Morphometry of the fibular collateral ligament: anatomic study with comprehensive review of the literature.

There is no consensus in the literature related to the morphology, bony attachments, and variations of the fibular collateral ligament (FCL) of the knee. Our purpose was to investigate FCL morphology and to review reports in the literature regarding this structure. Seventy knees from formalin-fixed, adult cadavers were dissected and a digital caliper was used to measure FCL length, width, distance from proximal attachment to articular surface (PA→AS), and distance from distal attachment to articular surface (DA→AS). The mean (SE) length and width of all FCLs was 48.3 (1.1) mm and 4 (0.16) mm, respectively. The mean (SE) PA→AS and DA→AS of all FCLs was 22 (0.8) mm and 24.8 (1) mm, respectively. We found a direct relationship between the PA→AS and DA→AS distances (Spearman rho = 0.527, P = 0.002) and this association was independent of age and sex. Two FCL variations were found: a bifurcate ligament with two distal bands and a trifurcate ligament with three distal bands, all of which attached to the fibular head. Our literature review revealed that only 2/10 cadaveric FCL morphology studies reported variations similar to the current study. Further, there was variability in the reported location of the FCL proximal attachment. When combining our data with these studies, 105/219 FCLs directly attached to the apex of the lateral epicondyle (LE), 10/219 to a fovea posterior to the LE, and 104/219 posterior and proximal to the LE. These data may have implications related to FCL injury and repair.

Virulence characteristics of Gram-positive bacteria isolated from diabetic foot ulcers.

Diabetic wound infections including diabetic foot ulcers (DFUs) are a major global health concern and a leading cause of non-traumatic amputations. Numerous bacterial species establish infection in DFUs, and treatment with antibiotics often fails due to widespread antibiotic resistance and biofilm formation. Determination of bacterial species that reside in DFU and their virulence potential is critical to inform treatment options. Here, we isolate bacteria from debridement tissues from patients with diabetes at the University of Colorado Anschutz Medical Center. The most frequent species were Gram-positive including Enterococcus faecalis, Staphylococcus aureus, and Streptococcus agalactiae, also known as Group B Streptococcus (GBS). Most tissues had more than one species isolated with E. faecalis and GBS frequently occurring in polymicrobial infection with S. aureus. S. aureus was the best biofilm producing species with E. faecalis and GBS isolates exhibiting little to no biofilm formation. Antibiotic susceptibility varied amongst strains with high levels of penicillin resistance amongst S. aureus, clindamycin resistance amongst GBS and intermediate vancomycin resistance amongst E. faecalis. Finally, we utilized a murine model of diabetic wound infection and found that the presence of S. aureus led to significantly higher recovery of GBS and E. faecalis compared to mice challenged in mono-infection.

Group B Streptococcus adaptation promotes survival in a hyperinflammatory diabetic wound environment.

Diabetic wounds have poor healing outcomes due to the presence of numerous pathogens and a dysregulated immune response. Group B Streptococcus (GBS) is commonly isolated from diabetic wound infections, but the mechanisms of GBS virulence during these infections have not been investigated. Here, we develop a murine model of GBS diabetic wound infection and, using dual RNA sequencing, demonstrate that GBS infection triggers an inflammatory response. GBS adapts to this hyperinflammatory environment by up-regulating virulence factors including those known to be regulated by the two-component system covRS, such as the surface protein pbsP, and the cyl operon, which is responsible for hemolysin/pigmentation production. We recover hyperpigmented/hemolytic GBS colonies from the murine diabetic wound, which we determined encode mutations in covR. We further demonstrate that GBS mutants in cylE and pbsP are attenuated in the diabetic wound. This foundational study provides insight into the pathogenesis of GBS diabetic wound infections.

Anatomic study of the suboccipital artery of Salmon with surgical significance.

The anatomy of the muscular branches of the vertebral arteries has clinical relevance during surgical procedures, suboccipital injections, and manual therapies. Each vertebral artery is divided into four segments. Segment V3, found in the suboccipital triangle, courses posteromedially around the lateral mass to lie in a groove on the posterior arch of the atlas, ultimately coursing beneath the posterior atlanto-occipital membrane to enter the skull. Although not always present, any muscular branch that emanates from this segment to supply the suboccipital muscles is called the suboccipital artery of Salmon. There is a paucity of literature on this artery despite its clinical relevancy. We found the suboccipital artery of Salmon in 10 (67%) of 15 embalmed adult cadavers. This frequency is considerably higher than that in previous reports. Two (20%) of the 10 cadavers demonstrated bilateral and symmetrical suboccipital arteries of Salmon (one artery on each side). Four (40%) of the 10 cadavers had an arrangement of two parallel suboccipital arteries of Salmon on one side, and one on the contralateral side. Three (30%) of the 10 cadavers displayed an asymmetrical unilateral arrangement (only one artery). One (10%) of the 10 cadavers displayed the unique arrangement of three arteries of Salmon on one side and one artery on the contralateral side. This study adds to a limited, but growing, body of knowledge by providing photographic evidence of the course and arrangement of these arteries and, therefore, can be of value to surgeons and other clinicians whose procedures focus on the suboccipital region.

