Is a Failed Spinal Attempt Associated with a Worse Clinical Course Following Primary Total Hip and Knee Arthroplasty?

INTRODUCTION: Spinal anesthesia (SA) is the preferred anesthesia modality for total joint arthroplasty (TJA). However, studies establishing SA as preferential may be subject to selection bias given that general anesthesia (GA) is often selectively utilized on more difficult, higher-risk operations. The optimal comparison group, therefore, is the patient converted to GA due to a failed attempt at SA. The purpose of this study was to determine risk factors and outcomes following failed SA with conversion to GA during primary total hip (THA) or knee arthroplasty (TKA). METHODS: A consecutive cohort of 4,483 patients who underwent primary TJA at our institution was identified (2,004 THA and 2,479 TKA). Of these patients, 3,307 underwent GA (73.8%), 1,056 underwent SA (23.3%), and 130 patients failed SA with conversion to GA (2.90%). Primary outcomes included rescue analgesia requirement in the post-anesthesia care unit (PACU), time to ambulation, pain scores in the PACU, estimated blood loss (EBL), and 90-day complications. RESULTS: Risk factors for SA failure included older age and a higher comorbidity burden. Failure of SA was associated with increased EBL, rescue intravenous (IV) opioid use, and time to ambulation when compared to the successful SA group in both THA and TKA patients (P < 0.001). The anesthesia modality was not associated with significant differences in PACU pain scores. The 90-day complication rate was similar between the failed SA and GA groups. There was a higher incidence of post-operative pain prompting unplanned visits and thromboembolism when comparing failed SA to successful SA in both THA and TKA patients (P < 0.05). CONCLUSION: In our series, patients who had failed SA demonstrated inferior outcomes to patients receiving successful SA and similar outcomes to patients receiving GA who did not have an SA attempt. This emphasizes the importance of success in the initial attempt at SA for optimizing outcomes following TJA.

Can ChatGPT Answer Patient Questions Regarding Total Knee Arthroplasty?

The internet has introduced many resources frequently accessed by patients prior to orthopaedic visits. Recently, Chat Generative Pre-Trained Transformer, an artificial intelligence-based chat application, has become publicly and freely available. The interface uses deep learning technology to mimic human interaction and provide convincing answers to questions posed by users. With its rapidly expanding usership, it is reasonable to assume that patients will soon use this technology for preoperative education. Therefore, we sought to determine the accuracy of answers to frequently asked questions (FAQs) pertaining to total knee arthroplasty (TKA).Ten FAQs were posed to the chatbot during a single online interaction with no follow-up questions or repetition. All 10 FAQs were analyzed for accuracy using an evidence-based approach. Answers were then rated as "excellent response not requiring clarification," "satisfactory requiring minimal clarification," satisfactory requiring moderate clarification," or "unsatisfactory requiring substantial clarification."Of the 10 answers given by the chatbot, none received an "unsatisfactory" rating with the majority either requiring minimal (5) or moderate (4) clarification. While many answers required nuanced clarification, overall, answers tended to be unbiased and evidence-based, even when presented with controversial subjects.The chatbot does an excellent job of providing basic, evidence-based answers to patient FAQs prior to TKA. These data were presented in a manner that will be easily comprehendible by most patients and may serve as a useful clinical adjunct in the future.

Oxidative stress mediates associations between preoperative psychosocial phenotype and pain-related outcomes at 6 months following total knee arthroplasty: a longitudinal cohort study.

