Anteriore Zugänge zum Acetabulum

Anterior extrapelvic approaches to the acetabulum

Anterior approaches to the acetabulum can be distinguished into extrapelvic, intrapelvic and combined extrapelvic and intrapelvic approaches. Historically, the extrapelvic ilioinguinal approach was introduced in the French, English and German literature during the late 60s and became gradually the Gold-standard in treating anterior acetabular fractures. In the meantime, the intrapelvic approach, introduced by the Helsinki group, is favored by many surgeons with ongoing interest allowing direct antero-medial access to the true pelvis below the linea terminalis, to the quadrilateral plate and medial side of the posterior column. More recently, more supero-medial approaches, allowing access to the large and true pelvis have been developed, e.g. the Pararectus approach. The historical development, the value and approach-related results of the ilioinguinal approach are analyzed and discussed.

Posterior approaches to the acetabulum

Posterior approaches, particularly the Kocher-Langenbeck approach, remain the workhorses in the treatment of acetabular fractures. Various modifications have been developed, each offering specific advantages depending on surgical requirements. The modified Gibson approach, for example, is suggested to provide enhanced visualization of the superior acetabulum, although recent cadaveric studies have not consistently substantiated this benefit. The Ganz approach, which involves bigastric trochanteric osteotomy with safe surgical hip dislocation, is particularly advantageous for managing complex and comminuted posterior acetabular fractures, as it enables a 360° view of the acetabulum and femoral head. Overall, posterior approaches are associated with low rates of complications, with heterotopic ossification being the most prevalent. The choice of surgical approach and patient positioning should be guided by the surgeon's preference and expertise, tailored to the specific fracture pattern and patient characteristics.

The Pararectus approach: a preferred surgical approach for fixation of acetabular fractures predominantly involving the anterior column - a narrative review

Beginning in France in the 1960s, the management of acetabular fractures has increasingly evolved toward surgical treatment strategies. The basic principles established by the pioneers of acetabular surgery, Letournel and Judet - anatomical reconstruction of the joint and stable osteosynthesis - remain unchanged. Modern advancements in surgical techniques aim to reduce access-related trauma and minimize complications. The notable rise in acetabular fractures among the elderly, which predominantly affect the anterior aspects of the acetabulum, has driven the development of less invasive, soft tissue-sparing anterior approaches. This evolution began with the ilio-inguinal approach in the 1960s, progressed to the modified Stoppa approach in the 2000s and, most recently, the Pararectus approach in the 2010s. Each of these approaches upholds the fundamental principles of effective acetabular fracture care, while offering distinct advantages and disadvantages. In this review, we examine the merits and limitations of the Pararectus approach, specifically focusing on its utility in the surgical treatment of anterior column posterior hemitransverse acetabular fractures. Ultimately, the success of the individual patient's outcome is less dependent on the chosen approach and more on the surgeon's experience and expertise. Ideally, surgeons should be proficient in all these approaches to tailor the surgical strategy to the individual patient's requirements, thereby ensuring optimal outcomes.

[The pararectus approach: surgical procedure for acetabular fractures]

OBJECTIVE

The pararectus approach was rediscovered several years ago for pelvic surgery and described as an alternative approach especially for the treatment of acetabular fractures of the anterior column involving the quadrilateral plate.

INDICATIONS

For optimal visualization of acetabular fractures involving the quadrilateral plate, fractures of the anterior wall and anterior column, anterior column/posterior hemitransverse fractures, and fractures with central impression of dome fragments, the pararectus approach has proven to be a useful access.

CONTRAINDICATIONS

The pararectus approach is not used for posterior column fractures, posterior wall fractures, combined posterior wall and posterior column fractures, transverse fractures with displaced posterior column or in combination with posterior wall fractures, and T‑fractures with displaced posterior column or in combination with posterior wall fractures.

SURGICAL TECHNIQUE

The entire pelvic ring, including the quadrilateral plate, can be accessed via the pararectus approach. The choice of the correct surgical window depends on the fracture location and the requirements of fracture reduction.

POSTOPERATIVE MANAGEMENT

In general, partial weight-bearing should be maintained for 6 weeks, although earlier weight-bearing release may be possible if necessary, depending on fracture pattern and osteosynthesis. Particularly in geriatric patients, partial weight-bearing is often not possible, so that early and often relatively uncontrolled full weight-bearing has to be accepted.

