Shaw Akizuki

The long-term outcome of high tibial osteotomy: A TEN- TO 20-YEAR FOLLOW-UP

We carried out a prospective study of 132 patients (159 knees) who underwent closed-wedge high tibial osteotomy for severe medial compartment osteoarthritis between 1988 and 1997. A total of 94 patients (118 knees) was available for review at a mean of 16.4 years (16 to 20). Seven patients (7.4%) (11 knees) required conversion to total knee replacement. Kaplan-Meier survival was 97.6% (95% confidence interval 95.0 to 100) at ten years and 90.4% (95% confidence interval 84.1 to 96.7) at 15 years. Excellent and good results as assessed by the Hospital for Special Surgery knee score were achieved in 87 knees (73.7%). A pre-operative body mass index > 27.5 kg/m(2) and range of movement < 100 degrees were risk factors predicting early failure. Although our long-term results were satisfactory, strict indications for osteotomy are required if long-term survival is required.

In Vivo Determination of Kinematics for Subjects Having a Zimmer Unicompartmental High Flex Knee System

The objective of this study was to determine the in vivo kinematics during weight-bearing and non-weight-bearing activities for subjects with a unicompartmental knee arthroplasty (UKA) designed for high flexion and implanted with minimally invasive techniques. A total of 30 UKAs implanted in 18 patients were analyzed. All patients were implanted with a medial Zimmer Unicompartmental High Flex Knee System (Zimmer Inc, Warsaw, Ind). Under fluoroscopic surveillance, each patient performed weight-bearing deep knee bend, normal gait, and passive flexion. The kinematics of the medial UKA was determined using a 3-dimensional model registration technique. On average, the implant experienced posterior femoral rollback and normal axial rotation during flexion. However, the kinematic patterns for each patient were not consistent, and the variability was high during flexion and stance phase of gait.

Fixation of a hydroxyapatite-tricalcium phosphate-coated cementless knee prosthesis. Clinical and radiographic evaluation seven years after surgery.

Miller-Galante II total knee arthroplasty (MG II TKA) was performed on 32 knees in 30 patients. On both the femoral and tibial components, the fibre-metal area was plasma-sprayed with hydroxyapatite-tricalcium phosphate (HA-TCP). The clinical and radiographic outcome was evaluated. A mean preoperative knee score of 26.0 +/- 18.6 (SD) increased to 97.5 +/- 3.5 and a mean pre-operative functional score of 21.7 +/- 15.0 (SD) increased to 83.4 +/- 12.4 at follow-up of seven years. Clear zones were common around the components at one month post-operatively but had completely disappeared after six months. An autopsy of a patient who underwent MG II TKA with HA-TCP two years previously, showed osteogenesis in all parts of the fibre-metal, and bone tissue comprised 77.7% of the interface. This coated prosthesis has good early fixation which is maintained at seven years with good clinical and radiographic outcomes.

In Vivo Kinematic Analysis of Cruciate-Retaining Total Knee Arthroplasty During Weight-Bearing and Non–Weight-Bearing Deep Knee Bending

The purpose of the present study was to evaluate the in vivo kinematics of the posterior cruciate ligament-retaining total knee arthroplasty during weight-bearing and non-weight-bearing deep knee bending and compare these 2 different conditions. We evaluated the in vivo kinematics of the knee using fluoroscopy and femorotibial translation relative to the tibia tray by 2-dimensional/3-dimensional registration. In the weight-bearing state, the femoral component showed central pivot and bicondylar posterior rollback pattern. During non-weight-bearing, the movement anteriorly occurred on both the medial and lateral side during early flexion, whereas bicondylar femoral component rollback occurred after that. During non-weight-bearing, both the medial and lateral condyle significantly moved anteriorly compared with the weight-bearing state during early flexion. However, bicondylar femoral rollback occurred under both these conditions.

