Can bedside needle arthroscopy of the ankle be an accurate option for intra-articular delivery of injectable agents?

Abstract
Bedside needle arthroscopy of the ankle under local anesthesia has been proposed for intra-articular delivery of injectable agents. Accuracy and tolerability of this approach in the clinical setting–including patients with end-stage ankle pathology and/or a history of prior surgery–is not known. To assess clinical accuracy and tolerability of bedside needle arthroscopy as a delivery system for injectable agents into the tibiotalar joint. This was a prospective study that included adult patients who were scheduled for an injection with hyaluronic acid to the tibiotalar joint. In our center, these injections are used as a last resort prior to extensive surgery. The primary outcome was injection accuracy, which was defined as injecting through the arthroscopic cannula with intra-articular positioning confirmed by a clear arthroscopic view of the joint space. Secondary outcome measures included a patient-reported numeric rating scale (NRS, 0-10) of pain during the procedure and willingness of patients to return for the same procedure. NRS of ankle pain at rest and during walking was collected at baseline and at 2-wk follow-up. Complications were monitored from inclusion up to a 2-wk control visit. We performed 24 inspection-injections. Eleven (46%) participants were male, and mean age was 46.8 ± 14.5 years. Osteoarthritis was the indication for injection in 20 (83%) cases, of which 8 (33%) patients suffered from osteoarthritis Kellgren-Lawrence grade IV, and 10 (42%) patients from Kellgren-Lawrence grade III. An osteochondral defect was the indication for injection in 4 (17%) cases. A history of ankle surgery was present in 14 (58%) participants and a history of multiple ankle surgeries in 11 (46%) participants. It was possible to confirm accuracy in 21 (88%) procedures. The 3 (12%) participants where needle arthroscopy did not reach a clear view of the joint space all suffered from Kellgren-Lawrence grade IV osteoarthritis. Pain during the procedure was reported with a median of 1 [interquartile ranges (IQR): 0–2]. Willingness to return was 100%. Pain in rest decreased from a median NRS of 4 (IQR: 2–7) at baseline to a median of 3 (IQR: 1–5) at follow-up (P < 0.01). Pain during walking decreased from a median NRS of 8 (IQR: 6–9) to a median of 7 (IQR: 4–8) (P < 0.01). Infections or other complications were not encountered. Clinical accuracy and tolerability of bedside needle arthroscopy of the ankle as a delivery system for injectable agents are excellent. Accuracy was 100% in patients without total ventral joint obliteration.