Closed reduction and internal fixation for tillaux fractures, based on pre-operative three-dimensional computed tomography.

OBJECTIVE: This study aimed to propose treatment protocol and identify patterns of tillaux fractures using three-dimensional (3D) computed tomography (CT) analysis and to describe an effective reduction technique. METHODS: Forty-two juvenile patients with tillaux fractures were evaluated with 3D-CT scan for fracture displacement pattern and received surgical treatment. Tillaux fragment was reduced by pushing the superomedial quadrant part of the fragment slightly downward towards the ankle joint from anterolateral to posteromedial through 5-mm skin incisions with mosquito forceps. A 4.0 cannulated screw was subsequently inserted from the anterolateral to the posteromedial side parallel to the ankle joint. We analysed the distance and direction of fracture displacement with 3D-CT before the surgery. Pre-operative and post-operative plain radiographs were evaluated. RESULTS: Pre-operative 3D-CT analysis revealed a common fracture pattern, varus tilt, and external rotation of fragment. We achieved satisfactory reduction with residual fracture gaps less than 2 mm in 42 cases. Two cases had a 13-mm anterior gap that was reduced by mini-open reduction because of periosteal impingement. No significant clinical complications were found. CONCLUSION: The closed reduction technique developed based on the fracture pattern identified by 3D-CT anatomical analysis is safe and effective in treating tillaux fractures.

Evaluation of Intramedullary Olecranon Screw Fixation for Simple Olecranon Fractures: A Biomechanical Study.

PURPOSE: The purpose of this study was to biomechanically evaluate the stability of the 6.5 mm intramedullary (IM) olecranon screw compared to locking compression plate fixation for Orthopedic Trauma Association/AO Foundation (OTA/AO) 2U1B1 olecranon fractures under cyclic range of motion of the elbow. METHODS: Twenty paired elbows were randomized to either IM olecranon screw or locking compression plate fixation of a simulated OTA/AO 2U1B1 fracture. Pullout strength was tested by increasing force applied to the triceps and proximal fragment. Fracture gap displacement was measured using differential variable reluctance transducers as the elbow was cycled through a 135° arc of motion using a servohydraulic testing system. RESULTS: Analysis of variance revealed significant interaction between group and load on fracture distraction after the 500th cycle in three settings: between the plate at 5-pound load and screw at 35-pound load, the screw at 5-pound load and screw at 35-pound load, and between the plate at 15-pound load and screw at 35-pound load. The difference in the rate of failure between plate (2 of 80 samples) and screw (4 of 80 samples) was not statistically significant. CONCLUSIONS: For OTA/AO 2U1B1 olecranon fractures, a single 6.5 mm IM olecranon screw demonstrated similar stability when compared to the locking compression plates throughout range of motion testing. CLINICAL RELEVANCE: From a biomechanical perspective, 6.5 mm IM screws and locking compression plates have similar ability to maintain fracture reduction following simulated elbow range of motion exercises in OTA/AO 2U1B1 fractures, giving surgeons another option in the management of these fractures.

Impact of aberrant beam paths on antero-posterior shoulder radiographs in proximal humeral fractures.

INTRODUCTION: Accurate radiographic assessment of proximal humeral fractures (PHF) is important as it influences clinical decision-making and predicts clinical outcome. Since aberrant radiographic views might influence the assessment of fracture displacement, it was the goal of this study to investigate the impact of aberrant beam paths on radiographic assessment of PHF. MATERIALS AND METHODS: Ten consecutive patients with a displaced PHF, bilateral computed tomography (CT) scan, and a true clinical AP radiograph were included. Digitally reconstructed radiographs (DRRs) were generated and aberrant beam paths were simulated by rotation of ± 30° around the horizontal (flexion and extension) and vertical axis (internal and external rotation) by increments of 10°. Measurement of the neck-shaft-angle (NSA) and eccentric head index (EHI) addressed humeral angulation and offset, respectively. Paired comparisons determined the influence of aberrant beam paths on both measurements between incremental altered views, and between clinical and digital true AP views. Descriptive statistics assessed the change in Neer classification and recommended treatment. RESULTS: True AP DRRs approximated the clinical true AP view by a mean difference of 2° for NSA, and a mean difference of 0.12 for EHI. NSA in injured shoulders was most susceptible to malrotation around the vertical axis (p < 0.03), with largest differences seen for internal rotation. Aberrant projections in extension had no influence on NSA (p > 0.70), whereas flexion of ≥ 20° and 30° demonstrated differences in injured and uninjured shoulders, respectively (p < 0.05). EHI was only influenced by malrotation in internal rotation in uninjured shoulders (p < 0.03). Alterations in Neer type occurred at 30° of malrotation in 5 cases, with a change in recommended treatment in 2. CONCLUSIONS: Humeral angulation and offset measurements on AP radiographs are more susceptible to aberrant beam paths in fractured humeri. Altered radiographic beam paths around the vertical axis showed the most substantial influence on the assessment of PHF, with angular measurements demonstrating larger differences then offset measurements. Beam path alterations of 30° can influence the Neer classification, and might influence fracture displacement-based decisions.

