Ankle, knee, and elbow arthrography: 2022 survey of Society of Skeletal Radiology members.

OBJECTIVE: To determine the preferred ankle, knee, and elbow arthrography injection techniques for Society of Skeletal Radiology (SSR) members and whether more recently described techniques are gaining acceptance. We also sought to determine whether the concept of knowledge translation might explain differences between the preferred technique, year of fellowship graduation, and year the newer technique was described. MATERIALS AND METHODS: A 29-question survey was created in Qualtrics and submitted to current SSR members to determine if they perform knee, elbow, and ankle arthrography, and if so, the year of fellowship completion and preferred approaches. Survey respondents indicated the starting and ending needle tip positions for three knee, two elbow, and three ankle arthrography approaches using grids placed over provided frontal and lateral radiographs. RESULTS: Two hundred seventy-four SSR members (mean post-fellowship 13 years; range 0-38) completed the survey and performed fluoroscopic-guided knee (93%), elbow (95%), and ankle (75%) arthrography. Preferred approaches included the following: knee lateral subpatellar (43%), anterior (40%); elbow radiocapitellar (74%); ankle anterior/peritendon (70%), lateral mortise (24%). Preference of newer technique was related to fellowship graduation year and publication year for the ankle mortise (26% before, 42% after; p = 0.03) and posterior trans-triceps elbow articles (19% before, 33% after; p < 0.01). The anterior knee approach preference increased from 11% in 2008 to 40% (p ≤ 0.001). CONCLUSION: Nearly twice as many SSR members who graduated after the posterior trans-triceps and ankle mortise techniques were published prefer them for performing arthrography, possibly due to knowledge translation. The preference of the anterior knee arthrography approach has increased nearly fourfold since 2008.

Does MRI alter management in patients 60 years and older with chronic knee pain: correlation with radiographs and clinical parameters.

OBJECTIVE: To determine if MRI altered management in patients ≥ 60 years old with chronic knee pain. MATERIALS AND METHODS: Consecutive patients ≥ 60 years old with knee MRI and radiographs within 90 days were included. Exclusion criteria included mass/malignancy, recent trauma, and infection. Standing AP and PA flexion views were evaluated using Kellgren-Lawrence (KL) and International Knee Documentation Committee (IKDC) scales. Pertinent clinical history was recorded. MRIs were considered to alter management if subchondral fracture was identified or subsequent arthroscopy was performed due to an MRI finding. RESULTS: Eighty-five knee MRI/radiograph exams were reviewed; mean 68.2 years (60-88), 47:38 F:M. Twenty knee MRIs (24%) had either a subchondral fracture (n = 9) or meniscal tear (n = 11) prompting arthroscopy. On PA flexion view, 0/20 of these studies had KL grade 4 and 70% (14/20) had KL grade 0-1 compared to the remaining MRIs having 15.4% (10/65) KL grade 4 and 38.5% (25/65) KL grade 0-1 (p = 0.03). A 10-pack-year tobacco history, 38% vs 18%, was associated with a subchondral fracture or arthroscopy (p = 0.06). Subchondral fractures were more prevalent in older patients (mean 72.4 vs 67.7 years; p = 0.03). CONCLUSION: In patients ≥ 60 years old with chronic knee pain, MRI altered management in ~ 24% of cases; 70% in patients with KL grade 0-1, and none in patients with KL grade 4. MRI may benefit older patients with minimal osteoarthritis but not those with end-stage disease. Patients with ≥ 10 pack years of smoking may also benefit from MRI.

Musculoskeletal glomus tumor: a review of 218 lesions in 176 patients.

