Treatment of Early Undifferentiated Chronic Monoarthritis of the Wrist by Arthroscopic Wrist Synovectomy Combined with Partial Denervation

Abstract

Objective: Undifferentiated chronic monosecarthritis (UCMA) is a group of inflammatory joint diseases that has the potential to progress to other diseases and can seriously affect patients' quality of life. There is yet no unified consensus regarding treatment of UCMA. This study aimed to investigate the efficacy of arthroscopic synovectomy combined with partial wrist denervation in treating Larsen 1-3 UCMA.

Methods: In this case series, we reviewed 14 patients with UCMA treated by arthroscopic synovectomy combined with partial denervation from February 2017 to June 2020. The mean duration of symptoms was 17.4 months (range, 4-60 months), and the mean follow-up was 13.3 months (range, 6-23 months). The anterior and posterior interosseous nerves were severed at the distal forearm, and the radiocarpal, midcarpal, and distal radial ulnar joint synovial membranes were arthroscopically resected at the wrist. The clinical evaluation indices included the visual analogue scale score (VAS) for pain, grip strength, range of (active) motion of the wrist, total active motion, and Mayo wrist score. Larsen's scoring method was used as the imaging evaluation index.

Results: At the last follow-up, significant clinical improvements were observed in the visual analogue scale (VAS) score for pain (6.0 (5.0-6.3) vs 1.0 (1.0-2.3), P = 0.001) and Mayo wrist score (42.1 ± 9.7 vs 61.8 ± 12.3, P < 0.0001). No significant changes were found in grip strength (15.9 ± 4.5 vs 16.6 ± 4.7, P = 0.230) or the flexion-extension arc (58.9 ± 39.0 vs 64.3 ± 36.5, P = 0.317), although the mean and median did show positive changes. Among the three patients who showed progress in imaging, there was no significant difference in their pain and functional scores compared to those who did not progress. One patient underwent total wrist fusion 17 months after the operation.

Conclusion: Arthroscopic wrist synovectomy combined with partial wrist denervation can provide sustained pain relief and functional recovery for patients with Larsen 1-3 UCMA.

Keywords: Arthritis; Arthroscopy; Denervation; Synovectomy; Undifferentiated.

Fig. 1

Arthroscopic view of the wrist. (A, B) Intraoperative photographs show synovial hyperplasia in the radiocarpal and midcarpal joints. (C) Intraoperative photograph shows a perforation in the triangular fibrocartilage that became visible after clearance of the palmar synovial tissue. The synovium in the distal radial ulnar joint could be cleared through this perforation.

Fig. 2

The procedure of partial wrist denervation. (A) The design of the skin incision. A 3‐ to 4‐cm longitudinal incision was made, extending distally to a point approximately one finger breadth proximal to the head of the ulna, and centered between the radius and the ulna. (B, C) Intraoperative photographs show the posterior interosseous vessels and nerve (marked in Fig. 2B) after retracting the extensor pollicis longus muscle toward the ulna. (D) The posterior and anterior interosseous nerves were excised approximately 1 cm. (E, F) Intraoperative photographs show the anterior interosseous vessels and nerve (marked in Fig. 2E), which could be seen after a 3‐cm longitude incision on the interosseous membrane.

Fig. 3

Case 1, a 53‐year‐old female, presented with right wrist joint swelling and pain 2 years ago, which progressively worsened over time despite pharmacological intervention, necessitating the combined procedure. Postoperatively, at an 8‐month follow‐up, the VAS score of pain improved from 4 to 1, and the grip strength of the affected side increased by 4.8 kg. The Mayo score also improved from 55 to 75. (A, B). Preoperative x‐ray images of the right wrist joint. (C, D) x‐ray images at 2‐year follow‐up after surgery.

Fig. 4

Case 2, a 33‐year‐old male, experienced right wrist pain with a concomitant decrease in range of motion for 5 years and was diagnosed with UCMA. The pharmacological intervention failed to slow disease progression. At a 9‐month follow‐up after surgery, the VAS score of pain improved from 5 to 0, and the Mayo score increased from 55 to 75. (A, B) Preoperative x‐ray images of the right wrist joint. (C, D) X‐ray images at the latest follow‐up (9 months) after surgery.