The CAST study protocol: a cluster randomized trial assessing the effect of circumferential casting versus plaster splinting on fracture redisplacement in reduced distal radius fractures in adults.

BACKGROUND: There is no consensus concerning the optimal casting technique for displaced distal radius fractures (DRFs) following closed reduction. This study evaluates whether a splint or a circumferential cast is most optimal to prevent fracture redisplacement in adult patients with a reduced DRF. Additionally, the cost-effectiveness of both cast types will be calculated. METHODS/DESIGN: This multicenter cluster randomized controlled trial will compare initial immobilization with a circumferential below-elbow cast versus a below-elbow plaster splint in reduced DRFs. Randomization will take place on hospital-level (cluster, n = 10) with a cross-over point halfway the inclusion of the needed number of patients per hospital. Inclusion criteria comprise adult patients (≥ 18 years) with a primary displaced DRF which is treated conservatively after closed reduction. Multiple trauma patients (Injury Severity Score ≥ 16), concomitant ulnar fractures (except styloid process fractures) and patients with concomitant injury on the ipsilateral arm or inability to complete study forms will be excluded. Primary study outcome is fracture redisplacement of the initial reduced DRF. Secondary outcomes are patient-reported outcomes assessed with the Disability Arm Shoulder Hand score (DASH) and Patient-Rated Wrist Evaluation score (PRWE), comfort of the cast, quality of life assessed with the EQ-5D-5L questionnaire, analgesics use, cost-effectiveness and (serious) adverse events occurence. In total, 560 patients will be included and followed for 1 year. The estimated time required for inclusion will be 18 months. DISCUSSION: The CAST study will provide evidence whether the type of cast immobilization is of influence on fracture redisplacement in distal radius fractures. Extensive follow-up during one year concerning radiographic, functional and patient reported outcomes will give a broad view on DRF recovery. TRIAL REGISTRATION: Registered in the Dutch Trial Registry on January 14th 2020. Registration number: NL8311 .

Association of secondary displacement of distal radius fractures with cortical bone quality at the distal radius.

INTRODUCTION: The aim of this study was to investigate the associations of patient characteristics, bone mineral density (BMD), bone microarchitecture and calculated bone strength with secondary displacement of a DRF based on radiographic alignment parameters. MATERIALS AND METHODS: Dorsal angulation, radial inclination and ulnar variance were assessed on conventional radiographs of a cohort of 251 patients, 38 men and 213 women, to determine the anatomic position of the DRF at presentation (primary position) and during follow-up. Secondary fracture displacement was assessed in the non-operatively treated patients (N = 154) with an acceptable position, preceded (N = 97) or not preceded (N = 57) by primary reduction (baseline position). Additionally, bone microarchitecture and calculated bone strength at the contralateral distal radius and tibia were assessed by HR-pQCT in a subset of, respectively, 63 and 71 patients. OUTCOME: Characteristics of patients with and without secondary fracture displacement did not differ. In the model with adjustment for primary reduction [OR 22.00 (2.27-212.86), p = 0.008], total [OR 0.16 (95% CI 0.04-0.68), p = 0.013] and cortical [OR 0.19 (95% CI 0.05-0.80], p = 0.024] volumetric BMD (vBMD) and cortical thickness [OR 0.13 (95% CI 0.02-0.74), p = 0.021] at the distal radius were associated with secondary DRF displacement. No associations were found for other patient characteristics, such as age gender, BMD or prevalent vertebral fractures. CONCLUSIONS: In conclusion, our study indicates that besides primary reduction, cortical bone quality may be important for the risk of secondary displacement of DRFs.

