Tranexamic Acid (TA) has been shown to reduce transfusion rates in Total Knee Replacement (TKR) without complication. In our unit it was added to our routine enhanced recovery protocol. No other changes were made to the protocol at this time and as such we sought to examine the effects of TA on wound complication and transfusion rate. All patients undergoing primary TKR over a 12 month period were identified. Notes and online records were reviewed to collate demographics, length of stay, use of TA, thromboprophylaxis, blood transfusion, wound complications and haemoglobin levels. All patients received a Columbus navigated TKR with a tourniquet. Only patients who received 14 days of Dalteparin for thromboprophylaxis were included. 124 patients were included, 72 receiving TA and 52 not. Mean age was 70. Four patients required a blood transfusion all of whom did not receive TA (p = 0.029). Mean change in Hb was 22 without TA and 21 with (p = 0.859). Mean length of stay was 6.83 days without Tranexamic Acid and 5.15 with (p < 0.001). 15% of patients (n=11) of the TA group had a wound complication, with 40% of patients (n=21) in the non TA group (p = 0.003). There was one ultrasound confirmed DVT (non TA group). No patients were diagnosed with pulmonary embolus. In our unit we have demonstrated a significantly lower transfusion rate, wound complication rate and length of stay, without any significant increase in thromboembolic disease with the use of TA in TKR

Background. Computer-assisted navigation systems for total knee arthroplasty (TKA) were introduced to improve implantation accuracy and to optimize ligament balancing. Several comparative studies in the literature confirmed an effect on the component position and other studies could not confirm these results. For ligament balancing most studies found no significant influence on the clinical outcome using a navigation system for TKA. In the literature there were no reports of mid-term results after navigated TKA. With our study we wanted to show if the use of a navigation system for TKA will have an influence on the component's position and on the clinical results at 5-year follow up. Methods. We enrolled 200 patients in a prospective randomized study with a minimum follow up of 5 years. 100 TKA were operated on without using a navigation system (Group A) and 100 surgeries (Group B) were done with computer assistance. Radiological investigation by standard radiographs including a long-leg X-ray was performed with a follow up rate in Group A of 86.2% versus 80.2% in Group B. We measured the mechanical axis of the leg, lateral distal femoral angel (LDFA), medial proximal tibial angle (MPTA), tibial slope and the alpha-angle of the patella. Clinical investigation was performed with a follow up rate in Group A of 85.7% versus 79.8% in Group B including the parameters for the range of motion (ROM), ligament balancing, anterior drawer test, feeling of instability, anterior knee pain, effusion, WOMAC Score, Insall Score and HSS Knee Score. Results. In both groups there was no aseptic loosening or difference in TKA survival rate (Group A 95.4% versus Group B 98.85% 5-year survival rate, p = 0.368). With the navigation technique the mechanical axis of the limb in the frontal plane was improved (p = 0.015; Group B: 1.67 ° ± 1.6° versus 2,44 ° ± 2.2 ° in Group A). 90% of the Group B and 81% of the Group A were within 3 ° varus/valgus deformity of the mechanical axis of the limb (p = 0.157). The accuracy of tibial slope was higher in the Group B (p = 0.001). More patients of the Group B (95% versus 79%) were within a deviation of 3 °, −7 ° tibial slope (p = 0.007). The mean deviation of 90 ° LDFA was higher (p = 0.034) in the Group A (1.89 ° versus 1.36 ° in Group B). Mean deviation of 90 ° MPTA, mean MPTA, mean LDFA and patella alpha angle were similar in both groups (p 0.253). There was no difference in ROM, ligament balancing, anterior drawer test, anterior knee pain or feeling of instability (p 0.058). Insall Knee Score total (181 Group A/191 Group B) and HSS Knee Score total (91 Group A/93 Group B) was higher with the navigated procedure in Group B (p 0.026). WOMAC total and HSS grades were similar in both groups (p 0.070). Conclusions. The accuracy of the mechanical axis of the limb and the tibial slope was higher with the navigated procedure. TKA survival rate and clinical outcomes were similar in both groups at 5-year follow up

Electromagnetic navigation versus conventional Total Knee Arthroplasty: Clinical improvements Optical and electromagnetic (EM) tracking systems are widely used commercially. However in orthopaedic applications optical systems dominate the market. Optical systems suffer from deficiencies due to line of sight. EM trackers are smaller but are affected by metal. The accuracy of the two tracker systems has been seen to be comparable1. Recent advancements in optical navigated TKA have shown improved overall limb alignment, implant placement and reduce outliers when compared to conventional TKA2-4. This study is the first RCT to compare EM and conventional TKA. Two groups of 100 patients underwent TKA using either the EM navigation system or the conventional method. Frontal, sagittal and rotational alignment was analysed from a CT scan. Clinical scores including Oxford Knee Score (OKS) and Knee/Function American Knee Society Score (AKSS) were recorded pre-op, and at 3 and 12 months post-op. 3 month data presented includes 180 patients (n = 90). The 12 months data presented includes 140 (n = 70). The two groups had similar mean mechanical axis alignments (EM 0.31o valgus, conventional 0.15o valgus). The mechanical axis alignment was improved in the EM group with 92% within +/-3o of neutral compared to 84% of the conventional group (p = 0.90). The alignment of the EM group was improved in terms of frontal femoral, frontal tibial, sagittal femoral, sagittal tibial and tibial rotation alignment. However, only the sagittal femoral alignment was significantly improved in the EM group (p = 0.04). Clinically, both TKA groups showed significant improvements in OKS and AKSS scores between both pre-op to 3 month post-op and 3 months to 12 months post-op (p<0.001). The OKS and the AKSS knee score for the EM group was significantly better at 3 months post-op (OXS p = 0.02, AKSS knee p = 0.04). However there was no difference between the groups at 12 months. The mean pre-op range of motion (ROM) for both groups was 105o. This decreased to 102o in the EM group and 99o in the conventional group at 3 months. There was a significant improvement at 12 months post-op, EM = 113o (p = 0.012) and conventional = 112o (p = 0.026). There was no significant difference in ROM between the two groups at 3 or 12 months post-op. Therefore the alignment outcome of the EM TKA group was improved compared to the conventional group. The EM group also showed clinical improvements at 3 months post-op however these were not seen again at 12 months post-op. ROM was seen to decrease at 3 months post-op but then significantly improve by 12 month post-op