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.

A combination of the K-L and S-P approaches for treating acetabular posterior wall factures accompanied by femoral head fractures with open reduction and internal fixation.

BACKGROUND: In clinical practice, acetabular posterior wall fracture combined with femoral head fracture is rare. However, with the increasing number of engineering and traffic accidents, such fractures, have increased significantly in recent years. This paper aims to explore the clinical efficiency of the Kocher-Langenbeck (K-L) and Smith-Petersen (S-P) combined approaches for open reduction and internal fixation (ORIF) of acetabular posterior wall fractures accompanied by femoral head fractures (Pipkin type IV fractures). METHODS: A retrospective study was conducted on 8 patients who underwent open reduction and internal fixation (ORIF) of Pipkin type IV fractures through the K-L combined with S-P approach in our hospital from January 2015 to January 2020. All 8 patients were successfully operated on without serious complications, such as important blood vessel and nerve damage, with an operation time of 143.8 ± 44.38 min and intraoperative blood loss of 225 ± 70.71 ml. Perioperative data were recorded. The Harris score was used to evaluate the clinical effect. Fracture reduction quality was evaluated according to the Matta radiological standard. The grade of ectopic ossification was evaluated by the Brooker grading method, and the stage of femoral head necrosis was evaluated by Ficat-Arlet staging. RESULTS: The Harris score increased significantly from 57.38 ± 4.779 at 3 months, to 76.13 ± 3.682 at 6 months, 88.25 ± 3.495 at 12 months, and 92.13 ± 2.232 at 36 months postoperatively. After statistical analysis, compared with the previous observation time point, the data comparison differences between the groups were statistically significant. P < 0.001, P < 0.001, P < 0.05). By the time of the latest follow-up, 6 of the 8 patients had recovered to the level of pre-injury sports capacity. In contrast, the other 2 patients remained below the level of pre-injury sports capacity. In terms of imaging evaluation, the quality of fracture reduction on radiographs was graded as excellent in 6 patients and good in 2 patients according to Matta's criteria. At the last follow-up, no heterotopic ossification or femoral head necrosis was found in of all the images. In addition, the hip joint space was normal in 6 cases, mildly narrowed in 1 case, and clearly narrowed in 1 case. CONCLUSIONS: The K-L combined with S-P approach provides effective exposure for the reduction and fixation of Pipkin type IV fractures and achieves satisfactory clinical outcomes.

Posterior wall acetabular fracture in a 13-year-old boy treated by open reduction and mini-plate internal fixation: long-term follow-up of 17 years.

BACKGROUND: Acetabular fractures are uncommon in children and adolescents, mainly because of predominant cartilaginous component and strong surrounding ligaments. Although acetabular fractures at this age can lead to significant disability, there is no consensus regarding management, which continues to be controversial. Particularly, long-term outcome after operative management has not been evaluated. CASE PRESENTATION: We report a case of a 13-year-old boy skeletally immature who presented with an isolated acetabular fracture involving the posterior wall secondary to a traumatic hip dislocation. A Kocher-Langenbeck approach with a surgical luxation of the hip was used for reduction and mini-plate internal fixation of the fracture. Long-term (17-year) follow-up showed a good clinical outcome and a good congruence of the. The patient has bilateral beginning osteoarthritis due to a cam configuration of both hips CONCLUSION: We describe a case of successful operative management of an acetabulum fracture in a skelettaly immature child with a long-term follow-up. Aggressive management of this rare type of fractures may lead to durable positive outcome.

Marginal impaction in complex posterior wall acetabular fractures: role of allograft and mid-term results.

