Sex Differences in Quadriceps Atrophy After Anterior Cruciate Ligament Tear.

BACKGROUND: Female athletes lag behind their male counterparts in recovery from anterior cruciate ligament (ACL) injury. Quadriceps muscle size and strength are crucial factors for regaining function after ACL injury, but little is known about how these metrics vary due to biological sex. HYPOTHESIS: Female patients have reduced vastus lateralis fiber cross-sectional area (CSA) and lower quadriceps strength after ACL injury than male patients. STUDY DESIGN: Cross-sectional study. LEVEL OF EVIDENCE: Level 4. METHODS: A total of 60 participants with recent ACL tear were evaluated for vastus lateralis muscle fiber CSA, isometric quadriceps peak torque, and quadriceps rate of torque development. Linear mixed models were fit to determine differences across sex and limb for each variable of interest. RESULTS: The female group averaged almost 20% atrophy between limbs (P < 0.01), while the male group averaged just under 4% (P = 0.05). Strength deficits between limbs were comparable between female and male groups. CONCLUSION: Immediately after ACL injury, female patients have greater between-limb differences in muscle fiber CSA but between-limb strength deficits comparable with those of male patients. CLINICAL RELEVANCE: These results indicate that the underpinnings of strength loss differ based on biological sex, and thus individual patients could benefit from a sex-specific treatment approach to ACL injury.

ASES and UCLA Are Responsive Patient-Reported Outcome Measures After Rotator Cuff Repair: A Systematic Review and Meta-analysis.

BACKGROUND: Multiple patient-reported outcome measures (PROMs) have been used to assess shoulder function, but it is unknown which are the most effective. PURPOSE/HYPOTHESIS: The purpose of this study was to report the multiple PROMs used after rotator cuff repair (RCR) and to compare the responsiveness between them. It was hypothesized that the Western Ontario Rotator Cuff PROM would be the most responsive and commonly used in patients undergoing RCR. STUDY DESIGN: Meta-analysis; Level of evidence, 4. METHODS: A systematic review was conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and PRISMA-Searching extension guidelines via PubMed/MEDLINE, Embase (Elsevier), and Web of Science (Clarivate). Patient and study characteristics were extracted. From the studies that met inclusion criteria for responsiveness analysis (≥2 PROMs reported, 1-year minimum follow-up, and pre- and postoperative PROM means and standard deviations reported), the authors compared the responsiveness between PROM instruments using effect size and relative efficiency (RE) if a PROM could be compared with another in ≥10 articles. RESULTS: A total of 252 studies met inclusion criteria (32,072 patients; mean age, 59.6 years; mean body mass index, 28.7; mean follow-up time, 27.8 months). Range of motion was reported in 131 (52%) studies and imaging findings were reported in 123 (49%) studies. There were 67 PROM instruments identified; the most commonly used were the American Shoulder and Elbow Surgeon (ASES) (n = 183; 73%), Visual Analog Scale (VAS) (n = 163; 65%), and Constant (n = 118; 47%) scores. The 3 PROMs with the highest effect sizes were the University of California, Los Angeles (UCLA) (2.51), Western Ontario Rotator Cuff (2.42), and ASES (2.00) scores. Overall, UCLA and ASES scores were the most responsive PROMs. The ASES PROM was more responsive than the VAS (RE, 1.70), Constant (RE, 2.76), Simple Shoulder Test (RE, 1.67), and Single Assessment Numeric Evaluation (RE, 2.14) scores. The UCLA PROM was more responsive than the ASES (RE, 1.03), VAS (RE, 3.66), Constant (RE, 1.72), and Simple Shoulder Test (RE, 1.66) scores. CONCLUSION: ASES and UCLA scores were the most responsive PROMs after RCR. The authors recommend widespread adoption of ASES and UCLA scores for clinical and research standardization; however, the UCLA PROM requires in-person range of motion and strength testing, which is a practical limitation and barrier to long-term follow-up.

Editorial Commentary: Utility of Patient-Reported Outcome Threshold Scores to Estimate Patient Satisfaction: 'Let's Ask the Patient!'

