Can Selected Use of Cemented and Uncemented Femoral Components in a Broad Population Produce Comparable Results Following Primary Total Hip Arthroplasty for Osteoarthritis?

INTRODUCTION

Registry data have demonstrated lower rates of revision and periprosthetic fracture in select cohorts with cemented femoral fixation at primary total hip arthroplasty (THA). Whether this is true of all component designs is not known. We hypothesized that selected use of ream-and-broach, triple-tapered uncemented stem designs may provide comparable results to cemented stems.

METHODS

From 2000 to 2018, 5,809 primary THAs were performed with either a cemented (1,304) or ream-and-broach triple-tapered uncemented stem (4,505). Implant choice was at surgeon discretion. The cemented group was older, more often women, and had slightly lower body mass index. A subgroup analysis was performed on patients ≥75-years of age. Statistical weighting accounted for baseline cohort differences.

RESULTS

At 10 years, there was a trend toward higher all-cause revision (Hazards ratio (HR) 1.6, P=0.053) and higher all-cause reoperation (HR 1.6, P=0.02) in the cemented fixation cohort. The cemented fixation group had fewer intraoperative periprosthetic fractures (HR 0.21, P<0.001), but no difference in postoperative fractures (HR 0.99, P=0.96). The same was true in patients ≥75-years. In the ≥75-years subgroup, there was no difference in revision or reoperation at 10 years.

CONCLUSION

Compared to cemented stems, the use of ream-and-broach triple-tapered uncemented stems in select patients, including those ≥75-years, was associated with more intraoperative fractures, but no difference in 10-year implant survivorship. These findings are different than some registry data and suggest that specific uncemented components, implanted in selected patients by experienced surgeons, can perform as well as cemented implants in a broad patient population.

Comparative Survival of Contemporary Cementless Acetabular Components Following Revision Total Hip Arthroplasty

BACKGROUND

The advent of highly porous ingrowth surfaces and highly crosslinked polyethylene (HXLPE) has been expected to improve implant survivorship in revision total hip arthroplasty (THA). Therefore, we sought to evaluate the survival of several contemporary acetabular designs following revision THA.

METHODS

Acetabular revisions performed from 2000 to 2019 were identified from our institutional total joint registry. We studied 3,348 revision hips, implanted with one of 7 cementless acetabular designs. These were paired with HXLPE or dual-mobility liners. A historical series of 258 Harris-Galante-1 (HG-1) components, paired with conventional polyethylene, was used as reference. Survivorship analyses were performed. For the 2,976 hips with minimum 2-year follow-up, the median follow-up was 8 years (range, 2 to 35 years).

RESULTS

Contemporary components with adequate follow-up had survivorship free of acetabular re-revision of ≥95% at 10-year follow-up. Relative to HG-1 components, 10-year survivorship free of all-cause acetabular cup re-revision was significantly higher in Zimmer TM Revision (Hazard Ratio (HR) 0.3, 95% Confidence Interval (CI) 0.2-0.45), Zimmer TM Modular (HR 0.34, 95%CI 0.13-0.89), Zimmer Trilogy (HR 0.4, 95%CI 0.24-0.69), Depuy Pinnacle Porocoat (HR 0.24, 95%CI 0.11-0.51), and Stryker Tritanium Revision (HR 0.46, 95%CI 0.24-0.91) shells. Among contemporary components, there were only 23 re-revisions for acetabular aseptic loosening and no re-revisions for polyethylene wear.

CONCLUSIONS

Contemporary acetabular ingrowth and bearing surfaces were associated with no re-revisions for wear and aseptic loosening was uncommon, particularly with highly porous designs. Therefore, it appears that contemporary revision acetabular components have dramatically improved upon historical results at available follow-up.

A Multisite Assessment of Inpatient Safety Event Rates During the Coronavirus Disease 2019 Pandemic

To date, there has been a notable lack of peer-reviewed or publicly available data documenting rates of hospital quality outcomes and patient safety events during the coronavirus disease 2019 pandemic era. The dearth of evidence is perhaps related to the US health care system triaging resources toward patient care and away from reporting and research and also reflects that data used in publicly reported hospital quality rankings and ratings typically lag 2-5 years. At our institution, a learning health system assessment is underway to evaluate how patient safety was affected by the pandemic. Here we share and discuss early findings, noting the limitations of self-reported safety event reporting, and suggest the need for further widespread investigations at other US hospitals. During the 2-year study period from January 1, 2020, through December 31, 2021 across 3 large US academic medical centers at our institution, we documented an overall rate of 25.8 safety events per 1000 inpatient days. The rate of events meeting "harm" criteria was 12.4 per 1000 inpatient days, the rate of nonharm events was 11.1 per 1000 inpatient days, and the fall rate was 2.3 per 1000 inpatient days. This descriptive exploratory analysis suggests that patient safety event rates at our institution did not increase over the course of the pandemic. However, increasing health care worker absences were nonlinearly and strongly associated with patient safety event rates, which raises questions regarding the mechanisms by which patient safety event rates may be affected by staff absences during pandemic peaks.

Collarless Taper Slip and Collared Composite Beam Stems Differ in Failure Modes and Reoperation Rates

BACKGROUND

Cemented femoral components are used in older patients based on lower risk of periprosthetic fracture and implant loosening. This study reports the survivorship free of periprosthetic femoral fracture (PPFX), femoral loosening, all-cause revision, and reoperation between 2 philosophies of cemented stems.

METHODS

In total, 1,306 primary hybrid total hip arthroplasties were performed for osteoarthritis between 2000 and 2018 in a retrospective single center study. Cemented stems included 798 EON composite beam (CB) and 508 Exeter collarless taper slip (CTS) stems. Mean age was 77 years. An inverse treated probability weighted model was utilized to control for risk factors including age, gender, body mass index, year, and surgeon.

RESULTS

There was no difference in risk of PPFX at 10 years (CTS 9% vs CB 5%; hazard ratio [HR] 1.4, P = .47). There was an increased risk of intraoperative fractures requiring fixation in the CB cohort (7/798 [5 calcar, 2 greater trochanter] vs 0/508, P < .001), while there was an increased risk of Vancouver B₂ PPFX in the CTS cohort (7/508 vs 0/798; P < 001). There was a higher risk of femoral loosening in the CB cohort (6/798 vs 0/508; P < .0001). Higher survivorship free of revision (98% vs 91%; HR 4, P = .001) and free of reoperation (96% vs 88%; HR 2.5, P = .002) was seen at 10 years in the CB cohort.

CONCLUSION

The risk of PPFX requiring implant revision was increased in the CTS cohort, while there was an increased risk of femoral component loosening and intraoperative fractures seen in the CB cohort. Surgeons should be aware of the different failure modes when choosing implant design for their patient.

Midterm Results of Primary Exeter Cemented Stem in a Select Patient Population

BACKGROUND

Most North American surgeons predominantly use uncemented stems in primary total hip arthroplasties (THAs) and reserve cemented stems for selected older patients and those with poor bone quality. However, data on this "selective use" strategy for cemented stems in the population at risk for periprosthetic fracture and implant loosening are limited. The purpose of this study was to describe implant survivorship, complications, and radiographic results of a specific collarless, polished, tapered cemented stem (Exeter; Stryker) used selectively in a predominantly elderly population undergoing primary THA.

METHODS

We identified 386 patients who underwent a total of 423 primary THAs with selectively utilized Exeter stems for the treatment of osteoarthritis between 2006 and 2017. In the same time period, 11,010 primary THAs were performed with uncemented stems and 961 with non-Exeter cemented stems. The mean patient age was 77 years, 71% were female, and the mean body mass index was 29 kg/m2. Competing risk analysis accounting for death was utilized to determine cumulative incidences of revision and reoperation. The mean follow-up was 5 years (range, 2 to 12 years).

RESULTS

The 10-year cumulative incidence of any femoral component revision in this patient cohort was 4%, with 10 stems revised at the time of the latest follow-up. There were no intraoperative femoral fractures. The indications for revision were postoperative periprosthetic femoral fracture (n = 6), dislocation (n = 3), and infection (n = 1). There were no revisions for femoral loosening. The 10-year cumulative incidence of reoperation was 10%. The 10-year cumulative incidence of Vancouver B periprosthetic femoral fracture was 2%. Radiographically, there were no cases of aseptic loosening or osteolysis. There was a significant improvement in median Harris hip score, from 53 preoperatively to 92 at a mean follow-up of 5 years (p < 0.001).

CONCLUSIONS

The strategy of selectively utilizing a collarless, polished, tapered cemented stem produced a low (4%) cumulative incidence of stem revision at 10 years postoperatively and resulted in no cases of aseptic loosening. The use of the Exeter stem did not eliminate postoperative femoral fractures in this predominantly elderly, female patient population.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Low-Dose vs Regular-Dose Aspirin for Venous Thromboembolism Prophylaxis in Primary Total Joint Arthroplasty

BACKGROUND

Consensus on whether low-dose (81 mg) or regular-dose (325 mg) aspirin (ASA) is more effective for venous thromboembolism (VTE) chemoprophylaxis in primary total joint arthroplasties (TJAs) is not reached. The goal of this study is to evaluate the efficacy of low-dose and regular-dose ASA for VTE chemoprophylaxis in primary total hip arthroplasties and total knee arthroplasties.

