Iliac dysmorphism: defining radiographic characteristics and association with pelvic osseous corridor size.

INTRODUCTION: Insertion of iliac wing implants requires understanding of the curvilinear shape of the ilium. This study serves to quantitatively identify the area of iliac inner-outer table convergence (IOTC), characterize the iliac wing osseous corridor, and define the gluteal pillar osseous corridor. METHODS: Computed tomography scans of 100 male and 100 female hemipelves were evaluated. The iliac wing was studied using manual best-fit analysis of the bounds of the inner and outer cortices. The IOTC was defined as the location of the iliac wing with an intercortical width less than 5 mm. The shortest distance from the apex of the iliac crest to the superior border of the IOTC was defined as the iliac wing osseous corridor. Finally, the width of the gluteal pillar corridor from the gluteus medius tubercle to the ischial tuberosity was measured. RESULTS: The IOTC is an elliptical area measuring 22.3 cm2. All ilia had an area where the inner and outer cortices converged to an intercortical width of less than 5 mm; 48% converged to a single cortex. The shortest mean distance from the superior edge of the iliac crest to the beginning of the IOTC was 20.3 mm in men and 13.8 mm in women (p < 0.001). The gluteal pillar diameter averaged 5.3 mm in men and 4.3 mm in women (p < 0.001). DISCUSSION: All ilia converge to a thin and frequently unicortical central region. A 4.5 mm iliac wing lag screw will not breach the cortex if it remains within 20 mm or 14 mm distal to the cranial aspect of the iliac crest in males and females, respectively. Not only is the gluteal pillar smaller than previously thought, in 41% of males and 73% of females, it is not be large enough for 5 mm implants. CONCLUSION: This study quantitatively assesses the dimensions of the IOTC, the iliac crest osseous corridor, and the gluteal pillar. Overall, our findings provide improved understanding of the limits for implant use in the iliac wing as well as better appreciation of the complex osteology of the ilium. This will help surgeons to identify safe areas for implant placement and avoid inadvertent cortical penetration.

Defining the iliac wing osseous fixation pathways: anatomy and implant constriction points.

INTRODUCTION: Insertion of iliac wing implants requires understanding of the curvilinear shape of the ilium. This study serves to quantitatively identify the area of iliac inner-outer table convergence (IOTC), characterize the iliac wing osseous corridor, and define the gluteal pillar osseous corridor. METHODS: Computed tomography scans of 100 male and 100 female hemipelves were evaluated. The iliac wing was studied using manual best-fit analysis of the bounds of the inner and outer cortices. The IOTC was defined as the location of the iliac wing with an intercortical width less than 5 mm. The shortest distance from the apex of the iliac crest to the superior border of the IOTC was defined as the iliac wing osseous corridor. Finally, the width of the gluteal pillar corridor from the gluteus medius tubercle to the ischial tuberosity was measured. RESULTS: The IOTC is an elliptical area measuring 22.3 cm2. All ilia had an area where the inner and outer cortices converged to an intercortical width of less than 5 mm; 48% converged to a single cortex. The shortest mean distance from the superior edge of the iliac crest to the beginning of the IOTC was 20.3 mm in men and 13.8 mm in women (p < 0.001). The gluteal pillar diameter averaged 5.3 mm in men and 4.3 mm in women (p < 0.001). DISCUSSION: All ilia converge to a thin and frequently unicortical central region. A 4.5 mm iliac wing lag screw will not breach the cortex if it remains within 20 mm or 14 mm distal to the cranial aspect of the iliac crest in males and females, respectively. Not only is the gluteal pillar smaller than previously thought, in 41% of males and 73% of females, it is not be large enough for 5 mm implants. CONCLUSION: This study quantitatively assesses the dimensions of the IOTC, the iliac crest osseous corridor, and the gluteal pillar. Overall, our findings provide improved understanding of the limits for implant use in the iliac wing as well as better appreciation of the complex osteology of the ilium. This will help surgeons to identify safe areas for implant placement and avoid inadvertent cortical penetration.

Supraacetabular osseous corridor: defining dimensions, sex differences, and alternatives.