The reporting and analysis of patient-reported outcome measures have come a long way. Since the concept of the minimally clinically important difference was first introduced in 1989, threshold scores have grown to include substantial clinical benefit and patient acceptable symptomatic state (PASS). The initial motivation for developing these thresholds was rooted in separating clinical significance from statistical. These thresholds provide insight into the relationship between scores on patient-reported outcome measures (PROM) and patient-reported improvement and satisfaction. It follows that in order to evaluate PROM scores, the best method for deriving the threshold typically uses an anchor-based methodology, i.e., "ask the patient." Specifically, patients are asked how much change they've experienced and whether they consider their current state to be satisfactory. The responses to these questions are compared with the scores on PROMs to find outcome thresholds that best separate patients who reported no improvement from those who reported minimal improvement, substantial improvement, and satisfaction with their current state of health (PASS). The PASS is of particular importance as it speaks to what arguably matters most to patients-a satisfactory state of health. Finally, viewing the PASS from the perspective of variation from study to study rather than as a uniform classifier is needed to make use of the growing number of papers reporting these thresholds. Examining differences in PASS values across papers can provide insight into how well PROM scores reflect patient satisfaction in different settings.

Academic Faculty Demonstrate Weak Agreement in Evaluating Orthopaedic Surgery Residents.

Background: As objective metrics fade, subjective elements of orthopaedic surgery applicants carry increasing importance during recruitment. Academic orthopaedic surgeons believe they can select for high-performing orthopaedic residents. However, can they agree? The purpose of this study was (1) to analyze an academic orthopaedic surgery department to determine whether they agree on which residents performed best during residency and; (2) to correlate preresidency and intraresidency factors with postresidency evaluations of resident performance. Methods: With Institutional Review Board [IRB] approval, an orthopaedic surgery department completed surveys to evaluate residency performance for 10 years of graduated residents (2012-2022). Faculty determined (1) Post-Residency Class Rank (PRCR)-ranked from the highest (1) to lowest performing resident (5) relative to their class based on faculty perspective of performance-and (2) Rank List Score (RLS)-ranked based off the 5-point AOA SLOR used during recruitment interviews. RLS assessed how likely the department would have graduates in the program again based on residency performance. Free marginal Cohen's kappa statistics assessed faculty inter-rater agreement. Preresidency metrics (United States Medical Licensing Exam [USMLE] 1 and 2 scores, research publications, etc) were correlated with Orthopaedic In-Training Exam (OITE) scores, research productivity, American Board of Orthopaedic Surgery (ABOS) scores, and faculty-derived rankings. Linear regressions with forward variable entry (p < 0.05) were used to determine factors associated with excellent resident performance. Results: Eighteen of 25 faculty members (72%) provided survey responses evaluating 46 residents. Faculty agreed 37% and 38% of the time for PRCR (kappa 0.26) and RLS (kappa 0.23), respectively. Step 2 score was the only preresidency factor significantly associated with PRCR (p = 0.03, r2 = 0.15) and RLS (p = 0.02, r2 = 0.3). The only intraresidency factor significantly correlated with PRCR (p = 0.002, r2 = 0.50) and RLS (p = 0.01, r2 = 0.39) was PGY-4 OITE score. Conclusions: An academic orthopaedic surgery department is able to come to a consensus on evaluations of residency performance relative to peers in the same year of training (PRCR) and an objective standard (RLS). Step 2 and Post-Graduate Year (PGY)-4 OITE scores were the only preresidency and intraresidency factors with significant association to higher postresidency, faculty-derived performance scores. Level of Evidence: III.

Prevalence and Predictors of Postoperative Depression and Anxiety After Anterior Cruciate Ligament Reconstruction.

PURPOSE: Preoperative mood disorders influence postoperative outcomes after anterior cruciate ligament (ACL) reconstruction (ACLR), but the prevalence and risk factors associated with postoperative depression/anxiety development remain unknown. The purposes of this study were to quantify the prevalence of postoperative diagnoses of depression or anxiety following ACLR in patients under the age of 25 and assess the interplay between patient sex and ACL reoperation on the prevalence of a depression or anxiety diagnosis following ACLR. METHODS: ACLR patients under the age of 25 years old were identified in the Truven Healthcare Marketscan database. Patients with incomplete coverage +/- one year of the index surgical procedure were excluded. Patients were categorized by the presence of preoperative, postoperative, or no depression/anxiety using the International Classification of Diseases, Ninth Revision (ICD-9) codes. We compared patient demographics and reoperation rates following the index ACLR between the depression and anxiety categories. Additionally, logistic regression was fit to assess the interaction between sex and either ipsilateral or contralateral ACL surgery on postoperative depression/anxiety diagnosis. RESULTS: Of the 42,174 patients, 10.7% had a new depression/anxiety diagnosis after ACLR. Postoperative depression/anxiety was nearly twice as prevalent for females (F: 14.4%, M: 7.6%) despite having similar rates of secondary ACLR (F: 15.5%, M: 13.0%). Those with postoperative depression/anxiety had a considerably greater prevalence of reoperation (18.8%) than those without depression/anxiety (13.7%) and those with pre-existing preoperative depression/anxiety (12.9%). Sex and reoperation were independently associated with postoperative depression/anxiety diagnosis. CONCLUSION: Female sex and secondary ACL surgery are independently associated with an increased prevalence of postoperative depression/anxiety. Nearly one in seven young females are diagnosed with depression/anxiety after ACLR. Similarly, a greater proportion of patients who suffer a secondary ACL surgery are subsequently diagnosed with depression/anxiety. The orthopedic community must be cognizant of the increased risk of postoperative depression/anxiety for females and those who suffer a secondary ACL surgery, and screening for depression/anxiety in these at-risk populations with referrals to mental health professionals may be warranted.

