Publications by Year: 2023

There is rapidly growing interest in minimally invasive surgery (MIS) of the foot and ankle. Technological advances, specifically with the advent of low-speed high-torque burrs, have enabled the expansion of MIS techniques. Accordingly, there is growing literature reporting excellent outcomes of MIS surgery to address many different pathologies of the foot and ankle. MIS techniques are particularly useful for conducting percutaneous osteotomies and bony débridement. These can be used to address bunion deformity, hammertoes, metatarsalgia, bunionette deformity, bone spurs, and hindfoot deformity. A detailed understanding of the technology, equipment, and techniques is crucial to safely conduct MIS of the foot and ankle. When done safely, MIS provides favorable outcomes with an expedited recovery and limited complications.

BACKGROUND: Clinical guidelines recommend low-molecular-weight heparin for thromboprophylaxis in patients with fractures, but trials of its effectiveness as compared with aspirin are lacking.

METHODS: In this pragmatic, multicenter, randomized, noninferiority trial, we enrolled patients 18 years of age or older who had a fracture of an extremity (anywhere from hip to midfoot or shoulder to wrist) that had been treated operatively or who had any pelvic or acetabular fracture. Patients were randomly assigned to receive low-molecular-weight heparin (enoxaparin) at a dose of 30 mg twice daily or aspirin at a dose of 81 mg twice daily while they were in the hospital. After hospital discharge, the patients continued to receive thromboprophylaxis according to the clinical protocols of each hospital. The primary outcome was death from any cause at 90 days. Secondary outcomes were nonfatal pulmonary embolism, deep-vein thrombosis, and bleeding complications.

RESULTS: A total of 12,211 patients were randomly assigned to receive aspirin (6101 patients) or low-molecular-weight heparin (6110 patients). Patients had a mean (±SD) age of 44.6±17.8 years, 0.7% had a history of venous thromboembolism, and 2.5% had a history of cancer. Patients received a mean of 8.8±10.6 in-hospital thromboprophylaxis doses and were prescribed a median 21-day supply of thromboprophylaxis at discharge. Death occurred in 47 patients (0.78%) in the aspirin group and in 45 patients (0.73%) in the low-molecular-weight-heparin group (difference, 0.05 percentage points; 96.2% confidence interval, -0.27 to 0.38; P<0.001 for a noninferiority margin of 0.75 percentage points). Deep-vein thrombosis occurred in 2.51% of patients in the aspirin group and 1.71% in the low-molecular-weight-heparin group (difference, 0.80 percentage points; 95% CI, 0.28 to 1.31). The incidence of pulmonary embolism (1.49% in each group), bleeding complications, and other serious adverse events were similar in the two groups.

CONCLUSIONS: In patients with extremity fractures that had been treated operatively or with any pelvic or acetabular fracture, thromboprophylaxis with aspirin was noninferior to low-molecular-weight heparin in preventing death and was associated with low incidences of deep-vein thrombosis and pulmonary embolism and low 90-day mortality. (Funded by the Patient-Centered Outcomes Research Institute; PREVENT CLOT ClinicalTrials.gov number, NCT02984384.).

Continuum mechanics-based finite element models of the shoulder aim to quantify the mechanical environment of the joint to aid in clinical decision-making for rotator cuff injury and disease. These models allow for the evaluation of the internal loading of the shoulder, which cannot be measured in-vivo. This study uses human cadaveric rotator cuff samples with surface tendon strain estimates, to validate a heterogeneous finite element model of the supraspinatus-infraspinatus complex during various load configurations. The computational model was considered validated when the absolute difference in average maximum principal strain for the articular and bursal sides for each load condition estimated by the model was no greater than 3% compared to that measured in the biomechanical study. The model can predict the strains for varying infraspinatus loads allowing for the study of load sharing between these two tightly coordinated tendons. The future goal is to use the modularity of this validated model to study the initiation and propagation of rotator cuff tear and other rotator cuff pathologies to ultimately improve care for rotator cuff tear patients.

INTRODUCTION: Iliopsoas hematoma with femoral nerve palsy is a rare phenomenon with no consensus treatment algorithm. The objective of this study was to perform a systematic review of all reported cases of femoral nerve palsy secondary to iliopsoas hematoma to better elucidate it's optimal treatment.

MATERIALS AND METHODS: Queries of the PubMed, Embase, and Cochrane databases were performed for reports available in English of femoral nerve palsy secondary to iliopsoas, psoas, or iliacus hematoma. 1491 articles were identified. After removal of duplicated publications and review of abstract titles via a majority reviewer consensus, 217 articles remained for consideration. Dedicated review of the remaining articles (including their reference sections) yielded 122 articles representing 174 distinct cases. Clinical data including patient age, sex, medical history, use of pharmacologic anticoagulation, sensory and motor examination at presentation and follow-up, hematoma etiology and location, time to intervention, and type of intervention were collected. Descriptive statistics were generated for each variable.

