The Stoppa approach for acetabular fracture

Objective

Acetabular fractures pose a great surgical challenge for orthopedic trauma surgeons. We believe that the Stoppa approach with an iliac window extension, previously described as a modified Stoppa approach is adequate for the majority of acetabular fractures excluding those with predominant posterior wall involvement. In this paper we will present our experience in using the Stoppa approach, its indications, preparations, the detailed surgical approach, complications and the different tips used in this relatively modern approach.

Indications

All simple and combined fracture types that involve the anterior column of the pelvis including the quadrilateral plate.

Contraindications

Posterior wall or extensive posterior column involvement. Transverse and T-fractures with mainly posterior displacement.

Surgical technique

Suprapubic, intrapelvic approach, extending from the symphysis pubis anteriorly to the sacroiliac joint posteriorly. Superficial landmarks are identical to the Pfannenstiel approach, the rectus abdominis muscles are longitudinally dissected, the symphysis pubis is exposed and a sub-periosteal deep surgical dissection is carried out along the anterior column and the quadrilateral plate, and posteriorly toward the greater sciatic notch and the sacroiliac joint.

Results

In a 5-year review of 60 acetabular fractures that underwent open reduction and internal fixation using the modified Stoppa approach, there were 36% anterior column fractures, 28% both-column fractures, the rest being anterior column with posterior hemi transverse fractures, transverse and T-fractures. Any extension of the fracture to the iliac wing necessitated an additional lateral window (93% of cases). In cases with posterior displacement, an additional approach was utilized to address a posterior wall fracture. All fractures healed within 12?weeks. Mean Merle d’Aubigné score was 15.22. Postoperative radiological evaluation revealed anatomical reduction in 54% of the patients, satisfactory in 43%, and unsatisfactory in 3% of the patients. Overall there were 15?minor and major complications     

Digastric trochanteric flip osteotomy and surgical dislocation of hip in the management of acetabular fractures

Objectives

To assess the efficacy and safety of digastric trochanteric flip osteotomy technique in the management of acetabular fractures and to evaluate surgical outcome in terms of fracture reduction, femoral head viability of selected acetabular fractures treated operatively using a digastric trochanteric flip osteotomy and a modified Kocher–Langenbeck approach with surgical dislocation of the femoral head.

Design

Prospective.

Patients

Eighteen patients predominantly with combined transverse and posterior wall fractures or multifragmentary posterior wall fractures.

Outcome evaluation

Clinical and radiographic analysis after a minimum 18 months follow-up.

Methods

A single modified approach involving digastric trochanteric flip osteotomy and a modified Kocher–Langenbeck approach with anterior (n = 14) or posterior (n = 4) surgical dislocation of the femoral head, was done for one or more of following reasons: intra-articular assessment of reduction in fractures with comminution, marginal impaction and involvement of the anterior column, removal of intra-articular fragments, and confirmation of extra-articular screw placement.

Results

At a mean follow-up of 26 months (18–40 months), the 17 patients presented with a good to excellent clinical result according to the d’Aubigné score. In all subjects, anatomical reduction was achieved during surgery. The osteotomy site healed at an average of 7 weeks and all the patients recovered abductor strength at 12 weeks. One avascular necrosis occurred in a case of posterior column plus wall fracture (who presented to us after 3 weeks). No heterotopic ossification interfering with hip function was found.

Conclusion

This technique gives good exposure (especially in posterior wall, dome area, posterior fracture-dislocation with intra-articular fragments/femoral head fractures and T-fractures), preservation of abductor strength (which may be lost with excessive retraction of abductors to see dome area in classical posterior approach), reliable healing of osteotomy (in contrast to conventional trochanteric osteotomy) without risking the vascularity of femoral head.     

Outcome of unstable isolated fractures of the posterior acetabular wall associated with hip dislocation

Background

Traumatic hip dislocation with fracture of the posterior acetabular wall is associated with high rates of residual invalidity.

