2021 Mark Coventry Award: Use of a smartphone-based care platform after primary partial and total knee arthroplasty: a prospective randomized controlled trial.

Aims: The purpose is to determine the non-inferiority of a smartphone-based exercise educational care management system after primary knee arthroplasty compared with a traditional in-person physiotherapy rehabilitation model.

Methods: A multicentre prospective randomized controlled trial was conducted evaluating the use of a smartphone-based care management system for primary total knee arthroplasty (TKA) and partial knee arthroplasty (PKA). Patients in the control group (n = 244) received the respective institution's standard of care with formal physiotherapy.

Large-diameter metal-on-metal total hip arthroplasty: dislocation infrequent but survivorship poor.

Background: Use of large-diameter metal-on-metal (MoM) articulations in THA increased, at least in part, because of the possibility of achieving improved joint stability and excellent wear characteristics in vitro. However, there have been subsequent concerning reports with adverse reactions to metal debris (ARMD), pseudotumors, and systemic complications related to metal ions.

Questions/purposes: The purpose of this study was to determine at a minimum of 2 years' followup (1) the proportion of patients who experienced a dislocation; (2) the short-term survivorship obtained with these implants; (3) the causes of failure and the proportion of patients who developed ARMD; and (4) whether there were any identifiable risk factors for revision.

Medial mobile bearing unicompartmental knee arthroplasty: early survivorship and analysis of failures in 1000 consecutive cases.

Unicompartmental knee arthroplasty (UKA) is a less invasive treatment for medial gonarthrosis. However, registry data have demonstrated higher revision and early failure rates. The purpose of this study is to report the early survivorship and failure modes in a series of 1000 consecutive medial mobile bearing UKA.

Smoking may be a harbinger of early failure with ultraporous metal acetabular reconstruction.

Background: Smoking is considered a risk factor for surgical complications in total hip arthroplasty (THA) and has been linked to a higher rate of aseptic loosening in uncemented acetabular components. Acetabular reconstruction with newer ultraporous metals in both complex primary and revision THA has increased survivorship but it is unclear whether smoking affects survival of these implants.

Questions/purposes: We reviewed our early experience with THA using ultraporous acetabular components to assess the incidence and etiology of early failure and examine if any preoperative variables, including smoking, related to failure.

Two-stage treatment of hip periprosthetic joint infection is associated with a high rate of infection control but high mortality.

Background: Periprosthetic infection after total hip arthroplasty (THA) is a devastating complication. Reported rates of infection control range from 80% to 95% but mortality rates associated with treatment of infected THA are also substantial and we suspect underreported.

Questions/purposes: For patients selected for two-stage treatment of infected THA we therefore determined (1) mortality; (2) rate of reimplantation; and (3) rate of reinfection.

A short tapered stem reduces intraoperative complications in primary total hip arthroplasty.

Background: While short-stem design is not a new concept, interest has surged with increasing utilization of less invasive techniques. Short stems are easier to insert through small incisions. Reliable long-term results including functional improvement, pain relief, and implant survival have been reported with standard tapered stems, but will a short taper perform as well?

Questions/purposes: We compared short, flat-wedge, tapered, broach-only femoral stems to standard-length, double-tapered, ream and broach femoral stems in terms of intraoperative complications, short-term survivorship, and pain and function scores.

Metal-on-metal vs metal-on-improved polyethylene bearings in total hip arthroplasty.

Major weaknesses of total hip arthroplasty (THA) in the 20th century were polyethylene wear and dislocation. Efforts to improve THA took several directions including improvement of polyethylene and use of metal-on-metal (MoM) articulations. Metal-on-metal articulations showed excellent early results, but concerns mount over hypersensitivity and increasing failure.

Unsatisfactory surgical learning curve with hip resurfacing.

Background: Hip resurfacing is considered by many to be a conservative alternative to conventional total hip arthroplasty. There are advantages and drawbacks to any procedure, and there is a learning curve associated with the introduction of any new technology. The purpose of this study is to report the complication rate, types of complications, and outcomes of hip resurfacing during the early experience of two high-volume hip surgeons.