Fractures of the posterior wall of the acetabulum: treatment using internal fixation of two parallel reconstruction plates

Novel implant design for comminuted posterior wall acetabular fractures

BACKGROUND

In recent years, the medical community has witnessed a notable increase in high-energy traumatic injuries, leading to a surge in complex fracture patterns that challenge existing treatment methodologies. Among these, the posterior approach to acetabular fractures stands out for offering direct visualization of the retro-acetabular surface, with current fixation methods relying on 3.5 mm low-profile reconstruction plates and various other implants. Despite the effectiveness of these methods, there is a burgeoning demand for a singular, adaptable implant that not only streamlines the surgical process but also optimizes patient outcomes.

METHODS

In an innovative approach to address this need, three-dimensional (3D) models of the posterior acetabular wall were meticulously crafted using AutoCAD® software. The chosen material for the implant was 316L surgical steel for its durability and strength. The design of the implant featured a low-profile mesh structure, which was instrumental in facilitating osteosynthesis. This design allowed for the placement of screws of varying lengths in multiple directions, ensuring the initial reconstruction of the joint in an anatomical position without hindering the placement of the definitive implant. The primary objective was to secure the fixation and stabilization of the fracture by specifically targeting the smaller bone fragments. A comparative analysis was then conducted between this novel plate and a conventional 316L surgical steel, seven-hole, 3.5 mm reconstruction plate through finite element analysis.

RESULTS

The comparative analysis unveiled that both plates demonstrated comparable deformation capacities, with no significant differences in load-bearing capabilities observed. This finding suggests that the innovative plate can match the performance of traditional plates used in such surgeries.

CONCLUSIONS

The finite element analysis revealed that the newly developed anatomical plate for posterior wall acetabular fractures meets the necessary physical and mechanical criteria for permanent implementation in patients with these fractures. This breakthrough represents a promising advancement that could simplify surgical procedures and potentially elevate patient outcomes.

LEVEL OF EVIDENCE II

This study is classified as a Level II, diagnostic study.

A novel anatomical self-locking plate fixation for both-column acetabular fractures

PURPOSE

To compare the stability of the posterior anatomic self-locking plate (PASP) with two types of popular reconstruction plate fixation, i.e. double reconstruction plate (DRP) and cross reconstruction plate (CRP), and to explore the influence of sitting and turning right/left on implants.

METHODS

PASP, DRP and CRP were assembled on a finite element model of both-column fractures of the left acetabulum. A load of 600 N and a torque of 8 N·m were loaded on the S1 vertebral body to detect the change of stress and displacement when sitting and turning right/left.

RESULTS

The peak stress and displacement of the three kinds of fixation methods under all loading conditions were CRP > DRP > PASP. The peak stress and displacement of PASP are 313.5 MPa and 1.15 mm respectively when turning right; and the minimal was 234.0 Mpa and 0.619 mm when turning left.

CONCLUSION

PASP can provide higher stability than DRP and CRP for both-column acetabular fractures. The rational movement after posterior DRP and PASP fixation for acetabular fracture is to turn to the ipsilateral side, which can avoid implant failure.

Posterior wall fractures of the acetabulum: treatment using an anatomical plate through direct posterior approach

OBJECTIVES

This study was aimed to measure the application of W-shaped acetabular angular plate (WAAP) through direct posterior approach (DPA) on the reconstruction of acetabular posterior wall fractures when compared with reconstruction plates.

PATIENTS AND METHODS

A retrospective study was performed on patients treated with the WAAP or reconstruction plates via the DPA. The intraoperative data of operative time, blood loss and radiation exposure times were recorded. Radiographs of the pelvis and CT scan were obtained within one week post-operation to assess the reduction quality. The clinical outcome was evaluated by the modified Merle d'Aubigne and Postel score.

RESULTS

From May 2016 to October 2019, a total of 41 patients with simple acetabular posterior wall fractures were included in this study, 22 from the WAAP group and 19 from the reconstruction plates group. There were no significant differences between the two group in age, gender, time from injury to operation, cause of injuries, length of incision and follow-up time (P > 0.05). In comparison with the reconstruction plates group, the average operation time of the WAAP group was significantly shorter (46.1 ± 12.7 min vs 59.2 ± 17.4 min, P < 0.05), the average radiation exposure times were significantly less (2.3 ± 0.6 vs 3.6 ± 1.0, P < 0.001), the average blood loss was significantly less (240 ± 98.9 ml vs 301.1 ± 66.6 ml, P < 0.05). According to Matta radiology criteria and the modified Merle d' Aubigne and Postel score, no significant difference was observed between the two group, as for the quality of reduction and function outcomes.