OBJECTIVE: Greater preoperative depression, anxiety, and pain catastrophizing are associated with more severe long-term pain following total knee arthroplasty (TKA). In a secondary analysis of previously reported data, we tested the hypothesis that these associations are mediated by oxidative stress (OS). DESIGN: A mixed between/within-subjects longitudinal cohort design. SETTING: A single academic medical center. SUBJECTS: Osteoarthritis patients (n = 91; 62.6% female) undergoing unilateral TKA. METHODS: We assessed depression, anxiety, and catastrophizing, as well as markers of central sensitization (widespread pain, temporal summation of pain) preoperatively. Blood samples were then obtained immediately prior to intraoperative tourniquet placement for quantification of in vivo biomarkers of systemic OS, F2-isoprostanes and isofurans. Post-TKA pain intensity (numeric rating scale worst pain [NRS], McGill Pain Questionnaire-2 [MPQ-2]) and function (PROMIS Pain Interference) were assessed at 6 months following TKA. RESULTS: Greater preoperative depression, catastrophizing, and widespread pain were associated with higher intraoperative combined OS (F2-isoprostanes+isofurans/2), which was in turn associated with higher post-TKA pain intensity and worse function (P < .05). All preoperative phenotype predictors except anxiety were correlated positively with post-TKA pain and/or function (P < .05). Bootstrapped mediation analyses revealed significant (P < .05) indirect (mediated) effects of depression (NRS Worst Pain, MPQ-2, PROMIS Pain Interference), anxiety (MPQ-2, PROMIS Pain Interference), and catastrophizing (PROMIS Pain Interference) on adverse long-term post-TKA outcomes via elevated OS. Central sensitization-related predictors demonstrated only direct effects (P < .05) on post-TKA outcomes that were independent of OS mechanisms. CONCLUSIONS: Results suggest that the adverse impact of depression, anxiety, and pain catastrophizing on post-TKA pain and functional outcomes are mediated in part by elevated OS.

Central Sensitization: The Missing Link Between Psychological Distress and Poor Outcome Following Primary Total Knee Arthroplasty.

BACKGROUND: While preoperative psychological distress is known to predict risk for worse total knee arthroplasty (TKA) outcomes, distress may be too broad and nonspecific a predictor in isolation. We tested whether there are distinct preoperative TKA patient types based jointly on psychological status and measures of altered pain processing that predict adverse clinical outcomes. METHODS: In 112 TKA patients, we preoperatively assessed psychological status (depression, anxiety, and catastrophizing) and altered pain processing via a simple quantitative sensory testing protocol capturing peripheral and central pain sensitization. Outcomes (pain, function, opioid use) were prospectively evaluated at 6 weeks and 6 months after TKA. Cluster analyses were used to empirically identify TKA patient subgroups. RESULTS: There were 3 distinct preoperative TKA patient subgroups identified from the cluster analysis. A low-risk (LR) group was characterized by low psychological distress and low peripheral and central sensitization. In addition, 2 subgroups with similarly elevated preoperative psychological distress were identified, differing by pain processing alterations observed: high-risk centralized pain and high-risk peripheral pain. Relative to LR patients, high-risk centralized pain patients displayed significantly worse function and greater opioid use at 6 months after TKA (P values <.05). The LR and high-risk peripheral pain patient subgroups had similar 6-month outcomes (P values >.05). CONCLUSIONS: Among patients who have psychological comorbidity, only patients who have central sensitization were at elevated risk for poor functional outcomes and increased opioid use. Central sensitization may be the missing link between psychological comorbidity and poor TKA clinical outcomes. Preoperative testing for central sensitization may have clinical utility for improving risk stratification in TKA patients who have psychosocial risk factors.

Preoperative Predictors of Prolonged Opioid Use in the 6 Months After Total Knee Arthroplasty.

OBJECTIVES: Prolonged postoperative opioid use increases the risk for new postsurgical opioid use disorder. We evaluated preoperative phenotypic factors predicting prolonged postoperative opioid use. METHODS: We performed a secondary analysis of a prospective observational cohort (n=108) undergoing total knee arthroplasty (TKA) for osteoarthritis with 6-week and 6-month follow-up. Current opioid use and psychosocial, pain, and opioid-related characteristics were assessed at preoperative baseline. Primary outcomes were days/week of opioid use at follow-up. RESULTS: At 6 weeks, preoperative opioid use and greater cumulative opioid exposure, depression, catastrophizing, anxiety, pain interference, sleep disturbance, and central sensitization were significantly associated with more days/week of opioid use after controlling for contemporaneous pain intensity. Prior euphoric response to opioids were also significant predictors at 6 months. All 6-week predictors except anxiety remained significant after controlling for preoperative opioid use; at 6 months, cumulative opioid exposure, catastrophizing, pain interference, and sleep disturbance remained significant after this adjustment ( P <0.05). In multivariable models, a psychosocial factor reflecting negative affect, sleep, and pain accurately predicted 6-week opioid use (area under the curve=0.84). A combined model incorporating psychosocial factor scores, opioid-related factor scores, and preoperative opioid use showed near-perfect predictive accuracy at 6 months (area under the curve=0.97). DISCUSSION: Overall, preoperative psychosocial, pain-related, and opioid-related phenotypic characteristics predicted prolonged opioid use after total knee arthroplasty.

