Superior gluteal artery injury risk from third sacral segment transsacral screw insertion.

OBJECTIVES: Iliosacral (IS) and transsacral (TS) screws are commonly used to stabilize pelvic ring injuries. The course of the superior gluteal artery (SGA) can be close to implant insertion paths. The third sacral segment (S3) has been described as a viable osseous fixation pathway (OFP) but the proximity of the SGA to the S3 screw path is unknown. METHODS: Fifty uninjured patients with contrasted pelvic computed tomograms (CTA) were identified with an S3 path large enough for a 7.0 mm TS screw. Starting sites for S1 IS or TS, S2 and S3 TS screws were located on the volume rendered lateral CTA image and transferred onto the surface rendered 3D CTA with the SGA clearly visible. The distance from screw start sites to the SGA was measured. A distance less than 3.5 mm was considered likely for injury. RESULTS: The average distances from screw start sites to the SGA were 23.0 ± 7.9 mm for S1 IS screws, 14.3 ± 6.4 mm for S2 TS screws and 25.9 ± 6.5 mm for S3 TS screws. No S1 IS screws, 5 S2 TS screws (10%), and no S3 TS screws were projected to cause injury to the SGA. CONCLUSIONS: The osseous start site and soft tissue path for an S3 TS screw is remote from the SGA. The S1 IS and S3 TS pathways are further away from the SGA while the S2 TS pathway is closer and may theoretically pose a higher injury risk in patients with an available S3 OFP.

Posterior pelvic ring bone density with implications for percutaneous screw fixation.

BACKGROUND: Although the second (S2) and third (S3) sacral segments have been established as potential osseous fixation pathways for screw fixation, the S2 body has been demonstrated to have inferior bone density when compared to the body of the first (S1) sacral segment. Caution regarding the use of iliosacral screws at this level has been advised as a result. As transiliac-transsacral screws traverse the lateral cortices of the posterior pelvis, they may be relying on bone with superior density for purchase, which could obviate this concern. The objective of this study was to compare the bone density of the posterior ilium and sacroiliac joint to that of the sacral body at the first (S1), second (S2), and third (S3) sacral levels. MATERIALS AND METHODS: A retrospective case series was performed, reviewing the CT scans of 100 patients without prior pelvic trauma. Each CT was confirmed to have available osseous fixation pathways at the first (S1), second (S2), and third (S3) sacral segments. The bone density of the posterior ilium/sacroiliac joint (PISJ) and sacral body (SB) was measured using the embedded standardized Hounsfield units (HU) tool at each sacral level. RESULTS: The average S2 PISJ bone density (320.1) was significantly higher than the S1 (286.5) and S3 (278.9) PISJ (p < 0.0001) and S1 and S3 PISJ was not statistically different. The S1 sacral body bone density (231.1) was significantly higher than the S2 (182.1) and S3 (126.8) bone density (p < 0.0001). The PISJ bone density is greater than the sacral body at every sacral level (p < 0.0001). CONCLUSION: The S2 PISJ bone density is significantly greater than S1. The S1, S2, and S3 PISJ bone density is greater than the sacral body at all sacral levels, and the S1 body has higher bone density than the S2 and S3 bodies. These differences in bone density may have implications for the stability of posterior pelvic ring fixation constructs with regard to screw purchase. LEVEL OF EVIDENCE: Level III-Case cohort series.

Fractures of the Calcaneus.

Calcaneal fractures are potentially devastating injuries. To effectively manage calcaneal fractures, surgeons must understand the anatomy of the calcaneus as well as the surgical techniques necessary to restore normal biomechanics of the foot. Surgeons also must understand calcaneal fracture patterns and classifications; initial management techniques, surgical indications and rationale, temporizing management techniques, surgical approaches, definitive management techniques, and postoperative management for calcaneal fractures; as well as outcomes and common complications of calcaneal fractures.

Associated Injuries in Skeletally Immature Children with Pelvic Fractures.