CONCLUSION

The application of WAAP through DPA showed satisfactory preliminary clinical outcomes, showing promise to be an alternative technique for the treatment of acetabular posterior wall fractures.

Acetabular Fractures with Central Hip Dislocation: A Retrospective Consecutive 50 Case Series Study Based on AO/OTA 2018 Classification in Midterm Follow-Up

Introduction

Management of acetabular fractures is challenging, especially when a medial acetabular fracture is complicated by central hip dislocation. We retrospectively investigated the clinical outcome and risk factors of secondary hip osteoarthritis requiring total hip arthroplasty after the surgical treatment of acetabular fractures with central hip dislocation.

Materials and Methods

The medical records of all patients who had acetabular medial wall fractures with central hip dislocation treated with open reduction and internal fixation by a single surgeon between January 2015 and June 2017 were reviewed. Surgical reduction was performed with the modified Stoppa with/without the Kocher-Langenbeck (KL) approach. Patients were followed for a minimum of three years, and the Majeed scoring system was used for functional evaluation. Multivariate logistic regression analysis was used to assess the association of patients' characteristics with the likelihood of advanced posttraumatic arthritis developing with conversion to total hip arthroplasty.

Results

Fifty patients were included in this study, with disease classified as AO/OTA 2018 62B/62C. Thirty-five patients (70%) had good or excellent Majeed pelvic scores. Eleven patients (22%) eventually received total hip arthroplasty because of end-stage posttraumatic arthritis. Three risk factors identified for total hip arthroplasty were male sex, initial marginal impaction, and sciatic nerve injury. Kaplan-Meier survivorship analysis estimated that the cumulative probability of free-from-end-stage arthritis was 78% (95% confidence interval, 73%–90%) at the 5-year follow-up.

Conclusion

Surgical fixation with the modified Stoppa and the KL approach for acetabular medial wall fractures with central hip dislocation is an effective approach with a satisfactory functional outcome. A prodromal factor was marginal impaction concomitant with articular damage. The trauma of high axial loading and the occupational distribution (males performing heavy manual labor and heavy lifting) with preoperative sciatic nerve injury increased the odds of developing end-stage arthritis.

[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.

Acetabulum Cup Stability in an Early Weight-Bearing Cadaveric Model of Geriatric Posterior Wall Fractures

BACKGROUND

Primary total hip arthroplasty (THA) has been suggested for posterior wall (PW) fractures with unfavorable features in the geriatric population. There is a paucity of studies reporting on postoperative protocols for primary THA after PW fractures. The purpose of this study was to test the biomechanical effect of immediate assisted weight-bearing on acetabulum THA cup fixation in an osteoporotic PW fracture model.

METHODS

Computed tomography scans of 18 geriatric PW fractures (mean age, 77 ± 8 years) were used to generate representative PW fracture. This fracture pattern, comprising 50% of the PW and 25% of the acetabulum rim, was then created in 6 female cadaveric pelves. A multihole acetabulum THA cup was implanted with line-to-line reaming and fixed with four 5-mm screws. The pelves were cyclically loaded to up to 1.8× body weight (BW) in the intact form, after fracture creation and fracture fixation. Optical markers were used to determine acceptable cup motion of less than 150 μm.

RESULTS

Five specimens withstood 3.6× BW loading after implantation and before fracture creation. At 1.8× BW load, cup motion was nonfractured: 50 ± 24 µm (range, 5-128 µm), fractured with no fixation: 37 ± 22 µm (range, 8-74 µm), or fractured with fixation: 62 ± 39 µm (range, 5-120 µm) (P = 0.0097). Cup motion was <150 µm for all groups.

CONCLUSION

This study supports the practice of allowing immediate assisted weight-bearing in patients undergoing THA with PW fractures involving up to 50% of the PW and up to 25% of the acetabular rim, with or without fixation of the PW fragment.

Surgical Treatment for Posterior Dislocation of Hip Combined with Acetabular Fractures Using Preoperative Virtual Simulation and Three-Dimensional Printing Model-Assisted Precontoured Plate Fixation Techniques

Background and Purpose

Hip dislocation combined with acetabular fracture remains a challenging condition for orthopedic surgeons. In this study, we utilized a computer-assisted simulation and three-dimensional (3D) printing technology to treat patients with hip dislocation combined with acetabular fracture. We hypothesized that the 3D printing-assisted method would shorten the internal fixation time and surgical time.