Nutritional Laboratory Studies Prior to Total Knee Arthroplasty: Practice Versus Publication.

BACKGROUND: Recent emphasis has been placed on nutritional status assessment prior to total knee arthroplasty (TKA), including multiple American Academy of Orthopaedic Surgeons publications recommending specific laboratory studies; however, the frequency with which surgeons obtain these laboratory studies remains unclear. We sought to assess the incidence of ordering nutritional laboratory studies in the 90 days prior to TKA, utilizing data from a large administrative claims database. METHODS: With use of the PearlDiver database, we identified 557,670 patients undergoing primary TKA from 2011 to 2020 with a metabolic panel or blood cell count claim within 90 days prior to TKA. We then determined the incidence of prealbumin, transferrin, vitamin D, and zinc laboratory tests claimed 90 days prior to TKA. Associations between claims and the year of surgery, patient demographics, and clinical characteristics were assessed by comparing proportions and chi-square testing. RESULTS: Nutritional laboratory studies were infrequently claimed within 90 days prior to TKA, with studies for prealbumin being performed in 2.2% of patients; transferrin, 1.9%; vitamin D, 10.2%; and zinc, 0.2%. From 2011 to 2020, there was a moderate but steady increase in the proportion of patients with claims for prealbumin (change from 0.8% in 2011 to 3.4% in 2020; p < 0.001), transferrin (0.8% to 2.7%; p < 0.001), and vitamin D (7.6% to 9.4%; p < 0.001) laboratory tests but there was less of a change for zinc (0.1% to 0.2%; p < 0.001). There were weak-to-absent associations of age, gender, obesity, diabetes, and anemia with laboratory claims. CONCLUSIONS: Despite multiple publications and recommendations, nutritional laboratory studies are infrequently ordered prior to TKA. Although there has been a slight increase in the use of nutritional laboratory studies over the past decade, patient factors such as gender and obesity were not associated with this increase. Understanding current practice patterns may help target future areas for improvement. LEVEL OF EVIDENCE: Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

The Combination of Depression and Obesity was Associated with Increased Incidence of Subsequent Total Knee Arthroplasty.

OBJECTIVE: Compare the incidence of total knee arthroplasty (TKA) within the first 5 years after knee OA diagnoses between matched groups of individuals with or without comorbid diagnoses of obesity and/or depression. We hypothesized that the greatest incidence of TKA within 5 years of OA diagnosis would be in the cohort of individuals with combined obesity and depression. METHODS: The PearlDiver Mariner Ortho157 database was used to identify four cohorts of individuals with knee OA based on diagnosis codes that were matched by age, sex, and Charlson Comorbidity Index: a group without diagnoses associated with depression or obesity (Control), those with obesity but not depression (Obesity), those with depression but not obesity (Depression), and those with diagnoses of both obesity and depression (Depression+Obesity). The incidence of subsequent TKA within the first 5 years after the index OA diagnosis were compared between the four matched cohorts. RESULTS: Each cohort was comprised of 274,403 unique individuals (180,563 females, 93,840 males; age=55±7 y). The incidence of TKA was greatest for the Depression+Obesity group (11.9%) when compared to the Control group (8.3%, p<0.0001, RR=1.43 [95%CI:1.41,1.45]), the Obesity group (10.2%, p<0.0001, RR=1.13 [95%CI:1.11,1.14], p<0.0001) or Depression (7.8%, p<0.0001, RR=1.53 [95%CI:1.50,1.55], p<0.0001). CONCLUSION: The incidence of subsequent TKA was greatest for those with the combination of obesity and depression when compared to the Control group and those with individual diagnosis of obesity or depression.

