Abstract
OBJECTIVE: To evaluate the clinical efficacy and safety of micro-needle knife (MNK) therapy combined with intra-articular and subchondral platelet-rich plasma (PRP) injection compared to intra-articular PRP injection alone in patients with moderate to advanced knee osteoarthritis (KOA). METHODS: This retrospective study enrolled 150 patients (≥ 45 years) diagnosed with moderate to advanced KOA treated at three centers (Tonglu County Traditional Chinese Medicine Hospital, Tonglu County Second People's Hospital, and Zhangshi Traditional Chinese Medicine Hospital) between April 1, 2021, and March 31, 2024. Patients were assigned to either the simple injection group (intra-articular PRP only; n = 135) or the combined treatment group (MNK plus intra-articular and subchondral PRP; n = 106). Clinical outcomes assessed at baseline and after one year included pain (visual analog scale [VAS]), function (Lysholm and WOMAC scores), inflammatory and oxidative stress markers (IL-1β, TNF-α, SOD, MDA), overall clinical efficacy, incidence of adverse events, and structural changes assessed by radiography and Whole-Organ Magnetic Resonance Imaging Score (WORMS). RESULTS: Baseline demographic and clinical characteristics were comparable between groups. One year after treatment, the combined treatment group exhibited significantly lower VAS and WOMAC scores and higher Lysholm scores than the simple injection group (P < 0.05 for all), indicating superior pain relief and functional improvement. Inflammatory and oxidative stress markers showed a more pronounced improvement in the combined group (P < 0.05). Overall efficacy and improvement rates were significantly higher in the combined group (P < 0.05), where cure rates and adverse event rates were similar. No significant differences were observed between groups in knee joint space width or WORMS at baseline or follow-up. CONCLUSION: MNK combined with intra-articular and subchondral PRP injection provides a greater clinical benefit in pain relief, functional recovery, and improvement of inflammatory and oxidative stress markers in moderate to advanced KOA, without increasing adverse events or altering structural outcome compared with intra-articular PRP alone.