Computed tomography-based radiostereometric analysis in orthopedic research: practical guidelines.

Early implant migration is an indicator of the long-term survival/failure of implants. CT-based radio-stereometric analysis (CT-RSA) is a precise method for measuring and visualizing implant migration in vivo using image processing of CT scans. This makes the method widely applicable to orthopedic researcher.

A randomized double-blind noninferiority trial, evaluating migration of a cemented vitamin E-stabilized highly crosslinked component compared with a standard polyethylene component in reverse hybrid total hip arthroplasty.

Aims: Radiostereometric analysis (RSA) studies of vitamin E-doped, highly crosslinked polyethylene (VEPE) liners show low head penetration rates in cementless acetabular components. There is, however, currently no data on cemented VEPE acetabular components in total hip arthroplasty (THA). The aim of this study was to evaluate the safety of a new cemented VEPE component, compared with a conventional polyethylene (PE) component regarding migration, head penetration, and clinical results.

Osteoclasts in Periprosthetic Osteolysis: The Charnley Arthroplasty Revisited.

Background: Periprosthetic osteolysis by polyethylene wear debris-triggered osteoclasts is viewed as the main pathophysiological pathway in aseptic loosening in total hip arthroplasty. The present aim was to study osteoclast occurrence in osteolytic lesions in early and late revisions of the Charnley low-friction torque arthroplasty (CLFA).

Methods: Biopsies of the soft interface membrane and the adjacent bone were taken from osteolytic lesions during revision of 16 loose CLFA, early (2-6 years) or late (>10 years) after primary surgery.

Operational strategies to manage non-elective orthopaedic surgical flows: a simulation modelling study.

Objectives: To explore the value of simulation modelling in evaluating the effects of strategies to plan and schedule operating room (OR) resources aimed at reducing time to surgery for non-elective orthopaedic inpatients at a Swedish hospital.

Methods: We applied discrete-event simulation modelling. The model was populated with real world data from a university hospital with a strong focus on reducing waiting time to surgery for patients with hip fracture.

Abductor Muscle Function and Trochanteric Tenderness After Hemiarthroplasty for Femoral Neck Fracture.

Objectives: To compare the abductor muscle function and trochanteric tenderness in patients operated with hemiarthroplasty using the direct lateral (DL) or posterolateral (PL) approach for displaced femoral neck fracture.

Design: Prospective cohort study.

Setting: A secondary teaching hospital.

Debridement, antibiotics and implant retention in early periprosthetic joint infection.

Introduction: Periprosthetic joint infection (PJI) is a devastating complication in hip arthroplasty surgery. Debridement, antibiotics (AB) and implant retention (DAIR) is recommended in early PJI in association with stable implants. The aim of this study was to evaluate the success rate of DAIR in early PJI (<4 weeks) and to identify factors predicting the outcome.

Unpacking the key components of a programme to improve the timeliness of hip-fracture care: a mixed-methods case study.

Background: Delay to surgery for patients with hip fracture is associated with higher incidence of post-operative complications, prolonged recovery and length of stay, and increased mortality. Therefore, many health care organisations launch improvement programmes to reduce the wait for surgery. The heterogeneous application of similar methods, and the multifaceted nature of the interventions, constrain the understanding of which method works, when, and how.

Good stability but high periprosthetic bone mineral loss and late-occurring periprosthetic fractures with use of uncemented tapered femoral stems in patients with a femoral neck fracture.

Background And Purpose: We previously evaluated a new uncemented femoral stem designed for elderly patients with a femoral neck fracture and found stable implant fixation and good clinical results up to 2 years postoperatively, despite substantial periprosthetic bone mineral loss. We now present the medium-term follow-up results from this study.

Patients And Methods: In this observational prospective cohort study, we included 50 patients (mean age 81 (70-92) years) with a femoral neck fracture.

Total hip replacement versus open reduction and internal fixation of displaced femoral neck fractures: a randomized long-term follow-up study.

Background: Clinical trials with short and intermediate-term follow-up have demonstrated superior results for total hip replacement as compared with internal fixation with regard to hip function and the need for secondary surgery in elderly patients with a displaced intracapsular femoral neck fracture. The aim of the present study was to compare the results of total hip replacement with those of internal fixation over a long-term follow-up period of seventeen years.

Methods: We enrolled 100 patients who had sustained a femoral neck fracture in a single-center, randomized controlled trial;all patients had had a healthy hip before the injury.

The effect of weekly risedronate on periprosthetic bone resorption following total hip arthroplasty: a randomized, double-blind, placebo-controlled trial.

Background: Bone loss leading to late-occurring periprosthetic femoral fracture is a mode of failure in cementless total hip arthroplasty. The aim of this trial was to investigate the effect of a bisphosphonate, risedronate, on femoral periprosthetic bone resorption following total hip arthroplasty in patients with osteoarthritis of the hip.

Methods: We enrolled seventy-three patients between the ages of forty and seventy years who were scheduled to undergo total hip arthroplasty in a single-center, randomized, double-blind, placebo-controlled trial.

Ureaplasma urealyticum infection in total hip arthroplasty leading to revision.

We describe an infection with Ureaplasma urealyticum causing rapid loosening of a cemented total hip arthroplasty. When reviewing the literature we found that no such case has been reported previously. Taking intraoperative cultures for U urealyticum during revision surgery is not a standard procedure.

Large femoral bone loss after hip revision using the uncemented proximally porous-coated Bi-Metric prosthesis: 22 hips followed for a mean of 6 years.

Background And Purpose: Periprosthetic bone loss after uncemented femoral hip revision is a matter of concern. We have used a proximally porous- and hydroxyapatite-coated prosthesis (Bi-Metric) in revision since 1989 and now we report the bone changes. This prosthesis is intended to distribute the forces more evenly and to avoid proximal femoral unloading.

Good results with an uncemented proximally HA-coated stem in hip revision surgery: 62 hips followed for 2-13 years.

Background And Purpose: Proximal bone loss due to stress-shielding is a matter of concern after uncemented femoral hip revision. We have used short, proximally hydroxyapatite-coated prostheses in revision since 1989, and we now report the results.

Methods: 60 patients (62 hips) were revised because of aseptic loosening.

Continuous bone loss around a tapered uncemented femoral stem: a long-term evaluation with DEXA.

Background: Periprosthetic bone loss is a well-documented phenomenon after uncemented total hip arthroplasty (THA); however, little is known about how bone mineral density (BMD) changes after 2 years.

Patients And Methods: 14 patients with hip arthrosis (group A) were operated with a proximally porous- and hydroxyapatite-coated stem and followed for 10 years with DEXA, radiographs and Harris hip score (HHS). Another group of 14 patients (group B) was evaluated at 6 and 14 years using the same prosthesis and protocol.

Periprosthetic proximal bone loss after uncemented hip arthroplasty is related to stem size: DXA measurements in 138 patients followed for 2-7 years.

Background: Periprosthetic bone loss occurs around uncemented femoral stems and may be influenced by the stem size.

Patients And Methods: We studied 138 consecutive patients, 3 (2-7) years on average after a total hip arthroplasty operation (THA) for unilateral osteoarthritis with the Bi-Metric uncemented femoral stem. We analyzed Harris hip score and bone mineral density.