The modified Hardinge approach is not inferior to trochanteric flip osteotomy for Pipkin type IV femoral head fractures: a comparative study in 40 patients.

PURPOSE: To compare the modified Hardinge approach and trochanteric flip osteotomy for the treatment of Pipkin type IV femoral head fractures. METHODS:  This retrospective study included 40 patients who underwent surgical treatment for Pipkin type IV femoral head fractures between 2011 and 2020 and completed at least 1 year of follow-up. The clinical outcome of the Merle d'Aubigné-Postel score and radiological outcomes, including the quality of the fracture reduction, osteonecrosis of the femoral head, posttraumatic osteoarthritis, and heterotopic ossification, were compared between the two groups. Conversion to total hip replacement was recorded as the main outcome measure, analyzed by Kaplan-Meier curve and log-rank test. RESULTS: Nineteen and 21 patients were treated using the modified Hardinge approach (Group A) and trochanteric flip osteotomy (Group B), respectively. The estimated surgical blood loss was significantly higher in Group B (500.00 ± 315.44 mL vs. 246.32 ± 141.35 mL; P = 0.002). Two patients in Group B complained of discomfort caused by the trochanteric screws and requested implant removal. Radiographic outcomes did not differ significantly between the two groups. Clinical outcomes assessed using the Merle d'Aubigné-Postel score 1 year after injury were nearly identical (P = 0.836). Four (21.1%) patients in Group A and three (14.3%) patients in Group B underwent conversion to total hip replacement during the follow-up period; the log-rank test showed no significant difference (P = 0.796). CONCLUSIONS: The modified Hardinge approach resulted in reduced blood loss, with clinical and radiological outcomes similar to those of trochanteric osteotomy; thus, it is an acceptable alternative to trochanteric flip osteotomy.

Critical distance of the sacroiliac joint for open reduction using screw fixation for traumatic sacroiliac joint diastasis: a retrospective study.

BACKGROUND: Osteosynthesis for sacroiliac joint (SIJ) diastasis using an iliosacral screw (ISS) and a trans-iliac-trans-sacral screw (TITSS) can be performed using a closed or an open method. However, no clear indication for open reduction has been established. METHODS: Data on patients with unilateral traumatic SIJ diastasis who underwent ISS and TITSS fixation were retrospectively collected and separated into groups according to the reduction method: closed reduction group (C group) and open reduction group (O group). Demographic data and perioperative image assessments were compared between the groups. The critical distance of the SIJ was identified to elucidate the indication for open reduction of the diastatic SIJ. RESULTS: Fifty-six patients met the inclusion criteria over a 3-year period. There was no significant difference in the reduction quality of pelvic ring injuries between the groups, according to Matta's and Lefaivre's criteria. The improvement in the SIJ distance was significantly greater in the O group than in the C group in the axial plane on multiplanar computed tomography (p = 0.021). This model predicted that a difference of > 3.71 mm between the injured and healthy SIJ was a recommended indication for open reduction, with an area under the curve of 0.791 (95% confidence interval 0.627-0.955, p = 0.004). CONCLUSIONS: Open reduction for SIJ diastasis might achieve better reduction quality than does closed reduction in the axial plane in selected cases. When the difference between the injured and healthy SIJ was wider than 3.71 mm, open reduction was recommended for satisfactory radiological outcomes.

Does a simultaneous ventral/dorsal approach provide better reduction quality in treating acetabular fracture involving both columns with displaced posterior wall?

INTRODUCTION: Various surgical techniques have been proposed to manage acetabular fractures involving both columns with posterior wall displacement. However, the optimal surgical approach to achieve satisfactory reduction quality remains controversial. MATERIALS AND METHODS: This retrospective study evaluated 34 patients with fractures who were treated at a single medical institution. The patients were divided into two groups according to the ventral/dorsal surgical approach employed: simultaneous (SI) and sequential (SE). Perioperative parameters, as well as radiological and functional outcomes, were analyzed and compared between the two groups. RESULTS: The SI and SE groups comprised 9 and 23 out of the 34 patients, respectively. The SI group exhibited a significantly shorter surgical time and lower estimated blood loss than the SE group (p = 0.04 and 0.03, respectively). The quality of reductions of the anterior and posterior columns was similar between the two groups; however, superior reduction in the fracture gap of the posterior wall was observed in the SI group, as revealed by axial and coronal computed tomography scans. CONCLUSIONS: A simultaneous ventral and dorsal approach through the pararectus and the modified Gibson approach confer clinical advantages in reducing the fracture gap, surgical time, and intraoperative blood loss when managing acetabular fractures involving both columns and a displaced posterior wall. Therefore, these surgical approaches may be considered to be optimal for achieving satisfactory reduction quality in such fractures.

