Irreducible ankle fracture-dislocation due to tibialis anterior subluxation: a case report.

Irreducible ankle fracture-dislocations are rare. Several cases of irreducible ankle fracture-dislocation have been reported in published studies secondary to the tibialis posterior tendon, deltoid ligament, or extensor digitorum longus tendon blocking the reduction. We report a case of irreducible ankle fracture-dislocation resulting from posteromedial subluxation of the tibialis anterior tendon around a medial malleolar fracture fragment. Ultimately, the ankle required open reduction of the incarcerated tendon to reduce the joint and proceed with internal fixation of the associated fracture. The patient's postoperative course was uncomplicated, and the tibialis anterior tendon was functioning at 10 months postoperatively, after which he did not return for follow-up examinations. To our knowledge, this is the first reported case of the tibialis anterior tendon blocking closed reduction of an ankle fracture-dislocation.

Sagittal deformity of Garden type I and II geriatric femoral neck fractures is frequently misclassified by lateral radiographs.

The objective of this study was to determine the validity and inter-rater reliability of radiographic assessment of sagittal deformity of femoral neck fractures. Design: This is a retrospective cohort study. Setting: Level 1 trauma center. Patients/Participants: Thirty-one patients 65 years or older who sustained low-energy, Garden type I/II femoral neck fractures imaged with biplanar radiographs and either computed tomography or magnetic resonance imaging were included. Main Outcome Measurements: Preoperative sagittal tilt was measured on lateral radiographs and compared with the tilt identified on advanced imaging. Fractures were defined as "high-risk" if posterior tilt was ≥20 degrees or anterior tilt was >10 degrees. Results: Of 31 Garden type I/II femoral neck fractures, advanced imaging identified 10 high-risk fractures including 8 (25.8%) with posterior tilt ≥20 degrees and 2 (6.5%) with anterior tilt >10 degrees. Overall, there was no significant difference between sagittal tilt measured using lateral radiographs and advanced imaging (P = 0.84), and the 3 raters had good agreement between their measurements of sagittal tilt on lateral radiographs (interclass correlation coefficient 0.79, 95% confidence interval [0.65, 0.88], P < 0.01). However, for high-risk fractures, radiographic measurements from lateral radiographs alone resulted in greater variability and underestimation of tilt by 5.2 degrees (95% confidence interval [-18.68, 8.28]) when compared with computed tomography/magnetic resonance imaging. Owing to this underestimation of sagittal tilt, the raters misclassified high-risk fractures as "low-risk" in most cases (averaging 6.3 of 10, 63%, range 6 - 7) when using lateral radiographs while low-risk fractures were rarely misclassified as high-risk (averaging 1.7 of 21, 7.9%, range 1 - 3, P = 0.01). Conclusions: Lateral radiographs frequently lead surgeons to misclassify high-risk sagittal tilt of low-energy femoral neck fractures as low-risk. Further research is necessary to improve the assessment of sagittal plane deformity for these injuries. Level of Evidence: Level IV diagnostic study.

Clinical and Radiographic Predictors of Nonunion in Open Tibial Shaft Fractures.

Open fracture is a risk factor for nonunion of diaphyseal tibia fractures. Compared with closed injuries, there is a relative lack of scientific knowledge regarding the healing of open tibia fractures. The objective of this study was to investigate which patient, injury, and surgeon-related factors predict nonunion in open tibial shaft fractures. A cohort of 98 patients with 104 extra-articular open tibial shaft fractures (OTA/AO 41A2-3, 42A-C, and 43A) were treated surgically between 2007 and 2018 at a single level 1 trauma center and were retrospectively reviewed. Patients underwent irrigation and debridement followed by definitive intramedullary nailing or plate fixation. Patient, injury, and perioperative prognostic factors were analyzed as predictors of nonunion based on anteroposterior and lateral radiographs. The nonunion rate was 27.9% (n=29). There were 12 occurrences of deep infection (11.5%). The median follow-up was 14 months. High-energy mechanism of injury (hazard ratio [HR], 5.76), Gustilo-Anderson class IIIA injury (HR, 3.66), postoperative cortical continuity of 0% to 25% (HR, 2.90), early postoperative complication (HR, 4.20), and deep infection (HR, 2.25) were significant predictors of nonunion on univariable analysis (P<.05). On multivariable assessment, only high-energy mechanism of injury, Gustilo-Anderson class IIIA injury, and early postoperative complication reached significance as predictors of nonunion. These data also indicate that lack of cortical continuity is a significant univariable radiographic predictor of nonunion. This is potentially modifiable, may guide surgeons in selecting patients for early bone grafting procedures, and should be assessed carefully in this high-risk population. [Orthopedics. 2021;44(3):142-147.].

Preventing Wedge Deformities When Treating Intertrochanteric Femur Fractures With Intramedullary Devices: A Technical Tip.

Intertrochanteric femur fractures are common injuries associated with significant patient morbidity and mortality and high societal costs. Although intramedullary devices have shown promises for treating a wide range of intertrochanteric femur fractures, improper technique can lead to malalignment, fracture displacement, and/or iatrogenic fractures. In particular, a "wedge effect" has been described, in which the passage of conical reamers and the intramedullary nail itself results in the distraction of intertrochanteric fragments with lateralization of the shaft from the femoral neck and varus malalignment. Here, we describe the mechanism by which this deformity is generated and describe techniques for preventing it, including the use of a modified starting point and an alternative to the conical opening reamers.

Advanced Imaging Lacks Clinical Utility in Treating Geriatric Pelvic Ring Injuries Caused by Low-Energy Trauma.

