Femoral Neck Anteversion: Which Distal Femur Landmark Matters?

Background: Femoral neck anteversion has traditionally been measured by the angle between the distal femur posterior condylar axis (PCA) and a line drawn through the center of the femoral head and neck. While less common, the transepicondylar axis (TEA) has also been used to reference femoral neck anteversion. The purpose of this study was to compare femoral neck version of the PCA vs the TEA using computerized tomography (CT). Methods: A total of 1507 femoral CTs were included. Precise bony landmarks were established: lateral epicondyle, medial epicondyle, posteromedial condyle, posterolateral condyle, center of the femoral neck, and center of the femoral head. Femoral version was calculated between the head and neck axis and either the PCA or TEA. Differences between sex and ethnicity were evaluated. Results: The mean femoral anteversion was 12.7° ± 9.1° based on the PCA and 11.5° ± 7.9° based on the TEA (mean difference 1.2° ± 1.9°, P < .001). Males were less anteverted than females (9.8° ± 7.6° vs 13.5° ± 7.8°, P < .001). African Americans had less anteversion than other groups (8.1° ± 9.2° vs 11.5° ± 7.8°, P = .04), while Asians were more anteverted than other groups (12.1° ± 9.0° vs 11.2° ± 7.3°, P = .04). These values were referenced on the TEA. Conclusions: In this series of over 1500 femoral CT scans, the mean difference between anteversion measurements referencing the PCA and TEA was 1.2°. Native femoral version varied widely between gender and ethnic groups. Extreme femoral version, defined as <0° or >30°, was present in 11.8% of patients referencing the PCA.

Clinical outcomes and return to dance after total hip arthroplasty or hip resurfacing in professional dancers.

Aims: Professional dancers represent a unique patient population in the setting of hip arthroplasty, given the high degree of hip strength and mobility required by their profession. We sought to determine the clinical outcomes and ability to return to professional dance after total hip arthroplasty (THA) or hip resurfacing arthroplasty (HRA). Methods: Active professional dancers who underwent primary THA or HRA at a single institution with minimum one-year follow-up were included in the study. Primary outcomes included the rate of return to professional dance, three patient-reported outcome measures (PROMs) (modified Harris Hip Score (mHHS), Hip disability and Osteoarthritis Outcome Score for Joint Replacement (HOOS-JR), and Lower Extremity Activity Scale (LEAS)), and postoperative complications. Results: A total of 49 hips in 39 patients (mean age 56 years (SD 13); 80% female (n = 39)) were included. Mean follow-up was 4.9 years (SD 5.1). Of these 49 hips, 37 THAs and 12 HRAs were performed. In all, 96% of hips returned to professional dance activities postoperatively. With regard to PROMs, there were statistically significant improvements in mHHS, HOOS-JR, and LEAS from baseline to ≥ one year postoperatively. There were complications in 7/49 hips postoperatively (14%), five of which required revision surgery (10%). There were no revisions for instability after the index procedure. Two complications (5.4%) occurred in hips that underwent THA compared with five (42%) after HRA (p = 0.007), though the difference by procedure was not significantly different when including only contemporary implant designs (p = 0.334). Conclusion: Active professional dancers experienced significant improvements in functional outcome scores after THA or HRA, with a 96% rate of return to professional dance. However, the revision rate at short- to mid-term follow-up highlights the challenges of performing hip arthroplasty in this demanding patient population. Further investigation is required to determine the results of THA versus HRA using contemporary implant designs in these patients.

The John N. Insall Award: Does Melatonin Improve Subjective Sleep Quality After Total Knee Arthroplasty? A Randomized, Placebo-Controlled Trial.