Higher pelvic incidence values are a risk factor for trans-iliac trans-sacral screw malposition in sacroiliac complex fracture treatment.

BACKGROUND: Percutaneous iliosacral (IS) screw fixation and trans-iliac trans-sacral (TITS) screw fixation are clinically effective treatments of posterior pelvic sacroiliac fractures. In order to accurately assess the sacrum position relative to the pelvis, pelvic incidence (PI) is a commonly utilized radiographic parameter in sagittal view. This study aimed to investigate and compare the surgical outcomes and radiographic parameters of IS or TITS screw fixations for the treatment of posterior sacroiliac complex fractures with different PI values. MATERIALS AND METHODS: The data on patients with posterior pelvic sacroiliac fractures who underwent percutaneous IS or TITS screw fixations, or both, at a single level I trauma center between January 2017 and June 2020 were reviewed. We documented the patient characteristics and fracture types, reviewed surgical records, and measured the radiographic parameters via plain films and multi-planar computed tomography (mpCT) images. Radiographic variations in PI, sacral slope, pelvic tilt, sacral dysmorphism, pelvic ring reduction quality, screw deviation angles, screw malposition grading, and iatrogenic complications were documented and analyzed. RESULTS: A total of 85 patients were included, and 65 IS and 70 TITS screws were accounted for. Patients were divided into two groups according to screw fixation method and further divided into four sub-groups based on baseline PI values. The PI cutoff values were 49.85° and 48.05° in the IS and TITS screw groups, respectively, according to receiver operating characteristic analysis and Youden's J statistic. Smaller PI values were significantly correlated with sacral dysmorphism (p = 0.027 and 0.003 in the IS and TITS screw groups, respectively). Patients with larger PI values were at a significantly increased risk of screw malposition in the TITS screw group (p = 0.049), with no association in the IS screw group. Logistic regression confirmed that a larger PI value was a significant risk factor for screw malposition in the TITS screw group (p = 0.010). The post-operative outcomes improved from poor/fair (at 6 months) to good/average (at 12 months) based on the Postel Merle d'Aubigné and Majeed scores, with no significant differences between subgroups. CONCLUSIONS: Both percutaneous IS and TITS screw fixations are safe and effective treatments for posterior pelvic sacroiliac fractures. Due to the higher risk of screw malposition in patients with larger PI values, it is crucial to identify potential patients at risk when performing TITS screw fixation surgery. LEVEL OF EVIDENCE: Level III.

Incidence of deep vein thrombosis and symptomatic pulmonary embolism in Taiwanese patients with pelvic and/or acetabular fractures: a retrospective study.

Venous thromboembolism (VTE) is common in patients with trauma, and thromboprophylaxis has been advocated. However, conflicting results regarding VTE rates in the Asian population following orthopaedic procedures have been presented. We aimed to investigate the VTE incidence in Taiwanese patients with pelvic and/or acetabular fractures and identify the associated risk factors. We included 402 patients who underwent surgery for pelvic and/or acetabular fractures. All patients received mechanical thromboprophylaxis with graduated compression stockings. Duplex scanning was performed postoperatively or during follow-up when signs or symptoms of deep vein thrombosis (DVT) developed. Variables with a significance level of ≤ 0.1 in the univariate analyses were introduced into the multivariate logistic regression analysis to identify DVT risk factors. The overall DVT and symptomatic pulmonary embolism (PE) rate was 3.48% (14/402 patients). Among patients with DVT, 46.1% were asymptomatic. Patients with VTE were significantly older than those without. Multivariate logistic regression analysis revealed that age was a VTE risk factor. The incidence of DVT and symptomatic PE in our cohort was low. Advanced age was a risk factor for VTE. These findings could help clinicians develop appropriate prevention and treatment strategies for VTE in Taiwanese patients with pelvic and/or acetabular fractures.

The double-plate fixation technique prevents varus collapse in AO type C3 supra-intercondylar fracture of the distal femur.

