Comparison of Two Previously Validated Risk Assessment and Prediction Tool Models in Extended Length of Stay Patients Following Total Hip Arthroplasty.

INTRODUCTION: Previous studies have attempted to validate the risk assessment and prediction tool (RAPT) in primary total hip arthroplasty (THA) patients. The purpose of this study was to: (1) identify patients who had an extended length of stay (ELOS) following THA; and (2) compare the accuracy of two previously validated RAPT models. METHODS: We retrospectively reviewed all primary THA patients from 2014 to 2021 who had a completed RAPT score. Youden's J computational analysis was used to determine the LOS where facility discharge was statistically more likely. Based on the cut-offs proposed by Oldmeadow and Dibra, patients were separated into high- (O: 1 to 5 versus D: 1 to 3), medium- (O: 6 to 9 versus D: 4 to 7), and low- (O: 10 to 12 versus D: 8 to 12) risk groups. RESULTS: We determined that a LOS of greater than two days resulted in a higher chance of facility discharge. In these patients (n = 717), the overall predictive accuracy (PA) of the RAPT was 79.8%. The Dibra model had a higher PA in the high-risk group (D: 68.2 versus O: 61.2% facility discharge). The Oldmeadow model had a higher PA in the medium-risk (O: 78.7 versus D: 61.4% home discharge) and low-risk (O: 97.0 versus D. 92.5% home discharge) groups. CONCLUSION: As institutions continue to optimize LOS, the RAPT may need to be defined in the context of a patient's hospital stay. In patients requiring a LOS of greater than two days, the originally established RAPT cut-offs may be more accurate in predicting discharge disposition.

Revision rate following unipolar versus bipolar hemiarthroplasty.

INTRODUCTION: There has been much debate on use of bipolar or unipolar femoral heads in hemiarthroplasty for the treatment of femoral neck fractures. The outcome of these implants should be studied in the America Joint Replacement Registry (AJRR). METHODS: All primary femoral neck fractures treated with hemiarthroplasty between January 2012 and June 2020 were searched in the AJRR. All cause-revision of unipolar and bipolar hemiarthroplasty and reasons for revision were assessed for these patients until June of 2023. RESULTS: There were no differences in number and reason for all cause revisions between unipolar and bipolar hemiarthroplasty (p = 0.41). Bipolar hemiarthroplasty had more revisons at 6 months postoperatively (p = 0.0281), but unipolar hemiarthroplasty had more revisions between 2 and 3 years (p = 0.0003), and after 3-years (p = 0.0085), as analysed with a Cox model. Patients with older age (HR = 0.999; 95% CI, 0.998-0.999; p = 0.0006) and higher Charlson Comorbidity Index (HR = 0.996; 95% CI, 0.992- 0.999; p = 0.0192) had a significant increase in revision risk. CONCLUSIONS: We suggest that surgeons should consider using bipolar prosthesis when performing hemiarthroplasty for femoral neck fracture in patients expected to live >2 years post injury.

Prevention of Prosthetic Joint Infection Prior to Incision.

Prosthetic joint infection (PJI) remains a major cause of failure in total joint arthroplasty. This complication begets an increase in morbidity and mortality along with significant costs to the healthcare system. The use of prophylactic antibiotics has significant decreased the incidence of this complication. However, the incidence of PJI has not drastically decreased over the last 50 years. This review explores the history, current concepts, and future developments for prevention of PJI prior to incision in total joint arthroplasty.

Opioid Consumption and Mobilization in Staged Bilateral Total Joint Arthroplasty: Did We Learn Our Lesson the First Time?