RESULTS: Femoral nerve palsy secondary to iliopsoas hematoma occurred at a mean age of 44.5 years old. A majority of patients (60%) were male, and a majority of hematomas (54%) occurred due to pharmacologic anticoagulation. Most hematomas (57%) were treated conservatively, and almost half (49%) - regardless of treatment modality - resulted in persistent motor deficits at final follow-up. A minority of patients treated surgically (34%) had residual motor deficit at final follow-up, while 66% of those treated medically had resultant motor deficits, although no direct statistical comparison was able to be performed.

DISCUSSION AND CONCLUSIONS: The disparate available data on iliopsoas hematoma with femoral nerve palsy precludes the completion of a true metanalysis, and therefore any conclusions on an optimal treatment algorithm. Based on review of the literature, small to moderate hematomas are often treated conservatively, while larger hematomas with progressive neurological symptoms are usually managed with a percutaneous decompression or surgery.

LEVEL OF EVIDENCE: IV.

5T4 (trophoblast glycoprotein encoded by TPBG ) is a cancer/testis antigen highly expressed in renal cell carcinoma (RCC) and many other cancers but rarely in normal tissues. Interest in developing 5T4 as a prognostic biomarker and direct targeting of 5T4 by emerging receptor-engineered cellular immunotherapies has been hampered by the lack of validated 5T4-specific reagents for immunohistochemistry (IHC). We tested 4 commercially available monoclonal antibodies (mAbs) for the detection of 5T4 in formalin-fixed, paraffin-embedded RCC and normal tissues. Using parental and TPBG -edited A498 cells, 3 mAbs showed 5T4 specificity. Further analyses focused on 2 mAbs with the most robust staining (MBS1750093, Ab134162). IHC on tissue microarrays incorporating 263 renal tumors showed high staining concordance of these 2 mAbs ranging from 0.80 in chromophobe RCC to 0.89 in advanced clear cell RCC (ccRCC). MBS1750093, the most sensitive, exhibited 2+/3+ staining in papillary RCC (92.2%) > advanced ccRCC (60.0%) > chromophobe RCC (43.6%) > localized ccRCC (39.6%) > oncocytoma (22.7%). RNA in situ hybridization also revealed high levels of TPBG RNA were present most frequently in papillary and advanced ccRCC. In advanced ccRCC, there was a trend towards higher 5T4 expression and regional or distant metastases. Normal organ controls showed no or weak staining with the exception of focal moderate staining in kidney glomeruli and distal tubules by IHC. These data identify mAbs suitable for detecting 5T4 in formalin-fixed, paraffin-embedded tissues and demonstrate both interpatient and histologic subtype heterogeneity. Our validated 5T4 IHC protocol will facilitate biomarker studies and support the therapeutic targeting of 5T4.

BACKGROUND: Meniscal and chondral damage is common in the patient undergoing revision anterior cruciate ligament (ACL) reconstruction.

PURPOSE: To determine if meniscal and/or articular cartilage pathology at the time of revision ACL surgery significantly influences a patient's outcome at 6-year follow-up.

STUDY DESIGN: Cohort study; Level of evidence, 3.

METHODS: Patients undergoing revision ACL reconstruction were prospectively enrolled between 2006 and 2011. Data collection included baseline demographics, surgical technique, pathology, treatment, and scores from 4 validated patient-reported outcome instruments: International Knee Documentation Committee (IKDC), Knee injury and Osteoarthritis Outcome Score (KOOS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Marx Activity Rating Scale. Patients were followed up at 6 years and asked to complete the identical set of outcome instruments. Regression analysis assessed the meniscal and articular cartilage pathology risk factors for clinical outcomes 6 years after revision ACL reconstruction.

RESULTS: An overall 1234 patients were enrolled (716 males, 58%; median age, 26 years). Surgeons reported the pathology at the time of revision surgery in the medial meniscus (45%), lateral meniscus (36%), medial femoral condyle (43%), lateral femoral condyle (29%), medial tibial plateau (11%), lateral tibial plateau (17%), patella (30%), and trochlea (21%). Six-year follow-up was obtained on 79% of the sample (980/1234). Meniscal pathology and articular cartilage pathology (medial femoral condyle, lateral femoral condyle, lateral tibial plateau, trochlea, and patella) were significant drivers of poorer patient-reported outcomes at 6 years (IKDC, KOOS, WOMAC, and Marx). The most consistent factors driving outcomes were having a medial meniscal excision (either before or at the time of revision surgery) and patellofemoral articular cartilage pathology. Six-year Marx activity levels were negatively affected by having either a repair/excision of the medial meniscus (odds ratio range, 1.45-1.72; P≤ .04) or grade 3-4 patellar chondrosis (odds ratio, 1.72; P = .04). Meniscal pathology occurring before the index revision surgery negatively affected scores on all KOOS subscales except for sports/recreation (P < .05). Articular cartilage pathology significantly impaired all KOOS subscale scores (P < .05). Lower baseline outcome scores, higher body mass index, being a smoker, and incurring subsequent surgery all significantly increased the odds of reporting poorer clinical outcomes at 6 years.

CONCLUSION: Meniscal and chondral pathology at the time of revision ACL reconstruction has continued significant detrimental effects on patient-reported outcomes at 6 years after revision surgery.

