Juan José García-Vera

Background Computer-assisted navigation in total knee arthroplasty (TKA) was developed to enhance implant positioning accuracy and optimize mechanical alignment. However, its impact on clinical outcomes remains controversial. This study aimed to evaluate the influence of navigation on functional and radiological outcomes, safety, and patient-reported quality of life at mid-term follow-up. Methods We conducted a retrospective single-center study including 190 patients who underwent primary TKA between 2015 and 2018, with a mean follow-up of 5.8 years. Ninety-five patients were operated on using optical computer navigation, while 95 underwent conventional instrumentation (sequential allocation). All surgeries were performed by the same two senior surgeons using mechanical alignment in both groups. Outcomes included the Hospital for Special Surgery (HSS) knee score, EQ-5D, SF-12, patient satisfaction, and radiographic alignment. Both univariate and multivariate analyses were performed using SPSS (v28.0/v29.0). Results Patients in the navigated group achieved significantly greater improvement in HSS knee scores (mean increase 41.9 vs. 34.9 points; p = 0.043) and a higher proportion of clinically meaningful functional improvement (> 35-point HSS increase: 63.2% vs. 40.0%; p = 0.019) compared to the conventional group. Postoperative knee flexion was also better in the navigated group (118° vs. 113°; p = 0.048). No significant differences were observed in pain improvement (VAS), EQ-5D quality-of-life gain, or complication rates between groups. Navigation significantly reduced the number of outliers in component alignment (6.3% vs. 13.7% outside ± 3° from neutral), although this did not reach statistical significance (p = 0.068). On multivariate analysis, use of navigation was an independent predictor of superior functional improvement (odds ratio 2.65, 95% CI 1.38–5.12; p = 0.003), whereas other factors (age, sex, body mass index, diabetes, baseline HSS) were not significant. Conclusions Computer-assisted navigation in TKA was associated with greater mid-term functional improvement and improved prosthetic alignment, without increasing operative time or complications. Its implementation may be especially beneficial for enhancing stability and precision in mechanically aligned TKA. These findings should be interpreted with caution due to the retrospective design and mid-term follow-up duration. Level of evidence Level III (retrospective comparative study).

Given the wide difference in price per vial between various presentations of hyaluronic acid, this study seeks to compare the effectiveness and treatment cost of stabilized hyaluronic acid (NASHA) in a single injection with standard preparations of hyaluronic acid (HA) in five injections in osteoarthritis (OA) of the knee. Fifty-four patients with knee osteoarthritis (Kellgren–Lawrence Grade II and III) and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain score greater than 7, with a homogeneous distribution of age, sex, BMI, and duration of disease, were included in this study. Patients were randomized into two groups: Group I was treated with NASHA (Durolane^®) and Group II with HA (Go-ON^®). Patient’s evolution was followed up at the 1st, 2nd, 4th, 8th, 12th, and 26th week after treatment. A statistically significant improvement in WOMAC score was observed for patients treated with NASHA versus those who received HA at Week 26. In addition, the need for analgesia was significantly reduced at Week 26 in the NASHA-treated group. Finally, the economic analysis showed an increased cost of overall treatment with HA injections. Our data support the use of the NASHA class of products in the treatment of knee OA.