Communicating Branches of the Facial Nerve: Descriptions and Clinical Considerations.

BACKGROUND: Major branching patterns of the facial nerve have been extensively studied because damage to branches of the nerve is associated with complications ranging from weakness to paralysis. However, communicating branches of the facial nerve have received far less attention despite being hypothesized as a means of motor recovery following facial nerve injury. OBJECTIVES: The aim of this study was to characterize the frequency of communicating branches of the facial nerve to provide clarity on their anatomy and clinical correlations. METHODS: Bilateral facial dissections were completed on cadaveric donors (n = 20) to characterize the frequency and location of communicating branches across terminal branches of the facial nerve. Statistical analyses were employed to analyze differences between the location of communications by side and whether the communicating branches were more likely to occur on the left or right side (P < 0.05). RESULTS: Communicating branches were identified among all terminal branches of the facial nerve and their frequencies reported. The highest frequencies of communicating branches were identified between the buccal-to-marginal mandibular and zygomatic-to-buccal branches, at 67.5% (27 comm/40 hemifaces). The second highest frequency was identified between the temporal-to-zygomatic branches in 62.5% (25/40) of donors. The marginal mandibular-to-cervical branches had communicating branches at a frequency of 55% (22/40). Location or sidedness of communicating branches did not significantly differ. CONCLUSIONS: Our characterization more accurately defines generalizable areas in which communicating branches are located. These locations of branches, described in relation to nearby landmarks, are fundamental for clinical and surgical settings to improve procedural awareness.

Key Anatomical Clarifications for the Marginal Mandibular Branch of the Facial Nerve: Clinical Significance for the Plastic Surgeon.

BACKGROUND: The marginal mandibular branch (MMBr) of the facial nerve is the least likely to recover from injury due to infrequent anastomosis with other branches. The MMBr has been described as coursing superior to the inferior border of the mandible. However, studies have reported variations in its location in embalmed and fresh specimens. It has been postulated that the embalming process may effect its anatomic position. OBJECTIVES: The aim of this study was to re-evalulate the location of the MMBr relative to the inferior border of the mandible in both fresh and embalmed cadavers, and investigate variation in its position with sex, side of the face, and age. METHODS: Superficial fascial planes were dissected to reveal the MMBr and its anatomic relations. Distance between the most inferior branch of the MMBr and the antegonial notch were measured bilaterally. The most inferior position of the MMBr between the antegonial notch and gonion was measured. Fresh heads were used as a comparison, with an additional measurement taken of the distance between the MMBr and the gonial angle. RESULTS: The MMBr was located inferior to the border of the mandible (90.3%) more often than above (9.6%). No significant differences were found between fresh and embalmed cadavers, sex, side of body, or age (P > 0.05). No significant difference was found between intact cadavers and fresh heads (P > 0.05). CONCLUSIONS: This study confirms and describes reliable landmarks for safety zones for the MMBr during plastic and reconstructive surgery of the lower face and upper neck. These data add reliability to studies that have investigated nerve locations in embalmed cadavers.

Osteopathic Manipulative Treatment as an Intervention to Reduce Stress, Anxiety, and Depression in First Responders: A Pilot Study.

In this pilot study, we examined the efficacy of Osteopathic Manipulative Treatment (OMT) for improving symptoms of stress, anxiety, and depression (SAD) to determine a correlation between overall improvement in health and quality of life for first responders. Participants received weekly OMT or sham OMT targeting autonomic imbalance. Indicators of SAD were examined pre- and post-study. Overall, this pilot study suggests improvement in both the social-psychological (mental) self-assessments, and alterations in SAD-associated biomarkers from OMT.

Battle of the sections: Student outcomes and course feedback support combined prosection and dissection laboratory formats to maximize student success.