METHODS

We retrospectively identified 3512 primary TJAs (2344 total hip arthroplasties and 1168 total knee arthroplasties) with ASA used as VTE chemoprophylaxis between 2000 and 2019. Patients received ASA twice daily for 4-6 weeks after surgery with 961 (27%) receiving low-dose ASA and 2551 (73%) receiving regular-dose ASA. The primary endpoint was 90-day incidence of symptomatic VTEs. Secondary outcomes were gastrointestinal (GI) bleeding events and mortality. The mean age at index TJA was 66 years, 54% were female, and mean body mass index was 31 kg/m². The mean Charlson Comorbidity Index was 3.5. Mean follow-up was 3 years.

RESULTS

There was no difference in 90-day incidence of symptomatic VTEs between low-dose and regular-dose ASA (0% vs 0.1%, respectively; P = .79). There were no GI bleeding events in either group. There was no difference in 90-day mortality between low-dose and regular-dose ASA (0.3% vs 0.1%, respectively; P = .24).

CONCLUSION

In 3512 primary TJA patients treated with ASA, we found a cumulative incidence of VTE <1% at 90 days. Although this study is underpowered, it appears that twice daily low-dose ASA was equally effective to twice daily regular-dose ASA for VTE chemoprophylaxis, with no difference in risk of GI bleeds or mortality.

LEVEL OF EVIDENCE

III, retrospective cohort study.

Total Hip Arthroplasty in Patients With Osteopetrosis

BACKGROUND

Osteopetrosis is an inherited bone disease associated with high risk of osteoarthritis and fracture non-union, which can lead to total hip arthroplasty (THA). Bone quality and morphology are altered in these patients, and there are limited data on results of THA in these patients. The goals of this study were to describe implant survivorship, clinical outcomes, radiographic results, and complications in patients with osteopetrosis undergoing primary THA.

METHODS

We identified 7 patients (9 hips) with osteopetrosis who underwent primary THA between 1970 and 2017 utilizing our total joint registry. The mean age at index THA was 48 years and included two males and five females. The mean follow-up was 8 years.

RESULTS

The 10-year survivorship free from any revision or implant removal was 89%, with 1 revision and 1 resection arthroplasty secondary to periprosthetic femoral fractures. The 10-year survivorship free from any reoperation was 42%, with 4 additional reoperations (2 ORIFs for periprosthetic femoral fractures, 1 sciatic nerve palsy lysis of adhesions, 1 hematoma evacuation). Harris hip scores significantly increased at 5 years (P = .04). Five hips had an intraoperative acetabular fracture, and 1 had an intraoperative femur fracture. All postoperative femoral fractures occurred in patients with intramedullary diameter less than 5 mm at a level 10 cm distal to the lesser trochanter.

CONCLUSION

Primary THA in patients with osteopetrosis is associated with good 10-year implant survivorship (89%), but a very high reoperation (58%) and periprosthetic femoral fracture rate (44%). Femoral fractures appear associated with smaller intramedullary diameters.

Orthopedic Surgery and Anesthesiology Surgical Improvement Strategies Project: Phase I Outcomes

BACKGROUND

This study aimed to improve institutional value-based patient care processes, provider collaboration, and continuous process improvement mechanisms for primary total hip arthroplasties and total knee arthroplasties through establishment of a perioperative orthopedic surgical home.

METHODS

On June 1, 2017, an institutionally sponsored initiative commenced known as the orthopedic surgery and anesthesiology surgical improvement strategy project. A multidisciplinary team consisting of orthopedic surgeons, anesthesiologists, advanced practice providers, nurses, pharmacists, physical therapists, social workers, and hospital administration met regularly to identify areas for improvement in the preoperative, intraoperative, and post-anesthesia care unit, and postoperative phases of care.

RESULTS

Mean hospital length of stay decreased from 2.7 to 2.2 days (P < .001), incidence of discharge to a skilled nursing facility decreased from 24% to 17% (P = .008), and the number of patients receiving physical therapy on the day of surgery increased from 10% to 100% (P < .001). Press-Ganey scores increased from 74.9 to 75.8 (94th percentile), while mean and maximum pain scores, opioid consumption, and hospital readmission rates remained unchanged (lowest P = .29). Annual total hip arthroplasty and total knee arthroplasty surgical volume increased by 11.4%. Decreased hospital length of stay and increased surgical volume yielded a combined annual savings of $2.5 million across the 9 involved orthopedic surgeons.

CONCLUSION

Through application of perioperative surgical home tools and concepts, key advances included phase of care integration, enhanced data management, decreased length of stay, coordinated perioperative management, increased surgical volume without personnel additions, and more efficient communication and patient care flow across preoperative, intraoperative, and postoperative phases.

LEVEL OF EVIDENCE

III Therapeutic.

Contemporary Primary Total Knee Arthroplasty is Durable in Patients Diagnosed With Ankylosing Spondylitis

INTRODUCTION

Ankylosing spondylitis (AS) is a seronegative spondyloarthropathy affecting the axial spine and peripheral joints. Despite innovations in medical management, patients with AS experience two-fold the lifetime risk of total knee arthroplasty (TKA) compared to the general population. Moreover, recent data have indicated a correlation between spinal pathology and outcomes of TKAs.

METHODS

Our institutional total joint registry identified 19 patients (28 knees) with a diagnosis of AS treated with primary TKA from 2000 to 2016. The mean age at TKA was 68 years, and 84% of patients were men. The mean follow-up period was 6 years. Outcomes included implant survivorship, clinical outcomes, and complications.

RESULTS

Survivorship free from any revision was 88% at 10 years. A single patient required revision at 8 years for aseptic loosening. Survivorship free from any reoperation was 77% at 10 years. Reoperations included 2 manipulations under anesthesia and 1 superficial wound irrigation and debridement. Mean Knee Society score improved from 46 preoperatively to 89 postoperatively (P < .0001). The mean arc of motion improved from 108^o preoperatively to 116° postoperatively (P = .01). There were 6 complications that did not require reoperation.

CONCLUSION

Primary TKAs in patients with AS resulted in significant improvement in clinical outcomes with excellent 10-year implant survivorship. Although 2 manipulations under anesthesia were required, the range of motion was restored postoperatively. These data suggest that the contemporary primary TKA can achieve durable and reliable outcomes in patients with axial skeletal disease resulting from AS.

LEVEL OF EVIDENCE

IV.

Two-stage arthrodesis for complex, failed, infected total knee arthroplasty

AIMS

Arthrodesis is rarely used as a salvage procedure for patients with a chronically infected total knee arthroplasty (TKA), and little information is available about the outcome. The aim of this study was to assess the reliability, durability, and safety of this procedure as the definitive treatment for complex, chronically infected TKA, in a current series of patients.

METHODS

We retrospectively identified 41 patients (41 TKAs) with a complex infected TKA, who were treated between 2002 and 2016 using a deliberate, two-stage knee arthrodesis. Their mean age was 64 years (34 to 88) and their mean body mass index (BMI) was 39 kg/m² (25 to 79). The mean follow-up was four years (2 to 9). The extensor mechanism (EM) was deficient in 27 patients (66%) and flap cover was required in 14 (34%). Most patients were host grade B (56%) or C (29%), and limb grade 3 (71%), according to the classification of McPherson et al. A total of 12 patients (29%) had polymicrobial infections and 20 (49%) had multi-drug resistant organisms; fixation involved an intramedullary nail in 25 (61%), an external fixator in ten (24%), and dual plates in six (15%).

RESULTS

Survivorship free from amputation, persistent infection, and reoperation, other than removal of an external fixator, at five years was 95% (95% confidence interval (CI) 89% to 100%), 85% (95% CI 75% to 95%), and 64% (95% CI 46% to 82%), respectively. Reoperation, other than removal of an external fixator, occurred in 13 patients (32%). After the initial treatment, radiological nonunion developed in ten knees (24%). Nonunion was significantly correlated with persistent infection (p = 0.006) and external fixation (p = 0.005). Of those patients who achieved limb salvage, 34 (87%) remained mobile and 31 (79%) had 'absent' or 'minimal' pain ratings.

CONCLUSION

Knee arthrodesis using a two-stage protocol achieved a survivorship free from amputation for persistent infection of 95% at five years with 87% of patients were mobile at final follow-up. However, early reoperation was common (32%). This is not surprising as this series included worst-case infected TKAs in which two-thirds of the patients had a disrupted EM, one-third required flap cover, and most had polymicrobial or multi-drug resistant organisms. Cite this article: Bone Joint J 2020;102-B(6 Supple A):170-175.

Implementation of Procedure-Specific Opioid Guidelines: A Readily Employable Strategy to Improve Consistency and Decrease Excessive Prescribing Following Orthopaedic Surgery

Background:

Evidence-based, procedure-specific guidelines for prescribing opioids are urgently needed to optimize pain relief while minimizing excessive opioid prescribing and potential opioid diversion in our communities. A multidisciplinary panel at our institution recently developed procedure-specific guidelines for discharge opioid prescriptions for common orthopaedic surgical procedures. The purpose of this study was to evaluate postoperative opioid prescription quantities, variability, and 30-day refill rates before and after implementation of the guidelines.

