Impact of postoperative femorotibial axis on functional outcomes in unicompartmental knee arthroplasty.

OBJECTIVES: This study aimed to compare the functional outcomes of patients undergoing fixed-bearing medial unicompartmental knee arthroplasty (UKA) classified as either varus or neutral based on their postoperative femorotibial angle (FTA), with the goal of evaluating the impact of FTA on functional results. PATIENTS AND METHODS: A total of 38 knees of 35 patients (27 females, 8 males; mean age: 63.6±7.1 years; range, 52 to 75 years) were included in this retrospective study. The data was collected between December 15, 2020, and January 15, 2021. Patients were categorized into two groups based on their postoperative FTA. The neutral group consisted of patients with an FTA range of 5.1° to 7.4°, while the varus group included patients with an FTA range of 0.1° to 4.8°. Knee Outcome Osteoarthritis Score (KOOS), Visual Analog Scale (VAS) scores, sit to stand test results, and six minute walk test data were analyzed. RESULTS: The mean follow-up was 42.0±19.3 months. The postoperative VAS score for the varus group was 0.95±0.99, whereas the neutral group had a VAS score of 2.19±1.83 (p=0.021). The mean KOOS for the varus group was 88.01±7.88, whereas the neutral group had a mean KOOS score of 78.46±13.69 (p=0.006). CONCLUSION: In patients undergoing UKA, mild varus alignment could yield superior early and midterm functional outcomes compared to a neutral femorotibial angle.

Radiological Evaluation of Distal Tibiofibular Joint Anatomy Variations in Patients with and Without Syndesmotic Injury.

Introduction: Syndesmosis injuries are a common and debilitating problem affecting the ankle joint, but the precise causes of these injuries remain unclear. In the current retrospective study, it was aimed to investigate the relationship between variations in the distal tibiofibular syndesmosis and surgically proven syndesmosis injuries. Patients and Method: A total of 57 patients with surgically proven syndesmosis injuries and 51 patients without syndesmosis injuries were included as the control group. Computed tomography (CT) scans were used to measure six anatomical features 1 cm proximal to the tibiotalar joint, including the anterior facet length (a), posterior facet length (b), angle between the anterior and posterior facets (c), fibular incisura depth (d), tibia thickness (e), and fibula thickness (f). Results: Comparing the measurements of the patients with and without syndesmosis injury, it was demonstrated that the anterior facet length (a) (p = 0.022) was shorter and the a-b difference (anterior facet length-posterior facet length difference) (p = 0.010) tended toward negative values. Pearson correlation analysis demonstrated that a (r = - 0.211, p < 0.033) and a-b (r = - 0.254, p = 0.010) measurements were strongly negatively correlated with syndesmosis injury. Discussion: Our study findings suggest that the shortness of the anterior facet and the difference in length are related to syndesmosis injuries. To the best of our knowledge, this is the first study to report this relationship with syndesmosis. This study sheds light on the underlying mechanisms of syndesmosis injury, which could help clinicians in the diagnosis, treatment, and prevention of this common ankle injury.Level of evidence: Level 4: case-control study.

Radiologic Evaluation of the Effect of Distal Tibiofibular Joint Anatomy on Arthroscopically Proven Ankle Instability.

BACKGROUND: Ankle sprains occur frequently in both athletes and the general population. The social and economic consequences can be significant. In an effort to understand the injury, dynamic and static structures around the ankle have been investigated in detail, but anatomical factors predisposing to lateral ankle instability have not been fully clarified. The aim of this study was to radiologically investigate the relationship between bony variations of the distal tibiofibular joint and arthroscopically proven ankle instability. METHODS: Fifty patients with arthroscopically proven ankle instability and 50 patients without instability were included in this study. Measurements were obtained from a magnetic resonance imaging (MRI) section 1 cm proximal to the tibiotalar joint; distal tibiofibular joint anterior facet length (a), posterior facet length (b), angle between the anterior and posterior facets (c), fibular notch depth (d), tibia thickness (e), and fibula thickness (f) was measured. RESULTS: It was found that instability was more frequent when the length of a (P < .001) and e (P < .001) were shorter. In addition, when value of a/b and e/f were evaluated, it was observed that the number of individuals who had instability increased as the ratio became smaller (P < .016-.020, respectively). Pearson correlation analysis indicated strong negative correlation between the values of a-e and instability (r = -0.348, P < .001, and r = -0.328, P = .001; respectively). CONCLUSION: Lateral ankle sprains are common, and a clear understanding of the relevant structures and clinical function of the ankle complex should extend beyond the talocrural joint. This study demonstrated that the presence of narrow anterior facet (a) and thinner tibia (e) were strongly correlated with lateral ankle instability. LEVEL OF EVIDENCE: Level III, retrospective case control study.