Comparative study of retrograde intramedullary nailing versus locking extramedullary plating in complete articular fractures with metaphyseal comminution of the distal femur.

INTRODUCTION: Fractures of the distal femur with metaphyseal comminution and complete intra-articular involvement (AO/OTA classifications 33C2 and 33C3) present challenges for reduction and fixation. However, an optimal fixation method remains unknown. This study aimed to compare the clinical and radiographic outcomes of locking extramedullary plating (LEP) and retrograde intramedullary nailing (RIN) for complete distal femoral intra-articular fractures with metaphyseal comminution. MATERIALS AND METHODS: Between January 2016 and May 2022, 80 patients (45 men and 35 women; average age, 56.7 years) diagnosed with AO/OTA 33C2 and 33C3 were treated with either LEP or RIN and followed up for at least one year. Post-operative evaluations included radiographic assessments of bone union rate, timing, and alignment. Clinically, the knee joint range of motion (ROM), lower extremity functional scale (LEFS), and Kellgren and Lawrence (KL) grade were analyzed. The complications were also compared. RESULTS: 36 underwent LEP and 44 underwent RIN. Bone union was observed in 69.4% and 63.6% of the patients in the LEP and RIN groups, respectively (p = 0.64). The average union time was 6.9 months for the LEP group and 6.6 months for the RIN group (p = 0.51). A tendency toward varus deformity was observed in the RIN group, although the difference was not statistically significant. No significant differences were observed in knee ROM, LEFS, or KL grade. Complications included non-union (33.8%; RIN, 11; LEP, 16), varus deformity (5%; RIN, 4; LEP, 0), infection (1.3%; RIN, 0; LEP, 1), heterotrophic ossification (1.3%; RIN, 0; LEP, 1), and wound dehiscence (2.5%; RIN, 2; LEP, 0). CONCLUSIONS: The surgical fixation methods, RIN and LEP, for complete distal femoral intra-articular fractures with metaphyseal comminution showed similar clinical and radiological outcomes. However, regardless of the type of fixation device used, there was a reduced rate of bone union owing to high energy and a less favorable prognosis.

Biomechanical Comparison of Fixation Methods for Posterior Wall Fractures of the Acetabulum: Conventional Reconstruction Plate vs. Spring Plate vs. Variable Angle Locking Compression Plate.

Background and Objectives: Acetabular fractures, though infrequent, present considerable challenges in treatment due to their association with high-energy trauma and poor prognoses. Posterior wall fractures, the most common type among them, typically have a more favorable prognosis compared to other types. Anatomical reduction and stable fixation of the posterior wall are crucial for optimal treatment outcomes. This study aimed to biomechanically compare three commonly used fixation methods for posterior wall fractures of the acetabulum-a conventional reconstruction plate, a spring plate, and a 2.7 mm variable angle locking compression plate (VA-LCP). Materials and Methods: The study utilized 6 fresh-frozen cadavers, yielding 12 hemipelvises free from prior trauma or surgery. Three fixation methods were compared using a simple acetabulum posterior wall fracture model. Fixation was performed by an orthopedic specialist, with prebending of plates to minimize errors. Hemipelvises were subjected to quasi-static and cyclic loading tests, measuring fracture gap, stiffness, and displacement under load. Results: It showed no significant differences in fracture gap among the three fixation methods under cyclic loading conditions simulating walking. However, the conventional reconstruction plate exhibited a greater stiffness compared to the spring and variable angle plates. Fatigue analysis revealed no significant differences among the plates, indicating a similar stability throughout cyclic loading. Despite differences in stiffness, all three fixation methods demonstrated adequate stability under loading conditions. Conclusions: While the conventional reconstruction plate demonstrated a superior stiffness, all three fixation methods provided sufficient stability under cyclic loading conditions similar to walking. This suggests that postoperative limitations are unlikely with any of the three methods, provided excessive activities are avoided. Furthermore, the variable angle plate-like the spring plate-offers an appropriate stability for fragment-specific fixation, supporting its use in surgical applications. These findings contribute to understanding the biomechanical performance of different fixation methods for acetabular fractures, facilitating improved surgical outcomes in challenging cases.

Risk factors for pubic ramus fracture nonunion after conservative treatment of pelvic ring injuries: a retrospective cohort multicenter study.