Methods:

This retrospective cohort study was conducted at a single academic institution from December 2016 to March 2018. Guidelines were implemented on August 1, 2017, with a recommended maximum opioid prescription quantity for 14 common orthopaedic procedures. Patients who underwent these 14 procedures during the period of December 2016 to May 2017 made up the pre-guideline cohort (n = 2,223), and patients who underwent these procedures from October 2017 to March 2018 made up the post-guideline cohort (n = 2,300). Opioid prescription quantities were reported as oral morphine equivalents (OME), with medians and interquartile ranges (IQRs). Four levels were established for recommended prescription maximums, ranging from 100 to 400 OME.

Results:

In the pre-guideline cohort, the median amount of prescribed opioids across all procedures was 600 OME (IQR, 390 to 863 OME), which decreased by 38% in the post-guideline period, to a median of 375 OME (IQR, 239 to 400 OME) in the post-guideline cohort (p < 0.001). The 30-day refill rate did not change significantly, from a rate of 24% in the pre-guideline cohort to 25% in the post-guideline cohort (p = 0.43). Multivariable analysis demonstrated that guideline implementation was the factor most strongly associated with prescriptions exceeding guideline maximums (odds ratio [OR] = 9.9; p < 0.001). Age groups of <80 years (OR = 2.0 to 2.4; p < 0.001) and males (OR = 1.2; p = 0.025) were also shown to have higher odds of exceeding guideline maximums.

Conclusions:

Procedure-specific guidelines are capable of substantially decreasing opioid prescription amounts and variability. Furthermore, the absence of change in refill rates suggests that pain control remains similar to pre-guideline prescribing practices. Evidence-based guidelines are a readily employable solution that can drive rapid change in practice and enhance the ability of orthopaedic surgeons to provide responsible pain management.

Povidone-Iodine Wound Lavage to Prevent Infection After Revision Total Hip and Knee Arthroplasty: An Analysis of 2,884 Cases

BACKGROUND

Postoperative infection remains a major challenge in revision total hip arthroplasty (THA) and revision total knee arthroplasty (TKA). Wound irrigation with dilute povidone-iodine (PI) solution has emerged as a simple, inexpensive, and potentially successful means of reducing postoperative infections. The aim of this study was to assess its effectiveness in reducing infection following revision THA and TKA in, to our knowledge, the largest revision cohort to date.

METHODS

Using our institution's total joint registry, we identified 1,402 revision THAs and 1,482 revision TKAs performed during the study period (2013, when the PI irrigation protocol was first implemented, to 2017). The PI lavage protocol was employed in 27% of the revision THA cases and 34% of the revision TKA cases; in the remaining cases, the protocol was not used. Demographics, comorbid conditions, underlying surgical diagnoses, and whether the revision was for a septic or an aseptic etiology were compared between the groups (use or no use of PI irrigation). Any reoperation due to infection, as assessed at 3 and 12 months following revision arthroplasty, was compared between the groups and propensity scores were calculated to account for differences in baseline characteristics between the groups.

RESULTS

After adjusting for baseline differences between the groups using the propensity-score weighted models, we found no significant difference in the rate of reoperation for infection at 3 months (p = 0.58 for revision THA, and p = 0.06 for revision TKA) and at 12 months (p = 0.78 for revision THA, and p = 0.06 for revision TKA). Nonetheless, the hazard ratios from the propensity-score model trended higher for patients who received PI lavage: 1.6 and 1.3 for revision THA at 3 and 12 months, respectively, and 2.9 at both 3 and 12 months for revision TKA.

CONCLUSIONS

PI wound lavage demonstrated no benefit in reducing any reoperation for infection following revision THA and TKA. Moreover, the trend toward higher rates for reoperation for infection among patients who received PI irrigation merit further consideration.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Use of Povidone-Iodine Irrigation Prior to Wound Closure in Primary Total Hip and Knee Arthroplasty: An Analysis of 11,738 Cases

BACKGROUND

Povidone-iodine (PI) irrigation is often used prior to wound closure in total joint arthroplasty, but there are limited reports evaluating its efficacy in decreasing joint infections. The goal of this study was to compare the rate of any reoperation for infection (both superficial and deep) in primary total hip arthroplasty (THA) and primary total knee arthroplasty (TKA) among patients who did and did not receive PI irrigation prior to wound closure.

METHODS

Using our institution's total joint registry, we identified 5,534 primary THA and 6,204 primary TKA procedures performed from 2013 to 2017. Cases were grouped on the basis of whether or not the wound was irrigated with 1 L of 0.25% PI prior to closure. PI irrigation was used in 1,322 (24%) of the THA cases and in 2,410 (39%) of the TKA cases. The rates of reoperation for infection at 3 months and 1 year were compared between the 2 groups. The same comparisons were then performed using propensity scores to account for differences in baseline characteristics.

RESULTS

The rate of reoperation for infection as assessed at 3 months following THA was similar between those who received dilute PI irrigation (0.9%) and who did not (0.7%) (p = 0.7). At 1 year, the rate of reoperation for infection was similar between those who received dilute PI irrigation (0.7%) and those who did not (0.9%) (p = 0.6). After using the propensity score, there was no difference between the groups in the risk of septic reoperations. For TKA, the rate of reoperation as assessed at 3 months was similar between those who received dilute PI irrigation (0.8%) and those who did not (0.3%) (p = 0.06). At 1 year, there was a greater rate of reoperations for infection among those who received dilute PI irrigation (1.2%) compared with those who did not (0.6%) (p = 0.03). However, there was no difference in the risk of septic reoperations between the groups after using the propensity score.

CONCLUSIONS

Despite enthusiasm for and progressive adoption of the use of dilute PI irrigation at our institution, there was not a significant reduction in the risk of reoperation for infection as assessed at 3 months and 1 year following primary THA and TKA.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Smoking Cessation Before and After Total Joint Arthroplasty-An Uphill Battle

BACKGROUND

Patients actively smoking at the time of primary total joint arthroplasty (TJA) are at increased risk of perioperative complications. Employing strategies for smoking cessation has therefore become routine. A potential benefit of cessation in anticipation of TJA may be long-term cessation. However, success rates and the longevity of successful smoking cessation attempts before TJA have yet to be presented.

METHODS

Our institution's total joint registry documents self-reported smoking status. As such, all patients who underwent TJA from 2007 to 2018 were identified and grouped as nonsmokers, smokers (regularly smoking within 1 year before surgery), and former smokers (those who quit smoking within 1 year before surgery). Thereafter, postoperative smoking status was assessed with special attention to former smokers to see who remained smoke-free.

RESULTS

From the 28,758 primary TJAs identified, 91.3% (26,244) were nonsmokers, 7.3% (2109) were smokers, and 1.4% (405) had quit smoking before surgery. Among former smokers, 86% were abstinent 1 year postoperatively but only 45% were still abstinent 8 years postoperatively. Conversely, 7% of smokers at the time of surgery eventually quit and 6% of prior nonsmokers started smoking over the same time period.

CONCLUSION

Despite concerted efforts to help patients stop smoking before TJA, 7.3% remain smokers. Among those who are successful, less than half (45%) remain smoke-free after surgery. Compared to current smokers, however, patients who managed to quit before surgery are more likely to remain smoke-free after surgery. These findings demonstrate the tremendous challenge smoking represents in contemporary TJA practices.

LEVEL OF EVIDENCE

Therapeutic level III.

Cotinine Testing Improves Smoking Cessation Before Total Joint Arthroplasty

BACKGROUND

Patients who are actively smoking at the time of primary total joint arthroplasty (TJA) are at an increased risk of perioperative complications. Serum cotinine testing is a sensitive and specific method to verify abstinence from smoking and may therefore improve a patient's chance of smoking cessation. The primary purpose of this study was to assess whether cotinine testing improves the self-reported quit rate among smokers before TJA.

METHODS

Our hospital performs a high volume of TJAs and documents smoking status at each clinic visit (at 6-month intervals), as well as at the time of surgery through an institutional total joint registry. As part of a retrospective analysis, this information was used to identify all self-reported smokers (regularly cigarette smoking within 1 year of TJA) who underwent unilateral TJA from 2007 to 2018. The cohort had a mean age of 66 years, 55% were female, and the mean body mass index was 31 kg/m². Patients whose serum cotinine was obtained within 1 month before surgery were then separated from the cohort and compared to the smokers who did not undergo cotinine testing.

RESULTS

Of the 28,758 primary TJAs identified, 8.8% (2514) were smokers. Serum cotinine testing was obtained on 103 of these patients. The abstinence rate (by means of self-reporting) before surgery significantly improved from 15.8% to 28.2% in the untested vs cotinine-tested groups, respectively (P = .005). Among all patients who underwent cotinine testing, 77% were negative (abstinent) and an additional 15% had cotinine levels between 3 and 8 ng/mL representing passive tobacco exposure. Among patients who stated they had quit smoking, 15% still had positive cotinine tests.

CONCLUSION

Smoking cessation remains a major challenge in contemporary TJA practices despite a concerted effort to help patients quit. Our findings suggest that cotinine testing significantly improves the self-reported quit rates of smokers before surgery and helps identify the 15% who falsely report abstinence to ensure appropriate counseling of inherent risks.

LEVEL OF EVIDENCE

Therapeutic level III.

Cost and Patient Outcomes Associated With Bilateral Total Knee Arthroplasty Performed by 2-Surgeon Teams vs a Single Surgeon

BACKGROUND

Bilateral total knee arthroplasty (TKA) can be performed under a single-anesthetic (SA) or staged under a two-anesthetic (TA) technique. Recently, our institution began piloting a 2-surgeon team SA method for bilateral TKA. The purpose of this study was to compare the inpatient costs and clinical outcomes in the first 90 days after surgery between the team SA, single-surgeon SA, and single-surgeon TA approaches for bilateral TKA.