BACKGROUND: Sleep disturbance is a common problem following total knee arthroplasty (TKA). The objective of this study was to determine if exogenous melatonin improves sleep quality following primary TKA. METHODS: A randomized, double-blind, placebo-controlled trial was conducted. A total of 172 patients undergoing unilateral TKA for primary knee osteoarthritis were randomized to receive either 5 mg melatonin (n = 86) or 125 mg vitamin C placebo (n = 86) nightly for 6 weeks. The primary outcome was the Pittsburgh Sleep Quality Index (PSQI) at 6 weeks and 90 days postoperatively. Secondary outcomes included 6-week and 90-day patient-reported outcome measures (PROMs), morphine milligram equivalents prescribed, medication compliance, adverse events, and 90-day readmissions. RESULTS: Mean PSQI scores worsened at 6 weeks before returning to the preoperative baseline at 90 days in both groups. There were no differences in PSQI scores between melatonin and placebo groups at 6 weeks (10.2 ± 4.2 versus 10.5 ± 4.4, P = .66) or 90 days (8.1 ± 4.1 versus 7.5 ± 4.0, P = .43). Melatonin did not improve the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement, Lower Extremity Activity Scale, Visual Analog Scale for pain, or Veterans Rand 12 Physical Component Score or Mental Component Score at 6 weeks or 90 days. Poor sleep quality was associated with worse PROMs at 6 weeks and 90 days on univariate and multivariable analyses, but melatonin did not modify these associations. There were no differences in morphine milligram equivalents prescribed, medication compliances, adverse events, or 90-day readmissions between both groups. CONCLUSIONS: Exogenous melatonin did not improve subjective sleep quality or PROMs at 6 weeks or 90 days following TKA. Poor sleep quality was associated with worse patient-reported function and pain. Our results do not support the routine use of melatonin after TKA.

A Telemedicine Solution to Minimize Unnecessary Emergency Department Transfers for Low-acuity Pediatric Orthopaedic Patients: A Model for Cost Minimization.

INTRODUCTION: Unnecessary emergency department (ED) transfers represent a notable source of excess costs and misutilization of healthcare resources, particularly with management of acute pediatric musculoskeletal injuries. This study used institutional data to create a model investigating the expected costs of a formal peer-to-peer telemedicine intervention designed to triage pediatric orthopaedic transfers, which we hypothesized would decrease healthcare costs by minimizing unwarranted ED-to-ED transfers. METHODS: In this retrospective modeling analysis, 350 pediatric orthopaedic trauma patients transferred to two in-network referral hospitals from outside facilities were identified and stratified into three groups representing how patients theoretically optimally could have been treated. Group 1 patients required ambulance transfer, group 2 patients required ED-level care but no ambulance transfer, and group 3 patients did not require ED-level care. Base case estimates for the proportions of patients in each group, probability of ambulance transport, and direct costs of care for each patient were derived from the database. A decision tree was developed to evaluate the expected costs of two triaging strategies: (1) transfer everyone or (2) triage first using e-consultation. Probabilistic sensitivity analyses were used to determine how the results of the decision analysis varied across ranges of cost and probability estimates. RESULTS: In the base case analysis, the telemedicine triage strategy was cheaper than the transfer-all strategy ($4,858 versus $6,610). In a 2-way sensitivity analysis comparing cost of a telemedicine visit and proportion of telemedicine triaged patients requiring ambulance transport, the telemedicine triage strategy remained cheaper than the transfer-all strategy across almost all possibilities for both variables. Additional potential benefits of triage before transfer, such as decreased length of time to completion of ED visit, cost to the family, and patient comfort and satisfaction, were not incorporated into this analysis. The potential for misdiagnosis related to telehealth and its potential costs were not included. DISCUSSION: We revealed substantial cost savings for the healthcare system from implementing a telehealth platform for peer-to-peer consultation when considering patient transfer for musculoskeletal trauma. Initial peer-to-peer e-consultations cost less than reflexive ambulance transfer in most situations. LEVEL OF EVIDENCE: Economic Level II.

The Risk Assessment and Prediction Tool (RAPT) Score Predicts Discharge Destination, Length of Stay, and Postoperative Mobility After Total Joint Arthroplasty.

