Publications

Acute Compartment Syndrome (ACS) is one of the most devastating orthopedic conditions, affecting any of the body's many compartments, which, if sufficiently severe, may result in disability and amputation. Currently, intra-compartmental pressure measurements serve as the gold standard for diagnosing ACS. Diagnosing limbs at risk for ACS before irreversible damage to muscle and nerve is critical. Standard approaches for diagnosing impending compartment syndrome include clinical evaluation of the limb, such as assessment for "tightness" of the overlying skin, reduced pulses distally, and degree of pain, none of which are specific or sensitive. We have proposed a novel method to detect ACS via electrical impedance myography (EIM), where a weak, high-frequency alternating current is passed between one pair of electrodes through a region of tissue, and the resulting surface voltages are measured via a second pair. We evaluated the ability of EIM to detect early muscle ischemia in an established murine model of compression-induced muscle injury, where we collected resistance, reactance, and their dimensionless product, defined as Relative Injury Index (RII) during the study. Our model generated reproducible hypoxia, confirmed by Hypoxyprobe™ staining of endothelial regions within the muscle. Under conditions of ischemia, we demonstrated a reproducible, stable, and significant escalation in resistance, reactance, and RII values, compared to uninjured control limbs. These data make a reasonable argument for additional investigations into using EIM for the early recognition of muscle hypoperfusion and ischemia. However, these findings must be considered preliminary steps, requiring further pre-clinical and clinical validation.

BACKGROUND: Trauma is a leading cause of mortality and morbidity, disproportionately affecting low- and middle-income countries. Musculoskeletal trauma results in the majority of post-traumatic morbidity and disability globally. The literature has reported many performance indicators relating to trauma care, but few specific to musculoskeletal injuries.

STUDY OBJECTIVES: The purpose of this study was to establish a practical list of performance indicators to evaluate and monitor the quality and equity of musculoskeletal trauma care delivery in health systems worldwide.

METHODS: A scoping review was performed that identified performance indicators related to musculoskeletal trauma care. Indicators were organized by phase of care (general, prevention, pre-hospital, hospital, post-hospital) within a modified Donabedian model (structure, process, outcome, equity). A panel of 21 experts representing 45 countries was assembled to identify priority indicators utilizing a modified Delphi approach.

RESULTS: The scoping review identified 1,206 articles and 114 underwent full text review. We included 95 articles which reported 498 unique performance indicators. Most indicators related to the hospital phase of care (n = 303, 60%) and structural characteristics (n = 221, 44%). Mortality (n = 50 articles) and presence of trauma registries (n = 16 articles) were the most frequently reported indicators. After 3 rounds of surveys our panel reached consensus on a parsimonious list of priority performance indicators. These focused on access to trauma care; processes and key resources for polytrauma triage, patient stabilization, and hemorrhage control; reduction and immobilization of fractures and dislocations; and management of compartment syndrome and open fractures.

CONCLUSIONS: The literature has reported many performance indicators relating to trauma care, but few specific to musculoskeletal injuries. To create quality and equitable trauma systems, musculoskeletal care must be incorporated into development plans with continuous monitoring and improvement. The performance indicators identified by our expert panel and organized in a modified Donabedian model can serve as a method for evaluating musculoskeletal trauma care.

PURPOSE: One factor influencing the management of distal radius fractures is the functional status of the patient. The purpose of this study was to assess the agreement between patient and surgeon assessments of patient activity level in patients sustaining a distal radius fracture.

METHODS: Ninety-seven patients were included, with a mean age of 58.5 years (range, 18-92 years). Patients completed the International Physical Activity Questionnaire, a validated survey that provides a score of low, moderate, or high activity levels. Treating surgeons provided an independent assessment using the same scale. Agreement between patient and surgeon assessments was evaluated using a weighted kappa-statistic, with a secondary analysis using logistic regression models to assess odds of surgical treatment.

RESULTS: Interrater agreement between surgeons and patients demonstrated only "fair" agreement, with a kappa-statistic of 0.33. Predictive models showed that surgeons accurately identified 73% of "high activity" patients but failed to correctly identify more than 41% of patients rated as "moderate activity" or "low activity." There was a correlation between surgical intervention and increasing physical activity status as assessed by the surgeon; however, the magnitude of this effect was unclear (odds ratio, 2.14; 95% confidence interval, 1.07-4.30). This relationship was no longer significant after adjusting for age, Charlson comorbidity index, and fracture class. There was no association between surgical intervention and physical activity status when using the status provided by the patient.

CONCLUSIONS: Surgeon assessment of patient activity level does not have strong agreement with patients' independent assessment. Surgeons are most accurate at identifying "high activity level" patients but lack the ability to identify "moderate activity level" or "low activity level" patients.