OBJECTIVE: To evaluate the functional and radiological outcome of complex posterior wall acetabular fractures with marginal impaction treated with cancellous allograft and internal fixation. METHODS: A total of 16 patients with marginal impaction on pre-operative CT scan, who underwent internal fixation and allograft were analysed. Mean follow-up was 28 months (range 24-42). The mean age was 46.5 years (range 22-71). Out of 16 patients, 8 were AO A1.2- and 8 were AO A1.3-type fractures. Functional evaluation was performed using modified Merle d'Aubigné and Postel scores and radiological evaluation by Matta's criteria for quality of initial reduction and final outcome. RESULTS: The quality of reduction was anatomical in 12 patients (75%) and imperfect in 4 patients (25%). The radiological outcome at final follow-up was excellent in 9 (56.25%), good in 5 (31.25%) and fair in 2 patients (12.5%). None of the patients had a secondary loss of reduction at final follow-up. Functional outcome was excellent in 2 (12.5%), good in 8 (50%) and fair in 6 patients (37.5%). CONCLUSION: The use of cancellous allograft to fill the bone void provides good mechanical stability without any secondary loss of reduction. This surgical technique seems to be effective and safe in treating comminuted posterior wall fractures with marginal impaction without any donor site complications and other disadvantages of synthetic bone graft materials.

Outcomes are equivalent for two-column acetabular fractures either with or without posterior-wall fractures.

INTRODUCTION: It is likely that posterior-wall involvement in association with two-column fractures plays a pivotal role in outcomes because of the potential for hip instability if it is not anatomically reduced and fixed. Uncertainty remains about how this fracture is best treated, especially regarding how posterior-wall involvement may affect functional results. MATERIALS AND METHODS: To better understand the role that posterior-wall involvement may play in determining functional results, we compared data for outcomes for patients with posterior-wall involvement and for those without in a consecutive series of two-column fractures. Between 2000 and 2013, 42 patients who underwent surgical treatment for two-column acetabular fractures were evaluated after a minimum follow-up period of 1 year. Data were prospectively collected and retrospectively evaluated. Of the 42 patients, 25 had only a two-column fracture (group 1) and 17 had a two-column fracture with posterior-wall involvement (group 2). RESULTS: There were no differences between groups in terms of reduction accuracy, radiographic results, clinical results, or complication rates. All hips in patients with internal fixation for the associated posterior-wall fracture had anatomical reduction. At the latest follow-up evaluation, three patients from group 1 (without posterior-wall involvement) and three patients from group 2 (with posterior-wall involvement) had undergone total hip arthroplasty. CONCLUSION: These results suggest that a posterior-wall fracture in a two-column fracture does not compromise functional outcomes when the treatment algorithm discussed here is followed.

Modified one third tubular plate (spring plate) augmented with reconstruction plates for treatment of comminuted posterior wall acetabular fractures, Short to midterm outcomes of 24 patients.

The most common form of acetabular fracture is believed to be the posterior wall; its incidence ranges from 25% to 47%. Managing such fractures has been difficult in the past and until recently. To obtain a favorable functional outcome, an accurate diagnosis and a well-executed treatment strategy are essential. Objective: To evaluate the clinical and functional outcomes of employing a spring plate augmented by a traditional 3.5 mm reconstruction plate for the treatment of comminuted posterior wall acetabular fractures. Patients and Methods: A prospective case series was performed on 24 patients with comminuted fractures of the posterior wall. After an average of 6 days, the patients underwent surgery. Eighteen patients were fixed with one spring plate, six patients were fixed with two spring plates, and all were reinforced with a 3.5-mm reconstruction plate. Each case was followed once every three months until the fracture healed and then regularly every six months thereafter. Results: There were 21 men and 3 women. The average follow-up period was 14 months, and the median age was 34.5 years. The main reason for injuries was motor vehicle collisions. The mean operation time was 107.5 min. The clinical results were evaluated by the MAP and m HHS, and the means were 10.2 (5-12) and 86 (64-96), respectively. Only two patients developed avascular necrosis and were treated by total hip replacement, another three (12.5%) had mild arthritis. Conclusion: Comminuted acetabulum posterior wall fractures can be stabilized with spring plates. It could be used in conjunction with the primary reconstruction plate as a viable alternative for stable and anatomical reduction. High patient satisfaction and good functional results make this approach effective.

Which implant is better for the fixation of posterior wall acetabular fractures: A conventional reconstruction plate or a brand-new calcaneal plate?