BACKGROUND: In patients who require bilateral total hip arthroplasty (THA) or total knee arthroplasty (TKA), staged procedures are a reasonable option for treatment of bilateral osteoarthritis. We sought to determine whether perioperative outcomes differed between first and second total joint arthroplasty (TJA). METHODS: This was a retrospective review of all patients who underwent staged, bilateral THA or TKA between January 30, 2017, and April 8, 2021. All patients who were included underwent their second procedure within 1 year of the first. Patients were separated based on whether both their procedures took place before or subsequently after an institution-wide opioid-sparing protocol that was implemented on October 1, 2018. A total of 961 patients who underwent 1,922 procedures met the inclusion criteria for this study. For THA, 388 unique patients comprised 776 procedures, while 573 unique patients comprised 1,146 TKAs. Opioid prescriptions were prospectively documented on nursing opioid administration flowsheets and converted to morphine milligram equivalents (MME) for comparison. Activity measure scores for postacute care (AM-PAC) were used as a measurement of physical therapy progression. RESULTS: Hospital stays, home discharges, perioperative opioid usages, pain scores, and AM-PAC scores were not significantly different for the second THA or TKA compared to first procedure, regardless of timing in relation to the opioid-sparing protocol. CONCLUSION: Patients experienced similar outcomes following their first versus their second TJA. Limited opioid prescriptions following TJA do not negatively impact pain and functional outcomes. These protocols can safely be instituted to help mitigate the opioid epidemic. LEVEL III EVIDENCE: Retrospective Cohort Study.

Salvage Options for the Failed Total Knee Arthroplasty.

Total knee arthroplasty (TKA) is one of the most popular and successful procedures of the past century. However, as the number of TKAs continues to increase, the volume of revision surgeries also will increase. Although revision TKAs are often successful, adult reconstruction surgeons will likely continue to see patients with limited arthroplasty options after multiple failed revision TKAs. This raises the question of limb salvage versus transfemoral amputation as the final procedure option. It is important to review modern techniques for the patient who has undergone multiple revision TKAs with significant bone loss or chronic infection. These techniques include distal femur replacement, total femur arthroplasty, knee arthrodesis, and transfemoral amputation.

Vaping Trends and Outcomes in Primary Total Joint Arthroplasty Patients: An Analysis of 21,341 Patients.

INTRODUCTION: The effect of vaping on outcomes after total joint arthroplasty (TJA) and its prevalence in this patient population remain unclear. The purpose of this study was twofold: (1) to investigate the trends of vaping in TJA patients compared with patients who underwent routine physical examination and (2) to examine the influence vaping has on outcomes after TJA. METHODS: Patients were classified as never vaped, former vape users, or whether they reported current vaping (CV). TJA patients were further classified based on whether they had no exposure to tobacco or vaping (NTNV), tobacco only (TO), both tobacco and vaping (BTV), or vaping only (VO). RESULTS: The TJA group exhibited a steady trend of patients with CV status (P = 0.540) while patients in the routine physical examination cohort demonstrated a significant upward trend in CV status (P = 0.015). Subanalysis of TJA patients revealed that those in the VO category had significantly higher mean surgical time (P < 0.001), length of stay (P = 0.01), and rates of readmission (P = 0.001) compared with all other subgroups. CONCLUSION: We found steady or increasing trends of electronic cigarette exposure in both groups over time. Additional efforts should be made to document electronic cigarette exposure for all patients.

The standardized exploration of the radial nerve during humeral shaft fixation reduces the incidence of iatrogenic palsy.

BACKGROUND: The purpose of this study is to determine if a standardized protocol for radial nerve handling during humeral shaft repair reduces the incidence of iatrogenic nerve palsy post operatively. METHODS: Seventy-three patients were identified who underwent acute or reconstructive humeral shaft repair with radial nerve exploration as part of the primary procedure for either humeral shaft fracture or nonunion. All patients exhibited intact radial nerve function pre-operatively. A retrospective chart review and analysis identified patients who developed a secondary radial nerve palsy post-operatively. In each case, the radial nerve was identified and mobilized for protection, regardless of whether the implant necessitated the extensile exposure. RESULTS: Fractures were classified according to AO/OTA guidelines and included 23 Type 12A, 11 Type 12B, and 3 Type 12C. Eight patients had periprosthetic fractures and 28 fractures could not be classified. All patients in the cohort were fixed with locking plates. Surgery was indicated for 36 patients with humeral nonunions and 37 patients with acute humeral shaft fractures. Of the 73 patients, 2 (2.7%) developed radial nerve palsy following surgery, one from the posterior approach and one from the anterolateral approach. Both patients exhibited complete recovery of radial nerve function by 6-month follow-up. No significant differences (p > 0.05) were found in any demographic or surgical details between those with and without radial nerve injury. CONCLUSIONS: Nerve exploration identification and protection leads to a low incidence of transient radial nerve palsy compared to the rate reported in the current literature (2.7% compared to 6-24%). Thus, radial nerve exploration and mobilization should be considered when approaching the humeral shaft for acute fracture and nonunion repairs. LEVEL OF EVIDENCE: Level III.