CLINICAL RELEVANCE: Recognition of surgeon assessment of patient activity level as flawed can stimulate improved dialog between patients and physicians, ultimately improving the shared decision-making process.

PURPOSE: Radius and ulna fractures are among the most common fractures. These fractures are managed through operative or nonsurgical treatment, with varying implications in terms of cost and functional outcome. There are few studies that robustly characterize the management of distal radius fractures (DRFs) in the United States during the COVID-19 pandemic. Furthermore, this has not been studied among the Medicare patient population, who are particularly vulnerable to fragility fractures and COVID-19. The purpose of this study is to analyze the services provided to Medicare beneficiaries both before and during the COVID-19 pandemic to determine how procedure volume was affected in this patient population.

METHODS: We retrospectively analyzed services using the physician or supplier procedure summary data from the Centers for Medicare and Medicaid Services. All services provided by physicians between January 1, 2019, and December 31, 2020, were included. The data were stratified by US census region using insurance carrier number and pricing locality codes. We also compared data between states that maintained governors affiliated with the Democratic or Republican parties for the duration of the study.

RESULTS: There was an overall decrease in claims regarding DRFs management from 2019 to 2020. There was a dramatic decline in procedure volume (-6.3% vs -12.9%). Of all distal radius related claims there was a relative increase in the proportion of operatively managed DRFs in 2020, from 50.2% to 52.0%. The Midwest saw the greatest decline in operatively managed DRFs, whereas the West experienced the smallest per-capita decline across all procedures. After separating the data by party affiliation, it was also found that operative and nonsurgical procedure volumes fell more sharply in states with Democratic governors.

CONCLUSIONS: This study shows a decrease in DRF procedural volume among Medicare beneficiaries. This data suggests that the operative and nonsurgical management of DRFs may have been affected by pandemic factors such as quarantine guidelines and supply chain or resource limitations. This may assist surgeons and health care systems in predicting how similar crises may affect operative volume.

TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

A previously healthy man in his late 20s was diagnosed with a primary undifferentiated non- metastatic tumor of the left arm. After a biopsy, a clear pathological diagnosis could not be established. The tumor had positive immunohistological markers for both an extragonadal germ cell tumor and a high-grade sarcoma. Given the presumed germ cell etiology, he was started on empiric chemotherapy with etoposide and cisplatin. After a few cycles, the tumor showed dramatic response. However, due to poor patient follow- up, it progressed to massive size with severe compromise of the joint and critical neurovascular structures, which led to the decision for limb amputation. Post-surgical checkups showed no recurrence of the primary tumor or metastasis. This is the first report in the literature showing a tumor with these histological characteristics that responded to platinum-based therapy. It provides evidence for the need of more specific markers for the pathological evaluation of undifferentiated neoplasms.

BACKGROUND: Femoral shaft fractures are common in Malawi, with an annual incidence of 44 per 100,000 people. Inadequate treatment and delayed presentation often result in functional, biopsychosocial, and financial challenges for patients. The purpose of this study was to examine the socioeconomic consequences of femoral shaft fractures for patients in Malawi.

METHODS: This study of 42 patients was part of a larger study that prospectively examined quality of life. Questionnaires were distributed to patients at 1-year follow-up following femoral shaft fracture treatment. Patients reported pre- and post-injury standard of living and financial well-being.

RESULTS: Patients reported relatively high transportation costs to and from the hospital. One year after injury, 17 patients (40%) had not returned to work. Of the 25 (60%) who had returned, 5 (20%) changed jobs due to their injury, all reported decreased productivity. Household income decreased for 29% of patients. 20 (49%) of 41 patients reported food insecurity in the week prior to questionnaire completion. Many patients reported changing their residence, borrowing money, selling personal property, and unenrolling children from school due to financial hardship caused by their injury.

CONCLUSION: While the Malawian public healthcare system is free at the point of care, it lacks the financial risk protection that is essential to universal health coverage (UHC). In this study, we found that the indirect costs of care due to femoral shaft fractures had substantial socioeconomic consequences on the majority of patients and their families. Increased investment of financial and human capital should be made into capacity building and preventative measures to decrease the burden of injury, increase access to care, improve care delivery, and provide financial risk protection for patients with traumatic injuries in Malawi.

PURPOSE: The purpose of this study was to develop and validate a finite element (FE) model of the patellofemoral (PF) joint to characterize patellofemoral instability, and to highlight the effect of lateral retinacular release in combination with tibial tuberosity transfer with respect to contact pressures (CP), contact area (CA), and kinematics during knee flexion.

METHODS: A comprehensive, dynamic FE model of the knee joint was developed and validated through parametric comparison of PF kinematics, CP, and CA between FE simulations and in vitro, cadaveric experiments. Using this FE model, we characterized the effect of patellar instability, lateral retinacular release (LR), and tibial tuberosity transfer (TTT) in the setting of medial patellofemoral ligament injury during knee flexion.