INTRODUCTION: The supraacetabular (SA) corridor extends from the anterior inferior iliac spine to the posterior ilium and can safely accommodate implants to stabilize pelvic and acetabular fractures. However, quantitative analysis of its dimensions and characteristics have not been thoroughly described. This study seeks to define the dimensions, common constriction points, and any alternative trajectories that would maximize the corridor diameter. METHODS: Computed tomography of 100 male and 100 female hemipelves without osseous trauma were evaluated. The corridor boundaries were determined through manual best-fit analysis. The largest intercortical cylinder within the pathway was created and measured. Alternative trajectories were tested within the SA boundaries to identify another orientation that maximized the diameter of the intercortical cylinder. RESULTS: The traditional SA corridor had a mean diameter of 8.3 mm in men and 6.2 mm in women. This difference in diameter is due to a more S-shaped ilium in women. A larger alternative SA corridor was found that had a less limited path through the ilium and measured 11.3 mm in men and 9.9 mm in women. These dimensions are significantly different compared to those of the traditional SA corridor in both men and women. CONCLUSIONS: In men, the SA corridor allows for the safe passage of most hardware used in pelvic and acetabular fractures. However, in women, the SA corridor is restricted by a more S-shaped ilium. An alternative trajectory was found that has a significantly larger mean diameter in both sexes. Ultimately, the trajectory of hardware will be dictated by the clinical scenario. When large implants are needed, especially in women, we recommend considering the alternative SA corridor.

MRI-only occult geriatric hip fractures: is displacement common with nonoperative treatment?

INTRODUCTION: Although surgical fixation is routinely recommended for geriatric hip fractures, nonoperative treatment may be an option for certain stable fracture patterns. Occult hip fractures are nondisplaced fractures not evident on radiographs, but display intraosseous edema on MRI. Our aim is to report the rate of nonoperative treatment failure in patients with occult geriatric hip fractures. METHODS: All nonoperatively treated femoral neck or intertrochanteric femur fractures (AO/OTA 31A and 31B) from 2003 to 2018 were identified. Patients older than 65 years with negative radiographs but a hip fracture evident on MRI were included. Patients who died prior to fracture displacement or union were excluded. Charts and imaging were reviewed for demographic data, fracture type, clinical course, displacement, and whether corrective surgery was performed. RESULTS: Of 15 final study patients, there were 6 femoral neck and 9 intertrochanteric fractures. Two fractures displaced, both requiring surgery (2/15; 13.3%). Both displacements occurred in the femoral neck group (2/6; 33%) compared to none in the intertrochanteric cohort (0/9; 0%). This trend did not reach statistical significance (p = 0.14). CONCLUSION: Thirty-three percent (2/6, 33%) of femoral neck fractures displaced and required surgery. The remainder of the cohort (13/15, 87%) healed without complication, including all of the intertrochanteric fractures (9/9, 100%). Although this difference did not reach statistical significance, the results may better inform treatment discussions for geriatric patients with occult hip fractures diagnosed by MRI. LEVEL OF EVIDENCE: Level III.

The Intermalleolar Method for Intraoperative Rotational Assessment of the Tibia-A Prospective Clinical Validation Study.

OBJECTIVES: To determine the accuracy of the intermalleolar method, an intraoperative fluoroscopic method for assessing tibial rotation in patients undergoing intramedullary nail fixation for tibial shaft fractures, by comparing it with the gold standard computed tomography (CT). DESIGN: Prospective cohort study. SETTING: Academic Level 1 trauma center. PATIENT SELECTION CRITERIA: Consecutive patients, aged 18 years and older, with unilateral tibial shaft fractures who underwent intramedullary fixation from September 2021 to January 2023. OUTCOME MEASURES AND COMPARISONS: Intraoperatively, tibial rotation measurements were obtained using the intermalleolar method on both the uninjured and injured limbs. Postoperatively, patients underwent bilateral low-dose lower extremity rotational CT scans. CT measurements were made by 4 blinded observers. Mean absolute rotational differences and standard errors were calculated to compare the injured and uninjured limbs. Subgroup analysis was performed assessing accuracy relating to injured versus uninjured limbs, body mass index, OTA/AO fracture pattern, tibial and fibular fracture location, and distal articular fracture extension requiring fixation. RESULTS: Of the 20 tibia fractures, the mean patient age was 43.4 years. The intermalleolar method had a mean absolute rotational difference of 5.1 degrees (standard error 0.6, range 0-13.7) compared with CT. Sixty percent (24/40) of the measurements were within 5 degrees, 90% (36/40) of the measurements were within 10 degrees, and 100% (40/40) were within 15 degrees of the CT. No patients were revised for malrotation postoperatively. CONCLUSIONS: The intermalleolar method is accurate and consistently provides intraoperative tibial rotation measurements within 10 degrees of the mean CT measurement for adult patients undergoing intramedullary nail fixation for unilateral tibial shaft fractures. This method may be employed in the operating room to accurately quantify tibial rotation and assist with intraoperative rotational corrections. LEVEL OF EVIDENCE: Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Management of Obturator Vessel Hemorrhage by Pubic Ramus Osteotomy During Acetabular Fixation-A Technical Trick.