BACKGROUND: Increased posterior wall acetabular fractures among older adults, require precise treatment to restore stability to the joint, lower the risk of degenerative arthritis, and enhance overall functional recovery. The purpose of this study was to compare the fixation stability and mechanical characteristics of calcaneal buttress plate and conventional reconstruction plate under different loading condition. METHODS: Typical acetabular posterior wall fractures were created on twenty synthetic hemipelvis models. They were fixed with calcaneus plate and reconstruction plate. Dynamic and static tests were performed. Displacements of fracture line and stiffness were calculated. FINDINGS: After dynamic loading, calcaneus plate fixation has significantly less displacement than the reconstruction plate on the superior posterior wall. Under static loading condition, the calcaneus plate group has significantly less displacement than the reconstruction plate group on the inferior posterior part of the fracture. The average stiffness values of the calcaneus plate group and the reconstruction plate group were 265.16±53.98 N/mm and 167.48±36.87 N/mm, respectively and a statistically significant difference was found between the two groups. INTERPRETATION: The calcaneal plate group demonstrated better stability along the fracture line after dynamic and static loading conditions. Especially when the fragment was on the acetabulum's superior posterior, inferior posterior, and inferior rim, Calcaneal buttress plates offer biomechanically effective choices.

[Analysis of the therapeutic effect of trochanteric flip osteotomy combined with Kocher-Langenbeck approach for high acetabular posterior wall fracture].

OBJECTIVE: Evaluation of the clinical efficacy of f trochanteric flip osteotomy combined with Kocher-Langenbeck approach for high acetabular posterior wall fracture. METHODS: Between January 2020 and December 2022, 20 patients with high acetabular posterior wall fractures were retrospectively analyzed, including 12 males and 8 females, aged 18 to 75 years old. They were divided into two groups according to the different surgical methods. Ten patients were treated with greater trochanteric osteotomy combined with Kocher-Langenbeck approach as the observation group, including 5 males and 5 females, aged from 18 to 75 years old. Ten patients were treated with Kocher-Langenbeck approach alone as the control group, including 7 males and 3 females, aged from 18 to 71 years old. Matta reduction criteria were used to evaluate the reduction quality of the two groups, and Harris score was used to compare the hip function of the two groups at the latest follow-up. The operation time, blood loss and postoperative complications of the two groups were analyzed. RESULTS: All patients were followed up for 10 to 24 months. According to the Matta fracture reduction quality evaluation criteria, the observation group achieved anatomical reduction in 6 cases, satisfactory reduction in 3 cases, and unsatisfactory reduction in 1 case, while the control group only achieved anatomical reduction in 3 cases, satisfactory reduction in 3 cases, and unsatisfactory reduction in 4 cases. At the final follow-up, the Harris hip score ranged from 71.4 to 96.6 in the observation group and 65.3 to 94.5 in the control group. According to the results of Harris score. The hip joint function of the observation group was excellent in 6 cases, good in 3 cases, and fair in 1 case. The hip joint function of the control group was excellent in 2 cases, good in 3 cases, fair in 3 cases, and poor in 2 cases. In the observation group, the intraoperative blood loss ranged from 300 to 700 ml, and the operation duration ranged from 120 to 180 min;in the control group, the intraoperative blood loss ranged from 300 to 650 ml, and the operation duration ranged from 100 to 180 min. Complications in the observation group included 1 case of traumatic arthritis and 1 case of heterotopic ossification, while complications in the control group included 3 cases of traumatic arthritis, 3 cases of heterotopic ossification and 1 case of hip abduction weakness. CONCLUSION: Trochanteric flip osteotomy combined with the Kocher-Langenbeck approach significantly improved anatomical fracture reduction rates, enhanced excellent and good hip joint function outcomes, and reduced surgical complication incidence compared to the Kocher-Langenbeck approach alone. Clinical application of this combined approach is promising, although larger studies are needed for further validation.

[Virtual preoperative planning and 3D-printed templates for pre-contoured plates in treatment of acetabular posterior wall fractures].