Pelvic Ring Fractures: A Biomechanical Comparison of Sacral and Lumbopelvic Fixation Techniques.

BACKGROUND CONTEXT: Pelvic ring fractures are becoming more common in the aging population and can prove to be fatal, having mortality rates between 10% and 16%. Stabilization of these fractures is challenging and often require immediate internal fixation. Therefore, it is necessary to have a biomechanical understanding of the different fixation techniques for pelvic ring fractures. METHODS: A previously validated three-dimensional finite element model of the lumbar spine, pelvis, and femur was used for this study. A unilateral pelvic ring fracture was simulated by resecting the left side of the sacrum and pelvis. Five different fixation techniques were used to stabilize the fracture. A compressive follower load and pure moment was applied to compare different biomechanical parameters including range of motion (contralateral sacroiliac joint, L1-S1 segment, L5-S1 segment), and stresses (L5-S1 nucleus stresses, instrument stresses) between different fixation techniques. RESULTS: Trans-iliac-trans-sacral screw fixation at S1 and S2 showed the highest stabilization for horizontal and vertical displacement at the sacral fracture site and reduction of contralateral sacroiliac joint for bending and flexion range of motion by 165% and 121%, respectively. DTSF (Double transiliac rod and screw fixation) model showed highest stabilization in horizontal displacement at the pubic rami fracture site, while the L5_PF_W_CC (L5-Ilium posterior screw fixation with cross connectors) and L5_PF_WO_CC (L5-Ilium posterior screw fixation without cross connectors) showed higher rod stresses, reduced L1-S1 (approximately 28%), and L5-S1 (approximately 90%) range of motion. CONCLUSIONS: Longer sacral screw fixations were superior in stabilizing sacral and contralateral sacroiliac joint range of motion. Lumbopelvic fixations displayed a higher degree of stabilization in the horizontal displacement compared to vertical displacement of pubic rami fracture, while also indicating the highest rod stresses. When determining the surgical approach for pelvic ring fractures, patient-specific factors should be accounted for to weigh the advantages and disadvantages for each technique.

Is three-point fixation needed to mechanically stabilize zygomaticomaxillary complex fractures?

Fixation is critical in zygomaticomaxillary complex (ZMC) fractures to avoid malunion; however, controversy exists as to how much hardware is required to achieve adequate stability. Current fixation regimens may not represent the minimum stabilization needed for uneventful healing. Craniomaxillofacial (CMF) computational models have shown limited load transmission through the infraorbital rim (IOR), and a previous experimental study of ZMC fractures has suggested that IOR plating does not alter CMF bone strain patterns. This study aimed to measure the impact of stabilization on fracture site displacement under muscle loading, testing the hypothesis that three-point fixation is not critical for ZMC fracture stability. Four ZMC complex fractures were simulated on two cadaveric samples and stabilized with three-point plating. Displacements simulating mouth openings of 20 mm and 30 mm were applied to the mandible using a custom apparatus. Fracture gap displacement under load was measured at multiple points along each fracture line, and bone strain was captured using a combination of uniaxial and rosette gauges. Data capture was repeated with the IOR plate removed (two-point fixation) and with the zygomaticomaxillary plate removed (one-point fixation). Fracture displacement under muscle loading was consistent, with gaps of less than 1 mm in 95% of cases (range 0.05-1.44 mm), reflecting clinical stability. Large variabilities were observed in the strain measurements, which may reflect the complexity of CMFS load patterns and the sensitivity of strain values to gauge placement. This study supports the concept of hardware reduction, suggesting that two-point (or even one-point) fixation may provide sufficient stability for a ZMC fracture under applied muscle loading.

Varus mal-alignment and residual displacement are associated with delayed union in subtrochanteric femur fracture- A retrospective observational study.