RESULTS

In a comparative gait analysis between patients following surgical stabilization of an isolated unilateral acetabular fracture through the pararectus approach and healthy subjects, sufficient stability and motion function of the pelvis and hip during walking was already evident in the early postoperative phase.

[Techniques and results of primary hip arthroplasty in geriatric acetabular fractures]

As a result of demographic changes, there is an increase in geriatric acetabular fractures [1, 2]. Geriatric patients often have comorbidities, such as pre-existing coxarthritis, reduced bone quality or limited compliance, which makes injury-adapted follow-up treatment difficult [3]. As a result joint-preserving interventions often fail at an early stage, so that hip arthroplasty is necessary in the short term. The 1‑year mortality after surgically stabilized acetabular fractures is 8.1%, a significant increase by a factor of 4 compared to the age group [4]. This illustrates that differentiated criteria for the indication of joint-preserving surgery versus arthroplasty are necessary to avoid reoperations and complications. Criteria for the indications for primary arthroplasty are fracture type, pre-existing coxarthritis, poor bone quality, limited compliance and patient age (> 75 years) [5, 6].In the following article, three treatment strategies for geriatric acetabular fractures and periprosthetic acetabular fractures are presented; the 1‑stage prosthesis implantation without osteosynthesis, the 1‑stage prosthesis implantation with osteosynthesis and the 2‑stage approach with limited osteosynthesis and early total arthroplasty. The advantages and disadvantages of these options are presented based on cases and the various aspects of the treatment. The treatment of geriatric acetabular fractures is an operative challenge for the surgeon and requires a high level of expertise in both special trauma surgery and revision arthroplasty and thus represents a special interface in the fields of orthopedics and trauma surgery.

Oblique-ilioischial plate technique: a novel method for acetabular fractures involving low posterior column

Background

Complex acetabular fractures involving the anterior and posterior columns are an intractable clinical challenge. The study investigated the safety and efficacy of oblique-ilioischial plate technique for acetabular fractures involving low posterior column.

Methods

A retrospective analysis of 18 patients operated with the oblique-ilioischial plate technique by the modified Stoppa approach (or combined with iliac fossa approach) between August 2016 and July 2021 for low posterior column acetabular fractures was conducted. The anterior column was fixed with a reconstructed plate from the iliac wing along the iliopectineal line to the pubis. The low posterior column was fixed with the novel oblique-ilioischial plate running from the ilium to the ischial ramus. Operative time, intraoperative blood loss, reduction quality, and postoperative hip function were recorded.

Results

Out of the 18 patients, 10 were male and 8 were female. The mean age was 48.6±10.2 years (range: 45–62 years); The mean interval from injury to operation was 7.2±1.4 days (range: 5–19 days); The mean operative time was 2.1±0.3 h (range: 1.0–3.2 hours); The mean intraoperative blood loss was 300±58.4 mL (range: 200–500 mL). Postoperative reduction (Matta’s criteria) was deemed as excellent (n = 9), good (n = 4), and fair (n = 5). At the final follow-up, the hip function (modified Merle d’Aubigne-Postel scale) was deemed as excellent (n = 11), good (n = 3), and fair (n = 4). The mean union time was 4.5±1.8 months (range: 3–6 months). No implant failure, infection, heterotopic ossification, or neurovascular injury were reported.

Conclusion

The oblique-ilioischial plate technique via anterior approach for acetabular fractures involving low posterior column offers reliable fixation, limited invasion, little intraoperative bleeding, and fewer complications. However, larger multicenter control studies are warranted.

A new modified pararectus approach and visualization: an anatomical study

INTRODUCTION

The aim of our study was to visualize all the windows used in the pararectus approach with detailed cadaver images to facilitate better understanding of orthopedic surgeons and, in addition, was to modify the incision used in the pararectus approach to a more cosmetic bikini incision.

MATERIALS AND METHODS

In total, 20 cadavers fixed in 10% formalin were used in this study. Of these cadavers, 14 were male and six were female, with a mean age at death of 57 (42-82 years). The four windows were defined as follows in all the cadavers: pubic, quadrilateral, sacroiliac, and iliac windows.