INTRODUCTION: Varus collapse followed by osteosynthesis for distal femoral fractures with conventional implants has been well documented but is seldom mentioned in fractures managed with locking plates. The purpose of this study was to assess the incidence of varus collapse after treating complex supra-intercondylar fractures of the distal femur (AO type C3) using a Single Plate (SP) or Double Plate (DP) fixation technique. MATERIALS AND METHODS: We retrospectively reviewed 357 patients with distal femoral fractures who were treated at our hospital between 2006 and 2017. After excluding cases of infection, malignancy, periprosthetic fracture, revision surgery, pediatric fracture, and extra-articular fracture, 54 patients were included in the study. All demographic data and radiological and clinical outcomes were reviewed and analyzed. RESULTS: There were 54 patients enrolled into this study with age from 15 to 85 years old (mean 41.6, SD = 19.9), and 32 of them were open fractures (59%). The patients were further divided into either an SP (n = 15) or a DP group (n = 39). Demographics, including age, sex, injury severity score, and open fracture type, were all compatible between the two groups. The overall nonunion rate was 25.9% (n = 14; 6 from the SP and 8 from the DP group; p = 0.175). The varus collapse rate was 9.3% (n = 5; 4 from the SP and 1 from the DP group (p = 0.018). CONCLUSIONS: The varus collapse rate after osteosynthesis with a single lateral locking plate could be as high as 26.7% in AO type C3 fractures of the distal femur, which would be decreased to 2.6% by adding a medial buttress plate. Surgeons should consider DP fixation to avoid varus collapse in severely comminuted complete intra-articular fractures of the distal femur.

Distraction Gap Needed for Safe Central Compartment Access in Hip Arthroscopy.

BACKGROUND: Sufficient distraction of the hip is the key to a safe central compartment (CC) approach in hip arthroscopy. However, an adequate distraction gap has not been scientifically identified. PURPOSE: To determine the sufficient amount of distraction that could predict a successful CC access as well as to identify the risk factors for a failed or difficult CC access. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: All patients who underwent hip arthroscopy by a single surgeon between January 2018 and April 2019 were prospectively enrolled. We analyzed gaps of the hip on 4 C-arm fluoroscopic images: nondistraction, preoperative manual traction, preoperative maximal traction (without distension), and intraoperative maximal traction (at the end of CC procedures in a successful CC approach or after peripheral compartment procedures in a failed or difficult CC approach). A failed CC approach was defined as failure in introducing the anterolateral portal to the CC under arthroscopic control; a difficult CC approach was defined as the presence of an incomplete diagnostic round in the CC because of a small distraction. The amount of distraction was evaluated by the ratio of the distracted gap to the undistracted gap. Patients were classified into the successful CC access group (group 1) and the failed/difficult CC access group (group 2). The amount of distraction, demographic characteristics, and preoperative radiographic parameters were compared between the groups. RESULTS: A total of 240 patients were included in this study. Group 1 consisted of 205 patients (113 males and 92 females; mean ± SD age, 34.5 ± 11.4 years), and group 2 consisted of 35 patients (27 males and 8 females; age, 32.5 ± 11.2 years). The preoperative joint space width was not significantly different between group 1 (mean ± SD, 3.89 ± 0.83 mm) and group 2 (3.68 ± 0.68 mm). The ratio of the amount of distraction at lateral gaps under all traction conditions was significantly greater in group 1 compared with group 2 (1.50 ± 0.54 vs 1.26 ± 0.35, respectively, under preoperative manual traction; 2.84 ± 0.76 vs 2.03 ± 0.63 under preoperative maximal traction; 3.36 ± 0.96 vs 2.50 ± 0.79 under intraoperative maximal traction). An increase of the lateral gap by >2.2 times (P < .001) under preoperative maximal traction and by >2.7 times (P < .001) under intraoperative maximal traction could predict successful CC access. Male sex (odds ratio [OR], 2.94; P = .017) and increased lateral center-edge angle (OR, 1.08 for every 1° increase; P = .004) were significant risk factors for failed/difficult CC access. CONCLUSION: An increase of the lateral gap by >2.2 times during an unsterile traction test without joint distension could predict successful CC access. Male sex and increased lateral center-edge angle were risk factors for a failed or difficult CC access.

Three-year functional outcome after open pelvic fracture treatment: a retrospective case series from a level I trauma center.