Background: Subtrochanteric femoral (ST) fractures are associated with high rates of delayed and non-union. The aim of this study was to analyse the risk factors associated with delayed/non-union in ST fractures. Methods: All patients with surgical stabilisation of ST fractures during the period 2014 to 2019 were identified in an electronic patient records database in two trauma centres. Exclusion criteria were incomplete clinical/radiological data, pathological fractures and loss to follow-up. Radiographs at about 6 months post-surgery were assessed for fracture union using Radiographic Union Score for Hip (RUSH). Fracture was deemed to be un-united if RUSH score was <18. CCD (caput-collum-diaphyseal) angle of operated and uninjured hip, residual displacement at fracture site and 3-point relationship was calculated on operative or immediate post-operative images in both groups. Student's t-test was used to compare CCD angle difference between operated and uninjured sides and the residual fracture displacement between delayed union and united fractures group. Chi-square test was used for 3-point relationship. Observational analysis was performed on implant failure rates including distal screw breakage. Results: During the study period, there were total of 278 patients. 193 with inadequate data and 22 with pathological fractures were excluded. Advanced age and female sex had significantly higher rate of delayed union (p value of 0.043 and 0.003 respectively). Delayed union group (26) had a mean RUSH score of 14.1 and united group (37) had a mean RUSH score of 26.3 (p = 0.019). The mean CCD angle difference between operated and uninjured sides was -5.77° for delayed union and -2.33° for united fractures (p = 0.03). Residual displacement at fracture site showed statistically significant difference between delayed union and united fractures on anteroposterior and lateral views (p = 0.001 each). There was no statistical difference in 3-point relationship of implant in two groups (p = 0.775). 10 revision procedures were performed for implant failures. Distal screw failure (3 cases) was not a precursor for non-union in this study. Conclusion: This study confirms varus alignment of hip and residual fracture displacement after fracture fixation of subtrochanteric fracture are surgeon associated significant risk factors for delayed union at 6 months. Fracture contact and alignment are key to reduce failures in these group of fractures. Among patient factors, advancing age and female sex predisposes to higher rate of delayed union.

Inverse association between sarcopenia and displacement in the early phase of fragility fractures of the pelvis.

Objectives: Fragility fractures of the pelvis (FFP) commonly occur in the frail elderly. Displacement in the posterior pelvic ring is recognized as the key sign of instability. This study aims to elucidate the relationship between computer tomography (CT)-based frailty markers and displacement of the posterior pelvic ring within 7 days after injury. Methods: This retrospective study included 49 patients (42 females, 7 males) with FFP (type I 10, type II 24, type III 12, type IV 3). On a CT slice at the level of the third lumbar vertebra, skeletal muscle area, skeletal muscle radiation attenuation, and skeletal muscle index (SMI) were calculated as sarcopenia markers. Osteopenia was measured with trabecular region of interest attenuation technique on the same CT slice. Results: There was no difference in the demographics between non-displaced and displaced FFP. CT-based data showed that patients with FFP had osteopenia. However, no difference was found between non-displaced and displaced FFP. SMI was higher in FFP types III/IV than non-displaced FFP when CT-based data on sarcopenia were compared among all patients. Female patients with FFP demonstrated similar results. Logistic regression analysis using the demographics and CT-based markers on sarcopenia and osteopenia revealed that SMI was a potential determinant of displacement of the posterior pelvic ring fractures. Conclusions: There was inverse association between sarcopenia and displacement of the posterior pelvic ring in the early phase of FFP. Relatively preserved muscle may develop displacement in the elderly with osteopenia.

Percutaneous bone adhesive application for Jones fracture "at-risk" of nonunion or delayed union: a hypothesis.