Methods

The records of patients who underwent surgical treatment of traumatic dislocation of the hip associated with an isolated fracture of the posterior acetabular wall from 1999 to 2009 were reviewed. There were 30 men and 12 women, who at the time of the trauma had a mean age of 42 years (range 21–65). Mean follow-up duration was 5 years (range 2–10). Pre-operative fracture evaluation was based on the classification of Judet et al. which divided this fractures into three types: type 1 is characterized by a single fracture line separating a single bone fragment from the remaining part of the posterior wall; type 2 fracture involves several fragments of the posterior wall and in type 3, a type 1 or type 2 fracture is associated with a sunk cancellous area in the acetabular wall medial to the fracture line but not affected by it, due to the shear impact of the femoral head at the time of dislocation. Clinical evaluation of the outcome was according to the criteria of Merle D’Aubigné and Postel as modified by Matta. Outcomes were divided into excellent/good and fair/poor. Since treatment was standard, data were further analyzed to assess the relative importance of age, sex, follow-up duration, sciatic nerve lesion on admission and mechanism of injury, using the Chi-square test.

Results

Full clinical recovery without sequelae or radiographic abnormalities was achieved by 10 patients, 8 with type 1 fracture and 2 with type 2 fracture. A good outcome was seen in 13 patients, 3 with type 1 fracture, 9 with type 2 fracture and 1 with type 3 fracture. Eight patients, 3 with type 2 fracture and 5 with type 3 fracture, had a fair outcome. Only follow-up ≥6 years influenced outcome significantly (p > 0.005).

Conclusion

Our conclusions in light of our experience are that in type 1 lesions, anatomical reduction and stabilization achieve excellent outcomes, both clinical and radiographic; type 2 fractures pose greater prognostic problems because their outcome is determined by the success of the reduction and fixation of a multi-fragment fracture; finally, different considerations apply to type 3 fractures, which present varying degrees of comminution and an impacted acetabular surface: their outcome depends on the quality of the anatomical and morphological restoration of acetabular congruence.     

Rationales for the Bernese approaches in acetabular surgery

Purpose

To present two new approaches to acetabular surgery that were established in Berne, and which aim at enhanced visualization and anatomical reconstruction of acetabular fractures.

Method

The trochanteric flip osteotomy allows for surgical hip dislocation, and was introduced as a posterior approach for acetabular fracture management involving the posterior column and wall. For acetabular fractures predominantly involving the anterior column and the quadrilateral plate, the Pararectus approach is described.

Results

Full exposure of the hip joint, as provided by the trochanteric flip osteotomy, facilitates anatomical reduction of acetabular or femoral head fractures and safe positioning of the anterior column screw in transverse or T-shaped fractures. Additionally, the approach enables osteochondral transplantation as a salvage procedure for severe chondral femoral head damage and osteoplasty of an associated inadequate offset at the femoral head–neck junction. The Pararectus approach allows anatomical restoration with minimal access morbidity, and combines advantages of the ilioinguinal and modified Stoppa approaches.

Conclusions

Utilization of the trochanteric flip osteotomy eases visualization of the superior aspect of the acetabulum, and enables the evaluation and treatment of chondral lesions of the femoral head or acetabulum and labral tears. Displaced fractures of the anterior column with a medialized quadrilateral plate can be addressed successfully through the Pararectus approach, in which surgical access is associated with minimal morbidity. However, long-term results following the two presented Bernese approaches are needed to confirm that in the treatment of complex acetabular fractures the rate of poor results in almost one-third of all cases (as currently yielded using traditional approaches) might be reduced by the utilization of the presented novel approaches.     