SUMMARY: It is known that hemorrhage from pelvic ring and acetabular fractures can cause hemodynamic instability. Methods to improve visualization and thus management of bleeding vessels are not commonly described. This report highlights techniques to manage hemorrhage from a retracted obturator vein during the definitive fixation of a complex acetabular fracture. After uncomplicated modified Stoppa anterior intrapelvic approach, abrupt and profuse bleeding was encountered from the distal end of a lacerated obturator vein, which had retracted into the obturator foramen. With unsuccessful attempts to achieve hemostasis, a superior pubic osteotomy was performed which allowed excellent visualization of the bleeding vein and ligation. It must be emphasized that the surgeon attempted all these other measures before performing an osteotomy. This technical trick contributes to the overall knowledge as a means of achieving emergent hemostasis associated with distal obturator vessel hemorrhage, a well described risk in complex acetabular fractures.

Joint and long-bone gunshot injuries.

Gunshot wounds remain a major clinical problem, with the number of nonfatal gunshot wounds reported as 60,000 to 80,000 per year in the United States. Bone or joint injuries comprise a major portion of gunshot wound injuries. It is paramount for orthopaedic surgeons to be thorough in their treatment of patients with these injuries. Intra-articular injuries remain a source of significant clinical morbidity because of joint stiffness, arthritis, and the risk of infection. Treatment of long-bone fractures is a challenging clinical problem, and further studies are needed to investigate modern treatment methods. Lead toxicity is a potential risk for patients with gunshot injuries, particular for those with joint injuries. The clinician's recognition of the signs and symptoms of lead toxicity is important to achieve the best care for these patients.

Nonoperative Geriatric Hip Fracture Treatment Is Associated With Increased Mortality: A Matched Cohort Study.

OBJECTIVE: To report the mortality data and life expectancy of geriatric hip fracture patients who underwent nonoperative management and compare that with a matched operative cohort. DESIGN: Retrospective cohort study. SETTING: Level 1 trauma center. PATIENTS: Geriatric (65 years of age and older) femoral neck or intertrochanteric fracture (OTA/AO 31A and 31B) patients. INTERVENTION: Operative treatment with either arthroplasty, cannulated screws, sliding hip screw device, or cephalomedullary nail compared with nonoperative cohort. MAIN OUTCOME MEASUREMENTS: In-hospital, 30-day, and 1-year mortality. RESULTS: Two hundred thirty-one patients, comprising 154 operative and 77 nonoperative patients, were compared. There were no significant differences among age, sex, fracture location, Charlson Comorbidity Index, preinjury living location, dementia, and history of cardiac arrhythmia between the 2 cohorts. Nonoperatively managed patients were found to have a significantly higher percent in-hospital (28.6 vs. 3.9; P < 0.0001), 30-day (63.6 vs. 11.0; <0.0001), and 1-year (84.4 vs. 36.4; P < 0.0001) mortality. The mean life expectancy after a hip fracture for the nonoperative cohort was significantly shorter than the operative group (221 vs. 1024 days; P < 0.0001). CONCLUSIONS: Nonoperatively treated hip fracture patients had an 84.4% 1-year mortality that was significantly higher than a matched operative cohort. Our results demonstrate the bleak overall prognosis for nonoperatively treated geriatric hip fractures as well as the associated reduction in mortality with surgical treatment. Our findings offer helpful information by providing updated mortality data when discussing nonoperative hip fracture management with patients and their family. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Early changes in prostaglandins precede bone formation in a rabbit model of heterotopic ossification.

