, and referral before biopsy should be considered.