Factors Associated With Long-Term Quadriceps Muscle Function After Surgical Fixation of Lower Extremity Fractures.

OBJECTIVE: The long-term performance of the quadriceps femoris muscle and physical function following surgical repair of a lower extremity fracture remains largely undefined. The purpose of this study was to investigate between-limb differences in quadriceps performance 12 months after surgical fixation of a lower extremity fracture. It was hypothesized that the injured limb would be significantly weaker, have a lower rate of torque development (RTD), and that there would be a reduced step-down performance compared to the uninjured limb 12 months after surgery. Additionally, this study sought to identify demographic, surgical, and psychological factors associated with poor quadriceps function 12 months after surgery. METHODS: Quadriceps performance was measured bilaterally in 95 participants (49 female), aged 42 (SD = 14.5) years, 12 months after surgical fixation of a lower extremity fracture. Isometric quadriceps strength and RTD were quantified using isometric dynamometry, and a timed step-down test was used to evaluate quadriceps performance. Independent predictor variables from the time of surgery were extracted from participants' medical records. Kinesiophobia was screened at the time of testing. Wilcoxon signed-rank tests and linear regression analyses were used to assess between-limb differences in quadriceps performance and to determine factors associated with quadriceps performance 12 months after surgery. RESULTS: Significant between-limb differences in each measure of quadriceps performance were identified (peak torque involved: 1.37 [0.71] Nm × kg-1; uninvolved: 1.87 [0.74] Nm × kg-1; RTD involved: 4.16 [2.75] Nm × kg-1 × s-1; uninvolved: 6.10 [3.02] Nm × kg-1 × × -1; and single-leg step-downs involved: 12.6 [5.0]; uninvolved: 21.7 [14.8]). Female biological sex, external fixation, and kinesiophobia at 12 months were associated with reduced after-surgery quadriceps performance outcomes. CONCLUSION: Quadriceps performance is impaired 12 months after surgical repair of a lower extremity fracture, particularly in female participants, in cases requiring external fixation, and in those with higher kinesiophobia 12 months after surgery. IMPACT: Because long-term quadriceps weakness negatively impacts functional mobility, targeted strengthening should be emphasized after surgical repair of lower extremity fracture.

Development and Validation of a Short-Form Version of the Western Ontario Shoulder Instability Scale (Short-WOSI).

BACKGROUND: Patient-reported outcome measures (PROMs) have transitioned from primarily being used as research instruments to becoming increasingly used in the clinical setting to assess recovery and inform shared decision-making. However, there is a need to develop validated short-form PROM instruments to decrease patient burden and ease incorporation into clinical practice. PURPOSE: To assess the validity and responsiveness of a shortened version of the Western Ontario Shoulder Instability Index (Short-WOSI) when compared with the full WOSI and other shoulder-related PROM instruments. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: This study was a secondary analysis of data collected as part of an institutional review board-approved, multicenter cohort of 1160 patients undergoing surgical stabilization for shoulder instability. The following PROMs were captured preoperatively and 2 years after surgery: WOSI, American Shoulder and Elbow Surgeons (ASES) score, the Single Assessment Numeric Evaluation (SANE), and 36-Item Health Survey (RAND-36). The cohort was split into 2 data sets: a training set to be used in the development of the Short-WOSI (n = 580) and a test set to be used to assess the validity and responsiveness of the Short-WOSI relative to the full WOSI, ASES, SANE, and RAND-36. RESULTS: The Short-WOSI demonstrated excellent internal consistency before surgery (Cronbach α = .83) and excellent internal consistency at the 2-year follow-up (Cronbach α = .93). The baseline, 2-year, and pre- to postoperative changes in Short-WOSI and WOSI were closely correlated (r > 0.90), with both demonstrating large effect sizes (Short-WOSI = 1.92, WOSI = 1.81). Neither the Short-WOSI nor the WOSI correlated well with the other PROM instruments before (r = 0.21-0.33) or after (r = 0.25-0.38) surgery. The Short-WOSI, WOSI, and SANE scores were more responsive than ASES and RAND-36 scores. CONCLUSION: The 7-item Short-WOSI demonstrated excellent internal consistency and a lack of floor or ceiling effects. The Short-WOSI demonstrated excellent cross-sectional and longitudinal construct validity and was similarly responsive over time as the full WOSI. Neither the Short-WOSI nor WOSI correlated with more general shoulder PROMs, underscoring the advantage of using instability-specific instruments for this population.