PURPOSE: Open pelvic fractures have high mortality rates, and survivors may have ongoing functional deficits from severe trauma and invasive life-saving procedures. However, there are limited reports regarding the functional status evaluation following open pelvic fractures. We aimed to report the treatment experiences and short-term functional outcomes of patients with open pelvic fractures. METHODS: We retrospectively reviewed the data of 19 consecutive patients with pelvic fractures who underwent treatment at a single institute between January 2014 and June 2018. The resuscitation protocol, osteosynthesis strategy, reduction quality of the pelvic ring, and functional outcomes were analyzed. RESULTS: The incidence and mortality rates in patients with open pelvic fractures were 4.9 and 21.6%, respectively. Ten, one, and seven of the open wounds related to the pelvic fractures were located in Faringer zones I, II, and III, respectively. Fractures of four patients were categorized as classes 1 and 2, and those of 11 patients as class 3, according to the Jones-Powell classification. Eleven of 19 (57.9%) and 9 of 19 (47.5%) revealed excellent reduction quality by Matta/Torenetta and Lefaivre criteria, respectively. The Merle d'Aubigné score improved at each evaluation but stagnated after 24 months. The Majeed hip score also improved at the 12-month evaluation but the improvement stopped thereafter. At a 3-year follow-up, the patients with excellent reduction of the pelvic ring showed the highest functional performances. CONCLUSION: Improvements in functional status of patients with open pelvic fractures can be anticipated based on the reduction quality of the pelvis ring.

Pararectus approach to the AO B2.2 pelvic fracture: early functional and radiological outcomes.

PURPOSE: The pararectus approach is used to treat acetabular fractures; however, it remains unclear whether it can be used to treat pelvic fractures. This study aimed to examine the outcomes of patients with a pelvic ring fracture treated with this approach. METHODS: Seven patients with AO B2.2 pelvic fractures treated with the pararectus approach were included. Patients' pain was assessed pre- and postoperatively with a numerical rating scale. Radiological evaluations included inlet and outlet ratios and pelvic symmetry. Functional outcomes, including Merle d'Aubigné and Majeed scores, were also recorded for 12 months. RESULTS: One patient experienced obturator nerve neuropraxia. Pain scores ranged from 2.3-8.0 to 2.0-3.1 points before and after surgery, respectively. Radiological findings revealed satisfactory outcomes. The maximal gap of the affected ilium reduced from 8.6-20.2 to 0-3.4 mm, from 6.8-17.9 to 0-4.4 mm, and from 3.7-20.3 to 0-3.2 mm in the axial, sagittal, and coronal views, respectively. Based on multiple evaluations, functional outcomes were improved for all patients. CONCLUSION: The pararectus approach can be used safely and satisfactorily to treat AO B 2.2 pelvic fractures.

Causes of Increased Use of Closed Reduction and Internal Fixation for High-Energy-Related Traumatic Sacral Fractures.

BACKGROUND: Reasons for the increased use of closed reduction and internal fixation (CRIF) for traumatic sacral fractures (SFs) are unclear in the literature. Therefore, we aimed to report the annual changes in the number of patients, mechanisms of injury, fracture patterns, and fixation methods. METHODS: In this retrospective study, we extracted data of 271 patients (mean age, 37.5 years) from the trauma register over an 8-year period. Annual records regarding the number of patients, injury mechanisms, fracture types, and treatment options were statistically analyzed to examine the interactions among these factors. RESULTS: The number of patients with SFs increased significantly each year. The rate of admission to the intensive care unit after resuscitation was high (64.9%). Arbeitsgemeinschaft für Osteosynthesefragen (AO) type C pelvic ring injury (PRI), Dennis zone II injury, Roy-Camille type 2 injury, and U/H-type injury were the most common fracture types. Trans-iliac trans-sacral screws were mainly used in AO type B PRI, and their use significantly increased each year. For AO type C PRI, open reduction and internal fixation (ORIF) with rigid fixation was the main treatment, and the use of CRIF with iliosacral screws decreased each year. Stepwise statistical analysis revealed that the increase in AO type B PRI and ORIF for anterior PRI were the factors contributing to the increased use of CRIF for SFs. CONCLUSIONS: While the use of osteosynthesis for SFs is increasing, an increased use of CRIF for traumatic SFs has also been observed in clinical practice. This increase can be attributed to the increase in AO type B PRIs and ORIF for anterior PRIs.

