Retrograde synovial biopsy of the knee joint using a novel biopsy forceps

Abstract

Synovial biopsies of the knee joint are commonly performed arthroscopically with the patient under full or regional anesthesia. To overcome the effort, costs, and potential risks of surgery, we developed an office-based technique for retrograde synovial biopsy using a designated novel biopsy forceps. Using this technique, no arthroscopic or radiologic control is needed to perform rapid synovial biopsies of the knee joint. Concomitant aspiration of synovial fluid can be performed. A technical description of the procedure is given.

Fig 1

Retrograde biopsy forceps. (A) The forceps consist of a grip, a shaft with a suction port, and a blunt tip with a jaw. (B) The blunt tip (asterisk) contains a reverse jaw (plus sign) with the teeth facing the synovial membrane. A small bore (arrow) is used for aspiration.

Fig 2

Course of synovial biopsy. A small skin incision is performed at the insertion site. The forceps is forwarded until the resistance of the capsule is felt. (A) The blunt tip of the forceps penetrates the capsule and (B) is inserted into the suprapatellar pouch while under continuous aspiration. (C) The jaw is opened and now faces the synovial membrane. (D) The forceps is pulled back until the open jaw is fixed on the synovial membrane. (E) Closing the jaw acquires the synovial biopsy specimen.