Gross anatomy laboratories frequently utilize dissection or prosection formats within medical curricula. Practical examination scores are consistent across the formats, yet these examinations assessed larger anatomical structures. In contrast, a single report noted improved scores when prosection was used in the hand and foot regions, areas that are more difficult to dissect. The incorporation of prosected donors within "Head and Neck" laboratories provided an opportunity to further characterize the impact of prosection in a structurally complex area. Retrospective analysis of 21 Head and Neck practical examination questions was completed to compare scores among cohorts that utilized dissection exclusively or incorporated prosection. Mean scores of practical examination questions were significantly higher in the prosection cohort (84.27% ± 12.69) as compared with the dissection cohort (75.59% ± 12.27) (p < 0.001). Of the 12 questions that performed better in the prosection cohort (88.42% ± 8.21), 10 items mapped to deeper anatomical regions. By comparison, eight of nine questions in the dissection cohort outperformed (88.44% ± 3.34) the prosection cohort (71.74% ± 18.11), and mapped to anatomically superficial regions. Despite the mean score increase with positional location of the questions, this effect was not statically significant across cohorts (p = 1.000), suggesting that structure accessibility in anatomically complex regions impacts performance. Student feedback cited structure preservation (71.5%) and time savings (55.8%) as advantages to prosection; however, dissection was the perceived superior and preferred laboratory format (88.6%). These data support combined prosection and dissection formats for improving student recognition of deeply positioned structures and maximizing student success.

Anatomy of the sural nerve complex: Unaccounted anatomic variations and morphometric data.

BACKGROUND: The sural nerve (SN) is a cutaneous sensory nerve innervating the posterolateral leg. The SN is formed from a highly variable set of contributing nerves called the sural nerve complex (SNC). The SNC is made up of the lateral sural cutaneous nerve, medial sural cutaneous nerve, sural communicating branch, and SN. The SN is frequently cited as the most common donor nerve graft and is commonly injured in procedures of the lower extremity. Recent meta-analysis standardized six morphologies of the SNC and established a required reporting criterion for the group of nerves forming the SN. Due to the inconsistencies in previous literature, this study will group observed SNC's by one of these six SNC morphologies to assess and validate the meta-analysis grouping criteria. This study will also collect the same morphometric data previously outlined in order to grow the number of samples that are reported in a standardized fashion. METHODS: 100 formalin and 4 Theil preserved cadavers (n = 208) lower limbs were bilaterally dissected at Kansas City University and Creighton University School of Dentistry to observe the SNC in its entirety on the posterolateral leg. Anatomic data was captured utilizing the standardized morphologies types 1-6 with two sub-typing. Nerves that were found to be outside of this categorization were placed in an unassigned grouping. RESULTS: The most prevalent SNCs were type 1 at 41.35% (n = 86) and type 3 nerves at 34.62% (n = 72). Type 2 was found 8.65% (n = 18), type 4 and 5 were found each at 0.48% (n = 1). Type 6 was not observed. When comparing the present studies frequency of nerve types 1-6 to the meta-analysis a sub-grouping of "North American" cadaveric studies a X2 = .903 p = .030 was found. Two distinct and previously unassigned formations of the SNC were 10.58% (n = 20) and 3.85% (n = 8) of data. These two SNC are termed type 7 & 8, these represent two formations of SN that are outside of what was previously reported. 15.87% (n = 33) did not match visual descriptions based on nerve origin of a type 1 SNC but met written definitions. These were termed type 1A1 and type 1A2. The SNC was asymmetrical in 57.69% (n = 120). The pooled mean length of the SN was 32.97 ± 14.12 cm (31.05-34.88), mean diameter was 2.31 ± 0.83 mm (2.20-2.42, and the distance of the posterior border of the lateral malleolus to the SN was found to be 1.72 ± 0.70 cm (1.63-1.80). CONCLUSION: Anatomic variation in the SNC is highly variable, yet is consistent with previously observed literature. This study demonstrates two unaccounted formations of the SNC as well as two additional subcategories of SNC that were not included in the previous meta-analysis. These four variants warrant inclusion as standard formations of the SNC due to the high prevalence observed in this study as well as historical consistency observed in previous literature and case reports. These two SNC formations increase the risk of iatrogenic injury during surgical interventions of the lower extremity. Morphometric data describing the spatial relationship of this nerve complex on the posterolateral leg is consistent with previously reported data and aids in generating a large data set for future studies to characterize spatial properties of this nerve complex.