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1.
Foot Ankle Spec ; : 19386400241241097, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38567536

ABSTRACT

BACKGROUND: Lisfranc injuries refer to a disruption or displacement of the tarsometatarsal joint of the foot. Subtle Lisfranc injuries can go undiagnosed on conventional imaging leading to devastating consequences and poor functional outcomes for elite athletes. Objective. The objective of this case study is to present a novel imaging technique using weight-bearing computed tomography (CT) with enhanced stress to identify subtle, dynamically unstable Lisfranc injuries. We illustrate this with a case presentation of an elite athlete who ultimately required surgical fixation for a subtle Lisfranc injury. MATERIALS AND METHODS: To perform an augmented stress weight-bearing CT, the patient was positioned standing, with their feet facing forward, and weight equally distributed. The patient was then coached to symmetrically raise both heels from the scanner platform. This plantarflexion provided augmented stress on the midfoot, allowing for more sensitive imaging of the Lisfranc injury. The weight-bearing CT and augmented stress images undergo 3D reconstruction and postprocessing to render coronal and sagittal images, allowing for comparison of the standard weight-bearing and augmented stress images. RESULTS: We present the case of a 22-year-old collegiate football lineman sustaining a Lisfranc injury. The injury diagnosis was made by magnetic resonance imaging (MRI) and clinical examination, without evidence of injury on weight-bearing XR or standard weight-bearing CT. With augmented stress CT imaging, the Lisfranc instability was noted, leading to surgical fixation, and return to sport the next season. CONCLUSION: We propose this technique for diagnosing subtle, unstable Lisfranc injuries where clinical suspicion persists despite inconclusive imaging, particularly in elite athletes. Further research is needed with larger sample sizes to investigate the sensitivity of this novel imaging technique for the detection of Lisfranc injury. LEVELS OF EVIDENCE: Level 4: Case Report.

2.
Sensors (Basel) ; 24(8)2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38676213

ABSTRACT

The Stingray sensor system is a 15-camera optical array dedicated to the nightly astrometric and photometric survey of the geosynchronous Earth orbit (GEO) belt visible above Tucson, Arizona. The primary scientific goal is to characterize GEO and near-GEO satellites based on their observable properties. This system is completely autonomous in both data acquisition and processing, with human oversight reserved for data quality assurance and system maintenance. The 15 ZWO ASI1600MM Pro cameras are mated to Sigma 135 mm f/1.8 lenses and are controlled simultaneously by four separate computers. Each camera is fixed in position and observes a 7.6-by-5.8-degree portion of the GEO belt, for a total of a 114-by-5.8-degree field of regard. The GAIA DR2 star catalog is used for image astrometric plate solution and photometric calibration to GAIA G magnitudes. There are approximately 200 near-GEO satellites on any given night that fall within the Stingray field of regard, and all those with a GAIA G magnitude brighter than approximately 15.5 are measured by the automated data reduction pipeline. Results from an initial one-month survey show an aggregate photometric uncertainty of 0.062 ± 0.008 magnitudes and astrometric accuracy consistent with theoretical sub-pixel centroid limits. Provided in this work is a discussion of the design and function of the system, along with verification of the initial survey results.

3.
Biocell ; 47(10): 2125-2132, 2023.
Article in English | MEDLINE | ID: mdl-37974562

ABSTRACT

Osteoarthritis (OA), the most common form of joint disease, is characterized clinically by joint pain, stiffness, and deformity. OA is now considered a whole joint disease; however, the breakdown of the articular cartilage remains the major hallmark of the disease. Current treatments targeting OA symptoms have a limited impact on impeding or reversing the OA progression. Understanding the molecular and cellular mechanisms underlying OA development is a critical barrier to progress in OA therapy. Recent studies by the current authors' group and others have revealed that the nuclear factor of activated T cell 1 (NFAT1), a member of the NFAT family of transcription factors, regulates the expression of many anabolic and catabolic genes in articular chondrocytes of adult mice. Mice lacking NFAT1 exhibit normal skeletal development but display OA in both appendicular and spinal facet joints as adults. This review mainly focuses on the recent advances in the regulatory role of NFAT1 transcription factor in the activities of articular chondrocytes and its implication in the pathogenesis of OA.