RESULTS

The most important structure at risk in the pubic window was the corona mortis, as it was observed in 12 (60%) cadavers. In men, the spermatic cord was an important structure at risk in the pubic window. The obturator vessels and nerves were the structures at most risk in the quadrilateral window due to their close location with the quadrilateral surface. The obturator nerve on the medial side and at the entrance of the pelvis through the linea terminalis and lumbosacral truncus were the structures at most risk close to the sacroiliac joint in the sacroiliac window.

CONCLUSION

This anatomical study includes highly instructive visual shapes and cadaver images for the acetabulum and pelvis, whose anatomical structures are quite complex. We have found that this modified pararectus approach provides excellent access to the internal pelvic rim.

CLINICAL RELEVANCE

The anatomical data regarding the modified pararectus approach in this study will assist orthopedic surgeons in the surgical management of acetabular and pelvic fractures.

Pararectus approach vs. Stoppa approach for the treatment of acetabular fractures - a comparison of approach-related complications and operative outcome parameters from the German Pelvic Registry

PURPOSE

The Pararectus approach has been introduced as an alternative anterior approach to the Stoppa approach in acetabular surgery. There is no evidence which approach should be preferred, especially regarding approach-related complications. Therefore, aim of this registry study was to compare the Pararectus approach to the Stoppa approach regarding complications and quality of reduction.

METHODS

Patients from the German Pelvic Registry with a surgically treated acetabular fracture, either through the Pararectus approach or the Stoppa approach, were analyzed or compared regarding demographic, clinical and operative parameters.

RESULTS

In total, 384 patients with an acetabular fracture received a surgical procedure with either the Pararectus approach (n=120) or the Stoppa approach (n=264). There were no differences between the two groups regarding demographic parameters and fracture pattern. The overall complication rate (35.0% vs. 31.4%), the mortality rate (5.0% vs. 3.0%) and the osteosynthesis-associated complication rate (5.8% vs. 4.2%) tended to be higher in the Pararectus group with no statistical significance. There were significantly more anatomical reductions in the Pararectus group (56% vs. 43%; p=0.01). However, operation time was significantly longer in the Pararectus group (255±125 vs. 205±103 minutes; p<0.001).

CONCLUSION

Despite a longer operation time, the Pararectus approach and the Stoppa approach are equivalently applicable for the treatment of acetabular fractures regarding complication rates and quality of reduction.

LEVEL OF EVIDENCE

III, retrospective comparative study.

Laparoscopic Acetabular Surgery (LASY) - vision or illusion?

Displaced acetabular fractures usually require open surgical approaches. Aim of this cadaver study was to evaluate a laparoscopic approach to prepare the anterior acetabular column and the quadrilateral plate in analogy to the laparoscopic pelvic lymphadenectomy. The laparoscopic preparation and anatomy is presented and illustrated step by step in a human cadaver followed by a modular plate osteosynthesis of the anterior column involving the quadrilateral plate is performed via a minimally invasive approach using standard laparoscopic instruments. In conclusion we could demonstrate that the laparoscopic preperitoneal preparation of the acetabulum according to the laparoscopic pelvic lymphadenectomy provides more free range for the surgical instruments compared to a previously described total extraperitoneal approach. The development of specific reduction tools and implants is under investigation. Until then, at least the laparoscopic preparation could be introduced in the clinical setting in the near future. TYPE OF STUDY: Technical note - Cadaver study.

[Periprosthetic fractures of the acetabulum: osteosynthesis]

In most cases periprosthetic fractures of the acetabulum are complex injuries and are extremely challenging for the treating medical team. Over the years the frequency of this overall rare entity has increased due to demographic changes. In recent years several treatment algorithms were published and provided the possibility of developing standardized treatment concepts. The classification of the fractures and a dedicated preoperative strategy are highly important for the quality of patient-centered care. In the literature the frequency of intraoperative fractures was initially given as 0.4%; however, several studies have been published in which a far higher rate of intraoperative fractures was detected by computed tomography (CT), often referred to as so-called occult fractures. The causes are multifactorial and there is significant association with whether cement-free press-fit acetabular cups were used or cemented forms. In approximately 75% of the cases a low energy impact was the cause of the fracture. In these patients systemic processes, such as osteoporotic alterations of the bony substance or the possible presence of low-grade infections should be considered. This article gives an overview of the diagnostics, planning, challenges and osteosynthetic treatment options for periprosthetic fractures of the acetabulum.