Comparison of Physical Therapy Utilization and Motion-Related Re-operations Between Isolated Anterior Cruciate Ligament and Multi-Ligament Knee Injuries.

The increased prevalence of postoperative arthrofibrosis after multi-ligament knee injuries (MLKI) compared to isolated anterior cruciate ligament (ACL) injuries has been proposed to be due, in part, to patient factors limiting physical therapy utilization. The purpose of this study was to compare demographic factors, pre- and postoperative physical therapy utilization, and the need for motion-restoring surgery between MLKI and ACL-injured patients. Using the PearlDiver Mariner 151 database, two cohorts matched by age and sex were identified using current procedural terminology (CPT) codes and included those age 16 or greater that underwent isolated ACL (n=3801) vs. MLKI reconstruction (n=3801). The number of pre- and postoperative physical therapy visits was recorded, as was the need for motion-restoring surgery (arthroscopic lysis of adhesions or manipulation under anesthesia). Demographic factors, physical therapy utilization, and the prevalence of motion-restoring surgery were compared between the MLKI and ACL groups using t-tests or chi-square tests, as appropriate. A significantly greater proportion of those with MLKI underwent subsequent motion-restoring surgery (MLKI=412/3081 (13.4%) vs. ACL=84/3081 (2.7%), p<0.001; odds ratio = 5.5 (95% CI: 4.3, 7.0), p<0.0001). Following surgery, less than half of those with MLKI that underwent subsequent motion-restoring surgery attended physical therapy, which was significantly lower than those who did not require motion-restoring surgery (p<0.0001). The prevalence of motion-restoring surgery was significantly greater after MLKI when compared to an isolated ACL injury. While the etiology of arthrofibrosis after MLKI is likely complex, the current results suggest that demographic factors and physical therapy utilization are not solely responsible for the increased risk of arthrofibrosis after MLKI.

Patients With Depression and/or Anxiety Having Arthroscopic Rotator Cuff Repair Show Decreased Number of Prescriptions and Number of Psychotherapy Sessions in the Year After Surgery.

PURPOSE: To determine whether the utilization of psychological treatments changes after arthroscopic rotator cuff repair (RCR) for patients with preoperative depression and/or anxiety. METHODS: The Truven Healthcare Marketscan database was used to identify patients who underwent arthroscopic RCR between January 2009 and December 2016. We included all patients with diagnosis codes associated with either depression or anxiety before RCR. Patients were excluded if they did not have complete insurance coverage for 1 year before or after surgery, or if they had arthroscopic RCR in the year before the index surgical procedure. We compared the proportion of patients with preoperative depression or anxiety who filled a prescription and had psychotherapy procedural codes in the year before and the year after arthroscopic RCR. RESULTS: A total of 170,406 patients who underwent RCR were identified, of which depression and/or anxiety was found in 46,737 patients (43.7% male). Of the 46,737 patients, 19.6% filled a prescription for a depression/anxiety medication at least once in the year before surgery. Of this subset of patients, 41.5% did not fill a prescription for depression or anxiety medication after surgery, whereas 32.6% continued medication use but demonstrated a median 30-day reduction in the number of days' worth of medication. Similarly, 13.1% of patients were attending psychotherapy sessions preoperatively, but 76.6% of those patients either stopped or reduced the amount of psychotherapy sessions in the year following RCR. CONCLUSIONS: The number of prescriptions and psychotherapy sessions decreased in the year after RCR for patients with preoperative diagnoses of depression and/or anxiety. LEVEL OF EVIDENCE: Level IV, case series.

Increased Effusion Synovitis for Those With a Dysregulated Inflammatory Response After an Anterior Cruciate Ligament Injury.