OBJECTIVES: Is advanced imaging necessary in the evaluation of pelvic fractures caused by low-energy trauma in elderly patients? DESIGN: Retrospective review. SETTING: Single institution, Level 1 Trauma Center. PATIENTS: Age ≥60 years old treated for low-energy traumatic pelvic ring injuries. INTERVENTION: None. MAIN OUTCOMES: Posterior pelvic ring injuries diagnosed on advanced imaging, radiographic displacement, admission status, hospital length of stay, change in weight-bearing status recommendations, and whether operative treatment was pursued. RESULTS: Eighty-seven patients met the inclusion criteria, of which 42 had advanced imaging to evaluate the posterior pelvic ring (10 magnetic resonance imaging, 32 computed tomography). More posterior pelvic ring injuries were identified with advanced imaging compared with radiographs alone (P < 0.001). There was no statistically significant difference in rate of admission (P = 0.5) or hospital length of stay (P = 0.31) between patients with radiographs alone compared with patients evaluated with radiographs plus advanced imaging. The rate of displacement >1 cm at presentation and 6-week follow-up was unaffected by the presence of a posterior injury diagnosed on advanced imaging. Treatment for all 87 patients remained weight-bearing as tolerated with assist device irrespective of advanced imaging findings, and no patient underwent surgical intervention by 12-week follow-up. CONCLUSIONS: Despite frequent identification of posterior pelvic ring injuries in patients evaluated with advanced imaging, admission status, length of hospital stay, radiographic displacement, and treatment recommendations were unaffected by these findings. The use of advanced imaging in elderly patients with low-energy traumatic pelvic ring fractures may not be necessary. LEVEL OF EVIDENCE: Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

A reliable method for intraoperative evaluation of syndesmotic reduction.

OBJECTIVES: To determine the accuracy of a technique for intraoperative assessment of syndesmotic reduction in ankle fractures. DESIGN: Prospective, case series. SETTING: University hospital. PATIENTS/PARTICIPANTS: Eighteen consecutive patients with suspected syndesmotic injuries were enrolled between 2007 and 2009. The diagnosis of syndesmotic injury was based on static ankle radiographs. The study group consisted of 12 male and 6 female patients with an average age of 32 years (range 19-56 years). INTERVENTION: All patients had mortise and talar dome lateral fluoroscopic images obtained of the uninjured ankle in the operating room. The injured ankle underwent operative reduction and provisional fixation using the uninjured ankle radiographs as a template for comparison. An intraoperative computed tomography (CT) scan was obtained to verify the syndesmotic reduction before syndesmotic fixation. If the reduction was not anatomic, the reduction was revised using fluoroscopy and the CT repeated. MAIN OUTCOME MEASUREMENTS: Accuracy of syndesmotic reduction performed using fluoroscopy and confirmed by intraoperative CT scan. RESULTS: Using the technique described, intraoperative CT confirmed anatomic reduction initially in 17 of the 18 fractures. The 1 case where CT did change the course of treatment, revision of fibular fracture reduction resulted in an anatomic reduction of the syndesmosis on repeat CT. CONCLUSIONS: Accurate evaluation of the syndesmotic reduction can be determined intraoperatively using comparison mortise and talar dome lateral fluoroscopic images. Direct visualization of the syndesmosis or CT may not be necessary to achieve an accurate reduction in these injuries.

Three-dimensional analysis of pelvic volume in an unstable pelvic fracture.

BACKGROUND: A model was developed to predict changes in pelvic volume associated with increasing pubic diastasis in unstable pelvic fractures. METHODS: Intact and postfracture pelvic volumes were calculated in 10 cadavers using computerized axial tomography (CT). The true pelvis was assumed to be either a sphere, a cylinder, or a hemi-elliptical sphere. Using the appropriate equations for calculating the volume of each of these shapes, pelvic volume was predicted and then compared with the measured values. RESULTS: The observed volume changes associated with increasing pubic diastasis were much smaller than previously reported. The mean difference between the measured and predicted volume was 20.0 +/- 9.9% for the sphere, 10.7 +/- 6.5% for the cylinder, and 4.5 +/- 5.9% for the hemi-elliptical sphere. The differences between these means were statistically significant (p < 0.001). CONCLUSIONS: This data suggests that the hemi-elliptical sphere best describes the geometric shape of the true pelvis and better predicts quantitative changes in pelvic volume relative to an increasing pubic diastasis as the radius has little effect on the change in volume. Due to the small changes in volume observed with increasing diastasis, factors other than the absolute change in volume must account for the clinically observed effects of emergent pelvic stabilization.

Does screw configuration affect subtrochanteric fracture after femoral neck fixation?

A subtrochanteric femur fracture after cannulated screw fixation of a femoral neck fracture is a devastating complication. We hypothesized that an apex-distal screw orientation would tolerate higher loads to subtrochanteric fracture. Human cadaveric femora were instrumented with three cannulated screws in either an apex-distal or an apex-proximal configuration. Specimens were loaded along the mechanical axis to failure creating a subtrochanteric femur fracture. Ultimate load to failure and the effect of bone density on load to failure were compared between groups. There was a greater load to failure in the apex-distal group compared with the apex-proximal group. The mean force to fracture in the apex-distal group (11,330 N; standard deviation = 3151 N) was greater than the mean force to fracture in the apex-proximal group (7795 N; standard deviation = 3194 N). Previous investigations have shown improved femoral neck fixation with an apex-distal configuration, but none has examined the relationship between screw orientation and subtrochanteric fractures. Our observations support the use of an apex-distal configuration for cannulated screw fixation of femoral neck fractures.