Stair stepping motion is important in daily living, similar to gait. In this study, we did a Kinematic Analysis of total knee arthroplasty during stair-stepping. A total of 20 patients implanted with Bi-Surface 5PS were assessed. The Bi-Surface knee is a posterior-cruciate substitute prosthesis with a unique ball-and-socket joint in the mid-posterior portion of the femoral and tibial components. This joint functions as a posterior stabilizing cam mechanism and as a load-bearing surface in flexion. Patients were examined during stair-stepping motion using a 2-dimensional to 3-dimensional registration technique. The kinematic pattern in step up was a medial pivot, in which the level of anteroposterior translation was very small. In step down, the kinematic pattern was neither pivot shift nor rollback. From minimum to maximum flexion, anterior femoral translation occurred slightly. However, it became clear in this study that the joint's stability during stair-stepping was affected by the design of the femorotibial joint rather than Post/Cam engagement.
Aseptic loosening and osteolysis may cause significant periprosthetic femoral bone destruction, often necessitating bypass of the deficient proximal femur to obtain stable fixation in the distal diaphysis. The purpose of the present study was to report our results of femoral component revision using a distally locked revision femoral stem for the treatment of the severe proximal femoral bone loss. We evaluated 21 hips in 20 patients who underwent revision hip arthroplasty associated with Paprosky grade-IIIB or IV femoral deficiencies. Three hips were associated with a Vancouver type-B3 periprosthetic femoral fracture. The mean age at the time of revision was 70.8 (51–82) years old with 5 men and 15 women. The mean duration of follow-up was 5.1 years. The femoral implant used for the revision was the Cannulok Revision Prosthesis in 16 hips and the Huckstep interlocking stem in five. Gaps between the stem and the host bone were filled and impacted with bone chips and morselized bone prior to stem insertion. One femoral implants were resected because of deep infection Subsidence was absent and stable fixation was achieved in all patients. Non-progressive radiolucent lines in zones 1 and 7 according to Gruen’s classification were detected in five cases. Cortical hypertrophy around the interlocking screws were seen in ten cases. No disadvantages or complications of the interlocking screws were observed. All the fractures have united within three to five months. Intraoperative fractures in the diaphyseal area occurred in five hips in which trochanteric osteotomy was used. A diaphyseal fixation of the femoral stem with distal interlocking screws appears to provide primary axial and rotational stability of the prosthesis and early mobilization. This implant may provide a satisfactory alternative for the management of revision hip surgery in the presence of a loose femoral component with massive bone loss. Longer-term follow-up data from this study will be needed to confirm these outcomes.
Aseptic loosening and osteolysis may cause significant periprosthetic femoral bone destruction, often necessitating bypass of the deficient proximal femur to obtain stable fixation in the distal diaphysis. The purpose of the present study was to report our results of femoral component revision using a distally locked revision femoral stem for the treatment of the severe proximal femoral bone loss. We evaluated 21 hips in 20 patients who underwent revision hip arthroplasty associated with Paprosky grade-IIIB or IV femoral deficiencies. Three hips were associated with a Vancouver type-B3 periprosthetic femoral fracture. The mean age at the time of revision was 70.8 (51–82) years old with 5 men and 15 women. The mean duration of follow-up was 5.1 years. The femoral implant used for the revision was the Cannulok Revision Prosthesis in 16 hips and the Huckstep interlocking stem in five. Gaps between the stem and the host bone were filled and impacted with bone chips and morselized bone prior to stem insertion. One femoral implants were resected because of deep infection Subsidence was absent and stable fixation was achieved in all patients. Non-progressive radiolucent lines in zones 1 and 7 according to Gruen’s classification were detected in five cases. Cortical hypertrophy around the interlocking screws were seen in ten cases. No disadvantages or complications of the interlocking screws were observed. All the fractures have united within three to five months. Intraoperative fractures in the diaphyseal area occurred in five hips in which trochanteric osteotomy was used. A diaphyseal fixation of the femoral stem with distal interlocking screws appears to provide primary axial and rotational stability of the prosthesis and early mobilization. This implant may provide a satisfactory alternative for the management of revision hip surgery in the presence of a loose femoral component with massive bone loss. Longer-term follow-up data from this study will be needed to confirm these outcomes.
Total Knee Arthroplasty (TKA) has been widely performed and successful clinical outcomes have been achieved for the patients with knee osteoarthritis which is generally known to cause ADL problem. Clinical and radiographic evaluations are commonly used when evaluating postoperative outcomes, among which kinetic analysis and gait analysis are considered essential to investigate the more detailed effect of the treatment. There is a controversy whether performing TKA on both knees simultaneously is appropriate in treating patients with bilateral knee osteoarthritis, in terms of the speed and effectiveness of gait recovery. In this study, we reviewed the significance of performing simultaneous bilateral TKA, by the results of preoperative and postoperative gait analysis.
