Anterior Tibial Artery Danger Zone During Anterolateral Plate Fixation of the Distal Tibia: A 3D Computed Tomography Angiogram Modeling Study.

OBJECTIVES: The objective of this study was to define the danger zone at which the anterior tibial artery (ATA) is at risk during anterolateral plating of the distal tibia using a novel 3D computed tomography angiography (CTA) modeling technique. METHODS: 116 patients (232 lower extremities) who underwent lower extremity CTAs between April 2020 and April 2022 were identified. Those with lower extremity trauma, evidence of a previously healed tibial fracture, or poor visualization of the ATA were excluded. The remaining 150 lower extremities (92 patients) were modeled with an anterolateral distal tibia plate using Sectra IDS7 software. The distance of the ATA from bony landmarks was measured perpendicular to the level at which the vessel intersected the plate. RESULTS: The ATA intersected the plate proximally at a mean distance of 10.5 cm (95% confidence intervals, 10.2-10.9) and at a mean distance of 4.6 cm (95% confidence intervals, 4.4-4.9) distally from the central tibial plafond. The ATA intersected with the plate as far distal as hole number 1 and as proximal as hole 14 of the plate. The greatest injury risk was associated with plate holes 3-8. In this region, the artery was at risk in 46-99 percent of specimens. CONCLUSIONS: The ATA is at risk when screws are placed percutaneously in an anterolateral distal tibia plate. The artery can be as close as 4.4 cm and as far as 10.9 cm proximal to the tibial plafond when crossing the plate, correlating to a risk of injury to the ATA at plate holes 1 through 14.

Ambulation Distance Within 72 Hours after Surgical Management Is a Predictor of 90-Day Ambulatory Capacity in Elderly Patients with Hip Fracture.

INTRODUCTION: The inability to mobilize after surgical intervention for hip fractures in the elderly is established as a risk factor for greater morbidity and mortality. Previous studies have evaluated the association between the timing and distance of ambulation in the postoperative acute care phase with postoperative complications. The purpose of this study was to evaluate the association between ambulatory distance in the acute postoperative setting and ambulatory capacity at 3 months. METHODS: Patients aged 65 and older who were ambulatory at baseline and underwent surgical intervention for hip fractures from 2014 to 2019 were retrospectively reviewed. Consistent with previous literature, patients were divided into two groups: those who were able to ambulate 5 feet within 72 hours after surgical fixation (early ambulatory) and those who were not (minimally ambulatory). RESULTS: One hundred seventy patients (84 early ambulatory and 86 minimally ambulatory) were available for analysis. Using a multivariable ordinal logistic regression model, variables found to be statistically significant predictors of ambulatory status at 3 months were the ability to ambulate five feet in 72 hours (P < 0.0001), ambulatory distance at discharge (P = 0.012), and time from presentation to surgery (P = 0.039). Patients who were able to ambulate 5 feet within 72 hours had 9 times the odds of being independent ambulators rather than a lower ambulatory class (cane, walker, and nonambulatory). Pertrochanteric fractures were less likely than femoral neck fractures to independently ambulate at 3 months (17.2% vs. 42.3%; P = 0.0006). DISCUSSION: Ambulating 5 feet within 72 hours after hip fracture surgery is associated with an increased likelihood of independent ambulation at 3 months postoperatively. This simple and clear goal may be used to help enhance postoperative mobility and independence while providing a metric to guide therapy and help counsel patients and families.

Do associated proximal fibula fractures help predict the severity of tibial plateau fractures?

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.

Can Laser-Assisted Indocyanine Green Angiography Be Used to Quantify Perfusion Changes During Staged Fixation of Pilon Fractures? A Pilot Study.

OBJECTIVE: To quantify soft tissue perfusion changes in pilon fractures during staged treatment using laser-assisted indocyanine green angiography (LA-ICGA). SETTING: Level 1 trauma center. DESIGN: Prospective cohort study. PATIENTS/PARTICIPANTS: Twelve patients with 12 pilon fractures participated in the study. Seven patients had OTA/AO classification of 43-C3, 3 had 43-C2, and 2 had 43-B2. MAIN OUTCOME MEASURES: LA-ICGA was performed with the SPY fluorescence imaging platform. Analysis via ImageJ was used to generate a fractional area of perfusion (FAP) based on fluorescent intensity to objectively quantify soft tissue perfusion. Anterior, medial, and lateral measurements were performed at the time of initial external fixation (EF) application and then at the time of definitive fixation. RESULTS: FAP within the region of interest was on average 64% medially, 61% laterally, and 62% anteriorly immediately before EF placement. Immediately before definitive open reduction internal fixation, fractional region of interest perfusion was on average 86% medially, 87% laterally, and 86% anteriorly. FAP increased on average 24% medially ( P = 0.0004), 26% laterally ( P = 0.001), and 19% anteriorly ( P = 0.002) from the time of initial EF to the time of definitive open reduction and internal fixation. CONCLUSIONS: Quantitative improvement in soft tissue perfusion was identified through the course of staged surgical management in pilon fractures. LA-ICGA potentially may be used to determine appropriate timing for definitive surgical intervention based on the readiness of the soft tissue envelope. Ultimately, these findings may influence clinical outcomes with respect to choice of surgical approach, soft tissue management, surgical timing, and wound healing. LEVEL OF EVIDENCE: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

An Anatomic Study of the Lateral Dorsal Cutaneous Nerve Using 3-Tesla MRI: A Comparison to Cadaveric Data With Surgical Applications.

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.

Intervertebral disc kinematics in active duty Marines with and without lumbar spine pathology.

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.

Lumbar spine angles and intervertebral disc characteristics with end-range positions in three planes of motion in healthy people using upright MRI.

Understanding changes in lumbar spine (LS) angles and intervertebral disc (IVD) behavior in end-range positions in healthy subjects can provide a basis for developing more specific LS models and comparing people with spine pathology. The purposes of this study are to quantify 3D LS angles and changes in IVD characteristics with end-range positions in 3 planes of motion using upright MRI in healthy people, and to determine which intervertebral segments contribute most in each plane of movement. Thirteen people (average age = 24.4 years, range 18-51 years; 9 females; BMI = 22.4 ±â€¯1.8 kg/m2) with no history of low back pain were scanned in an upright MRI in standing, sitting flexion, sitting axial rotation (left, right), prone on elbows, prone extension, and standing lateral bending (left, right). Global and local intervertebral LS angles were measured. Anterior-posterior length of the IVD and location of the nucleus pulposus was measured. For the sagittal plane, lower LS segments contribute most to change in position, and the location of the nucleus pulposus migrated from a more posterior position in sitting flexion to a more anterior position in end-range extension. For lateral bending, the upper LS contributes most to end-range positions. Small degrees of intervertebral rotation (1-2°) across all levels were observed for axial plane positions. There were no systematic changes in IVD characteristics for axial or coronal plane positions.