BACKGROUND: Pediatric pelvic fractures are rare injuries resulting from high-energy mechanisms that warrant an extensive work-up for associated injuries. OBJECTIVES: We performed a retrospective study to review concomitant injuries in children who suffered a pelvic fracture and have an open triradiate cartilage. METHODS: Using a database, pediatric pelvic fractures presenting to the authors' institution were extracted. Radiographs and computed tomography scans were reviewed, ensuring that triradiate cartilages were not fused and the pelvic injuries were classified using the Modified Torode Classification. Epidemiologic data extracted included Glasgow Coma Scale (GCS), Injury Severity Score (ISS), and Abbreviated Injury Score (AIS). RESULTS: Sixty patients met the inclusion criteria, and their average age was 8.3 years (range 2-14 years). There were no mortalities. The most common mechanism of injury was a vehicle striking a pedestrian. There were no significant correlations between GCS, ISS, and AIS. All 60 children (100%) suffered extremity injuries. Nineteen patients required surgical orthopedic intervention, and 6 required operative stabilization of the pelvis. Patients who were struck by a motor vehicle were more likely to have multiple pelvic fractures (p < 0.05). Patients with multiple pelvic fractures were more likely to require orthopaedic surgical intervention and require a blood transfusion (p < 0.05). Patients who had type III-B or IV fractures were more likely to require a transfusion than patients with III-A fracture (p < 0.05). CONCLUSIONS: Patients sustaining fractures to an immature pelvis are likely to have additional injuries, which may be fatal or disabling if not diagnosed in a timely manner.

The pubic midline exposure for symphyseal open reduction and plate fixation.

BACKGROUND: Open reduction and plate fixation of the disrupted symphysis pubis is commonly performed through a horizontal Pfannenstiel incision. Certain clinical situations that complicate the soft tissue conditions of the lower abdomen may make the Pfannenstiel incision a less appealing option. We report on the use of a vertical pubic area midline skin incision in a series of patients undergoing open reduction and plate fixation of their traumatically disrupted symphysis pubis. MATERIALS AND METHODS: Institutional Review Board approval was obtained for a retrospective chart review of the charts of 25 patients treated between September 2011 and October 2012. Their charts were reviewed for patient age, gender, body mass index (BMI), pelvic injury type (as classified by Young and Burgess), mechanism of injury and associated traumatic injuries. The depth of the approach was estimated using the pelvic computed tomography (CT) scan. Details from the operative procedure were recorded, as was the length of follow-up and any perioperative complications. RESULTS: Twenty-five patients were eligible for inclusion during the defined study time period between September 2011 and October 2012. The patients' average age was 55.8 years (range 25-91). All patients were males. The average BMI was 29.3 (range 18.8-43.8). The depth measured on the axial pelvic CT scan from skin to symphysis was 57.6 mm (range 35.2-90.2 mm). Five of 25 patients had an isolated pelvic ring injury without other associated injuries. The injury pattern was APC2 in 18, APC3 in 3, LC2 in 2, LC3 in 1 and VS in 1 patient(s) [anterior posterior compression (APC), lateral compression (LC), vertical shear (VS)]. Urologic procedures were performed in the same surgical setting in four patients. The average blood loss was 244 ml (range 150-400 ml). The average follow-up was 2.5 months (range 1-12 months). Perioperative issues were noted in two patients. One patient died within a month of surgery as a result of his associated traumatic injuries. One patient developed a deep infection. CONCLUSION: The pubic midline skin exposure is a feasible alternative to the Pfannenstiel incision for open reduction and plate fixation of the pubic symphysis. LEVEL OF EVIDENCE: IV, Retrospective case series.

Antioxidants protect from atherosclerosis by a heme oxygenase-1 pathway that is independent of free radical scavenging.