Der ilioinguinale Zugang bei Azetabulumfrakturen

Objective Exposure of the entire anterior column of the acetabulum and of the inner part of the posterior column. Indications Open reduction and internal fixation of fractures of the anterior wall and anterior column of the acetabulum and of fractures, which involve both columns, on the condition that the posterior column can be reduced indirectly. Contraindications Fractures of the posterior wall.Fractures of the posterior column.Factures which involve both columns where the posterior column has to be reduced directly.Fractures requiring a direct access to the acetabulum, e. g., with intraarticular fragments. Surgical Technique Exposure of the acetabular fracture through three surgical windows. First window situated between the iliopsoas and the iliac crest, second window between the inguinal vessels and the iliopsoas, third window betwen the spermatic cord and the inguinal vessels. Indirect reduction of the fracture. Orientation through anatomic landmarks and image intensifier. Fixation of fracture with lag screws (iliac crest) and a long curved plate placed on the iliopectineal line. Results In a 9-year period, 61 patients with acetabular fractures were treated with a stabilization through an ilioinguinal approach. 27 fractures were classified as “simple” and 34 as “combined”. Intraoperative complications related to the approach were four (6.6%) secondary motoric neurologic damages, one thrombosis of the external iliac artery, and a thrombosis of the iliac veins. One fourth of the patients had paresthesias in the area of the lateral femoral cutaneous nerve. Of 38 patients examined after an average of 23 months, 85.4% obtained an excellent or good result using Merle d'Aubigné &; Postel score.     

Newly modified Stoppa approach for acetabular fractures

Purpose

We present our experience of using a newly modified Stoppa approach combined with a lateral approach to the iliac crest in patients with acetabular fractures in reference to fracture reduction and fixation, technical aspects, and the incidence of complications.

Methods

We used a consecutive group of 29 adult patients with acetabular fractures treated operatively with a newly modified Stoppa approach between 2009 and 2011. The newly modified Stoppa approach was performed to fix the acetabular fractures with main anterior displacement and the anterior and lateral parts of the pelvis. This approach was combined with a lateral approach on the iliac crest for fractures of the iliac wing.

Results

All the patients were followed up for at least 1.5 years. Of the 29 patients, ten anterior column, two associated both column, seven anterior column with posterior hemi-transverse, four transverse, and six T-type fractures. The average blood loss was 950 mL, and average operative time was 155 minutes. Anatomic or satisfactory reduction was achieved in 96 % of the acetabular fractures. Two patients had mild symptoms of the lateral femoral cutaneous nerve and improved within three months.

Conclusions

The newly modified Stoppa approach provides excellent visualization to the anterior column, quadrilateral surface and permits good postoperative results for treatment of acetabular fractures. We considered this technique as a viable alternative for the ilioinguinal approach when exposure of the anterior acetabulum is needed.     

Modified Kocher-Langenbeck approach in combined surgical exposures for acetabular fractures management

Background:

Displaced fractures of the acetabulum are best treated with anatomical reduction and rigid internal fixation. Adequate visualization of some acetabular fracture types may necessitate extensile or combined anterior and posterior approaches. Simultaneous anterior iliofemoral and posterior Kocher-Langenbeck (K-L) exposures with two surgical teams have also been described. To assess whether modified Kocher-Langenbeck (K-L) approach can substitute standard K-L approach in the management of elementary acetabular fractures other than the anterior wall and anterior column fractures and complement anterior surgical approaches in the management of complex acetabular fractures.

Materials and Methods:

20 patients with transverse and associated acetabular fractures requiring posterior exposure were included in this prospective study. In 9 cases (7 transverse, 1 transverse with posterior wall, and 1 posterior column with posterior wall), stabilization was done through modified K-L approach. In 11 cases (3 transverse and 8 associated fractures), initial stabilization through iliofemoral approach was followed by modified K-L approach.

Results:

The average operative time was 183 min for combined approach and 84 min for modified K-L approach. The postoperative reduction was anatomical in 17 patients and imperfect in 3 patients. The radiological outcome was excellent in 15, good in 4, and poor in one patient. The clinical outcome was excellent in 15, good in 3 and fair and poor in 1 each according to modified Merle d’Aubigne and Postel scoring system.

Conclusion:

We believe that modified K-L approach may be a good alternative for the standard K-L approach in the management of elementary fractures and associated fractures of the acetabulum when combined with an anterior surgical approach. It makes the procedure less invasive, shortens the operative time, minimizes blood loss and overcomes the exhaustion and fatigue of the surgical team.     

Associated lesions in posterior wall acetabular fractures: not a valid predictor of failure

Background

The general outcome of posterior wall acetabular fractures is still the source of discussion. Posterior wall fractures are recognized throughout the literature as being difficult to treat. The aim of the present study was to analyze in our own patients the relevance of the classical prognostic criteria for the outcome of isolated posterior wall fractures and those with associated lesions.