The posterior capsule is distended in dysplastic hips, but the anterior capsule is not.

PURPOSE: In the setting of acetabular dysplasia, the increased translational motion of the femur may damage the labrum and cartilage, as well as stretch the capsule. The purpose of the study was to investigate the relationship between the acetabular coverage and the capsular stiffness by assessing the distension of anterior and posterior joint recesses on the hip computed tomography arthrography. METHODS: One hundred thirty-three patients (138 hips) with a median age of 36 years (range 18-50 years) who received the computed tomography arthrography for evaluation of nonarthritic hip pain in our institute between 2015 and 2017 were retrospectively reviewed. The maximal distance between the anterior/posterior capsule and the anterior femoral head-neck junction/posterior femoral head on the axial imaging of computed tomography arthrography was defined as the width of anterior/posterior joint recess. The width of anterior/posterior joint recess was adjusted with the diameter of the femoral head and was then compared between acetabular dysplasia (lateral center-edge angle < 25°), normal acetabulum (lateral center-edge angle between 25 and 39°), and deep acetabulum (lateral center-edge angle > 39°). In addition, the standard univariate linear regression analysis was used to investigate the relationship between the adjusted width of anterior/posterior joint recess and anterior/posterior coverage of the hip, determined by the anterior/posterior wall index. RESULTS: The adjusted width of posterior joint recess was significantly greater in the acetabular dysplasia group than the normal acetabulum and deep acetabulum groups (p < 0.01 and p = 0.02, respectively). There was no significant difference of the adjusted width of anterior joint recess between the groups (n.s.). The adjusted width of posterior joint recess had a significant but weak negative correlation with the anterior wall index (r = - 0.25, p < 0.001), and no correlation with the posterior wall index (r = - 0.0004, n.s.). There was no significant correlation between the adjusted width of anterior joint recess and the anterior/posterior wall index (r = 0.05, n.s./r = 0.07, n.s.). CONCLUSIONS: The distension of posterior capsule on the computed tomography arthrography was significantly greater in acetabular dysplasia. In addition, there was a significant but weak negative correlation between the distension of posterior capsule and the anterior coverage of the hip. It indicated a looser posterior capsule was observed in a dysplastic hip. The relevance of posterior capsular laxity to clinical outcomes warrants further investigation. Given the fact that the distension of anterior capsule was not significantly higher in acetabular dysplasia, the need of anterior capsular plication in a dysplastic hip should be carefully evaluated. LEVEL OF EVIDENCE: Level III.

Simultaneous reduction and fixation of concomitant acetabular fracture and ipsilateral sacroiliac joint injury through the pararectus approach: a technical report and early radiological outcome.

PURPOSE: Osteosynthesis for acetabular fractures with ipsilateral sacroiliac joint (SIJ) injuries remains challenging for orthopedic surgeons, despite the evolution of surgical approaches, such as the pararectus approach, and treatment sequences. The study aimed to describe the details of the treatment of acetabular fracture with ipsilateral SIJ injury by the pararectus approach and to report its surgical outcomes. METHODS: We retrospectively assessed patients with acetabular fractures and ipsilateral SIJ injuries undergoing osteosynthesis by the pararectus approach over a three-year period. Evaluation parameters of the quality of reduction of both acetabulum and pelvis injuries were, among others, Matta's criteria, Lefaivre's criteria, inlet/outlet ratios, and maximal gap measured on computed tomography (CT) scans. RESULTS: Ten patients (seven men and three women) were enrolled. Pelvic ring injuries classified as AO B2.3 and acetabular fractures involving two columns were the most common fractures, accounting for 70% and 60%, respectively. Radiological evaluation for pelvic ring injury revealed three excellent and seven good results according to Matta's criteria, as well as five excellent, three good, and one fair results according to Lefaivre's criteria. Inlet and outlet ratios were between 0.84-1.06 and 0.93-1.60, respectively. The distance of the sacroiliac joints significantly improved postoperatively in both axial and coronal views (P = 0.002). Further, the maximal articular gap and step-off of acetabular fractures on axial, coronal, and sagittal view CT scans showed statistically significant improvements after osteosynthesis. CONCLUSION: Simultaneous reduction and fixation of acetabular fractures with ipsilateral SIJ injuries using the pararectus approach achieved satisfactory radiological outcomes. LEVEL OF EVIDENCE: IV. TRIAL REGISTRATION: Retrospectively registered.