Short-term outcomes of thin highly cross-linked polyethylene liners in primary total hip arthroplasty.

INTRODUCTION: The use of thin highly cross-linked polyethylene (HXLPE) liners in total hip arthroplasty (THA) allows utilisation of larger femoral heads. However, concern surrounding postoperative complications remains. This study aims to investigate rates of revision and re-admission associated with thin HXLPE liners at short-term follow-up. METHODS: We retrospectively reviewed 3047 patients who underwent THA with a cementless modular acetabular implant with a 36-mm femoral head, and different thicknesses of HXPLE liners from 2011 to 2021. We identified 723 patients (23.7%) with a minimum 2-year follow-up and 206 patients (6.8%) with a minimum 5-year follow-up. Patients in the thin group (TG, n = 1020) received <5.1-mm liners with 52-mm size cups while patients in the non-thin group (NTG, n = 2027) received >5.1-mm liners with >52-mm size cups. Outcomes were compared using multi-variable logistic regressions while controlling for all significant demographic differences. RESULTS: We found no significant differences in re-admission (3.9% vs. 4.3%, OR 0.97; 95% CI, 0.63-1.49; p = 0.874) and revision (2.5% vs. 3.2%, OR 0.72; 95% CI, 0.41-1.26; p = 0.246) rates between groups. The difference in fracture rate between groups was not significant, but the 1 recorded acetabular fracture (5%) occurred in the NTG. Although the rate of liner exchange was lower in the TG (1.1%) compared to the NTG (2.3%), the difference was not statistically significant (OR 0.51; 95% CI, 0.24-1.05; p = 0.068). Liners were exchanged for liner wear in 1 hip (1%), aseptic reasons in 38 hips (66%), and peri-prosthetic joint infection in 19 hips (33%). CONCLUSIONS: Patients undergoing THA with a thin liner were not significantly predisposed to higher rates of revision surgery or poorer clinical outcomes at short-term follow-up when compared to those who received a thicker liner. Consequently, further long-term studies regarding the utility of thin HXLPE implants in reducing complications should be pursued.

Orthopedic Surgery Resident Development and Implementation of a Virtual High-School Mentorship Program During the COVID-19 Pandemic.

As the world continues to battle the COVID-19 pandemic, health care providers are committed to providing care not only to our patients but also to our community. Schools in New York City (NYC) went remote on March 15, 2020. This can prove detrimental to student development and education. Numerous leaders in education and public health have noted that the remote learning will further widen educational and income disparities in those from underserved and underrepresented areas. A group of orthopedic residents who attended NYC public schools and were current house staff at a major academic tertiary medical center in NYC developed and implemented a virtual high-school mentorship program. This program incorporated weekly lectures and discussions given by health care providers to students interested in health care from NYC public high schools. The goal of this program was to provide mentorship during the COVID pandemic to a high-school audience where greater than 80% of students are considered to be living below the poverty level. Although school is now back in session, these programs should be continued in person. It is the aim of the authors that other orthopedic residents and health care providers implement similar programs in their communities.

Intra-articular Distal Humerus Fractures: Parallel Versus Orthogonal Plating.