Materials and methods

A prospective cohort of 33 consecutive patients treated operatively between 1996 and 2006 in a single level 1 trauma center for a posterior wall fracture of the acetabulum was analyzed retrospectively. Included were posterior wall acetabular fractures or associated posterior wall fractures, such as the combinations of posterior column with posterior wall, transverse with posterior wall, or T-shaped fracture with posterior wall fracture. Outcome measurement of the postoperative survival of the hip joints until the primary outcome reoperation (total hip replacement or fusion) and secondary outcome diagnosis of symptomatic osteoarthritis were performed.

Results

Twenty-six of the 33 patients with posterior wall fractures also had a dislocated joint. Twelve had isolated and 21 associated fractures. Six patients were reoperated with a THA (four patients within 2 years and one after 10 years), and one arthrodesis was done to treat a hematogenous septic arthritis in a degenerative hip joint. Secondary arthritis was observed in 10 patients.

Conclusions

No difference was found between the outcome in cases of isolated posterior wall acetabular fracture and the outcome in those with associated lesions. The classical prognostic criteria were not found to be relevant to the outcome for our group.     

Die offene Therapie des femoroazetabulären Impingements

Objective

Elimination of an intraarticular femoroacetabular impingement conflict. Creation of a pain-free, normal range of motion of the hip.

Indications

Femoroacetabular impingement of any type (cam/pincer) and any localization (anterior/posterior).

Contraindications

Absolute: advanced hip osteoarthritis, local infections around the hip. Relative: excessive acetabular retroversion with deficiency of the posterior wall.

Surgical Technique

Lateral decubitus position. Straight lateral incision centered over the greater trochanter. Entering of the Gibson interval. Digastric trochanteric osteotomy with protection of the medial circumflex femoral artery. Opening of the interval between the piriformis and the gluteus minimus muscle. Z-shaped capsulotomy. Dislocation of the femoral head. Detachment of the labrum. Trimming of the excessive acetabular rim. Refixation of the labrum. Creation of a sufficient femoral head-neck offset. Suture of the capsule. Refixation of the trochanter.

Postoperative Management

During hospital stay, intensive mobilization of the hip joint using a continuous passive motion machine with a maximum flexion of 90°. No active abduction and passive adduction over the body’s midline. Maximum weight bearing 10–15 kg for 6 weeks. Subsequently, first clinical and radiographic follow-up. Deep venous thrombosis prophylaxis until full weight bearing.

Results

Short- and mid-term results showed an improvement of the postoperative clinical score (Merle d’Aubigné Score) in 95% of all patients, depending on the individual degenerative joint alterations at the time of surgery. Good to excellent results were obtained in 91% of all cases. Cumulative 5-year survival was 91% (endpoint total hip arthroplasty or poor Merle d’Aubigné Score). Long-term results are not available yet.     

Total hip replacement arthroplasty with Mallory-Head system—minimum ten-year follow-up results

Purpose

The purpose of this study was to assess the clinical and radiographic results of a total hip arthroplasty with the double tapered Mallory-Head system.

Methods

The clinical and radiographic results of a consecutive series of 81 total hip replacements in 75 patients were reviewed 10–15?years (average 11.4?years) postoperatively. The patients’ underlying conditions were avascular necrosis in 46 hips (57?%), osteoarthritis in 12 hips (15?%), RA in nine hips (11?%), and others. Clinical results were evaluated based on the modified Harris hip score and modified Merle d’Aubigné-Postel score. A radiographic analysis was performed.

Results

The average modified Harris hip score improved from a preoperative score of 56 points to a postoperative 92 points. The average modified Merle d’Aubigné-Postel score was 15 points at the latest follow up, and 55 hips (68?%) were classified as the clinical grades of excellent or good results. One acetabular component was revised because of loosening, and one was revised for recurrent dislocation.

Conclusion

The clinical and radiological evaluations of the total hip replacements using the Mallory-Head system showed good results.     