An Investigation of Diabetes Knowledge Levels Between Newly Diagnosed Type 2 Diabetes Patients in Galway, Ireland and New York, USA: A Cross-Sectional Study.

Management of diabetes mellitus (DM) involves podiatrists as the primary practitioners engaged in prevention and treatment of lower limb pathology. Patients must first possess adequate knowledge to engage in effective self-management. A knowledge assessment of a DM cohort has never before been conducted in Ireland. The primary research objective was to determine the existence of gaps in specific areas of DM-related knowledge between type 2 DM (T2DM) patients in Galway (GW) and New York (NY). A cross-sectional study compared DM-related knowledge levels between 2 cohorts over a 10-week period. Participants were recently (<3 years) diagnosed with T2DM, were based in general podiatry clinics in GW or NY and had no current or previous diabetic foot ulceration (DFU) or other DM-related foot pathology. Participants were recruited by convenience sampling. A purpose-designed 28-item closed questionnaire was completed by both cohorts to assess knowledge differences. Fifty-two subjects were recruited (GW, n = 32; NY, n = 20). The mean age was 61 ± 10 years; 56% were male. Significant differences were found between cohorts relating to individual questions; specifically regarding knowledge of glycemic control (P = .002) and frequency of self-monitoring of blood glucose (P = .003). Inappropriate foot care practices across both cohorts were highlighted. No significant intercohort differences in particular survey sections were identified. The scores in the systemic and podiatric sections of the questionnaire highlight patterns of common health misconceptions and some highly inappropriate foot care practices respectively across the entire sample. In particular, the dearth of patient awareness regarding uncontrolled blood glucose and its relationship to DFU development, amputation, and associated morbidity is shown to be an area of concern; this must be addressed a priori.

Anatomic study of the deltoid ligament of the ankle.

BACKGROUND: There is heterogeneity in the literature regarding the anatomy and number of ligamentous bands that form the deltoid ligament (DL). Anatomic knowledge of the DL and its variations are important for surgeons who repair ankle fractures. METHODS: The DL was dissected in 33 ankles from 17 formalin-fixed cadavers (mean age at death, 76.6 years) to examine its morphology. The length, width, and thickness of its constituent bands were recorded with a digital caliper. Descriptive and correlational statistics were used to investigate the relationships between band size, age at death, and sex. A literature review was conducted to compare our data to those of previous studies. RESULTS: The DL has superficial and deep layers with up to 8 different bands. CONCLUSION: The DL stabilizes the medial ankle and should be evaluated in flatfoot deformities and severe ankle fractures. CLINICAL RELEVANCE: Anatomic knowledge of DL variations should aid the surgeon in repairing torn DLs.

The transverse occipital ligament: an anatomic, histologic, and radiographic study.

BACKGROUND CONTEXT: The craniocervical region is an osteoligamentous complex that provides structural stability and movement by means of numerous ligaments. Fundamental knowledge of these ligaments is important for physicians who treat patients with disorders of this region to reduce morbidity and mortality. There is a paucity of data in the literature regarding the morphology, function, and classification of the transverse occipital ligament (TOL). PURPOSE: The purpose of this study was to investigate the prevalence, morphology, and variations of the TOL in a large number of adult human cadavers using dissection, histology, and digital radiography. STUDY DESIGN: Cadaveric laboratory study. SAMPLE: Thirty-two formalin-fixed human adult cadavers were dissected in the study. Fourteen cadavers were found to have a TOL. OUTCOME MEASURES: Measurements using a digital caliper, high-resolution digital photography, histologic staining with bright-field microscopy, and digital radiography. METHODS: The posterior musculature and related soft tissues were dissected and underlying bony elements removed. The TOL was identified, isolated, measured, and then removed for histologic preparation with hematoxylin and eosin staining. Anteroposterior open-mouth digital radiographs of the upper cervical spine with monofilament attached to the TOL were used to demonstrate its relations to the occiput, atlas, and axis. RESULTS: The TOL was present in 14 of 32 (44%) of the dissected cadavers (six male and eight female). Three types of TOLs were identified. Type 1 had bilateral connections to the alar ligaments and had fibers inserting onto the dens. Type 2 also had bilateral connections to the alar ligaments but did not have fibers inserting onto the dens. Type 3 neither had any connections to the alar ligaments nor had fibers that connected to the dens. Male cadavers always had a Type 1 TOL compared with 3 of 8 (38%) female cadavers and this difference was significant (p=.031). The TOL consisted of dense regular connective tissue with parallel arrangements of collagen fibers and interposed fibroblasts. CONCLUSIONS: Our data suggest that the TOL is not an anatomic variant and can be classified into three types. Future biomechanical studies can be designed to investigate the function of the TOL, although we hypothesize that it may act as a fulcrum during flexion and extension of the head because it is located between the apical ligament and superior crus of the cruciform ligament. Anteroposterior open-mouth digital radiographs revealed the location of the TOL with respect to the upper two cervical vertebrae. Future research should investigate the radiologic characteristics of the TOL using magnetic resonance imaging.