Journal of Bone and Joint Surgery, American Volume最新文献

Background: The purpose of this study was to (1) perform the first analysis of bone-derived DNA methylation, (2) compare DNA methylation clocks derived from bone with those derived from whole blood, and (3) establish a relationship between DNA methylation age and 1-year mortality within the geriatric hip fracture population.

Methods: Patients ≥65 years old who presented to a Level-I trauma center with a hip fracture were prospectively enrolled from 2020 to 2021. Preoperative whole blood and intraoperative bone samples were collected. Following DNA extraction, RRBS (reduced representation bisulfite sequencing) libraries for methylation clock analysis were prepared. Sequencing data were analyzed using computational algorithms previously described by Horvath et al. to build a regression model of methylation (biological) age for each tissue type. Student t tests were used to analyze differences (Δ) in methylation age versus chronological age. Correlation between blood and bone methylation ages was expressed using the Pearson R coefficient.

Results: Blood and bone samples were collected from 47 patients. DNA extraction, sequencing, and methylation analysis were performed on 24 specimens from 12 subjects. Mean age at presentation was 85.4 ± 8.65 years. There was no difference in DNA extraction yield between the blood and bone samples (p = 0.935). The mean follow-up duration was 12.4 ± 4.3 months. The mortality cohort (4 patients, 33%) showed a mean ΔAgeBone of 18.33 ± 6.47 years and mean ΔAgeBlood of 16.93 ± 4.02 years. In comparison, the survival cohort showed a significantly lower mean ΔAgeBone and ΔAgeBlood (7.86 ± 6.7 and 7.31 ± 7.71 years; p = 0.026 and 0.039, respectively). Bone-derived methylation age was strongly correlated with blood-derived methylation age (R = 0.81; p = 0.0016).

Conclusions: Bone-derived DNA methylation clocks were found to be both feasible and strongly correlated with those derived from whole blood within a geriatric hip fracture population. Mortality was independently associated with the DNA methylation age, and that age was approximately 17 years greater than chronological age in the mortality cohort. The results of the present study suggest that prevention of advanced DNA methylation may play a key role in decreasing mortality following hip fracture.

Level of evidence: Prognostic Level I . See Instructions for Authors for a complete description of levels of evidence.

Background: Operative fires are rare but unforgettable events, with the potential for devastating outcomes. It is estimated that 650 operating room (OR) fires occur each year in the United States, with the use of electrocautery devices and polymethylmethacrylate (PMMA) as the primary ignition and fuel sources. There are several case reports of OR fires caused by PMMA and electrocautery in the literature, but, to our knowledge, no formal studies have been performed exposing the flammability of PMMA and how PMMA reacts to an electrocautery ignition source.

Methods: We studied the flammability of PMMA with electrocautery as an ignition source in a controlled laboratory setting. We used 2 different brands of PMMA, both with and without antibiotics. The PMMA was prepared according to the manufacturer's guidelines. In our model, which used a cadaveric leg, the PMMA was placed next to a femoral component that is used in total knee arthroplasty (TKA). Electrocautery was applied at 30-second intervals for a total of 15 minutes. Flammability was defined as any visualized spark or flame while using an electrocautery device. The heat resulting from the chemical reaction was recorded every 30 seconds with a thermal imaging camera (TIC). Video recording was used during the experiment to document the flammability events. A total of 108 tests were performed.

Results: PMMA with and without antibiotics proved to be flammable with the use of electrocautery. All flammability occurred within 7 minutes of combining the monomer and the powder. Increased flammability was seen with the use of antibiotic additives.

Conclusions: PMMA was found to be highly flammable in the initial curing period when exposed to electrocautery as an ignition source. When PMMA is ready for application, we recommend that an "electrocautery timeout" be performed, wherein the electrocautery device is removed from the operating field for a minimum of 7 minutes or until the PMMA has fully hardened.

Background: Subtrochanteric proximal femoral fractures are generally treated with cephalomedullary nail fixation. We aimed to compare outcomes of subtrochanteric fracture fixation using a single lag screw (Gamma3 nail, GN) or dual lag screw (INTERTAN nail, IN) device.