Intentional Fallers with Complex Pelvic and Acetabular Fractures Do Not Have worse Radiological and Functional Outcomes than Accidental Fallers.

Individuals who fall from heights of ≥6 m can suffer from complex pelvic and acetabular fractures. The extent to which an intentional fall correlates with prognosis and outcome after osteosynthesis is unclear. Therefore, we aimed to investigate the clinical outcomes of fallers with pelvic and acetabular fractures after osteosynthesis and compare the radiological and functional outcomes between intentional and accidental fallers. We retrospectively reviewed 49 fallers who fell from heights of ≥6 m, developed pelvic and acetabular fractures, survived after resuscitation, and completed surgical treatment between 2014 and 2017. Fallers were divided into intentional and accidental fallers. Sixteen patients were intentional fallers, whereas the rest of the patients were accidental fallers. Psychiatric counseling was provided to each of the intentional fallers during follow-up. All intentional fallers had preexisting mental disorders, and the most common diagnosis was adjustment disorder. The group of intentional fallers predominantly comprised females that had a higher injury and new injury severity scores and longer hospital stays. However, early loss of fixation (<3 months) and functional outcomes (Merle d'Aubigné and Majeed hip scores at 6- and 12-month follow-ups) did not significantly differ between intentional and accidental fallers. We found that intentional fallers with pelvic and acetabular fractures may have more severe combined injuries compared to accidental fallers. However, the radiological and functional outcomes of the intentional fallers after osteosynthesis were not inferior to those of the accidental fallers with the implementation of well-designed surgical protocols and individualized physical and mental rehabilitation programs.

Percutaneous iliosacral screw and trans-iliac trans-sacral screw with single C-arm fluoroscope intensifier is a safe treatment for pelvic ring injuries.

To elucidate the accuracy, efficacy, and safety of percutaneous iliosacral screw (ISS) and trans-iliac trans-sacral screw (TITS) insertion using a single C-arm fluoroscopy intensifier. Additionally, the potential risk factors that might cause mal-positioned screws were identified. Patients with pelvic ring injuries who underwent percutaneous screw fixation in a single medical institute were divided into an ISS group (n = 59) and a TITS group (n = 62) and assessed. The angles deviated from ideal orientation (ADIO) of the implanted screw were measured, and potential risk factors for mal-positioned screws were analyzed. Overall, the reduction quality of the pelvic ring was good or excellent in 70 patients (82.4%) by Matta's criteria and in 48 patients (56.5%) by Lefaivre's criteria. ADIO measurements of the ISS and TITS groups via multi-planar computed tomography were 9.16° ± 6.97° and 3.09° ± 2.8° in the axial view, respectively, and 5.92° ± 3.65° and 2.10° ± 2.01° in the coronal view, respectively. Univariate statistical analysis revealed body mass index as the single potential risk factor of mal-positioned screws. With careful preoperative planning and intraoperative preparations, placing ISS and TITS under the guidance of single C-arm fluoroscopy intensifier is a reliable and safe technique. Caution should be exercised when performing this procedure in patients with a high body mass index.

Preoperative Alpha Angles Can Predict Severity of Acetabular Rim Chondral Damage in Symptomatic Cam-Type Femoroacetabular Impingement: A Prospective Observatory Study.

