Fix and replace technique in elderly acetabular fractures

INTRODUCTION

Acetabular fractures in the elderly are usually secondary to falls from their own height (fragility fractures).^[1,2] The actual incidence over 60 years old is 3 in 100,000 habitats.^[3] The current incidence is 2.4 times higher compared to the 1980s due to the aging of the general population.^[3] To a lesser extent, it can occur secondary to road traffic accidents, mainly as pedestrians.^[1] Associated injuries are present in 29% of the cases,^[1] with increasing morbidity and mortality.

The gold standard treatment in acetabular fractures continues to be open reduction and internal fixation (ORIF), even in the elderly,^[4] but results are variable. Postoperative joint congruence is a critical factor for outcomes; with optimal reductions (displacement of <2 mm), there is a 13% risk of post-traumatic osteoarthritis (OA).^[5] On the other hand, suboptimal reductions (displacement of >2 mm) lead to disappointing results, primarily due to a probability of 44% for post-traumatic OA.^[5] Subsequent treatment includes conversion to a delayed (>3 months) total hip replacement (THR) in 6–28%,^[6] or resection arthroplasty, with lower functional outcomes compared to THR for primary OA.^[7,8]

As in other geriatric fractures, the ideal approach includes a multidisciplinary group to identify fragility characteristics and optimize the bioburden of comorbidities.^[9-11] Furthermore, identifying procedures allow less surgical time with an early full weight bearing,^[12,13] as had been proposed for hip fractures.^[14,15] Since the last two decades, the “fix and replace” technique has increased in popularity.^[9] There is an increase in publications favoring acute THR for certain acetabular fractures, including better functional scores, fewer thrombotic events, decubitus ulcers, and pulmonary complications.^[4,16-22]

The literature about the “fix and replace” technique is increasing. This publication aimed to review the available literature.

INDICATIONS

The treatment of the elderly is complex because of their own medical and frail status, associated with bad bone quality. Surgeons must initiate a multidisciplinary approach to determine the physiological reserve and the probability of early complications and death.

The main indications for acute THR in acetabular fractures are: Displaced intra-articular fractures with surface comminution (>40%),^[19-23] subchondral impaction in the support zone,^{[18,20,21,23-25]} irreducible articular comminution,^[26] cartilage injuries or fracture of the femoral head and/or associated femoral neck fractures, ^{[19,20,21,25-28]} and pre-existing hip OA or avascular necrosis.^{[19,20,22,26,29]}

The predictors of bad outcomes for ORIF only in acetabular fracture are: Older than 40 years,^[17] osteoporosis,^[26] initial displacement of articular surface >20 mm,^[17] anterior hip dislocation and posterior wall fracture,^[17] and non-anatomic reduction of the joint surface with incongruity >2 mm or the presence of subchondral impaction (“Gull sign”).^[5,18]

DIAGNOSTIC IMAGING AND CLASSIFICATION

With high clinical suspicion, pelvic trauma radiographs and additional Judet projections are requested. Acetabulum fractures must be characterized and classified. Associated bone injuries are ruled out (proximal femur or pelvis fracture) [Figure 1]. Ideally, complex fractures should undergo a computerized tomography (CT) scan with three-dimensional reconstruction to decide if treating with ORIF or the “fix and replace” technique is possible.

Close

Figure 1:

Bilateral acetabular fractures in a 68-year-old male. (a) AP projection. (b and c) Judet projections. Right hip: Important subchondral impaction. Left hip: Extension to the quadrilateral plate, medial displacement of the left femoral head, and associated femoral neck fracture.

Export to PPT

According to Judet and Letournel’s classification, in the elderly, the majority of injuries are associated with pattern fractures (57%).^[7] The most frequently associated pattern was the anterior column with posterior hemitransverse (16–19%).^[26,30] The posterior wall fracture was the most common elementary pattern (14–19%).^[26,30] Ferguson et al.^[1] found a type of displacement pattern consisting of an anterior column fracture with medial displacement of the quadrilateral plate with comminution and marginal subchondral impaction, as shown in [Figure 1]; radiographs of a 68-year-old patient treated for a bilateral acetabular fracture. The femoral head was involved in 20% of the cases.^[3]

In conclusion, displaced fractures of the anterior column (anterior column, anterior column with posterior hemi transverse, and two columns with anterior wall) were associated with displacement of the quadrilateral plate, impaction of the support zone, and antero central dislocation of the femoral head.^[3,7] In contrast, posterior wall fractures tended to be comminuted with marginal impaction and posterior hip dislocation.^[3,7]

APPROACHES

Depending on the involvement of the acetabulum, the approach should be chosen. In elementary posterior patterns or associated with a non-displaced anterior component, posterior approaches, such as Kocher Langenbeck (K-L), might be performed.^[4,19] An anterior approach, like Smith Petersen or Levine approaches, is elected in fractures with displacement of the anterior column/wall, with a minimal posterior part.^[3,31] When the medial displacement of the quadrilateral plate is presented, intrapelvic access that allows an anterior visualization of the acetabulum and intrapelvic fracture management will be a valid option,^[1,31] or double approaches could be used, including a modified Stoppa^[25,30] or ilioinguinal^[30,32,33] approaches associated with a K-L or Smith Petersen approaches, as shown in [Figure 2].