4.
Nature ; 623(7989): 938-941, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37783227

ABSTRACT

Large constellations of bright artificial satellites in low Earth orbit pose significant challenges to ground-based astronomy1. Current orbiting constellation satellites have brightnesses between apparent magnitudes 4 and 6, whereas in the near-infrared Ks band, they can reach magnitude 2 (ref. 2). Satellite operators, astronomers and other users of the night sky are working on brightness mitigation strategies3,4. Radio emissions induce further potential risk to ground-based radio telescopes that also need to be evaluated. Here we report the outcome of an international optical observation campaign of a prototype constellation satellite, AST SpaceMobile's BlueWalker 3. BlueWalker 3 features a 64.3 m2 phased-array antenna as well as a launch vehicle adaptor (LVA)5. The peak brightness of the satellite reached an apparent magnitude of 0.4. This made the new satellite one of the brightest objects in the night sky. Additionally, the LVA reached an apparent V-band magnitude of 5.5, four times brighter than the current International Astronomical Union recommendation of magnitude 7 (refs. 3,6); it jettisoned on 10 November 2022 (Universal Time), and its orbital ephemeris was not publicly released until 4 days later. The expected build-out of constellations with hundreds of thousands of new bright objects1 will make active satellite tracking and avoidance strategies a necessity for ground-based telescopes.

5.
Ann Med Surg (Lond) ; 85(4): 820-823, 2023 Apr.
Article in English | MEDLINE | ID: mdl-37113843

ABSTRACT

The objective was to determine the most common topic of patient phone calls received by on-call orthopedic residents at a single academic institution in order to identify areas of improvement for patient outcome and resident workload and wellbeing. Design: Patient phone calls over 82 shifts were documented from May 2020 to January 2021 by on-call orthopedic residents. The length, nature, and associated attending physician of each call were recorded, as well as whether the call resulted in an emergency department visit. The nature of each phone call was categorized into one of 12 categories. Setting: An urban, tertiary care academic institution in the Midwest, USA. Participants: All orthopedic residents on-call during this period logged the phone calls that they received and related relevant data. Results: Orthopedic surgery residents took an average of 8.6 patient phone calls (average 53.3 total minutes) per shift. The most common reasons for the phone calls were pain, prescription, and pharmacy concerns, which together represented over half of the calls. Twenty-one (4.1%) phone calls resulted in an emergency department visit. Conclusion: Concerns about pain and prescriptions were among the most common reasons for patient phone calls. This information points to opportunities for interventions that could help guide how postoperative pain is discussed with patients, including providing patients with reasonable expectations for pain control, function, and tools for better self-efficacy. This approach could not only enhance patient care but also decrease resident on-call workload and improve resident wellbeing.

6.
Am J Sports Med ; 51(10): 2748-2757, 2023 08.
Article in English | MEDLINE | ID: mdl-36917833

ABSTRACT

BACKGROUND: "Failure" is a term that is frequently used to describe an unfavorable outcome for patients who undergo surgical treatment for lateral ankle instability (LAI). A standard definition of failure for the surgical treatment of ankle instability has not been established by clinicians and researchers. PURPOSE: To identify the definitions of ankle instability treatment failure that are currently in the literature and to work toward the standardization of the definition. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: A systematic search of MEDLINE, SPORTDiscus, CINAHL, Embase, and Web of Science was conducted to identify clinical studies that included patients who underwent surgical treatment for LAI and included information about surgical failure. Studies with level of evidence 1 to 4 were included in this review. Animal studies, biomechanical studies, cadaveric studies, review articles, and expert opinions were excluded. The included studies were then reviewed for definitions of failure of any surgical procedure that was performed to correct LAI. RESULTS: Of the 1200 studies found, 3.5% (42/1200) published between 1984 and 2021 met the inclusion criteria and were analyzed. After reviewing the data, we found numerous definitions were reported in the literature for LAI surgical failure. The most common was recurrent instability (40% [17/42]), followed by rerupture (19% [8/42]). For the original surgical procedure, the anatomic Broström-Gould technique was used most frequently (57% [24/42]). The failure rate of the Broström-Gould technique ranged from 1.1% to 45.2% depending on the definition of failure. CONCLUSION: There were multiple definitions of failure for the surgical treatment of LAI, which is one of the reasons why the rate of failure can vary greatly. The literature would benefit greatly from the standardization of the definition of ankle instability treatment failure. This definition should include specific, objective physical examination findings that eliminate the ambiguity surrounding failure.