METHODS

All primary TKAs performed from 2007 to 2017 by the 2 participating surgeons for each of the 3 groups of interest were identified: team SA (N = 42 patients; 84 knees), single-surgeon SA (N = 146 patients; 292 knees), single-surgeon TA (N = 242 patients; 484 knees). No patients were lost to follow-up.

RESULTS

Median hospital cost (per TKA) for the episode(s) of care was as follows: team SA $20,962, single-surgeon SA $22,057, single-surgeon TA $31,145 (P < .001 overall; P = .0905 team SA vs single-surgeon SA). Rate of 90-day complications was 2.4% for team SA, 11.0% for single-surgeon SA, and 8.3% for single-surgeon TA (P = .2090). Discharge to skilled nursing facilities or rehab was as follows: team SA 31%, single-surgeon SA 53%, and single-surgeon TA after the second operation 34% (P < .001).

CONCLUSION

This pilot project suggests that team SA bilateral TKA is a potentially cost-effective option with fewer complications compared to single-surgeon SA bilateral TKA. The less frequent disposition to skilled nursing facilities in the team SA group in conjunction with more efficient operating room utilization may further enhance the financial benefits.

Geniculate Artery Injury During Primary Total Knee Arthroplasty

Major arterial injury associated with total knee arthroplasty (TKA) is a rare and potentially devastating complication. However, the rate of injury to smaller periarticular vessels and the clinical significance of such an injury have not been well investigated. The purpose of this study is to describe the rate and outcomes of geniculate artery (GA) injury, the time at which injury occurs, and any associations with tourniquet use. From November 2015 to February 2016, 3 surgeons at a single institution performed 100 consecutive primary TKAs and documented the presence or absence and the timing of GA injury. The data were then retrospectively reviewed. All TKAs had no prior surgery on the operative extremity. Other variables collected included tourniquet use, tranexamic acid (TXA) administration, intraoperative blood loss, postoperative drain output, and blood transfusion. The overall rate of GA injury was 38%, with lateral inferior and middle GA injury in 31% and 15% of TKAs, respectively. Most of the injuries were visualized during bone cuts or meniscectomy. The rate of overall or isolated GA injury was not significantly different (P > .05) with either use of intravenous (84 patients) or topical (14 patients) TXA administration. Comparing selective tourniquet use (only during cementation) vs routine use showed no differences in GA injury rate (P = .37), blood loss (P = .07), or drain output (P = .46). There is a relatively high rate of GA injury, with injury to the lateral GA occurring more often than the middle GA. Routine or selective tourniquet use does not affect the rate of injury.

Two-Stage Exchange Protocol for Periprosthetic Joint Infection Following Total Knee Arthroplasty in 245 Knees without Prior Treatment for Infection

BACKGROUND

For patients undergoing 2-stage exchange for the treatment of periprosthetic joint infection (PJI) following total knee arthroplasty, the long-term risk of reinfection and mechanical failure and long-term clinical outcomes are not well known. The purpose of our study was to determine the long-term clinical results of 2-stage exchange for PJI following total knee arthroplasty.

METHODS

We identified 245 knees that had undergone total knee arthroplasty and were subsequently treated with 2-stage exchange due to infection during the period of 1991 to 2006; the cohort had no prior treatment for PJI. Major, or 4 of 6 minor, Musculoskeletal Infection Society (MSIS) diagnostic criteria were fulfilled by 179 (73%) of the knees. The cumulative incidence of reinfection and of aseptic revision, accounting for the competing risk of death, were calculated. Risk factors for reinfection were evaluated using Cox proportional hazards regression. Knee Society Score (KSS) values were calculated. The mean age at spacer insertion was 68 years; 50% of the patients were female. The mean follow-up was 14 years (range, 2 to 25 years) following reimplantation.

RESULTS

The cumulative incidence of reinfection was 4% at 1 year, 14% at 5 years, 16% at 10 years, and 17% at 15 years. Factors that were predictive of reinfection included a body mass index of ≥30 kg/m (hazard ratio [HR], 3.1; p < 0.01), previous revision surgery (HR, 2.8; p < 0.01), and a McPherson host grade of C (HR, 2.5; p = 0.04). The cumulative incidence of aseptic revision for loosening was 2% at 5 years, 5% at 10 years, and 7% at 15 years. Femoral (HR, 5.0; p = 0.04) and tibial (HR, 6.7; p < 0.01) bone-grafting at reimplantation were predictive of aseptic failure. The most common complications were wound-healing issues, requiring reoperation in 12 (5%) of the knees. The rate of death at 2 years following reimplantation was 11%. The mean KSS improved from 45 at PJI diagnosis to 76 at 10 years following reimplantation (p < 0.01).

CONCLUSIONS

Long-term reinfection rates following 2-stage exchange for PJI after total knee arthroplasty were similar to those of shorter-term reports and were maintained out to 15 years. Mechanical failure rates were low if bone loss was addressed at the time of reimplantation. Improvements in clinical outcomes were maintained at long-term follow-up.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Long-Term Results of a 2-Stage Exchange Protocol for Periprosthetic Joint Infection Following Total Hip Arthroplasty in 164 Hips

BACKGROUND

Limited data exist that show the long-term risks of reinfection and mechanical failure with a contemporary 2-stage exchange protocol for periprosthetic joint infection following total hip arthroplasty. The purpose of this study was to determine the long-term reinfection and mechanical failure rates of 2-stage exchange for periprosthetic joint infection after total hip arthroplasty.

METHODS

We identified 164 hips (162 patients) with infection after total hip arthroplasty between 1991 and 2006 treated with a 2-stage exchange protocol with no prior treatment for periprosthetic joint infection. With regard to Musculoskeletal Infection Society diagnostic criteria, at least 1 major criterion or 4 of 6 minor criteria were fulfilled in 129 hips (79%). The cumulative incidence with a competing risk of death was calculated for reinfection, aseptic revisions, and all-cause revisions. The risk factors for reinfection were evaluated using Cox proportional hazards regression. Harris hip scores were calculated. The mean age at the time of spacer insertion was 68 years, and 35% of the patients were female. Excluding the patients with <2 years of follow-up, the mean follow-up was 12 years (range, 2 to 21 years).

RESULTS

The cumulative incidence of recurrence of infection was 10% at 1 year, 14% at 5 years, and 15% at 10 and 15 years. Seventeen patients (11%) used chronic antibiotic suppression (>6 months), with 7 (41%) of these having recurrent infection at the time of the latest follow-up. Use of chronic antibiotic suppression was the only predictive factor for reinfection (hazard ratio, 4.5 [95% confidence interval (CI), 1.9 to 10.9]; p = 0.001). The cumulative incidence of aseptic femoral and acetabular revisions was 2.6% at 5 years and 3.3% at 10 and 15 years. The cumulative incidence of all-cause revisions was 15% at 5 years and 16% at 10 and 15 years. Dislocation was the most common complication, with 28 dislocations occurring in 20 patients (12%). The mean Harris hip score improved from 52 points prior to spacer insertion to 70 points at 15 years after reimplantation (p < 0.01).

CONCLUSIONS

The rate of recurrence of infection of 15% for up to 15 years after total hip arthroplasty was similar to previous shorter-term reports of 2-stage exchange for periprosthetic joint infection. Surgeons should anticipate mitigating instability after reimplantation. Implant survivorship free of aseptic loosening and clinical outcomes were preserved for the long term. The role of chronic antibiotic suppression in the long-term treatment of periprosthetic joint infection requires further investigation.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The 2018 Chitranjan S. Ranawat, MD Award: Developing and Implementing a Novel Institutional Guideline Strategy Reduced Postoperative Opioid Prescribing After TKA and THA

BACKGROUND

Opioid prescription management is challenging for orthopaedic surgeons, and we lack evidence-based guidelines for responsible opioid prescribing. Our institution recently developed opioid prescription guidelines for patients undergoing several common orthopaedic procedures including TKA and THA in an effort to reduce and standardize prescribing patterns.

QUESTIONS/PURPOSES

(1) How do opioid prescriptions at discharge and 30-day refill rates change in opioid-naïve patients undergoing primary TKA and THA before and after implementation of a novel prescribing guideline strategy? (2) What patient, surgical, and in-hospital factors influence opioid prescription quantity and refill rate?

METHODS

New institutional guidelines for patients undergoing TKA and THA recommend a maximum postoperative prescription of 400 oral morphine equivalents (OME), comparable to 50 tablets of 5 mg oxycodone or 80 tablets of 50 mg tramadol. All opioid-naïve patients, defined as those who did not take any opioids within 90 days preceding surgery, undergoing primary TKA and THA at a single tertiary care institution were evaluated from program initiation on August 1, 2017, through December 31, 2017, as the postguideline era cohort. This group (n = 751 patients) was compared with all opioid-naïve patients undergoing TKA and THA from 2016 at the same institution (n = 1822 patients). Some providers were early adopters of the guidelines as they were being developed, which is why January to July 2017 was not evaluated. Patients in the preguideline and postguideline eras were not different in terms of age, sex, race, body mass index, education level, employment status, psychiatric illness, marital status, smoking history, outpatient use of benzodiazepines or gabapentinoids, or diagnoses of diabetes mellitus, peripheral neuropathy, or cancer. The primary outcome assessed was adherence to the new guidelines with a secondary outcome of opioid medication refills ordered within 30 days from any provider. Multivariable logistic regression analyses were performed with outcomes of guideline compliance and refills and adjusted for demographic, surgical, and patient care factors. Patients were followed for 30 days after surgery and no patients were lost to followup.

