The Knee
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The purpose of the current study was to investigate inpatient recovery process during relaxed standing, and to clarify the question of when postoperative standing function would improve beyond preoperative level of function following total knee arthroplasty (TKA). Thirty patients with bilateral knee osteoarthritis, averaged 75 years old, participated. Subjects underwent unilateral TKA. ⋯ After TKA, knee flexion angle during standing became maximum (20.0) on postoperative day 4. Thereafter, subjects could gradually extend the knee, and on postoperative day 16, it (14.3 degrees ) was smaller. From our results, subjective pain was significantly reduced from postoperative day 8, and objective knee condition, including vertical knee force on TKA side and knee flexion angle on TKA side during standing, significantly became better from postoperative day 17 and 16, respectively.
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We compared the distance of patellar subluxation (lateral patellar displacement) during MIS TKA arthrotomy among sequential variations of tourniquet application and soft tissue release in a consecutive series of 40 knees. The distance of patellar subluxation from the Whiteside's line was measured for every knee under four consecutive conditions; A) the tourniquet inflated with knee in full extension, B) no tourniquet pressure applied, C) the tourniquet inflated with knee in deep flexion, and D) the tourniquet inflated with knee in deep flexion and lateral tibial release (a limited subperiosteal soft tissue dissection including limited patellar fat pad excision and limited capsular release from the upper lateral tibial plateau). There were 28 women and 12 men with the average age of 70 years and the average BMI of 25.5. ⋯ However, there was no statistical difference of measured distance between group with condition B and C (p=0.40). In conclusion, when MIS TKA is performed using the tourniquet, inflating the tourniquet with knee in deep flexion provided better arthrotomy exposure than the knee in full extension. Combined inflating tourniquet in deep knee flexion and lateral tibial release provided the greatest arthrotomy visualization.
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We measured the location of the popliteal artery (PA) in extension and 90 degree of knee flexion by magnetic resonance images (MRI) to provide practical information to avoid PA injury. The MRIs of 30 knees of Korean male subject whose mean age was 20.7 were acquired in knee extension and 90 degree flexion. The distance from the posterior aspect of knee joint to the PA was measured at three levels on the axial images and one sagittal image. ⋯ The PA was located around 3 mm lateral to the PCL, and within 5 mm in extension and 10 mm in 90 degree flexion of the knee behind knee joint. It moves farther posteriorly in 90 degree flexion than in extension of the knee. The conventional wisdom of flexing the knee to prevent the PA injury was supported by this study.
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This study was designed to provide evidence that computer-navigated minimally invasive total knee arthroplasty (MIS CN-TKA) enables identical mechanical accuracy as conventional computer navigated total knee arthroplasty (CN-TKA) while reducing rehabilitation time and hospital stay of the patients. Two groups of 20 patients requiring total knee arthroplasty due to degenerative or posttraumatic knee osteoarthritis were included. Twenty consecutive patients received conventional CN-TKA and 20 consecutive patients received minimally invasive CN-TKA. ⋯ The advantages of CN-TKA are well known. Performing computer navigated TKA in combination with a minimally invasive approach in this study lead to a reduction of hospital stay and an initially increased ROM without differences in operating time and blood loss. Computer navigation in TKA preserves accurate coronal, sagittal and rotational components alignment even with a minimally invasive approach.
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The objective of this study was to investigate the influence of tibial tubercle osteotomy on postoperative outcome, intra- and postoperative complications, as well as postoperative clinical results and failures in primary total knee arthroplasty (TKA). In a continuous, consecutive series of 1474 primary TKA, we analysed 126 cases where a tibial tubercle osteotomy approach was performed and 1348 cases without tibial tubercle osteotomy. Before surgery, all patients underwent a systematic assessment that included a clinical examination, radiographs (stress hip-knee-ankle film [pangonogram], weight bearing, anteroposterior knee view, schuss view, profile and patellar axial view at 30 degrees, stress valgus and varus view) and International Knee Society scores. ⋯ Tibial tubercle osteotomy cannot be considered an entirely safe procedure in primary TKA as it is associated with local complications, particularly skin necrosis and fracture of the tibial tubercle. Therefore, tibial tubercle osteotomy should be performed only when necessary, i.e. in cases where there are difficulties gaining adequate surgical exposure, ligament balance and correct implant positioning. The procedure also demands considerable surgical experience to achieve a good outcome.