BACKGROUND: Predicting an arthroplasty patient's discharge disposition, length of stay (LOS), and physical function is helpful because it allows for preoperative patient optimization, expectation management, and discharge planning. The goal of this study was to evaluate the ability of the Risk Assessment and Prediction Tool (RAPT) score to predict discharge destination, LOS, and postoperative mobility in patients undergoing primary total knee arthroplasty (TKA) and total hip arthroplasty (THA). METHODS: Primary unilateral TKAs (n = 9,064) and THAs (n = 8,649) performed for primary osteoarthritis at our institution from 2018 to 2021 (excluding March to June 2020) were identified using a prospectively maintained institutional registry. We evaluated the associations between preoperative RAPT score and (1) discharge destination, (2) LOS, and postoperative mobility as measured by (3) successful ambulation on the day of surgery and (4) Activity Measure for Post-Acute Care (AM-PAC) "6-Clicks" score. RESULTS: On multivariable analyses adjusting for multiple covariates, every one-point increase in RAPT score among TKA patients was associated with a 1.82-fold increased odds of home discharge (P < .001), 0.22 days shorter LOS (P < .001), 1.13-fold increased odds of ambulating on postoperative day 0 (P < .001), and 0.25-point higher Activity Measure for Post-Acute Care score (P < .001). Similar findings were seen among THAs. A RAPT score of 8 or higher was the most sensitive and specific cutoff to predict home discharge. CONCLUSION: Among nearly 18,000 TKA and THA patients, RAPT score was predictive of discharge disposition, LOS, and postoperative mobility. A RAPT score of 8 or higher was the most sensitive and specific cutoff to predict discharge to home. In contrast to prior studies of the RAPT score which have grouped TKAs and THAs together, this study ran separate analyses for TKAs and THAs and found that THA patients seemed to perform better than TKA patients with equal RAPT scores, suggesting that RAPT may behave differently between TKAs and THAs, particularly in the intermediate risk RAPT range.

Variability of pre-operative functional pelvic tilt in total hip arthroplasty patients.

PURPOSE: Pelvic tilt (PT) is important to consider when planning total hip arthroplasty (THA) due to its dynamic impact on acetabular orientation. The degree of sagittal pelvic rotation varies during functional activities and can be difficult to measure without proper imaging. The purpose of this study was to evaluate PT variation in the supine, standing, and seated positions. METHODS: A multi-centre cross-sectional study was performed that included 358 THA patients who had preo-perative PT measured from supine CT scan and standing and upright seated lateral radiographs. Supine, standing, and seated PT and associated changes between functional positions were evaluated. Anterior PT was assigned a positive value. RESULTS: In the supine position, mean PT was 4° (range, -35° to 20°), where 23% had posterior PT and 69% anterior PT. In the standing position, mean PT was 1° (range, -23° to 29°), where 40% had posterior PT and 54% anterior PT. In the seated position, mean PT was -18° (range, -43° to 47°), where 95% had posterior PT and 4% anterior PT. From standing to seated, the pelvis rotated posteriorly in 97% of cases (maximum 60°) with 16% of cases considered stiff (change ≤ 10°) and 18% of cases considered hypermobile (change ≥ 30°). CONCLUSION: Patients undergoing THA have marked PT variation in the supine, standing, and seated positions. There was wide variability in PT change from standing to seated, with 16% of patients considered stiff and 18% considered hypermobile. Functional imaging should be performed on patients prior to THA to allow for more accurate planning.

Geographic Variation in Knee Phenotypes Based on the Coronal Plane Alignment of the Knee Classification: A Systematic Review.

BACKGROUND: The extent of geographic variation in knee phenotypes remains unclear. The Coronal Plane Alignment of the Knee (CPAK) Classification proposes 9 coronal plane phenotypes based on constitutional limb alignment and joint line obliquity. This systematic review aims to examine differences in the distributions of CPAK types across geographic regions. METHODS: A systematic review of the literature was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies reporting distributions of knee phenotypes according to the CPAK classification for healthy and/or arthritic knees were included. RESULTS: There were 7 studies included, accounting for 5,964 knees in 3,917 subjects. Among healthy knees (n = 1,214), CPAK type II was the most common type in Belgium (39.2%), Taiwan (39.3%), and India (25.6%). Among arthritic knees (n = 2,804), CPAK type I was the most common in France (33.4%), India (58.8%), and Japan (53.8%), whereas CPAK type II was the most common in Australia (32.8%). The proportion of CPAK type I and II knees varied significantly across geographic regions among healthy (P < .01) and arthritic knees (P < .01). CONCLUSION: Significant variation in CPAK distributions exists between countries. Further work is needed to delineate racial and sexual differences in CPAK types, which were not explored in this article. A better understanding of population-level variability in knee phenotypes may enable orthopaedic surgeons to offer a more personalized approach to knee arthroplasty.