Assessing ChatGPT Responses to Common Patient Questions Regarding Total Hip Arthroplasty.

BACKGROUND: The contemporary patient has access to numerous resources on common orthopaedic procedures before ever presenting for a clinical evaluation. Recently, artificial intelligence (AI)-driven chatbots have become mainstream, allowing patients to engage with interfaces that supply convincing, human-like responses to prompts. ChatGPT (OpenAI), a recently developed AI-based chat technology, is one such application that has garnered rapid growth in popularity. Given the likelihood that patients may soon call on this technology for preoperative education, we sought to determine whether ChatGPT could appropriately answer frequently asked questions regarding total hip arthroplasty (THA). METHODS: Ten frequently asked questions regarding total hip arthroplasty were posed to the chatbot during a conversation thread, with no follow-up questions or repetition. Each response was analyzed for accuracy with use of an evidence-based approach. Responses were rated as "excellent response not requiring clarification," "satisfactory requiring minimal clarification," "satisfactory requiring moderate clarification," or "unsatisfactory requiring substantial clarification." RESULTS: Of the responses given by the chatbot, only 1 received an "unsatisfactory" rating; 2 did not require any correction, and the majority required either minimal (4 of 10) or moderate (3 of 10) clarification. Although several responses required nuanced clarification, the chatbot's responses were generally unbiased and evidence-based, even for controversial topics. CONCLUSIONS: The chatbot effectively provided evidence-based responses to questions commonly asked by patients prior to THA. The chatbot presented information in a way that most patients would be able to understand. This resource may serve as a valuable clinical tool for patient education and understanding prior to orthopaedic consultation in the future.

Diagnosis Dilemma, Culture-Negative Periprosthetic Hip Infection Versus Acute Gouty Arthritis: A Case Report.

CASE: We report the case of acute gouty arthritis mimicking infection in a 59-year-old woman who had an extensive history of periprosthetic joint infection (PJI) and multiple revisions. Initial laboratory testing, examination, and recency bias suggested recurrent PJI, but aspiration revealed an acute gout attack without superimposed infection. The patient's examination and serological markers improved off antibiotics, and she subsequently avoided an unnecessary revision surgery. CONCLUSION: Although rare, acute gouty arthritis should be considered in every patient, and complete workup should be performed, regardless of infectious or rheumatologic history.

2022 American Association of Hip and Knee Surgeons Symposium: Periprosthetic Joint Infection.

Periprosthetic joint infection (PJI) is the leading cause of failure in patients undergoing total joint arthroplasty. This article is a brief summary of a symposium on PJI that was presented at the annual AAHKS meeting. It will provide an overview of current technqiues in the prevention, diagnosis, and management of PJI. It will also highlight emerging technologies in this setting.

Dexamethasone Is Associated With a Statistically Significant Increase in Postoperative Blood Glucose Levels Following Primary Total Knee Arthroplasty.

Background: Dexamethasone has the potential to cause a transient increase in blood glucose levels. Recent evidence has suggested the potential for a linearly increased risk of periprosthetic joint infection beginning at blood glucose levels of ≥115 mg/dL and an optimal cutoff of 137 mg/dL. We designed the following study to determine (1) what percentage of our patients had postoperative day 1 (POD1) glucose levels above 137 mg/dL and (2) if the administration of dexamethasone further increased this risk. Methods: All primary total knee arthroplasties performed from 1998 to 2021 at our institution were identified and retrospectively reviewed. Patient demographics, dexamethasone administration, and perioperative glucose levels were recorded. Outcomes included POD1 glucose levels, infection rate, and all-cause reoperations and revisions. Results: The average POD1 glucose level for the entire cohort (n = 5353) was 138.7 mg/dL. The percentage of patients with a glucose level of 137 mg/dL or higher was significantly greater in patients that received dexamethasone (55.2% vs 37.7%; P < .0001). Significantly higher glucose levels were seen with dexamethasone administration in both diabetic (187.7 vs 173.4 mg/dL; P < .0001) and nondiabetic patients (137.7 vs 128.0 mg/dL; P < .0001). Dexamethasone use was associated with a nonstatistically significant increase in infection rates (1.7% vs 1.0%; P = .177). Conclusions: Administration of dexamethasone is associated with a statistically significant increase in POD1 glucose levels, regardless of diabetic status. Dexamethasone use should continue to be closely monitored given the potential risks of elevated postoperative glucose levels and the potential for periprosthetic infection.