Close

Figure 2:

Planning of the approach for the left hip. The intrapelvic modified Stoppa approach was planned for the reduction of the quadrilateral plate, and the Smith Petersen approach was planned for total hip replacement.

Export to PPT

In a systematic review of the “fix and replace” technique, approximately 85% of cases could be solved through a single approach. The K-L was the most used approach, followed by ilioinguinal.^[34] In combined approaches, K-L plus modified Stoppa was used 3% of the time, and ilioinguinal and K-L combination was employed in 2.9% of cases.^[32]

ACETABULAR RECONSTRUCTION

A complete analysis of the CT scan is performed to define stable bone at the subchondral level in the anteroinferior iliac spine and posteroinferior acetabulum because these are the zones that fix the cup.^[4,30,35] If fractures do not generate instability, the cup could be applied without needing ORIF. Fractures that comprise the posterior column and anterior wall are critical for stability.^[31] Therefore, ORIF is necessary for transverse, T-type, both columns, the anterior column with posterior hemitransverse, and anterior or posterior column fractures.^[31]

In the “fix and replace” technique, an anatomical reduction of the acetabular fracture is not mandatory. Adequate contact between bone fragments should be guaranteed to allow secondary consolidation and create a stable construct, forming an acetabulum that allows cup fixation.^[4,25] An ORIF for the anterior column is typically performed with a 3.5 mm long reconstruction plate on the pelvic brim, with screws between 3.5 mm or 7.3 mm in anterior to the posterior direction for fixation of the column;^[31] for posterior fixations, 3.5 mm reconstruction plates are used to “span” the posterior column and posterior wall.^[4,32] It is important to remember that ORIF implants should not interfere with the acetabular reamers or with the screws for cup fixation. [Figure 3] shows the reduction of the anterior column and fixation with two reconstruction plates.

Close

Figure 3:

Intraoperative fluoroscopic images of the left hip. (a) Direct reduction of the quadrilateral plate. (b) The reduction of the anterior column was fixed with two reconstruction plates and a reamer cup in position.

Export to PPT

On a based analysis of CT scans, Marmor et al.^[35] reported that bone corridors available for cup fixation with screws were the sciatic buttress (100%), the gluteal pillar (90%), and the anterior corridor (76%). Instead, pubic and ischial ramus corridors were only accessible in 36% and 47%, respectively. The most frequent combinations for fixation were superior pubic ramus + anterior + gluteal pillar + sciatic buttress + ischium corridors and anterior + gluteal pillar + sciatic buttress corridors.^[35] Fixation could be done with a minimum of 1–2 screws, depending on the stability of the cup to the bone and the available bone corridors; conceptually, 3–4 screws could guarantee stability.^[25] Ideally, a screw should be placed in the anterior superior pubic ramus or ischium to avoid cup abduction failure.^[4]

There are several techniques to perform cup fixation. The spectrum can vary from uncemented cups with holes to cages and cup-cages with allograft systems for cases of pelvic discontinuity and major bone defects.^[4,31]

In recent publications, better results have been found with uncemented cups with adequate press-fit fixation,^[36,37] including corticocancellous femoral head autograft application in the contained acetabular defects [Figure 4]. Bellabarba et al.^[36] compared outcomes of uncemented cups, with 97% of the cups surviving during 36 months of observation (range of 24–140 months), with similar results to THR due to non-post-traumatic OA. Malhotra and Gautam^[37] and Ranawat et al.^[38] showed adequate integration of the acetabular cups, with lower revision rates, in a follow-up of 57 months.

Close

Figure 4:

Use of autograft for augmentation of the acetabulum. (a) Left hip. Corticocancellous graft after impaction (b) Left hip. Acetabular cup in position with adequate version. (c) Right hip. A structural autograft of the femoral head was applied and fixed with screws.