PURPOSE: To determine the incidence of nonunion, clinical and radiological outcomes, and risk factors for nonunion in conservatively treated pubic ramus fractures among patients diagnosed with pelvic ring injury. METHODS: A total of 546 patients (192 men, 354 women) diagnosed with pubic ramus fracture, treated conservatively, and who had completed > 1 year follow-up at three level 1 trauma centers between January 2014 and December 2020, were enrolled. Clinical and radiological evaluations were compared between union and nonunion groups. Logistic regression and Kaplan-Meier analyses were used. RESULT: At the final follow-up, 527 (96.5%) and 19 (3.5%) patients had union and nonunion of fractures, respectively. The union and nonunion groups exhibited statistically significant differences in posterior injury (p = 0.040), bilateral ramus fracture (p < 0.001), initial displacement (p < 0.001), and clinical result (p < 0.001). In the multivariate logistic regression analysis, initial displacement (odds ratio, 4.727; p = 0.005) was analyzed as a risk factor for nonunion. According to the Kaplan-Meier analysis, the median initial displacement of nonunion occurrence was 17.9 mm (standard error, 1.211; 95% confidence interval 15.526-20.274), and nonunion patients were included if the displacement was > 15.9 mm (standard error, 1.305) on the 75th percentile. CONCLUSION: Conservative treatment is ineffective in some ramus fracture cases with pelvic ring injury. As ramus nonunion causes functional deterioration, active treatment is required if the displacement is ≥ 16 mm.

Comparison between anterior and posterior plating systems in extra-articular distal-third diaphyseal humeral fractures.

PURPOSE: The ideal surgical treatment of extra-articular distal-third diaphyseal humeral fractures is controversial in terms of the surgical approach and plate position. The aim of this study was to compare the clinical and radiological outcomes between anterior and posterior plating methods for extra-articular distal-third diaphyseal humeral fractures. METHODS: Twenty-four patients were treated with anterior plating with modified placement of the proximal humeral internal locking system (PHILOS) plate, and 22 patients were treated with posterior plating of the extra-articular distal humerus plate (EADHP). Patient demographics, the fracture configuration, the number of screws in the distal fragment, the operation time, and the time to union were analyzed. The range of elbow motion, Mayo elbow performance score (MEPS), plate-related symptoms, and complications were evaluated at the final follow-up. RESULTS: There were no statistically significant differences in the demographic data between the two groups. The mean operation time for anterior plating (108.2 ± 24.5 min) was significantly shorter than that for posterior plating (144.2 ± 29.5 minutes, p < 0.001). The average number of screws used in the distal humeral fragment was significantly higher with anterior plating (5.7 ± 0.7) than with posterior plating (4.8 ± 0.5, p < 0.001). No patients in the anterior plating group had plate-related symptoms, while 17 patients in the posterior plating group (77%) had discomfort or cosmetic problems related to the plate (p < 0.001). Plate removal was performed upon patient request in nine patients of the posterior plating (52.9%) and four (17%) in anterior plating (p = 0.040). Nonunion occurred in one patient who underwent anterior plating, and one patient who underwent posterior plating had post-operative radial nerve palsy. There were no significant differences in the MEPS or elbow range of motion between the two surgical methods. CONCLUSION: Both anterior and posterior plating provide satisfactory clinical and radiologic outcomes for extra-articular distal-third diaphyseal humeral fractures. Despite the satisfactory outcomes, however, posterior plating is highly associated with plate-related complaints, which might be one of the considerations when the surgical method is selected for extra-articular distal-third diaphyseal humeral fractures.

Outcomes of embedded rafting k-wire technique for intermediate articular fragment fixation in comminuted olecranon fractures.