Methods: The primary outcome measure was mechanical failure, defined as lag screw cut-out or back-out, nail breakage, or peri-implant fracture. Secondary outcomes included reoperation for mechanical failure, deep infection, or nonunion, and technical predictors of mechanical failure. Adult patients (≥18 years of age) with a subtrochanteric proximal femoral fracture treated at a single center were retrospectively identified using electronic records. All patients who underwent fixation using either a long GN (November 2010 to January 2017) or IN (March 2017 to April 2022) were included. Medical records and radiographs were reviewed to identify operative complications.

Results: A total of 587 patients were included: 336 in the GN group (median age, 82 years; 73% female) and 251 in the IN group (median age, 82 years; 71% female). The risk of mechanical failure was 3-fold higher in the GN group (adjusted hazard ratio [aHR], 2.87; p = 0.010), with screw cut-out (p = 0.04) and back-out (p = 0.04) only observed in the GN group. We observed a greater risk of reoperation for mechanical failure in the GN group, but this did not achieve significance (aHR, 2.02; p = 0.16). Independent predictors of mechanical failure included varus malalignment of >5° for cut-out (aHR, 17.43; p = 0.012), a tip-to-apex distance of >25 mm for back-out (aHR, 9.47; p = 0.019), and shortening of >1 cm for peri-implant fracture (aHR, 5.44; p = 0.001).

Conclusions: For older patients with subtrochanteric and reverse-oblique femoral fractures, the dual lag screw design of the IN nail was associated with a lower risk of mechanical failure compared with the single lag screw design of the GN nail.

Level of evidence: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Background: Increasing U.S. health-care costs raise concerns regarding the sustainability of the U.S. health-care system, with the potential for negative effects on the mental and physical health of patients. Orthopaedic injuries often impose considerable financial burdens on patients and hospitals, but the trends in, and drivers of, costs remain unclear. This study evaluated the total expenditure and out-of-pocket (OOP) costs of patients with a lower-extremity (LE) fracture in the non-institutionalized U.S. population from 2010 to 2021.

Methods: A total of 3,016 participants with an LE fracture from the Medical Expenditure Panel Survey (MEPS) were propensity score matched with 15,080 MEPS participants with no LE fracture. Patients with an LE fracture were predominantly between 40 and 64 years old (43.2%), female (66.0%), and White (78.8%). Total expenditure and OOP costs were compared between the groups. A multivariable regression analysis was performed to identify factors that were associated with costs. Outcomes were adjusted on the basis of the 2022 Consumer Price Index.

Results: Patients with an LE fracture had greater total expenses than the control group ($20,230 [95% confidence interval (CI), $18,916 to $21,543] versus $10,678 [95% CI, $10,302 to $11,053]; p < 0.001) as well as greater OOP costs ($1,634 [95% CI, $1,516 to $1,753] versus $1,089 [95% CI, $1,050 to $1,128]; p < 0.001). Between 2010 and 2021, total expenses increased more for patients with an LE fracture than for the control group (101.2% versus 51.4%; p < 0.001), whereas OOP costs increased to a lesser degree in both groups (61.1% versus 44.5%; p = 0.17). In the LE fracture group, total expenditure was driven by inpatient care, office-based visits, and prescription costs, whereas OOP costs were driven by office-based visits, prescription costs, and "other" sources. Femoral fracture, hospitalization, and certain comorbidities were associated with higher total expenses. Hospitalization, uninsured status, and a higher income level were associated with increased OOP costs, whereas African American or Hispanic background and a lower educational level were associated with lower OOP costs.

Conclusions: An LE fracture was associated with considerable total expenditure and OOP costs, which increased disproportionately compared with general health-care costs over the past decade. Post-hospitalization care was the biggest driver of both total expenses and OOP costs. Due to limitations inherent to the MEPS database, the impact of financial burden on not only payers but also individuals and their medical decision-making remains unclear and requires further investigation.

Level of evidence: Economic Level III. See Instructions for Authors for a complete description of levels of evidence.

Background: The diagnosis of syndesmotic instability is challenging, and chronically unstable injuries can potentially lead to ankle arthritic degeneration. The objective of this cadaveric study was to utilize a 3-dimensional (3D) weight-bearing computed tomography (WBCT) distance mapping algorithm for the detection of subtle syndesmotic instability, induced by complete syndesmotic ligament sectioning and stressed by isolated axial load. We hypothesized that this algorithm would accurately detect subtle syndesmotic instability.