OBJECTIVE: To review the spectrum of clinical and imaging features of glomus tumor involving the musculoskeletal system including the typically solitary forms as well as the rarer multifocal forms (glomuvenous malformation and glomangiomatosis). MATERIALS AND METHODS: A retrospective review of our institutional pathology database from 1996 to 2023 identified 176 patients with 218 confirmed glomus tumors. Primary imaging studies included MRI (125), radiographs (100), clinical/intraoperative photos (77), and ultrasound (36). Lesions were divided into two groups: those that are typically solitary involving specific anatomic areas (finger, toe, soft tissue, coccyx, and bone), and those that are multifocal (glomuvenous malformation and glomangiomatosis). RESULTS: The finger was the most frequently involved anatomic location for the classic (sporadic) glomus tumor occurring in 51% of patients, 77% of which were women, with the nail plate involved in more of the 75% of cases. Sporadic lesions involving the skin, subcutaneous adipose tissue, and deep soft tissue were termed "soft tissue," and were identified in 39% of patients, 90% of which were in the extremities and in men in 81% of cases. The multifocal syndromic forms of glomus disease occurred in younger individuals and involved less than 6% of the study group. Patients with glomuvenous malformation presented early with predominantly cutaneous involvement, while those with glomangiomatosis present later, often with both superficial and deep involvement, and a high rate of local tumor recurrence. CONCLUSION: While glomus tumor is generally uncommon, it frequently involves the musculoskeletal extremities. Knowledge of the spectrum of characteristic locations and appearances will facilitate definitive diagnosis.

Osteochondral Lesions of the Ankle and Foot.

Osteochondral lesions (OCLs) in the ankle are more common than OCLs of the foot, but both share a similar imaging appearance. Knowledge of the various imaging modalities, as well as available surgical techniques, is important for radiologists. We discuss radiographs, ultrasonography, computed tomography, single-photon emission computed tomography/computed tomography, and magnetic resonance imaging to evaluate OCLs. In addition, various surgical techniques used to treat OCLs-debridement, retrograde drilling, microfracture, micronized cartilage-augmented microfracture, autografts, and allografts-are described with an emphasis on postoperative appearance following these techniques.

Time-Dependent Change in Carpal Tunnel Cross-Sectional Area and Transverse Carpal Ligament Thickness Using Serial Magnetic Resonance Imaging Studies-An Anatomical Study.

PURPOSE: Idiopathic carpal tunnel syndrome (CTS) is a common compressive neuropathy. Aging and female sex are risk factors, but the reasons are unclear. The purpose of this study was to evaluate whether identifiable radiographic changes resulting in a decrease in carpal tunnel area (CTA) over time exist. METHODS: A database search of a multicenter, academic, tertiary institution from 1998 to 2021 identified 433 patients with serial wrist magnetic resonance images (MRI) at least 5 years apart. Fifty-six met the inclusion criteria with adequate films to measure CTA and transverse carpal ligament (TCL) thickness at the same slice location-the carpal tunnel inlet, hook of the hamate, and carpal tunnel outlet-independently by two observers who were blinded to each other's measurements. Rates for the change in CTA and TCL thickness were calculated at all three locations. RESULTS: Thickness of the TCL increased, whereas that of the CTA decreased over time. Inlet CTA decreased by 0.9 mm2 per year (95% CI: 0.34-1.5), outlet CTA decreased by 1.8 mm2 per year (95% CI: 1.2-2.5), and CTA at the hook of the hamate decreased by 1.6 mm2 per year (95% CI: 1.0-2.0 per year). The TCL thickened by 0.02 mm per year at all three sections. Taller patients had a decreased rate of CTA loss. CONCLUSIONS: In this select cohort, TCL thickened and CTA decreased with time. TCL thickening accounted for about half of the variation in CTA, suggesting that this is a possible contributor to this change. Hypertrophy of the carpal tunnel floor may account for the remaining variation in CTA. The question of whether these results are reliable and generalizable to the general population, or a major influence in the pathophysiology of CTS, is unknown. CLINICAL RELEVANCE: Small decreases in CTA and thickening of the TCL occur with aging. Whether this is a contributing factor in the development of CTS requires further study.

Boldness, movement and exploration tendency in round goby (Neogobius melanostomus) in Southern Ontario.