Osteosynthese und Pfannenwechsel bei periprothetischer Azetabulumfraktur über einen Kocher-Langenbeck-Zugang

Objective

Reconstruction/stable fixation of the acetabular columns to create an adequate periacetabular requirement for the implantation of a revision cup.

Indications

Displaced/nondisplaced fractures with involvement of the posterior column. Resulting instability of the cup in an adequate bone stock situation.

Contraindications

Periprosthetic acetabulum fractures with inadequate bone stock. Extended periacetabular defects with loss of anchorage options. Isolated periprosthetic fractures of the anterior column. Septic loosening.

Surgical technique

Dorsal approach. Dislocation of hip. Mechanical testing of inlaying acetabular cup. With unstable cup situation explantation of the cup, fracture fixation of acetabulum with dorsal double plate osteosynthesis along the posterior column. Cup revision. Hip joint reposition.

Postoperative management

Early mobilization; partial weight bearing for 12 weeks. Thrombosis prophylaxis. Clinical and radiological follow-ups.

Results

Periprosthetic acetabular fracture in 17 patients with 9 fractures after primary total hip replacement (THR), 8 after revision THR. Fractures: 12 due to trauma, 5 spontaneously; 7 anterior column fractures, 5 transverse fractures, 4 posterior column fractures, 1 two column fracture after hemiendoprosthesis. 5 type 1 fractures and 12 type 2 fractures. Operatively treated cases (10/17) received 3 reinforcement ring, 2 pedestal cup, 1 standard revision cup, cup-1 cage construct, 1 ventral plate osteosynthesis, 1 dorsal plate osteosynthesis, and 1 dorsal plate osteosynthesis plus cup revision (10-month Harris Hip Score 78 points). Radiological follow-up for 10 patients: consolidation of fractures without dislocation and a fixed acetabular cup. No revision surgeries during follow-up; 2 hip dislocations, 1 transient sciatic nerve palsy.

     

Surgical treatment of marginal osteochondral impaction in acetabular fractures

Purpose

Clinical and radiological evaluation of the results of the technique of elevation and grafting of osteochondral marginal impaction fragment of posterior wall acetabular fractures.

Methods

Twenty patients available for this study had fracture acetabulum with marginal impaction fragment. Elevation, reduction and bone graft impaction of the defect were the technique in all cases. Follow-up was at least for 1 year. Evaluation of patient was done clinically by modified Merle d’Aubigné and Postel score and radiologically by Matta’s criteria of reduction quality and that of radiological hip evaluation. Ficat criteria for avascular necrosis and Brocker criteria were used for evaluation of heterotopic ossification.

Results

Radiologically, according to the Matta’s criteria of reduction quality there were anatomic reduction in 16 patients (80%) and satisfactory reduction in 4 patients (20%). Clinical assessments based on modified Merle d’Aubigné and Postel score include 4 (20%) excellent scores, 12 (80%) good scores, 3 (15%) fair results and poor in one patient who had revision by total hip replacement.

Conclusion

Diagnose of marginal impaction fragment preoperatively makes operative technique by elevation, reduction, bone graft packing and fixation mandatory to obtain anatomic reduction and favorable outcome. This technique should be completed before final fixation of the main fracture acetabulum.

     

The use of a structural free iliac crest autograft for the treatment of acetabular fractures

Introduction

Bone and cartilage deficits in the posterior acetabular wall are severe complications resulting from the unsuccessful management or delayed treatment of acetabular fracture. This potentially disastrous condition cannot be treated reliably with the use of reconstruction plates and screws alone. Therefore, this technical report describes a modified anatomical reconstruction method that uses a structural iliac crest autograft and an acetabular tridimensional memory alloy fixation system (ATMFS) to treat late-stage deficits in the posterior wall of the acetabulum. This paper also describes a clinical study of 22 patients with an average of 6.3 years follow-up to evaluate the clinical outcomes of this method.

Methods

Twenty-two patients, who had an acetabular reconstruction between January 2000 and December 2011 that used a structured free iliac crest autograft to treat late-stage bone and cartilage deficits in the posterior acetabular wall were followed annually with clinical and radiographic evaluations. The average age of the patients was 36.4 years at the time of the procedure, and the average time of follow-up was 6.3 years.

