Bone remodeling and cortical thinning distal to the femoral stem: a retrospective review.

INTRODUCTION: There is a paucity of information on the bone remodeling that occurs distal to the femoral stem following total hip arthroplasty as most previous studies have focused on proximal changes. In this study, we report the cortical thinning that occur distal to the femoral stem after primary total hip arthroplasty. METHODS: A retrospective review was performed at one institution over a 5-year period. 156 primary total hip arthroplasty procedures were included. The Cortical Thickness Index (CTI) was measured on both operative and non-operative hips at 1 cm, 3 cm and 5 cm below the prosthetic stem tip on anteroposterior radiographic images pre-operatively as well as at 6 months, 12 months and 24 months post-operatively. The difference in average CTI was measured using paired t-tests. RESULTS: There were statistically significant decreases in CTI distal to the femoral stem at 12 months and 24 months (-1.3% and -2.8%, respectively). Greater losses were seen in female patients, patients older than 75, and patients with BMI less than 35 at 6 months postoperative. There were no differences in CTI at any time point on the non-operative side. CONCLUSION: The current study demonstrates that patients undergo bone loss as measured by CTI distal to the stem in the first 2 years following total hip arthroplasty. Comparison to the contralateral non-operative side confirms that this change is greater than expected for the natural aging process. A greater understanding of these changes will help optimize post-operative management and direct future innovations in implant design.

The Relationship Between Posterior Tibial Slope and Pediatric Tibial Eminence Fractures.

BACKGROUND: Tibial eminence fractures are bony avulsions of the anterior cruciate ligament from its insertion on the intercondylar eminence. Numerous anatomic factors have been associated with anterior cruciate ligament injuries, such as posterior tibial slope, but there are few studies evaluating the association with tibial eminence fracture. PURPOSE: To compare posterior tibial slope of pediatric patients with and without tibial eminence fractures. We hypothesized that a steeper posterior tibial slope would be associated with tibial eminence fracture. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Patients who underwent surgical treatment of tibial eminence fracture were retrospectively identified between January 2000 and July 2021. Adults aged >20 years and those without adequate imaging were excluded. Controls without gross ligamentous or osseous pathology were identified. Descriptive information and Meyers and McKeever classification were recorded. Posterior tibial slope measurements were obtained by 2 independent orthopaedic surgeons twice, with measurements separated by 3 weeks. Chi-square tests and independent-samples t tests were used to compare posterior tibial slope and patient characteristics. Inter- and intrareviewer variability was determined via the intraclass correlation coefficient. RESULTS: A total of 51 patients with tibial eminence fractures and 57 controls were included. By sex, tibial eminence fractures occurred among 34 male and 17 female patients with a mean age of 10.9 years. The posterior tibial slope among those with tibial eminence fractures (9.7°) was not significantly greater than that of controls (8.8°; P = .07). Male patients with a tibial eminence fracture had significantly steeper slopes compared with controls (10.0° vs 8.4°; P = .006); this difference was not observed between female patients and female controls. Patients with a slope ≥1 SD above the mean (12.0°) had 3.8 times greater odds (95% CI, 1.3-11.6; P = .017) of having a tibial eminence fracture. Male patients with a posterior tibial slope >12° had 5.8 times greater odds (95% CI, 1.1-29.1; P = .034) of having a tibial eminence fracture compared with male controls. CONCLUSION: Male patients undergoing surgical fixation of a tibial eminence fracture had an increased posterior tibial slope as compared with case-controls. Increased posterior tibial slope may be a risk factor for sustaining a tibial eminence fracture, although the clinical significance of this deserves further investigation.

Insurance status is not a predictor of rotator cuff tear magnitude.