Oxidative stress is implicated in atherogenesis, yet most clinical trials with antioxidants, particularly vitamin E, have failed to protect against atherosclerotic diseases. A striking exception is probucol, which retards atherosclerosis in carotid arteries and restenosis of coronary arteries after angioplasty. Because probucol has in vitro cellular-protective effects independent of inhibiting lipid oxidation, we investigated the mode of action of probucol in vivo. We used three models of vascular disease: apolipoprotein E-deficient mice, a model of atherosclerosis; rabbit aortic balloon injury, a model of restenosis; and carotid injury in obese Zucker rats, a model of type 2 diabetes. Unexpectedly, we observed that the phenol moieties of probucol were insufficient, whereas its sulphur atoms were required for protection. Probucol and its sulphur-containing metabolite, but not a sulphur-free phenolic analogue, protected via cell-specific effects on inhibiting macrophage accumulation, stimulating reendothelialization, and inhibiting vascular smooth muscle cell proliferation. These processes were mediated via induction of heme oxygenase-1 (HO-1), an activity not shared by vitamin E. Our findings identify HO-1 as the molecular target of probucol. They indicate 2-electron rather than radical (1-electron) oxidants as important contributors to atherogenesis, and point to novel lead compounds for therapeutic intervention against atherosclerotic diseases.

Perioperative Impact of Early Limited Surgical Intervention to Treat Pilon Fractures.

BACKGROUND: The operative treatment of pilon fractures is classically treated with a staged protocol with ankle spanning external fixator, followed by definitive open reduction and internal fixation in order to decrease risk of soft tissue complications and infection. However, treatment of pilon fractures with patrial tibial fixation in addition to ankle spanning external fixation at the time of index procedure may facilitate final fixation while avoiding complications that were associated with acute definitive fixation. METHODS: Retrospective cohort series of 113 patients treated for pilon fractures from September 2012 to November 2018 at a single level 1 trauma center. Charts were reviewed to compare patients who underwent traditional management with a staged protocol and those who had a limited tibial reduction and fixation (LTRF) during the index procedure. The main outcome measurement was time to definitive fixation. RESULTS: Twenty-six percent of patients (29 of 113) had limited tibial reduction and fixation (LTRF) during index surgery. Mean time between index procedure and definitive ORIF was 4.75 days less for LTRF cohort compared to standard stage cohort (10.86 ± 7.44 vs. 15.61 ± 8.59 days, P = .009). The index procedure took on average 51 minutes longer in the LTRF cohort (P < .001), yet definitive procedure operative time was decreased by an average of 98 minutes (P < .001), and overall (index plus definitive) operative duration was shortened by an average of 50 minutes (P = .044). There was no difference in rate of infection between LTRF (3.1%) and traditional treatment (2.5%) (P = .86) or reduction quality (P = .270). There were no nonunions in either treatment group. CONCLUSION: Patients who had LTRF had quicker time to definitive ORIF and decreased operative time for definitive ORIF. There was no difference in infection rate, reduction quality, or nonunion rate between groups. LEVEL OF EVIDENCE: Level IV, Retrospective Cohort Study.

Distal Humerus Traction Radiographs: Is the Interobserver and Intraobserver Reliability Comparable With Computed Tomography?