Results

None of the patients in this study lost reduction after surgery, and there were no cases of implant failure. Radiographic analysis using Matta’s X-ray evaluation criteria were excellent in eleven cases, good in eight, and fair on three. The Merle D’Aubigné and Postel clinical outcomes at the final follow-up were as follows: seven cases were excellent, ten cases were good, three cases were fair and two cases were poor.

Conclusions

The use of a modified iliac crest grafting and ATMFS fixation, as a biological method to reconstruct the acetabulum anatomically may offer better congruence of the joint surface and may ensure good hip joint stability during early postoperative exercise. The medium to long-term results of this method are encouraging.     

Impaction bone grafting for femoral revision hip arthroplasty with Exeter Universal stem in Japan

Objectives

The purpose of the present study was to analyze the retrospective clinical and radiographic results of femoral revision arthroplasties with impaction bone grafting performed by experienced Japanese surgeons.

Patients and methods

We investigated the radiographic and clinical records more than 2?years after the surgery in 99 hips of 93 patients. The average age was 66.3?years (36–84?years) and the average follow-up period was 5.2?years (2–13?years). The Merle d’Aubigné and Postel hip score was used for clinical assessment, and peri-operative fractures were recorded. The survival curve was estimated using Kaplan–Meier method.

Results

The mean Merle d’Aubigné and Postel hip score improved from 9.0 points to 15.2 points at the final follow-up. Augmentations for segmental defect of femoral cortices were undertaken in 55 hips. Metal or strut allograft plates were applied to 9 hips and 21 hips, respectively. Intra-operative fractures or perforations occurred in 20 hips. Re-operations of the femur were undertaken in nine hips including five post-operative femoral fractures. More than 5?mm of subsidence was observed in only 2 hips. The survival rates at 8?years after the operation were 94.8?% with femoral fractures as the end point, 93.1?% with any stem removal or exchange as the end point, and 99.0?% with aseptic stem loosening as the end point, respectively.

Conclusion

The present study showed encouraging mid-term results of impaction bone grafting for femoral revision arthroplasty by experienced surgeons in Japan. Aggressive augmentation of segmental defects and attenuated femoral shafts prevents massive stem subsidence and periprosthetic fracture.     

Shortening spinal column reconstruction through posterior only approach for the treatment of unstable osteoporotic burst lumber fracture: a case report

Study design

Case report.

Clinical question

This study reports if shortening reconstruction procedure through posterior approach only can be used in osteoporotic unstable fracture as well as post-traumatic burst fracture.

Methods

An 80-year-old female patient with unstable burst osteoporotic fracture of L1 underwent posterior approach corpectomy and shortening reconstruction of the spinal column by non-expandable cages.

Result

The surgery was uneventful, with average blood loss. Using of small profile cages has helped us to avoid root injury. Augmentation of the screw with cement and the compressive force applied to the spine column aids in obtaining a rigid construct with good alignment without any neurological complication.

Conclusion

Shortening reconstruction procedure through only posterior approach is a viable option in treating unstable osteoporotic fracture as well as post-traumatic fractures. Using non-expandable cage is advocated to avoid cage subsidence.     

Biologisch azetabuläre Defektrekonstruktion beim Hüftendoprothesenwechsel mittels „Impaction Grafting“ und azetabulärem Rekonstruktionsring

Objective

Management of acetabular bone defects Paprosky types IIa and IIb in revision hip arthroplasty by rebuilding the bone stock using impaction bone grafting, primary stable reconstruction with an acetabular reconstruction ring, and restoring the hip center of rotation to its anatomical position.

Indications

Acetabular segmental or combined structural defects in the superior acetabular dome with superior/lateral hip center migration with intact anterior and posterior columns (Paprosky types IIa, IIb).

Contraindications

Acute or chronic infections, severe acetabular bone defects preventing adequate anchorage of the prosthesis—particularly destruction of the posterior column.

