Faculty Bibliography

While there have been great advancements in total knee arthroplasty (TKA) over the past 50 years, anterior knee pain (AKP) remains the most common concern among patients postoperatively. Despite exhausting evidence supporting no clinical difference in AKP with resurfaced vs. unresurfaced patellae in TKA, 87% of TKAs are resurfaced in the United States, compared with 2% in other countries. These large practice variations underscore a lack of consensus regarding the role of the patella and the approach to the anterior compartment of the knee in TKA. The aim of this review was to go beyond patellar resurfacing and describe the effects that surgical technique and implant design may have on AKP in current TKA.

BACKGROUND:Unicompartmental knee arthroplasty (UKA) may offer advantages over total knee arthroplasty (TKA) for select patients, but implant failure leading to conversion to TKA remains a concern. The purpose of this study was to compare two-year conversion rates to TKA following UKA performed by arthroplasty fellowship-trained surgeons versus surgeons who did not have arthroplasty fellowship training at a single academic institution. METHODS:A retrospective review was performed of primary UKAs conducted at a single academic institution between 2010 and 2023, which had at least two years of follow-up and implant data available. Cases were grouped based on surgeon fellowship training. Demographics, operative characteristics, postoperative complications, and conversion to TKA were analyzed at two and five years, with characterization of all TKAs performed within five years. Implant survivorship was assessed using Kaplan-Meier analysis; group comparisons used Chi-square or Fisher exact tests as appropriate. A total of 413 UKAs were included, with 202 performed by arthroplasty-trained surgeons and 211 by non-arthroplasty-trained surgeons. Patients in the arthroplasty-trained group were older (mean 62.9 versus 58.5 years, P<0.001) and had higher Charlson Comorbidity Index scores (mean 5.03 versus 4.6, P<0.001). Technology utilization differed, with greater robotic use among non-arthroplasty-trained surgeons (84.4 versus 59.4%, P<0.001). RESULTS:At two years, conversion to TKA occurred in 2.5% of cases performed by arthroplasty-trained surgeons compared with 5.7% in the non-arthroplasty-trained group (P=0.049). Overall complication rates did not differ. Lateral UKA demonstrated significantly worse survivorship than medial UKA (log-rank P=0.0004). Among 29 TKAs performed within five years, indications and operative characteristics were similar between groups, but revision surgeon specialty differed significantly (P=0.001). CONCLUSIONS:Arthroplasty fellowship training was associated with a lower observed two-year conversion rate to TKA despite treatment of older, more comorbid patients and lower utilization of robotics. Failure patterns and survivorship beyond two years were similar.

BACKGROUND:Total hip arthroplasty (THA) is commonly performed using either an anterior- or posterior-based approach (AA or PA), with similar long-term outcomes. However, operative timings, including time for patient positioning, device implantation, wound closure, and total operating room (OR) time, may differ between these approaches. This study assessed differences in various OR timings between AA and PA for primary THA. METHODS:A retrospective review was performed of all patients who underwent primary, unilateral, elective THA at our large urban academic medical center between January 1, 2019, and January 31, 2025. Patient demographics and operative parameters were determined from clinical and operative records. Surgeons who began practicing during the study period had their first 50 cases excluded. Perioperative timings were compared between approaches. Multivariable regression analyses controlled for age, American Society of Anesthesiologists status, body mass index, cementation, robotic use, navigation assistance use, discharge disposition, sex, smoking status, and year of surgery. There were 8,120 procedures included (4,670 PA and 3,450 AA). RESULTS:The AA had shorter total OR time (156.7 versus 167.4 minutes, P < 0.001). Regression analysis found AA was associated with longer implantation time (+3.3 minutes, P < 0.001), but shorter set-up time (-2.0 minutes, P < 0.001), closure time (-7.5 minutes, P < 0.001), overall operative time (-4.2 minutes, P < 0.001), and take-down time (-3.6 minutes, P < 0.001). Cement fixation had an increased effect on AA operative times compared to PA (+28.9 versus +14.4 minutes; P < 0.001). CONCLUSIONS:Anterior approach THA procedures displayed faster set-up, closure, take-down, and OR times compared to PA. Controlling for covariates, AA reduces total OR time by nearly 10 minutes, although operative time with AA is more significantly impacted by cementation. Further studies investigating the cost analysis of AA versus PA are needed to contextualize these findings regarding timing.

PURPOSE/UNASSIGNED:The impact of altering a patient's hip offset during total hip arthroplasty (THA) on periprosthetic fracture risk is unknown. The purpose of this study was to compare periprosthetic fracture risk in patients where THA offset was "matched" to their contralateral native hip versus those where offset was mismatched. MATERIALS AND METHODS/UNASSIGNED:-tests and chi square analyses were used for data comparison. Relative risk (RR) with a 95% confidence interval (CI) was then calculated. RESULTS/UNASSIGNED:=0.015). CONCLUSION/UNASSIGNED:Failure to restore a patient's offset during THA is associated with increased rates of periprosthetic fracture. Although restoration of native hip anatomy is an important technical consideration of this procedure, alterations in the hip lever arm may predispose patients to periprosthetic fracture.

