Arthritis in the knee is a leading cause of pain and disability with total knee arthroplasty (TKA) often the treatment of choice after failure of more conservative treatments. TKA has been demonstrated to be one of the most successful procedures performed.  However, despite the good long-term survivorship rates, patient satisfaction is still an issue post TKA with over 20% of patients exhibiting patient dissatisfaction most commonly due to anterior knee pain (over 18-28% patients) and mediolateral or varus-valgus instability.  Recent studies have demonstrated that collateral ligament strains are altered post TKA which may lead to laxity and/or tightness of the ligaments resulting in patient discomfort, pain, stiffness and/or instability post TKA.  As a result, it may be beneficial to ensure ligamentous strains after TKA are similar or close to the native situation.  The purpose of this study was to evaluate the clinical and radiographic results of the Unity Knee™ Total Knee System (Corin Ltd, Cirencester, UK), a modern generation, single-radius total knee replacement (TKR) and its accompanying instrumentation which is designed to help maintain proper ligament balance and restore the medial jointline.  A total of 89 knees (89 patients) were implanted with the device in a single surgeon series.  All patients were assessed using the American Knee Society Score (AKSS), the Oxford Knee Score (OKS), and radiographs.  There was 1 revision due to infection and Kaplan-Meier survivorship was 98.9% at 2 years.  The mean AKSS knee score for the total cohort was 87.1 ± 7.98 and the mean Oxford Knee score was 45.89 + 3.69. Radiographic review found no signs of radiographic failure in any of the knees. This study demonstrates good survivorship, clinical, and radiographic results at 2 years for this TKR.

Objectives: Applying the correct amount of collateral ligaments tension in the knees during surgery is a prerequisite to restore normal kinematics after TKA. It is well known that a low value of ligament tension could lead to an instable joint while a higher tension could induce over-tensioning and problems at later follow-up. In this study, an experimental cadaveric activity was performed to measure the minimum tension required to achieve stability in the knee joint.Methods: 10 cadaveric knee specimens were investigated in this study. The femur and tibia were fixed with polyurethane foam in specific designed fixtures and clamped to a loading frame.Increasing displacement was applied to the femoral clamp and the relative force was measured by a loading-frame machine up to the stability of the joint, determined by a decrease in the derivate of the force/displacement trend followed by a plateau.The force span between the slack region and the plateau was considered as the tension required to stabilize the joint.This methodology was applied for joints with intact cruciate ligaments, after ACL resection and after further PCL resection, to simulate the knee behavior prior a CR and a PS implant.The test was performed at 0, 30, 60 and 90° of flexion. Each configuration was analyzed three times for the sake of repeatability.Results and Conclusion: Results demonstrated that an overall tension of 41.2N (range 30.0-48.0 N) is sufficient to reach stability in a native knee with intact cruciate ligaments. Similar values appear to be sufficient also in an ACL resected knee (average 45.6, range 41.2-50.0 N), while higher tension is required (average 58.6N, range 40.0-77.0 N) were necessary in the case of PCL retention. Moreover, in this configuration, the tension required for stabilization was slighter higher at 30 and 60° of flexion compared to the one required at 0 and 90° of flexion.The results are in agreement to the ones found by other recent experimental study [Manning et al 2018 (KSSTA)] and shown that the tension necessary to stabilize a knee joint in different ligament conditions is way lower than the ones usually applied via tensioners nowadays.To reach functional stability, surgeons need to consider such results intraoperatively to avoid laxity, mid-flexion instability or ligament over-tension.

IntroductionApplying proper tension to ligaments during Total-Knee-Arthroplasty surgery is fundamental for optimal implant performance: low tensions lead to joint instability, over-tensioning to pain and stiffness. "Functional stability" must then be defined and achieved. An experimental cadaveric activity was performed to measure the minimum tension required to achieve this stability. MethodsTen knee specimens were investigated; femur and tibia were clamped to a loading-frame; constant displacement rate was applied and resulting tension force was measured. Joint stability was determined as the slope change in the force/displacement curve, representing the ligaments' elastic-region activation; the tension required to reach functional stability is the span between ligaments toe-region and this point. Intact, ACL(Anterior-Cruciate-Ligament)-resected and ACL&PCL(Posterior-Cruciate-Ligament)-resected knees were tested. Different flexion angles were tested. ResultsResults demonstrated an overall tension of 40-50N to be enough to reach stability in intact knees. Similar values are sufficient in ACL-resected knees; higher tension is required (up to 60N) after ACL&PCL resection; slightly higher values were found for 60° flexion. Results agree with other experimental studies, showing that the tensions required to stabilize the joint are lower than the ones currently applied via surgical tensioners. ConclusionTo reach functional stability, surgeons should consider such results intraoperatively to avoid ligament laxity or over-tensioning.

The unreamed tibial nail (UTN) combines the advantages of the external fixator (preservation of the cortical blood supply) with that of conventional intramedullary nailing (closed system, high patient comfort, no pin problems) in the treatment of the lower leg fracture [5]. Within 1 year (III/92 to III/93) 31 closed and 2 open fractures were stabilised with UTN. In 67% (22 persons) we found fractures of the A1, A2 and A3 types according to the AO classification. In 6 patients there was a combined lesion with involvement of the ankle joint. A follow-up of 27 patients was done, extending to an average of 6 months postoperatively. The clinical and radiological results were excellent in 26; average fracture healing time was about 12-14 weeks.

Many unstable fractures and fracture dislocations of the lower thoracic and the lumbar spine are treated operatively. Internal fixation is mostly done via a posterior approach, anchoring the screws in the pedicles of the vertebrae. In the Traumatology Section of the Department of Surgery, Graz University, three different implantation systems have been employed in recent years. Sixty of all the patients operated on were available for follow-up an average of 36 months after operation. We compared them with respect to type of implant, paying special attention to any loss of reduction.