OBJECTIVES: To compare the interobserver and intraobserver reliability of traction radiographs with 2-dimensional computed tomography (2D CT) in distal humerus fracture classification and characterization. DESIGN: Randomized controlled radiographic review of retrospectively collected data. SETTING: Academic Level 1 trauma center. PATIENTS/PARTICIPANTS: Skeletally mature patients with intra-articular distal humerus fractures with both traction radiographs and CT scans were reviewed by 11 orthopaedists from different subspecialties and training levels. INTERVENTION: The intervention involved traction radiographs and 2D CT. MAIN OUTCOME MEASUREMENTS: The main outcome measurements included interobserver and intraobserver reliability of fracture classification by the OTA/AO and Jupiter-Mehne and determination of key fracture characteristics. RESULTS: For the OTA/AO and Jupiter-Mehne classifications, we found a moderate intraobserver agreement with both 2D CT and traction radiographs (κ = 0.70-0.75). When compared with traction radiographs, 2D CT improved the interobserver reliability of the OTA/AO classification from fair to moderate (κ = 0.3 to κ = 0.42) and the identification of a coronal fracture from slight to fair (κ = 0.2 to κ = 0.34), which was more pronounced in a subgroup analysis of less-experienced surgeons. When compared with 2D CT, traction radiographs improved the intraobserver reliability of detecting stable affected articular fragments from fair to substantial (κ = 0.4 to κ = 0.67). CONCLUSIONS: Traction radiographs provide similar diagnostic characteristics as 2D CT in distal humerus fractures. For less-experienced surgeons, 2D CT may improve the identification of coronal fracture lines and articular comminution.

Orthopaedic trauma during COVID-19: Is patient care compromised during a pandemic?

BACKGROUND: The Coronavirus disease-2019 (COVID-19) placed unprecedented pressure on the healthcare system. Many institutions implemented a government-mandated restructured set of safety and administrative protocols to treat urgent orthopaedic trauma patients. The objective of this study was to compare two cohorts of patients, a COVID group and non-COVID control group, and to evaluate the effectiveness of safety measures outlined in the Rutgers Orthopaedic Trauma Patient Safety Protocol (ROTPSP). Secondary outcomes were to elucidate risk factors for complications associated with fractures and COVID-19. METHODS: Patients treated for orthopaedic traumatic injuries were retrospectively identified between March and May 2020, and compared to a series of patients from the same time period in 2018. Main outcome measures included surgical site infections (SSI), length of stay (LOS), post-operative LOS (poLOS), presentation to OR time (PORT), and length of surgery. RESULTS: After review, 349 patients (201 non-COVID, 148 COVID) undergoing 426 surgeries were included. Average LOS (11.91 days vs. 9.27 days, p = 0.04), poLOS (9.68 days vs. 7.39 days, p = 0.03), and PORT (30.56 vs. 25.59 h, p < 0.01) was significantly shorter in the COVID cohort. There were less SSI in the COVID group (5) compared to the non-COVID group (14) (p = 0.03). Overall complications were significantly lower in the COVID group. Patients receiving Cepheid tests had significantly shorter LOS and poLOS compared to patients receiving the RNA and DiaSorin tests (p < 0.01 and p < 0.01, respectively). The Cepheid test carried the best benefit-to-cost ratio, 0.10, p < 0.05. CONCLUSION: The restructuring of care protocols caused by COVID-19 did not negatively impact perioperative complication rates, PORT or LOS. Cepheid COVID test type administered upon admission plays an integral role in a patient's hospital course by reducing both length of stay and hospital costs. This information demonstrates we can continue to treat orthopaedic trauma patients safely during the COVID-19 pandemic by utilizing strict safety protocols.

Patella fracture fixation with a non-locked anterior plating technique: A biomechanical study.

OBJECTIVES: The purpose of this study was to compare the biomechanical attributes of patella fracture fixation with either anterior plating utilizing two parallel, longitudinal 2.0 mm plates technique versus a cannulated screw tension band technique. METHODS: Five matched pairs (ten specimens) of fresh frozen cadavers were utilized. A transverse patella fracture (OTA 34C1.1) was fixed using either two 4.0 mm cannulated screw anterior tension band (CATB) or with two 2.0 mm stainless steel non-locking plates along the anterior cortex secured with 2.4 mm cortical screws traversing the fracture site. Specimens underwent 1000 cycles of simulated active knee range of motion before load to failure destructive testing. RESULTS: During cyclic loading there were no failures in the plate fixation group, and 2 out of 5 specimens catastrophically failed in the CATB group (p = 0.22). Average fracture displacement at the end of fatigue testing was 0.96 mm in the plate fixation group and 2.72 mm in the CATB group (p = 0.18). The specimens that withstood cyclic testing underwent a destructive load. Mean load to failure for the plate fixation specimens was 1286 N, which was not significantly different from the CATB group mean of 1175 N (p = 0.48). The mechanism of failure in the plate fixation cohort was uniformly via a secondary vertical patella fracture around the plates in all five specimens. In the CATB group, the mechanism of failure was via wire elongation and backing out of the screws. CONCLUSIONS: Patella fixation with anterior plating technique statistically performed equivalent to cannulated screw anterior tension band in ultimate load to failure strength and fatigue endurance under cyclical loading. No failures were observed cyclic simulated active range of motion in the anterior plate group. There was a trend towards improved fatigue endurance in the plate fixation group, however this did not reach statistical significance. We believe plate fixation technique represents a low-profile implant option for treatment of transverse patella fractures, which may allow for early active range of motion, and these data support biomechanical equivalency to standard of care.