RESULTS

Median opioid prescription and range of prescriptions decreased in the postguideline era compared with the preguideline era (750 OME, interquartile range [IQR] 575-900 OME versus 388 OME, IQR 350-389; difference of medians = 362 OME; p < 0.001). There was no difference among patients undergoing TKA before and after guideline implementation in terms of the 30-day refill rate (35% [349 of 1011] versus 35% [141 of 399]; p = 0.77); this relationship was similar among patient undergoing THA (16% [129 of 811] versus 17% [61 of 352]; p = 0.55). After controlling for relevant patient-level factors, we found that implementation of an institutional guideline was the strongest factor associated with a prescription of ≤ 400 OME (adjusted odds ratio, 36; 95% confidence interval, 25-52; p < 0.001); although a number of patient-level factors also were associated with prescription quantity, the effect sizes were much smaller.

CONCLUSIONS

This study provides a proof of concept that institutional guidelines to reduce postoperative opioid prescribing can improve aftercare in patients undergoing arthroplasty in a short period of time. The current report evaluates our experience with the first 5 months of this program; therefore, longer term data will be mandatory to determine longitudinal guideline adherence and whether the cutoffs established by this pilot initiative require further refinement for individual procedures.

LEVEL OF EVIDENCE

Level II, therapeutic study.

Repeat two-stage exchange arthroplasty for prosthetic hip re-infection

Aims

Recurrent infection following two-stage revision total hip arthroplasty (THA) for prosthetic joint infection (PJI) is a devastating complication. The purpose of this study was to report the survival of repeat two-stage revision hip arthroplasty, describe complications, and identify risk factors for failure.

Patients and Methods

We retrospectively identified 19 hips (19 patients) that had undergone repeat two-stage revision THA for infection between 2000 to 2013. There were seven female patients (37%) and the mean age was 60 years (30 to 85). Survival free from revision was assessed via Kaplan-Meier analysis. The patients were classified according to the Musculoskeletal Infection Society (MSIS) system, and risk factors for failure were identified. Mean follow-up was four years (2 to 11).

Results

Gram-positive bacteria were responsible for 16/17 (94%) of the re-infections where microbes were identified. Following the repeat two-stage exchange arthroplasty, survival free from any revision was 74% (95% confidence interval (CI) 56% to 96%, 14 at risk) at two years and 45% (95% CI 25% to 75%, five at risk) at five years. Failure to control infection resulted in re-operation or revision in 42%A of patients (8/19). Survival free from revision was not dependent on host grade.

Conclusion

Re-infection after two-stage exchange hip arthroplasty for PJI presents a challenging scenario. Repeat two-stage exchange arthroplasty has a low survival free from revision at five years (45%) and a high rate of re-infection (42%). Cite this article: Bone Joint J 2018;100-B:1157-61.

Preventing Complications Associated With Operating on Taper Corrosion

BACKGROUND

Revision total hip arthroplasty for the treatment of taper corrosion has become increasingly common. The purpose of this portion of the symposium was to describe the most common complications of this procedure and to delineate specific measures that might be taken to prevent these complications.

METHODS

A literature review was performed focusing on the results and complications of revision total hip arthroplasty performed for taper corrosion.

RESULTS

The most common modes of failure after revision total hip arthroplasty in the setting of taper corrosion include the 4 I's: infection, instability, implant loosening, and ions (recurrent adverse local tissue reaction).

CONCLUSION

Strategies specifically directed toward each of these 4 failure modes have the potential to significantly reduce the risk of complications.

Periprosthetic Joint Infection With Fungal Pathogens

BACKGROUND

Although there is abundant information about bacterial periprosthetic joint infections (PJIs), there is a notable paucity of information about fungal PJIs. The goals of this study are to describe the patient demographics, diagnostic findings, and treatment results of fungal PJIs after total joint arthroplasty.

METHODS

We identified 31 fungal PJIs (13 total hip arthroplasties and 18 total knee arthroplasties) in 31 patients treated between 1996 and 2014. This represented 0.9% of the 3525 PJIs treated at our institution during this time period. Candida species accounted for 81% of infections. The mean patient age at diagnosis of fungal PJI was 68 years. Mean follow-up after initiation of treatment was 4 years.

RESULTS

In the total hip arthroplasty cohort, survivorship free from all-cause revision or implant removal was 44% at 2 years. Survivorship free from reinfection was 38% at 2 years. Mean Harris hip score was 27 at final follow-up.In the total knee arthroplasty cohort, survivorship free from all-cause revision was 70% at 2 years. Survivorship free from reinfection was 76% at 2 years. Mean Knee Society scores were 36 at final follow-up.

CONCLUSION

Fungal PJIs are rare (0.9% of diagnosed PJIs). Survivorship free of all-cause revision or implant removal was very low in the hip group (44% at 2 years), but slightly better in the knee group (70% at 2 years). Moreover, clinical outcomes were poor with high perioperative complication rates. Improved treatment regimens are needed for this unsolved clinical problem.

Patients at Risk: Preoperative Opioid Use Affects Opioid Prescribing, Refills, and Outcomes After Total Knee Arthroplasty

BACKGROUND

The purpose of this study was to evaluate the effect of preoperative opioid use on opioid prescriptions, refills, and clinical outcomes after total knee arthroplasty (TKA).

METHODS

A retrospective review identified 53 patients on preoperative opioids who were matched 1:2 to 106 opioid-naive patients undergoing primary TKA with at least 2-year follow-up. Opioid refills, Knee Society Score (preoperative and follow-up), morphine equivalent dose (MED) prescribed, and persistent opioid use were compared between groups.

RESULTS

The average total MED prescribed at discharge was 1248 mg, ranging from 0 to 5600 mg. The average daily MED used before discharge was greater in the preoperative opioid group compared to the opioid-naive group (90 ± 75 mg vs 54 ± 42 mg; P = .001). The preoperative opioid group and opioid-naive group differed in terms of refills (1.3 ± 1.6 vs 0.4 ± 0.6; P = .0001), persistent opioid use (21 [39%] vs 5 [4%], P = .0001), postoperative KSS (85 ± 11 vs 90 ± 13; P = .01), and manipulations under anesthesia (4 [8%] vs 1 [1%], P = .03). Preoperative tramadol users had the same risk of refills, persistent opioid use, reduced KSS, and manipulation under anesthesia as those taking other opioids.

CONCLUSION

Preoperative opioid users were discharged with less opioids, required more refills, were more likely to remain on opioids, and required more manipulations under anesthesia than opioid-naive patients. These risks extended to preoperative tramadol users.

Continuous Posterior Lumbar Plexus Nerve Block Versus Periarticular Injection with Ropivacaine or Liposomal Bupivacaine for Total Hip Arthroplasty: A Three-Arm Randomized Clinical Trial

BACKGROUND

Debate surrounds the issue of whether peripheral nerve blockade or periarticular infiltration (PAI) should be employed within a contemporary, comprehensive multimodal analgesia pathway for total hip arthroplasty. We hypothesized that patients treated with a continuous posterior lumbar plexus block (PNB) would report less pain and consume less opioid medication than those treated with PAI.

METHODS

This investigator-initiated, independently funded, 3-arm randomized clinical trial (RCT) performed at a single high-volume institution compared postoperative analgesia interventions for elective, unilateral primary total hip arthroplasty: (1) PNB; (2) PAI with ropivacaine, ketorolac, and epinephrine (PAI-R); and (3) PAI with liposomal bupivacaine, ketorolac, and epinephrine (PAI-L) using computerized randomization. The primary outcome was maximum pain during the morning (06:00 to 12:00) of the first postoperative day (POD) on an ascending numeric rating scale (NRS) from 0 to 10. Pairwise treatment comparisons were performed using the rank-sum test, with a p value of <0.017 indicating significance (Bonferroni adjusted). A sample size of 150 provided 80% power to detect a difference of 2.0 NRS units.

RESULTS

We included 159 patients (51, 54, and 54 patients in the PNB, PAI-R, and PAI-L groups, respectively). No significant differences were found with respect to the primary end point on the morning of the first POD (median, 3.0, 4.0, and 3.0, respectively; p > 0.033 for all). Opioid consumption was low and did not differ across groups at any intervals. Median maximum pain on POD 1 was 5.0, 5.5, and 4.0, respectively, and was lower for the PAI-L group than for the PAI-R group (p = 0.006). On POD 2, maximum pain (median, 3.5, 5.0, and 3.5, respectively) was lower for the PNB group (p = 0.014) and PAI-L group (p = 0.016) compared with the PAI-R group. The PAI-L group was not significantly different from the PNB group with respect to any outcomes: postoperative opioid use including rescue intravenous opioid medication, length of stay, and hospital adverse events, and 3-month follow-up data including any complication.