Invasive species have the potential to damage ecosystems outside their native range. At an invasion front, individuals are faced with the unfamiliar conditions of a novel environment. Therefore, certain behavioural traits such as boldness and movement likely play a role in invasion ecology. If behavioural traits of this kind are influenced by differing selection pressures between demographic groups of the same species, this could have broad implications for the management of expanding invasion fronts. To determine whether the invasive round goby (Neogobius melanostomus, Pallas, 1814) exhibits sex- and habitat-based differences in boldness and movement across the invasion front, the authors assessed individual movement and exploration tendency under controlled lab settings using video analysis in a behavioural assay. N. melanostomus from lakes tended to be bolder than those from streams, and females tended to be bolder than males. This study provides evidence for sex- and habitat-based differences in behaviour in this globally invasive species that the authors hope will assist in forming the foundation for contextually appropriate management strategies.

Calcific Tendinosis Reduces Diagnostic Performance of Magnetic Resonance Imaging in the Detection of Rotator Cuff Tears.

OBJECTIVE: This study aimed to investigate the effect of calcific tendinosis on the diagnosis of rotator cuff tears (RCTs) on magnetic resonance imaging (MRI) and magnetic resonance arthrography (MRA). MATERIALS AND METHODS: Calcific tendinosis was confirmed radiographically. Two musculoskeletal radiologists then retrospectively and independently reviewed the MRI/MRA examinations, with surgery or arthroscopy performed within 90 days of the MRI. Rotator cuffs were categorized as no tear, partial-thickness tear, and full-thickness tear. Partial-thickness tear/full-thickness tear groups were combined for analysis. RESULTS: Forty-eight MRI (mean age, 63.4 years; range, 37-83 years; female-to-male ratio, 29:19) and 7 MRA (mean age, 49.2 years; range, 25-60 years; female-to-male ratio, 4:3) patients were included. Reader 1 and reader 2 sensitivity/specificity values for RCTs on MRI were 95%/50% and 89%/30%, and the values on MRA were 100%/67% and 100%/100%, respectively. Overall agreement was present in 87% (48 of 55; κ = 0.55 [95% confidence interval, 0.26-0.85]). CONCLUSIONS: Magnetic resonance imaging has decreased specificity in diagnosing RCTs when calcific tendinosis is present. Magnetic resonance arthrography performed better in this population and could be considered.

Postoperative Ankle Imaging, 2022.

Postoperative ankle imaging requires knowledge of the underlying surgical techniques, the usefulness of various imaging modalities, as well as an appreciation for the desired clinical outcomes. Surgical procedures discussed in this article are tibiotalar fracture fixation, tibiotalar, subtalar, and tibiotalocalcaneal arthrodesis, total ankle arthroplasty, talar osteochondral lesion repair and grafting, lateral ligamentous repair and reconstruction, and peroneal and Achilles tendon repair and reconstruction. Imaging can play a vital role in determining if the expected outcome has been achieved and identifying complications, with particular emphasis placed on the use of radiographs, computed tomography (including weight-bearing), magnetic resonance imaging, and ultrasonography.

Assessing Femoral Trochlear Morphologic Features on Cross-Sectional Imaging Before Trochleoplasty: Dejour Classification Versus Quantitative Measurement.