External Fixator-Assisted Reduction of Distal Femur Fractures: A Technical Trick.

SUMMARY: Restoration of anatomical alignment while preserving the soft-tissue envelope around the fracture site remains a challenge during distal femur fracture fixation. Although the lateral distal femoral locking plate allows surgeons to achieve adequate bony stability, their application has been associated with malalignment leading to inferior outcomes. We propose a biologically friendly, percutaneous technique that sequentially reduces and aligns distal femur fractures with an anterior external fixator before definitive fixation with a lateral distal femoral locking plate.

Veno-arterial extracorporeal membrane oxygenation for high-risk cardiac catheterisation procedures.

Extracorporeal membrane oxygenation (ECMO) provides circulatory or respiratory support, or both, to patients with severe but potentially reversible cardiac or respiratory failure refractory to standard therapy. The use of ECMO in the paediatric cardiac surgical population is established. Likewise, the use of ECMO for severe adult respiratory failure has recently been established and has been the subject of recent clinical trials. However, its use as a means of cardiac support in the adult population is not routine in clinical practice. We herein review the indications, technical procedure, complications and outcomes of extracorporeal membrane oxygenation as pertinent to cardiac disease in general, and specifically, to catheter-based interventions. We describe two cases of high-risk cardiac catheterisation laboratory procedures performed with veno-arterial ECMO support in adult patients who were deemed to be at unacceptably high risk for conventional open-heart surgery and cardiopulmonary bypass.

Operative Versus Nonoperative Outcomes of Middle-Third Clavicle Fractures: A Systematic Review and Meta-Analysis.

OBJECTIVES: Middle third clavicle fractures have long been managed conservatively with immobilization. Some patients, especially those with completely displaced or shortened clavicle fractures are now thought to have increased risk of nonunion or symptomatic malunion. The authors performed a meta-analysis to study the incidence of nonunion and symptomatic malunion and test the hypothesis that surgical fixation of these fractures significantly lowers the risk of these complications. METHODS: A search was performed in the PubMed, Embase, and Cochrane Library databases for randomized clinical trials and quasi-experimental trials that compare outcomes of operative and nonoperative management for clavicle fractures that are fully (100%) displaced or have greater than 2 cm of shortening. Pooled patient data were used to construct forest plots for the meta-analysis. RESULTS: Eleven studies including 497 patients who were treated and 457 patients treated conservatively were analyzed. Patients managed operatively had significantly lower relative risk of developing nonunion [0.17 (95% confidence interval 0.08-0.33)] and symptomatic malunion [0.13 (95% confidence interval 0.05-0.37)]. Plate fixation significantly reduced the risk of nonunion, but intramedullary nail fixation did not. There was no difference in Constant-Murley or DASH scores between the 2 treatment groups or in the rate of secondary operative procedures. CONCLUSIONS: Patients who undergo operative fixation of displaced middle-third clavicle fractures have a lower incidence of nonunion and symptomatic malunion. The clinical significance of this effect is uncertain, as functional scores were similar in both groups. Further research into the risk factors for nonunion and symptomatic malunion will be necessary to determine which patients benefit from operative fixation. LEVEL OF EVIDENCE: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Posttraumatic Avascular Necrosis After Proximal Femur, Proximal Humerus, Talar Neck, and Scaphoid Fractures.