Background: Dual-plating osteosynthesis is the standard treatment for Orthopedic Trauma Association (OTA)-type 13-C distal humerus fractures. However, optimal plate position is debated. Purpose: The purpose of this study was to evaluate dual-plate positioning following intra-articular distal humerus fracture repair by comparing outcomes between patients plated in parallel and those plated orthogonally following open-reduction, internal-fixation (ORIF) of intra-articular distal humerus fractures. Methods: All OTA-type 13-C intra-articular distal humerus fractures treated operatively at our institution over a 10-year period were reviewed. Clinical outcomes and complications were compared between those plated in parallel and those plated orthogonally. Data were analyzed using independent-samples t-tests, Mann-Whitney U tests, chi-square tests, and Fisher's exact tests. Results: A total of 69 patients met inclusion criteria. Mean follow-up among this cohort was 19.3 months; 45 (64.8%) patients had orthogonal dual plating, and 24 (35.2%) had parallel plating. Groups did not differ with respect to demographics or duration of follow-up. Clinically, there were no significant differences in time to union, elbow arc of motion at any time point, or patient Mayo Elbow Performance Index (MEPI) scores at final follow-up. Furthermore, there were no differences in complications. Conclusion: Parallel and orthogonal plating following ORIF of distal humerus fractures with modern, contoured locking compression plates had similar outcomes in this study. This study represents the largest comparative series in the literature at the time of its writing. Both techniques may be considered when deciding on dual-plating technique for treating intra-articular distal humerus fractures.

Dual Mobility in Total Hip Arthroplasty.

Dual mobility designs in total arthroplasty allow for increased range of motion prior to impingement and dislocation. While valuable for reducing dislocation, dual mobility has its own unique complication profile that includes intraprosthetic dislocation, corrosion, and femoral notching. Despite these relatively rare complications, dual mobility articulations are valuable options for patients at higher risk of dislocation-both early and contemporary reports on dual mobility in total hip arthroplasty suggest that it can reduce the risk of dislocation without leading to unacceptable rates of complication or early revision. Cost analyses and longer follow-up studies on newer dual mobility designs will help determine the future of dual mobility in total hip arthroplasty.

Occupational Hazards of Orthopedic Surgery Exposures: Infection, Smoke, and Noise.

The orthopedic environment exposes surgeons and staff to infection, surgical smoke, and high levels of noise. It is helpful to understand how exposure increases the risk for adverse health consequences. Protective equipment, safety protocols, and instrument modification can reduce exposure to hazards. When modifications to practice are made, they must be evaluated to ensure they do not introduce new hazards or impede the use of instruments. Despite evidence of risk, protective measures are seldom employed in orthopedic practice. Wider implementation of protection for clinicians may not occur unless the same hazards are shown to impact patient outcomes.

Comparing Articulating Spacers for Periprosthetic Joint Infection After Primary Total Hip Arthroplasty: All-Cement Versus Real-Component Articulating Spacers.

BACKGROUND: There are a variety of methods available to treat periprosthetic joint infection (PJI), including 2-stage revision with the use of an antibiotic spacer. This study compares the outcomes of real-component (RC) and all-cement (AC) articulating spacers for total hip arthroplasty (THA) PJI treatment. METHODS: This multicenter retrospective study assessed all articulating spacers placed for THA PJI between April 2011 and August 2020. Patients were dichotomized based on spacer type (RC vs AC). RESULTS: One hundred four patients received articulating spacer constructs (RC group = 75, AC group = 29). Leg-length discrepancy was significantly greater in the AC group after the second stage (3.58 vs 12.00 mm, P = .023). There were no significant differences in reoperation rates following first-stage spacer placement (P = .752) and time to reimplantation (P = .127) between the groups. There were no significant differences in reinfection rates (RC group = 10.0%, AC group = 7.1%, P = 1.000) and reoperation rates following second-stage revision THA (RC group = 11.7%, AC group = 10.7%, P = 1.000). Hospital length of stay (in days) had a trend toward being shorter following the first (7.35 vs 11.96, P = .166) and second stage (3.95 vs 5.43, P = .107) for patients in the RC group. Patients in the RC group were more likely to be discharged home following the first (P = .020) and second (P = .039) stages. CONCLUSION: Given that there were no differences in reinfection and reoperation rates between the 2 spacer constructs, RC articulating spacers may provide a significant benefit for patient comfort during 2-stage exchange treatment of PJI while adding no increase in risk profile.

