281 research outputs found
Two-week joint mobilization intervention improves self-reported function, range of motion, and dynamic balance in those with chronic ankle instability
We examined the effect of a 2-week anterior-to-posterior ankle joint mobilization intervention on weight-bearing dorsiflexion
range of motion (ROM), dynamic balance, and self-reported function in subjects with chronic ankle instability (CAI). In this prospective
cohort study, subjects received six Maitland Grade III anterior-to-posterior joint mobilization treatments over 2 weeks. Weightbearing
dorsiflexion ROM, the anterior, posteromedial, and posterolateral reach directions of the Star Excursion Balance Test (SEBT),
and self-reported function on the Foot and Ankle Ability Measure (FAAM) were assessed 1 week before the intervention (baseline),
prior to the first treatment (pre-intervention), 24–48 h following the final treatment (post-intervention), and 1 week later (1-week
follow-up) in 12 adults (6 males and 6 females) with CAI. The results indicate that dorsiflexion ROM, reach distance in all directions of
the SEBT, and the FAAM improved (p < 0.05 for all) in all measures following the intervention compared to those prior to the intervention.
No differences were observed in any assessments between the baseline and pre-intervention measures or between the postintervention
and 1-week follow-up measures (p > 0.05). These results indicate that the joint mobilization intervention that targeted
posterior talar glide was able to improve measures of function in adults with CAI for at least 1 week
Ulnar collateral ligament injuries of the thumb: phalangeal translation during valgus stress in human cadavera
BACKGROUND: The clinical diagnosis of thumb ulnar collateral ligament disruption has been based on joint angulation during valgus stress testing. This report describes a definitive method of distinguishing between complete and partial ulnar collateral ligament injuries by quantifying translation of the proximal phalanx on the metacarpal head during valgus stress testing. METHODS: Sixty-two cadaveric thumbs underwent standardized valgus stress testing under fluoroscopy with the ulnar collateral ligament intact, following an isolated release of the proper ulnar collateral ligament, and following a combined release of both the proper and the accessory ulnar collateral ligament (complete ulnar collateral ligament release). Following complete ulnar collateral ligament release, the final thirty-seven thumbs were also analyzed after the application of a valgus force sufficient to cause 45° of valgus angulation at the metacarpophalangeal joint to model more severe soft-tissue injury. Two independent reviewers measured coronal plane joint angulation (in degrees), ulnar joint line gap formation (in millimeters), and radial translation of the proximal phalanx on the metacarpal head (in millimeters) on digital fluoroscopic images that had been randomized. RESULTS: Coronal angulation across the stressed metacarpophalangeal joint progressively increased through the stages of the testing protocol: ulnar collateral ligament intact (average [and standard deviation], 20° ± 8.1°), release of the proper ulnar collateral ligament (average, 23° ± 8.3°), and complete ulnar collateral ligament release (average, 30° ± 8.9°) (p < 0.01 for each comparison). Similarly, gap formation increased from the measurement in the intact state (5.1 ± 1.3 mm), to that following proper ulnar collateral ligament release (5.7 ± 1.5 mm), to that following complete ulnar collateral ligament release (7.2 ± 1.5 mm) (p < 0.01 for each comparison). Radial translation of the proximal phalanx on the metacarpal head did not increase after isolated release of the proper ulnar collateral ligament (1.6 ± 0.8 mm vs. 1.5 ± 0.9 mm in the intact state). There was a significant increase in translation following release of the complete ulnar collateral ligament complex (3.0 ± 0.9 mm; p < 0.01) and an additional increase after forcible angulation of the joint to 45° (4.1 ± 0.9 mm; p < 0.01). Translation 2 mm greater than that in the stressed control was 100% specific for complete disruption of the ulnar collateral ligament complex. CONCLUSIONS: While transection of the proper ulnar collateral ligament leads to an increase in metacarpophalangeal joint angulation and gapping on stress fluoroscopic evaluation, only release of both the accessory and the proper ulnar collateral ligament significantly increases translation of the proximal phalanx on the metacarpal head. CLINICAL RELEVANCE: A finding of phalangeal translation on a stress fluoroscopic image distinguishes partial from complete tears of the thumb ulnar collateral ligament
Plantar Vibrotactile Detection Deficits in Adults with Chronic Ankle Instability
