Conventional Cementless Total Hip Arthroplasty for Hip Osteoarthritis after Distal Trochanteric Transfer: A Report of Two Cases

Distal trochanteric transfer (DTT) has been widely performed to treat developmental dysplasia of the hip or Perthes disease. Total hip arthroplasty (THA) following DTT in patients with hip osteoarthritis is one of the most challenging procedures for hip surgeons, because great care must be taken regarding anatomical abnormalities of the greater trochanter and the soft tissue attached to the greater trochanter. To the best of our knowledge, there are no reports on THA after DTT. We herein report two cases of patients who underwent THA post DTT using cementless components. After THA, both patients developed abduction temporary contraction because of leg length extension and gluteus medius hypertension. However, in both cases, the contraction was reversible within two months and the final clinical result was good. Therefore, THA can be considered an effective and safe choice for treating osteoarthritis after DTT.

Predictive value of short-term migration in determining long-term stable fixation in cemented and cementless total knee arthroplasties

Aims Early implant migration measured with radiostereometric analysis (RSA) has been proposed as a useful predictor of long-term fixation of tibial components in total knee arthroplasty. Evaluation of actual long-term fixation is of interest for cemented components, as well as for cementless fixation, which may offer long-term advantages once osseointegration has occurred. The objective of this study was to compare the long-term migration with one- and two-year migration to evaluate the predictive ability of short-term migration data and to compare migration and inducible displacement between cemented and cementless (porous metal monoblock) components at least ten years postoperatively. Patients and Methods Patients who had participated in RSA migration studies with two-year follow-up were recruited to return for a long-term follow-up, at least ten years from surgery. Two cemented tibial designs from two manufacturers and one porous metal monoblock cementless tibial design were studied. At the long-term follow-up, patients had supine RSA examinations to determine migration and loaded examinations (single leg stance) to determine inducible displacement. In total, 79 patients (54 female) returned, with mean time since surgery of 12 years (10 to 14). There were 58 cemented and 21 cementless tibial components. Results Migration at one year and two years was significantly correlated with long-term migration (p < 0.001). Median migration at the long-term follow-up was 0.6 mm (maximum total point motion; interquartile range (IQR) 0.4 to 0.9) for the cemented group and 0.6 mm (IQR 0.3 to 1.1) for the cementless group with no difference between groups (p = 0.99). Inducible displacement was significantly lower for the cementless components (p < 0.001). Conclusion Long-term migration was strongly correlated with two-year migration. Although long-term migration was not different for cemented or cementless tibial components, inducible displacement at the long-term visit was significantly lower for these cementless components, suggesting superior fixation. These findings support the predictive value of short-term migration in determining long-term fixation. Cite this article: Bone Joint J 2019;101-B(7 Supple C):55–60

Primary elbow arthroplasty: problems and solutions

Prosthetic replacement of the elbow joint has continued to improve over time. Widespread implantation of certain designs has led to identification a few successful elements of elbow arthroplasty, as well as several opportunities for improvement. Current hot topics in elbow arthroplasty include triceps-preserving exposures, implantation of components with better-expected wear performance, management of the ulnar nerve, prevention of infection, and the development of successful cementless components. Total elbow arthroplasty has the potential to improve pain, function and quality of life for many patients with articular destruction secondary to inflammatory arthropathy or as a consequence of trauma. Continued advances in this field are key to make this operation as reliable and lasting as hip or knee arthroplasty.

Design and Biomechanics of the Oxford Knee

The description of the Oxford Knee starts with an explanation of the function of mobile bearings in knee prostheses. An obvious advantage is that the areas of contact between the joint surfaces are maximised. In this chapter, we shall show that wear at the polyethylene surfaces is thereby minimised and that optimal kinematics can be achieved with minimal risk of loosening. We will discuss the biomechanics of the cementless components and problems that may occur with the tibia.

Early Results of a Modular Cementless Tibial Component for Total Knee Arthroplasty

Cementless components in TKA have been used for almost 3 decades, despite mixed success rates. However, biologic fixation remains attractive, especially for younger patients, because of the potential of unlimited durability. This paper is the first to report results on a modular tibial base plate using trabecular metal as a fixation surface. Twenty-four primary TKAs were evaluated clinical and radiographically at mean 1.9 year followup. Excellent clinical results were obtained. There was no significant subsidence or change in orientation of any component. One component was probably loose radiographically but was insufficiently symptomatic to warrant revision. Five components showed nonprogressive radiolucent lines. One reoperation was performed for stiffness, at which time the components were well fixed. Thus, it would appear that excellent bony fixation can be achieved with a modular cementless tibial component with excellent short-term clinical results.