Reasons and Risk Factors for Failed Same-Day Discharge After Primary Total Knee Arthroplasty.

BACKGROUND: As ambulatory total knee arthroplasty (TKA) becomes increasingly common, unplanned admission after surgery presents a challenge for the health care system. Studies evaluating the reasons and risk factors for this occurrence are limited. We sought to evaluate the reasons for unplanned admission after surgery and identify risk factors associated with this occurrence. METHODS: Patients registered in an institutional ambulatory joint arthroplasty program who underwent a TKA from 2017-2020 were retrospectively reviewed. The criteria for enrollment include candidates for unilateral TKA between the ages of 18 and 70 years, with a body mass index (BMI) of less than 35, and appropriate social and material support at home. Patients who had certain comorbidities including coronary artery disease, valvular heart disease, and opioid dependence were not eligible. A total of 274 patients who underwent TKA with planned same-day discharge (SDD) were identified in the medical record and reviewed. In this cohort, 140 patients (51.1%) were discharged on the day of surgery and 134 patients (48.9%) required a minimum 1-night admission. Demographics, comorbidities, and perioperative data were collected. Factors associated with failed SDD were identified using multivariate logistic regression. RESULTS: The most common reasons for failed SDD were failure to meet ambulation goals (25%) and logistical issues related to a late-day case (19%). Risk factors for failed SDD include general anesthesia (odds ratio (OR) 12.60, P = .047), procedure start time after 11:00 am (OR 5.16, P < .001), highest postoperative pain score >8 (visual analogue scale, OR 5.78, P = .001). Willingness to accept a higher pain threshold before discharge (visual analogue scale 4 to 10) was associated with successful SDD (OR 3.0, P < .001). Age and American Society of Anesthesiologists (ASA) classification were not associated with failed SDD. CONCLUSIONS: The most common reasons for failed SDD were related to logistical issues and postoperative mobilization. Risk factors for failed SDD involve case timing and pain control. Modifiable perioperative factors may play an important role in successful SDD after TKA.

A Systematic Review of Propensity Score Matching in the Orthopedic Literature.

Background: Propensity score matching (PSM) is a statistical technique used to reduce bias in observational studies by controlling for measured confounders. Given its complexity and popularity, it is imperative that researchers comprehensively report their methodologies to ensure accurate interpretation and reproducibility. Purpose: This systematic review sought to define how often PSM has been used in recent orthopedic research and to describe how such studies reported their methods. Secondary aims included analyzing study reproducibility, bibliometric factors associated with reproducibility, and associations between methodology and the reporting of statistically significant results. Methods: PubMed and Embase databases were queried for studies containing "propensity score" and "match*" published in 20 orthopedic journals prior to 2020. All studies meeting inclusion criteria were used for trend analysis. Articles published between 2017 and 2019 were used for analysis of reporting quality and reproducibility. Results: In all, 261 studies were included for trend analysis, and 162 studies underwent full-text review. The proportion of orthopedic studies using PSM significantly increased over time. Seventy-one (41%) articles did not provide justification for covariate selection. The majority of studies illustrated covariate balance through P values. We found that 19% of the studies were fully reproducible. Most studies failed to report the use of replacement (67.3%) or independent or paired statistical methods (34.0%). Studies reporting standardized mean differences to illustrate covariate balance were less likely to report statistically significant results. Conclusion: Despite the increased use of PSM in orthopedic research, observational studies employing PSM have largely failed to adequately report their methodology.

Ambulatory total hip arthroplasty: Causes for failure to launch and associated risk factors.

