Contemporary outcomes of primary total hip arthroplasty in patients with inflammatory arthritis

Ninety-day postoperative mortality and complications in continuous and unselected single-stage revisions for chronic periprosthetic joint infection

PURPOSE

Single-stage revision has gained significant attention as a major surgical approach for periprosthetic joint infection (PJI). However, the 90-day mortality and complication profile of single-stage revision is poorly characterized. The purposes of this study were to determine the incidence rates of and identify the risk factors for 90-day postoperative mortality and complications of single-stage revision for chronic PJI.

METHODS

A retrospective review was conducted on patients who underwent single-stage revision for PJI between August 2000 and May 2022. Patient demographics, 90-day mortality, and postoperative complications were recorded. Complications were categorized into systemic and local complications. Patients in this study were further categorized into knee and hip revision groups. Univariate and multivariate logistic regression analyses were performed to identify significant independent predictors of the outcome measures.

RESULTS

348 patients (144 knees and 204 hips) were included in this study. The 90-day mortality rate was 0.9%. The incidence rates of postoperative complications in knee and hip surgeries were 31.3% and 19.6%, respectively. The most common complication was deep-vein thrombosis (DVT). Rheumatoid arthritis (RA) was the independent predictor of mortality. In the knee revision group, fungal infection was identified as the independent predictor of recurrent PJI; regular alcohol use was predictive of wound dehiscence. Among hip PJI patients, age ≥ 80 years was independently associated with DVT; RA was found to be a predictor of dislocation and wound dehiscence.

CONCLUSION

For continuous and unselected patients with chronic PJI, single-stage revision demonstrated a satisfactory 90-day mortality. Nevertheless, the 90-day postoperative complication rates after single-stage revision in both knee and hip groups were relatively high.

A prospective randomized controlled trial comparing CT-based planning with conventional total hip arthroplasty versus robotic arm-assisted total hip arthroplasty

Aims

Achieving accurate implant positioning and restoring native hip biomechanics are key surgeon-controlled technical objectives in total hip arthroplasty (THA). The primary objective of this study was to compare the reproducibility of the planned preoperative centre of hip rotation (COR) in patients undergoing robotic arm-assisted THA versus conventional THA.

Methods

This prospective randomized controlled trial (RCT) included 60 patients with symptomatic hip osteoarthritis undergoing conventional THA (CO THA) versus robotic arm-assisted THA (RO THA). Patients in both arms underwent pre- and postoperative CT scans, and a patient-specific plan was created using the robotic software. The COR, combined offset, acetabular orientation, and leg length discrepancy were measured on the pre- and postoperative CT scanogram at six weeks following surgery.

Results

There were no significant differences for any of the baseline characteristics including spinopelvic mobility. The absolute error for achieving the planned horizontal COR was median 1.4 mm (interquartile range (IQR) 0.87 to 3.42) in RO THA versus 4.3 mm (IQR 3 to 6.8; p < 0.001); vertical COR mean 0.91 mm (SD 0.73) in RO THA versus 2.3 mm (SD 1.3; p < 0.001); and combined offset median 2 mm (IQR 0.97 to 5.45) in RO THA versus 3.9 mm (IQR 2 to 7.9; p = 0.019). Improved accuracy was observed with RO THA in achieving the desired acetabular component positioning (root mean square error for anteversion and inclination was 2.6 and 1.3 vs 8.9 and 5.3, repectively) and leg length (mean 0.6 mm vs 1.4 mm; p < 0.001). Patient-reported outcome measures were comparable between the two groups at baseline and one year. Participants in the RO THA group needed fewer physiotherapy sessions postoperatively (median six (IQR 4.5 to 8) vs eight (IQR 6 to 11; p = 0.005).

Conclusion

This RCT suggested that robotic-arm assistance in THA was associated with improved accuracy in restoring the native COR, better preservation of the combined offset, leg length correction, and superior accuracy in achieving the desired acetabular component positioning. Further evaluation through long-term and registry data is necessary to assess whether these findings translate into improved implant survival and functional outcomes.

[Effectiveness of combined anteversion angle technique in total hip arthroplasty for treatment of ankylosing spondylitis affecting hip joint]

Objective

To explore the effectiveness of the combined anteversion angle technique in total hip arthroplasty (THA) for treating ankylosing spondylitis (AS) affecting the hip joint.