BACKGROUND: Severely comminuted olecranon fractures are challenging injuries. Commonly used tension band wiring exerts excessive compressive forces causing olecranon shortening and joint incongruity. This study aimed to introduce the embedded rafting k-wire technique with the bridging technique for intermediate articular fragment fixation in comminuted olecranon fractures and evaluate its clinical and radiological outcomes. MATERIALS AND METHODS: A total of 34 patients with comminuted olecranon fractures were treated with rafting k-wire fixation combined with a locking plate. Time to union, the number of rafting k-wires in the intermediate articular fragment, quality of joint reduction, and secondary reduction loss were analyzed. Elbow range of motion, Mayo Elbow Performance Score (MEPS), and complications were evaluated at the final follow-up. RESULTS: Fracture union was obtained in all patients. The mean number of intermediate articular fragments was 2.4 ± 0.7, and the average number of rafting k-wires was 3.0 ± 1.2. There were mild and moderate degree early posttraumatic osteoarthritis in 6 cases (17.6%) at the mean 20.8 months of follow-up. At the final follow-up, the mean range of elbow motion was 4.6° of flexion contracture and 133.5° of further flexion. The average MEPS was 97.1 (range, 75-100). Two patients had heterotrophic ossification without functional impairment. CONCLUSION: The embedded rafting k-wire technique with bridging plates in comminuted olecranon fractures exhibited satisfactory outcomes. This method might serve as an alternative when considering the ability to restore articular congruency and stability in severely comminuted olecranon fragments. LEVEL OF EVIDENCE: Level IV, therapeutic.

Minimally invasive plate osteosynthesis for proximal humeral fractures: clinical and radiologic outcomes according to fracture type.

BACKGROUND: This study evaluated the clinical and radiologic outcomes, according to fracture type, of proximal humeral fractures treated by the minimally invasive plate osteosynthesis (MIPO) technique. MATERIALS AND METHODS: Of 85 patients with proximal humeral fractures who were treated by the MIPO technique, 62 were evaluated: 27 with 2-part fractures, 24 with 3-part fractures, and 11 with 4-part fractures. An additional inferomedial screw or fibular allograft was used when severe medial cortical comminution was found in the proximal humerus. Clinical and radiographic outcomes were evaluated during the follow-up of 37 months. RESULTS: There was a significant difference in the Constant scores of patients with 4-part fractures compared with those with 3-part fractures (P = .039). The neck-shaft angle in 4-part fractures (121° ± 3°) at final follow-up was significantly lower compared with other fracture types (2-part: 129° ± 9°, P = .036; 3-part: 129° ± 2°, P = .031). Complication rates (72.7%) of 4-part fractures were significantly higher than with other fracture types (2-part, 7.4%; 3-part, 20.8%; P = .001). Sixteen fractures were fixed with an additional inferomedial screw, and 3 patients had insertion of a fibular allograft. CONCLUSION: Satisfactory clinical and radiologic outcomes were obtained by the MIPO technique in proximal humeral fractures. In addition, medial cortical support can be performed with an inferomedial screw or fibular allograft in the MIPO technique. However, the MIPO technique for 4-part fractures showed relatively inferior outcomes compared with 2- and 3-part fractures. Conversion to open plating is also considered if adequate reduction, that is, a neck-shaft angle >120°, is not able to be obtained in the MIPO technique for 4-part fractures of the proximal humerus.

Mortality Rate and Outcomes of Omicron Variant Positive Patients with Osteoporotic Fractures: A Retrospective Study.

BACKGROUND: During the lockdown period associated with the coronavirus disease 2019 (COVID-19) pandemic, increased mortality rates among patients with COVID-19 have been reported. This study aimed to analyze the mortality rate of osteoporotic hip fractures in patients who were COVID-19-positive after the lockdown during the Omicron period. METHODS: A retrospective study was performed with 194 patients who were aged 70 years or more and diagnosed with osteoporotic hip fracture. The patients were divided into two groups according to their COVID-19 diagnoses. Surgery was performed within 10 days of diagnosis. Age, sex, past medical history, time until surgery, postoperative complications, and the primary outcome of mortality rate at 30 and 90 days were analyzed. RESULTS: Among the 194 patients, 13 and 181 were in the COVID-19-positive and negative group, respectively. The total, 30-day, and 90-day mortality rates in the control and COVID-positive group were 11% and 0% (P=0.368), 1.7% and 0% (P=1.000), and 5.0% and 0% (P=1.000), respectively. No significant differences were observed in age, sex, history, time to surgery, postoperative complications, or postoperative mortality. In 1:1 propensity score matching, the time to surgery was 5.34 days in patients who were COVID-19-positive, and 3.00 days in patients who were COVID-19 negative, with no statistical significance (P=0.09). Age, sex, medical history, postoperative complications, and postoperative mortality were not significantly different between the groups. CONCLUSIONS: Regardless of the COVID-19 diagnosis, surgical treatment without delay is believed to result in positive outcomes in older patients with osteoporotic hip fractures, as no significant differences in mortality rate and respiratory complications were observed between patients who were COVID-19-positive and those who were COVID-19 negative.