OBJECTIVE: To evaluate the feasibility and accuracy of virtual preoperative planning and 3D-printed templates for pre-contoured plates for the treatment of posterior wall fractures of the acetabulum. METHODS: A retrospective analysis of 29 patients with posterior acetabular wall fractures treated between August 2017 and March 2021 were divided into 2 groups based on whether to use preoperative virtual planning and 3D printed template. In 3D-printing group, there were 14 patients, including 10 males and 4 females； aged from 21 to 53 years old；CT-based virtual surgical planning was done using Mimics and 3-Matic software and 3D-printed templates for pre-contoured plates were adopted. In conventional group, there were 15 patients, including 10 males and 5 females；aged from 19 to 55 years old；conventional method of intra-operative contouring to adapt the plate to the fracture region was adopted. Blood loss, surgical time, radiographic quality of reduction, and hip function were compared between groups. RESULTS: The difference in operation time and intraoperative blood loss was significant（P<0.05）. Twenty-three patients were followed up from 12 to 30 months, and the fractures in both groups healed with a healing time of 3 to 6 months. At the last follow-up, the Merle d'Aubign-Postel score of the 3D printed group was lower than that of the conventional group（P<0.05）, with no significant differences in walking ability, hip mobility and total score（P>0.05）. In 3D printing group, 6 cases were excellent, 5 cases were good, 3 cases were fair；in conventional group, 5 cases were excellent, 5 cases were good, 4 cases were fair, 1 case was worse；no significant difference between two groups（P>0.05）. CONCLUSION: Virtual preoperative planning and 3D-printed templates for pre-contoured plates can reduce operative time and the blood loss of surgery, improve the quality of reduction. This method is efficient, accurate and reliable to treat acetabular posterior wall fractures.

Anatomical Posterior Acetabular Plate Versus Conventional Reconstruction Plates for Acetabular Posterior Wall Fractures: A Comparative Study.

Background: Functional recovery following the surgical fixation of acetabular posterior wall fractures remains a challenge. This study compares outcomes of posterior wall fracture reconstruction using an anatomical posterior acetabular plate (APAP) versus conventional reconstruction plates. Methods: Forty patients with acetabular fractures involving the posterior wall or column underwent surgery, with 20 treated using APAPs (APAP group) and 20 with conventional pelvic reconstruction plates (control group). Baseline patient characteristics, intraoperative blood loss and time, reduction quality, postoperative function, and postoperative complications were compared using appropriate non-parametric statistical tests. A general linear model for repeated measures analysis of variance was employed to analyze trends in functional recovery. Results: No significant differences were observed in baseline characteristics. APAP significantly reduced surgical time by 40 min (186.5 ± 51.0 versus 225.0 ± 47.7, p =0.004) and blood loss (695 ± 393 versus 930 ± 609, p = 0.049) compared to conventional plates. At 3 and 6 months following surgery, the APAP group exhibited higher functional scores (modified Merle d'Aubigné scores 10 ± 1.8 versus 7.8 ± 1.4, p < 0.001; 13.4 ± 2.8 versus 10.1 ± 2.1, p = 0.001), converging with the control group by 12 months (modified Merle d'Aubigné scores 14.2 ± 2.6 versus 12.7 ± 2.6, p = 0.072; OHS 31.6 ± 12.3 versus 30.3 ± 10.1, p = 0.398). Radiologically, the APAP group demonstrated superior outcomes (p = 0.047). Complication and conversion rates to hip arthroplasty did not significantly differ between groups (10% versus 15%, p = 0.633). Conclusions: The use of an APAP in reconstructing the posterior acetabulum significantly reduces surgical time, decreases intraoperative blood loss, and leads to earlier functional recovery compared to conventional reconstruction plates. The APAP provides stable fixation of the posterior wall and ensures the durable maintenance of reduction, ultimately yielding favorable surgical outcomes.

Arthroscopic Reduction and Internal Fixation in Patients with Acetabular Posterior Wall Fractures.

Background: This study aimed to access the radiologic and clinical outcomes after arthroscopic reduction and internal fixation with screws in patients with posterior wall fractures of the acetabulum. Methods: From May 2013 to December 2019, 13 patients (11 men and 2 women) with posterior wall fractures of the acetabulum were treated with arthroscopic reduction and internal fixation with screws at two medical centers. The mean age at the index operation was 39 years (range, 22-58 years). The mean duration of follow-up was 23 months (range, 12-46 months). Clinical assessment was performed using the modified Merle d'Aubigné and Postel functional scoring system. The maximum displacement of acetabular or femoral head fragments detected on radiographs was used as radiographic results. Secondary osteoarthritis, osteonecrosis, or heterotrophic ossification was assessed at the latest follow-up. Results: Bony union was shown at 12 weeks of follow-up in all patients. The radiologic outcomes showed an anatomical reduction in 11 patients and a satisfactory reduction in 2 patients. The modified Merle d'Aubigné and Postel functional score was excellent in 7 patients, good in 5 patients, and fair in 1 patient. Two patients had transient pudendal nerve palsy after hip arthroscopy. However, no sciatic nerve palsy occurred. At the latest follow-up, there was no heterotopic ossification, osteonecrosis of the femoral head, or posttraumatic osteoarthritis. Conclusions: Arthroscopic reduction and internal fixation with cannulated screws can be good alternative options with good radiographic and clinical outcomes, convenient removal of intra-articular loose body, and low complication rates.