Posttraumatic avascular necrosis (AVN) is osteonecrosis from vascular disruption, commonly encountered after fractures of the femoral neck, proximal humerus, talar neck, and scaphoid. These locations have a tenuous vascular supply; the diagnosis, risk factors, natural history, and treatment are reviewed. Fracture nonunion only correlates with AVN in the scaphoid. In the femoral head, the risk is increased for displaced fractures, but the time to surgery and open versus closed treatment do not seem to influence the risk. Patients with collapse are frequently symptomatic, and total hip arthroplasty is the most reliable treatment. In the humeral head, certain fracture patterns correlate with avascularity at the time of injury, but most do not go on to develop AVN due to head revascularization. Additionally, newer surgical approaches and improved construct stability appear to lessen the risk of AVN. The likelihood of AVN of the talar body rises with increased severity of talar injury. The development of AVN corresponds with a worse prognosis and increases the likelihood of secondary procedures. In proximal pole scaphoid fractures, delays in diagnosis and treatment elevate the risk of AVN, which is often seen in cases of nonunion. The need for vascularized versus nonvascularized bone grafting when repairing scaphoid nonunions with AVN remains unclear.

The Role of the Computed Tomographic Scan in the Diagnosis of Acetabular Fracture in the Immature Pelvis.

OBJECTIVES: We present a series of skeletally immature patients sustaining acetabular fractures. We hypothesized that if the secondary ossification centers of the acetabulum are not completely ossified, fractures often will not be identified on plain radiography. Our objective was to determine the efficacy of diagnostic plain radiography in these patients. DESIGN: Retrospective case series. SETTING: Urban, level-I trauma center. PATIENTS/PARTICIPANTS: Skeletally immature patients with acetabular fractures following blunt force trauma. INTERVENTION: We obtained a dedicated axial computed tomographic (CT) scan of the pelvis with sequential sections of 2.5-mm thickness. MAIN OUTCOME MEASURES: The accuracy of plain radiography as compared with CT in diagnosing acetabular fractures in skeletally immature patients. RESULTS: Fourteen patients with 16 fractures of the acetabulum were identified by CT scan; however, 69% (11 of 16) were not visible on plain radiography. Radiographs were less likely to identify acetabular fractures compared with pelvic ring fractures [31% (5/16) vs. 92% (11/12); odds ratio, 0.04; 95% confidence interval, 0.01-0.37; P = 0.001]. Patients younger than 12 years were less likely to have acetabular fractures identified on plain radiography [9% (1/11) vs. 80% (4/5); odds ratio, 0.03; 95% confidence interval 0.01-0.59; P = 0.013]. The mean age of patients whose acetabular fractures were not identified on plain radiography was less than those whose fractures were identified on plain radiography (7.6 ± 2.9 vs. 12.8 ± 1.6; P = 0.004). Acetabular fractures visible on plain radiography were more likely to require operative stabilization [60% (3/5) vs. 0% (0/11); P = 0.004]. CONCLUSIONS: In skeletally immature patients with suspected injury to the pelvis, particularly in patients younger than 12 years, diagnostic evaluation using plain radiographs alone may lead to missed injuries. If an acetabular fracture is identified, patients should be followed closely both clinically and radiographically to ensure early identification of any developing posttraumatic deformity. LEVEL OF EVIDENCE: Level IV; Diagnostic-Investigating a diagnostic test.

Plantar Medial Avulsion Fragment Associated With Tongue-Type Calcaneus Fractures.