Methods

We retrospectively reviewed 16 patients diagnosed with traumatic posterior dislocation of hip combined with acetabular fractures and treated with plate fixation from September 2013 to August 2017. Patients were divided into two groups: (1) traditional method and (2) 3D printing groups. In the traditional method group, the plates were contoured during the surgery, whereas in the 3D printing group, the patient's pelvic computed tomography image was transformed to the 3D medical image software for processing preoperatively. The fracture reduction was simulated by the computer. Thereafter, the 1:1 scale 3D printing model was used to design the surgical plan and contour patient-specific plates preoperatively.

Results

The internal fixation time was significantly shorter in the 3D printing group than in the traditional method group (-33 min, P<0.05). The mean operative time was shorter than that in the traditional method group (-43 min). However, blood loss and postoperative radiograph results were similar between the groups. The complication rate was lower in the 3D printing group (2/7) than in the traditional method group (5/9).

Interpretation

Computer-assisted simulation with 3D printing technology is a more efficient method for treating hip dislocation combined with acetabular fractures.

Crescent Technique with Dual C-Shaped Reconstruction Plates for Posterior Acetabular Wall Fractures

Background: Here we have defined a novel technique for repairing posterior acetabular wall fractures called the "crescent technique," in which dual C-shaped reconstruction plates overlap at the distal ends and, if necessary, at the proximal ends. We also analyzed the efficacy and reliability of this method. Patients and Methods: This was a retrospective analysis of 27 patients undergoing the crescent technique. All of the fractures were treated by the senior author for a mean of 7.9 days (0-15 days) after the trauma. The mean follow-up period was 19 months (13-29 months). The clinical results were evaluated using the modified clinical grading system developed by Merle d'Aubigne and Postel, and then modified by Matta. The radiographs were graded according to the criteria described by Matta. Results: In the clinical grading, 16 (59%) of the patients were excellent and very good, 5 (19%) were good, 3 (11%) were moderate, and 3 (11%) were poor. According to the Matta radiological evaluation criteria, 19 (70%) were excellent, 4 (15%) were good, 4 (15%) were fair, and none were poor. Statistically significant consistency was seen between the clinical and radiological results (p = 0.002). Conclusions: The crescent technique is a dual plate technique modification that can provide a stable fixation. It appears to be an effective and reliable method for treating posterior wall fractures of the acetabulum.

Reconstruction of acetabular posterior wall fractures with extension to the roof using dual arc-shaped plates: A case report

Anatomical reduction and rigid fixation of acetabular posterior wall fractures extending to the acetabular roof proves challenging because of the big bony fragment and muscular obstruction to accessing this region. This report describes a novel reconstructive technique in a patient with an acetabular posterior wall fracture involving the acetabular roof. Both the standard Kocher-Langenbeck approach and a greater trochanter osteotomy technique were used. Following anatomical reduction, a dual arc-shaped reconstruction plate technique was employed to achieve rigid fixation. The patient recovered with satisfactory function at the injured hip. We recommend this dual arc-shaped reconstruction plate technique for the treatment of acetabular posterior wall fractures extending to the acetabular roof in clinical practice.

Learning Curve for Surgical Treatment of Acetabular Fractures: A Retrospective Clinical Study of a Practical and Theoretical Training Course

Background

Surgical treatment of acetabular fracture and the anatomic reconstruction of the hip joint are difficult to achieve due to the complex pelvic anatomy, and surgical training requires a prolonged and steep learning curve. The aim of this study was to evaluate the effects of an applied training course, including cadaveric dissection, for the surgical treatment of acetabular fractures.

Material/Methods

This retrospective study included 35 patients who underwent surgical treatment for acetabulum fractures between 2012–2016. Patients were divided into three groups during two training courses, for the first two years and second two years. The surgical treatment was performed through single or combined standard approaches, according to the fracture pattern. The radiological outcome was evaluated using Matta’s criteria to grade postoperative reduction and final radiological outcome and the restoration of the hip joint center (HJC). The clinical outcome was evaluated using the modified the Merle d’Aubigné-Postel (DAP) hip score.