Outcomes of associated both-column acetabular fractures with and without a posterior wall fracture- A retrospective observational cohort study.

Aims & objectives: Our study sought to determine if posterior wall (PW) involvement in associated both-column acetabular fractures (ABCAFs) is associated with different clinical outcomes, primarily rate of conversion to total hip arthroplasty (THA), in comparison to ABCAFs with no PW involvement. Materials & methods: This retrospective observational cohort study was performed at two academic Level 1 trauma centers. Two study groups were identified. The first study group consisted of 18 patients who sustained an ABCAF with PW involvement (+PW). The second study group consisted of 26 patients who sustained an ABCAF with no PW involvement (-PW). All patients achieved a minimum 12-months of follow-up and/or received a THA conversion procedure at a time remote to their index open reduction internal fixation (ORIF) procedure. The primary outcome of this study was subsequent conversion to THA on the injured hip. The secondary outcome was the presence of post-operative pain at ≥6 months and/or complications. Results: No difference in rate of conversion to THA between + PW (n = 4, 22.2%) and -PW (n = 3, 11.5%) groups was demonstrated (p = 0.419). Similarly, no differences were seen between groups regarding complication rate (p = 0.814) and post-operative pain (p = 0.142). Conclusion: Involvement of the PW does not appear to create worse clinical outcomes in comparison to no involvement in ABCAFs particularly as it relates to ipsilateral joint replacement.

Finite element analysis of posterior acetabular column plate and posterior acetabular wall prostheses in treating posterior acetabular fractures.

BACKGROUND: The purpose of this study was to investigate the mechanical stability of the posterior acetabular column plate and different posterior acetabular wall prostheses used in treating posterior acetabular fractures with or without comminution. METHODS: The unilateral normal ilium was reconstructed, and a model of posterior acetabular wall fracture was established on this basis. The fracture fragment accounted for approximately 40% of the posterior acetabular wall. The posterior acetabular column plate and different posterior acetabular wall prostheses were also designed. Using static and dynamic analysis methods, we observed and compared the changes in the stress and displacement values of different models at different hip joint flexion angles under external forces. RESULTS: At different hip flexion angles, the stress of each model mainly fluctuated between 37.98 MPa and 1129.00 MPa, and the displacement mainly fluctuated between 0.076 and 6.955 mm. In the dynamic analysis, the nodal stress‒time curves of the models were nonlinear, and the stress changed sharply during the action time. Most of the nodal displacement‒time curves of the models were relatively smooth, with no dramatic changes in displacement during the action time; additionally, most of the curves were relatively consistent in shape. CONCLUSIONS: For simple posterior acetabular wall fractures, we recommend using a posterior acetabular column plate. In the case of comminuted posterior acetabular fractures, we recommend the use of a nonflanked posterior acetabular prosthesis or a biflanked posterior acetabular prosthesis. Regarding the method of acetabular prosthesis design, we propose the concept of "Break up to Make up" as a guide.

Time to revisit contraindications of vertebroplasty- A retrospective study of osteoporotic burst fracture operated with vertebroplasty and short segment fixation.