Methods: Nineteen matched pairs of through-the-knee cadaveric specimens (38 legs) were utilized. Specimens were mounted in a frame that allowed simulated axial weight-bearing (356 N). Specimens were scanned using cone-beam WBCT in the normal pre-injury state and after complete syndesmotic ligament sectioning. The deltoid ligament was kept intact, and no external rotational stress was applied. Syndesmotic incisura and lateral gutter distances were assessed and compared between pre-injury ipsilateral, contralateral, and injured states using a 3D WBCT distance mapping algorithm. The receiver operating characteristic (ROC) curve and area under the curve (AUC) were calculated for the comparison of syndesmotic distance measurements between injured specimens and controls. P values of <0.05 were considered significant.

Results: Overall, significantly increased distances were observed in injured specimens when compared with controls, with average relative syndesmotic widening in injured specimens of 16.9% (p = 0.0003), 11.3% (p = 0.0015), 6.4% (p = 0.0027), and 2.9% (p = 0.037) at the first 1, 3, 5, and 10 cm (proximal to the apex of the distal tibial articular surface), respectively. Widening was more pronounced in the anterior aspect of the syndesmosis, where the diagnostic accuracy was found to be highest at the first 1 and 3 cm of the syndesmotic incisura, with AUC values ranging from 80.9% to 83.0% (p < 0.0001) and with threshold diagnostic values of relative syndesmotic widening as low as 0.43 mm.

Conclusions: The newly proposed 3D WBCT distance mapping algorithm was able to accurately detect subtle syndesmotic instability in a cadaveric model of complete syndesmotic sectioning under isolated axial weight-bearing load. This algorithm needs to be further validated in patients with suspected traumatic syndesmotic instability.

Clinical relevance: This cadaveric study demonstrated high diagnostic accuracy of a 3D WBCT distance mapping algorithm to detect subtle syndesmotic instability when stressed with isolated axial loading and in the absence of deltoid injury. The future use of this algorithm in patients with suspected unilateral traumatic syndesmotic instability could hopefully optimize the diagnosis and treatment decision-making.

Background: Weight optimization methods in morbidly obese patients with a body mass index (BMI) of ≥40 kg/m 2 undergoing total knee arthroplasty (TKA) have shown mixed results. The purpose of this study was to evaluate the effect of perioperative use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) in patients with a BMI of ≥40 kg/m 2 undergoing primary TKA.

Methods: Using an administrative claims database, patients with morbid obesity undergoing primary TKA were stratified into GLP-1 RA use for 3 months before and after the surgical procedure (treatment group) and GLP-1 RA non-use (control group), and were matched on the basis of patient age, gender, diagnosis of type-2 diabetes mellitus, and Charlson Comorbidity Index (CCI). In addition, these groups were compared with a contemporaneous cohort of patients undergoing TKA with a BMI of 35.0 to 39.9 kg/m 2 . Outcomes including infection, complications, revision, and readmission were compared between the matched cohorts.

Results: There were significant decreases in the rates of 90-day periprosthetic joint infection (PJI) (1.0% compared with 1.8%; p = 0.037), any medical complications (10.6% compared with 12.7%; p = 0.033), pulmonary embolism (<0.4% compared with 0.6%; p = 0.050), and readmissions (5.3% compared with 8.9%; p < 0.001) in patients with a BMI of ≥40 kg/m 2 who were taking GLP-1 RA versus the control group who were not. There were no differences in the 2-year rates of surgical complications (p > 0.05) between these groups. Compared with obese patients (BMI of 35.0 to 39.9 kg/m 2 ), patients who had a BMI of ≥40 kg/m 2 and were taking a GLP-1 RA did not have increased rates of infection or 90-day or 2-year complications (p > 0.05).

Conclusions: GLP-1 RA administration for at least 90 days prior to and after primary TKA in patients with a BMI of ≥40 kg/m 2 was associated with reductions in the risks of 90-day PJI, any medical complications, and readmission. Additionally, the reduced complication rate that was achieved was similar to that of obese patients with a BMI of 35.0 to 39.9 kg/m 2 undergoing TKA. Randomized clinical trials are needed to define the true effect of these agents on clinical outcomes following TKA.

