Thomas J. Ellis

Comparison of six radiographic projections to assess femoral head/neck asphericity.

Early radiographic detection of femoroacetabular impingement might prevent initiation and progression of osteoarthritis. The structural abnormality in femoral-induced femoroacetabular impingement (cam type) is frequently asphericity at the anterosuperior head/neck contour. To determine which of six radiographic projections (anteroposterior, Dunn, Dunn/45° flexion, cross-table/15° internal rotation, cross-table/neutral rotation, and cross-table/15° external rotation) best identifies femoral head/neck asphericity, we studied 21 desiccated femurs; 11 with an aspherical femoral head/neck contour and 10 with a spherical femoral head/neck contour. To radiographically quantify femoral head asphericity, we measured the angle where the femoral head/neck leaves sphericity (angle alpha). The aspherical femoral head/neck contours had a greater maximum angle alpha (70°) compared with the spherical head/neck contours (50°). The angle alpha varied depending on the radiographic projection: it was greatest in the Dunn view with 45° hip flexion (71° ± 10°) and least in the cross-table view in 15° external rotation (51° ± 7°). Diagnosis of a pathologic femoral head/neck contour depends on the radiologic projection. The Dunn view in 45° or 90° flexion or a cross-table projection in internal rotation best show femoral head/neck asphericity, whereas anteroposterior or externally rotated cross-table views are likely to miss asphericity. Level of Evidence: Prognostic study, level II-1 (retrospective study). See the Guidelines for Authors for a complete description of levels of evidence.

Surveyed Opinion of American Trauma, Orthopedic, and Thoracic Surgeons On Rib and Sternal Fracture Repair

INTRODUCTION Rib and sternal fracture repair are controversial. The opinion of surgeons regarding those patients who would benefit from repair is unknown. METHODS Members of the Eastern Association for the Surgery of Trauma, the Orthopedic Trauma Association, and thoracic surgeons (THS) affiliated with teaching hospitals in the United States were recruited to complete an electronic survey regarding rib and sternal fracture repair. RESULTS Two hundred thirty-eight trauma surgeons (TRS), 97 orthopedic trauma surgeons (OTS), and 70 THS completed the survey. Eighty-two percent of TRS, 66% of OTS, and 71% of THS thought that rib fracture repair was indicated in selected patients. A greater proportion of surgeons thought that sternal fracture repair was indicated in selected patients (89% of TRS, 85% of OTS, and 95% of THS). Chest wall defect/pulmonary hernia (58%) and sternal fracture nonunion (>6 weeks) (68%) were the only two indications accepted by a majority of respondents. Twenty-six percent of surgeons reported that they had performed or assisted on a chest wall fracture repair, whereas 22% of surgeons were familiar with published randomized trials of the surgical repair of flail chest. Of surgeons who thought rib fracture or sternal fracture repair was rarely, if ever, indicated, 91% and 95%, respectively, specified that a randomized trial confirming efficacy would be necessary to change their negative opinion. CONCLUSIONS A majority of surveyed surgeons reported that rib and sternal fracture repair is indicated in selected patients; however, a much smaller proportion indicated that they had performed the procedures. The published literature on surgical repair is sparse and unfamiliar to most surgeons. Barriers to surgical repair of rib and sternal fracture include a lack of expertise among TRS, lack of research of optimal techniques, and a dearth of randomized trials.

Absorbable Plates for Rib Fracture Repair: Preliminary Experience

BACKGROUND Absorbable prostheses are currently used in a variety of bone reconstructions and fixations. METHODS This is a case series of rib fracture fixation using absorbable plates and screws consisting of 70:30 poly(L-lactide-co-D,L-lactide) from April 2001 through November 2002. RESULTS Ten patients underwent rib fracture fixation with absorbable plates and screws. Indications included flail chest with failure to wean (five patients), acute pain with instability (four patients), and chest wall defect (one patient). All patients with flail chest weaned from mechanical ventilation successfully. All patients with pain and instability reported rapid subjective improvement or resolution. The patient with a chest wall defect repair returned to full athletic activity without limitations at 6 months. Thoracoscopic assistance was used in three cases and muscle-sparing incisions were used in eight cases. Two patients with screw fixation only developed loss of rib fracture reduction. One patient developed a wound infection requiring drainage. The period of follow-up ranged from 3 to 18 months. CONCLUSION Absorbable plates produce good clinical results and are an option for rib fracture repair. Two-point fixation (screw fixation plus suture cerclage) is required. Further refinements in technique should focus on minimally invasive methods.

