Strikingly High Rates of Periprosthetic Joint Infection Following Revision Surgery for Periprosthetic Fractures Regardless of Surgery Timing

BACKGROUND

Periprosthetic fractures following total hip arthroplasty (THA) often occur in the early postoperative period. Recent data has indicated that early revisions are associated with higher complication rates, particularly periprosthetic joint infection (PJI). The purpose of this study was to assess the effect of timing of periprosthetic fracture surgery on complication rates. We hypothesized that complication rates would be significantly higher in revision surgeries performed within 3 months of the index THA.

METHODS

The Medicare Part A claims database was queried from 2010 to 2017 to identify patients who underwent surgery for a periprosthetic fracture following primary THA. Patients were divided based on time between index and revision surgeries: <1, 1 to 2, 2 to 3, 3 to 6, 6 to 9, 9 to 12, and >12 months. Complication rates were compared between groups using multivariate analyses to adjust for demographics, comorbidities, and types of revision surgery.

RESULTS

Of 492,340 THAs identified, 4,368 (0.9%) had a subsequent periprosthetic fracture requiring surgery: 1,725 (39.4%) at <1 month, 693 (15.9%) at 1 to 2 months, 202 (4.6%) at 2 to 3 months, 250 (5.7%) at 3 to 6 months, 134 (3.1%) at 6 to 9 months, 85 (19.4%) at 9 to12 months, and 1,279 (29.3%) at >12 months. The risk of PJI was 11.0% in the <1 month group, 11.1% at 1 to 2 months, 7.9% at 2 to 3 months, 6.8% at 3 to 6 months, 8.2% at 6 to 9 months, 9.4% at 9 to 12 months, and 8.5% at >12 months (P = .12). Adjusting for confounding factors, risk of PJI following periprosthetic fracture surgery was similar regardless of timing (P > .05). Rates of subsequent dislocation and aseptic loosening were also similar regardless of timing.

CONCLUSIONS

The risk of PJI following repeat surgery for a periprosthetic fracture was strikingly high regardless of timing (6.8 to 11.1%), underscoring the high-risk of complications.

Revision Surgery for Instability After Total Hip Arthroplasty: Does Timing Matter?

BACKGROUND

Instability is a common reason for revision surgery after total hip arthroplasty (THA). Recent studies suggest that revisions performed in the early postoperative period are associated with higher complication rates. The purpose of this study is to assess the effect of timing of revision for instability on subsequent complication rates.

METHODS

The Medicare Part A claims database was queried from 2010 to 2017 to identify revision THAs for instability. Patients were divided based on time between index and revision surgeries: <1, 1-2, 2-3, 3-6, 6-9, 9-12, and >12 months. Complication rates were compared between groups using multivariate analyses to adjust for demographics and comorbidities.

RESULTS

Of 445,499 THAs identified, 9298 (2.1%) underwent revision for instability. Revision THA within 3 months had the highest rate of periprosthetic joint infection (PJI): 14.7% at <1 month, 12.7% at 1-2 months, and 10.6% at 2-3 months vs 6.9% at >12 months (P < .001). Adjusting for confounding factors, PJI risk remained elevated at earlier periods: <1 month (adjusted odds ratio [aOR]: 1.84, 95% confidence interval [CI]: 1.51-2.23, P < .001), 1-2 months (aOR: 1.45, 95% CI: 1.16-1.82, P = .001), 2-3 months (aOR: 1.35, 95% CI: 1.02-1.78, P = .036). However, revisions performed within 9 months of index surgery had lower rates of subsequent instability than revisions performed >12 months (aOR: 0.67-0.85, P < .050), which may be due to lower rates of acetabular revision and higher rates of head-liner exchange in this later group.

CONCLUSION

When dislocation occurs in the early postoperative period, delaying revision surgery beyond 3 months from the index procedure may be warranted to reduce risk of PJI.