OBJECTIVE. The purpose of this study is to assess the use of cross-sectional imaging to qualitatively and quantitatively categorize trochlear dysplasia as low grade (type A) or high grade (types B-D) according to the Dejour classification. MATERIALS AND METHODS. A retrospective review of CT and MRI knee examinations performed before patients underwent deepening trochleoplasty was independently conducted by two musculoskeletal radiologists. Each case of trochlear dysplasia was qualitatively assigned a Dejour type. Subsequently, quantitative measurements of the sulcus angle, distance from the tibial tubercle to the trochlear groove, trochlear depth, lateral trochlear inclination, trochlear facet asymmetry, and degree of patellar lateralization were performed. RESULTS. A total of 35 patients (29 female patients and six male patients; mean age, 21.1 years) with 39 affected knees (17 right knees and 22 left knees) were included. Readers had exact qualitative agreement using Dejour classification for 30 of 39 knees (77% [κ = 0.77; 95% CI, 0.62-0.91]) and agreement on classification of low-grade versus high-grade dysplasia for 36 of 39 knees (92%). For these 36 knees, the mean differences in measurements of low- versus high-grade dysplasia, respectively, were as follows: for sulcus angle, 153° versus 168° (p < 0.001); for trochlear depth, 4 versus 1 mm (p < 0.001); for lateral trochlear inclination, 12 versus 7 mm (p < 0.02); and for decreased trochlear facet asymmetry, 13% versus 92% (p < 0.001). Trochlear depth, lateral trochlear inclination, and trochlear facet asymmetry were also different in comparisons of knees with Dejour type B and C trochlear dysplasia versus those with Dejour types B and D (all p < 0.05). No quantitative measurement differentiated between trochlear dysplasia of Dejour types C and D. The distance from the tibial tubercle to the trochlear groove and the degree of patellar lateralization were not statistically different between low- and high-grade dysplasia. CONCLUSION. Qualitative use of the Dejour classification accurately categorizes trochlear dysplasia as low grade or high grade in 92% of cases, with exact agreement reached in 77% of cases. Furthermore, the trochlear depth, lateral trochlear inclination, trochlear facet asymmetry, and sulcus angle can differentiate between low-grade and high-grade dysplasia, with trochlear depth, lateral trochlear inclination, and trochlear facet asymmetry useful for differentiating between Dejour types B and C and Dejour types B and D.

Desmoplastic Fibroblastoma: An Uncommon Tumor With a Relatively Characteristic MRI Appearance.

OBJECTIVE. We undertook this study to determine the radiologic features of desmo-plastic fibroblastoma. MATERIALS AND METHODS. We reviewed available radiologic images for 29 pathologically confirmed desmoplastic fibroblastomas, including images from MRI, radiography, ultrasound (US), and CT. RESULTS. The patient population included 14 women and 15 men (mean age, 60 years; range, 23-96 years). Typically, lesions were oval or lobulated and relatively small (mean, 5.6 cm). In 14 of the 22 cases that included patient histories, lesions had grown slowly, with two eventually causing pain. The remaining eight were discovered incidentally. All lesions involved or were below the deep fascia. Lesions were well-defined and associated with muscle (45%), deep fascia (28%), joint (21%), or tendon (7%). MR images were available in 26 cases; 14 included unenhanced and contrast-enhanced studies. On MRI imaging all lesions were well-defined and adjacent to dense connective tissue. On T1-weighted images, lesions showed varying amounts of low and intermediate signal intensity similar to that of tendon and skeletal muscle, respectively. On fluid-sensitive images, lesions were more heterogeneous, generally showing a wider spectrum of decreased to intermediate signal intensity. On contrast-enhanced MR images, enhancement was characteristically peripheral and septal with patchy areas of homogeneity. In the 10 cases with radiographs, images showed negative findings or a nonmineralized mass. The 10 available ultrasound studies showed mixed echogenicity. In eight patients, unenhanced CT showed lesions having attenuation similar to that of skeletal muscle. CONCLUSION. Desmoplastic fibroblastoma is an uncommon neoplasm with a relatively characteristic MRI appearance.

Highlights of the annual scientific meeting of the Society of Skeletal Radiology (SSR) 2019, Scottsdale, Arizona, USA.

Peer-reviewed abstracts presented at the 2019 Society of Skeletal Radiology (SSR) Annual Meeting were reviewed following oral presentation. Topics felt to be of potential interest to musculoskeletal (MSK) investigators and practicing clinicians are highlighted in this compilation and analysis of the meeting. New concepts regarding MSK imaging and intervention, MSK protocols and techniques, and quality improvement are included. ePoster highlights are also presented.

Iatrogenic humeral anatomic neck fracture after intraosseous vascular access.