Screw Position Affects Dynamic Compression Plate Strain in an In Vitro Fracture Model

Objective This investigation considers the effect of a variety of screw positions on plate strain in three fracture models. Design Dynamic compression plate fixation of in vitro fracture models. Methods To model a fracture, a plastic pipe was cut transversely and a twenty-hole dynamic compression plate was attached by screws. Eighteen stacked, rectangular, rosette strain gauges were installed on the plate to evaluate strain. Three models were evaluated: two constructs in which there was no contact between the cut ends of the pipe under the fixation plate (small-and large-gap models) and a construct in which there was direct apposition of the cut ends (no-gap model). The pattern and magnitude of strains were assessed as a function of varying combinations of screw position for each model. Results Maximal plate strain in the gap models was lowest with screws placed closest to the gap, compared with screws placed away from the gap or spaced apart. The no-gap model showed significantly lower strains when screws were placed further from the osteotomy site than when screws were positioned close together or spaced apart. In all cases, maximal plate strain occurred adjacent to the most central screw holes and rapidly dissipated along the length of the plate. Conclusion In a model simulating a comminuted fracture (gap), this study found that screws should be placed as close to the fracture site as possible to minimize plate strain. In an anatomically reduced two-part fracture model (no gap), widely spaced screws or those placed away from the fracture resulted in lower strains.

Biomechanical testing of a novel, minimally invasive rib fracture plating system.

BACKGROUND A novel rib fracture repair plating system was developed to provide durable fixation with a shorter length than standard systems and thus facilitate minimally invasive repair. We hypothesized that U-plate fixation would be at least equivalent in durability to standard anterior fixation. STUDY Twenty fresh frozen ribs (10 pairs) from two human cadavers were first tested for intact stiffness (force or deformation). A gap of 5 mm was then created in the middle of each rib with a saw. Each rib was reconstructed with either the U-plate (4.6 cm length, Acute Innovations, LLC, Hillsboro, OR) with four screws or a 2.4-mm anterior locking plate (9.5 cm length, Synthes, Paoli, PA) with six screws. The U-plates were placed on one rib and the anterior plates on the contralateral rib of the paired levels. The reconstructed ribs were cycled 50,000 times with a load of +/-2N at 1 Hz in a simulation of the repetitive loading of deep breathing. The stiffness of the construct was measured throughout the test. RESULTS Stiffness decreased from the intact rib to the transected/plated rib for both types of fixation; however, a significant decrease in stiffness was observed only with the anterior repair (p = 0.03). After 50,000 cycles, the U-plated ribs lost 0.12 +/- 0.03 N/mm (1.9%) stiffness, whereas the anterior-plated ribs lost 0.72 +/- 0.13 N/mm (9.9%) stiffness (p = 0.001). CONCLUSIONS In this simulation of an unstable rib fracture with a small bony gap, U-plate fixation was more durable than standard anterior fixation. The greatly diminished size of the U-plate compared with the standard may facilitate minimally invasive rib fracture repair.

Hierarchy of evidence: differences in results between non-randomized studies and randomized trials in patients with femoral neck fractures

IntroductionThere have been a number of non-randomized studies comparing arthroplasty with internal fixation in patients with femoral neck fractures. However, there remains considerable debate about whether the results of non-randomized studies are consistent with the results of randomized, controlled trials. Given the economic burden of hip fractures, it remains essential to identify therapies to improve outcomes; however, whether data from non-randomized studies of an intervention should be used to guide patient care remains unclear. We aimed to determine whether the pooled results of mortality and revision surgery among non-randomized studies were similar to those of randomized trials in studies comparing arthroplasty with internal fixation in patients with femoral neck fractures.Materials and methodsWe conducted a Medline search from 1969 to June 2002, identifying both randomized and non-randomized studies comparing internal fixation with arthroplasty in patients with femoral neck fractures. Additional strategies to identify relevant articles included Cochrane database, SCISEARCH, textbooks, annual meeting programs, and content experts. We abstracted information on mortality and revision rates in each study and compared the pooled results between non-randomized and randomized studies. In addition, we explored potential reasons for dissimilar results between the two study designs.ResultsWe identified 140 citations that addressed the general topic of comparison of arthroplasty and internal fixation for hip fracture. Of these, 27 studies met the eligibility criteria, 13 of which were non-randomized studies and 14 of which were randomized trials. Mortality data was available in all 13 non-randomized studies (n=3108 patients) and in 12 randomized studies (n=1767 patients). Non-randomized studies overestimated the risk of mortality by 40% when compared with the results of randomized trials (relative risk 1.44 vs 1.04, respectively). Information on revision risk was available in 9 non-randomized studies (n=2764 patients) and all 14 randomized studies (n=1901 patients). Both estimates from non-randomized and randomized studies revealed a significant reduction in the risk of revision surgery with arthroplasty compared with internal fixation (relative risk 0.38 vs 0.23, respectively). The reduction in the risk of revision surgery with arthroplasty compared with internal fixation was 62% for non-randomized studies and 77% for randomized trials. Thus, non-randomized studies underestimated the relative benefit of arthroplasty by 19.5%. Non-randomized studies with point estimates of relative risk similar to the pooled estimate for randomized trials all controlled for patient age, gender, and fracture displacement in their comparisons of mortality. We were unable to identify reasons for differences in the revision rate results between the study designs.ConclusionsSimilar to other reports in medical subspecialties, non-randomized studies provided results dissimilar to randomized trials of arthroplasty vs internal fixation for mortality and revision rates in patients with femoral neck fractures. Investigators should be aware of these discrepancies when evaluating the merits of alternative surgical interventions, especially when both randomized trials and non-randomized comparative studies are available.

