Accuracy and Precision of Acetabular Component Placement With Imageless Navigation in Obese Patients

Background

Obesity is a risk factor for acetabular component malposition when total hip arthroplasty is performed with manual techniques. The utility of imageless navigation in obese patients remains unknown. This study compared the accuracy and precision of imageless navigation for component orientation between obese and nonobese patients.

Projected Economic Burden of Periprosthetic Joint Infection of the Hip and Knee in the United States

BackgroundIn addition to the significant morbidity and mortality associated with periprosthetic joint infection (PJI), the cost of treating PJI is substantial. Prior high-quality national estimates of the economic burden of PJI utilize data up to 2009 to project PJI growth in the United States through 2020. Now in the year 2020, it is appropriate to evaluate these past projections and incorporate the latest available data to better understand the current scale and burden of PJI in the United States.MethodsThe Nationwide Inpatient Sample (2002-2017) was used to identify rates and associated inpatient costs for primary total knee arthroplasty (TKA) and total hip arthroplasty (THA) and PJI-related revision TKA and THA. Poisson regression was utilized to model past growth and project future rates and cost of PJI of the hip and knee.ResultsUsing the most recent data, the combined annual hospital costs related to PJI of the hip and knee were estimated to be $1.85 billion by 2030. This includes $753.4 million for THA PJI and $1.1 billion for TKA PJI, in that year. Increases in PJI costs are mainly attributable to increases in volume. Although the growth in incidence of primary THA and TKA has slowed in recent years, the incidence of PJI and the cost per case of PJI remained relatively constant from 2002 to 2017.DiscussionUnderstanding the current and potential future financial burden of PJI for surgeons, patients, and healthcare systems is essential. There is an urgent need for efficacious preventive strategies in reducing rates of PJI after THA and TKA.     

Posterior Soft Tissue Repair After Primary THA is Durable at Mid-term Followup: A Prospective MRI Study

Background

The enhanced posterior soft tissue repair has reduced the frequency of dislocation after primary THA performed through the posterolateral approach. However, the long-term integrity of the repair is unknown and could influence surgeon choice regarding surgical technique and THA approach.

Questions/Purposes

We asked: (1) What is the durability of the enhanced posterior soft tissue repair at a minimum of 49 months using MRI to evaluate soft tissue to bone integrity? (2) How does the appearance of the posterior soft tissues change during this time? (3) Are there patient characteristics associated with the long-term imaging appearance of the posterior repair?

Methods

All patients without a contraindication for MRI who were undergoing unilateral primary uncemented THA through a posterior approach between February and May 2005 were eligible for inclusion. Ninety percent consented to participate (36 of 40 patients), and 30 patients were followed prospectively with MRI postoperatively and again at 3 months; of those, 22 (73%; 12 men, 10 women) completed the study by having another MRI study at a minimum of 49 months (mean, 51 months; range, 49–59 months). Each patient underwent metal-artifact–reduction sequence MRI to evaluate the integrity of the posterior soft tissues, which had been repaired anatomically during primary THA at a minimum of 4 years earlier. The results were compared with those of prior MR images obtained immediately after surgery and at 3 months postoperatively. All patients were given a self-reported modified Harris hip score at the time of the most recent MRI study (maximum score = 81).

Results

At latest followup, 21 of 22 (96%) patients had a posterior capsule in contact with bone, and 21 of 22 (96%) had an intact quadratus femoris. Twenty-one patients (96%) had soft tissue or a scar from the piriformis and conjoined tendons in continuity with bone. In these cases, the interface between the piriformis and conjoined tendons and the greater trochanter observed immediately postoperatively and at 3 months postoperatively became filled with hypointense tissue, with signal characteristics similar to tendon. Time from surgery was most associated with changes in native tendon-to-bone distances (p < 0.001) and MRI signal intensity of the repair (p < 0.001).

Conclusions

At followup of just more than 4 years, the posterior capsule and quadratus femoris most often were healed to bone. In the majority of patients, scar tissue between the piriformis and conjoined tendons and bone matured to achieve orientation and signal intensity resembling native tendon. We believe the enhanced posterior soft tissue repair facilitates this process. Our results provide a plausible explanation for improved postoperative stability observed in patients receiving an enhanced soft tissue repair compared with those in whom a repair is not performed.

Level of Evidence

Level IV, therapeutic study.     

Anteroposterior Radiographs Are More Accurate than Cross-Table Lateral Radiographs for Acetabular Anteversion Assessment: a Retrospective Cohort Study

Background

Measuring acetabular anteversion is relevant to routine follow-up of total hip arthroplasties (THAs) and for malfunctioning THAs. Imageless navigation facilitates acetabular component orientation relative to the anterior pelvic plane (APP) or to the APP adjusted for sagittal pelvic tilt (PT). The optimal plain radiographic method for the postoperative assessment of anteversion is not agreed upon.

Questions/Purposes

(1) Do anteversion measurements on plain radiographs correlate more with APP anteversion or PT-adjusted anteversion? (2) Do measurements of anteversion performed on supine anteroposterior (AP) radiographs more accurately reflect intraoperative anteversion values for navigated THA compared to anteversion measured on cross-table lateral (CL) radiographs?