Intraosseous infusion has become a key tool in the resuscitation of critically ill or injured patients, both in pre-hospital settings and in emergency departments. Intraosseous access is obtained through the percutaneous placement of a needle into the medullary space of a bone, thereby allowing access into the systemic venous circulation via the medullary space, which is essential to treat patients in shock, cardiac arrest, airway compromise, or major trauma. This becomes critically important when obtaining conventional intravenous access is difficult or impossible. Few cases of iatrogenic fracture have been reported for intraosseous access in the tibia and no case to-date has been reported of iatrogenic fracture secondary to humeral access. We report a case of a 55-year-old patient being resuscitated emergently with proximal humeral intraosseous infusion for cardiac and respiratory arrest secondary to status epilepticus. After successful resuscitation and removal of the intraosseous cannula, the patient noted new-onset shoulder pain. The patient was ultimately diagnosed with an iatrogenic fracture of the anatomic neck of the humerus through the intraosseous needle tract when the appropriate history was obtained in conjunction with cross-sectional imaging. As the use of intraosseous access expands, such fractures may well be seen more frequently. Intraosseous access is limited to the period of resuscitation and the cannula is often not present at the time of imaging. It is important for radiologists to recognize the findings related to intraosseous access as well as this complication with its characteristic locations and morphology.

Calcific Tendonitis of the Shoulder: Protector or Predictor of Cuff Pathology? A Magnetic Resonance Imaging-Based Study.

PURPOSE: The purpose of this investigation is to assess the incidence of rotator cuff tears in cases of calcific tendonitis and evaluate for differences in the incidences of rotator cuff tears by magnetic resonance imaging (MRI) between calcific lesions of different morphology, size, or location. METHODS: This single-center study involved a retrospective chart review searching for patients from January 2010 to April 2017 with a diagnosis of calcific tendonitis of the shoulder based on review of all MRI reads done on patients with shoulder pain. Anteroposterior radiographic and MRI studies were reviewed by a musculoskeletal radiologist to assess calcific tendonitis morphology, size, distance from cuff insertion, and any rotator cuff tear. An additional radiologist evaluated calcific tendonitis size, morphology, and location to evaluate the reliability of these variables. RESULTS: In the final cohort of 318 shoulders with calcific tendonitis, the incidence of concomitant rotator cuff tears was 56%. Of all 177 tears, 164 (93%) were partial-thickness and 13 (7%) were complete. Type III calcification morphology (cloudy with soft contour) was most frequently associated with rotator cuff tears and demonstrated an increased odds of tear by a factor of 1.8 (CI95% 1.1-2.9).There was no statistical difference regarding calcification size or location prognosticating rotator cuff tears or tear thickness. Intraclass correlation coefficients for calcification size, morphology, and location were 0.78, 0.30, and 0.50, respectively. CONCLUSIONS: The incidence of rotator cuff tears in cases of calcific tendonitis in this cohort of patients who underwent MRI is higher than previously reported. Cloudy-appearing calcified lesions showed a significant association with rotator cuff tears with an odds ratio of 1.8. Specific locations or sizes of calcified lesions do not appear to be reliable factors to predict concomitant rotator cuff tears. Interobserver agreement for these radiographic variables ranged from fair to substantial and prompt a cautious interpretation of these results. LEVEL OF EVIDENCE: IV Retrospective Case Series.

Percutaneous image-guided bone biopsy of osteomyelitis in the foot and pelvis has a low impact on guiding antibiotics management: a retrospective analysis of 60 bone biopsies.

OBJECTIVE: Image-guided percutaneous bone biopsy may be requested by clinicians to guide antibiotics management decisions in patients with extremity osteomyelitis. Much of the clinical literature describes a high rate of bone biopsy culture positivity in patients with osteomyelitis, but anecdotally biopsy is felt to be fairly low yield in many musculoskeletal radiology practices. The objective of the study is to determine the culture positivity rate and clinical utility of bone biopsy in guiding the management of patients with osteomyelitis. MATERIALS AND METHODS: All image-guided bone biopsy procedures of the pelvis or foot performed at a single institution were identified by a retrospective report search, and only those with a clinical suspicion for infection were included. Cases were included based on convincing imaging findings of osteomyelitis on retrospective review. Microbiology results were reviewed in the clinical chart, as were antibiotics management decisions and response to antibiotics therapy. RESULTS: A total of 60 bone biopsies met the inclusion criteria, 25 within the foot and 35 biopsies of the pelvis. Overall, 11 out of 60 core biopsies (18%) yielded positive cultures. Antibiotics management was altered in only 27% patients with a positive culture; thus, only 5% of patients with MRI findings of osteomyelitis undergoing biopsy had an impact on management. CONCLUSION: Percutaneous bone biopsies may have a low rate of culture positivity, and even when positive, frequently do not have an impact on antibiotics choice. These data differ from much of the clinical literature, which describes a very high rate of culture positivity.