AIMS: The volume of ambulatory total hip arthroplasty (THA) procedures is increasing due to the emphasis on value-based care. The purpose of the study is to identify the causes for failed same-day discharge (SDD) and perioperative factors leading to failed SDD. METHODS: This retrospective cohort study followed pre-selected patients for SDD THA from 1 August 2018 to 31 December 2020. Inclusion criteria were patients undergoing unilateral THA with appropriate social support, age 18 to 75 years, and BMI < 37 kg/m2. Patients with opioid dependence, coronary artery disease, and valvular heart disease were excluded. Demographics, comorbidities, and perioperative data were collected from the electronic medical records. Possible risk factors for failed SDD were identified using multivariate logistic regression. RESULTS: In all, 278 patients were identified with a mean age of 57.1 years (SD 8.1) and a mean BMI of 27.3 kg/m2 (SD 4.5). A total of 96 patients failed SDD, with the most common reasons being failure to clear physical therapy (26%), dizziness (22%), and postoperative nausea and vomiting (11%). Risk factors associated with failed SDD included smokers (odds ratio (OR) 6.24; p = 0.009), a maximum postoperative pain score > 8 (OR 4.76; p = 0.004), and procedures starting after 11 am (OR 2.28; p = 0.015). A higher postoperative tolerable pain goal (numerical rating scale 4 to 10) was found to be associated with successful SDD (OR 2.7; p = 0.001). Age, BMI, surgical approach, American Society of Anesthesiologists grade, and anaesthesia type were not associated with failed SDD. CONCLUSION: SDD is a safe and viable option for pre-selected patients interested in rapid recovery THA. The most common causes for failure to launch were failing to clear physical thereapy and patient symptomatology. Risk factors associated with failed SSD highlight the importance of preoperative counselling regarding smoking cessation and postoperative pain to set reasonable expectations. Future interventions should aim to improve patient postoperative mobilization, pain control, and decrease symptomatology.Cite this article: Bone Jt Open 2022;3(9):684-691.

No Effect of Surgical Approach on Discharge Outcomes in Outpatient Total Hip Arthroplasty.

Background: The interest in ambulatory total hip arthroplasty (THA) has increased recently due to a national focus on value-based care and improved rapid recovery protocols. Purpose: We sought to determine if surgical approach had an effect on discharge outcomes in outpatient THA. Methods: We performed a retrospective cohort study examining patients who underwent unilateral THA at a single institution using a standardized perioperative care pathway who were discharged home within 24 hours. In total, we compared 106 patients who underwent THA using the direct anterior approach (ATHA) and 90 patients who underwent THA using the posterior approach (PTHA). Univariate and multivariable analyses were used to compare time to ambulation, length of surgery, readmissions, and 90-day complications. Results:Time to ambulation in the ATHA and PTHA groups was 3.9 hours and 4.1 hours, respectively, and time to discharge was 5.9 hours and 6.0 hours, respectively. Length of surgery was shorter in the ATHA group than in the PTHA group (78 minutes vs 86 minutes, respectively). Complications occurred in 3 patients (3%) in the ATHA group vs 4 patients (4%) in PTHA group. In both groups, early ambulation (within 5 hours) predicted earlier time to discharge. Surgical approach was not associated with time to ambulation or time to discharge on multivariable analysis. Conclusion: In this retrospective study, outpatient THA was feasible in a well-selected population of patients undergoing anterior or posterior approaches. Further study is warranted.

Multimodal Thromboprophylaxis in Patients With a History of Venous Thromboembolism Undergoing Primary and Revision Knee Arthroplasty.

Background: Patients with a history of venous thromboembolism (VTE) undergoing total knee arthroplasty (TKA) are at a high risk of postoperative VTE. Purpose: In this high-risk population, we sought to evaluate the safety and efficacy of multimodal thromboprophylaxis. The regimen consisted of discontinuation of procoagulant medications, VTE risk stratification, regional anesthesia, rapid mobilization, perioperative use of pneumatic compression devices, vigorous ankle dorsiflexion during the recovery period, and chemoprophylaxis tailored to the patient's risk of VTE. Methods: We conducted a retrospective chart review of 141 consecutive patients with a history of VTE who underwent 177 elective TKA procedures between 2005 and 2019 by 2 arthroplasty surgeons at a single institution. The patients had a history of deep venous thrombosis (DVT) (n = 127; 72%), pulmonary embolism (PE) (n = 20; 11%), or both (n = 30; 17%). Postoperative chemoprophylaxis included aspirin (n = 20; 11%), anticoagulation (n = 135; 77%), or a combination of aspirin and anticoagulation (n = 21; 12%). Complications within 120 days, including VTE events, wound complications, bleeding, and unplanned readmissions, were recorded, as was 1-year mortality. Results: Five patients (2.8%) developed symptomatic DVT (3 distal, 2 proximal), and 4 patients (2.3%) developed symptomatic PE. The most common postdischarge complications were wound infection (n = 6; 3.4%) and stiffness requiring manipulation under anesthesia (n = 5; 2.8%). There was 1 emergency room visit and 13 unplanned readmissions; 3 patients developed intra-articular hematomas or prolonged wound drainage and recovered uneventfully. All patients were alive 1 year after surgery. Conclusion: The findings of this retrospective study suggest that multimodal prophylaxis may be safe and effective in patients with a history of VTE undergoing primary and revision TKA. More rigorous study is warranted.