BACKGROUND: Bone adhesives have been on the forefront of orthopedic surgery research for decades due to the potential benefit they may have in fracture management. Current publications and research being conducted on bone adhesive could be applied to our current hypothesis for the benefit of a novel minimally invasive treatment option for a select cohort of fractures, Jones fractures. The select fracture's gold standard of treatment would be nonoperative, but with risk of complications including nonunion and delayed union. PRESENTATION OF HYPOTHESIS: We hypothesize that percutaneous application of bone adhesive will provide an additional treatment option for fracture patterns that do not require operative fixation, but would benefit from additional stability. The primary outcome measures would be (1) duration of time required for bony consolidation (defined as 3 of 4 bridging cortices) and (2) duration of absenteeism (inability to work), and pain levels within the first week after the procedure. Secondary outcome measures would be the incidence of nonunion or delayed union. We hypothesize that the select bone adhesive would accelerate bony consolidation, decrease absenteeism, decrease pain levels within the first week after procedure, and decrease the incidence of delayed union and/or nonunion. TESTING OF HYPOTHESIS: We propose a prospective multicenter, randomized, and open label trial clinical trial to test the bone adhesive via percutaneous injection into acute non-displaced or minimally displaced Jones fractures. IMPLICATIONS OF HYPOTHESIS: Bone adhesives are a new frontier in treatment of fractures, currently in laboratory and animal testing phases. The appropriate bone adhesive formula has not been approved for clinical trial use, but the implications of the bone adhesive may go beyond decreased complications and ease of stabilizing a select cohort of closed fractures. With the injectable compound illustrated (Fig. 1), the adhesive could be applied percutaneously in hopes of achieving improved outcomes compared to non-operative treatment. The overall goal of the clinical trial is to provide patients a safe treatment option for improved bone union rates of nonoperative fractures compared to the current gold standard management of the same fracture with earlier pain control, early bony consolidation and lower risk of delayed union/nonunion. The ideal patient population for use of a percutaneous bone adhesive in future studies would be for those with multiple medical comorbidities for whom surgical risks outweigh the benefits, in addition to patients at high risk for nonunion based on fracture pattern or systemic biology.

Role of preoperative posterior tilt on the outcomes of internal fixation of non-displaced femoral neck fractures: A systematic review and meta-analysis.

INTRODUCTION: There has been an increased interest in the role of preoperative posterior tilt, as measured on lateral radiographs, on the outcomes of internal fixation of non-displaced femoral neck fractures (FNF). The goal was to assess the available evidence for this in the literature. PATIENTS AND METHODS: PRISMA guidelines were followed. PubMed, Embase and Cochrane were searched on June 10th, 2020 for studies assessing the role of posterior tilt on outcomes of internal fixation of non-displaced FNF. Primary outcomes were non-union and fixation failure, avascular necrosis (AVN), treatment failure, and reoperation (excluding symptomatic hardware removal). Outcomes were reported in Odds Ratio (OR) with 95% confidence intervals [CI]. RESULTS: Fourteen studies and 3729 patients were included (mean age 76 years, 72% female, mean follow-up 25 months). Moderate evidence was noted for the following: patients with greater preoperative posterior tilt had an increased risk of non-union and fixation failure (OR 2.4 [1.3 - 4.3]; p = 0.006), no increased risk of AVN (p = 0.550), an increased risk of treatment failure (OR 6.0 [2.2 - 15.9]; p<0.001) and reoperation (OR 2.5 [1.4 - 4.4]; p = 0.002). Furthermore, a greater preoperative tilt of 9.0° [4.1° - 13.9°] for treatment failure and 6.1° [3.7° - 8.5°] (p<0.001) for reoperation were noted in the unsuccessfully treated groups when compared to the successfully treated groups. Four studies found a threshold for posterior tilt ranging from 7° to 20° CONCLUSION: There is moderate evidence that patients with non-displaced FNF and greater tilt have an increased risk of unsuccessful outcomes following internal fixation. Older patients with a preoperative tilt of ≥20° might benefit from arthroplasty surgery, although studies assessing the optimal threshold are needed.

Can preoperative radiographs predict hardware complication or fracture displacement after operative treatment of pelvic ring injuries?

