Paolo Queirazza

Unicompartmental knee arthroplasty (UKA) is an effective treatment for anteromedial osteoarthritis in carefully selected patients. Increasing attention has recently been directed toward restoration of pre-arthritic coronal alignment, supported by the use of the arithmetic hip–knee–ankle angle (aHKA) to estimate constitutional lower limb alignment. In medial UKA, kinematic alignment principles derived from the original technique described by Cartier et al. may help to reproduce native joint-line orientation while preserving physiological soft-tissue balance. This technical note details the indications, preoperative assessment, planning strategy, and operative steps of the procedure. Preoperative long-leg weight-bearing radiographs are used to estimate constitutional alignment through the aHKA and to plan the coronal inclination of the tibial cut. Intraoperatively, the distal position of the extramedullary guide is reproduced according to the preoperative planning in order to restore the native inclination of the medial tibial plateau. The sagittal tibial cut, posterior tibial slope, distal femoral cut, component sizing, gap assessment, and cementation technique are described, with emphasis on anatomical landmarks and technical pearls to improve reproducibility. The described technique provides a practical method for approximating constitutional coronal alignment in medial UKA without the use of robotic or navigated systems. The key feature of the procedure is accurate planning and execution of the tibial cut in both the coronal and sagittal planes in order to reproduce native joint-line orientation and preserve appropriate ligament balance.

Objective: To systematically synthesize clinical, structural, biomarker, and safety outcomes of knee joint distraction (KJD) and implantable medial compartment shock absorbers (ISA) for tibiofemoral knee osteoarthritis (KOA), and to summarize comparative evidence versus arthroplasty, high tibial osteotomy (HTO), orthoses, and non-operative care. Design: A PRISMA-based systematic review of PubMed, EMBASE, Scopus, and Cochrane Library from inception to 1 October 2025 identified peer-reviewed clinical studies of KJD or ISA for tibiofemoral KOA. Two reviewers independently screened records, extracted data, and assessed risk of bias. Owing to substantial clinical and methodological heterogeneity and overlapping cohorts, a narrative synthesis was prespecified and no quantitative meta-analysis was performed. Results: Seventeen studies (13 KJD, 4 ISA) reporting on approximately 400 patients met the inclusion criteria. KJD yielded clinically important 1- to 2-year improvements in WOMAC/KOOS and VAS pain, with arthroplasty-free survival of roughly 75% to 85% at 5 to 9 years in selected series, accompanied by increases in radiographic joint-space width and MRI-derived cartilage thickness in the most affected compartment. ISA consistently improved WOMAC pain and function and showed higher 2-year arthroplasty-free survival than HTO or non-operative comparators. Conclusions: Current evidence, based on small heterogeneous cohorts at low-to-moderate certainty, suggests that KJD and ISA can provide meaningful short- to mid-term symptom relief and delay arthroplasty in carefully selected patients. KJD and ISA address different indications and mechanisms and should be considered complementary rather than interchangeable joint-preserving strategies. Larger, independently replicated randomized trials with standardized structural and clinical endpoints are needed before widespread adoption.

Ozone therapy (OT) is used for the treatment of multiple musculoskeletal disorders. In recent years, there has been a growing interest in its use for the treatment of osteoarthritis (OA). The aim of this double-blind randomized controlled trial was to evaluate the efficacy of OT compared with hyaluronic acid (HA) injections for pain relief in patients with knee OA. Patients with knee OA for at least three months were included and randomly assigned to receive three intra-articular injections of ozone or HA (once a week). Patients were assessed at baseline and at 1, 3, and 6 months after the injections for pain, stiffness, and function using the WOMAC LK 3.1, the NRS, and the KOOS questionnaire. Out of 55 patients assessed for eligibility, 52 participants were admitted to the study and randomly assigned into the 2 groups of treatment. During the study, eight patients dropped out. Thus, a total of 44 patients, reached the endpoint of the study at 6 months. Both Group A and B consisted of 22 patients. At 1-month follow-up after injections, both treatment groups improved statistically significantly from baseline in all outcomes measured. At 3 months, improvements remained similarly consistent for Group A and Group B. At 6-month follow-up, the outcomes were comparable between the 2 groups, showing only a worsening trend in pain. No significant differences were found between the two groups in pain scores. Both therapies have proven to be safe, with the few recorded adverse events being mild and self-limiting. OT has demonstrated similar results to HA injections, proving to be a safe approach with significant effects on pain control in patients affected by knee OA. Due to its anti-inflammatory and analgesic effects, ozone might be considered as a potential treatment for OA.