Introduction The progression to posttraumatic osteoarthritis (PTOA) after an anterior cruciate ligament (ACL) injury is likely multifactorial, involving biological, mechanical, and psychosocial factors. Following acute joint trauma, there appears to be a subset of patients that demonstrate a dysregulated inflammatory response. This pro-inflammatory phenotype, or "Inflamma-type," is characterized by an amplified pro-inflammatory response combined with a lack of attendant anti-inflammatory response and has been observed following both an ACL injury and an intra-articular fracture. The aims of this study were to: 1) compare magnetic resonance imaging (MRI)-measured effusion synovitis between those with vs. without a dysregulated inflammatory response, and 2) assess the correlations between effusion synovitis and synovial fluid concentrations of proinflammatory cytokines, degradative enzymes, and synovial fluid biomarkers of cartilage degradation. Methods A cluster analysis was previously performed with synovial fluid concentrations of biomarkers of inflammation and cartilage degradation from 35 patients with acute ACL injuries. Patients were then categorized into two groups: a pro-inflammatory phenotype ("Inflamma-type") and those with a more normal inflammatory response to injury (NORM). Effusion synovitis measured from each patient's preoperative clinical MRI scan was compared between the Inflamma-type and NORM groups using an independent, two-tailed t-test. In addition, Spearman's rho non-parametric correlations were calculated to evaluate the relationship between effusion synovitis and each of the synovial fluid concentrations of pro-inflammatory cytokines, degradative enzymes, and biomarkers of cartilage degradation and bony remodeling. Results Effusion synovitis was significantly greater for the Inflamma-type (10.9±3.8 mm) than the NORM group (7.4±4.4 mm, p=0.04, Cohen's d=0.82). Effusion synovitis significantly correlated with matrix metalloproteinase-3 (rho=0.63, p<0.001), matrix metalloproteinase-1 (rho=0.50, p=0.003), and sulfated glycosaminoglycan (rho=0.42, p=0.01). No other significant correlations were present. Conclusion Effusion synovitis was significantly greater for those that demonstrated a dysregulated inflammatory response after acute ACL injury than those with a more normal response to injury. Effusion synovitis was also found to significantly correlate with synovial fluid concentrations of degradative enzymes and a biomarker of early cartilage degradation. Future work is needed to determine if non-invasive methods, such as MRI or ultrasound, may accurately identify patients within this pro-inflammatory phenotype and whether this subset is more prone to more rapid PTOA changes after injury.

Leveraging Insurance Claims Data to Identify Risk Factors for Posttraumatic Osteoarthritis After Multiligament Knee Reconstruction.

BACKGROUND: The incidence of subsequent posttraumatic osteoarthritis (OA) diagnosis after surgery and the associated risk factors have been well reported after single-ligament anterior cruciate ligament (ACL) reconstruction; however, to date, the incidence of posttraumatic OA for those who have experienced multiligament knee injury (MLKI) has been reported only in relatively small, single-center studies. PURPOSE: To compare the incidence of OA diagnoses between patients with ACL injury versus patients with MLKI and to identify risk factors for OA diagnosis after MLKI. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: This study used the PearlDiver Mariner database, which contains insurance claims information on >151 million orthopaedic patients. We identified 2 cohorts for this study by using Current Procedural Terminology codes. The cohorts included patients between the ages of 16 and 60 who underwent either isolated ACL reconstruction (n = 114,282) or MLKI reconstruction (n = 3325) between July 1, 2010, and August 30, 2016. MLKI reconstruction was operationally defined as ACL reconstruction plus concurrent surgical treatment of ≥1 additional ligaments. Demographic factors, concomitant meniscal and cartilage procedures, and subsequent reoperation to restore motion were recorded, as was the incidence of knee OA diagnosis within 5 years of the index surgical procedure. OA incidence and demographic and surgical factors were compared (1) between ACL and MLKI groups and (2) between patients with MLKI either with or without OA diagnosis. RESULTS: A significantly greater proportion of patients with MLKI were diagnosed with knee OA within 5 years of surgery (MLKI = 299/3325 [9.0%] vs ACL = 6955/114,282 [6.1%]; P < .0001) (odds ratio [OR], 1.52; 95% CI, 1.35-1.72; P < .001). Factors associated with increased odds of OA diagnosis after MLKI included age ≥30 years (OR, 5.90), reoperation to restore motion (OR, 2.54), obesity (OR, 1.96), mood disorder diagnoses (OR, 1.85), partial meniscectomy (OR, 1.85), and tobacco use (OR, 1.72). Concomitant meniscal repair was protective against OA diagnosis (OR, 0.06). CONCLUSION: OA incidence was greater after MLKI reconstruction than after isolated ACL reconstruction. Potentially modifiable risk factors for OA after MLKI were identified and include obesity, tobacco use, depression, and the need for motion-restoring surgery.

Penalty for Switching Implants? Assessing the Learning Curve With a Collarless, Tapered Wedge Cementless Femoral Component.