Background: To evaluate the safety and efficacy of vertebroplasty with short segmented cement augmented pedicle screws fixation for severe osteoporotic vertebral compression fractures (OVCF) with posterior/anterior wall fracture patients. Methods: A retrospective study of 48 patients of DGOU type-4 (vertebra plana) OVCF with posterior/anterior wall fracture, were treated by vertebroplasty and short segment PMMA cement augmented pedicle screws fixation. Radiological parameters (kyphosis angle and compression ratio) and clinical parameters Visual analogue scale (VAS) and Oswestry disability index (ODI) were analysed. Results: A significant improvement was noted in VAS (preoperative, 7.90±0.60; final follow-up 2.90±0.54) and ODI (77.10±6.96 to 21.30±6.70), (P<0.05). Neurological improvement was noted in all patients. Kyphosis corrected significantly from preoperative 23.20±5.90 to 5.30±1.40 postoperative with 5% (3.30±2.95) loss of correction at final follow-up. Anterior vertebral height restored significantly from 55.80±11.9% to 87.6±13.1% postoperative with 4.5±4.0% loss at final follow-up. Two cases of cement leakage were found, but both patients were asymptomatic. One patient had implant backout, one had Screw breakage and two had proximal junction kyphosis at final follow-up. No iatrogenic dural or nerve injury. Conclusions: Treatment with vertebroplasty with cement augmented screw fixation and direct decompression is a great option in treating such a complex situation in fragile age with fragile bones because. Vertebroplasty is a viable option for restoring vertebral anterior columns in patients who are considered as contraindications for vertebroplasty, like DGOU-4. It provides anterior support avoiding corpectomy, minimise blood loss, and also the duration of surgery. The addition of short segment fixation gives adequate support with less stress risers at the junctional area.

Posterior hip fracture-dislocation associated with posterior wall fracture of the acetabulum and ipsilateral comminuted trochanteric fracture of the femur: A case report.

INTRODUCTION AND IMPORTANCE: Traumatic posterior dislocation of the hip is often associated with fractures of the femoral head and posterior wall of the acetabulum. However, hip fracture-dislocation that includes the posterior wall of the acetabulum and the ipsilateral femoral trochanter is rare. There is no consensus on the bone that should be operated on first, the operative position, and the choice of implant for femoral fixation. CASE PRESENTATION: A 67-year-old man was brought to our emergency department after a 2-m fall. He was diagnosed with a hip fracture-dislocation associated with posterior wall acetabular fracture and ipsilateral femoral trochanteric fracture. Surgical reconstruction was performed with intramedullary nail (IMN) fixation of the femoral trochanteric lesion, followed by anatomically rigid acetabular fixation in the lateral decubitus position. At the 5-year follow-up after the injury, the patient showed good objective and subjective clinical outcomes. CLINICAL DISCUSSION: Fixing the femur first could allow an easier reduction and traction. The lateral decubitus position was useful, because fixation of the femur and the acetabulum could be performed without changing the position. When fixing the femoral trochanteric lesion, attention was paid to reduce the anteromedial cortex of the proximal fragment extramedullarly to the distal fragment to prevent complications such as cutout and implant breakage. CONCLUSION: Anatomically rigid fixation of the posterior wall of the acetabulum secondary to IMN fixation of the femur, with anteromedial cortical support in the lateral decubitus position, could achieve good objective and subjective clinical outcomes.

The Short- and Mid-term Follow-Up of Single-Column Fixation in Transverse and Posterior Wall Acetabular Fractures.

OBJECTIVE: To evaluate the radiological and clinical outcomes of the surgical treatment for transverse and posterior wall fractures using single-column posterior fixation. METHODS: From January 2009 to January 2018, a total of 24 patients with transverse and posterior wall acetabular fractures in our center were included in this retrospective study, including 17 males and seven females with a mean age of 47 years and a minimum follow-up of 1 year. All cases were closed fractures. All fractures were fixed with single-column fixation via the Kocher-Langenbeck approach. Primary outcome measures, including quality of reduction and clinical outcomes, were recorded by an independent observer, who also noted secondary outcome measures, including time to surgery, surgical time, intraoperative blood loss, and postoperative complications. RESULTS: Twenty-four patients (range, 26-74 years) included 17 males and seven females. There were 14 cases on the left side and 10 cases on the right side. The mean time from injury to surgery was 7.1 days. Mean intraoperative blood loss and surgical time were 405.4 mL and 135.8 min, respectively. The mean follow-up time was 29.5 months (range 12-96 months). All the acetabular fractures united within 5 months after surgery. The quality of reduction was graded as anatomical in 17 cases (70.8%), imperfect in three cases (12.5%), and poor in four cases (16.7%). According to grading system of Merle d' Aubigne and Postel, clinical outcomes at the final follow-up were excellent in 10 cases (41.7%), good in six cases (25.0%), fair in five cases (20.5%), and poor in three cases (12.5%). The excellent and good rate was 66.7%. There was a significant relation between the quality of reduction and clinical outcomes (P < 0.05). At follow-up, there were one case of sciatic nerve injury, one case of wound infection, two cases of deep vein thrombosis, two cases of avascular necrosis, three cases of heterotopic ossification, and five cases of postoperative traumatic arthritis. Three of these patients underwent reoperation, including one with heterotopic ossification affecting hip movement and two with femoral head necrosis. CONCLUSIONS: Our study shows that single-column posterior fixation of transverse and posterior wall acetabular fracture through the Kocher-Langenbeck approach can obtain satisfactory radiological and clinical outcomes if there is adequate indirect reduction of the anterior column.

