The aim of this study is to verify the intra-rater and inter-rater reliability of intra-operative kinematics by hand in TKA using a computer assisted image-free navigation system. Total knee arthroplasty (TKA) was performed on the knees of twelve (12) patients with knee navigation by one surgeon. Patients were divided into two groups: Group A included six knees that were operated on with assistant A (senior joint surgeon); and Group B included the other six knees that were operated on with assistant B (resident). For each knee, axial rotation was evaluated three times by the operator and the assistant using a navigation system at 30°, 60°, 90°, 120° passive flexions by hand. Intra-class correlation coefficients (ICC) were calculated for each evaluation to examine intra-rater and inter-rater reliability.Introduction
Material and Methods
We report an intertrochanteric fracture in a patient who had undergone hip arthrodesis 30 years previously. A 53-year-old man was injured in a head-on car crash and was referred to our hospital for treatment. Plain radiographs showed an intertrochanteric fracture of the right proximal femur and deformity of the right hip joint. He had undergone hip arthrodesis surgery 30 years previously at another hospital. Computed tomography scan showed marked atrophy of the gluteus and iliopsoas muscles. He preferred undergoing total hip arthroplasty (THA) to internal fixation. THA was performed using the anterolateral approach with the patient in the supine position as he had undergone hip arthrodesis through the Smith–Petersen approach, and we were concerned about damaging the gluteus muscle and dislocation if we took the posterolateral approach. The femoral head was removed using curved chisels under fluoroscopy. A cementless THA (J Taper stem, Aquala polyethylene liner; Kyocera Medical Corporation, Osaka, Japan) was inserted and fixed appropriately. Full weight-bearing using a walking frame was allowed 2 weeks after the surgery. Six months after the operation, he was able to walk independently and had good range of movement of the hip joint but continued to have weakness in the abductor muscles. Very few cases of proximal femur fracture in a previously arthrodesed hip have been reported. Manzotti et al. reported a similar case but they performed open reduction and internal fixation. No previous reports in the literature describe THA for intertrochanteric fracture in an arthrodesed hip. The conversion of an arthrodesed hip to THA is technically challenging. It has a high risk of complications such as nerve injuries and hip instability. We were able to treat the patient successfully, but surgeons should carefully decide the treatment method depending on the case.