A Novel Machine Learning Predictive Tool Assessing Outpatient or Inpatient Designation for Medicare Patients Undergoing Total Knee Arthroplasty.

BACKGROUND: Removal of total joint arthroplasty from the inpatient-only list has created significant confusion regarding which patients qualify for an inpatient designation. The purpose of this study is to develop and validate a novel predictive tool for assessing who will be an outpatient vs inpatient after total knee arthroplasty (TKA). METHODS: A cohort of Medicare patients undergoing primary TKA between January 2018 and September 2019 were retrospectively reviewed. Baseline demographics and patient characteristics were obtained, and their distributions for outpatient (less than 2 midnights) and inpatient stay were assessed. Subsequently, a XGBoost machine learning model was trained using 80% of the TKA patients, and the remaining 20% of patients were involved in testing the model's performance in terms of accuracy and the average area under the receive operating characteristic curve. RESULTS: Eight hundred ninety-nine Medicare patients underwent TKA at our institution between January 2018 and September 2019. Of which, 625 patients had outpatients stays, and 274 qualified for inpatient designation. Significant associations were demonstrated between inpatient visits and the following factors: higher body mass index, increased age, better functional scores, multidimensional fatigue inventory, Charlson Comorbidity Index, American Society of Anesthesiologists score, female gender, cardiac history, and the Revised Cardiac Risk Index. The XGBoost model for predicting an inpatient or outpatient stay was 63.3% accurate, with area under the receive operating characteristic curve of 68.8%. CONCLUSIONS: Using readily available key baseline characteristics, functional scores, and comorbidities, this machine-learning model accurately predicts the probability of an "outpatient" vs "inpatient" stay after TKA in the Medicare population. body mass index, age, VR12 functional scores, and multidimensional fatigue inventory scores had the highest influence on this predictive model.

Cefazolin remains the linchpin for preventing acute periprosthetic joint infection following primary total knee arthroplasty.

AIMS: Despite recent literature questioning their use, vancomycin and clindamycin often substitute cefazolin as the preoperative antibiotic prophylaxis in primary total knee arthroplasty (TKA), especially in the setting of documented allergy to penicillin. Topical povidone-iodine lavage and vancomycin powder (VIP) are adjuncts that may further broaden antimicrobial coverage, and have shown some promise in recent investigations. The purpose of this study, therefore, is to compare the risk of acute periprosthetic joint infection (PJI) in primary TKA patients who received cefazolin and VIP to those who received a non-cephalosporin alternative and VIP. METHODS: This was a retrospective cohort study of 11,550 primary TKAs performed at an orthopaedic hospital between 2013 and 2019. The primary outcome was PJI occurring within 90 days of surgery. Patients were stratified into two groups (cefazolin vs non-cephalosporin) based on their preoperative antibiotic. All patients also received the VIP protocol at wound closure. Bivariate and multiple logistic regression analyses were performed to control for potential confounders and identify the odds ratio of PJI. RESULTS: In all, 10,484 knees (90.8%) received cefazolin, while 1,066 knees (9.2%) received a non-cephalosporin agent (either vancomycin or clindamycin) as preoperative prophylaxis. The rate of PJI in the cefazolin group (0.5%; 48/10,484) was significantly lower than the rate of PJI in the non-cephalosporin group (1.0%; 11/1,066) (p = 0.012). After controlling for confounding variables, the odds ratio (OR) of developing a PJI was increased in the non-cephalosporin cohort compared to the cefazolin cohort (OR 2.389; 1.2 to 4.6); p = 0.01). CONCLUSION: Despite the use of topical irrigant solutions and addition of local antimicrobial agents, the use of a non-cephalosporin perioperative antibiotic continues to be associated with a greater risk of TKA PJI compared to cefazolin. Strategies that increase the proportion of patients receiving cefazolin rather than non-cephalosporin alternatives must be emphasized. Cite this article: Bone Jt Open 2022;3(1):35-41.

Self-Reported Feelings of Disability Following Lower Extremity Orthopaedic Trauma.