INTRODUCTION: Operative fixation of pelvic ring injuries is associated with a high risk of hardware failure and loss of reduction. The purpose of this study was to determine whether preoperative radiographs can predict failure after operative treatment of pelvic ring injuries and if the method of fixation effects their risk. PATIENTS AND METHODS: We conducted a retrospective cohort study of 143 patients with pelvic ring injuries treated with operative fixation at a level 1 trauma center. Preoperative radiographs were examined for the presence of the following characteristics: bilateral rami fractures, segmental or comminuted rami fractures, contralateral anterior and posterior injuries, complete sacral fracture, and displaced inferior ramus fractures. The method of fixation was classified based on the presence of anterior, posterior, or combined anterior and posterior fixation as well as whether or not posterior fixation was performed at a single or multiple sacral levels. Post-operative radiographs were examined for hardware failure or loss of reduction. RESULTS: Twenty-one patients (14.7%) demonstrated either hardware complication or fracture displacement within 6 months of surgery. Male sex was associated with a decreased risk of hardware complication (OR 0.11 [0.014, 0.86]; p=0.03). Posterior pelvic ring fixation at multiple sacral levels was associated with a decreased risk of fracture displacement (OR 0.21 [0.056, 0.83]; p=0.02). We were unable to demonstrate a significant association between preoperative radiographic characteristics and risk of hardware failure or fracture displacement. CONCLUSION: Our study demonstrates that both gender and the method of posterior fixation are associated with hardware failure or displacement.

Type II Odontoid Fractures Case Series: History of Seizures a Risk Factor for Failure of Non-operative Treatment of Type II Odontoid Fractures.

Introduction: Odontoid fractures are one of the most common injuries to the cervical spine. Type II odontoid fracture treatment varies depending on age, co-morbidities, and fracture morphology. Treatment ranges from cervical orthosis to surgical intervention. CurrentlyAt present, fractures with high non-union rates are considered for operative management which includes displacement of >6 mm, increasing age (>40--60 years), fracture gap >1 mm, delay in treatment >4 days, posterior re-displacement >2 mm, increased angulation, and history of smoking. While re-displacement of >2 mm has been associated with increased risk of non-union;, to the best of our knowledge, no studies have looked at the risk factors for re-displacement. Case Report: We present two 26-year-old male patients who were found to have minimally displaced type II odontoid fractures initially treated in a cervical collar. These two patients were subsequently found to have displaced their odontoid fracture after having a documented seizure. Conclusion: We suggest that a history of seizures be considered a risk factor for re-displacement of non-displaced type II odontoid fractures.

Effect of Titanium Miniplate Fixation on Hinge Fracture and Hinge Fracture Displacement Following Cervical Open-Door Laminoplasty.

BACKGROUND: Cervical spondylotic myelopathy is a neuromotor disorder responsible for functional limitations and decreased daily activities. Expansive open-door laminoplasty is the widely accepted procedure for the treatment of multilevel cervical spondylotic myelopathy. Among the various fixation procedures to secure the open lamina, miniplate fixation provides better clinical and radiological outcomes. However, the immediate effects on hinge fracture and hinge fracture displacement following miniplate fixation have not been proven until now. The purpose of our study was to elucidate the impact of cervical open-door angle on the status of spinal cord expansion and hinge fracture, hinge fracture displacement, and the role of implants used during surgery. METHODS: For this retrospective study, 122 patients who had undergone surgery from September 2016 to November 2017 with preoperative and postoperative radiographs were enrolled. Clinical and radiological outcomes were assessed before and after surgery. RESULTS: There were no significant differences in demographics, surgery time, blood loss, medical comorbidities, or perioperative and postoperative complications between 2 groups. The recovery rate and Nurick score before and at the follow-up show no statistical significance between the 2 groups, P value > .05 (P = .672) and P > .05 (P = .553), respectively. The statistical analysis shows that the mean hinge fracture in the miniplate group with a cervical open angle >30° was 2.42 ± 1.68 and with a <30° open angle, 0.05 ± 0.23; whereas, in the anchor group the mean hinge fracture in >30° cervical open angle was 2.227 ± 2.50 and in <30° was 0.409 ± 0.503. The results revealed statistical significance between 2 implant groups, P = .024 in the aspect of hinge fracture displacement and implant used. CONCLUSION: Laminoplasty by titanium miniplate fixation holds the laminae securely, prevents hinge fracture displacement, and promotes spinal cord expansion better than suture anchor fixation.

Early displacement of two part proximal humerus fractures treated with intramedullary proximal humeral nail.