A Novel Anatomical Locking Guide Plate for Treating Acetabular Transverse Posterior Wall Fracture: A Finite Element Analysis Study.

OBJECTIVE: To improve the treatment of the acetabular transverse posterior wall fracture (ATPWF), a novel anatomical locking guidance plate (NALGP) was designed and compared with traditional fixations using finite element analysis. METHODS: The ATPWF model was constructed using the three-dimensional finite element model of the half pelvis via the Mimics software and three internal devices were used to fix this model: the posterior-column locking plate with anterior-column screws (PCLP), double-column locking plates (DCLP), and NALGP. Next, mesh division was conducted by solid 187 tetrahedral elements in the workbench software. After defining the boundary condition and material properties, each assembly model was loaded in an increasing manner with a downward vertical force of 200, 400, and 600 N, respectively. The loading force was directed at 45 degrees upward in the coronal plane and 25 degrees backward in the sagittal plane. Finally, the stress distribution and stress peak of plates and screws were measured and evaluated, and the displacement of fracture fragments under different loading force was assessed among the three groups. RESULTS: For stress distribution, it was found that the stress mainly acted on the posterior-column plate, especially concentrated at the middle and lower section of the plate in all three groups after fixation on the ATPWF. In addition, most stresses of screws appeared on the lag screws instead of the common screws. The common screws in the NALGP group experienced larger stresses under all loading force, while those in the DCLP group withstood less stresses compared to those in the PCLP group. For the displacement of fracture fragments, the NALGP group were found to have less fracture fragment displacements than the PCLP group, but had comparable results to DCLP at both the transverse fracture and the posterior wall fracture sites. CONCLUSION: The newly-designed fixation device showed superiorities on fracture stabilization over PCLP, but had comparable stability to DCLP. This suggests that the DCLP might be unnecessary for treating ATPWF in some instances because it might cause bigger surgical trauma and blood loss.

A Case Report of Bilateral Asymmetrical Traumatic Hip Dislocation - A Rare Presentation.

INTRODUCTION: Asymmetric bilateral hip dislocations are very rarely reported in literature. We report a unique case of asymmetric traumatic bilateral hip dislocation in a 34-year-old male, describing the management and post-operative complications. CASE REPORT: A 34-year-old truck driver sustained injury to both his hips in a head on collision between two trucks while seated in the passenger seat. There was a delay in presentation at our institution as he was referred after 17 h of the trauma. After evaluation, he underwent closed reduction of both hips under intravenous anesthesia on the same day. The post-reduction assessment revealed a left-sided posterior wall fracture which was suspected due to the instability after reduction. Fixation of the fracture was done using two spring plates. The patient was followed up throughout his rehabilitation and thereafter when he resumed his occupation. Six months after the incident, the patient had pain-free, full range of motion of both hips. Three years after the surgery radiological investigations revealed changes suggestive of early avascular necrosis (AVN), however, the patient did not have any functional restriction. CONCLUSION: This is a case of bilateral asymmetric hip dislocation with left side posterior wall fracture. It is important to reduce the hip and also address the fracture as early as possible to prevent AVN.

Mapping of acetabular posterior wall fractures using a three-dimensional virtual reconstruction software.