Short-term results of surgical treatment of acetabular fractures using the modified Stoppa approach

BACKGROUND

As the more commonly used ilioinguinal approach is extensive and associated with complications arising from the dissection along the inguinal canal, we attempt to evaluate the efficacy of the modified Stoppa approach as an alternative in the operative management of acetabular fractures.

METHODS

Twenty-three patients with acetabular fractures, were operated by the modified Stoppa approach. Fractures were classified; operative time and blood loss were recorded; the radiological and clinical outcomes were prospectively analysed. We analysed the radiological results according to the criteria of Matta and the clinical results by the Merle d'Aubigne and Postel score with a mean follow up of 15.13 months.

RESULTS

The clinical outcomes were excellent or good in nineteen cases, fair and poor in two patients each. In eighteen of our cases the reduction was anatomic, imperfect in two cases, and poor in three cases. The mean pre-operative displacements on axial, sagittal and coronal NCCT sections were 3.8, 3.1 and 3.6 mm, respectively; and mean post-operative displacements were 0.2, 0.3 and 0.2 mm, respectively. The mean pre-operative and post-operative fracture gap were 12.8 mm and 1.1 mm respectively.

CONCLUSIONS

Minimizing perioperative morbidity and simultaneously allowing access for anatomical reduction are the major benefits of the approach. The modified Stoppa approach can substitute the ilioinguinal approach for the surgical fixation of acetabular fractures.

MODIFIED STOPPA APPROACH FOR PELVIC AND ACETABULAR FRACTURE TREATMENT

OBJECTIVE

A retrospective review aims to investigate the operative methods and therapeutic effects of the modified Stoppa approach for treating pelvic and acetabular fractures.

METHODS

18 patients with acetabular fracture of the anterior column and pelvic anterior ring fracture underwent surgical treatment using the modified Stoppa approach. Some of the treatment was combined with the iliac fossa approach or rear K-L approach. Fracture reduction and postoperative function were evaluated using the Matta scoring standard and the Majeed scoring system. The Oxford Centre for Evidence-Based Medicine system was used to grade the literature review and create graded B recommendations.

RESULTS

Incision length was 6-12 cm (mean, 10 cm), operative duration was 50-150 minutes (mean, 85 minutes), and intraoperative blood loss volume was 400-1,000 ml (mean, 500 ml). 18 patients were followed up for 12-36 months post-operation. In the results of X-ray films, 12 cases were anatomical reductions and the remaining cases were satisfactory reductions. According to Majeed standard, 13 patients were excellent and five patients were good.

CONCLUSIONS

Treatment using the modified Stoppa approach was suitable for anterior approaches, in which pelvic and acetabular fractures were sufficiently exposed, the fracture was conveniently reduced, less complications occurred, and curative effect was satisfactory. Level of evidence III, Retrospective comparative study.

EASY (endoscopic approach to the symphysis): a new minimally invasive approach for the plate osteosynthesis of the symphysis and the anterior pelvic ring-a cadaver study and first clinical results

BACKGROUND

Minimally invasive surgical approaches to reduce approach-associated morbidity are an interdisciplinary goal in surgery. In principle, the endoscopic approach for the extraperitoneal repair of groin hernias is the minimally invasive variant of the modified Stoppa-approach, which is used for the treatment of pelvic ring injuries in traumatology.

METHOD

Anatomical feasibility study regarding the plate osteosynthesis of the anterior pelvic ring via a minimally invasive variant of the modified Stoppa-approach.

RESULTS

We present the minimally invasive variant of the modified Stoppa-approach in a human cadaver step by step, both photographically and radiologically. Feasibility of the plate osteosynthesis of the symphysis is presented in a patient with open book injury via the minimally invasive approach using standard laparoscopic instruments.

CONCLUSION

The plate osteosynthesis of the anterior pelvic ring via the minimally invasive variant of the modified Stoppa-approach is feasible with existing standard laparoscopic instruments.