Surgical technique

Modified transgluteal, lateral approach to the hip joint. Removal of the loose acetabular component. Complete circumferential exposure of the acetabular rim, while maintaining mechanical stability of the remaining bone. Preparation of the homologous spongiosa chips and reconstruction of the acetabular defect in impaction grafting technique. Implantation of the acetabular reconstruction ring and primary stable fixation with cancellous screws in the acetabular dome. Cemented fixation of a polyethylene inlay.

Postoperative management

Mobilization on 2 underarm crutches from postoperative day 1. Partial weight bearing with 20 kg for 6 weeks postoperatively. If plain radiographs show unchanged seating of the prosthesis after 6 weeks, loading can be increased by 10 kg/week until full weight bearing is achieved; thrombosis prophylaxis is continued throughout. Limitation of hip flexion to 90° during the first 6 weeks, and no adduction and forced external rotation to avoid dislocation. Avoidance of sports involving jumping and axial impact loading for 12 months. Radiologic checkups after 3, 6, and 12 months and, thereafter, every 2 years.

Results

Analysis between 2008 and 2011 involved 22 consecutive patients with a total of 23 prostheses; the mean follow-up was 38?±?11 months. Compared to the preoperative evaluation, follow-up yielded a significant improvement in the average Harris Hip Score (82.2?±?8.7 vs. 44.7?±?10.7) and the Merle d’Aubigné Score (14.6?±?1.9 vs. 7.5?±?1.3). Radiological solid osseointegration of the cup was observed in 21 cases; partial radiolucent lines were seen in 2 cases (9?%) in the zones I–III delineated by DeLee and Charnley. In 21 cases (91?%) radiographs confirmed no measurable migration or displacement of the acetabular component and the bone graft was determined to be incorporated on the basis of osseous consolidation within the grafted area in 20 cases (87?%). During follow-up 3 prosthesis (13?%) required revision.     

Are Quadrilateral Surface Buttress Plates Comparable to Traditional Forms of Transverse Acetabular Fracture Fixation?

Background

Several construct options exist for transverse acetabular fracture fixation. Accepted techniques use a combination of column plates and lag screws. Quadrilateral surface buttress plates have been introduced as potential fixation options, but as a result of their novelty, biomechanical data regarding their stabilizing effects are nonexistent. Therefore, we aimed to determine if this fixation method confers similar stability to traditional forms of fixation.

Questions/purposes

We biomechanically compared two acetabular fixation plates with quadrilateral surface buttressing with traditional forms of fixation using lag screws and column plates.

Methods

Thirty-five synthetic hemipelves with a transverse transtectal acetabular fracture were allocated to one of five groups: anterior column plate + posterior column lag screw, posterior column plate + anterior column lag screw, anterior and posterior column lag screws only, infrapectineal plate + anterior column plate, and suprapectineal plate alone. Specimens were loaded for 1500 cycles up to 2.5x body weight and stiffness was calculated. Thereafter, constructs were destructively loaded and failure loads were recorded.

Results

After 1500 cycles, final stiffness was not different with the numbers available between the infrapectineal (568 ± 43 N/mm) and suprapectineal groups (602 ± 87 N/mm, p = 0.988). Both quadrilateral plates were significantly stiffer than the posterior column buttress plate with supplemental lag screw fixation group (311 ± 99 N/mm, p < 0.006). No difference in stiffness was identified with the numbers available between the quadrilateral surface plating groups and the lag screw group (423 ± 219 N/mm, p > 0.223). The infrapectineal group failed at the highest loads (5.4 ± 0.6 kN) and this was significant relative to the suprapectineal (4.4 ± 0.3 kN; p = 0.023), lag screw (2.9 ± 0.8 kN; p < 0.001), and anterior buttress plate with posterior column lag screw (4.0 ± 0.6 kN; p = 0.001) groups.

Conclusions

Quadrilateral surface buttress plates spanning the posterior and anterior columns are biomechanically comparable and, in some cases, superior to traditional forms of fixation in this synthetic hemipelvis model.

Clinical Relevance

Quadrilateral surface buttress plates may present a viable alternative for the treatment of transtectal transverse acetabular fractures. Clinical studies are required to fully define the use of this new form of fixation for such fractures when accessed through the anterior intrapelvic approach.