Background: Surgeon learning curve associated with a tapered wedge femoral implant as measured by early femoral component subsidence and 90-day risk of reoperation was evaluated. Methods: The first 451 patients undergoing primary, cementless total hip arthroplasty by a single, fellowship-trained arthroplasty surgeon with a tapered wedge stem design were retrospectively reviewed. Early radiographic femoral component subsidence during the first 6 weeks postoperatively and 90-day reoperations was recorded. Results: When stratified by approach, there was no association between date of surgery and femoral component subsidence in the posterior approach (P-value for linear trend over time = 0.44). In the direct anterior approach, there was a significant association between date of surgery and early femoral component subsidence (P-value for linear trend over time = 0.01). For both approaches, there was an increase in implanted stem size relative to templated stem size over time (P < .01 and P = .03, respectively). There was no association between the date of surgery and risk of 90-day reoperation (P = .45). Conclusions: In a single surgeon's initial use of a tapered cementless wedge stem, early femoral component subsidence was not impacted by the surgeon's learning curve when the posterior approach was utilized. Although subsidence was associated with date of surgery in the direct anterior cohort, this was not associated with increased risk of 90-day reoperation. Should a surgeon adopt a new tapered-wedge stem, these findings suggest that the stem is forgiving both in relation to subsidence and 90-day reoperation risk when appropriate surgical technique is utilized.

Hemoglobinopathy is Associated With Total Hip Arthroplasty Indication Even Beyond Sickle Cell Anemia.

Background: The extent to which hemoglobinopathies other than sickle anemia (HbSS) are associated with hip osteonecrosis is unknown. Sickle cell trait (HbS), hemoglobin SC (HbSC), and sickle/ß-thalassemia (HbSßTh) may also predispose to osteonecrosis of the femoral head (ONFH). We sought to compare the distributions of indications for a total hip arthroplasty (THA) in patients with and without specific hemoglobinopathies. Methods: PearlDiver, an administrative claims database, was used to identify 384,401 patients aged 18 years or older undergoing a THA not for fracture from 2010 to 2020, with patients grouped by diagnosis code (HbSS N = 210, HbSC N = 196, HbSßTh N = 129, HbS N = 356). ß-Thalassemia minor (N = 142) acted as a negative control, and patients without hemoglobinopathy as a comparison group (N = 383,368). The proportion of patients with ONFH was compared to patients without it by hemoglobinopathy groups using chi-squared tests before and after matching on age, sex, Elixhauser Comorbidity Index, and tobacco use. Results: The proportion of patients with ONFH as the indication for THA was higher among those with HbSS (59%, P < .001), HbSC (80%, P < .001), HbSßTh (77%, P < .001), and HbS (19%, P < .001) but not with ß-thalassemia minor (9%, P = .6) than the proportion of patients without hemoglobinopathy (8%). After matching, the proportion of patients with ONFH remained higher among those with HbSS (59% vs 21%, P < .001), HbSC (80% vs 34%, P < .001), HbSßTh (77% vs 26%, P < .001), and HbS (19% vs 12%, P < .001). Conclusions: Hemoglobinopathies beyond sickle cell anemia were strongly associated with having osteonecrosis as the indication for THA. Further research is needed to confirm whether this modifies THA outcomes.

Association of Osteoarthritis and Functional Limitations With Cognitive Impairment Among Older Adults in the United States.

Objective: Given overlapping pathophysiology, this study sought to assess the association between osteoarthritis (OA), functional impairment, and cognitive impairment in the aging population. Methods: The National Health and Nutrition Examination Survey was used to identify participants >60 years of age. We analyzed multivariable associations of grouped participants that underwent cognitive function testing using linear and logistic regression, adjusting for sex, age, race, and ethnicity. Results: Of 2776 identified participants representing a population of 50,242,917, 40% did not report OA or functional limitations; 21% had OA but not functional limitations; 15% did not have OA but had functional limitations; 17% had OA and related functional limitations; and 7% had OA and non-arthritic functional limitations. OA was not independently associated with cognitive impairment. Contrarily, functional limitations were associated with cognitive impairment regardless of OA diagnosis. Discussion: Cognitive impairment is not associated with OA, but rather functional limitations, potentially guiding future intervention.

Synovial Fluid Inflammatory Profiles did not Differ between Isolated Anterior Cruciate Ligament and Multi-ligament Knee Injuries.