BACKGROUND:Solid organ transplant (SOT) patients undergoing total joint arthroplasty (TJA) may be at higher risk for complications due to complex medical and surgical histories, chronic immunosuppressive medications, and significant ongoing comorbidities. This study aimed to evaluate postoperative outcomes following primary, elective TJA in patients with a history of SOT. METHODS:We retrospectively reviewed 53,043 primary, elective TJA patients from 2011 to 2025. Patients were screened for SOT history prior to TJA. All SOT patients were taking some form of immunosuppressive medication following their transplantation. Demographics, SOT details, and surgical data were obtained. SOT patients (n = 70) underwent a nearest-neighbor 1:3 propensity-score matching to non-SOT (NSOT) controls (n = 210) based on age, sex, smoking, Charlson Comorbidity Index, body-mass index, and TJA indication. Kidney transplants were most common (61.4%), followed by liver (24.3%), and heart (8.6%). Differences in surgical outcomes and postoperative complications between the patients were investigated using Chi-squared tests, independent t-tests and effect size (ES) estimates. Baseline characteristics did not differ between the groups (P > 0.05). RESULTS:SOT patients had significantly longer hospital stays (92 vs. 51 h, P < 0.001, ES = 0.82), higher rates of discharge to skilled nursing facilities (SNF) (15.7% vs. 5.7%, P = 0.014, ES = 0.17) and all-cause 90 day readmissions (15.7% vs. 6.7%, P = 0.040, ES = 0.12), primarily driven by non-surgical reasons (14.3% vs. 4.3%, P = 0.010, ES = 0.16) compared to NSOT patients. All-cause revision rates were comparable between SOT and NSOT patients (4.3% vs. 3.8%, P = 0.999), including aseptic (2.9% vs. 1.9%, P = 0.642) and septic causes (1.4% vs. 1.9%, P = 0.999). CONCLUSIONS:Despite higher rates of SNF discharge and non-surgical 90 day readmissions, SOT patients achieved similar all-cause, septic, and aseptic revision rates, compared to NSOT patients. These findings suggest that compared to well-matched comorbid controls, SOT patients can safely undergo elective TJA with comparable revision risk. Enhanced perioperative care may help reduce readmission risks in this complex population.

BACKGROUND/UNASSIGNED:Arthrofibrosis represents a source of patient dissatisfaction following total knee arthroplasty (TKA). The purpose of this systematic review and meta-analysis was to evaluate the efficacy of perioperative angiotensin II receptor blockers (ARBs) as anti-fibrotic agents in patients undergoing total knee arthroplasty (TKA). METHODS/UNASSIGNED:The Medline, Embase and Cochrane library databases were systematically reviewed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The outcome measures of interest were postoperative knee range of motion (ROM), rates of manipulation under anesthesia (MUA) and revision rates. RESULTS/UNASSIGNED: = 0.3349). CONCLUSION/UNASSIGNED:This systematic review and meta-analysis found that the utilization of perioperative ARBs were not associated with superior postoperative knee ROM nor lower rates of MUA in patients undergoing TKA. Additionally, no difference in revision TKA rates existed between patients in the ARB cohort compared to the control cohort. Based on the current available data, it is the author's current recommendation that perioperative ARB usage is not indicated in the setting of TKA for the prevention of arthrofibrosis. However, this analysis should be interpreted in light of the low level of evidence and under-reporting of data of the included studies. Thus, higher-level evidence, prospective, comparative studies should be conducted to definitively identify if perioperative ARBs can be utilized as effective anti-fibrotic agents in the setting of TKA.

INTRODUCTION/BACKGROUND:Use of the direct anterior approach (DAA) in total hip arthroplasty (THA) has increased, with suggested benefits of faster recovery and less pain. However, consensus regarding the optimal approach is lacking. This study compared post-operative pain, functional recovery, and opioid use between DAA and posterior approach (PA) THA. METHODS:-tests. RESULTS: 0.001), but these small differences do not reflect clinical significance. MME comparison showed a trend towards decreased opioid consumption within the DAA cohort, but the clinical relevance of these differences is unknown. CONCLUSIONS:Pain, function, and opioid use were largely comparable between DAA and PA, with minor statistical differences unlikely to be clinically meaningful.