BACKGROUND: Nearly 20% of Americans consider themselves disabled. A common cause of disability is unexpected orthopaedic trauma. The purpose of this current study, assessing common lower extremity trauma, is the following: to assess the prevalence of self-reported feelings of disability following these injuries, to determine if self-reported feelings of disability impact functional outcomes, and to understand patient characteristics associated with self-reported feelings of disability. METHODS: The functional statuses of patients with tibial plateau fractures and ankle fractures were prospectively assessed. Patient reported feelings of disability (acquired from validated functional outcome surveys), which were compared with overall patient-reported functional outcome and emotional status at each follow-up visit. Additionally, patient demographics were analyzed, to assess associations with feelings of disability. RESULTS: A total of 710 patients were included in our analysis. At short-term follow-up (3 months), a strong positive correlation existed between self-reported feelings of disability and worse functional outcomes (rs = 0.744, P < 0.001). At long-term follow-up (12-months), a strong positive correlation existed between self-reported feelings of disability and worse functional outcomes (rs = 0.741, P < 0.001). Self-reported feelings of disability were associated with increased age at both short-term (P = 0.015) and long-term (P = 0.003) follow-ups. At short-term follow-up, 41% of males and 59% of females self-reported feelings of disability (P < 0.001) No significant differences existed between genders at long-term follow-up (P = 0.252). Self-reported feelings of disability declined at each follow-up visit, from 48.1% at short-term follow-up to 22.1% at long-term follow-up. CONCLUSION: Self-reported feelings of disability, following lower extremity trauma, had strong positive correlations with worse outcomes. Orthopaedic trauma surgeons should be aware of the percentage of patients who feel disabled following lower extremity fractures, and know that this is associated with sub-optimal outcomes. LEVEL OF EVIDENCE: III.

Total knee arthroplasty is associated with greater immediate post-surgical pain and opioid use than total hip arthroplasty.

BACKGROUND: As greater emphasis is being placed on opioid reduction strategies and implementation of multimodal analgesia, we sought to determine whether immediate post-surgical opioid consumption was different between THA and TKA. METHODS: A single-institution total joint arthroplasty database was used to identify patients who underwent elective THA and TKA from 2016 to July 2019. Baseline demographic data, operative time (defined by incision time), and American Society of Anesthesiologist (ASA) class were collected. Morphine milligram equivalents (MME) were calculated and derived from prospectively documented nursing opioid administration events, while visual analog scale (VAS) scores represented pain levels, both of which were collected as part of our institution's standard protocols. Activity Measure for Post-Acute Care (AMPAC) was used to determine physical therapy progress. RESULTS: A total of 11,693 cases were identified: 5,909 THA (50.53%) and 5784 (49.47%) TKA. THA patients tended to be slightly younger (63.38 years, SD 11.61 years, vs 65.72 years, SD 9.56 years; p < 0.01) and have lower BMIs (28.92 kg/m2 vs 32.52 kg/m2; p < 0.01). THA patients had lower ASA scores in comparison to TKA patients (p < 0.01). Aggregate opioid consumption (93.76 MME vs 147.55 MME; p < 0.01) along with first 24-h and 48-h usage was significantly less for THA as compared to TKA. Similarly, mean pain scores (4.15 vs 5.08; p < 0.01) were lower for THA, while AMPAC mobilization scores were higher (20.88 vs 19.29; p < 0.01) when compared to TKA. CONCLUSION: THA patients reported lower pain scores and were found to require less opioid medication in the immediate post-surgical period than TKA patients.

Effect of Marital Status on Outcomes Following Total Joint Arthroplasty.