INTRODUCTION: Proximal humerus nails (PHN) are commonly used for the treatment of simple proximal humerus fractures, and have a reported malunion rate of about 10%. The surgeons who used PHN in one medical institution have noticed a high rate of fracture re-displacement in the early post-operative period. This study's aim is to evaluate the rate of secondary displacement and malunion of patients treated for two part proximal humerus fractures with an angle-stable PHN (MultiLoc), and to assess possible risk factors for this secondary displacement. METHODS: A retrospective study comprised of 25 consecutive patients with 2 part surgical neck or metaphysis displaced proximal humerus fracture, treated with PHN between the years 2014-2017. Results assessed included radiographic measures (neck-shaft angle) and clinical data: range of motion (ROM) and functional scores (Constant, DASH, SSV). A univariate regression analysis was used to assess possible risk factors for secondary displacement. RESULTS: Mean age was 66.6 (range 17-93), and mean follow up was 20 months (range 6-40). Mean neck shaft angle (NSA) changed from 139.1° post operatively to 122.6° at last follow up, with 6 patients (24%) having a NSA change larger than 20°. Two patients (8%) ended up with NSA less than 90°, defined as malunion. The deltoid tuberosity index was found to correlate with the degree of displacement (-0.41, p = 0.04). CONCLUSIONS: PHN for simple displaced proximal humerus fractures was associated with fair clinical results but an unacceptable rate secondary displacement. The deltoid tuberosity index was found to correlate with the degree of this secondary displacement.

C1:C2 ratio is a potential tool assessing atlas fracture displacement and transverse ligament injury.

OBJECTIVES: The aim of this study was to determine the reliability of a C1:C2 ratio in a cohort of patients with atlas fractures. Second, we aimed to consider the utility of the C1:C2 ratio with regard to diagnosis of transverse ligament (TL) injury. DESIGN: This is a retrospective analysis. METHODS: Patients with atlas fractures in the Waikato region between 2008 and 2010 were identified retrospectively through clinical coding and collated radiology trauma database. MAIN OUTCOME MEASUREMENTS: The maximal width of C1 and C2 was measured using the first-taken trauma radiograph series. Combined overhang of lateral masses (△mm) and a C1:C2 ratio was then calculated. Final ratio and atlanto-dens interval (ADI) were measured at the last clinical follow-up. RESULTS: A total of 24 patients with full radiographic records were included. Of these, five patients (21%) had TL injuries confirmed on computed tomography or magnetic resonance imaging. No patient with a ratio 1.15 had an intact TL, whereas a ratio of >1.10 captured 80% of TL injuries. The ratio (P < 0.001) and delta values (P < 0.001) were statistically significantly different between TL-injured and TL-intact cohorts. Two patients in the TL injury group demonstrated increased ADI on final follow-up with a ratio of >1.10. CONCLUSIONS: A C1:C2 ratio >1.10 on plain radiographs showed a sensitivity of 80% in detecting atlas fractures with associated TL injury. All patients with a ratio of ≥1.15 had TL rupture subsequently confirmed by an advanced modality. A ratio calculation on radiographs is a potentially useful method of describing atlas lateral mass displacement. LEVEL OF EVIDENCE: Level III.

The magnitude of angular and translational displacement of dens fractures is dependent on the sagittal alignment of the cervical spine rather than the force of injury.

BACKGROUND CONTEXT: Although it is generally believed that the magnitude of dens fracture displacement is proportional to the amount of force applied to the cervical spine during injury, the factors responsible for displacement have not been studied. PURPOSE: Our aim was to determine factors that contribute to horizontal and angular displacement of dens fractures. STUDY DESIGN/SETTING: We conducted a retrospective review of adult patients who were admitted to our level 1 trauma center between January 1, 2008 and December 31, 2013. PATIENT SAMPLE: Angular and horizontal displacements of the fractured dens in 57 patients were measured. Subjects were grouped based on mechanism of fracture: motor vehicle accident, ground level fall, and higher falls. OUTCOME MEASURES: Cervical lordosis was measured between C2 and T1. C3-C4, C4-C5, C5-C6, and C6-C7 disc inclination angles were measured. Anteroposterior sagittal balance was assessed by comparing the sagittal position of the C2 body with the C7 body. METHODS: Data were analyzed using Pearson correlations, independent t tests, and support vector regression to construct predictive models that determine factors contributing to the angular and horizontal displacements. RESULTS: The mean horizontal displacement of the fractured dens was not significantly different among groups. However, the dens in those with ground level falls had a significantly greater mean fracture angle compared with the higher energy trauma groups (p=.01). There were positive correlations between angular displacement and C5-C6 disc space inclination angle (r=0.67, p<.01) and C6-C7 disc space inclination angle (r=0.61, p<.01). There were positive correlations between horizontal displacement and C6-C7 inclination angle (r=0.40, p<.01) and sagittal alignment (r=0.32, p<.01). The predictive model using all variables demonstrated that angular fracture displacement was only dependent on C5-C6 disc space inclination angle. Horizontal displacement was only dependent on C6-C7 inclination angle and anteroposterior sagittal balance. CONCLUSIONS: Disc space inclination angles of the lower cervical spine and the cervical sagittal balance most contribute to the magnitude of angular and horizontal displacement of the dens after fracture.