Objective and design: The purpose of this study was to compare synovial concentrations of pro- and anti-inflammatory cytokines between multiple-ligament knee injured (MLKI) and anterior cruciate ligament (ACL)-injured patients. Subjects: 14 patients with MLKI and 10 patients with isolated ACL injury. Methods: Synovial fluid was aspirated from the operative knee at the time of surgery and the concentrations of pro- and anti-inflammatory markers in the synovial fluid were determined. Structures injured, the time between injury and surgery, and demographic factors were collected. Linear regressions were used to determine the association between injury pattern and synovial inflammatory markers when controlling for age, BMI, and time between injury and surgery. Results: When adjusting for group differences in age, BMI and the time between injury and surgery, no group differences were detected (interferon gamma (p = 0.11), interleukin-1beta (IL-1b, p = 0.35), IL-2 (p = 0.28), IL-4 (p = 0.64), IL-6 (p = 0.37), IL-8 (p = 0.54), IL-10 (p = 0.25), IL-12p70 (p = 0.81), IL-13 (p = 0.31), and tumor necrosis factor-alpha (p = 0.90)). Conclusion: Synovial fluid inflammatory markers did not differ between MLKI and isolated ACL injuries. MLKIs have a greater prevalence of postoperative arthrofibrosis when compared to isolated ACL injuries; however, this may be due in part to factors other than the inflammatory status of the joint.

Pain Early After Anterior Cruciate Ligament Reconstruction is Associated With 6-Month Loading Mechanics During Running.

BACKGROUND: Anterior cruciate ligament reconstruction (ACLR) results in persistent altered knee biomechanics, but contributing factors such as pain or patient function, leading to the altered loading, are unknown. HYPOTHESIS: Individuals with worse self-reported pain after ACLR would have poorer biomechanics during running, and poor loading mechanics would be present in the ACLR limb compared with contralateral and control limbs. STUDY DESIGN: Cohort pilot study. LEVEL OF EVIDENCE: Level 3. METHODS: A total of 20 patients after ACLR (age, 18.4 ± 2.7 years; height, 1.7 ± 0.1 m; mass, 84.2 ± 19.4 kg) completed visual analog scale and Knee Injury and Osteoarthritis Outcomes Score (KOOS) at 1 and 6 months postsurgery. At 6 months postsurgery, patients underwent biomechanical testing during running. A total of 20 control individuals also completed running biomechanical analyses. Associations between patient outcomes and biomechanics were conducted, and differences in running biomechanics between groups were analyzed. RESULTS: KOOS pain score 1 month after surgery was associated with peak ACLR knee abduction moment (R2 = 0.35;P = 0.01). At 6-months, KOOS sport score was related to peak abduction moment in the ACLR limb (R2 = 0.23; P = 0.05). For change scores, the improvement in pain scores related to ACLR limb peak knee abduction moment (R2 = 0.55; P = 0.001). The ACLR limb had lower knee excursion, extension moments, and ground-reaction forces compared with the uninvolved and control limb. The uninvolved limb also had higher ground-reaction forces compared with the ACLR limb and control limb. CONCLUSION: These results suggest that patient-reported outcomes 1 and 6 months after surgery are associated with running mechanics 6 months after ACLR. Further, the underloading present in the ACLR limb and overloading in the uninvolved limb indicates greater need for running rehabilitation after ACLR. CLINICAL RELEVANCE: Understanding pain and how it may be linked to movement dysfunction is important for improving long-term outcomes.

Balancing after randomization in orthopedic trials: Are we even or even paying attention?

A cornerstone of evidence-based medicine is the randomized controlled trial (RCT). While randomization seeks to balance study groups on potential confounders, this is not always achieved. Especially in orthopedic research where RCTs are often of modest size, imbalances can exist and may be a significant issue. We sought to describe whether orthopedic RCTs assess balancing between study groups, use statistical hypothesis testing to compare baseline characteristics between groups, and have balanced baseline characteristics between groups. All RCTs from four leading orthopedic journals published between July 2019 and June 2020 were identified and those reporting original trial results reviewed for discussion of balancing, use of statistical significance testing to compare baseline characteristics, and patient reported outcome measures (PROMs) at baseline. Standardized mean differences of baseline PROMs were calculated to assess balancing. Of 86 orthopedic RCTs reviewed, 59 (69%) assessed balancing and 50 (58%) used statistical significance testing to compare baseline characteristics. Of 74 articles specifying a primary outcome, 33 (45%) used a PROM with 23 (70%) reporting baseline PROM values. Of these articles, 17 (74%) had a difference of less than 0.25 standard deviations (SDs) between groups, 4 (17%) had a difference of between 0.25 and 0.50 SDs, and 3 (13%) had a difference greater than 0.5 SDs. Orthopedic RCTs usually assess balancing after randomization though there is room for improvement with over half of articles using hypothesis testing to assess baseline differences as opposed to a measure of the magnitude of the difference.