Methods

A retrospective analysis was conducted on the clinical data of 73 patients with AS affecting the hip joint who underwent THA between August 2018 and August 2021. According to whether the combined anteversion angle technique was used in THA, the patients were divided into study group (37 cases, combined anteversion angle technique was used in THA) and control group (36 cases, traditional THA). There was no significant difference in baseline data such as gender, age, body mass index, disease duration, preoperative Harris score, range of motion (ROM), acetabular anteversion angle, acetabular abduction angle, femoral anteversion angle, and combined anteversion angle between the two groups ( P>0.05). The operation time, hospital stay, and complications of the two groups were recorded and compared. The Harris score and hip ROM were compared between the two groups before operation, at 1, 3, 6, 12 months after operation, and at last follow-up. The acetabular component anteversion angle, femoral component anteversion angle, acetabular component abduction angle, and component combined anteversion angle were measured postoperatively.

Results

The operation time in the study group was significantly shorter than that in the control group ( P<0.05), and there was no significant difference in hospital stay between the two groups ( P>0.05). There was no intraoperative complication such as acetabular and proximal femoral fractures, neurovascular injuries in both groups, and the incisions healed by first intention. All patients were followed up 2-3 years, with an average of 2.4 years; there was no significant difference in the follow-up time between the two groups ( P>0.05). During the follow-up period, there was no complication such as hip dislocation, wound infection, delayed wound healing, deep venous thrombosis, and hip dislocation in both groups. The hip Harris score and ROM of the two groups gradually increased with time after operation, and the differences were significant when compared with those before operation ( P<0.05); the above two indicators of the study group were significantly better than those of the control group at each time point after operation ( P<0.05). Extensive bone ingrowth on the surface of the components could be observed in the anteroposterior X-ray films of the hip joint of the two groups at 12 months after operation, and the acetabular components was stable without femoral stem subsidence, osteolysis around the components, and heterotopic ossification. At last follow-up, the acetabular component anteversion angle, femoral component anteversion angle, and component combined anteversion angle in the study group were significantly superior to those in the control group ( P<0.05), except that there was no significant difference in the acetabular component abduction angle between the two groups ( P>0.05).

Conclusion

For patients with AS affecting the hip joint, the use of the combined anteversion angle technique during THA effectively promotes the recovery of hip joint function and enhances the postoperative quality of life of patients when compared to traditional THA.

Periprosthetic joint infection and immunity: Current understanding of host-microbe interplay

Periprosthetic joint infection (PJI) is a major complication of total joint arthroplasty. Even with current treatments, failure rates are unacceptably high with a 5-year mortality rate of 26%. Majority of the literature in the field has focused on development of better biomarkers for diagnostics and treatment strategies including innovate antibiotic delivery systems, antibiofilm agents, and bacteriophages. Nevertheless, the role of the immune system, our first line of defense during PJI, is not well understood. Evidence of infection in PJI patients is found within circulation, synovial fluid, and tissue and include numerous cytokines, metabolites, antimicrobial peptides, and soluble receptors that are part of the PJI diagnosis workup. Macrophages, neutrophils, and myeloid-derived suppressor cells (MDSCs) are initially recruited into the joint by chemokines and cytokines produced by immune cells and bacteria and are activated by pathogen-associated molecular patterns. While these cells are efficient killers of planktonic bacteria by phagocytosis, opsonization, degranulation, and recruitment of adaptive immune cells, biofilm-associated bacteria are troublesome. Biofilm is not only a physical barrier for the immune system but also elicits effector functions. Additionally, bacteria have developed mechanisms to evade the immune system by inactivating effector molecules, promoting killing or anti-inflammatory effector cell phenotypes, and intracellular persistence and dissemination. Understanding these shortcomings and the mechanisms by which bacteria can subvert the immune system may open new approaches to better prepare our own immune system to combat PJI. Furthermore, preoperative immune system assessment and screening for dysregulation may aid in developing preventative interventions to decrease PJI incidence.

Total Hip Arthroplasty in Hemophilic Patients: are their Results Similar to those of Nonhemophilic Patients?

Total hip arthroplasty (THA) is the mainstay therapy for patients with terminal hemophilic arthropathy of the hip. However, the largest case series published between 2017 and 2023 in the literature on THA in patients with hemophilia have found a higher 1-year infection rate (8.1% versus 3.4%) in hemophilia patients than in the general population, a higher rate of in-hospital bleeding complications (38.7% versus 16.1%), a higher length of stay (6 days versus 3 days) and a higher 30-day readmission rate (22.6% versus 4.1%). Finally, a lower 5-year survival rate has also been observed in hemophilia patients than in the general population (91.9% versus 95.3%). In the last decade there have been dramatically positive improvements in implant designs and hematological treatment, and therefore it does not seem that THA in hemophilia is so far from that in osteoarthritic patients.