Is cement mantle thickness a primary cause of aseptic tibial loosening following primary total knee arthroplasty?

BACKGROUND: Aseptic tibial loosening following primary total knee replacement is one of the leading causes of long-term failure. Cement mantle thickness has been implicated as a source of aseptic tibial loosening. Therefore, the following study was designed to determine (1) what is the cement mantle thickness in patients that develop aseptic tibial loosening, and (2) is there a difference in cement mantle thickness based on the interface of failure? METHOD: This retrospective cohort included 216 patients revised for aseptic tibial loosening. Patient demographics, operative data, and clinical outcomes were recorded. A preoperative radiographic assessment was performed to determine the interface of failure and the thickness of the cement mantle using the Knee Society Radiographic Evaluation System zones. RESULTS: The average patient age was 65 years and body mass index was 33.7 kg/m2. 203 patients demonstrated radiographic failure at the implant-cement interface and 13 patients demonstrated failure at the cement-bone interface. The average cement mantle thickness of each radiographic zone for the entire cohort on the AP and lateral views was 4.4 and 4.5 mm, respectively. The average cement mantle thickness of patients that developed failure at the implant-cement interface was significantly greater than patients that failed at the cement-bone interface in each radiographic zone (p < 0.001). CONCLUSIONS: Patients that develop implant loosening at the cement-bone interface were noted to have a significantly decreased cement mantle compared to patients that failed at the implant-cement interface. Methods for decreasing tibial implant loosening should likely focus on improving the fixation at the implant-cement interface.

Trends in Total Knee Arthroplasty Cementing Technique Among Arthroplasty Surgeons-A Survey of the American Association of Hip and Knee Surgeons Members.

BACKGROUND: Aseptic loosening persists as one of the leading causes of failure following cemented primary total knee arthroplasty (TKA). Cement technique may impact implant fixation. We hypothesized that there is variability in TKA cement technique among arthroplasty surgeons. METHODS: A 28-question survey regarding variables in surgeons' preferred TKA cementation technique was distributed to 2,791 current American Association of Hip and Knee Surgeons (AAHKS) members with a response rate of 30.8% (903 respondents). Patterns of responses were analyzed by grouping respondents by their answers to certain questions including cementing technique, tibial cement location, and femoral cement location. RESULTS: A total of 73.5% reported performing at least 7 of 8 of the highest consensus techniques, including vacuum mixing (79.9%), using two bags (76.1%), tibial implant first (95.2%), single-stage cementing (96.9%), compression of the implants in extension (91.7%), and use of a tourniquet (84.3%). Medium and high viscosity cement was most commonly used (37.9 and 37.8%, respectively). Finger pressurization was most common (76.1%) compared to a gun (29.8%). There were 26.5% of respondents performing 6 or fewer of the most common majority techniques and seemed to perform other less common techniques (eg, use of a single bag of cement, trialing or closure prior to cement curing, and heating to accelerate cement curing). Cement was most commonly applied to the entire bone and implant surface on both the tibia (46.4%) and femur (47.7%), leaving much variation in the remaining cement application location responses. DISCUSSION: There appears to be variability in cemented TKA technique among arthroplasty surgeons. There were 26.5% of respondents performing less of the majority techniques and also performed other additional low-response rate techniques. Further studies that look at the impacts of variation in techniques on outcomes may be warranted. Our study demonstrates the need for defining best practices for cement technique given the substantial variability identified.

Perioperative oxidative stress predicts subsequent pain-related outcomes in the 6 months after total knee arthroplasty.