Results

Both post-course groups had statistically better functional and radiological outcomes compared with the pre-course group. Depending on the learning curve, the mean duration of surgery decreased from 153 minutes to 82.3 minutes. Although there was no statistical difference between groups in the vertical shift of the HJC, there was a statistically significant in the amount of horizontal shift of the HJC in the second two years of training, compared with the other groups.

Conclusions

Functional and radiological outcome of surgical treatment of acetabular fracture may be improved with increased training, depending on the learning curve.

Early Versus Late Weight-Bearing Protocols for Surgically Managed Posterior Wall Acetabular Fractures

Despite overall improved outcomes with open reduction and internal fixation of acetabular fractures, posterior wall fractures show disproportionately poor results. The effect of weight bearing on outcomes of fracture management has been investigated in many lower extremity fractures, but evidence-based recommendations in posterior wall acetabular fractures are lacking. The authors systematically reviewed the current literature to determine if a difference in outcome exists between early and late postoperative weight-bearing protocols for surgically managed posterior wall acetabular fractures. PubMed and MEDLINE were searched for posterior wall acetabular fracture studies that included weight-bearing protocols and Merle d'Aubigné functional scores. Twelve studies were identified. Each study was classified as either early or late weight bearing. Early weight bearing was defined as full, unrestricted weight bearing at or before 12 weeks postoperatively. Late weight bearing was defined as restricted weight bearing for greater than 12 weeks postoperatively. The 2 categories were then compared by functional score using a 2-tailed t test and by complication rate using chi-square analysis. Six studies (152 fractures) were placed in the early weight-bearing category. Six studies (302 fractures) were placed in the late weight-bearing category. No significant difference in Merle d'Aubigné functional scores was found between the 2 groups. No difference was found regarding heterotopic ossification, avascular necrosis, superficial infections, total infections, or osteoarthritis. This systematic review found no difference in functional outcome scores or complication rates between early and late weight-bearing protocols for surgically treated posterior wall fractures. [Orthopedics. 2017: 40(4):e652-e657.].

Radiographic Measurement of Displacement in Acetabular Fractures: A Systematic Review of the Literature

OBJECTIVES

To report methods of measurement of radiographic displacement and radiographic outcomes in acetabular fractures described in the literature.

METHODS

A systematic review of the English literature was performed using EMBASE and Medline in August 2014. Inclusion criteria were studies of operatively treated acetabular fractures in adults with acute (<6 weeks) open reduction and internal fixation that reported radiographic outcomes. Exclusion criteria included case series with <10 patients, fractures managed >6 weeks from injury, acute total hip arthroplasty, periprosthetic fractures, time frame of radiographic outcomes not stated, missing radiographic outcome data, and non-English language articles. Basic information collected included journal, author, year published, number of fractures, and fracture types. Specific data collected included radiographic outcome data, method of measuring radiographic displacement, and methods of interpreting or categorizing radiographic outcomes.

DATA SYNTHESIS

The number of reproducible radiographic measurement techniques (2/64) and previously described radiographic interpretation methods (4) were recorded. One radiographic reduction grading criterion (Matta) was used nearly universally in articles that used previously described criteria. Overall, 70% of articles using this criteria documented anatomic reductions.

CONCLUSIONS

The current standard of measuring radiographic displacement in publications dealing with acetabulum fractures almost universally lacks basic description, making further scientific rigor, such as testing reproducibility, impossible. Further work is necessary to standardize radiographic measurement techniques, test their reproducibility, and qualify their validity or determine which measurements are important to clinical outcomes.

LEVEL OF EVIDENCE

Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Assessment of functional outcomes of surgically managed acetabular fractures

We performed a systematic review of the literature pertaining to the functional outcomes of the surgical management of acetabular fractures. A total of 69 articles met our inclusion criteria, revealing that eight generic outcome instruments were used, along with five specific instruments. The majority of studies reported outcomes using a version of the d’Aubigne and Postel score, which has not been validated for use in acetabular fracture. Few validated outcome measures were reported. No psychometric testing of outcome instruments was performed. The current assessment of outcomes in surgery for acetabular fractures lacks scientific rigour, and does not give reliable outcome data for either scientific comparison or patient counselling.

Take home message: The use of non-validated functional outcome measures is a major limitation of the current literature pertaining to surgical management of acetabular fractures; future studies should use validated outcome measures to ensure the legitimacy of the reported results.

Cite this article: Bone Joint J 2016;98-B:690–5.