Faculty Bibliography

BACKGROUND:Concerns have been voiced regarding how surgical approach impacts risk of dislocation after total hip arthroplasty (THA). This study investigated how surgical approach impacts rate, direction, and timing of dislocations following THA. METHODS:We conducted a retrospective review of 13,335 primary THAs from 2011 to 2020 and identified 118 patients with prosthetic hip dislocation. Patients were stratified into cohorts by surgical approach used during primary THA. Patient demographics, index THA acetabular cup positioning, number, direction, timing of dislocations, and subsequent revisions were collected. RESULTS:Dislocation rate differed significantly between posterior approach (PA), direct anterior approach (DAA), and laterally-based approach (LA) (1.1 versus 0.7% versus 0.5%, P = .026). Rate of hips dislocating anteriorly was lowest in the PA group (19.2%) compared to LA (50.0%) and DAA groups (38.2%, P = .044). There was no difference in rate of hips dislocating posteriorly (P = .159) or multidirectional (P = .508) instability; notably 58.8% of dislocations in the DAA cohort occurred posteriorly. There were no differences in dislocation timing or revision rate. Acetabular anteversion was highest in the PA cohort compared to DAA and LA (21.5 versus 19.2 versus 11.7 degrees, P = .049). CONCLUSION:After THA, patients in the PA group had a slightly higher dislocation rate compared to the DAA and LA groups. The PA group had a lower rate of anterior dislocation and nearly 60% of DAA dislocations occurred posteriorly. However, with no differences in other parameters including revision rates or timing, our data suggests surgical approach may impact dislocation characteristics to a lesser degree than previous studies have suggested.

OBJECTIVE:To develop evidence-based consensus recommendations for the optimal timing of hip and knee arthroplasty to improve patient-important outcomes including, but not limited to, pain, function, infection, hospitalization, and death at 1 year for patients with symptomatic and radiographic moderate-to-severe osteoarthritis or advanced symptomatic osteonecrosis with secondary arthritis of the hip or knee who have previously attempted nonoperative therapy, and for whom nonoperative therapy was ineffective, and who have chosen to undergo elective hip or knee arthroplasty (collectively referred to as TJA). METHODS:We developed 13 clinically relevant population, intervention, comparator, outcomes (PICO) questions. After a systematic literature review, the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to rate the quality of evidence (high, moderate, low, or very low), and evidence tables were created. A Voting Panel, including 13 physicians and patients, discussed the PICO questions until consensus was achieved on the direction (for/against) and strength (strong/conditional) of the recommendations. RESULTS:The panel conditionally recommended against delaying TJA to pursue additional nonoperative treatment including physical therapy, nonsteroidal antiinflammatory drugs, ambulatory aids, and intraarticular injections. It conditionally recommended delaying TJA for nicotine reduction or cessation. The panel conditionally recommended delay for better glycemic control for patients who have diabetes mellitus, although no specific measure or level was identified. There was consensus that obesity by itself was not a reason for delay, but that weight loss should be strongly encouraged, and the increase in operative risk should be discussed. The panel conditionally recommended against delay in patients who have severe deformity or bone loss, or in patients who have a neuropathic joint. Evidence for all recommendations was graded as low or very low quality. CONCLUSION/CONCLUSIONS:This guideline provides evidence-based recommendations regarding the optimal timing of TJA in patients who have symptomatic and radiographic moderate-to-severe osteoarthritis or advanced symptomatic osteonecrosis with secondary arthritis for whom nonoperative therapy was ineffective to improve patient-important outcomes, including pain, function, infection, hospitalization, and death at 1 year. We acknowledge that the evidence is of low quality primarily due to indirectness and hope future research will allow for further refinement of the recommendations.

BACKGROUND:Revision total knee arthroplasty (rTKA) can be performed with isolated tibial, isolated femoral, and combined tibial and femoral component exchange for different indications. Replacement of only 1 fixed component in rTKA leads to shorter operative times and decreased complexity. We sought to compare functional outcomes and rates of rerevision in patients undergoing partial and full rTKA. METHODS:This retrospective study examined all aseptic rTKA patients with a minimum follow-up of 2 years in a single center between September 2011 and December 2019. Patients were divided into two groups: full rTKA (F-rTKA) if both components (femoral and tibial) were revised and partial rTKA (P-rTKA) if only 1 component was revised. A total of 293 patients (P-rTKA = 76, F-rTKA = 217) were included. RESULTS:P-rTKA patients had significantly shorter surgical time (109 ± 37 Versus. 141 ± 44 minutes, P < .001). At mean follow-up of 4.2 (range 2.2-6.2) years, rerevision rates did not significantly differ between groups (11.8 Versus. 16.1%, P = .358). Improvements in postoperative Visual Analogue Scale (VAS) pain and Knee Injury and Osteoarthritis Scale (KOOS), Joint Replacement scores were similar as well (P = .100 and P = .140, respectively). For patients undergoing rTKA due to aseptic loosening, freedom from rerevision due to aseptic loosening was similar between groups (100 Versus. 97.8%, P = .321). For patients undergoing rTKA due to instability, freedom from rerevision due to instability did not significantly differ as well (100 Versus. 98.1%, P = .683). In the P-rTKA cohort, freedom from all-cause and aseptic revision of preserved components was 96.1% and 98.7% at the 2-year follow-up. CONCLUSION:Compared to F-rTKA, P-rTKA yielded similar functional outcomes and implant survivorship with shorter surgical time. When indications and component compatibility allow for such a procedure, surgeons can expect good outcomes when performing P-rTKA.

