Aims. Eight-plates are used to correct
The three distinct phases of design and development of total knee replacement (TKR) were:. 1969–1985,. 1986–2000 and. 2000 to today and beyond. Hinge designs and early condylar designs highlight the first major period of TKR development from 1969 to 1985. These designs included but were not limited to the Waldius, Shiers, and GUEPAR hinges, Gunston’s Polycentric Knee in 1971, Freeman’s ICLH Knee in 1972, Coventry’s Geomedic Knee in 1972, St. George’s Sled Prosthesis in 1971, Marmor’s Modular Uni in 1971, Townley’s Condylar Design in 1972, Walker and Ranawat’s Duocondylar in 1971, Waugh’s UCI Knee in 1976, Eftekar’s Metal Backing in 1978, Murray and Shaw’s Metal Backed Variable Axis Knee in 1978, Insall and Burstein’s IB-1 Knee in 1978, the Kinematics in 1978, and finally Walker, Ranawat and Insall’s Total Condylar in 1978. The Total Condylar Knee, developed by Walker, Ranawat, and Insall between 1974 and 1978, has been the benchmark for all designs through the 20th century. My personal experience of cemented TKR from 1974–2009 has shown a survivorship of 89%–98% at 15–20 years. Similar data has been presented in several 10+ year follow-up studies. The next major phase of development gave birth to semi-constrained TKR, cruciate saving and substituting PS designs, improved instrumentation and improved cemented fixation. Other guiding principles involved improving alignment, managing soft-tissue balance for
In Total Knee Arthroplasty (TKA) restoring the mechanical alignment of the knee joint is essential. This can be improved by considering the individual variability in the angle between the mechanical and anatomical axes of the femur (FMA angle). However with the traditional instrumentation and the use of the most common fixed distal femoral resection angle of 6° we assume little or no variation in the FMA angles in different patients. In a previous study we showed that the FMA angle had a wide distribution and that there was a good correlation between the FMA angle and the pre-operative lower limb alignment in the coronal plane. Our hypothesis was that improved post operative limb alignment would be achieved with traditional instrumentation by individual measurement of the FMA angles pre-operatively and adjusting the distal femoral resections accordingly. In the study we compared the post-operative coronal limb alignment for a cohort of patients with a variable distal femoral resection angle to the previous cohort of fixed distal femoral resection angle. The study consisted of 103 patients undergoing 103 consecutive primary TKAs between October 2008 and March 2009. All patients had pre- and post-operative Hip-Knee-Ankle digital radiographs and had TKAs performed using a variable distal femoral cut angle. The FMA angle and the mechanical femoro-tibial (MFT) angles were measured in all cases. Inter-observer variation was measured by second observer readings. We compared our results with the group of 158 consecutive patients undergoing 174 primary TKAs operated between January and October 2007 using fixed distal femoral resection angle. Patient demographics of the two cohorts (age, gender, BMI) were similar. The pre-operative coronal deformity for the variable cohort was less than the fixed, mean 3.7° varus (SD 5.8°) compared to 4.7° varus (SD 7.9°). The FMA angles for the variable cohort ranged from 4° to 8°, (the fixed cohort from 2° to 9°). The variable valgus resection angles cohort showed a correlation between FMA and pre-operative MFT angles as had previously been shown in the fixed cohort (r = −0.499 and r = −0.346 respectively). Post op alignment showed that accuracy within ±5° increased from 86% (fixed resection angle group) to 96% (variable resection group). When using the more commonly quoted accuracy of within ±3°, this changed from 67% (fixed resection angle group) to 85% (variable resection group). These improvements were statistically significant (chi-squared 0.025 and 0.002, respectively). To further evaluate the effect of using variable angles we analysed the improvement of each of the different groups of deformity identified in the previous study (>
8° varus, 8° varus to 1° valgus, >
2° valgus). The range was reduced in both the extreme varus and valgus groups with the variable angles. The most significant improvement was found in the valgus group with the median reducing from 3° to 2° and range from 14° to 8°. It seems logical to use a variable distal femoral resection angle based on the patient’s individual anatomy. By doing so, our results show significant improvement of postoperative limb alignment compared to traditional method of using fixed distal femoral resection angle. In units where preoperative long leg film radiographs are available, measuring the FMA angle and setting the distal femoral resection angle guide accordingly improves the postoperative limb alignment. However, where long leg radiographs are not available, changing the distal femoral resection angle according to the pre-operative
The object of this study was to develop a method to assess the accuracy of an image-free total knee replacement navigation system in legs with normal or abnormal mechanical axes. A phantom leg was constructed with simulated hip and knee joints and provided a means to locate the centre of the ankle joint. Additional joints located at the midshaft of the tibia and femur allowed deformation in the flexion/extension, varus/valgus and rotational planes. Using a digital caliper unit to measure the coordinates precisely, a software program was developed to convert these local coordinates into a determination of actual leg alignment. At specific points in the procedure, information was compared between the digital caliper measurements and the image-free navigation system. Repeated serial measurements were undertaken. In the setting of normal alignment the mean error of the system was within 0.5°. In the setting of abnormal plane alignment in both the femur and the tibia, the error was within 1°. This is the first study designed to assess the accuracy of a clinically-validated navigation system. It demonstrates
Aims. In order to limit the amount of both medial and lateral dissection, the MIPO technique was developed for extraarticular fractures of the femur. In this prospective study we have evaluated the outcome of 34 cases of supracondylar or subtrochanteric fractures of the femur treated by MIPO technique via exclusive proximal and distal incisions, using a DCS. Material and methods. Between July 2000 and March 2003, 34 acute fractures (14 supracondylar and 20 subtrochanteric) in 33 patients were included in this study. The technique consisted of 5 major steps: 1. the insertion of the condylar screw using minimal incision; 2. the selection of DCS-plate by fluoroscopy; 3. the insertion of the DCS-plate beneath the vastus lateralis; 4. an additional minimal proximal or distal incision allows plate positioning and its slipping onto the condylar screw; 5. after the limb axis, length and rotation are confirmed by reliable clinical and radiological techniques, the plate was fixed to the shaft with 3 or 4 screws placed divergently. Results. All fractures healed within a mean time of 14 weeks (range 8–24 weeks). 1 late implant failure (plate screw breakage) in an extremely cominutive fracture did not required repeat fixation. At follow-up, there were 5
Introduction: Nowdays most of the health services focus on the reduction of expenses and the shorter hospital stay. For the patients is also important the faster rehabilitation in work and in full self-sufficiency. Patients and methods: Möller has published in 1997, that medial unicompartmental knee arthroplasty can be operated from a shorter mediopatellar approach. This technique is important not only for the shorter wound, but much more for the faster rehabilitation because of the preserve of the extensor mechanism of the knee. Between April 2000 and December 2002 we performed the minimal invasive medial unicompartmental knee arthroplasty in 36 cases. Our results were evaluated by the HSS knee score. The average follow up time was 24.7 months. We have compared our results to a similar group in age, number and follow up time, who has been operated in the traditional approach. Results: However the overall HSS results showed significant difference (95.3 &
84.8), we think that the subgroups presents the substance of it much better. There was significant difference in walking distance, stair climbing, range of movement and muscle power, and we did not find any significant difference in pain, transport, flexion contracture, instability, need for appliance and the