PURPOSE: To identify the relationship between the alpha angle and the severity of chondrolabral separation as well as acetabular rim chondral damage in symptomatic cam-type femoroacetabular impingement (FAI) with or without focal pincer-type FAI. METHODS: Patients who received hip arthroscopy under the diagnosis of symptomatic cam-type FAI between January 2018 and August 2018 were identified in a prospectively collected database. Patients were excluded if preoperative lateral center-edge angle <25°, lateral center-edge angle ≥40°, Tönnis grade >1, with previous surgery on the affected hip, or with concomitant synovial disease. The chondrolabral junction was classified into intact chondrolabral junction, stable chondrolabral separation and unstable chondrolabral separation. The classification of acetabular rim chondral damage was modified from the MAHORN (Multicenter Arthroscopy of the Hip Outcomes Research Network) classification: normal/softening, bubble, pocket, flap, and exposed bone. The relationship between the hip morphology and severity of chondrolabral junction and acetabular rim chondral damage was assessed. RESULTS: A total of 71 patients with the mean age of 33.2 ± 11.0 years were included. Preoperative alpha angles on anteroposterior (AP) or Lauenstein view positively correlated with the severity of acetabular rim chondral damage (P = .028 and P = .016, respectively). A significant increment of the alpha angle between 2 consecutive grades of acetabular rim chondral damage was 7.1° (P = .001) on AP view and 5.2° on Lauenstein view (P = .001). The cut-off values for predicting advanced acetabular rim chondral damage (pocket, flap or bony exposure) were an AP alpha angle of 70° (P = .025) and a Lauenstein alpha angle of 57° (P = .003). There was no significant association between the alpha angle and the severity of chondrolabral separation. CONCLUSIONS: In patients with symptomatic cam-type FAI with or without focal pincer-type FAI, greater preoperative alpha angles on AP and Lauenstein views can predict more severe acetabular chondral damage. LEVEL OF EVIDENCE: Level III.

Matta's criteria may be useful for evaluating and predicting the reduction quality of simultaneous acetabular and ipsilateral pelvic ring fractures.

BACKGROUND: Although the incidence, types, and radiological outcomes of simultaneous ipsilateral pelvic ring and acetabular fractures have been reported, there have been no reports on factors that may affect the quality of acetabular fracture reduction. Here, we evaluate the radiological outcomes of patients treated for simultaneous ipsilateral pelvic and acetabular fractures and analyze the factors that affect the quality of acetabular fracture reduction. METHODS: We conducted a retrospective review of patients treated for simultaneous ipsilateral pelvic ring and acetabular fractures between 2016 and 2020. Factors that may predict inadequate reduction of the acetabular fracture were analyzed. RESULTS: Data from 27 hips of 26 patients were collected. AO B2.2 and anterior columnar fractures were the most common types of pelvic ring and acetabular fractures, respectively. Univariate analysis revealed that Matta's criteria for pelvic ring fracture may be useful for predicting fair to poor quality of acetabular fracture reduction on X-rays. Furthermore, associated fractures identified by Letournel's classification system on computed tomography may be predictive of greater step-offs. CONCLUSIONS: Associated fractures identified via Letournel's classification may contribute to inadequate reduction of acetabular fractures. Matta's criteria for pelvic ring fractures may also be useful for predicting the risk of inadequate reduction of the acetabulum on X-ray scans. These findings may be assessed intraoperatively by fluoroscopy before beginning osteosynthesis for acetabular fractures.

Predictors of Acute Mortality After Open Pelvic Fracture: Experience From 37 Patients From A Level I Trauma Center.

BACKGROUND: Open pelvic fractures are caused by high-energy traumas and are accompanied by organ injuries. Despite improvements in pre-hospital care, the acute mortality rate following open pelvic fractures remains high. This study aimed to report experiences in managing open pelvic fractures, identify potential independent predictors that contribute to acute mortality in such patients, and generate a scoring formula to predict mortality rate. METHODS: Open pelvic fracture patients managed during a 42-month period were retrospectively studied. Logistic regression analysis was used to determine predictors of acute mortality. Using the Youden index, threshold values of predictors were selected. Significant predictors were weighted to create a scoring formula. The area under the curve (AUC) was tested in this specific group. RESULTS: The incidence of open pelvic fractures in all pelvic fractures was 4.9% (37/772), and the overall mortality rate was 21.6% (8/37). All the successfully resuscitated patients entered the reconstruction stage survived and underwent the complete treatment course. Univariate and multivariate logistic regression analyses revealed that the revised trauma score (RTS) was the single independent predictor of acute mortality. A scoring formula was generated following the statistical analysis. The probability of mortality was 0% and 100% when the score was above and below -2, respectively. This model predicted mortality with an AUC of 0.948 (95% confidence interval 0.881-1.000, P < 0.01). CONCLUSION: The RTS may be a potential predictor of acute mortality in open pelvic fracture patients. Further work would be required to validate the clinical efficacy of the generated scoring formula.

Symptomatic pulmonary embolism following hip fracture: A nationwide study.