BACKGROUND: The plantar fascia attaches to the tuberosity of the calcaneus, which produces a distinct plantar medial avulsion (PMA) fracture fragment in certain calcaneal fractures. We hypothesized that tongue-type fractures, as described by the Essex-Lopresti classification, were more likely to be associated with this PMA fracture than joint depression fractures. METHODS: A retrospective chart review was performed at 2 distinct Level I trauma centers to identify patients sustaining calcaneal fractures. Radiographs were then reviewed to determine the Essex-Lopresti classification, OTA classification, and presence of a PMA fracture. RESULTS: The review yielded 271 total patients with 121 (44.6%) tongue-type (TT), 110 (40.6%) joint depression (JD), and 40 (14.8%) fractures not classifiable by the Essex-Lopresti classification. In the TT group, 73.6% of the patients had the PMA fracture whereas only 8.2% of JD and 15.0% of nonclassifiable fractures demonstrated a PMA fragment ( P < .001). CONCLUSION: Plantar medial avulsion fractures occurred in 38.4% of the calcaneal fractures reviewed with a significantly greater proportion occurring in TT (73.6%) as opposed to JD (8.2%). Given the plantar fascia attachment to the PMA fragment, there may be clinical significance to identifying this fracture and changing treatment management; however, this requires further investigation. LEVEL OF EVIDENCE: Level III, comparative study.

Determinants of coronary arterial flow-mediated dilatation following percutaneous coronary intervention.

OBJECTIVE: It has previously been observed that coronary diameter may increase following relief of flow-limiting obstruction. Flow mediated dilatation (FMD) is a fundamental adaptive mechanism for arteries, which is dependent on intact endothelial function. We thus aimed to characterize whether the degree of this flow-mediated dilatation was related to risk factors, which may impair endothelial function. DESIGN: We measured coronary diameter with quantitative angiography before and after relief of chronic total or subtotal (>or=99%) occlusion in 171 patients, in which TIMI-0 or TIMI-1 flow was rapidly restored to TIMI-3 (with attendant increase in flow hypothesized to result in FMD). PATIENTS: Of the 171 patients, 73% were male, 62% were current or ex-smokers, 47% were diabetic, 53% had hypertension, 64% had dyslipidemia (documented hypercholesterolemia or total cholesterol >5.0 mg/dL) and 65% were taking statin therapy. RESULTS: Mean vessel diameter was 2.8 +/- 0.7 mm and flow-mediated dilatation measured 15.1% +/- 20.1% in target vessel, compared with 1.6 +/- 3.1 in control vessels (P < 0.05). FMD was strongly and inversely related to baseline vessel diameter (r = -0.48, P < 0.001). The degree of vessel dilation correlated negatively with the presence of diabetes (r = -0.33, P < 0.001), smoking (r = -0.30, P < 0.001) and extent of coronary artery disease (CAD, r = -0.17, P = 0.01) and positively with the use of statins (r = 0.27, P = 0.001). These factors, apart from extent of CAD, remained significant predictors of FMD on multivariate analysis. CONCLUSIONS: FMD occurs in human coronary arteries following restoration of flow. The magnitude of FMD appears related to vascular risk factors and their treatment.

Saphenous vein grafts display poor endothelium-dependent and endothelium-independent dilation--implications for the pathogenesis of vein graft atherosclerosis.

OBJECTIVE: As endothelial dysfunction has been implicated in the pathogenesis of late failure of saphenous vein grafts (SVG), we assessed endothelium-dependent and endothelium-independent vascular responses of SVG in humans. METHODS: Subjects undergoing angiography after bypass grafting had selective infusions of acetylcholine (ACh, an endothelium-dependent dilator) and sodium-nitroprusside (SNP, an endothelium-independent dilator) into a non-obstructed vein graft. SVG diameters were measured by quantitative coronary angiography. Two matched groups of control subjects, with or without coronary artery disease (CAD), were studied after similar infusions into their femoral arteries. RESULTS: We assessed 10 subjects with SVG, 8 controls with and 8 without CAD. SVG dilatation to high-dose ACh was 5+/-3%, similar to the femoral arteries of subjects with CAD (10+/-5%), but significantly less than the ACh-related arterial dilatation in the non-CAD group (16+/-2%, p=0.02). Similarly, dilatation of SVG after SNP infusion was 9+/-3%, which was not significantly different from the nitrate responses of femoral arteries in the CAD group (21+/-5%), but significantly poorer than in the non-CAD subjects (27+/-5%, p=0.02). CONCLUSION: Saphenous vein bypass grafts display poor endothelium-dependent and endothelium-independent vascular responses in vivo, compared with healthy systemic arteries. This may contribute to the pathogenesis of accelerated atherosclerosis seen in SVG.