We have tested the hypothesis that the formation of heterotopic ossification (HO) in a rabbit model is correlated with a local increase in specific prostaglandins that may modulate mechanisms of ossification. Rabbits were sacrificed at 1 to 21 days following the daily forcible flexion of immobilized knees. The extraction and analysis of prostaglandins (PG) E2, F2alpha, D2, 6-keto-F1alpha, and thromboxane B2 in vastus intermedius muscles of manipulated legs revealed increases compared to control hindlimbs for all five prostaglandins, albeit of differing magnitude. The earliest increase was observed for PGF2alpha after 24 h (to 2.6-fold of control) with peak levels observed at day ten (185-fold of control). PGE2 was increased above control from 2 to 21 days following manipulation, with a peak level of 33-fold of control after 10 days. In a separate arm of the study, the role of PGE2 was investigated through the use of pharmacological antagonist of the PGE2 receptors and one of its second messengers, cAMP. Rabbits were preadministered the PGE2/PGD receptor antagonist AH 6809 or the cAMP antagonist Rp-cAMP prior to undergoing the regimen of limb immobilization and passive exercise. Both AH 6809 and Rp-cAMP were found to prevent the later development of radiographically documented heterotopic ossification in 15 out of 16 animals, thus identifying prostaglandins as being required for the development of ectopic bone. In this latter group, all but one pharmacologically treated animal showed an absence of HO at 3, 4, 5, or 6 weeks. These findings suggest an obligate cascade of prostaglandins for HO that offers the potential for novel prophylactic therapies, including those that target receptors for specific prostaglandins.

Surgical Site Infections in Patients With Type 3 Open Fractures: Comparing Antibiotic Prophylaxis With Cefazolin Plus Gentamicin Versus Piperacillin/Tazobactam.

OBJECTIVES: The purpose of this study was to compare rates of surgical site infection (SSI) in patients with type 3 open fractures who had received cefazolin plus gentamicin versus piperacillin/tazobactam for antibiotic prophylaxis. DESIGN: Retrospective cohort study. SETTING: Level 1 trauma center. PATIENTS: Seven hundred sixty-six patients admitted between January 1, 2004, and December 31, 2012, with open fractures were identified using the National Trauma Data Bank by searching International Classification of Diseases, Ninth Revision (ICD-9) codes. Electronic medical record review revealed 134 patients with type 3 open fractures, of which 72 were included in the final analysis. INTERVENTION: Administration of cefazolin plus gentamicin or piperacillin/tazobactam for type 3 open fracture antibiotic prophylaxis. MAIN OUTCOME MEASUREMENTS: SSI, nonunion, death, and rehospitalization rates at 1 year. RESULTS: Surgical site infection at 1 year occurred in 12 of 37 patients (32.4%) in the cefazolin plus gentamicin group and 11 of 35 patients (31.4%) in the piperacillin/tazobactam group (P = 1.000). Nonunion, death, and rehospitalization rates at 1 year were similar between the 2 groups. Although there was no statistically significant difference in SSI at 30 days between groups, the rate was higher in the cefazolin plus gentamicin group (21.6% vs. 11.4%; P = 0.246). CONCLUSIONS: At our institution, use of piperacillin/tazobactam as compared with cefazolin plus gentamicin for antibiotic prophylaxis in patients with type 3 open fractures showed similar rates of SSI, nonunion, mortality, and rehospitalization at 1 year after injury. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

A three-dimensional comparison of intramedullary nail constructs for osteopenic supracondylar femur fractures.

OBJECTIVES: This study developed a new 6 degree-of-freedom, unconstrained biomechanical model that replicated the in vivo loading environment of femoral fractures. The objective of this study was to determine whether various distal fixation strategies alter failure mechanisms and/or offer mechanical advantages when performing retrograde intramedullary nail (IMN) stabilization of supracondylar femur fractures in osteoporotic bone. METHODS: Forty fresh-frozen human femora were allocated into 2 groups of matched pairs: "locked" (fixed angle locking construct with both distal locking screws rigidly attached to the IMN) versus "unlocked" (conventional locking technique with 2 distal locking screws targeted through the distal locking screw holes of the IMN) and "locked" versus "washer" (fixed angle locking with the most distal screw exchanged for a bolt with condyle washers) distal fixation of a retrograde IM nails. A comminuted fracture (OTA 33-A3) was simulated with a wedge osteotomy. Bone density measurements were completed on all specimens before instrumentation. Instrumented femurs were loaded axially to failure, whereas 6 degree-of-freedom translations and angulations were measured using Roentgen stereophotogrammetric analysis. RESULTS: Mean (± SD) load born by "locked" specimens (1609 ± 667 N) at clinical failure was 38.1% greater (P = 0.09) than the corresponding mean load born by "unlocked" specimens (1165 ± 772 N). Clinical failure for the "washer" group (1738 ± 772 N) was 29.9% greater (P = 0.07) than the corresponding mean of the "locked" counterparts (1338 ± 822 N). Failure load was most clearly related to bone density in the "unlocked" fixation group. CONCLUSIONS: Predicting failure load based on bone density using a least squares estimate suggests that the washer construct provides superior fixation to other treatment techniques. The failure mechanism for a comminuted, supracondylar fracture cannot be analyzed accurately with a 1-dimensional measurement. The most common failure mechanism in this model was medial translation and varus angulation.