The Incidence of Pediatric Tibial Spine Fractures Is Greater and Peaks Later in Male Patients.

Purpose: To use government-curated databases to produce incidence estimates for pediatric tibial spine fractures (TSFs) by age and sex. This study also describes the relative frequency of operative versus nonoperative management for TSFs by age and sex. Methods: US Healthcare Cost and Utilization Project databases were used to identify cases of TSF among patients aged 7 to 18 years in the year 2016. Patient-linked deidentified data from New York, Maryland, and Florida were gathered from state databases, and repeat visits by the same patient were collapsed into individual records. TSF incidence was then calculated, with U.S. census data used to determine the number of children at risk. The proportion of cases treated nonoperatively was determined based upon procedural codes. Results: In New York, Florida, and Maryland, 185 cases of TSF were found. Male patients accounted for 69.7% of cases. Incidence peaked at 9.3 per 100,000 at age 14 years for male patients and at 3.4 per 100,000 at age 9 years for female patients. In total, 57.9% of TSF cases were treated nonoperatively. The overall incidence of TSF was 2.8 cases per 100,000 for people aged 7 to 18 years. Conclusions: This study confirms a difference in incidence by sex for pediatric TSFs, with male patients having a greater peak incidence that also occurs at an older age. Most cases in this study were treated nonoperatively. Clinical Relevance: Due to the relative infrequency of TSFs in the pediatric population, there is a limited understanding of the epidemiology and treatment of these fractures. The use of data from a large patient database may provide valuable epidemiologic information about this uncommon injury.

Predicting Total Knee Arthroplasty Outpatient Discharge: Surgeons versus Insurance Companies.

BACKGROUND: Insurance companies are increasingly making unilateral determinations of admission status for primary total knee arthroplasty (TKA). These determinations may differ from those based on surgeon-derived criteria for outpatient knee replacement. The goal of this study is to determine if insurance company determinations of outpatient status are as reliable as surgeon-derived criteria in predicting outpatient discharge after TKA. METHODS: We retrospectively reviewed 709 patients who were preoperatively authorized for outpatient TKA. Patients were stratified into 2 groups: "outpatient per surgeon" (appropriate for outpatient surgery per institutional protocols) or "outpatient per insurance" (appropriate for inpatient surgery per institutional protocols but denied inpatient status by insurance). The primary endpoint of this study was the conversion rate of outpatient to inpatient stay. Univariate logistic regression was performed to compare the odds of conversion to inpatient stay between outpatient per surgeon and outpatient per insurance procedures and other covariates. RESULTS: The cohort included 434 outpatient per insurance (61.2%) and 275 outpatient per surgeon (38.8%) patients. Surgeons accurately predicted outpatients' discharge 92.0% of the time, while insurance companies did so 81.3% of time (P < .001). Outpatient per insurance procedures (odds ratio [OR] 2.20, P = .003) and body mass index >35 kg/m2 (OR 1.82, P = .026) had higher odds of being converted to inpatient. Males had higher odds (OR 1.52, P < .001) of being discharged as outpatient. CONCLUSION: Determining inpatient versus outpatient status is a complex decision involving both clinical and social factors. Surgeons accurately predicted outpatient discharge 92% of the time. Moreover, outpatient per insurance procedures were twice as likely to be converted to inpatient status. Therefore, insurance companies should leave deciding admission status up to both the patient and surgeon.