Is S3 a Viable Osseous Fixation Pathway?

OBJECTIVES: To report the incidence of patients with a third sacral segment (S3) osseous fixation pathway (OFP) that could accommodate a transiliac-transsacral screw. DESIGN: Retrospective case series. SETTING: Regional Level 1 Trauma Center. PATIENTS/PARTICIPANTS: A total of 250 patients without pelvic trauma from January 2017 to February 2017 were included. INTERVENTION: The axial and sagittal reconstruction images of each patient's computed abdomen and pelvis tomography (CT) scans were reviewed. MAIN OUTCOME MEASUREMENTS: Each CT was evaluated for the presence of sacral dysmorphism and whether an S3 OFP that could accommodate an intraosseous transiliac-transsacral screw exists. RESULTS: There were 130 of the 250 patients (52%) with sacral dysmorphism. Overall, 38 of the 250 patients (15.2%) had an S3 OFP that could accommodate a 7.0-mm transiliac-transsacral style screw. When narrowed to patients who had an S3 OFP, 38 of 153 patients (24.8%) could accommodate a 7.0-mm transiliac-transsacral screw. Specific to the 38 patients with an adequate S3 OFP, 34 of 38 patients (89.5%) were noted to have sacral dysmorphism. CONCLUSIONS: Our study demonstrates that 15.2% of patients have an S3 OFP large enough to accommodate an intraosseous implant. Patients who have sacral dysmorphism are more likely to have an adequate S3 OFP. Additional studies are needed to quantify the S3 OFP, understand the bone quality of the S3 segment and accompanying biomechanical implications, and investigate the anatomical concerns associated with S3 screw placement. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

The Incidence of Posterior Malleolar Involvement in Distal Spiral Tibia Fractures: Is it Higher than We Think?

OBJECTIVES: To investigate the incidence of concomitant posterior malleolar fractures (PMFs) in operative, distal-third, spiral tibia fractures. DESIGN: Prospective protocol with retrospective review of data. SETTING: Single, Level 1 trauma center. PATIENTS/PARTICIPANTS: One hundred ninety-three consecutive, skeletally mature patients with operatively treated fractures of the distal-third, tibial shaft and metaphysis. Pilon fractures were excluded. INTERVENTION: Computed tomography (CT) scans were obtained in all distal-third, spiral fractures of the tibia to determine fracture morphology and presence of a PMF. MAIN OUTCOME MEASUREMENTS: The incidence of concurrent PMFs in operative spiral fractures of the distal tibia. RESULTS: Twenty-six distal-third, spiral fractures were identified with an ipsilateral PMF diagnosed in 92.3% of cases (24 cases). PMFs were over 25 times more likely to occur in distal-third, spiral fractures when compared with other distal-third fracture patterns (relative risk = 25.7, 95% confidence interval, 11.6-56.8). PMFs were treated with supplemental fixation in 23/24 (95.8%) cases. CONCLUSIONS: There is a high incidence of concomitant, ipsilateral fractures of the posterior malleolus in patients presenting with operative distal-third, spiral fractures of the tibia. A preoperative ankle computed tomography should be strongly considered in all cases with this specific fracture morphology. LEVEL OF EVIDENCE: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.