INTRODUCTION: The purpose of this study is to investigate whether the specific socioeconomic factor such as marital status has any effect on clinical outcomes and patient-reported outcome measures (PROMs) after primary total hip (THA) and knee (TKA) arthroplasty. MATERIALS AND METHODS: We retrospectively reviewed patients who underwent primary THA or TKA from January 2019 to August 2019 who answered all PROM questionnaires. Both THA and TKA patients were separated into two groups based on their marital status at the time of surgery (married vs. non-married). Demographics, clinical data, and PROMs (FJS-12, HOOS, JR, KOOS, JR, and VR-12 PCS&MCS) were collected at various time-periods. Demographic differences were assessed using chi-square and independent sample t tests. Clinical data and mean PROMs were compared using multilinear regressions while accounting for demographic differences. RESULTS: This study included 389 patients who underwent primary THA and 193 that underwent primary TKA. In the THA cohort, 256 (66%) patients were married and 133 (34%) were non-married. In the TKA cohort, there were 117 (61%) married patients and 76 (39%) non-married patients. Length of stay was significantly shorter for married patients in both the THA (1.30 vs. 1.64; p = 0.002) and TKA (1.89 vs. 2.36; p = 0.024) cohorts. Surgical-time, all-cause emergency department visits, discharge disposition, and 90-day all-cause adverse events (readmissions/revisions) did not statistically differ between both cohorts. Both HOOS, JR and KOOS, JR score improvements from baseline to 1-year did not statistically differ for the THA and TKA cohorts, respectively. Although VR-12 PCS (p = 0.012) and MCS (p = 0.004) score improvement from baseline to 1-year statistically differed for the THA cohort, they did not for the TKA cohort. CONCLUSION: Total joint arthroplasty may yield similar clinical benefits in all patients irrespective of their marital status. Although some PROMs statistically differed among married and non-married patients, the differences are likely not clinically significant. Surgeons should continue to assess levels of psychosocial support in their patients prior to undergoing TJA to optimize outcomes. LEVEL OF EVIDENCE: III, Retrospective Cohort Study.

Presence of back pain prior total knee arthroplasty and its effects on short-term patient-reported outcome measures.

PURPOSE: Back pain may both decrease patient satisfaction after TKA and confound outcome assessment in satisfied patients. Our primary objective was to determine whether preoperative back pain is associated with differences in postoperative patient-reported outcome measures (PROMs). METHODS: We retrospectively reviewed 234 primary TKA patients who completed PROMs preoperatively and 12 weeks postoperatively, which included a back pain questionnaire, the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) and the Forgotten Joint Score-12 (FJS-12). Cohorts were defined based on the severity of preoperative back pain (none, mild, moderate and severe) and compared. Demographics were compared using ANOVA and Chi-square analysis. Univariate ANCOVA analysis was utilized to compare PROMs while accounting for significant demographic differences. RESULTS: Both preoperative KOOS JR scores (none: 47.90, mild: 47.61, moderate: 44.61 and severe: 38.70; p = 0.013) and 12-week postoperative KOOS JR scores (none: 61.24, mild: 64.94, moderate: 57.48 and severe: 57.01; p = 0.012) had a statistically significant inverse relationship with regard to the intensity of preoperative back pain. Although FJS-12 scores at the 12-week postoperative period trended lower with increasing levels of preoperative back pain (p = 0.362), it did not reach statistical significance. Patients who reported severe back pain preoperatively achieved the largest delta improvement from baseline compared to those with lesser pain intensity (p = 0.003). Patients who had a 2-grade improvement in their back pain achieved significantly higher KOOS JR scores 12 weeks postoperatively compared to patients with either 1-grade or no improvement (63.53 vs. 55.98; p = 0.042). Both preoperative (47.99 vs. 41.11; p = 0.003) and 12-week postoperative (64.06 vs. 55.73; p < 0.001) KOOS JR scores were statistically higher for those who reported mild or no back pain pre-and postoperatively than those who reported moderate or severe back pain pre-and postoperatively. CONCLUSION: Knee pain and back pain both exert negative effects on outcome instruments designed to measure pain and function. Although mean improvement from pre- to postoperative KOOS JR scores for patients with severe pre-existing back pain was higher than their counterparts, this statistical difference is likely not clinically significant. This implies that all patients may experience similar benefits from TKA despite the presence or absence of back pain. Attempts to measure TKA outcomes using PROMs should seek to control for lumbago and other sources of body pain. Level of Evidence IIIRetrospective Cohort Study.