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Background: The lateral dorsal cutaneous nerve (LDCN) and the anastomotic branch of the sural nerve (AB) are cutaneous sensory nerves at risk of iatrogenic injury during lateral foot surgery. This study is the first to use a large cohort of high-resolution magnetic resonance images (MRIs) of the ankle to better describe the course of these nerves in vivo in order to aid surgeons intraoperatively. Our study intends to build on the “high and inside” approach to the proximal 5MT by accounting for variations in course of the LDCN and AB. Methods: One hundred twenty-five 3-tesla (T) MRI studies of the ankle were analyzed. Three reviewers measured the distance from the LDCN and AB to landmarks including the most proximal aspect of the fifth metatarsal tuberosity (5MT) and the peroneus brevis tendon (PBT). Results: Mean vertical distance from the LDCN to the 5MT was 0.8 ± 0.2 cm. Presence of an AB was visualized in 59 of 125 studies (47.2%) and was found 2.2 ± 0.5 cm dorsal to the 5MT. The AB was found to become superior to PBT at a horizontal distance 1.9 ± 0.5 cm proximal to the 5MT. The LDCN was found superior to the PBT at its insertion onto the 5MT in approximately 10% (n = 12) of our studies. During these instances, the LDCN was located an average of 0.3 cm dorsal to the PBT. Conclusion: Our proposed “safe zone” for the approach to the proximal 5MT remains superior to the LDCN and inferior to the AB and avoids crossing directly over either nerve in >95% of analyzed MRI studies. This incision begins 1.5 cm dorsal to the most proximal aspect of the 5MT and extends no more than 1 cm posteriorly. Careful dissection and identification of the LDCN and possible AB is necessary prior to further extension of incision. Level of Evidence: Level IV, case series.

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Purpose Proximal fibula fractures are often associated with tibial plateau fractures, but their relationship is poorly characterized. The purpose of this study was to better define the relationship between tibial plateau injury severity and presence of associated soft tissue injuries. Methods A retrospective review was performed on all operatively treated tibial plateau fractures at a Level 1 trauma center over a 5-year period. Patient demographics, injury radiographs, CT scans, operative reports and follow-up were reviewed. Results Queried tibial plateau fractures from 2014 to 2019 totaled 217 fractures in 215 patients. Fifty-two percent were classified as AO/OTA 41B and 48% were AO/OTA 41C. Thirty-nine percent had an associated proximal fibula fracture. The presence of a proximal fibula fracture had significant correlation with AO/OTA 41C fractures, as compared with AO/OTA 41B fractures (chi-square, p < 0.001). Of the patients with a lateral split depression type tibial plateau fracture, the presence of a proximal fibula fracture was associated with more articular comminution, measured by number of articular fragments (mean = 4.0 vs. 2.9 articular fragments, p = 0.004). There was also a higher rate of meniscal injury in patients with proximal fibula fractures (37% vs. 20%, p = 0.003). Conclusions There was a significant relationship between the higher energy tibial plateau fracture type (AO/OTA 41C) and the presence of an associated proximal fibula fracture. The presence of a proximal fibula fracture with a tibial plateau fracture is an indicator of a higher energy injury and a higher likelihood of meniscal injury.

Military members are required to carry heavy loads frequently during training and active duty combat. We investigated if operationally relevant axial loads affect lumbar disc kinematics in forty‐one male active duty Marines with no previous clinically diagnosed pathology. Marines were imaged standing upright with and without load. From T2‐weighted magnetic resonance images, intervertebral disc (IVD) health and kinematic changes between loading conditions and across lumbar levels were evaluated using two‐way repeated measures analysis of variance tests. IVD kinematics with loading were compared between individuals with and without signs of degeneration on imaging. Linear regression analyses were performed to determine associations between IVD position and kinematic changes with loading. Fifty‐eight percent (118/205) of IVDs showed evidence of degeneration and 3% (7/205) demonstrated a disc bulge. IVD degeneration was not related to posterior annular position ( P > .205). Changes in sagittal intervertebral angle were not associated with changes in posterior annular position between baseline and loaded conditions at any lumbar level ( r < 0.267; P = .091‐.746). Intervertebral angles were significantly larger in the lower regions of the spine ( P < .001), indicating increased local lordosis when moving in the caudal direction Disc height at the L5/S1 level was significantly smaller (6.3 mm, mean difference = 1.20) than all other levels ( P < .001) and baseline posterior disc heights tended to be larger at baseline (7.43 mm ± 1.46) than after loading (7.18 ± 1.57, P = .071). Individuals with a larger baseline posterior annular position demonstrated greater reduction with load at all levels ( P < .002), with the largest reductions at L5/S1 level. Overall, while this population demonstrated some signs of disc degeneration, operationally relevant loading did not significantly affect disc kinematics.