CONCLUSIONS

In this RCT, we found a modest improvement with respect to analgesia in patients receiving PNB compared with those receiving PAI-R, but not compared with those who had PAI-L. Secondary analyses suggested that PNB or PAI-L provides superior postoperative analgesia compared with PAI-R. For primary total hip arthroplasty, a multimodal analgesic regimen including PNB or PAI-L provides opioid-limiting analgesia.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Outcomes of Primary Total Knee Arthroplasty in Patients With Hematopoietic Stem Cell Transplantation

Patients who have undergone hematopoietic stem cell transplantation to treat underlying bone marrow pathology represent a unique and potentially high-risk patient population for total knee arthroplasty (TKA). This study retrospectively reviewed 15 TKA procedures performed on 11 patients with a history of hematopoietic stem cell transplantation. The authors analyzed patient survivorship; clinical outcomes, including complications; and implant survivorship. Mean follow-up was 5 years (range, 2-10 years). Patient survivorship free from mortality was 91% (95% confidence interval, 76%-100%) and 55% (95% confidence interval, 25%-85%) at 2 and 5 years, respectively. Patients who underwent hematopoietic stem cell transplantation for multiple myeloma had a significantly higher 5-year mortality rate (100%) compared with patients who had an underlying diagnosis of non-Hodgkin's lymphoma (0%) (P=.008). Mean Knee Society Score improved to 83 postoperatively (P<.001). Two patients (13%) had postoperative wound healing complications that did not lead to periprosthetic joint infection; however, an additional patient (7%) underwent revision surgery at 5 years for periprosthetic joint infection. Estimated implant survivorship without revision was 80% (95% confidence interval, 60%-100%) at 5 years. Elective primary TKA does not appear to affect survivorship in patients with a history of hematopoietic stem cell transplantation. These patients have modest clinical outcomes, higher complication rates as a result of delayed wound healing, and poorer implant survivorship compared with historical control subjects. [Orthopedics. 2017; 40(5):e774-e778.].

Reproducibility and Precision of CT Scans to Evaluate Tibial Component Rotation

BACKGROUND

Component rotation likely plays a greater role on the survivorship and outcomes of total knee arthroplasties than is currently known. Our goal was to evaluate the precision, interobserver reliability, and intrarater reliability of tibial component rotation as measured by computed tomography (CT) scan, regardless of measurement technique.

METHODS

Three fellowship-trained, academic arthroplasty surgeons independently measured tibial component rotation on CT scans of 62 total knee arthroplasties using their methods of choice. Measurements were repeated at least 2 weeks after the initial measurement. The precision of the measurements was assessed using a formal 8-step protocol as the gold standard. Intraclass correlation coefficients (ICCs) were calculated to evaluate precision, interobserver agreement, and intrarater reliability RESULTS: The interobserver agreement between the 3 surgeons for tibial component rotation was also moderate (ICC = 0.52). The intrarater reliability of tibial rotation was excellent (ICC = 0.81). Comparison of surgeons' measurement to a validated gold standard revealed only moderate precision for tibial component rotation (ICC = 0.64).

CONCLUSION

Practicing surgeons measuring tibial rotation were internally consistent, but failed to demonstrate satisfactory precision and interobserver agreement. We support the adoption of standardized criteria for the measurement of tibial component rotation on CT scans.

Patient Perceptions of the Direct Anterior Hip Arthroplasty

BACKGROUND

The quest for less invasive surgical approaches for total hip arthroplasty (THA) has garnered much attention recently in the community, as well as media outlets. There are very little data demonstrating the actual differences in these approaches. We are unaware of any information documenting patients' perceptions of the direct anterior approach (DAA) for THA. The purpose of this study was to collect information regarding patients' perceptions of the DAA THA.

METHODS

We surveyed 166 consecutive new patients being evaluated for hip osteoarthritis in our outpatient clinic. Demographic data and their knowledge of the DAA were collected, as well as a number of questions on a 5-item Likert scale.

RESULTS

Forty-six (28%) responded that they were aware of the DAA. Respondents primarily learned about the DAA from friends and family (58%), and healthcare professionals (38%). Respondents agreed or strongly agreed that the DAA is less painful (70%), reduces the amount of time spent on a cane after surgery (70%), damages tissues less (68%), allows patients to more quickly return to work (64%), and allows for shorter hospital stays (62%), compared to other procedures. In addition, 30% felt there is a consensus among surgeons that the DAA is the safest and most effective procedure for THA.

CONCLUSION

Many people are unaware of the DAA, with a majority of healthcare information being transmitted by friends and family members. The patients' perceptions are inconsistent with published data about the DAA and are likely influenced by marketing and individuals surrounding them.

What Risks are Associated with Primary THA in Recipients of Hematopoietic Stem Cell Transplantation?

INTRODUCTION

As patients who receive hematopoietic stem cell transplantation are at increased risk of avascular necrosis (AVN) and subsequent degenerative arthritis, THA may be considered in some of these patients, particularly as overall patient survival improves for patients undergoing stem-cell transplants. Patients receiving hematopoietic stem cell transplantation theoretically are at increased risk of experiencing complications, infection, and poorer implant survivorship owing to the high prevalence of comorbid conditions, immunosuppressive therapy regimens including corticosteroids, and often low circulating hematopoietic cell lines; however, there is a paucity of studies elucidating these risks.

QUESTIONS/PURPOSES

We asked: (1) What is the overall mortality of patients with hematopoietic stem cell transplantation who have undergone THA? (2) What is the complication rate for these patients? (3) What are the revision and reoperation rates and implant survivorship for these patients?

PATIENTS AND METHODS

Between 1999 and 2013, we performed 42 THAs in 36 patients who underwent stem-cell transplants. Other than those who died, all were available for followup at a minimum of 2 years; of the patients whose procedures were done more than 10 years ago and who are not known to have died, two (5%) had not been seen in the last 5 years and so are considered lost to followup. All patients underwent thorough evaluation by the transplant team before arthroplasty; general contraindications included active medical comorbidities or evidence of unstable end-organ damage, active rejection, and critically low circulating hematopoietic cell lines. Underlying primary diseases leading to hematopoietic stem cell transplantation included lymphoma (14/42; 33%), plasma cell disorders (10/42; 24%), leukemia (9/42; 21%), and amyloidosis (3/42; 7%). Complications, reoperations, revisions, and implant and patient survivorship, were recorded from chart review and data from the institutional total joint registry. Mean followup was 5 years (range, 2-15 years).

RESULTS

Patient survivorship free of mortality was 91% (95% CI, 81%-100%) and 82% (95% CI, 68%-96%) at 2 and 5 years, respectively. Complications occurred in four of 42 THAs (10%); these complications included an intraoperative fracture and a venous thromboembolism. Revisions occurred in two of 42 (5%) THAs; there were no reoperations. Implant survivorship free of component revision for any reason or implant removal accounting for death as a competing risk was 93% (95% CI, 83%-100%) at 5 years.

CONCLUSION

With appropriate medical evaluation and comanagement by transplant specialists, carefully selected patients with hematopoietic stem cell transplants may undergo elective primary THA, although complications do occur in this relatively fragile patient population. Although implant survivorship was modest at 93% at 5 years, there was not a high risk of revision for infection. Improved outcomes for these patients may be expected as their medical management advances and additional comparative studies may clarify other important patient factors.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Repeat Two-Stage Exchange Arthroplasty for Periprosthetic Knee Infection Is Dependent on Host Grade

BACKGROUND

Two-stage exchange arthroplasty after a previous, failed 2-stage exchange procedure is fraught with difficulties, and there are no clear guidelines for treatment or prognosis given the heterogeneous group of patients in whom this procedure has been performed. The Musculoskeletal Infection Society (MSIS) staging system was developed in an attempt to stratify patients according to infection type, host status, and local soft-tissue status. The purpose of this study was to report the results of 2-stage exchange arthroplasty following a previous, failed 2-stage exchange protocol for periprosthetic knee infection as well as to identify risk factors for failure.

METHODS

We retrospectively identified 45 patients who had undergone 2 or more 2-stage exchange arthroplasties for periprosthetic knee infection from 2000 to 2013. Patients were stratified according to the MSIS system, and risk factors for failure were analyzed. The minimum follow-up was 2 years (mean, 6 years; range, 24 to 132 months).

RESULTS

At the time of follow-up, twenty-two (49%) of the patients had undergone another revision due to infection and 28 (62%) had undergone another revision for any reason. The infection recurred in 6 (75%) of 8 substantially immunocompromised hosts (MSIS type C) and in 3 (30%) of 10 uncompromised hosts (type A) following the second 2-stage exchange arthroplasty (p = 0.06). The infection recurred in 4 (80%) of 5 patients with compromise of the extremity (MSIS type 3) and 3 (33%) of 9 patients with an uncompromised extremity (type 1) (p = 0.27). Both extremely compromised hosts with an extremely compromised extremity (type C3) had recurrence of the infection whereas 3 (30%) of the 10 uncompromised patients with no or less compromise of the extremity (type A1 or A2) did. Five patients in the failure group underwent a third 2-stage exchange arthroplasty following reinfection, and 3 of them were infection-free at the time of the latest follow-up.

CONCLUSIONS

Uncompromised hosts (MSIS type A) with an acceptable wound (MSIS type 1 or 2) had a 70% rate of success (7 of 10) after a repeat 2-stage exchange arthroplasty, whereas type-B2 hosts had a 50% success rate (10 of 20). The repeat 2-stage exchange procedure failed in both type-C3 hosts; thus, alternative salvage procedures should be considered for such patients.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Survivorship After Primary Total Hip Arthroplasty in Solid-Organ Transplant Patients

BACKGROUND

Although a growing number of primary total hip arthroplasties (THAs) are being performed on solid-organ transplant (SOT) recipients, long-term patient and implant survivorships have not been well studied in contemporary transplant and arthroplasty practices.

