RESUMEN
BACKGROUND: iASSIST is one of the novel accelerometer-based navigation systems for total knee arthroplasty (TKA). Although the accuracy of iASSIST compared with conventional instruments has been reported, such evaluations were performed on two-dimensional (2D) images (X-rays). This multi-center prospective randomized controlled trial aimed to assess component positioning between TKA with and without iASSIST by 3D image assessment, and to clarify whether the iASSIST provides any benefit with regard to alignment accuracy. METHODS: Eighty-three knees with primary knee osteoarthritis were enrolled in this study. iASSIST was used for distal femoral and proximal tibial resection in 42 knees (iA group) and a conventional guide was used in 41 knees (CONV group). At 6 months postoperatively, component alignment was evaluated with 3D images by the independent orthopaedic surgeons, and surgical parameters, range of motion and clinical outcomes were examined. RESULTS: The rate of knees who have the alignment within 3° of neutral compared with the iA group and CONV group were 92.9% (39/42) vs. 87.8% (36/41) for femur and 76.2% (32/42) vs. 56.1% (23/41) for tibia in the coronal plane, respectively, whereas in the sagittal plane, the rate was 85.7% (36/42) vs. 58.5% (24/41) for femur and 83.3% (35/42) vs. 78.0% (32/41) for tibia, respectively. Compared with the CONV group, the iA group had a significantly improved femoral alignment in the sagittal plane (P = 0.006). There were no clinical or patient-reported differences at 6 months postoperatively. CONCLUSIONS: The iASSIST provides technically high accuracy in femoral resection at TKA compared with a conventional procedure.
Asunto(s)
Artroplastia de Reemplazo de Rodilla/métodos , Rodilla/diagnóstico por imagen , Cirugía Asistida por Computador/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Fémur/fisiología , Fémur/cirugía , Humanos , Imagenología Tridimensional , Rodilla/cirugía , Masculino , Persona de Mediana Edad , Tempo Operativo , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/cirugía , Medición de Resultados Informados por el Paciente , Estudios Prospectivos , Rango del Movimiento Articular , Tibia/fisiología , Tibia/cirugíaRESUMEN
PURPOSES: Several studies have reported no differences in outcomes between total hip arthroplasty (THA) of osteotomized hips and primary hip THA. However, our results were worse after THA for converted osteotomized hips. Therefore, this study's aim was to clarify the differences between THA after osteotomy and primary THA for osteoarthritis in developmental dysplasia of the hip (DDH). METHODS: The data were collected retrospectively (December 1998-June 2013). The cohort contained patients with a previous osteotomy (40 femur osteotomies) for osteoarthritis with DDH who then underwent cementless THA (average 192 months after osteotomy). The clinical and radiographic outcomes of 40 hips (osteotomy group) were compared with a matched group of 40 hips after primary THA (primary group). THA was performed and investigated only in patients with DDH. RESULTS: The mean follow-up period of the osteotomy group was 133 months. One patient was lost to follow-up. They had significantly higher subluxation and a narrower canal than the primary group (p < 0.0001, 0.017, respectively). Preoperative and final Harris Hip Score values were worse in the osteotomy group than in the primary group (preoperative 35 vs. 44, p = 0.0009; final 88 vs. 96, p = 0.0001, respectively). Manual muscle strengths of the hip flexor at final follow-up were worse in the osteotomy group. Radiographic outcomes of the osteotomy group showed a larger postoperative leg length discrepancy and severe periprosthetic bone atrophy as judged by bone mineral density and stress shielding. CONCLUSION: Proximal femoral osteotomies showed worse outcomes after conversion THA at mid-term follow-up.
Asunto(s)
Artroplastia de Reemplazo de Cadera , Osteoartritis , Artroplastia de Reemplazo de Cadera/efectos adversos , Humanos , Osteotomía , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
PURPOSE: The influence of physiologic femoral bowing on range of motion (ROM) after total hip arthroplasty (THA) remains unknown. The purpose of this study was to investigate the morphology of the femur in patients who underwent THA, and to analyze the influence of femoral bowing on ROM due to implant impingement after THA. METHODS: The ROM was calculated from 100 hips in 90 patients who underwent THA using computed tomography data with a 3D dynamic analysis software. Lateral and anterior bowing angles of the femur were measured. A modular implant (Modulus system, Lima Corporate, Villanova di San Daniele del Friuli, Italy) was used for simulation. In all subjects, cup inclination, anteversion, and stem anteversion were set to 40°, 15°, and 30°, respectively. Multiple linear regression analyses were performed to assess the relationship between the morphology of the femur and ROM. RESULTS: Lateral bowing of the femur was demonstrated to be significantly correlated with age (r = 0.361, p < 0.001) and female sex (r = 0.315, p = 0.001). Lateral bowing of the femur was significantly positively correlated with flexion and internal rotation (Int-R) with 90° flexion. Anterior bowing was significantly associated with decreasing flexion, decreasing Int-R with 90° flexion and increasing Int-R with 45° flexion and 15° adduction. CONCLUSIONS: A ROM-optimized cup position cannot be calculated from femoral stem anteversion values alone; therefore, when surgeons position the cup in relation to the femoral stem anteversion, the influence of femoral bowing may also require consideration.