Surgical Treatment of Displaced Acetabular Fractures Using a Modified Stoppa Approach

A retrospective evaluation was performed of 36 patients (25 males and 11 females; average age, 44 years) with displaced acetabular fractures who were treated with a modified Stoppa approach. Fractures included 18 anterior columns, 2 both columns, 8 anterior columns with posterior hemitransverse, 6 transverse, and 2 T-type, according to the Judet and Letournel classification. Range of motion, Harris Hip Scores, and Merle d'Aubigné scores were evaluated. Pre- and postoperative measurements taken included displacements and gaps on axial, coronal, and sagittal computed tomography (CT) images and postreduction quality assessed radiologically. Mean follow-up was 14.7 months. Mean perioperative bleeding was 970 cc (range, 800-1250 cc). Mean Harris Hip Score was 77.9, mean Merle d'Aubigné score was 16.4, mean flexion was 105.2°, and mean extension was 16.9°. Anatomical reduction of the acetabular fracture was achieved in 29 (80.5%) patients; it was satisfactory in 5 (13.8%) and poor in 2 (5%). Mean preoperative displacements on axial, coronal, and sagittal sections were 4.1, 3.6, and 3.1 mm, respectively, and mean postoperative displacements were 0.2, 0.3, and 0.2 mm, respectively. Mean preoperative gap distance was 14.5 mm, and mean postoperative gap distance was 1.1 mm. Postoperative foot drop was observed in 2 patients, obturator nerve damage in 1, partial iliac vein damage in 1, and avascular necrosis of the femoral head in 1. Despite a steep learning curve, the modified Stoppa approach is a good alternative to the ilioinguinal approach. It can be used to treat many complex acetabular fractures.

Surgical exposures and options for instrumentation in acetabular fracture fixation: Pararectus approach versus the modified Stoppa

BACKGROUND

As an alternative to the modified Stoppa approach, the Pararectus approach is used clinically for treatment of acetabular fractures involving the anterior column. The current study assessed the surgical exposure and the options for instrumentation using both of these approaches.

METHODS

Surgical dissections were conducted on five human cadavers (all male, mean age 88 years (82-97)) using the modified Stoppa and the Pararectus approach, with the same skin incision length (10cm). Distal boundaries of the exposed bony surfaces were marked using a chisel. After removal of all soft-tissues, distances from the boundaries in the false and true pelvis were measured with reference to the pelvic brim. The exposed bone was coloured and calibrated digital images of each inner hemipelvis were taken. The amount of exposed surface using both approaches was assessed and represented as a percentage of the total bony surface of each hemipelvis. For instrumentation, a suprapectineal quadrilateral buttress plate was used. Screw lengths were documented, and three-dimensional CT reconstructions were performed to assess screw trajectories qualitatively. Wilcoxon's signed rank test for paired groups was used (level of significance: p<0.05).

RESULTS

After utilization of the Pararectus approach, the distances from the farthest boundaries of exposed bone towards the pelvic brim were significantly higher in the false but not the true pelvis, compared to the modified Stoppa approach. The percentage (mean±SD) of exposed bone accessible after utilizing the Pararectus approach was 42±8%, compared to 29±6% using the modified Stoppa (p=0.011). In cadavers exposed by the Pararectus approach, screws placed for posterior fixation and as a posterior column screw were longer by factor 1.8 and 2.1, respectively (p<0.05), and screws could be placed more posteromedial towards the posterior inferior iliac spine or in line with the posterior column directed towards the ischial tuberosity.

CONCLUSION

Compared to the modified Stoppa, the Pararectus approach facilitates a greater surgical access in the false pelvis, provides versatility for fracture fixation in the posterior pelvic ring and allows for the option to extend the approach without a new incision.

What is the frequency of nerve injuries associated with acetabular fractures?

BACKGROUND

Acetabular fractures and surgical interventions used to treat them can result in nerve injuries. To date, only small case studies have tried to explore the frequency of nerve injuries and their association with patient and treatment characteristics. High-quality data on the risk of traumatic and iatrogenic nerve lesions and their epidemiology in relation to different fracture types and surgical approaches are lacking.

QUESTIONS/PURPOSES

The purpose of this study was to determine (1) the proportion of patients who develop nerve injuries after acetabular fracture; (2) which fracture type(s) are associated with increased nerve injury risk; and (3) which surgical approach was associated with the highest proportion of patients developing nerve injuries using data from the German Pelvic Trauma Registry. Two secondary aims were (4) to assess hospital volume-nerve-injury relationship; and (5) internal data validity.