BACKGROUND:Periprosthetic joint infection (PJI) and subsequent revision surgeries may affect patients' social and physical health, ability to complete daily activities, and disability status. This study sought to determine how PJI affects patients' quality of life through patient-reported outcome measures with minimum 1-year follow-up. METHODS:Patients who suffered PJI following primary total joint arthroplasty (TJA) from 2012 to 2021 were retrospectively reviewed. Patients met Musculoskeletal Infection Society criteria for acute or chronic PJI, underwent revision TJA surgery, and had at least 1 year of follow-up. Patients were surveyed regarding how PJI affected their work and disability status, as well as their mental and physical health. Outcome measures were compared between acute and chronic PJIs. In total, 318 patients (48.4% total knee arthroplasty and 51.6% total hip arthroplasty) met inclusion criteria. RESULTS:Following surgical treatment for knee and hip PJI, a substantial proportion of patients reported that they were unable to negotiate stairs (20.5%), had worse physical health (39.6%), and suffered worse mental health (25.2%). A high proportion of patients reported worse quality of life (38.5%) and social satisfaction (35.3%) following PJI. Worse reported patient-reported outcome measures including patients' ability to complete daily physical activities were found among patients undergoing treatment for chronic PJI, and also, 23% of patients regretted their initial decision to pursue primary TJA. CONCLUSIONS:A PJI negatively affects patients' ability to carry out everyday activities. This patient population is prone to report challenges overcoming disability and returning to work. Patients should be adequately educated regarding the risk of PJI to decrease later potential regrets. LEVEL OF EVIDENCE/METHODS:Case series (IV).

INTRODUCTION/BACKGROUND:Prior studies have demonstrated an association between time to revision total knee arthroplasty (rTKA) and indication; however, the impact of early versus late revision on post-operative outcomes has not been reported. MATERIALS AND METHODS/METHODS:A retrospective, observational study examined patients who underwent unilateral, aseptic rTKA at an academic orthopedic hospital between 6/2011 and 4/2020 with > 1-year of follow-up. Patients were early revisions if they were revised within 2 years of primary TKA (pTKA) or late revisions if revised after greater than 2 years. Patient demographics, surgical factors, and post-operative outcomes were compared. RESULTS:470 rTKA were included (199 early, 271 late). Early rTKA patients were younger by 2.5 years (p = 0.002). The predominant indications for early rTKA were instability (28.6%) and arthrofibrosis/stiffness (26.6%), and the predominant indications for late rTKA were aseptic loosening (45.8%) and instability (26.2%; p < 0.001). Late rTKA had longer operative times (119.20 ± 51.94 vs. 103.93 ± 44.66 min; p < 0.001). There were no differences in rTKA type, disposition, hospital length of stay, all-cause 90-day emergency department visits and readmissions, reoperations, and number of re-revisions. CONCLUSIONS:Aseptic rTKA performed before 2 years had different indications but demonstrated similar outcomes to those performed later. Early revisions had shorter surgical times, which could be attributed to differences in rTKA indication. LEVEL OF EVIDENCE/METHODS:III, retrospective observational analysis.

The management of acetabular bone loss during revision arthroplasty is a challenging problem. Not only are there a wide variety of potential defects, but the location of these defects can also drastically change the hip center of rotation, stability, and biomechanics. First, the assessment of the severity and location of bone loss preoperatively is highlighted as it is imperative to evaluate the acetabular bone stock remaining. It is especially important to determine how to identify a pelvic discontinuity. Various classification systems are discussed to help surgeons adequately assess and evaluate these defects. There are also numerous implants and treatment strategies available to manage the problem, all of which are determined by that preoperative assessment and classification. We review the history of managing these defects and how management has evolved into modern designs, including but not limited to structural allograft, distraction arthroplasty, jumbo cups, metal augments, cup-cages, and custom triflanges. This review then describes the up-to-date clinical results of these various techniques, highlighting the surgical execution needed to obtain a successful result. By describing the preoperative assessment, the acetabular defect classifications, and proposed evidence-based treatment algorithms, we hope that this review will enhance the understanding of these challenging reconstructions in the setting of acetabular bone defects.