Radiographic outcomes and non-union factor analysis in fragmentary segmental femoral shaft fractures (AO/OTA 32C3) treated with reamed antegrade nailing.

This study retrospectively assessed radiographic outcomes and risk factors associated with non-union in femoral shaft fragmentary segmental fractures (AO/OTA 32C3) treated with reamed antegrade intra-medullary nailing. Radiological outcomes, including union and alignment, were evaluated. The risk factors for non-union were investigated, including demographics and treatment-related characteristics, such as the number of interlocking screws, segmentation length, main third fragment length, distance of the main third fragment, width ratio and exposed nail length in one cortex from immediate post-operative radiographs. Multivariate logistic regression was used for statistical analysis. Among 2295 femoral shaft fracture patients from three level-1 trauma centers, 51 met the inclusion criteria. The radiological union was achieved in 37 patients (73%) with a mean union time of 10.7 ± 4.8 months. The acceptable axial alignment was observed in 30 patients (59%). Multiple logistic regression analysis identified only exposed nail length as a significant risk factor for non-union (odds ratio: 1.599, p = 0.003) and the cut-off value was 19.1 mm (sensitivity, 0.786; specificity, 0.811). The study revealed high rates of non-union (27%) and malalignment (41%). Therefore, patients who underwent intramedullary nailing with an exposed nail length greater than 19.1 mm or about twice the nail diameter should be cautioned of the potential non-union.

Duration of in vitro storage affects the key stem cell features of human bone marrow-derived mesenchymal stromal cells for clinical transplantation.

BACKGROUND AIMS: Mesenchymal stromal cells (MSCs) have the ability to self-renew and differentiate into various cell types. Their plasticity and easy availability make them promising candidates for regenerative medicine. However, for successful clinical application, MSCs need to be expanded under a Good Manufacturing Practices-compliant system to obtain a large quantity of these cells. Although the viability and potency of these in vitro-expanded MSCs need to be maintained during preparation and transportation before transplantation, these characteristics have not thoroughly been examined. Our goal in this study was to standardize MSC preparation and storage before their clinical application to ensure reproducible quality and potency for their clinically intended purpose. METHODS: We examined the viability, self-renewal capacity and differentiation capability of MSCs on short-term in vitro storage in saline or dextrose solution at 4°C and room temperature. RESULTS: MSCs harvested and suspended in saline for 1-2 h showed >90% viability regardless of storage temperature. However, when cells were stored for >2 h in saline, their viability decreased gradually over time. The viability of cells in dextrose deteriorated rapidly. MSCs lost colony-forming unit and differentiation capacities rapidly as storage time increased. Collectively, we found that a storage period >2 h resulted in a significant decrease in cell viability, cell proliferation capacity and differentiation potency. CONCLUSIONS: Storage of culture-harvested MSCs for >2 h is likely to result in suboptimal MSC-mediated tissue regeneration because of decreased cell viability and differentiation capacity.

Fibular Fixation in Same-Level Distal Third Tibiofibular Fractures: Is Fibular Fracture Regarded as a Secondary Importance?

Background: Although most studies focused on the alignment or union of the tibia in same-level distal third tibiofibular fractures, the outcome of a concomitant fibular fracture is generally regarded as being of secondary importance in the literature. This study aimed to assess the outcomes of fibular fractures in same-level distal third tibiofibular fractures. Methods: In this retrospective study, we enrolled 111 patients with same-level distal third tibiofibular fractures treated at our institute between January 2016 and August 2020. Tibial fractures were stabilized with intramedullary nailing, and the cases were divided into two groups based on whether they additionally underwent fibular fixation (group 1, 57 cases) or not (group 2, 54 cases). Clinical and radiographic outcomes were used for the evaluation of tibial and fibular alignments, union of the tibia and fibula, number of interlocking screws in the distal tibial fragment, range of motion of the ankle joint, and complications. Results: No statistically significant differences in the tibial union rate or mean tibial alignment were observed between the two groups on either the immediate postoperative or final radiographs. The fibular union rate in group 1 was significantly higher than that in group 2 (fibular nonunion, 0 vs. 15; p < 0.001). Statistically significant differences in fibular displacement were observed on immediate postoperative radiographs between patients with fibular union and those without it. At the final follow-up, the mean range of ankle motion and lower extremity functional scale scores did not differ between the two groups. Conclusions: Regardless of whether fibular fixation was performed, the overall tibial alignment with intramedullary nailing was well restored and the union rate of the tibia was comparable in the two groups. Fibular nonunion is not uncommon in unfixed fibula fractures. Displacement of the fibula as seen on immediate postoperative radiographs was related to fibular nonunion.