METHODS

A total of 136 THAs (105 patients) with prior SOT were retrospectively reviewed from 2000 to 2013 at mean clinical follow-up of 5 years. The mean age was 59 years, with 39% being females. The most common SOT was renal (56%), followed by liver (24%).

RESULTS

Patient mortality was 3.8% and 13.3% at 2 and 5 years, respectively. There were 9 revisions (6.6%), including 5 (4%) for deep periprosthetic infection. Implant survivorship free of any revision was 95% and 94% at 2 and 5 years, respectively. Transplant type or surgical indication did not significantly impact patient or implant survivorship.

CONCLUSION

Compared with the general population, SOT patients undergoing THA have slightly higher mortality rates at 5 years. Implant survivorship free of revision was slightly lower than the general population, primarily due to an increased risk of periprosthetic joint infection.

Factors Associated With 20-Year Cumulative Risk of Infection After Aseptic Index Revision Total Knee Arthroplasty

BACKGROUND

The purpose of this study was to calculate the cumulative risk of periprosthetic joint infection (PJI) after aseptic index knee revisions and to identify the surgical, perioperative, and medical comorbidity risk factors associated with deep infection.

METHODS

We retrospectively reviewed 1802 aseptic index revision total knee arthroplasties performed at our institution from 1970 to 2000. From this cohort, there were 60 reoperations performed for deep infection.

RESULTS

The cumulative risk of infection at 1, 5, 10, and 20 years after index revision was 1%, 2.4%, 3.3%, and 5.6%, respectively.

CONCLUSIONS

Male gender, use of constrained implants, increased operative times, increased Charlson Comorbidity Index, and a history of liver disease were all significantly associated with PJI. The development of cardiovascular disease, endocrine disorders, and renal disease were also associated with PJI.

Diagnosis of adverse local tissue reactions following metal-on-metal hip arthroplasty

Metal-on-metal (MOM) bearing surfaces in hip arthroplasty have distinct advantages that led to the increase in popularity in North America in the early 2000s. However, with their increased use, concerns such as local cytotoxicity and hypersensitivity reactions leading to soft tissue damage and cystic mass formation (known collectively as adverse local tissue reactions (ALTR)) became apparent. The clinical presentation of ALTR is highly variable. The diagnosis of ALTR in MOM articulations in hip arthroplasty can be challenging and a combination of clinical presentation, physical examination, implant track record, component positioning, serum metal ion levels, cross-sectional imaging, histopathologic analysis, and consideration of alternative diagnoses are essential.

Revision total hip arthroplasty in patients with extensive proximal femoral bone loss using a fluted tapered modular femoral component

Revision total hip arthroplasty (THA) is challenging when there is severe loss of bone in the proximal femur. The purpose of this study was to evaluate the clinical and radiographic outcomes of revision THA in patients with severe proximal femoral bone loss treated with a fluted, tapered, modular femoral component. Between January 1998 and December 2004, 92 revision THAs were performed in 92 patients using a single fluted, tapered, modular femoral stem design. Pre-operative diagnoses included aseptic loosening, infection and peri-prosthetic fracture. Bone loss was categorised pre-operatively as Paprosky types III-IV, or Vancouver B3 in patients with a peri-prosthetic fracture. The mean clinical follow-up was 6.4 years (2 to 12). A total of 47 patients had peri-operative complications, 27 of whom required further surgery. However, most of these further operations involved retention of a well-fixed femoral stem, and 88/92 femoral components (97%) remained in situ. Of the four components requiring revision, three were revised for infection and were well fixed at the time of revision; only one (1%) was revised for aseptic loosening. The most common complications were post-operative instability (17 hips, 19%) and intra-operative femoral fracture during insertion of the stem (11 hips, 12%). Diaphyseal stress shielding was noted in 20 hips (22%). There were no fractures of the femoral component. At the final follow-up 78% of patients had minimal or no pain. Revision THA in patients with extensive proximal femoral bone loss using the Link MP fluted, tapered, modular stem led to a high rate of osseointegration of the stem at mid-term follow-up. Cite this article: Bone Joint J 2015; 97-B:312-17.

Diabetes mellitus, hyperglycemia, hemoglobin A1C and the risk of prosthetic joint infections in total hip and knee arthroplasty

Diabetes mellitus is an established risk factor for infections but evidence is conflicting to what extent perioperative hyperglycemia, glycemic control and treatment around the time of surgery modify the risk of prosthetic joint infections (PJIs). In a cohort of 20,171 total hip and knee arthroplasty procedures, we observed a significantly higher risk of PJIs among patients with a diagnosis of diabetes mellitus (hazard ratio [HR] 1.55, 95% CI 1.11, 2.16), patients using diabetes medications (HR 1.56, 95% CI 1.08, 2.25) and patients with perioperative hyperglycemia (HR 1.59, 95% CI 1.07, 2.35), but the effects were attenuated after adjusting for body mass index, type of surgery, ASA score and operative time. Although data were limited, there was no association between hemoglobin A1c values and PJIs.

Morbid obesity: a significant risk factor for failure of two-stage revision total hip arthroplasty for infection

BACKGROUND

Morbid obesity (BMI [body mass index], ≥40 kg/m2) is associated with a higher risk of complications, including infection and implant failure, following primary total hip arthroplasty. The purpose of this study was to compare the results of two-stage revision total hip arthroplasty for infection in a morbidly obese patient cohort (BMI, ≥40 kg/m2) and nonobese patients (BMI, <30 kg/m2).

METHODS

Using an institutional total joint registry, we reviewed the medical records of 653 patients treated with two-stage revision total hip arthroplasty for periprosthetic joint infection over a twenty-year period (1987 to 2007). Patients were stratified according to preoperative BMI. Thirty-three patients (fourteen male and nineteen female) with a BMI of ≥40 kg/m2 were identified. These patients were matched 1:2 with a cohort of sixty-six patients (twenty-eight male and thirty-eight female) of the same sex and similar age (91% within two years) who were not obese (BMI, <30 kg/m2). All patients had a minimum of five years of clinical follow-up (mean, 8.1 years in the morbidly obese group and 10.3 years in the nonobese group).

RESULTS

Compared with nonobese patients, morbidly obese patients had significantly greater rates of reinfection (18% compared with 2%, p<0.005), revision (42% compared with 11%, p<0.001) and reoperation for any reason (61% compared with 12%, p<0.001). Prior to surgery, the mean Harris Hip Score had been 50.6 in the morbidly obese group and 48.8 in the nonobese group, and these scores improved significantly in both groups postoperatively (p<0.01).

CONCLUSIONS

Morbidly obese patients have markedly elevated risks of reinfection, reoperation, and component resection as well as poorer intermediate-term clinical outcome scores compared with nonobese patients following revision total hip arthroplasty for periprosthetic joint infection.

How do I get out of this jam? Overcoming common intraoperative problems in primary total hip arthroplasty

Prompt attention is typically required in managing intraoperative problems associated with total hip arthroplasty. There is often limited time for consultation or a review of the literature. The treating surgeon should be familiar with treatment options, favored treatment methods, and should be able to implement the most appropriate and optimal treatment for his or her patient. Common intraoperative complications associated with primary total hip arthroplasty include difficulty gaining sufficient exposure, problems with cup fixation, challenges with implant anteversion, intraoperative fracture of the femur, and difficulties with intraoperative limb length and hip instability.

Uncemented Porous Tantalum Acetabular Components: Early Follow-Up and Failures in 599 Revision Total Hip Arthroplasties

BACKGROUND

The purpose of this study was to determine the early outcomes of 599 cases of revision THA performed using a porous tantalum cup.

METHODS

Clinical and radiographic data was sought in all patients at a minimum two years follow-up, after acetabular revision performed with a porous tantalum cup.

RESULTS

Of the 599 cases identified, there were 51 re-operations in 47 patients (7.8 percent). Cup removal was required in 14 of these cases (2.3 percent). The most common cause for cup removal was a septic joint (12). No cups were revised for aseptic loosening during the study period. There was one case of early cup migration. There were 17 incomplete lucencies not initially seen on post-operative films, but identified later, all were non-progressive on subsequent x-rays.

CONCLUSIONS

Early results of porous tantalum acetabular components in the revision setting demonstrate good initial stability and low re-operation rates at two years follow-up.

LEVEL OF EVIDENCE

Level 4: Case series.

Distal Femoral Subchondral Metastasis Mistaken for an Insufficiency Fracture and Treated with Total Knee Arthroplasty: A Case Report

CASE

A seventy-three-year-old woman who had been given the tentative diagnosis of spontaneous osteonecrosis presented to our clinic for a second opinion. Additional imaging and evaluation revealed the lesion to be a subchondral metastasis consistent with breast cancer. She received proper oncologic treatment and subsequent total knee arthroplasty.

CONCLUSION

Orthopaedic surgeons should be aware of the possibility of metastatic disease manifesting itself in the form of an isolated subchondral lesion about the knee. For patients with such lesions, treatment in the form of total knee arthroplasty is a viable option that can provide excellent pain relief and function.