Total joint arthroplasty relies on the use of biomaterials that are biologically inert and capable of forming wear-resistant articulating surfaces. Polyethylene use in arthroplasty has become ubiquitous since its introduction in the 1960s. Early arthroplasty procedures of the hip utilized poly-tetra-flouroethylene, or "Teflon," due to its low coefficient of friction that was presumed to closely mimic the hyaline cartilage of native joints. Early catastrophic wear of Teflon caused a significant local tissue reaction contributing to osteolysis, aseptic loosening, and clinical failure ultimately limiting the material's surgical utility. Advancements in biomaterial synthesis and processing led to the fortuitous discovery of ultra-high-molecular-weight-polyethylene (UHMWPE) and the eventual evolution to highly cross-linked polyethylene (HXLPE) as a bearing surface in hip arthroplasties with robust, long-term clinical success. Ultra-high-molecularweight-polyethylene was readily adopted for use in total knee arthroplasty following the material's successful use in hip replacement, however, the unique biomechanics of the knee have posed unique challenges. The use of HXLPE in knee arthroplasty has increased, however, clear data regarding its benefit over UHMWPE are conflicting. Recently, clinical as well as research and development studies of UHMWPE and HXLPE have focused on alternative postprocessing methods to optimize material stability and wear resistance. Second generation HXLPE utilizing sequential annealing processes or vitamin E to stabilize free radicals are promising means to improve mechanical stability and wear resistance for use in joint arthroplasty, however, more data is required to evaluate long-term outcomes and cost-effectiveness. In this review, we discuss the history and innovation of polyethylene use in orthopedic surgery and evaluate the current literature on outcomes of polyethylene use in hip and knee replacement.

BACKGROUND:Concerns regarding the effects of dexamethasone on diabetics' glucose control have stymied its use following total joint arthroplasty. This study aimed to evaluate the effects of 2 intravenous (IV) perioperative doses of dexamethasone on glucose levels, pain scores, and inpatient opioid consumption following total joint arthroplasty in diabetic patients. METHODS:A retrospective review of 523 diabetic patients who underwent primary elective THA and 953 diabetic patients who underwent primary elective total knee arthroplasty (TKA) between May 6, 2020, and December 17, 2021 was conducted. Patients who received 1 dose (1D) of perioperative dexamethasone 10 mg IV were compared to patients who received 2 doses (2D). Primary outcomes included postoperative glucose levels, opioid consumption as morphine milligram equivalences, postoperative pain as Verbal Rating Scale pain scores, and postoperative complications. RESULTS:The 2D TKA cohort had significantly greater average and maximum blood glucose levels from 24 to 60 hours compared to the 1D TKA cohort. The 2D THA cohort had significantly greater average blood glucose levels at 24 to 36 hours compared to the 1D THA cohort. However, the 2D TKA group had significantly reduced opioid consumption from 24 to 72 hours and reduced total consumption compared to the 1D TKA group. Verbal Rating Scale pain scores did not differ between cohorts for both TKA and THA at any interval. CONCLUSION/CONCLUSIONS:Administration of a second perioperative dose of dexamethasone was associated with increased postoperative blood glucose levels. However, the observed effect on glucose control may not outweigh the clinical benefits of a second perioperative dose of glucocorticoids.

INTRODUCTION/BACKGROUND:Infection after total knee arthroplasty (TKA) impacts the patient, surgeon, and healthcare system significantly. Surgeons routinely use antibiotic-loaded bone cement (ALBC) in attempts to mitigate infection; however, little evidence supports the efficacy of ALBC in reducing infection rates compared to non-antibiotic-loaded bone cement (non-ALBC) in primary TKA. Our study compares infection rates of patients undergoing TKA with ALBC to those with non-ALBC to assess its efficacy in primary TKA. METHODS:A retrospective review of all primary, elective, cemented TKA patients over the age of 18 between 2011 and 2020 was conducted at an orthopedic specialty hospital. Patients were stratified into two cohorts based on cement type: ALBC (loaded with gentamicin or tobramycin) or non-ALBC. Baseline characteristics and infection rates determined by MSIS criteria were collected. Multilinear and multivariate logistic regressions were performed to limit significant differences in demographics. Independent samples t test and chi-squared test were used to compare means and proportions, respectively, between the two cohorts. RESULTS:) and Charlson Comorbidity Index values (4.51 ± 2.15 vs. 4.04 ± 1.92) were more likely to receive ALBC. The infection rate in the non-ALBC was 0.8% (63/7,980), while the rate in the ALBC was 0.5% (7/1,386). After adjusting for confounders, the difference in rates was not significant between the two groups (OR [95% CI]: 1.53 [0.69-3.38], p = 0.298). Furthermore, a sub-analysis comparing the infection rates within various demographic categories also showed no significant differences between the two groups. CONCLUSION/CONCLUSIONS:Compared to non-ALBC, the overall infection rate in primary TKA was slightly lower when using ALBC; however, the difference was not statistically significant. When stratifying by comorbidity, use of ALBC still showed no statistical significance in reducing the risk of periprosthetic joint infection. Therefore, the advantage of antibiotics in bone cement to prevent infection in primary TKA is not yet elucidated. Further prospective, multicenter studies regarding the clinical benefits of antibiotic use in bone cement for primary TKA are warranted.