Arthroscopic Lunate Decompression with K-Wire Fixation for Lichtman Stages II–IIIa Kienböck’s Disease: A Retrospective Study

Abstract Background Kienböck’s disease, characterized by lunate avascular necrosis, requires effective interventions to relieve pain and restore function. This study evaluated arthroscopic lunate decompression with K-wire fixation for Lichtman stage II–IIIa patients. Methods A retrospective cohort of 32 patients (18 stage II, 14 stage IIIa) treated at Ningbo No. 6 Hospital (2018–2022) was analyzed, with a 12-month follow-up. The sample size was determined via a power calculation (α = 0.05, power = 0.80) on the basis of VAS score reduction. The primary outcomes were visual analog scale (VAS) pain scores and Mayo wrist scores; the secondary outcomes included grip strength, wrist range of motion (ROM), and the lunate height index. Paired t tests, independent samples t tests, and Cohen’s d effect sizes were used. Results The VAS score decreased to 2.91 ± 0.82 at 3 months and 2.35 ± 0.70 at 6 months, from 7.33 ± 0.95 to 1.73 ± 0.44 at 12 months (mean difference: 5.60, 95% CI: 5.12–6.08, P < 0.001, Cohen's d = 5.89), exceeding the minimal clinically important difference (MCID, 1.5 points). The Mayo wrist score improved from 44.58 ± 8.56 to 86.01 ± 7.85 (mean difference: 41.43, 95% CI: 37.92–44.94, P < 0.001; Cohen's d = 4.85). The grip strength reached 86.17 ± 7.25% of that of the contralateral side. Stage II patients had lower VAS scores (1.57 ± 0.38) than did stage IIIa patients (1.94 ± 0.43, P = 0.017). The complications included transient nerve numbness, pin-site infections (15.6% each), and wrist stiffness (12.5%), all of which were resolved conservatively. Conclusion Arthroscopic lunate decompression with K-wire fixation significantly reduces pain and improves function in patients with stage II–IIIa KD, with superior pain relief in patients with stage II disease. This minimally invasive approach shows promise but requires multicenter randomized controlled trials for long-term validation.