Early Weightbearing After Operatively Treated Ankle Fractures: A Biomechanical Analysis.

BACKGROUND: No consensus exists regarding the timing of weightbearing after surgical fixation of unstable traumatic ankle fractures. We evaluated fracture displacement and timing of displacement with simulated early weightbearing in a cadaveric model. METHODS: Twenty-four fresh-frozen lower extremities were assigned to Group 1, bimalleolar ankle fracture (n=6); Group 2, trimalleolar ankle fracture with unfixed small posterior malleolar fracture (n=9); or Group 3, trimalleolar ankle fracture with fixed large posterior malleolar fracture (n=9) and tested with axial compressive load at 3 Hz from 0 to 1000 N for 250 000 cycles to simulate 5 weeks of full weightbearing. Displacement was measured by differential variable reluctance transducer. RESULTS: The average motion at all fracture sites in all groups was significantly less than 1 mm (P < .05). Group 1 displacement of the lateral and medial malleolus fracture was 0.1±0.1 mm and 0.4±0.4 mm, respectively. Group 2 displacement of the lateral, medial, and posterior malleolar fracture was 0.6±0.4 mm, 0.5±0.4 mm, and 0.5±0.6 mm, respectively. Group 3 displacement of the lateral, medial, and posterior malleolar fracture was 0.1±0.1 mm, 0.5±0.7 mm, and 0.5±0.4 mm, respectively. The majority of displacement (64.0% to 92.3%) occurred in the first 50 000 cycles. There was no correlation between fracture displacement and bone mineral density. CONCLUSION: No significant fracture displacement, no hardware failure, and no new fractures occurred in a cadaveric model of early weightbearing in unstable ankle fracture after open reduction and internal fixation. CLINICAL RELEVANCE: This study supports further investigation of early weightbearing postoperative protocols after fixation of unstable ankle fractures.

Is Bone Grafting Necessary in the Treatment of Malunited Distal Radius Fractures?

Background Open wedge osteotomy with bone grafting and plate fixation is the standard procedure for the correction of malunited distal radius fractures. Bone grafts are used to increase structural stability and to enhance new bone formation. However, bone grafts are also associated with donor site morbidity, delayed union at bone-graft interfaces, size mismatch between graft and osteotomy defect, and additional operation time. Purpose The goal of this study was to assess bone healing and secondary fracture displacement in the treatment of malunited distal radius fractures without the use of bone grafting. Methods Between January 1993 and December 2013, 132 corrective osteotomies and plate fixations without bone grafting were performed for malunited distal radius fractures. The minimum follow-up time was 12 months. Primary study outcomes were time to complete bone healing and secondary fracture displacement. Preoperative and postoperative radiographs during follow-up were compared with each other, as well as with radiographs of the uninjured side. Results All 132 osteotomies healed. In two cases (1.5%), healing took more than 4 months, but reinterventions were not necessary. No cases of secondary fracture displacement or hardware failure were observed. Significant improvements in all radiographic parameters were shown after corrective osteotomy and plate fixation. Conclusion This study shows that bone grafts are not required for bone healing and prevention of secondary fracture displacement after corrective osteotomy and plate fixation of malunited distal radius fractures. Level of evidence Therapeutic, level IV, case series with no comparison group.