Partial Knee Arthroplasty: The State of the Art

Unicompartmental knee arthroplasty and patellofemoral arthroplasty were pioneered in the 1970s but abandoned by most in favor of total knee arthroplasty because of inconsistent early outcomes. Advancements in implant design, instrumentation, indications, and surgical techniques have enhanced results and led to a resurgence in both unicompartmental knee arthroplasty and patellofemoral arthroplasty for appropriate candidates. In appropriately selected patients, current implants and techniques provide surgeons the resources to carry out a surgical procedure that is simpler to perform and easier to recover from. Furthermore, unicompartmental knee arthroplasty is associated with fewer postoperative complications and lower mortality and is equal to or better than total knee arthroplasty.

Surgical Treatment of Acute Periprosthetic Knee Infection with Concurrent Presumed COVID-19: A Case Report

CASE

We report the case of a 64-year-old man who presented with a late onset of acute periprosthetic joint infection after total knee arthroplasty and a positive severe acute respiratory syndrome coronavirus 2 polymerase chain reaction test. We describe our perioperative protocol and challenges for ensuring the safety of healthcare providers while operating on a coronavirus disease 2019 (COVID-19)-positive patient.

CONCLUSIONS

Given the incredible spread of COVID-19 globally, hospitals should anticipate perioperative protocols for the surgical management of COVID-19-positive patients with concurrent pathology to ensure safety to healthcare providers.

Which Nonsurgical Treatments Do Patients Believe Are Most Effective for Hip and Knee Arthritis?

BACKGROUND

The purpose of this study was to determine which nonsurgical treatments patients believe are most effective for managing pain secondary to hip and knee arthritis.

METHODS

Five hundred sixty-five consecutive patients were administered an anonymous questionnaire developed in consultation with a center with expertise in survey design. Statistical analyses included Student t-test, Fisher Exact, Wilcoxon Rank-Sum test, and generalized cost-effectiveness analysis.

RESULTS

Four hundred thirty-six patients completed the questionnaire (response rate 77.2%). Opioids (52 of 118; 44.1%), prescription nonsteroidal anti-inflammatory drugs (NSAIDs) (67 of 200; 33.5%), and corticosteroid injections (87 of 260; 33.5%) were reported as most effective. Stem cell and platelet-rich plasma injections were selected by three of 12 (25.0%) and three of 15 patients (19.5%), respectively, and physical therapy (PT) by 50 of 257 patients (19.5%). Twenty-five percent of respondents received opioids, commonly prescribed by primary care providers (48.2%) and orthopaedic surgeons (39.5%). Opioid use correlated with lower patient-reported effectiveness of PT, NSAIDs, and corticosteroid injections (P < 0.05). The highest cost-effectiveness ratios were NSAIDs, opioids, and acetaminophen (2.2, 3.7, 4.0, and 5.4, respectively). The lowest cost-effectiveness ratios were stem cell injections, platelet-rich plasma injections, and PT (1966.7, 520.8, and 138.6, respectively).

CONCLUSIONS

The nonsurgical treatments that are reported by patients to be most effective are oftentimes the least expensive.

Superior Survivorship for Posterior Stabilized Versus Constrained Condylar Articulations After Revision Total Knee Arthroplasty: A Retrospective, Comparative Analysis at Short-Term Follow-Up

BACKGROUND

The decision to use a posterior stabilized (PS) or constrained condylar knee (CCK) articulation in revision total knee arthroplasty (RTKA) has traditionally been based on surgeon preference and knee stability. The purpose of this study is to compare various outcomes and survivorship in RTKA with PS or CCK articulations.

METHODS

A retrospective comparative study of RTKA with CCK or PS articulations (PS = 106/CCK = 147) was performed with minimum 2-year follow-up. Exclusion criteria were patients with rotating hinged implants or non-CCK/PS constructs. Multivariate logistic regression models were constructed to determine whether implant articulation influenced (1) complications, (2) aseptic loosening, and (3) re-revision. Kaplan-Meier estimates of cumulative implant survival were constructed with revision as the failure variable.

RESULTS

PS articulation was an independent predictor of increased postoperative knee flexion (6.4°, P = .010) and the knee society functional score (10.0, P = .002). Survivorship was significantly reduced for CCK revision articulations when all-cause re-revision was the primary endpoint (P = .0003, log-rank test of equality). The primary reason for re-revision in the CCK cohort was a recurrent/persistent infection of the operative knee (N = 16, 37.2%), followed by aseptic loosening (N = 13, 30.2%). PS articulations conferred a lower likelihood of re-revision (odds ratio [OR] 0.3, P = .001), but articulation design was not associated with complications (OR 0.5, P = .123) or aseptic loosening (OR 2.6, P = .143).