Compliance with the Eastern Association for the Surgery of Trauma guidelines for prophylactic antibiotics after open extremity fracture.

CONTEXT: Prophylactic antibiotics, paired with wound care and surgical intervention, is considered the standard of care for patients with open fracture. Guidelines from the Eastern Association for the Surgery of Trauma (EAST) recommend specific prophylactic antimicrobial therapy based on the type of open fracture. AIMS: We quantified adherence to EAST guideline recommendations and documented the incidence of infection in patients with open fracture. SETTINGS AND DESIGN: A retrospective, observational study of all patients with open fracture admitted to our facility from January 2004 to December 2008 was conducted. MATERIALS AND METHODS: Patients were divided into compliant and noncompliant groups according to the EAST guideline recommendations. Compliance was defined as an appropriate spectrum of therapy for guideline suggested duration. We assessed for surgical and non-surgical site infections, and morbidity outcomes. STATISTICAL ANALYSIS: Nominal data were explored using summary measures. Continuous variables were compared using the Student t-test or the Mann-Whitney U-test. Dichotomous data were compared using χ(2) statistic or Fisher's exact test. RESULTS: The final analysis included 214 patients. Prophylactic antibiotics were guideline compliant in 28.5% of patients, and ranged from 10.0% in type 3b fractures to 52.7% in type 1 fractures. The most common reason for non-compliance was the use of guideline recommended coverage that exceeded the suggested duration (71.2%). Patients who received non-compliant therapy required prolonged hospital lengths of stay (6 vs. 3 days, P = 0.0001). The overall incidence of infection was similar regardless of guideline compliance (17.0% vs. 11.5%, P = 0.313). CONCLUSIONS: Prophylactic antibiotics for open fracture frequently exceeded guideline recommendations in duration and spectrum of coverage, especially in more severe fracture types. Non-compliance with EAST recommendations was associated with increased in-hospital morbidity.

Clinical update: gunshot wound ballistics.

Although firearm related injury and mortality actually may be declining, gunshot trauma remains a significant cause of morbidity and socioeconomic cost with 115,000 missile injuries annually and as many as 40,000 deaths. Wounds typically are classified as low-velocity (< 2000 feet/second) or high-velocity (> 2000 feet/second). However, these terms can be misleading. More important is the efficiency of energy transfer, which is dependent on the projectile's physical characteristics including deformation and fragmentation, kinetic energy, stability, entrance profile, path traveled through the body, and the biologic characteristics of the tissues. Therefore, the decision whether to explore the wound should not be based solely on the involvement of a high-velocity or low-velocity weapon. The majority of low-velocity gunshot wounds can be treated safely nonoperatively with local wound care and outpatient treatment. Treatment of associated fractures generally is dictated by the bony injuries, which have similar personalities to closed fractures. Because contamination is not always apparent, routine antibiotic prophylaxis still is recommended. The soft tissues assume a more crucial role in high-velocity and shotgun fractures, whereas high-energy injuries and grossly contaminated wounds mandate irrigation, appropriate debridement, and the use of open fracture protocols. However, a patient with a high-velocity wound with limited soft tissue disruption, no significant functional deficits, no evidence of bullet fragmentation, and minimal bony involvement can be a candidate for simple wound care. When exploration is indicated, decompression and excision of necrotic tissue is the rule with color, consistency, contractility, and capacity to bleed providing valuable information regarding muscle viability.