UNLABELLED: International observerships are one of many efforts aimed at addressing disparities in orthopaedic trauma care globally. However, their impact on visiting surgeons and their home countries, as well as the challenges faced by participating surgeons, are not well-documented.

METHODS: A survey was distributed to overseas surgeons who participated in an orthopaedic trauma observership from 2009 to 2020. Surgeons were identified through North American institutions previously recognized by the authors as having hosted international observerships. Information gathered included participant demographics, details of and perceived impact of the observership, and barriers faced before, during, and after the program. Responses from 148 international surgeons (ISs) from 49 countries were analyzed.

RESULTS: Sixty percent of observerships were at academic programs, 57% lasted 1-3 months, and 60% were self-funded. Participants identified cost and housing as primary barriers. After completing their observership, lack of funding, equipment and support staff, and excessive workload prevented participants from implementing changes at their clinical practice. Most observers believed that they gained relevant clinical (89%) and surgical knowledge (67%) and developed a professional network of North American hosts (63%). The most common suggested changes to the observership were greater hands-on experience in the operating room and structured goal setting relevant to the visiting surgeon.

CONCLUSIONS: Visiting surgeons find North American orthopaedic trauma observerships helpful in improving their surgical and clinical skills. However, financial constraints and resource limitations at their clinical practice and limited operative experience during the observership present barriers to maximizing this clinical experience. To enhance the relevance of clinical observerships for ISs and impact global orthopaedic trauma care, the unique needs and challenges facing ISs must be addressed.

LEVEL OF EVIDENCE: IV-Cross-Sectional Study.

BACKGROUND: Biologic healing after rotator cuff repair remains a significant challenge. Injectable biologic augmentation may improve tissue quality at the suture-tendon interface.

PURPOSE: To investigate the effect of injectable biologic supplementation in rotator cuff repair and to assess the quality and adherence to evolving reporting standards.

STUDY DESIGN: Systematic review; Level of evidence, 3.

METHODS: A systematic review was conducted following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Included were 40 studies: 29 preclinical (in vivo animal models) and 11 clinical. Each clinical study was assessed for quality, risk of bias, and adherence to relevant MIBO (Minimum Information for Studies Evaluating Biologics in Orthopaedics) guidelines. The outcomes of interest were reported load to failure, load to gap, gap size, and stiffness in the preclinical studies, and healing rate and any patient-reported outcome measures in the clinical studies.

RESULTS: Injectables reported included growth factors (eg, transforming growth factor-beta 3, erythropoietin), bone marrow-derived mesenchymal stem cells and adipose-derived mesenchymal stem cells (ADSCs), and other agents such as platelet-rich plasma (PRP) and hyaluronic acid. The most common findings for preclinical injectables were increased load to failure (16/29 studies; 55.2%) and improved collagen histological quality (11/29 studies; 37.9%). All 11 clinical studies (10 PRP, 1 ADSC) indicated no adverse events, with similar or improved patient-reported outcomes compared with repairs in the control groups. In 1 study utilizing an innovative delivery technique, a concentrated PRP globule with fibrin matrix was shuttled over a suture to maintain concentrated PRP at the repair site and demonstrated a significant decrease in retears (P = .03) at a 31-month follow-up. A matched-cohort study investigating augmentation with ADSCs demonstrated a significantly lower retear rate in the ADSC-augmented group than the control group at a 28-month follow-up (P < .001). On average, the clinical studies adhered to 66% of relevant MIBO reporting guidelines and had a low risk of bias.

CONCLUSION: Approximately 83% of preclinical studies found a positive biomechanical or histological effect, with no studies showing an overall negative effect. Clinically, utilization of innovative delivery techniques may reduce the risk of arthroscopic washout of PRP and improve retear rates. ADSCs were shown to reduce retear rates at a 28-month follow-up.

BACKGROUND: Insurance status is important as medical expenses may decrease the likelihood of follow-up after musculoskeletal trauma, especially for low-income populations. However, it is unknown what insurance factors are associated with follow-up care. In this study, we assessed the association between insurance plan benefits, the end of the post-surgical global period, and follow-up after musculoskeletal injury.

METHODS: This is a retrospective cohort study of 394 patients with isolated extremity fractures who were treated at three level-I trauma centers over four months in 2018. Paired t-tests were utilized to assess the likelihood of follow-up in relation to the 90-day post-surgical global period. Regression analysis was used to assess factors associated with the likelihood of follow-up. Supervised machine learning algorithms were used to develop predictive models of follow-up after the post-surgical global period.

RESULTS: Our final analysis included 328 patients. Likelihood of follow-up did not significantly change while within the post-surgical global period. When comparing follow-up within and outside of the post-surgical global period, there was a 20.1% decrease in follow-up between the 6-weeks and 6-month time points (68.3% versus 48.2%, respectively; p < 0.0001). Medicaid insurance compared to Medicare (OR 0.27, 95% confidence interval (CI) = [0.09, 0.84], p = 0.02) was a predictor of decreased likelihood of follow-up at 6-months post-operatively.

CONCLUSIONS: Our study demonstrates a statistically significant decrease in follow-up for orthopaedic trauma patients after the post-surgical global period, particularly for patients with Medicaid or Private insurance.