Subject(s)
Joint Instability , Lateral Ligament, Ankle , Orthopedic Procedures , Humans , Ankle Joint/surgery , Lateral Ligament, Ankle/surgery , Ankle/surgery , Orthopedic Procedures/methods , Joint Instability/diagnosis , Joint Instability/surgery , Joint Instability/etiology
7.
Skeletal Radiol ; 52(6): 1221-1227, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36376759

ABSTRACT

OBJECTIVE: We aim to present a novel imaging technique utilizing weight-bearing CT with syndesmotic stress to identify subtle, unstable syndesmotic injuries. We illustrate this with a case presentation of such an injury in an elite athlete that ultimately required operative fixation. MATERIALS AND METHODS: In order to perform an augmented stress weightbearing CT, the patient is in the standing position, feet facing forward, and with weight distributed equally. The patient is then coached to internally rotate the shin and knee. This places an external rotational moment on the TFS due to the planted foot and ankle. The augmented stress images undergo 3D reconstruction and post-processing to render coronal and sagittal images. These are subsequently compared to standard, conventional weightbearing CT images performed without the external rotation stress. RESULTS: We illustrate this technique by presenting a case in which a 21-year-old collegiate athlete sustained a Grade II syndesmotic injury, diagnosed by MRI and clinical exam without evidence of instability by standard weightbearing CT or weightbearing radiographs. After undergoing the augmented stress weightbearing CT, the instability was noted. This prompted subsequent operative fixation and ultimately return to sport. CONCLUSION: We propose this technique for diagnosing unrecognized, subtle dynamically unstable syndesmosis injuries where clinical suspicion persists despite negative imaging, particularly in the elite athlete.


Subject(s)
Ankle Injuries , Joint Instability , Humans , Young Adult , Adult , Ankle Joint , Ankle Injuries/surgery , Weight-Bearing , Tomography, X-Ray Computed , Athletes
8.
J Pediatr Orthop ; 42(3): 158-161, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-35138298

ABSTRACT

INTRODUCTION: Premature radial physeal closure is a relatively rare occurrence in children. When isolated growth arrest of the radius with continued ulnar growth occurs, the resulting ulnar positive deformity leads to altered wrist mechanics and pain. Timely epiphysiodesis of the distal ulna with and without ulnar shortening osteotomy can address these issues, but continued ulnar overgrowth is a possible complication. We seek to evaluate the success rate of the primary epiphysiodesis of the ulna and associated clinical outcomes. METHODS: A chart review was conducted at 2 children's hospitals from 2008 to 2019. Patients between the ages of 6 and 18 years old, with premature distal radius physeal closure, with or without positive ulnar variance, and >2 months follow-up were included. We evaluated the following characteristics for each patient: demographics, initial cause of premature radial physeal closure, ulnar variance, additional procedures performed during epiphysiodesis, preoperative and postoperative pain, range of motion, instability. Summary statistics were conducted and expressed as proportions, medians and means. A paired t test evaluated change in ulnar variance for those who had an ulnar shortening osteotomy performed. RESULTS: Thirty-one wrists among 30 patients were identified, and the median age at the time of surgery was 12.2 years (interquartile range: 3.4). Ulnar shortening osteotomies were performed in 53.1% of cases and distal radius osteotomy in 15.6%. Bone graft was utilized in 25.8% of the epiphysiodesis procedures. There were 2 failures of primary epiphysiodesis indicating an index success rate of 93.7%. The average ulnar variance correction was 3.1 mm (95% confidence interval: 1.9, 4.4). The mean physeal time to closure was 134 days. Preoperative symptoms were resolved for 90.6% cases at final follow-up. CONCLUSION: Ulnar epiphysiodesis successfully terminates ulnar physeal growth in 93.7% of cases. Preoperative symptoms were completely resolved with a median physeal closure of just over 4 months. Ulnar variance was corrected on average by 4.1 mm when a radial or ulnar shortening osteotomy was performed at the time of epiphysiodesis. LEVEL OF EVIDENCE: Level IV-case series.


Subject(s)
Radius Fractures , Ulna , Child , Humans , Infant , Radius/diagnostic imaging , Radius/surgery , Range of Motion, Articular , Ulna/diagnostic imaging , Ulna/surgery , Wrist Joint
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