INTRODUCTION: This study evaluated the incidence of symptomatic pulmonary embolism (PE), subsequent mortality, risk factors, and the effects of pharmacological thromboprophylactic intervention following hip fracture surgery in Taiwan. MATERIALS AND METHODS: A nationwide study was conducted from February 2004 to September 2013. Hip fracture patients were placed into two groups: without symptomatic PE (control group) and with symptomatic PE (PE group). We analyzed the incidence of and risk factors for symptomatic PE, post-operative mortality rate, and effects of pharmacological thromboprophylactic intervention. RESULTS: We identified 165,748 hip fracture patients. The 3-month cumulative incidence of post-operative symptomatic PE was 0.24% (n = 392). The cumulative 1-, 3-, and 6-month mortality rates were significantly higher in the PE group (16.1%, 23.0%, and 28.6%, respectively) than in the controls (3.3%, 6.7%, and 10.2%, respectively). Increased risk of post-operative symptomatic PE was associated with prior history of PE (adjusted odds ratio [OR], 40.00; 95% CI, 24.75-64.67; P < 0.001), female sex (adjusted OR, 1.33; 95% CI, 1.07-1.65; P = 0.009), older age (>75 years) (adjusted OR, 1.51; 95% CI, 1.20-1.91; P < 0.001), and hemiarthroplasty (adjusted OR, 1.23; 95% CI, 1.01-1.51; P < 0.043). Pharmacological thromboprophylaxis significantly reduced the incidence of post-operative PE (adjusted hazard ratio, 4.54; 95% CI, 2.08-9.88; P < 0.001). CONCLUSIONS: The incidence of symptomatic PE after hip fracture surgery was not low in Asian patients, and PE significantly decreased patient survival rates. Some groups were at higher risk for PE; in these instances, thromboprophylaxis, prompt diagnosis, and subsequent intervention are advised.

The influence of spinopelvic parameters on adjacent-segment degeneration after short spinal fusion for degenerative spondylolisthesis.

OBJECTIVE: Spinopelvic parameters, such as the pelvic incidence (PI) angle, sacral slope angle, and pelvic tilt angle, are important anatomical indices for determining the sagittal curvature of the spine and the individual variability of the lumbar lordosis (LL) curve. The aim of this study was to investigate the influence of spinopelvic parameters and LL on adjacent-segment degeneration (ASD) after short lumbar and lumbosacral fusion for single-level degenerative spondylolisthesis. METHODS: The authors retrospectively reviewed the records of all short lumbar and lumbosacral fusion surgeries performed between August 2003 and July 2010 for single-level degenerative spondylolisthesis in their orthopedic department. RESULTS: A total of 30 patients (21 women and 9 men, mean age 64 years) with ASD after lower lumbar or lumbosacral fusion surgery comprised the study group. Thirty matched patients (21 women and 9 men, mean age 63 years) without ASD comprised the control group, according to the following matching criteria: same diagnosis on admission, similar pathologic level (≤ 1 level difference), similar sex, and age. The average follow-up was 6.8 years (range 5-8 years). The spinopelvic parameters had no significant influence on ASD after short spinal fusion. CONCLUSIONS: Neither the spinopelvic parameters nor a mismatch of PI and LL were significant factors responsible for ASD after short spinal fusion due to single-level degenerative spondylolisthesis.

Identification of neuraminidase inhibitors against dual H274Y/I222R mutant strains.

Influenza is an annual seasonal epidemic that has continually drawn public attentions, due to the potential death toll and drug resistance. Neuraminidase, which is essential for the spread of influenza virus, has been regarded as a valid target for the treatment of influenza infection. Although neuraminidase drugs have been developed, they are susceptible to drug-resistant mutations in the sialic-binding site. In this study, we established computational models (site-moiety maps) of H1N1 and H5N1 to determine properties of the 150-cavity, which is adjacent to the drug-binding site. The models reveal that hydrogen-bonding interactions with residues R118, D151, and R156 and van der Waals interactions with residues Q136, D151, and T439 are important for identifying 150-cavitiy inhibitors. Based on the models, we discovered three new inhibitors with IC50 values <10 µM that occupies both the 150-cavity and sialic sites. The experimental results identified inhibitors with similar activities against both wild-type and dual H274Y/I222R mutant neuraminidases and showed little cytotoxic effects. Furthermore, we identified three new inhibitors situated at the sialic-binding site with inhibitory effects for normal neuraminidase, but lowered effects for mutant strains. The results suggest that the new inhibitors can be used as a starting point to combat drug-resistant strains.