METHODS

Between March 2001 and June 2012, 2236 patients with acetabular fractures were entered into a prospectively maintained registry from 29 hospitals; of those, 2073 (92.7%) had complete records on the endpoints of interest in this retrospective study and were analyzed. The neurological status in these patients was captured at their admission and at the discharge. A total of 1395 of 2073 (67%) patients underwent surgery, and the proportions of intervention-related and other hospital-acquired nerve injuries were obtained. Overall proportions of patients developing nerve injuries, risk based on fracture type, and risk of surgical approach type were analyzed.

RESULTS

The proportion of patients being diagnosed with nerve injuries at hospital admission was 4% (76 of 2073) and at discharge 7% (134 or 2073). Patients with fractures of the "posterior wall" (relative risk [RR], 2.0; 95% confidence interval [CI], 1.4-2.8; p=0.001), "posterior column and posterior wall" (RR, 2.9; CI, 1.6-5.0; p=0.002), and "transverse+posterior wall" fracture (RR, 2.1; CI, 1.3-3.5; p=0.010) were more likely to have nerve injuries at hospital discharge. The proportion of patients with intervention-related nerve injuries and that of patients with other hospital-acquired nerve injuries was 2% (24 of 1395 and 46 of 2073, respectively). They both were associated with the Kocher-Langenbeck approach (RR, 3.0; CI, 1.4-6.2; p=0.006; and RR, 2.4; CI, 1.4-4.3; p=0.004, respectively).

CONCLUSIONS

Acetabular fractures with the involvement of posterior wall were most commonly accompanied with nerve injuries. The data suggest also that Kocher-Langenbeck approach to the pelvic ring is associated with a higher risk of perioperative nerve injuries. Trauma surgeons should be aware of common nerve injuries, particularly in posterior wall fractures. The results of the study should help provide patients with more exact information on the risk of perioperative nerve injuries in acetabular fractures.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

The Stoppa approach versus the ilioinguinal approach for anterior acetabular fractures: a case control study assessing blood loss complications and function outcomes

BACKGROUND

The modified Stoppa approach was introduced to manage fracture of the anterior column instead of the ilioinguinal approach to reduce morbidity. However there is no clinical evidence to confirm its efficiency. Therefore this study was designed to ascertain: (1) if the Stoppa approach versus ilioinguinal allows less blood loss, (2) if functional and radiological results are superior to that of the ilioinguinal approach, (3) if the rate of complication was different.

HYPOTHESIS

The modified Stoppa approach allows less blood loss than the ilioinguinal in management of fractures of the anterior column of the acetabulum.

PATIENTS AND METHODS

Nineteen patients who were treated with the ilioinguinal approach (Group A) at a mean follow-up of 33 months and 17 patients who were treated with the modified Stoppa approach (Group B) at a mean follow-up of 28.9 months were retrospectively reviewed. Patients were called to the final follow-up examination, mean follow-up durations were set and the functional evaluation of patients was made with measurement of range of motion, Harris Hip Scores (HHS), and Merle D'Aubigné score.

RESULTS

Average blood loss was determined at a mean 1170 mL (range, 750-2150 mL) in Group A and at a mean 1110 mL (range, 450-2000 mL) in Group B (P=0.168). The mean HHS (group A=89.4 [73-99] and group B=88.4 [75-97]) and Merle D'Aubigné scores (group A=16.8 [13-18] and group B=16.5 [13-18]) showed no significant difference between the groups (P=0.169). At the final follow-up, the mean hip flexion was found to be 106.83 ± 12.47 and the hip extension was 10.33 ± 6.12 in Group A, while these values were 103.71 ± 14.32 and 10.69 ± 8.17 in Group B (NS between groups regarding flexion [P=0.678] and extension [P=0.445]). The complication rate was 31% in Group A (6 patients) and 23% in Group B (4 patients) (P>0.05).

DISCUSSION

Both surgical approaches give successful results in the treatment of acetabular fractures. Contrary to expectations, there was no difference in the amount of bleeding at the wound site from the Stoppa technique, even though it is minimally invasive, compared to the ilioinguinal approach.

LEVEL OF EVIDENCE

Level III retrospective case control study.