Background: Rotator cuff tear (RCT) chronicity is an important factor in considering treatment options and outcomes for surgical repair. Many factors may contribute to delayed treatment, including timely access to care due to insurance status. The purpose of this study was to evaluate the relationship between the magnitude of RCT on presentation and insurance status. We hypothesize that publicly insured patients will have a greater incidence of chronic RCTs and shoulder pathology on initial presentation. Methods: Retrospective chart review of patients undergoing RCT repair at an academic tertiary care institution from 2005 to 2019. Demographic data, including age, race, sex, and insurance carrier, were collected. Insurance carriers were categorized into public (Medicare and Medicaid) or private insurance coverage. Individual magnetic resonance imagings were then reviewed by a board-certified musculoskeletal radiologist for supraspinatus (SS), infraspinatus (IS), subscapularis, and biceps tendon tears, as well as acromioclavicular arthritis. In addition, rotator cuff atrophy was evaluated by the scapular ratio. Univariate analysis of variance and logistic regression analyses were used to compare demographics and rotator cuff pathology between those with Medicaid and Medicare, as well as between publicly and privately insured patients. Results: Of the 492 patients in this study, 192 had private insurance, and 300 had public insurance (Medicaid: 50 and Medicare: 250). Insurance status was not found to be associated with differences in RCTs between Medicare and Medicaid patients. Those with Medicaid or Medicare (public), presented more frequently with SS or IS atrophy (SS atrophy, P = .002; IS atrophy, P = .039) than those with private insurance. However, after adjusting for age, no significant differences in rotator cuff tendon tear or atrophy frequencies were found between insurance groups. Conclusions: Patients with private and public insurance tend to present with similar chronicity and magnitude of RCTs. Insurance status does not appear to influence timely access to surgical care for patients with RCTs at an academic medical center.

Impact of Cigarette Smoking on Re-operation and Revision Surgery after Femoral Neck Fracture Treatment.

INTRODUCTION: Smokers and nicotine users have a higher risk of femoral neck fracture non-union and prolonged time to fracture union. The impact of smoking resulting in revision surgery after fixation of femoral neck fractures, however, rarely has been studied. The aim of this retrospective study was to review if cigarette smoking had an influence on re-operation and revision after femoral neck fracture treatment. METHODS: Three groups of patients (Group 1: active smokers; Group 2: former smokers; and Group 3: non-smokers) who sustained a femoral neck fracture from January 2012 through August 2018 were included. Outcomes investigated included femoral neck fracture type, operative fixation type, fixation failure, and time interval between initial fixation and revision. RESULTS: A total of 1,452 subjects were identified (Group 1: 165 subjects; Group 2: 507 subjects; and Group 3: 780 subjects). In the male population, Groups 1 and 2 had higher rates of femoral neck fracture than Group 3. Twelve cases required revisions (Group 1: three cases (6%); Group 2: two cases (2%); Group 3: seven cases (4%)), with all but one revision within the first year following initial fixation. Group 1 patients tended to be younger than the other two groups. CONCLUSION: Smoking has a positive association with the risk of femoral neck fracture amongst active and former male smokers. This study concluded that active smokers have a higher risk of non-union compared with non-smokers or former smokers. Smoking history, especially heavy or long-term, should play a role in deciding which fixation construct type to use for femoral neck fractures.

A Comparison of Coronary Artery Stenosis Estimates Made by Forensic Pathologists and Medical Students.

Previous studies suggest cardiovascular pathologists are less accurate than noncardiovascular pathologists (e.g., clinical pathologists) in estimating the degree of coronary artery stenosis. To further investigate the effect of training on accurate estimation of coronary artery stenosis, we designed a study to compare the accuracy of estimates made by forensic pathologists versus medical students. Six forensic pathologists and twelve medical students each independently examined 24 images of coronary artery cross sections and gave an estimate of the degree of stenosis. When comparing all 24 images, the forensic pathologists had a median difference between the estimated percentage of stenosis and actual percentage of stenosis of -12.380 and the medical students had a median difference of -16.50 (p-value of 0.08542). In estimating the percentage of stenosis, training in forensic pathology does not guarantee significantly improved accuracy compared with medical students. Our study showed no consistent statistically significant difference between estimates given by forensic pathologists and by medical students.