Methods

Seventy patients receiving primary navigated THA were included. APP and PT-adjusted anteversion were recorded; the latter defined the intraoperative target for anteversion. Postoperative anteversion was measured on supine AP pelvis radiographs with computer software and CL radiographs with conventional methods. Intraoperative measurements were used as the reference standards for comparisons.

Results

Mean intraoperative APP anteversion was 20.6°?±?5.6°. Mean intraoperative PT-adjusted anteversion was 22.9°?±?4.5°. Mean anteversion was 22.7°?±?4.7° on AP radiographs and 27.2°?±?4.2° on CL radiographs (p?<?0.001). Only correlations between PT-adjusted anteversion and radiographic assessments of anteversion were significant. The mean difference between PT-adjusted anteversion and anteversion on AP radiographs was ?0.2°?±?4.3°, while the mean difference between the PT-adjusted anteversion and anteversion measured on CL radiographs was 4.3?±?5.1° (p?<?0.001).

Conclusion

Plain film assessment of anteversion was more accurate on supine AP radiographs than on CL radiographs, which overestimated acetabular anteversion.

     

Patient Satisfaction After Total Knee Replacement: A Systematic Review

Background:

The quality and state of satisfaction reporting after total knee replacement (TKR) is variable.

Questions/Purposes:

The purposes of this systematic review were (1) to examine the available literature on patient satisfaction after TKR, (2) to evaluate the quality of available evidence, and (3) to identify predictors of patient satisfaction after TKR.

Methods:

A systematic review of the MEDLINE database was performed. The initial search yielded 1219 studies. The inclusion criteria were English language, clinical outcome study with primary outcome related to TKR for osteoarthritis, and patient-reported satisfaction included as an outcome measure. Studies were assessed for demographics, methodology for reporting satisfaction, and factors influencing satisfaction.

Results:

Two hundred eight studies, including 95,560 patients who had undergone TKR, met all inclusion and exclusion criteria; 112 (53.8%) of these studies were published in the past 3 years. Satisfaction was most commonly measured using an ordinal scale. Twenty-seven studies (13%) used a validated satisfaction survey. Eighty-three percent of studies reported more than 80% satisfaction. The most commonly reported predictor of satisfaction was post-operative patient-reported functional outcome. Pre-operative anxiety/depression was the most common pre-operative predictor of dissatisfaction.

Conclusion:

There are numerous studies reporting patient satisfaction after TKR, and publication on the topic has been increasing over the past decade. However, the majority of studies represent lower levels of evidence and use heterogeneous methods for measuring satisfaction, and few studies use validated satisfaction instruments. In general, the majority of studies report satisfaction rates ranging from 80 to 100%, with post-operative functional outcome and relief of pain being paramount determinants for achieving satisfaction.

     

Revision Total Knee Arthroplasty for Periprosthetic Joint Infection Is Associated With Increased Postoperative Morbidity and Mortality Relative to Noninfectious Revisions

Background

Periprosthetic joint infection (PJI) after primary total knee arthroplasty (TKA) is a devastating complication. The short-term morbidity profile of revision TKA performed for PJI relative to non-PJI revisions is poorly characterized. The purpose of this study is to determine 30-day postoperative outcomes after revision TKA for PJI, relative to primary TKA and aseptic revision TKA.

Histology, not lymph node involvement, predicts long-term survival in bronchopulmonary carcinoids

Recently, the incidence of bronchopulmonary carcinoid has increased substantially, whereas survival associated with both subtypes has declined. We reviewed our experience with bronchopulmonary carcinoid to identify factors associated with long-term survival. We reviewed our cancer registry from 1985 to 2009 for all patients undergoing surgical resection for bronchopulmonary carcinoid. Cox regression analysis was used to evaluate prognostic factors. Fifty-two patients met criteria for inclusion. Forty-three patients (82%) presented with typical histology. The likelihood of lymph node metastasis was similar for patients with typical histology and patients with atypical histology. For patients with typical histology, the 5-year survival rates with and without lymph node metastases were 100 per cent and 97 per cent, respectively (P = 0.420). The overall survival rate for patients with typical histology (97% at 5 years; 72% at 10 years) was significantly better than for patients with atypical histology (35% at 5 years, 0% at 10 years) (P < 0.001). Univariate and multivariate analyses demonstrated that long-term survival was associated with histology but not lymph node involvement (hazards ratio = 14.6, 95% confidence interval: 1.7, 125.2). Our data suggests that long-term survival is associated with histology, not lymph node involvement. We found tumor histology to be the strongest predictor of long-term survival in patients with pulmonary carcinoid tumors.     

Social media: physicians-to-physicians education and communication

Purpose of review

Physician to physician communication is essential for the transfer of ideas, surgical experience, and education. Social networks and online video educational contents have grown exponentially in recent years changing the interaction among physicians.

Recent findings

Social media platforms can improve physician-to-physician communication mostly through video education and social networking. There are several online video platforms for orthopedic surgery with educational content on diagnosis, treatment, outcomes, and surgical technique. Social networking instead is mostly centered on sharing of data, discussion of confidential topics, and job seeking. Quality of educational contents and data confidentiality represent the major drawbacks of these platforms.

Summary

Orthopedic surgeons must be aware that the quality of the videos should be better controlled and regulated to avoid inaccurate information that may have a significant impact especially on trainees that are more prone to use this type of resources. Sharing of data and discussion of confidential topics should be extremely secure according the HIPAA regulations in order to protect patients’ confidentiality.