Digital mucous cysts of the finger without osteoarthritis: optimizing outcome of long needle trajectory aspiration and injection.

Digital mucous cysts are common, benign and highly recurrent tumors of the distal interphalangeal joints of the fingers and often associated with osteoarthritis. Multiple treatment modalities have been described, but still no consensus is stated. In the absence of degenerative changes, we promote a novel non-surgical approach. The aim of this study was to examine all patients with digital mucous cysts without underlying osteoarthritis, undergoing this injection technique and to assess outcome and complications of this procedure. This was a single center study (2018-2019) of 17 patients who received a long needle trajectory aspiration and injection for treatment of digital mucous cysts. Exclusion criteria were prior surgical treatment, post-traumatic cyst formation and the presence of radiographic distal interphalangeal joint osteophytosis. A total of 15 patients were found eligible for inclusion. The patient reports were retrospectively analyzed with a follow-up of 6 months. The primary study outcome was resolution of the cyst; secondary outcomes were complications of the procedure. Twelve (80%) resolved completely and three (20%) had limited local recurrence at 6 months. No complications were reported. None of the patients with limited recurrence desired further treatment. We believe that this technique offers a non-invasive, low-cost treatment option for digital mucous cysts, particularly in the subset of patients with ample evidence of degenerative articular changes in the distal interphalangeal joint. The described technique can be performed in an office-based setting and avoids typical surgical as well as aspiration-associated complications.