CONCLUSION

The PS articulation when used for appropriate indication conferred superior survivorship for the primary endpoint of all-cause re-revision and overall knee function when compared to the CCK articulation after RTKA. Implant articulation was not a predictor of aseptic loosening or complications.

Internal Validation of a Predictive Model for Satisfaction After Primary Total Knee Arthroplasty

BACKGROUND

As the number of total knee arthroplasty (TKA) procedures continues to rise in the context of bundled payment models, patients dissatisfied postoperatively that require additional care will impose additional cost to the healthcare system. The purpose of this study is to internally validate a predictive model for postoperative patient satisfaction after TKA.

METHODS

In total, 484 consecutive primary TKA patients between January 2014 and January 2016 were included. Patients were stratified into 4 risk tiers based on scores of a retrospectively applied, 11-component novel knee survey for postoperative satisfaction: low risk (>96.5), mild risk (75-96.4), moderate risk (60-74.9), and high risk (<60). Binary logistic and multivariate linear regression models were constructed to determine whether the survey was predictive of satisfaction. A receiver operator curve was constructed to determine a threshold score below which patients were likely to experience postoperative dissatisfaction.

RESULTS

The mean (±standard deviation) age was 66.3 ± 9.2 years (range 31.7-100.1) and mean body mass index was 34.2 ± 8.2 kg/m² (range 16.2-68.4). A knee survey score of 96.5 conferred a 97.5% sensitivity and 95.7% negative predictive value for satisfaction. Patients with higher knee survey scores had greater odds (odds ratio 1.03, 95% confidence interval 1.01-1.06, P = .003) of postoperative satisfaction. Increasing risk tier was significantly associated with decreased satisfaction (low risk 95.7%, mild risk 93.8%, moderate risk 86.4%, and high risk 80.4%; P = .007). The knee survey was not significantly correlated with complications (r = -0.43, P = .32).

CONCLUSION

This novel knee survey conferred a 97.5% sensitivity and 95.7% negative predictive value in identifying at-risk patients for postoperative dissatisfaction after primary TKA.

Publication rates of abstracts presented at the annual meeting of the Society of Military Orthopaedic Surgeons

Previous studies have reported publication rates of abstracts presented at orthopaedic meetings from 22 to 68 percent. The objective of this study was to determine the publication rate of papers presented at the Society of Military Orthopaedic Surgeons (SOMOS) meetings from 1999 to 2003. A database was created including all abstracts presented at SOMOS meetings from 1999 to 2003 as listed in official program books. To assess whether each abstract resulted in publication in a peer-reviewed journal, a computerized PubMed search of the presenting author and appropriate keywords from the title was conducted. Overall, 191 of the 435 abstracts presented at SOMOS from 1999 to 2003 were published in a peer-reviewed journal, giving a publication rate of 44%. The publication rate of abstract presentations at annual SOMOS meetings compares favorably with the rates for other orthopaedic meetings. However, less than 50% result in peer-reviewed publication.

Prevalence of answers to orthopaedic in-training examination questions in 3 commonly used orthopedic review sources

One of the greatest predictors for resident success on the Orthopaedic In-Training Examination (OITE) is reviewing previous OITE questions. However, no studies have examined which review sources contain the most answers to previously asked OITE questions. The goal of this study was to determine which review source contains the most answers to previously asked OITE questions. Each question from the 2006 to 2010 OITEs was examined. The questions were placed into 1 of 13 categories based on their topic. The publication date of the recommended readings associated with each question was recorded. The answer to each question was then searched for in 3 commonly used review sources: Miller's Review of Orthopaedics, 5th edition (MRO), American Academy of Orthopaedic Surgeons Comprehensive Orthopaedic Review (COR), and www.orthobullets.com (OB). Searchable electronic versions of each textbook were used, and each question had a 12-minute time limit. Of 1358 questions, 665 (49%) were found in all 3 sources. Significantly more answers were found on OB (99.4%) compared with MRO (60%) and COR (62%) (P<.0001). Significantly more answers to questions in each question category were found on OB compared with MRO or COR (P<.0001). More than 50% of all recommended readings for OITE questions were published within 5 years of the OITE. Residents using OB to review for the OITE will be exposed to significantly more answers of previously asked OITE questions than residents using MRO or COR (P<.0001).