Spinal blastomycosis: unusual musculoskeletal presentation with literature review.

We report a case of a 41-year-old male who presented to our institution with a large groin mass. CT, MRI and PET imaging was performed and was concerning for a soft tissue abscess likely originating in the lumbar spine. Differential considerations included infection, with atypical infections such as tuberculosis strongly considered. Biopsy revealed fungal elements preliminarily reported as consistent with Cryptococcus neoformans but later revealed to be Blastomyces dermatitidis. The patient responded positively following the introduction of appropriate treatment. This case illustrates the imaging similarities between spinal blastomycosis, spinal tuberculosis, and other fungal infections as well as the need for biopsy to differentiate.

Incidence of gadolinium or fluid signal within surgically proven glenoid labral tears at MR arthrography.

OBJECTIVE: To determine how often patients with surgically proven labral tears have labral signal on shoulder MR arthrography (MRA) that is not equal to gadolinium or fluid on T1- and T2-weighted images, respectively. MATERIALS AND METHODS: Consecutive patients with surgical repair of a SLAP or Bankart labral tear within 95 days of an MRA were included. Using cartilage signal as an internal reference, two musculoskeletal (MSK) radiologists retrospectively categorized labral signal as T1-hyperintense, T1-gadolinium, T2-hyperintense, or T2-fluid. In patients without T1-gadolinium or T2-fluid labral signal, secondary findings such as the orientation, extent, shape, and width of the abnormal signal was recorded. Statistical analyses were performed using Fisher's test and ANOVA. RESULTS: Sixty-one labral tears (36 SLAP and 25 Bankart) in 54 patients (mean age, 30.7; F:M 8:46) met the inclusion criteria. In 67% and 76% of SLAP and Bankart labral tears, T1-gadolinium signal was present (p = 0.43). T2-fluid signal was present in 50% and 92% of these same labral tears (p = 0.001). The absence of T1-gadolinium or T2-fluid signal was more common in SLAP tears (33%) compared to Bankart tears (8%) (p = 0.02). In the SLAP cases, at least two secondary findings of a SLAP tear were present in 92% (11/12). CONCLUSIONS: Lack of surfacing T1-gadolinium or T2-fluid labral signal is unusual in Bankart tears but relatively common in SLAP tears. However, a SLAP tear was diagnosed in 92% of these 12 cases when two secondary findings were present.

What Is the Role of Repeat Aspiration in the Diagnosis of Periprosthetic Hip Infection?

BACKGROUND: The American Academy of Orthopedic Surgeons clinical practice guideline currently recommends repeat joint aspiration when workup of periprosthetic joint infection (PJI) reveals conflicting data. This guideline is based on a single study of 31 patients published 25 years ago. We sought to determine the correlation between first and second aspirations and factors that may play a role in variability between them. METHODS: Sixty patients with less than 90 days between aspirations and no intervening surgery were identified at our institution and classified by Musculoskeletal Infection Society (MSIS) criteria as infected, not infected, or not able to determine after both aspirations. Culture results from both aspirations were recorded. The rates of change and correlation in clinical diagnosis and culture results between aspirations were determined. RESULTS: Repeat aspiration changed the diagnosis in 26 cases (43.3%, 95% confidence interval 31.6-55.9, kappa coefficient 0.32, P < .001), and the culture results in 25 cases (41.7%, 95% confidence interval 30.1-54.3, kappa coefficient 0.27, P < .01). Among patients initially MSIS negative, the proportion who changed to MSIS positive was greater for those with a history of prior PJI compared to those without (66.7% vs 0%, P < .05), and the first aspiration mean volume was higher for those changed to MSIS positive compared to those that remained MSIS negative (12.0 vs 3.0 mL, P < .01). Among patients initially MSIS positive, the proportion of patients who changed to MSIS negative was greater for those with a history of adverse local tissue reaction (ALTR) to metal debris compared to patients without suspicion of ALTR (100% vs 7.7%, P < .05). CONCLUSION: Repeat aspiration is particularly useful in patients with conflicting clinical data and prior history of PJI, suspicion of ALTR, or with high clinical suspicion of infection.