Operative treatment of extra-articular proximal tibial fractures.

Background Extra-articular proximal tibial fractures are often the result of high-energy trauma with displacement and comminution. Most authors agree that operative management of these fractures is warranted to optimize patient outcomes. It is unclear, however, which surgical option (plate, nail, external fixator, or combination) is preferable. 1–17 Objective To evaluate the effect of alternative operative techniques in the management of extra-articular proximal third tibial fractures on rates of nonunion, malunion, infection, compartment syndrome, and implant failure. Highest Available Evidence 1. Intramedullary nail (level 3 prospective case series) 2. Plates (level 3 prospective case series) 3. External fixator (level 4 case series) Study Identification 1. Cochrane Database: 0 articles 2. PubMed Search: Proximal tibial fractures: 568 hits; And external fixation: 69 hits; And plate: 103 hits; And intramedullary nail: 77 hits Clinical queries search: proximal tibial fracture (specificity/therapy): 1 hit; proximal tibial fracture (sensitivity): 24 hits Systematic reviews: 3 hits (none relevant) 3. OTA website abstract database: 8 abstracts Total number potentially relevant articles: 29 (following review of all study titles and abstracts) Total number included after review: 17 (1–17)

Interobserver reliability of a CT-based fracture classification system.

Objectives: This study was designed to determine whether the interobserver reliability of a fracture classification scheme applied based on a single, carefully defined, computed tomography (CT) cut is greater than those previously reported for systems designed for use with plain radiographs. Design: Observer review of selected cases. Setting: Four, level one, trauma centers. Patients: Pretreatment CT scans of patients with calcaneus fractures were screened by the authors. Thirty cases were selected that had an appropriate semicoronal CT image. Ten orthopaedic traumatologists who were members of the Orthopaedic Trauma Association and had a minimum of 5 years postresidency experience were selected as reviewers. Intervention: The reviewers were provided with a digital CT image for each case as well as written and diagrammatic representations of the Sanders classification system. The observers then classified each fracture according to the Sanders classification. Results: The mean kappa value for interobserver reliability for fracture types I-IV was 0.41 ± 0.02 (mean ± standard error of the mean; range, 0.07-0.64). Observers disagreed by more than 1 fracture type (ie, I vs. III or II vs. IV) in 10% of the cases. Observers agreed on the location of the fracture lines (A, B, C) in 90% of type II fractures and 52% of type III fractures. Conclusions: The results indicate that in a carefully controlled paradigm, the interobserver reliability with a classification system based on interpretation of a single, carefully defined CT image was no better than the results reported for the same classification system used with full CT data or for other classification systems used for various fractures in the skeleton. Agreement in identifying the location of the fracture lines was very good for simple fractures but much worse for complex injuries. Additional study may determine whether the use of a full complement of CT images can improve reliability in classification of complex injuries.

Surgical treatment of intertrochanteric hip fractures with associated femoral neck fractures using a sliding hip screw.

Objective: The purpose of this study was to report the results of surgical treatment of a subset of intertrochanteric fractures with posteromedial comminution and extension of the fracture line into the femoral neck using a sliding hip screw. Design: Retrospective review. Setting: Level I county trauma center. Patients: Twenty-nine fractures (8%) with this pattern were identified from 381 intertrochanteric hip fractures treated at a single institution over a 10-year period. Nine patients were excluded (2 died, 7 had incomplete radiographic follow-up), leaving 20 patients for assessment. Intervention: All fractures were treated with a sliding hip screw. Main Outcome Measurements: Radiographs at a mean follow-up of 17 months were recorded as demonstrating: 1) fixation failure; 2) fracture union; or 3) fracture nonunion. The tip-apex distance, amount of lag screw collapse, screw position in the femoral head, and adequacy of reduction were determined. Results: Treatment failed according to these radiographic measures in 5 of 20 (25%) fractures. Failures included fracture nonunion (1 case), lag screw cutout (2 cases), and combined nonunion/lag screw cutout (2 cases). All 5 failures had complete collapse of the lag screw, whereas 4 of the 15 successfully treated fractures had complete collapse. The amount of collapse was significantly greater for the treatment failures (mean, 38 mm) than in the successfully treated hips (mean, 20 mm). There was no significant association between treatment success or failure and tip-apex distance, lag screw position, and adequacy of reduction. Conclusion: We conclude that intertrochanteric hip fractures with associated femoral neck fractures should not be managed with a standard sliding hip screw.

Initial management of pelvic and femoral fractures in the multiply injured patient

The management of polytrauma patients is clinically challenging and requires a multi-disciplinary team approach. The immediate and definitive operative care of fractures represents the optimal treatment for polytrauma patients with orthopedic injuries. Early orthopedic intervention in long bone fractures and pelvic ring injuries has been shown to decrease pulmonary complications, improve hemodynamic stability, reduce ventilator time, and facilitate early patient mobilization. These factors decrease mortality and improve outcomes for patients with multiple injuries.