Minimally invasive plate osteosynthesis using anterior-inferior plating of clavicular midshaft fractures.

INTRODUCTION: This study evaluated the clinical and radiological outcomes of acute displaced clavicular midshaft fractures treated with minimally invasive plate osteosynthesis (MIPO). MATERIALS AND METHODS: Fifteen patients with acute displaced clavicular midshaft fractures underwent MIPO. A locking reconstruction plate was applied on the anterior aspect of the clavicle through two small incisions. Functional outcomes were assessed using range of shoulder motion and University of California Los Angeles (UCLA) shoulder score. Radiological evaluation included time to union, fracture healing, and clavicular length difference measured as proportional length difference with the unaffected side. RESULTS: All fractures healed within a mean of 15.1 weeks postoperatively. The mean proportional length difference was 0.66 ± 2.2% compared with the unaffected arm. Shoulder motion recovered to pre-injury activity level in all patients. The UCLA shoulder scores showed excellent results in 13 patients and good results in two patients. Nonunion and implant failures were not found in any patients. One patient complained of temporary hypoesthesia around the lateral clavicle area. CONCLUSIONS: MIPO using anterior-inferior plating for acute displaced clavicular midshaft fractures provided satisfactory clinical outcomes without serious complications and could be an effective alternative option to conventional operative treatments.

Computational simulation of cephalomedullary nailing in the osteoporotic Asian femur and clinical implications.

PURPOSE: To assess the conformity of PFNA-II® and introduce clinical implications of new cephalomedullary nail (CMN) by analyzing three-dimensional (3D) modeling with virtual implantation at the actual size. MATERIALS AND METHODS: Thirty-four patients (average age; 79 years, range 68-94 years) who sustained the intertrochanteric fracture of the femur were enrolled in the present study. After importing into Mimics® software, the intact femurs on the opposite side were selected as cropping areas to reconstruct the 3D femur model with the medullary canal. PFNA-II® and new CMNs (lateral angle 0° and 2°, CCD angle 130°; CMN0° and CMN2°) were processed at the actual size and ideally placed in the proximal femur using Mimics® software. The virtual entry point (EP), nail conformity, and anatomical relationships with the adjacent structures were assessed. RESULTS: The virtual EP of PFNA-II® was placed along the cervico-trochanteric (CT) junction in the posterior half around trochanteric fossa and always medial to the tip of greater trochanter (GT). There were six abutments in PFNA-II® models, one impingement in CMN 0°, and no impingement in CMN 2°. All the models with cortical abutment showed increased anterior and lateral bowing of the proximal shaft owing to age-dependent changes. Compared with PFNA-II®, with a decreasing tendency on the mediolateral angle of new CMNs, the virtual EP shifted to the medial and anterior side towards the CT junction. By simulating the intentional positioning in the media-to-lateral direction, the abutments in the PFNA-II® model could not be avoided. Furthermore, the lag screw of CMN 0° was placed ideally at the center or inferior side of the femoral head < 10 mm in any direction without a cortical abutment. CONCLUSION: To avoid cortical abutment of CMN in the Asian geriatric femur, the virtual EP would be technically placed in the medial to the GT tip, and the implant design should be changed to decrease the mediolateral angle.

Percutaneous bridge plating of extra-articular distal fibular fracture for the management of distal tibia type III open fracture.