Retrospective analysis of equestrian-related injuries presenting to a level 1 trauma center.

OBJECTIVE: Report the incidence, pattern, and severity of equestrian-related injuries presenting to a rural level 1 trauma center and detail the total radiation dose, imaging, and hospital charges related to those injuries. METHODS: An IRB-approved retrospective review of patients presenting to our facility following equine-related trauma was conducted. Demographics, mechanism of injury, types and number of imaging exams, approximate radiation dose administered, imaging findings, Injury Severity Score (ISS), rate/length of hospitalization, and approximate cost of care were recorded. RESULTS: A total of 222 patients (161 F:61 M; mean age 38.5 years (range 4-79)) presented to our emergency department following horse-related injury. Mechanisms of injury included the following: fall (n = 186), kick (n = 18), stepped on (n = 9), and other (n = 9). Body part injured included extremity (26.1%), torso (26.6%), spine (25.7%), and head/neck (18.5%). Longer hospital admission, higher expenditure, increased CT/MR imaging, higher ISS, and radiation dose were noted in older patients and those injured by a fall or kick. Head injuries were more frequent following a horse kick (p = 0.006). Spinal and torso injuries were more common in patients older than 54 years (p = < 0.001) and those with falls (p < 0.04). Extremity injuries were more common in older patients (p < 0.001). CONCLUSION: Patient age greater than 54 years and mechanism of injury are strong predictors of the ISS, injury localization, healthcare expenditure, and mean hospital stay. With the exception of obvious minor wounds, full trauma work-ups (CT chest/abdomen/pelvis and cervical spine) are encouraged for equestrian-related injuries in older patients and those injured by a fall.

Ecological change alters the evolutionary response to harvest in a freshwater fish.

Harvesting can induce rapid evolution in animal populations, yet the role of ecological change in buffering or enhancing that response is poorly understood. Here, we developed an eco-genetic model to examine how ecological changes brought about by two notorious invasive species, zebra and quagga mussels, influence harvest-induced evolution and resilience in a freshwater fish. Our study focused on lake whitefish (Coregonus clupeaformis) in the Laurentian Great Lakes, where the species supports valuable commercial and subsistence fisheries, and where the invasion of dreissenid (zebra and quagga) mussels caused drastic shifts in ecosystem productivity. Using our model system, we predicted faster rates of evolution of maturation reaction norms in lake whitefish under pre-invasion ecosystem conditions when growth and recruitment of young to the population were high. Slower growth rates that occurred under post-invasion conditions delayed when fish became vulnerable to the fishery, thus decreasing selection pressure and lessening the evolutionary response to harvest. Fishing with gill nets and traps nets generally selected for early maturation at small sizes, except when fishing at low levels with small mesh gill nets under pre-invasion conditions; in this latter case, evolution of delayed maturation was predicted. Overall, the invasion of dreissenid mussels lessened the evolutionary response to harvest, while also reducing the productivity and commercial yield potential of the stock. These results demonstrate how ecological conditions shape evolutionary outcomes and how invasive species can have a direct effect on evolutionary responses to harvest and sustainability.

Society of Skeletal Radiology 2017 annual meeting summary.

Peer-reviewed abstracts presented at the 2017 Society of Skeletal Radiology (SSR) Annual Meeting were reviewed following oral presentation. Topics felt to be of potential interest to musculoskeletal (MSK) investigators and practicing clinicians are highlighted in this compilation and analysis of the meeting. New concepts regarding MSK imaging and intervention, MSK protocols and techniques and quality improvement are included. ePoster highlights are also presented.