Two cases are presented of patients with a history of metastatic rectal adenocarcinoma presenting with a painful joint effusion. Both cases are potential examples of metastasis to periarticular bone with local infiltration to the synovium, which is one proposed mechanism of intrasynovial metastasis. While skeletal metastases are a relatively common occurrence in metastatic adenocarcinoma, intraarticular metastasis is extremely rare. These cases highlight the need to consider metastasis in the differential of joint swelling in the setting of a history of adenocarcinoma.