Total Joint Arthroplasty (TJA) is associated with significant blood loss and allogeneic transfusion rates over 20% nationally. However, there are significant risks associated with allogeneic blood transfusion. Such risks include viral disease transmission, transfusion reactions, fluid overload, cost to the healthcare system, and prosthetic joint infection (PJI). As such, avoidance of transfusion is advised.

Minimising transfusion rates begins in the pre-operative phase and continues during the operative and post-operative phases. A lower pre-operative hemoglobin level is the strongest predictor for the potential need of allogeneic blood transfusion after TJA. Other risk factors include the use of general anesthesia, higher Charlson comorbidity index, female gender, and longer duration of surgery.

We present a comprehensive blood management strategy that encompasses all three phases. In the pre-operative phase, the most important intervention is screening for the presence of, and correcting, any preexisting anemia. During the operative phase, the use of hypotensive regional anesthesia is utilised when appropriate. In addition, tranexamic acid (TXA) is liberally utilised, either topically or intravenously. In the post-operative phase, transfusion triggers are carefully scrutinised. Only patients with symptomatic anemia despite fluid resuscitation are considered for blood transfusion. The threshold for transfusion is individualised for each patient, and is not merely based on a laboratory value.

Utilising this approach, we have decreased our transfusion rates from over 20% to just over 10%, even with a relatively unhealthy population at a tertiary referral center. The main driver of this reduction was the introduction of TXA as the standard of care for all TJA patients. TXA has been shown in multiple studies to be both safe and effective.

Hip dislocation and recurrent instability continue to be a major cause of failure despite advances in materials to optimise offset and head size. The most common cause of revision after total hip arthroplasty (THA) remains recurrent dislocation (22.5%). Dislocation rates following revision THA are even higher than primary THA, and can be as high as 27%.

Dual mobility acetabular components were introduced in 1974 by Bousquet to reduce dislocation risk and maintain the low friction concept introduced by Charnley. Dual mobility THA has gained wide acceptance in Europe, but there are still concerns regarding its long-term outcomes in the United States. However, even with noncrosslinked polyethylene and poor implant design, survivorship at 22 years has been shown to be 75%.

Little has been published on modular dual mobility (MDM) THA in the revision setting. During revision THA, the benefits of enhanced stability may outweigh the risks of potential unforeseen complications. We present the early results of MDM revision THAs with a low complication rate. In our series, we had a 1.6% dislocation rate, which is significantly lower than what has been published in the literature. However, we urge caution with its use in off label cases, as one of the dislocations was intraprosthetic upon attempted reduction requiring revision to a constrained liner.

Dislocation remains a major concern after total hip replacement, and is often attributed to malposition of the components. The optimum position for placement of the components remains uncertain. We have attempted to identify a relatively safe zone in which movement of the hip will occur without impingement, even if one component is positioned incorrectly. A three-dimensional computer model was designed to simulate impingement and used to examine 125 combinations of positioning of the components in order to allow maximum movement without impingement. Increase in acetabular and/or femoral anteversion allowed greater internal rotation before impingement occurred, but decreases the amount of external rotation. A decrease in abduction of the acetabular components increased internal rotation while decreasing external rotation. Although some correction for malposition was allowable on the opposite side of the joint, extreme degrees could not be corrected because of bony impingement.

We introduce the concept of combined component position, in which anteversion and abduction of the acetabular component, along with femoral anteversion, are all defined as critical elements for stability.