RESULTS: There was a high level of agreement in CP, CA, lateral patellar displacement, anterior patellar displacement, and superior patellar displacement between the FE model and the in vitro data (P values 0.19, 0.16, 0.81, 0.10, and 0.36, respectively). Instability conditions demonstrated the greatest CP compared to all of the other conditions. During all degrees of flexion, TTT and concomitant lateral release (TTT + LR) decreased CP significantly. TTT alone shows a consistently lower CA compared to nonrelease conditions with subsequent lateral release further decreasing CA.

CONCLUSIONS: The results of this study demonstrate that the FE model described reliably simulates PF kinematics and CP within 1 SD in uncomplicated cadaveric specimens. The FE model is able to show that tibial tubercle transfer in combination with lateral retinacular release markedly decreases patellofemoral CP and CA and increases lateral patellar displacement that may decrease bony stabilization of the patella within the trochlear groove and promote lateral patellar instability.

CLINICAL RELEVANCE: The goal of surgical correction for patellar instability focuses on reestablishing normal PF kinematics. By developing an FE model that can demonstrate patient PF kinematics and the results of different surgical approaches, surgeons may tailor their treatment to the best possible outcome. Of the surgical approaches that have been described, the biomechanical effects of the combination of TTT with lateral retinacular release have not been studied. Thus, the FE analysis will help shed light on the effect of the combination of TTT with lateral retinacular release on PF kinematics.

PURPOSE: For fractures requiring operative fixation, the "tripod technique" using headless compression screws has recently been described as a less invasive alternative to open reduction and internal fixation with plate and screws. The purpose of this study was to evaluate the clinical and radiographic outcomes of the tripod technique for the treatment of radial head and neck fractures.

METHODS: We performed a retrospective chart review of all radial head and neck fractures treated with the tripod technique at our institution over a 10-year period. Patients with less than 6 months of follow-up were excluded. Outcomes were evaluated at the latest follow-up using range of motion measurements and the Quick Disabilities of the Arm, Shoulder and Hand questionnaire.

RESULTS: We evaluated 13 patients with a mean age of 48 years and average follow-up of 72 months (range, 21-153 months). All the patients achieved union by 12 weeks after surgery. The average postoperative Quick Disabilities of the Arm, Shoulder and Hand score was 5.9 (range, 0-23). The mean flexion was 139°, and the mean extension was -8°. There were no major postoperative complications. Five patients had minor complications. No patients required a reoperation.

CONCLUSIONS: The tripod technique is a useful alternative to the traditional method of plate and screw fixation for unstable radial head and neck fractures.

TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

BACKGROUND: The objective of our study was to compare patient-reported outcome measures, range of motion (ROM), complication rates, and reoperation rates after reverse total shoulder arthroplasty (rTSA) for proximal humeral fractures between patients treated acutely (≤30 days after injury), those treated after initial nonoperative treatment (>30 days after injury), and those treated after failed open reduction-internal fixation. Secondarily, we aimed to identify any patient-, injury-, or surgery-related factors independently associated with our response variables.

METHODS: We identified 576 patients who sustained a proximal humeral fracture treated with primary or revision shoulder arthroplasty between January 2003 and August 2018. The final cohort included 153 patients. Multivariable analysis was used to assess whether explanatory variables were associated with our response variables.

RESULTS: Initial nonoperative treatment compared with acute rTSA was associated with worse Shoulder Subjective Value (P = .04), Shoulder Pain and Disability Index score (P = .03), and Shoulder Pain and Disability Index disability subscale score (P = .03). Only depression was independently associated with worse visual analog scale pain score (P = .04). There was no significant difference in postoperative ROM between the initial treatment groups. Older age was associated with decreased ROM in all planes. Additionally, ipsilateral upper-extremity injury was associated with decreased active abduction (P = .03), and cemented humeral stems were associated with decreased passive abduction (P = .03). Initial nonoperative treatment was associated with increased complication rates (odds ratio, 3.65; 95% confidence interval, 1.11-12.01), and male sex was associated with higher rates of reoperation (odds ratio, 3.53; 95% confidence interval, 1.31-9.51).

CONCLUSIONS: Patients who undergo initial periods of nonoperative management have worse functional outcomes and higher complication rates than those who undergo acute rTSA for proximal humeral fractures. Patients who undergo rTSA after failed open reduction-internal fixation show no difference in patient-reported outcomes compared with those who undergo acute rTSA. In addition, male patients are at higher risk of reoperation, whereas older patients are at risk of decreased ROM. Patients with preoperative depression are at risk of increased pain at 2 years after surgery.