ABSTRACT: Total knee arthroplasty (TKA) is effective for pain reduction in most patients, but 15% or more report unsatisfactory long-term pain outcomes. We tested whether oxidative stress (OS) related to extended tourniquet application during TKA and subsequent ischemic reperfusion (IR) contributed to adverse post-TKA pain outcomes. Blood samples were obtained in 91 patients with osteoarthritis (63% female) undergoing TKA before tourniquet placement (T1), 45 minutes after tourniquet inflation (T2), and 15 minutes after tourniquet removal (T3). Plasma levels of F 2 -isoprostanes and isofurans, the most specific measures of in vivo OS, were quantified. Pain intensity and function were assessed at baseline and again at 6 weeks and 6 months after TKA. Results indicated that higher Combined OS (F 2 -isoprostanes + isofurans/2) at T1 baseline and larger increases in Combined OS from T1 to T2 were associated with higher baseline-corrected past 24-hour worst and average pain intensity (numeric rating scale) and higher past week McGill Pain Questionnaire-2 total scores at 6-month follow-up ( P 's < 0.05). Increases in Combined OS from T1 to T3, which should most directly capture OS and IR injury related to tourniquet use, were not associated with short-term or long-term post-TKA pain outcomes. Longer ischemia duration was unexpectedly associated with lower baseline-corrected pain intensity at 6-month follow-up. Combined OS was not linked to functional outcomes at either follow-up. Elevated perioperative OS seems to exert small but significant adverse effects on long-term post-TKA pain outcomes, although this OS seems unrelated to IR injury associated with extended tourniquet use.

Location of Initial Closed Reduction Attempt Significantly Increases Cost and Length of Stay in Total Hip Arthroplasty.

Background: Prosthetic hip dislocation remains one of the most frequent complications following total hip replacement. Dislocations are predominantly managed by a closed reduction in the emergency department (ED) or the operating room (OR). This study aimed to evaluate how the location of an initial closed reduction attempt impacts a patient's course of care including length of stay (LOS) and cost of care. Material and methods: A retrospective chart review was performed on all patients presenting to a single ED with a unilateral prosthetic hip dislocation from 2009 to 2019. A total of 108 patients were identified. Data collected included patient demographics, ED/hospital course, and hospital charges. Results: Seventy-four patients (69%) had initial reduction attempted in the ED (65/74, 88% were successful), while 34 patients (31%) went directly to OR (100% successful with closed reduction). Failed closed reduction in ED or direct to OR resulted in a greater LOS and rate of placement to a skilled nursing facility following discharge. Median hospital charges for successful ED reduction were $6,837, while failed ED closed reduction or direct to OR resulted in median charges of $27,317 and $20,481, respectively. Conclusion: Many patients successfully underwent closed reduction in the ED, and there was no difference in complications, independent of where the reduction was first performed. Patients undergoing reduction in the OR had greater LOS and cost of care, independent of whether a reduction attempt was performed and failed in the ED, than those successfully reduced in the ED.

Preoperative Predictors of Complex Regional Pain Syndrome Outcomes in the 6 Months Following Total Knee Arthroplasty.

This prospective observational study evaluated preoperative predictors of complex regional pain syndrome (CRPS) outcomes in the 6 months following total knee arthroplasty (TKA). Participants were n = 110 osteoarthritis patients (64.5% female) undergoing unilateral TKA with no prior CRPS history. Domains of negative affect (depression, anxiety, catastrophizing), pain (intensity, widespread pain, temporal summation of pain [TSP]), pain interference, sleep disturbance, and pro-inflammatory status (tumor necrosis factor-alpha [TNF-a]) were assessed preoperatively. CRPS outcomes at 6-week and 6-month follow-up included the continuous CRPS Severity Score (CSS) and dichotomous CRPS diagnoses (2012 IASP criteria). At 6 months, 12.7% of participants met CRPS criteria, exhibiting a "warm CRPS" phenotype. Six-week CSS scores were predicted by greater preoperative depression, anxiety, catastrophizing, TSP, pain intensity, sleep disturbance, and TNF-a (P's < .05). Provisional CRPS diagnosis at 6 weeks was predicted by higher preoperative TSP, sleep disturbance, and TNF-a (P's < .05). CSS scores at 6 months were predicted by more widespread and intense preoperative pain, and higher preoperative TSP, pain interference, and TNF-a (P's < .01). CRPS diagnosis at 6 months was predicted only by more widespread and intense pain preoperatively (P's < .05). Risk for CRPS following TKA appears to involve preoperative central sensitization and inflammatory mechanisms. Preoperative negative affect is unlikely to directly influence long-term CRPS risk. PERSPECTIVE: This article identifies preoperative predictors of CRPS features at 6 months following total knee arthroplasty, including more widespread pain and higher pain intensity, temporal summation of pain, pain interference, and tumor necrosis factor-alpha levels. Findings suggest the importance of central sensitization and inflammatory mechanisms in CRPS risk following tissue trauma.

Cruciate Substituting Implants in Primary Total Knee Arthroplasty.