INTRODUCTION: The aim of this study was to analyze and describe the fracture patterns of the acetabular posterior wall based on quantitative measurements of the fracture characteristics. MATERIALS AND METHODS: Computed tomography images of 51 patients with acetabular posterior wall fractures from an initial cohort of 216 acetabular fractures were imported into a three-dimensional (3D) virtual software. The reconstructed 3D images were utilized to evaluate the following: (i) fracture line mapping on the inner articular and retro-acetabular surfaces, (ii) common zones of fracture and marginal impaction, and (iii) categorization by location and pattern of comminution. The clock-face position was applied for description: the midpoint of the transverse acetabular ligament served as the +180° reference point, and the 0° reference point was set perpendicular to the ligament. The fracture angle on the articular surface was defined as the intersection between the start and end points. The fracture span on the retro-acetabular surface was defined as the ratio of the perpendicular distance, which is between the fracture beak and acetabular rim, to the entire length, which is from the edge to the rim. Quantitative measurements were performed, and the fracture patterns were analyzed. A color scale bar was used to visualize the common and marginal impaction zones. RESULTS: The articular surface mapping of all the cases demonstrated that the average starting point of the fracture line was +6.2° (±12.8°) and the endpoint was 96.7° (±13.3°), and the average fracture angle was 119.6° (±7.6°) with 80.6% of the fragments having angles within 18.7-117°. The retro-acetabular surface mapping demonstrated that the average fracture span was 0.65 ±0.20, and 61.7 % of the fracture lines were located within 0.6 to 0.9. Marginal impaction was found in 21 cases (21/51, 41.2%; range: between +7° and +105°). CONCLUSION: The fracture maps showed fracture patterns and recurrent fracture zones on the articular and retro-acetabular surfaces. However, there was no remarkable pattern of marginal impaction. LEVEL OF EVIDENCE: Retrospective cohort study.

[Application of new H-shaped anatomical titanium plate for posterior wall/posterior column acetabular fractures].

OBJECTIVE: To explore the effectiveness of a new H-shaped anatomical titanium plate in treatment of posterior wall/posterior column acetabular fractures. METHODS: Between March 2012 and April 2019, 46 patients with acetabular fractures involving posterior wall/posterior column were treated with the new H-shaped anatomical titanium plates. There were 28 males and 18 females. The age ranged from 20 to 70 years, with an average of 45.5 years. Among the patients, 34 cases were injured by traffic accidents and 12 cases by falling from height. The time from injury to operation ranged from 2 to 14 days, with an average of 7 days. According to Letournel-Judet classification, there were 12 cases of posterior wall fractures, 1 case of posterior column fracture, 3 cases of transverse fractures, 9 cases of transverse fractures involving posterior walls, 8 cases of posterior column and posterior wall fractures, 2 cases of anterior column and posterior semi-transverse fractures, 3 cases of T-shaped fractures, and 8 cases of double column fractures. Matta reduction standard was used to evaluate fracture reduction and Merle d'Aubign-Postel score was used to evaluate hip joint function. RESULTS: All operations were successfully completed. The time of posterior operation was 60-120 minutes, with an average of 80 minutes. The amount of intraoperative blood loss ranged from 200 to 600 mL, with an average of 300 mL. All the incisions healed by first intention and no infection, deep vein thrombosis, or sciatic nerve injury occurred. All 46 patients were followed up 6-72 months, with an average of 37 months. According to Matta reduction standard, 40 cases obtained anatomic reduction, 4 cases satisfactory reduction, 2 cases unsatisfactory reduction, and the satisfaction rate was 95.7% (44/46). All fractures healed, and the healing time was 3-6 months, with an average of 4.3 months. No internal fixation failure occurred during the follow-up. At last follow-up, the Merle d'Aubign-Postel score ranged from 6 to 18 (mean, 15.5), including 38 cases of excellent, 4 cases of good, 2 cases of fair, and 2 cases of poor, with an excellent and good rate of 91.3% (42/46). Heterotopic ossification occurred in 4 cases, traumatic arthritis in 4 cases, and osteonecrosis of femoral head in 2 cases after operation. CONCLUSION: For acetabular fractures involving posterior wall/posterior column, the new H-shaped anatomical titanium plate can provide stable fixation, satisfactory reduction, and good recovery of hip function.