Passive retrograde cerebral perfusion during routine cardiac valve surgery reverses middle cerebral artery blood flow and reduces the risk of stroke

BACKGROUND AND AIMS OF THE STUDY

Cerebral complications constitute a major source of morbidity and disability after cardiac valve surgery. These may be the result of macroembolization (air/debris) or inadequate perfusion pressure. In an attempt to reduce the incidence of cerebral vascular accident (CVA)/transient ischemic attack (TIA), we have routinely performed three minutes of passive retrograde cerebral perfusion (PRCP) on all valve cases. Here, we retrospectively determined our perioperative (0-30 day) incidence of CVA/TIA.

METHODS

In all cases, the extracorporeal circuit consisted of an ascending aortic cannula and either one two-stage or two single-stage venous cannulae. Three minutes of PRCP was instituted in all cases upon discontinuation of anterograde cardiopulmonary bypass (CPB) via a shunt distal to the heart/lung machine between the arterial and venous cannulae. Mean systemic blood pressure was maintained at 60 mmHg with Neo-Synephrine. Central venous pressure never exceeded 25 mmHg. In 10 cases, transcranial Doppler ultrasonography (TCD) was used to assess middle cerebral artery (MCA) blood flow. In total, 209 consecutive valve procedures with PRCP (group A) were compared with 164 consecutive valve procedures with no PRCP (group B). All data were compared using Fisher's exact probability test. The incidence of CVA/TIA was also compared with published retrospective and prospective data.

RESULTS

TCD demonstrated blood flow reversal in the MCA after a minimum of 30 s. The incidence of CVA/TIA was 0% (0/209) in group A, and 2.4% (4/165) in group B (p = 0.0386). The incidence of CVA/TIA in published retrospective data is 0.7-3.8% and 4.8-5.2% in prospective data.

CONCLUSIONS

We have demonstrated in 209 consecutive valve cases that, upon discontinuation of CPB, routine three-minute PRCP not only reversed MCA blood flow, but also reduced the incidence of neurologic events.

Lined multifocal wearers prefer progressive addition lenses

BACKGROUND

Despite reported successes with progressive addition lenses, lined multifocals remain the lens of choice for previous lined multifocal wearers.

METHODS

To explore the feasibility of switching lined multifocal wearers to PALs, in a prospective clinical trial we interviewed 265 lined multifocal wearers, prescribed a new PAL (Varilux Comfort) and then interviewed them again to compare the lens types and patient preferences.

RESULTS

PALs ranked significantly higher than lined multifocals for all questions and were preferred by 92 percent of the patients.

CONCLUSIONS

PALs should be the lens of choice for previous bifocal wearers.

Intraoperative assessment of carotid endarterectomy: a comparison of techniques

Routine intraoperative imaging of the carotid artery following carotid endarterectomy can detect defects at the site of endarterectomy that may lead to neurologic morbidity. A number of methods have been used to evaluate the completed endarterectomy. In this prospective study we compared subjective methods of assessment (hand-held, continuous-wave Doppler imaging with audible interpretation of signals) and objective methods of assessment (duplex ultrasonography with color flow and digital subtraction arteriography) with respect to their ability to detect operative abnormalities. Fifty-three carotid endarterectomies were evaluated by means of all methods of assessment. Six patients had significant abnormalities in which the vessel was reopened and the abnormality confirmed. The sensitivity and specificity for detecting abnormalities for each method are, respectively: duplex ultrasonography with color flow, 100% and 100%; digital subtraction arteriography, 66% and 95.7%; and continuous-wave Doppler imaging with audible interpretation of signals, 16% and 97.8%. There was one (1.8%) operative carotid neurologic complication during the postoperative period and follow-up (stroke due to vein patch rupture on postoperative day 2). These data suggest that an objective rather than a subjective method of assessing carotid endarterectomy is more useful in detecting operative abnormalities and that duplex ultrasonography with color flow is as useful as digital subtraction arteriography.