The use of cruciate substituting (CS) total knee replacement has been increasing in popularity. There are numerous factors that have likely contributed to this expansion. The CS philosophy incorporates the ease of use commonly cited by advocates of the posterior stabilized (PS) total knee design with the bone preservation associated with a cruciate retaining (CR) design. The ultra-congruent highly cross-linked polyethylene liner increases stability without an appreciable change in wear. Furthermore, balancing the flexion and extension gaps does not require "titrating" the posterior cruciate ligament, improving the user-friendliness. This paper reviews the nuances of this implant design compared to PS and CR designs as well as provides surgical technique recommendations/considerations.

Oxidative stress is associated with characteristic features of the dysfunctional chronic pain phenotype.

ABSTRACT: The dysfunctional chronic pain (Dysfunctional CP) phenotype is an empirically identifiable CP subtype with unclear pathophysiological mechanisms that cuts across specific medical CP diagnoses. This study tested whether the multidimensional pain and psychosocial features that characterize the dysfunctional CP phenotype are associated broadly with elevated oxidative stress (OS). Measures of pain intensity, bodily extent of pain, catastrophizing cognitions, depression, anxiety, sleep disturbance, pain interference, and function were completed by 84 patients with chronic osteoarthritis before undergoing total knee arthroplasty. Blood samples were obtained at the initiation of surgery before incision or tourniquet placement. Plasma levels of F2-isoprostanes and isofurans, the most highly specific measures of in vivo OS, were quantified using gas chromatography/negative ion chemical ionization mass spectrometry. The results indicated that controlling for differences in age, sex, and body mass index, higher overall OS (mean of isoprostanes and isofurans) was associated with significantly (P < 0.05) greater pain intensity, more widespread pain, greater depressive symptoms and pain catastrophizing, higher pain interference, and lower function. OS measures were not significantly associated with sleep disturbance or anxiety levels (P >0.10). The results build on prior case-control findings suggesting that presence of a CP diagnosis is associated with elevated OS, highlighting that it may specifically be individuals displaying characteristics of the dysfunctional CP phenotype who are characterized by elevated OS. Clinical implications of these findings remain to be determined.

Total Joint Arthroplasty in Patients With Achondroplasia: Comparison of 90-Day Adverse Events and 5-Year Implant Survival.

BACKGROUND: Achondroplasia is the most common skeletal dysplasia, and total joint arthroplasty of the hip and/or knee in this patient population may present unique challenges. METHODS: All patients undergoing primary total hip or total knee arthroplasty (THA or TKA) for osteoarthritis in the 2010-2019 PearlDiver Mariner administrative database with least 90 days of postoperative follow-up were identified. Those with achondroplasia were matched 1:10 to patients without achondroplasia based on age, sex, and medical comorbidities. Ninety-day adverse events were assessed and compared using multivariate logistic regression. Five-year implant survival was determined and compared with Kaplan-Meier implant survival curves. Significance was set at P < .05. RESULTS: For THA, 150 patients with achondroplasia were matched to 1484 patients without and had significantly higher 90 days odds of surgical site infection (odds ratio [OR] = 3.49, P = .005) and readmission (OR = 2.35, P = .016). For TKA, 285 patients with achondroplasia were matched to 2828 without and had higher odds of aggregated any adverse event (OR = 1.52, P = .006) and transfusion (OR = 2.31, P < .001). Rates of the other studied adverse events were not significant for either set of the analyses. At 5 years, implant survival for those with and without achondroplasia was not different for those undergoing THA (P = .321) or TKA (P = .910). CONCLUSIONS: The present study represents the largest cohort of patients with achondroplasia undergoing total joint arthroplasty to date. Although several short-term adverse events had greater odds for those with achondroplasia, 5-year survival was not different for those with or without achondroplasia after THA or TKA, supporting confidence in longer term implant success.

Is preoperative genicular radiofrequency ablation effective for reducing pain following total knee arthroplasty? A pilot randomized clinical trial.