Level of evidence: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Background: Total joint arthroplasty (TJA) is increasingly being performed as an outpatient (i.e., same-day discharge) procedure. Postoperatively, orthostatic hypotension or pain-related tachycardia can lead to concerns regarding the hemoglobin (Hgb) level of the patient prior to discharge. The purpose of this study was to prospectively assess the reliability and accuracy of, and patient and nurse satisfaction with, postoperative noninvasive hemoglobin (nHgb) monitoring compared with an invasive serum hemoglobin (iHgb) laboratory draw in the outpatient TJA setting.

Methods: We prospectively enrolled 200 patients undergoing outpatient unilateral TJA, of whom 157 were ultimately included in our analysis (94 hips, 63 knees). Postoperatively, both nHgb and iHgb values were obtained at a mean of 36 minutes apart. Surveys were completed by patients and nurses. The strength of the agreement between the 2 Hgb monitoring methods was evaluated with use of the Bland-Altman 95% limits of agreement, concordance correlation coefficient (CCC), and intraclass correlation coefficient (ICC). Receiver operating characteristic curve analyses were performed to investigate the ability of nHgb monitoring to predict an iHgb of <11.2 g/dL (the 5th-percentile iHgb value).

Results: The mean preoperative iHgb was 14.2 ± 1.1 g/dL. The mean postoperative iHgb and nHgb values were 13.3 ± 1.5 and 13.3 ± 1.2 g/dL, respectively. The Bland-Altman 95% limits of agreement were -3.2 and +3.1 g/dL, indicating that 95% of patients' iHgb values are expected to fall between these limits relative to the nHgb value of the patient. The CCC and ICC were both 0.33. An nHgb cutoff value of <12.7 g/dL had 100% sensitivity and 67% specificity for detecting an iHgb of <11.2 g/dL. Patients reported less pain with the nHgb test than with the iHgb test (mean pain score, 0.0 versus 1.8; p < 0.001), and 97% of patients preferred the nHgb test. Following the nHgb test, 73% of responding patients and 83% of responding nurses were "somewhat more reassured" to "significantly more reassured" about same-day discharge.

Conclusions: Routine nHgb testing can rapidly screen patients undergoing outpatient TJA for acute anemia prior to discharge. With an nHgb of <12.7 g/dL, there was perfect sensitivity and 67% specificity for detecting an iHgb of <11.2 g/dL. Most patients and nurses felt more reassured about same-day discharge after nHgb monitoring.

Level of evidence: Diagnostic Level II . See Instructions for Authors for a complete description of levels of evidence.

Background: Previous research has underscored the benefits of geriatrician consultation in improving outcomes for older patients undergoing hip fracture repair, highlighting enhanced functional outcomes and reduced morbidity. However, the impact of geriatrician care in outcomes for patients undergoing elective total joint arthroplasty (TJA) has yet to be described. We aimed to determine whether preoperative or postoperative geriatrician involvement was associated with differences in the length of hospital stay and emergency department (ED) visits after TJA.

Methods: This retrospective cohort study screened the medical records of patients ≥65 years of age undergoing primary elective TJA in a network of tertiary hospitals. Geriatrician consultations occurring within a period spanning 90 days before to 90 days after TJA were recorded. Bivariate analysis and multivariable regression models were used to assess the relationship between receiving these consultations and changes in the length of stay and ED visits.

Results: A total of 16,076 patients undergoing primary TJA were included. Of these surgical procedures, 9,677 (60.2%) were total knee arthroplasties and 6,087 (37.9%) were total hip arthroplasties; 1,416 (8.8%) of cases had geriatrician visits. Patients had lower odds of requiring postoperative ED visits when they had at least 1 geriatrician appointment within the week preceding an arthroplasty (odds ratio [OR], 0.97 [95% confidence interval (CI), 0.68 to 0.99]; p = 0.005). This effect was most notable for 65-year-old patients (OR, 0.66 [95% CI, 0.45 to 0.98]).

Conclusion: This study reports promising evidence supporting the benefits of perioperative geriatrician visits on TJA outcomes. Preoperative visits were shown to be associated with decreased odds of ED visits after TJA in patients for up to 90 days postoperatively. Thus, geriatrician involvement in elective TJAs has the potential to improve outcomes and reduce morbidity and costs for patients and reduce costs for surgeons and institutions.

Level of evidence: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.