BACKGROUND:Robotic and navigation-assisted total knee arthroplasty (TKA) systems aim to optimize surgical performance; however, their influence on the speed of functional recovery remains unclear. This study compared the time to achieve a minimal clinically important difference (MCID) among patients undergoing robotic-assisted (RA), navigation-assisted (NA), and conventional TKA using Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS-JR) questionnaires. METHODS:This retrospective cohort study included patients undergoing primary TKA for osteoarthritis at a tertiary academic center from July 2017 to July 2024. Inclusion required preoperative and postoperative KOOS-JR scores within 12 months of surgery. Exclusion criteria were non-osteoarthritis indications, bilateral procedures, or revision within one year. The MCID was defined using both anchor-based and distribution-based methods. The time to MCID was analyzed using multivariable interval-censored accelerated failure time models, accounting for clinical and demographic variables and the operating surgeon. A total of 2,002 patients met the inclusion criteria: 433 (21.6%) underwent RA-TKA, 713 (35.6%) NA-TKA, and 856 (42.8%) conventional TKA. RESULTS:Both technology-assisted approaches were associated with faster MCID achievement compared to conventional TKA. Using distribution-based thresholds, NA-TKA achieved MCID 29% faster (time ratio [TR] = 0.71, 95% confidence interval (CI): 0.58 to 0.88, P = 0.002) and RA-TKA 26% faster (TR = 0.74, 95% CI: 0.57 to 0.95, P = 0.018), with covariate-standardized estimated median times of 19.9, 20.7, and 28.0 days, respectively. Using anchor-based thresholds, NA-TKA achieved MCID 27% faster (TR = 0.73, 95% CI: 0.57 to 0.95, P = 0.017) and RA-TKA 26% faster (TR = 0.74, 95% CI: 0.55 to 1.00, P = 0.050), with corresponding median times of 52.8, 53.5, and 71.9 days. The one-year MCID attainment rates were similar across all techniques (P > 0.6 for both definitions). CONCLUSIONS:Both RA-TKA and NA-TKA were associated with 26 to 29% faster achievement of clinically meaningful improvement compared with conventional TKA, corresponding to approximately seven to 19 fewer days to reach MCID, despite similar one-year attainment rates. Prospective multicenter studies are needed to validate these results and determine whether accelerated recovery translates to advantages in quality of life, healthcare utilization, and patient satisfaction.

BACKGROUND:Postoperative improvement in patient-reported outcomes is a key measure of total hip arthroplasty success. The Minimum Clinically Important Difference (MCID) represents the smallest improvement perceived as beneficial. Distribution-based MCIDs have been criticized for producing thresholds smaller than anchor-based values, questioning their clinical relevance. We hypothesized they may capture early biological recovery signals associated with subsequent patient-reported outcomes and aimed to determine whether failure to achieve an early distribution-based MCID (seven to 31 days) was associated with failure to achieve a late anchor-based MCID (90 to 365 days). METHODS:This retrospective cohort study included patients undergoing primary unilateral total hip arthroplasty for osteoarthritis from January 1, 2021, to January 1, 2025, comprising 844 patients. Patients were included if they completed 'Hip disability and Osteoarthritis Outcome Score, Joint Replacement' questionnaires preoperatively, at seven to 31 days, and at 90 to 365 days. Distribution-based MCID was defined as a ≥ 7.8-point improvement, and anchor-based MCID as ≥ 23 points. Multivariable regression assessed associations between early distribution-based and late anchor-based MCID failure, adjusting for demographics and clinical factors. RESULTS:In the early period (seven to 31 days), 565 patients (67.0%) achieved the distribution-based MCID, whereas 573 (67.9%) achieved the late anchor-based MCID (90 to 365 days). Among patients who failed to attain an early distribution-based MCID, 54.1% (151 of 279) also failed the late anchor-based MCID, compared with 21.2% (120 of 565) among early achievers (P < 0.001). Early distribution-based MCID failure was a strong independent predictor of late anchor-based MCID failure (odds ratio: 2.61; 95% confidence interval: 1.85 to 3.68; P < 0.001). Higher baseline Hip disability and Osteoarthritis Outcome Score, Joint Replacement scores and facility-based discharge were also independently associated with late failure (P < 0.05). CONCLUSIONS:Failure to achieve an early distribution-based MCID is strongly associated with poor patient-reported outcomes up to one year. Early distribution-based MCID attainment may represent an important prognostic marker, enabling timely clinical intervention.

The use of technology in adult reconstruction (AR) reflects a balance of perceived utility, workflow considerations, and training exposure. This study evaluated whether exposure to technology during residency and fellowship training influences early-career AR surgeons’ utilization of and attitudes towards technology in total joint arthroplasty (TJA). An online survey was distributed to a nationwide cohort of 51 AR surgeons who completed fellowship between 2011 and 2022 at 13 U.S. programs. Survey items assessed exposure to technology during training, utilization, and perceived impact of technology on clinical practice. 36 surgeons (71%) reported using technology in fewer than half their training cases (< 50% group), while 15 (29%) reported use in the majority of cases (> 50% group). Most surgeons (88%) reported access to technology in their current practice, with no statistically significant difference between training exposure groups (p = 0.999). Similarly, among those with access, most surgeons (78%) reported using technology in their current practice, with no statistically significant difference between training groups (p = 0.238). However, surgeons with greater exposure rated the importance of technology in TJA and its impact on patient outcomes significantly higher (p = 0.003 for both). Greater exposure to technology during training was thus associated with higher perceived value, though no significant differences in access or utilization in early practice were observed.