BACKGROUND AND OBJECTIVE: Although total knee arthroplasty (TKA) is an effective treatment for severe knee osteoarthritis (OA), a subset of patients experience significant postoperative pain and dissatisfaction. Several clinical trials support the analgesic benefits of genicular nerve radiofrequency ablation (GN-RFA) for non-operative knee OA, but only one prior trial has examined the effects of this intervention given preoperatively on postoperative outcomes following TKA, showing no analgesic benefit of cooled GN-RFA. The current study evaluated whether conventional thermal GN-RFA performed preoperatively resulted in significant improvements in pain and function following TKA. METHODS: This was a single-center, prospective, randomized, sham-controlled, double-blinded pilot trial in which patients received either conventional GN-RFA (n=30) or sham (n=30) between 2 and 4 weeks prior to their TKA. Baseline measures were obtained preprocedurally on the day of intervention, with follow-up outcomes obtained preoperatively on the day of surgery, and at 2 and 6 weeks postoperatively. RESULTS: Patients receiving GN-RFA showed no significant improvements relative to sham controls in the primary outcome, pain intensity at rest at 6-week follow-up. Secondary outcomes, including pain with ambulation and physical function, also showed no significant differences between groups at any follow-up assessment. CONCLUSIONS: Conventional GN-RFA of the superior lateral, superior medial, and inferior medial genicular nerves when performed prior to TKA did not provide clinically significant pain relief or improvement in functional status at 2 or 6 weeks postoperatively. TRIAL REGISTRATION NUMBER: NCT02947321.

Albumin and the fibrinogen-to-albumin ratio: Biomarkers for the acute phase response following total knee arthroplasty.

PURPOSE: Complications following total knee arthroplasty (TKA) lead to patient morbidity and cost. While acute phase reactants, such as c-reactive protein (CRP) and fibrinogen, have been used to predict complications following TKA, the extent and duration of changes in albumin levels following TKA are unknown. It is hypothesized that like CRP and fibrinogen, albumin, and the fibrinogen/albumin ratio (FAR) represent useful measures of the acute phase response (APR) following TKA. The purpose of this study was to describe the longitudinal course of albumin and FAR in healthy patients following TKA, relative to established biomarkers, and examine if the variance in albumin or FAR correlates with patient comorbidities. METHODS: This retrospective cohort study of patients undergoing TKA at a tertiary medical center. CRP, fibrinogen, and albumin values were collected pre- and post-operatively. An age-adjusted Charlson comorbidity index (CCI) was utilized as a measure of patient comorbidity status. RESULTS: The median preoperative albumin value was 4.3 g/dL, which dropped to 3.6 g/dL on postoperative day 1 following TKA. The albumin value returned to 93% of the baseline by postoperative week 2. The course of albumin inversely mirrored the course of CRP (r = -0.41). Median preoperative FAR was 0.087 g/L, which rose to 0.130 g/L by postoperative week 2 and returned to baseline by postoperative week 6. While preoperative FAR strongly correlated with postoperative week 2 values (r = 0.74), there was a weak positive correlation between age-adjusted CCI and pre-operative FAR (r = 0.24) in patients undergoing primary TKA. CONCLUSION: Albumin levels follow a predictable postoperative decline that inversely correlates with CRP in healthy patients following TKA. Given the low cost and abundance of laboratories offering albumin levels, direct albumin levels and/or albumin ratios such as FAR may be underutilized biomarkers for monitoring the APR following TKA.

Spinal Anesthetic Type and Independent Risk Factors for Postoperative Urinary Retention Following Total Joint Arthroplasty.

While risk factors for postoperative urinary retention (POUR) after total joint arthroplasty (TJA) have been identified, its association with type of spinal anesthetic has not yet been thoroughly investigated. Patients undergoing primary TJA between 2013-2018 were reviewed. From August 2013 to March 2016 bupivacaine was primarily given and from March 2016 through August 2018, most, although not all, received mepivacaine. Patient demographics as well as intraoperative data were recorded. One-thousand and fifty-four patients were included. POUR rates were not significantly different between groups (5.5% vs 6.1%, p = 0.675). Those who received mepivacaine had a significantly shorter length of stay (LOS) (1 vs. 2 days, p < 0.001). However, spinal anesthetic type was not significantly associated with either POUR or LOS after controlling for between-group differences. Older age (odds ratio [OR] 1.024 [95% confidence interval {CI}:1.000-1.049]; p = 0.049) and a history of benign prostatic hyperplasia or urinary incontinence/retention (OR 2.155 [95% CI:1.114-4.168]; p = 0.023) were confirmed as independent risk factors for POUR. (Journal of Surgical Orthopaedic Advances 29(4):225-229, 2020).