PURPOSE: The aim of this study is to conduct clinical and radiographic evaluations of the use of percutaneous bridge plating for distal fibular fractures combined with distal tibia type III open fractures. METHODS: Thirty-four patients with acute distal third fibular shaft fractures (4F2A(c) and 4F2B(c) according to the AO/OTA classification) combined with distal tibia type III open fractures were enrolled. Concurrent fibular fractures were fixed with the percutaneous bridge plating simultaneously, while distal tibia open fractures were temporally stabilized with a spanning external fixator. Clinical and radiographic outcomes were evaluated using the Lower Extremity Functional Scale (LEFS), the proportional length difference of the fibula, the talocrural angle, the union rate of the fibula and tibia, the operation time, and complications at the final follow-up. RESULTS: All fibular fractures healed with an average bone healing time of 20.7 ± 6.3 weeks (range, 16-35). The mean proportional length difference was 0.492 ± 0.732% compared with that in the uninjured fibula. The functional assessment result according to the LEFS was 74.0 ± 3.70 points (range, 57-80). No cases of fibula fracture infection developed throughout the follow-up period in any of the patients. Iatrogenic postoperative superficial peroneal nerve injury was not found in any of the patients. CONCLUSION: With the perspective of minimizing soft tissue problems due to high-energy trauma, the application of percutaneous bridge plating for the treatment of distal fibular fractures can be an alternative to conventional treatment methods.

Clinical outcomes of osteosynthesis of well-fixed periprosthetic proximal tibial fractures (Felix type 2A) after total knee arthroplasty.

AIMS: This study aimed to evaluate the clinical and radiologic outcomes of well-fixed periprosthetic tibial fractures after TKA. PATIENTS AND METHODS: The medical records of patients who presented with Felix type 2A periprosthetic tibial fractures after TKA between March 2015 and February 2020 were retrospectively obtained from 5 institutions. Data on injury mechanism, fracture pattern including open fractures and Felix classification, and surgical method were recorded. Functional outcomes including range of motion (ROM) and Knee Society Score (KSS) at postoperative 1 year were reviewed. The need for reoperation was also reviewed. Radiologic findings included union time and mechanical proximal tibial angle (MPTA) at the last radiologic follow-up. RESULTS: Eighteen patients (13 women, 5 men; average age, 73.9 years) were included. The average follow-up duration was 20.8 months. The fractures resulted from high-energy (11 cases) and low-energy (7 cases) injuries. Two cases involved open fractures. Anatomical locking plates were used in all cases: single plate (4 cases) and dual plates (14 cases). The average number of proximal screws was 7.1 (range, 4-9). All patients achieved bone union at an average of 18.6 weeks without secondary intervention. No infection occurred; however, 1 patient with skin necrosis required local flap. Implant removal was performed in 5 cases: 1 case, skin defect and 4 cases, discomfort due to plate prominence. The average ROM and KSS were 120.3° and 85.9, respectively. The mean MPTA was 87.8°; the MPTA was higher in the single-plate group (94.0° vs. 88.1°, p=0.013). Three cases involved values beyond the normal MPTA range (85-90°): 104° and 96° with a single plate and 92° with dual plates. The malalignment rate was higher in the single-plate group (p=0.043). CONCLUSION: Felix type 2A periprosthetic tibial fractures treated with minimally invasive osteosynthesis showed excellent clinical outcomes, and tibial alignment was well maintained in the dual-plate group.

A clinical comparison of two different double plating methods for intraarticular distal humerus fractures.

BACKGROUND: This study compared clinical outcomes in patients with intraarticular distal humerus fractures treated using 2 different double plating methods. METHOD: Seventeen patients were treated by perpendicular plating (group I) and 18 by parallel plating (group II) methods. Arc of flexion averaged 106 degrees +/-23 degrees in group I and 112 degrees +/-19 degrees in group II. RESULTS: Eleven patients in group I recovered full arc of flexion and 13 patients in group II achieved full arc of flexion. All patients obtained bone union, except 2 patients in group I. Nonunion in these patients developed in the supracondylar area. Complications developed in 6 patients in group I and in 8 in group II. No significant differences were found between the clinical outcomes of the 2o plating methods. CONCLUSION: Although more patients failed to achieve bony union in the perpendicular plating group, both parallel and orthogonal plates positioning can provide adequate stability and anatomic reconstruction of the distal humerus fractures. LEVEL OF EVIDENCE: 2.

The usefulness of reformatting CT scanning plane to distinguish sacral dysmorphism and introducing the variable of elevated height for predicting the possibility of trans-sacral screw fixation.