Three cases of pseudogout complicated with unicondylar knee arthroplasty

Abstract. Pseudogout is an uncommon complication of arthroplasty, so it is important to distinguish pseudogout from infection. We experienced three patients with the acute onset of pseudogout after unicondylar knee arthroplasty (UKA). Treatment with nonsteroidal anti-inflammatory drugs (NSAID) and cooling improved the symptoms of all three patients, and there have been no further episodes. Because there is a large area uncovered by the UKA prosthesis, it is necessary to keep in mind the possibility of pseudogout affecting the operated knee.

Clinical Results and Influence of Patellofemoral Joint Design on the Stability of the Patellar Component in Miller-Galante Types I and II, and Nexgen Total Knee Arthroplasty

We report here on the long-term outcome of Miller-Galante (MG) I-type total knee arthroplasty (TKA) as well as the short-term outcomes of MGII hydroxyapatite (HA)-type TKA using cobalt-chrome (CoCr) fiber-metal coated with hydroxyapatite tricalcium phosphate and Nexgen-type TKA. We also describe the characteristics and drawbacks of these artificial joints, and report on the degree of stability of the patellar component as evaluated on skyline-view radiographs of the knee. In MGI, use of the metal-backed patellar component resulted in failure in 24% of cases. However, long-term follow-up (12 years) after surgery revealed that the cementless fixation using fiber-metal of titanium alloy provided good stability, without the development of aseptic loosening. Postoperative follow-up for 3 to 4 years after MGII-HA type TKA proved the usefulness of the materials used for the cementless fixation, and no radiolucent line was observed on radiographs. The skyline view radiographs indicated that the stability of the patellar component provided by MGII-HA and Nexgen is superior to that provided by MGI.

Familial Neurilemoma of the spinal cord in a mother and daughter

Neurilemoma of the spinal cord occurred in a mother and daughter. Case 1 was a 75-year-old woman with gait disturbance. Examination revealed weakness of the lower extremities, and magnetic resonance (MR) imaging showed an intradural extramedullary tumor at T12. After laminectomy, the histologic diagnosis was mixed Antoni type A and B neurilemoma. Case 2 was a 48-year-old woman (daughter of case 1). She presented with cervical pain and numbness of both hands. Examination revealed weakened intrinsic muscles of the right hand and paresthesia of the right upper arm. MR imaging showed a giant hourglass-shaped extradural tumor at C2 and C3. The histologic diagnosis was Antoni type A neurilemoma. Only six families with neurilemoma have been reported, including our patients. Gene analysis of such patients may clarify the etiology of neurilemoma.

Measured (Anatomical Reference) Resection Technique for Cruciate-Retaining Total Knee Arthroplasty

The following points are essential to achieve success with the measured (anatomical reference) resection technique for cruciate-retaining total knee arthroplasty. First, the component is placed according to the anatomical landmarks of the patient while taking care to avoid rotational error by the anterior reference method.

A case of femoral pseudoaneurysm after surgery for intertrochanteric fracture

In the field of orthopaedic surgery, vascular injury is not rare and not only occurs secondary to fracture but also includes iatrogenic injury. Traumatic pseudoaneurysm is a typical orthopaedic vascular complication. Pseudoaneurysm has been reported after orthopaedic surgery at various sites, including the foot, tibial diaphysis, knee joint, hip joint, shoulder joint, and lumbar spine [1]. Femoral pseudoaneurysm is a rare complication after surgery for fracture of the proximal femur, including subtrochanteric or intertrochanteric fracture, and it usually occurs when a compression hip screw (CHS) is used for fixation of the fracture. Here we report a case of pseudoaneurysm after insertion of an intramedullary hip screw for a fracture of the proximal femur, which is an extremely rare complication of intramedullary hip screw [2,3]. This case emphasizes that the possibility of pseudoaneurysm should be considered in patients with such intertrochanteric fractures and that surgeons should be ready to provide immediate treatment if required.