Purpose: The purpose of this study was to investigate the vibrotactile detection thresholds of the plantar cutaneous afferents in subjects with chronic ankle instability compared with healthy control subjects. Methods: Eight adults with chronic ankle instability and eight adults with no ankle sprain history participated. Vibrotactile detection thresholds were assessed using a mechanical stimulus generator system, mounted onto an articulated microscope arm, which delivered sinusoidal vibrotactile inputs to the foot sole at three different sites: head of the first metatarsal, base of the fifth metatarsal, and the heel. Vibrotactile stimulation was delivered at a range of test frequencies that corresponded to the known responsiveness of cutaneous mechanoreceptors in the glabrous skin of the foot sole (10, 25, and 50 Hz). Probe displacement measures (dB) from the last eight displacement trials that contained 50% positive detection responses were averaged to obtain a single threshold estimate for each test frequency and site combination. Results: The results of this study indicate that no significant group-by-site interactions were found for any test frequencies (P \u3e 0.29). However, group main effects were present at the 10-Hz (P \u3c 0.0001), 25-Hz (P = 0.03), and 50-Hz (P = 0.04) test frequencies, indicating that subjects with chronic ankle instability had significantly higher detection thresholds or less sensitivity when stimulation sites were pooled. Conclusions: The results of this study indicate that subjects with chronic ankle instability may demonstrate decreased sensitivity on the plantar surface of the foot. These alterations in plantar cutaneous somatosensation may help explain the underlying mechanisms associated with the prolonged sensorimotor system impairments in postural control and gait commonly exhibited by people with chronic ankle instability
Lineage divergence detected in the malaria vector Anopheles marajoara (Diptera: Culicidae) in Amazonian Brazil
<p>Abstract</p> <p>Background</p> <p>Cryptic species complexes are common among anophelines. Previous phylogenetic analysis based on the complete mtDNA <it>COI </it>gene sequences detected paraphyly in the Neotropical malaria vector <it>Anopheles marajoara</it>. The "Folmer region" detects a single taxon using a 3% divergence threshold.</p> <p>Methods</p> <p>To test the paraphyletic hypothesis and examine the utility of the Folmer region, genealogical trees based on a concatenated (<it>white </it>+ 3' <it>COI </it>sequences) dataset and pairwise differentiation of <it>COI </it>fragments were examined. The population structure and demographic history were based on partial <it>COI </it>sequences for 294 individuals from 14 localities in Amazonian Brazil. 109 individuals from 12 localities were sequenced for the nDNA <it>white </it>gene, and 57 individuals from 11 localities were sequenced for the ribosomal DNA (rDNA) internal transcribed spacer 2 (ITS2).</p> <p>Results</p> <p>Distinct <it>A. marajoara </it>lineages were detected by combined genealogical analysis and were also supported among <it>COI </it>haplotypes using a median joining network and AMOVA, with time since divergence during the Pleistocene (<100,000 ya). <it>COI </it>sequences at the 3' end were more variable, demonstrating significant pairwise differentiation (3.82%) compared to the more moderate 2.92% detected by the Folmer region. Lineage 1 was present in all localities, whereas lineage 2 was restricted mainly to the west. Mismatch distributions for both lineages were bimodal, likely due to multiple colonization events and spatial expansion (~798 - 81,045 ya). There appears to be gene flow within, not between lineages, and a partial barrier was detected near Rio Jari in Amapá state, separating western and eastern populations. In contrast, both nDNA data sets (<it>white </it>gene sequences with or without the retention of the 4th intron, and ITS2 sequences and length) detected a single <it>A. marajoara </it>lineage.</p> <p>Conclusions</p> <p>Strong support for combined data with significant differentiation detected in the <it>COI </it>and absent in the nDNA suggest that the divergence is recent, and detectable only by the faster evolving mtDNA. A within subgenus threshold of >2% may be more appropriate among sister taxa in cryptic anopheline complexes than the standard 3%. Differences in demographic history and climatic changes may have contributed to mtDNA lineage divergence in <it>A. marajoara</it>.</p
1,050 years of hurricane strikes on Long Island in the Bahamas
© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Wallace, E. J., Donnelly, J. P., van Hengstum, P. J., Winkler, T. S., McKeon, K., MacDonald, D., d'Entremont, N. E., Sullivan, R. M., Woodruff, J. D., Hawkes, A. D., & Maio, C. 1,050 years of hurricane strikes on long island in the Bahamas. Paleoceanography and Paleoclimatology, 36(3), (2021): e2020PA004156, https://doi.org/10.1029/2020PA004156.Sedimentary records of past hurricane activity indicate centennial-scale periods over the past millennium with elevated hurricane activity. The search for the underlying mechanism behind these active hurricane periods is confounded by regional variations in their timing. Here, we present a new high resolution paleohurricane record from The Bahamas with a synthesis of published North Atlantic records over the past millennium. We reconstruct hurricane strikes over the past 1,050 years in sediment cores from a blue hole on Long Island in The Bahamas. Coarse-grained deposits in these cores date to the close passage of seven hurricanes over the historical interval. We find that the intensity and angle of approach of these historical storms plays an important role in inducing storm surge near the site. Our new record indicates four active hurricane periods on Long Island that conflict with published records on neighboring islands (Andros and Abaco Island). We demonstrate these three islands do not sample the same storms despite their proximity, and we compile these reconstructions together to create the first regional compilation of annually resolved paleohurricane records in The Bahamas. Integrating our Bahamian compilation with compiled records from the U.S. coastline indicates basin-wide increased storminess during the Medieval Warm Period. Afterward, the hurricane patterns in our Bahamian compilation match those reconstructed along the U.S. East Coast but not in the northeastern Gulf of Mexico. This disconnect may result from shifts in local environmental conditions in the North Atlantic or shifts in hurricane populations from straight-moving to recurving storms over the past millennium.This work was funded by the National Science Foundation Graduate Research Fellowship (to E. J. W.), the Dalio Explore Foundation, and National Science Foundation grant OCE-1356708 (to J. P. D. and P. J. vH.)
Spontaneous infection of a stable mediastinal cystic mass: A case report
Mediastinal cysts have an unpredictable course but can cause complications such as infection or local pressure effects. Persons with mediastinal cysts can be asymptomatic for many years or can develop symptoms as a result of complications of the cyst. There is a lack of consensus on the best approach to managing those patients without symptoms. In this case report, a 56 year old woman with an indolent mediastinal cyst initially managed conservatively suddenly developed symptoms suggestive of an infected mediastinal cyst requiring surgical resection
Historically unprecedented Northern Gulf of Mexico hurricane activity from 650 to 1250 CE
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Rodysill, J. R., Donnelly, J. P., Sullivan, R., Lane, P. D., Toomey, M., Woodruff, J. D., Hawkes, A. D., MacDonald, D., d'Entremont, N., McKeon, K., Wallace, E., & van Hengstum, P. J. Historically unprecedented Northern Gulf of Mexico hurricane activity from 650 to 1250 CE. Scientific Reports, 10(1), (2020): 19092. doi:10.1038/s41598-020-75874-0.Hurricane Michael (2018) was the first Category 5 storm on record to make landfall on the Florida panhandle since at least 1851 CE (Common Era), and it resulted in the loss of 59 lives and $25 billion in damages across the southeastern U.S. This event placed a spotlight on recent intense (exceeding Category 4 or 5 on the Saffir-Simpson Hurricane Wind Scale) hurricane landfalls, prompting questions about the natural range in variability of hurricane activity that the instrumental record is too short to address. Of particular interest is determining whether the frequency of recent intense hurricane landfalls in the northern Gulf of Mexico (GOM) is within or outside the natural range of intense hurricane activity prior to 1851 CE. In this study, we identify intense hurricane landfalls in northwest Florida during the past 2000 years based on coarse anomaly event detection from two coastal lacustrine sediment archives. We identified a historically unprecedented period of heightened storm activity common to four Florida panhandle localities from 650 to 1250 CE and a shift to a relatively quiescent storm climate in the GOM spanning the past six centuries. Our study provides long-term context for events like Hurricane Michael and suggests that the observational period 1851 CE to present may underrepresent the natural range in landfalling hurricane activity.Funding for this project was provided by the Strategic Environmental Research and Development Program (SERDP) grant and NSF awards 0903020, 1902463, and 1854980 awarded to Jeffrey Donnelly, and the USGS Land Change Science Program
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