INTRODUCTION: Ilio-sacral screw fixation has been used for sacral fractures and sacroiliac joint dislocations. However, it is associated with significant complications including screw loosening with backing-out and loss of reduction. Trans-sacral screw fixation is indicated for rigid fixation in specific circumstances including bilateral posterior ring injuries, osteoporotic bone, or to supplement other types of posterior ring fixation. HYPOTHESIS: The reformatting the CT scanning plane may distinguish sacral dysmorphism and predict the possibility of trans-sacral screw fixation by introducing the new indicator. MATERIAL AND METHODS: The CT data of 112 adult cadavers (61 males and 51 females) were imported into Mimics® software and a 7.0 mm-sized trans-sacral screw was virtually placed in the ideal position of S1. The osseous widths around screw in the axial images (AxWS1) were measured. By reformatting the CT scanning plane parallel to the superior endplate of S1, the AxWRS1 was measured and the height of elevated segment in the upper sacrum (elevated height) was assessed as a new preoperative indicator. RESULTS: Cortical violation around screw was detected in 26 models and was considered as sacral dysmorphism. The average AxWS1 was measured as 13.70±2.76mm in the non-dysmorphism group, and 5.81±2.19mm in the dysmorphism group, with statistical difference (p<0.001). By reformatting the CT scanning plane, the average AxWRS1 increased to 16.61±2.79mm in the non-dysmorphism group, and 8.04±2.62 in the dysmorphism group, and the difference was statistically significant (p<0.001). The elevated height was 3.29±4.19mm in the non-dysmorphism group, and 17.52±3.09mm in the dysmorphism group, and the differences were statistically significant (p<0.001). Based on the ROC curve analysis, the cut-off value of elevated height was 12.90mm (sensitivity 1.0 and specificity 1.0). DISCUSSION: By reformatting the CT scanning plane, the osseous width around screw was widened, and the new preoperative indicator of elevated height could be introduced to predict the possibility of trans-sacral screw fixation into S1. If the elevated height exceeded 13mm, the pelvis was assigned to sacral dysmorphism and thus, could not apply the trans-sacral screw fixation into S1. LEVEL OF EVIDENCE: III, controlled laboratory study.

Review of bone graft and bone substitutes with an emphasis on fracture surgeries.

BACKGROUND: Autogenous bone graft is the gold standard bone graft material. However, due to limitations of supply and morbidity associated with autograft harvest, various bone substitutes have been considered. This article aims to review the properties of the bone graft and various bone substitutes currently available in orthopedic surgery. MAIN BODY: Synthetic bone substitutes consist of hydroxyapatite, tricalcium phosphate, calcium sulfate, or a combination of these minerals. Synthetic porous substitutes share several advantages over allografts, including unlimited supply, easy sterilization, and storage. However, they also have some disadvantages, such as brittle properties, variable rates of resorption, and poor performance in some clinical conditions. Recently, attention has been drawn to osteoinductive materials, such as demineralized bone matrix and bone morphogenetic proteins. CONCLUSION: Despite tremendous efforts toward developing autograft alternatives, a single ideal bone graft substitute has not been developed. The surgeon should understand the properties of each bone graft substitute to facilitate appropriate selection in each specific clinical situation.

Modified use of a proximal humeral internal locking system (PHILOS) plate in extra-articular distal-third diaphyseal humeral fractures.

BACKGROUND: Surgical treatment of extra-articular distal-third diaphyseal humeral fractures is controversial in terms of surgical approach and position of implant. The aim of this study is to evaluate the clinical and radiological outcomes of a modified application of the proximal humeral internal locking system (PHILOS) plate in extra-articular distal-third diaphyseal humeral fractures. MATERIALS AND METHODS: A total of 23 patients with extra-articular distal humerus fractures were treated using either open plating or the minimally invasive plate osteosynthesis (MIPO) technique with upside down application of the PHILOS plate. Fracture configuration, number of screws in the distal fragment, and time to union were analysed. Elbow range of motion, Mayo Elbow Performance Score (MEPS), and complications were evaluated at the final follow-up. RESULTS: Fracture union was obtained in all patients at a mean postoperative time of 20.8 ± 2.9 weeks. The mean shortest and longest cortical lengths were 50.7 ± 14.0 mm and 85.2 ± 12.4 mm, respectively. The average number of screws in the distal humeral fragment was 5.6 ± 0.7. No statistically significant correlation was observed between the shortest cortical length and number of screws in the distal fragment (p = 0.224) or between the longest cortical length and the number of screws in the distal humeral fragment (p = 0.956). The average MEPS was 97.6 (range, 75-100). No postoperative complications that required reoperation were occured. CONCLUSION: A modified anterior application of the PHILOS plate in extra-articular distal-third diaphyseal humeral fracture showed satisfactory outcomes, so it is an alternative when considering the ability to increase plate-screw density with locking screw fixation in a distal humeral fragment. LEVEL OF EVIDENCE: Therapeutic level IV, case series.