External validation of the national healthcare safety network risk models for surgical site infections in total hip and knee replacements

BACKGROUND

The National Healthcare Safety Network surgical site infections risk models for hip (HPRO) and knee (KPRO) replacement are intended for case-mix adjustment when reporting surgical site infection rates across institutions, but they are not validated in external data sets.

OBJECTIVE

To evaluate the validity of HPRO and KPRO risk models and improvement in risk prediction with inclusion of information on morbid obesity and diabetes mellitus.

DESIGN

Retrospective cohort study.

PATIENTS

A single-center cohort of 21,941 hip and knee replacement procedures performed between 2002 and 2009.

METHODS

Discriminative ability was assessed using the concordance statistic (C statistic). Calibration was assessed using the Hosmer-Lemeshow goodness-of-fit tests.

RESULTS

The discrimination of HPRO was good, with a C statistic of 0.695 for surgical site infections and 0.749 for prosthetic joint infections. The discrimination of KPRO was worse than that of HPRO, with a C statistic of 0.592 for surgical site infections and 0.675 for prosthetic joint infections. Adding morbid obesity and diabetes mellitus to the HPRO and KPRO risk models modestly improved discrimination. There was no significant evidence of miscalibration based on the Hosmer-Lemeshow tests, but calibration of HPRO models appeared to be better than that of the KPRO models.

CONCLUSION

HPRO performed better than the KPRO in predicting surgical site infections after hip and knee replacements. Both fared well in predicting prosthetic joint infections.

Morbid obesity: a significant risk factor for failure of two-stage revision total knee arthroplasty for infection

BACKGROUND

Obese patients have a higher risk of complications following primary total knee arthroplasty, including periprosthetic joint infection. However, there is a paucity of data concerning the efficacy of two-stage revision arthroplasty in obese patients.

METHODS

We performed a two-to-one matched cohort study to compare the outcomes of thirty-seven morbidly obese patients (those with a body mass index of ≥ 40 kg/m(2)) who underwent two-stage revision total knee arthroplasty for periprosthetic joint infection following primary total knee arthroplasty with the outcomes of seventy-four non-obese patients (those with a body mass index of <30 kg/m(2)). Groups were matched by sex, age, and date of reimplantation. Outcomes included subsequent revision, reinfection, reoperation, and Knee Society pain and function scores. The minimum follow-up time was five years.

RESULTS

Morbidly obese patients had a significantly increased risk for revision surgery (32% compared with 11%; p < 0.01), reinfection (22% compared with 4%; p < 0.01), and reoperation (51% compared with 16%; p < 0.01). Implant survival rates were 80% for the morbidly obese group and 97% for the non-obese group at five years and 55% for the morbidly obese group and 82% for the non-obese group at ten years. Knee Society pain scores improved significantly following surgery in both groups; the mean scores (and standard deviation) were 50 ± 5 points for the morbidly obese group and 55 ± 2 points for the non-obese group (p = 0.06) preoperatively, 74 ± 5 points for the morbidly obese group and 89 ± 2 points for the non-obese group (p < 0.0001) at two years, 72 ± 6 points for the morbidly obese group and 88 ± 3 points for the non-obese group (p < 0.0001) at five years, and 56 ± 9 points for the morbidly obese group and 84 ± 3 points for the non-obese group (p = 0.01) at ten years.

CONCLUSIONS

Morbid obesity significantly increased the risk of subsequent revision, reoperation, and reinfection following two-stage revision total knee arthroplasty for infection. In addition, these patients had worse pain relief and overall function at intermediate-term clinical follow-up. Although two-stage revision should remain a standard treatment for chronic periprosthetic joint infection in morbidly obese patients, increased failure rates and poorer outcomes should be anticipated.

Uncemented porous tantalum acetabular components: early follow-up and failures in 613 primary total hip arthroplasties

Uncemented tantalum acetabular components were introduced in 1997. The purpose was to determine the 2- to 10-year results with this implant material in primary total hip arthroplasty. Our registry identified all primary total hip cases with porous tantalum cups implanted from 1997 to 2004. Clinical outcomes and radiographs were studied. 613 cases were identified. Seventeen percent of patients were lost to follow-up. Twenty-five reoperations were performed (4.4%). Acetabular cup removal occurred in 6 cases (1.2%). No cups were revised for aseptic loosening. Incomplete radiolucent lines were found on 9.3% of initial postoperative radiographs. At 2 years, 67% had resolved. Zero new radiolucent lines were detected. Two- to 10-year results of porous tantalum acetabular components for primary total hip arthroplasty demonstrate high rates of initial stability and apparent ingrowth.

Safety of clopidogrel in hip fracture surgery

OBJECTIVE

To compare postoperative outcomes of hip fracture surgery in patients who were and were not taking clopidogrel at the time of surgery.

PATIENTS AND METHODS

Using the Rochester Epidemiology Project database, we performed a population-based, retrospective cohort study comparing patients who were and were not taking clopidogrel at the time of hip fracture surgery between January 1, 1996, and June 30, 2010. Primary outcomes were perioperative bleeding and mortality. Secondary outcomes were perioperative thrombotic events.

RESULTS

During the study period, 40 residents of Olmsted County, Minnesota (median age, 83 years), who were taking clopidogrel underwent hip fracture repair. These 40 patients were matched 2:1 with 80 control patients (median age, 84 years). The groups were similar in age, sex, American Society of Anesthesiologists score, type of surgical procedure, and use of deep venous thrombosis prophylaxis. The mean time from admission to surgery was less than 36 hours for each cohort. Perioperative bleeding complications and mortality were not significantly different between patients who were and were not taking clopidogrel at the time of hip fracture surgery. Combined bleeding outcome criteria was met in 48% of the clopidogrel cohort and 45% of the control cohort (relative risk, 1.06; 95% CI, 0.70-1.58; P=.80). One-year mortality was 28% in the clopidogrel cohort and 29% in the control cohort (hazard ratio, 1.33; 95% CI, 0.84-2.12; P=.23).

CONCLUSION

Although the small sample size precludes making a definitive conclusion, we found no evidence that prompt surgical treatment of hip fracture in patients taking clopidogrel compromises perioperative outcomes.

Patients' perceptions of hip resurfacing arthroplasty

The purpose of this study was to understand patients' perceptions regarding hip resurfacing arthroplasty relative to conventional total hip arthroplasty (THA). A consecutive group of 139 patients being evaluated for hip symptoms were asked to complete a survey regarding hip resurfacing arthroplasty. Forty-one percent were aware of hip resurfacing arthroplasty, and 82% felt hip resurfacing arthroplasty was a safer procedure than THA. Seventy-nine percent felt there was less soft tissue damage associated with hip resurfacing arthroplasty, and 80% felt they would return to their activities more quickly. Eighty percent felt that their overall range of motion would be better following hip resurfacing arthroplasty. Patients' perceptions of hip resurfacing arthroplasty are inconsistent with the known published advantages and disadvantages of the procedure when compared to conventional THA. Most of the patients received their information from sources other than an orthopedic surgeon.

Comparison of intramedullary nailing and external fixation knee arthrodesis for the infected knee replacement

We analyzed knee arthrodesis for the infected total knee replacement (TKR) using two different fixation techniques. Patients undergoing knee arthrodesis for infected TKR were identified and rates of successful fusion and recurrence of infection were compared using Cox proportional hazard models. Eighty-five consecutive patients who underwent knee arthrodesis were followed until union, nonunion, amputation, or death. External fixation achieved successful fusion in 41 of 61 patients and was associated with a 4.9% rate of deep infection. Fusion was successful in 23 of 24 patients with intramedullary (IM) nailing and was associated with an 8.3% rate of deep infection. We observed similar fusion and infection rates with the two techniques. Thirty-four patients (40%) had complications. Knee arthrodesis remains a reasonable salvage alternative for the difficult infected TKR. Complication rates are high irrespective of the technique, and one must consider the risks of both nonunion and infection when choosing the fixation method in this setting. IM nailing appears to have a higher rate of successful union but a higher risk of recurrent infection when compared with external fixation knee arthrodesis.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Revision total knee arthroplasty with modular cemented stems: long-term follow-up

From 1989 to 1994, 72 patients (73 knees) were treated for an aseptic, failed primary total knee arthroplasty (TKA) at 1 institution with revision TKA using a posterior stabilized implant of 1 design with modular, fully cemented femoral and tibial stems. There were 70 knees in 69 patients followed for a minimum of 2 years, or until component rerevision or resection. The remaining 3 patients died or were followed up for less than 2 years. The median follow-up of living patients with retained components was 10.2 years. Four knees had both femoral and tibial components rerevised for aseptic loosening. One knee was rerevised for patellar loosening and polyethylene wear. Five- and 10-year implant survivorship free of revision for aseptic failure was 98% and 92%, respectively.

The role of stems and augments for bone loss in revision knee arthroplasty

The treatment of bone deficiencies during revision knee arthroplasty remains a challenging problem. The primary treatment options for these bone deficiencies include the use of structural allografts, impaction bone grafting, and the use of prosthetic augments. There have been no comparative series demonstrating the superiority of any of these techniques. Supplemental stem fixation should be used when using one of these treatment approaches. Although the use of cementless stems is currently more popular, the available literature suggests that cemented stem fixation provides a more reliable and durable construct for revision knee arthroplasty associated with severe bone deficiency.