Export to PPT

In non-contained defects, structural grafts of the femoral head could be applied [Figure 4]; trabecular metal could be used depending on the need.^[4,9] The cages are fixed with screws into the iliac bone and distally buried in the ischium, giving the function of bridging the defect and allowing an early weight bearing.^[4] The cup-cage system is a combination of trabeculated metal cups with different cages that are stabilized in the iliac bone with screws. Certain case series used the Burch-Schneider rings instead of trabeculated metal, reducing costs.^[39]

The use of hemipelvis reconstruction cones is indicated in frail elderly with complex osteoporotic fractures and a high risk of failure of ORIF or “fix and replace” technique. Still, they are contraindicated in pelvis discontinuity and segmental defects.^[4,40]

Surgeons must consider the challenges when facing an acute THR: Alteration of anatomy, multiple fragments that limit the primary stability, bone defects, pelvic discontinuity, and osteoporosis.^[4] Therefore, it is important to have appropriate expertise and available devices that allow complete reconstruction. The procedure could even be performed by two surgeons, a trauma surgeon and an arthroplasty surgeon, as proposed by Borg et al.^[32]

OUTCOMES

Radiologic consolidation

It was reported in 100% of the cases at 6 months.^[25,32] [Figure 5] shows the consolidation achieved at 5 months without migration of the acetabular cup, as seen in the series of Rickman et al.^[25] and Borg et al.^[32] Contrary to Mears et al.^[19] found the presence of subsidence, but without loosening during follow-up.

Close

Figure 5:

Final radiograph with complete consolidation of bilateral fractures at 5 months. (a) AP projection. (b and c) Judet projections.

Export to PPT

COMPLICATIONS

The general rate of non-fatal complications was calculated as 20% (95% CI, 13.8–27.6%)^[7] and up to 50%,^[33] most commonly were: Heterotopic ossification (HO), dislocation, thrombotic events in 4.1%,^[7] and infection of 3.8%.^[21]

The incidence of HO in the ORIF+RTH technique was reported to be 19–43%.^[7-44] A systematic review found an incidence close to 25.6% in 2394 cases, but only 5.7% presented with Class III or IV according to Brooker classification.^[5-32] Regarding the correlation between HO and approaches, the iliofemoral presented a higher rate of severe HO, close to 23.6%, while K-L was 11.6% and ilioinguinal was 1.5%.^[5] There was no benefit in prophylaxis with radiotherapy and/or indomethacin.^[5]

The reported dislocation rate was 6.1% (95% CI, 4.0–8.5%)^[5] for THR due to acetabular fracture, higher than THR for primary OA (2–4%),^[7] with an OR of 4.36; P = 0,048. The most frequent treatment was closed reduction and in cases with recurrent dislocations, revision was needed in 13.6% of cases.^[3,34] In terms of infection, there was a greater association with acetabular fractures with THR of 11%,^[43] when compared with THR for primary OA, an OR of 11.79; P = 0,028, compared to THR+ORIF.^[7,43]

Overall mortality in 366 cases of acetabular fractures was 19% (range 17.9–20.2%) at 64 months of follow-up.^[34] For ORIF, with 203 cases, the mean mortality was 15% at 47 months.^[34] In ORIF+THR, the average mortality was 13%, with a mean age of 75 years and a follow-up of 33.3 months.^[34-45] Analysis comparing ORIF versus ORIF+THR exhibits an OR of 1.15 (95% CI, 0.42 a 3.19) without a significant statistical difference (P = 0.51).^[34]

The limitation of this study is based on its nature of a narrative review of the available literature, where a statistical analysis of the exposed results is not applied.

CONCLUSION

Acetabular fractures in the elderly are increasing in number. It is important to treat polytrauma or associated injuries. As in hip fractures, early and adequate treatment, starting rehabilitation in the 1^st post-operative days with full weight-bearing of the limb, could reduce mortality and morbidity. The “fix and replace” technique is a valid alternative for the elderly, but the indications must be clear, especially in nonreconstructable fractures with subchondral impaction. It is important to carry out adequate preoperative planning to achieve an adequate reconstruction to meet the objectives of early rehabilitation. The “fix and replace” technique showed good scores in PROMs, but there is a high rate of complications, such as HO, dislocations, and infections. Studies with a larger sample included with longer follow-ups are needed.

AUTHORS’ CONTRIBUTIONS

CD conducted the literature search and wrote the initial draft. RP provided the images and revised the final draft. All authors have critically reviewed and approved the final draft and are responsible for the manuscript’s content and similarity index.

ETHICAL APPROVAL

An ethics statement is not applicable because this study is based exclusively on published literature.

USE OF ARTIFICIAL INTELLIGENCE (AI)-ASSISTED TECHNOLOGY FOR MANUSCRIPT PREPARATION

The authors confirm that there was no use of artificial intelligence (AI)-assisted technology for assisting in the writing or editing of the manuscript and no images were manipulated using the AI.