Analysis of complications and clinical outcomes in the treatment of segmental tibial fractures according to the method of internal fixation.

BACKGROUND/OBJECTIVE: We compared and analysed not only the clinical and radiological results of surgery but also the complications according to the definitive fixation method. METHODS: We retrospectively reviewed the medical records and radiographs of all segmental tibial fracture patients treated with either intramedullary nailing or minimally invasive plate osteosynthesis between 2010 and 2017. We enrolled 69 patients. RESULTS: The patients' mean age was 48.6 years (25-74). Forty-nine patients had open fractures (Type I, 20; Type II, 9; Type III, 20) and six had acute compartment syndrome. The initial stabilisation method was intramedullary nailing in 28 patients (40.6%). The time to definitive fixation was longer in the minimally invasive plate osteosynthesis group (mean, 8.8 days; range, 0-27) than that in the intramedullary nailing group (mean, 3.9 days; range, 0-35), with a statistically significant difference (p = 0.001). Thirteen patients developed nonunion (five with minimally invasive plate osteosynthesis and eight with intramedullary nailing, p = 0.076). Complications were noted in 18 patients (26.1%), including five with infection. There was no significant difference in the clinical and radiological outcomes according to the definitive fixation method. A multivariate logistic regression analysis indicated that age (odds ratio, 1.112; 95% confidence interval, 1.022-1.210; p = 0.013) and smoking (odds ratio, 13.976; 95% confidence interval, 1.599-122.150; p = 0.017) correlated with the occurrence of complications. CONCLUSIONS: The results of our study suggest that if soft-tissue handling and restoration of bony alignment are successful, both intramedullary nailing and minimally invasive plate osteosynthesis will be effective treatment methods for segmental tibial fractures.

Anatomically Precontoured Locked Plates in Pilon Fractures: A Computed Tomography Based and Cadaveric Study.

BACKGROUND: The treatment of comminuted tibia plafond fractures remains clinically challenging due to the complexity of the articular fracture pattern despite using the anatomically precontoured locked plates. This study describes the morphologic characteristics of the anterolateral fragment and to evaluate the fixability of the anterolateral fragment with the anatomically precontoured locked plate in the pilon fracture. MATERIALS AND METHODS: One hundred and twenty five cases of AO 43-B and C fracture were evaluated using the computed tomography (CT) scan. The anterior-posterior distance in CT (APDc), medial-lateral distance in CT (MLDc), coronal and sagittal height, and articular surface area of the anterolateral fragment were measured in CT. Four types of anatomically precontoured locked plates were used for cadaveric measurement. Four cadaveric parameters were also evaluated; anteroposterior distance in plate (APDp), height of the screw in the medial plate, medial-lateral distance in plate (MLDp), and height of the screw in the anterolateral plate. RESULTS: The anterolateral fragment was described with a mean surface area of 167.13 mm2 (APDc: 10.89 ± 4.64 mm, MLDc: 15.02 ± 6.56 mm, sagittal height: 14.85 ± 6.25 mm, and coronal height: 17.27 ± 6.88 mm). The cadaveric measurement showed that the juxta-articular screw of the medial distal tibia plate was placed away from the anterolateral fragment. The anterolateral distal tibia plate did not purchase the anterolateral fragment due to the higher position of the most distal-lateral screw (Synthes 18.37 ± 1.86 mm and Zimmer 17.78 ± 2.37 mm of the height of screw in the anterolateral plate). CONCLUSION: Anatomical distal tibial locked plates did not take purchase on the anterolateral fragment in pilon fracture in the best anatomical fit. Preoperative CT measurement can be used for determining a fixation strategy for the anterolateral fragment. In addition, a newly designed anterolateral distal tibia plate can be another solution when the usual anatomically precontoured distal tibia locked plate fails to cover the anterolateral fragment.