Objective:To analyze the clinic effects of arthroscopic partial trapeziectomy and suture button suspensionplasty in the treatment of first carpometacarpal joint (CMCJ) Eaton stage II/III arthrosis.Methods:A retrospective study was conducted on a total of 15 cases (16 hands) of patients including 5 males (1 bilateral) and 10 females with CMCJ stage II/III arthrosis who underwent surgical treatment at the first affiliated hospital of Shenzhen university from January 2020 to June 2022, with mean age of 56.7±6.4 years (range, 46-75 years). The duration from pain to treatment was 7.8±3.2 months (range, 4-14 months). X-ray showed narrowing of CMCJ with osteophytes and distal radial subluxation. All the patients were treated with arthroscopic partial trapeziectomy and suture button suspensionplasty. The preoperative and last postoperative follow-up radiographs, visual analogue scale (VAS), thumb's Kapandji scores, disabilies of the arm, shoulder, and hand (DASH) scores, grip and pinch strength and time to return to work were compared.Results:All cases were followed up for 19.6±6.3 months (range, 11-36 months). The postoperative X-ray showed all the CMCJs were reduced with a normal height of first metacarpal. The mean time for patients to return to their daily activities was 18.69±3.70 d and the mean time to return to work was 24.63±4.91 d. The average VAS score decreased from 6.56±1.15 preoperatively to 1.00 (0.75, 1.25). The preoperative Kapandji's score was 8.00±0.82 and the postoperative Kapandji's score was 8.00 (7.25, 9.00). The average DASH values improved from 24.06±3.19 to 4.00 (3.00, 5.00). The were significant differences except for Kapandji score ( Z=-4.905, P<0.001; Z=-0.121, P=0.905; Z=-4.846, P<0.001). The mean grip and pinch strength showed improvement from an average of 16.4 (14.13, 18.68) kg and 1.70±0.35 kg to 26.14±3.27 kg and 3.58±0.91 kg with significant difference ( Z=-4.617, P<0.001; t=-7.669, P<0.001). Conclusion:Arthroscopic partial trapeziectomy and suture button suspensionplasty is a minimally invasive surgery for the treatment of first CMCJ Eaton stage II/III arthrosis. By this technique, the patients' existing instability and pain problems can be solved.