Acetabulum fractures in the elderly, reconstruction or replacement ?

1. Summary

The increasing occurrence of acetabulum fractures in the geriatric population is examined based on the author's personal cohort of 255 acetabular fractures treated surgically. Among 45 patients older than 60, fractures involving medial protrusion of the femoral head were the most frequent, unlike in younger patients where posterior wall or column fractures predominated. Nonoperative treatment is not suitable for active geriatric patients. For ORIF of medial protrusion fractures, less invasive approaches such as the Stoppa or endopelvic exposure should be preferred. Special anatomic plates designed for endopelvic exposure are particularly suited to osteoporotic bone. Good functional outcomes depend on the anatomical restoration of the anterior column and quadrilateral plate. Primary Hip Arthroplasties combined with ORIF is an effective treatment for specific fracture patterns known for their poor long-term prognosis after ORIF alone. Fractures involving the posterior wall have problematic long-term outcomes even after anatomic reduction. Primary arthroplasties accelerate functional recovery. Our long-term results after ORIF combined with primary THR in selected cases were favorable and were in accordance with recent literature reports.

Fractures of the acetabulum are becoming more frequent due to various factors such as exposure to sports activities at higher ages. In the classic series of Judet and Letournel relating results after primary open reduction and internal fixation (ORIF) in acetabulum fractures published more than 30 years ago, primary ORIF was established as the golden standard of care.¹

Less invasive surgical approaches, specifically designed surgical instruments and implants, 3D image analysis, improved anesthesiologic techniques have widened the spectrum of patients who can benefit from primary surgical treatment of these complex fracture patterns.

Acetabular fractures are primarily caused by the traumatic impaction of the femoral head into the hip joint. Two typical mechanisms are involved.

• 1.Posterior Fracture-Dislocation: Induced by a force transmitted through the femur axis with the hip in flexion, leading to posterior wall or column fractures, T-Type fractures, or associated transverse plus posterior wall fracture patterns (Judet-Letournel classification).
• 2.Medial Protrusion: Caused by a medial displacement of the femoral caused by an impact on the greater trochanter, often from a fall, resulting in anterior column, both column, anterior column plus posterior hemi-transverse, or transverse fracture patterns.

Functional outcomes of acetabular fractures depend on the restoration of joint congruency. Posterior wall fractures have poorer long-term outcomes, with rates of early osteoarthritis as high as 40 % in Letournel's series.¹ Medially displaced fractures have better outcomes if good reduction is achieved during primary ORIF. Similar findings were reported by Matta and others,² who noted up to 32 % failure rates in posterior wall fractures, especially in older patients. In these series, the majority of patients were young and active and older patients, were less frequent.

The reluctance to perform these complex procedures in more fragile and potentially osteoporotic patients may have introduced a bias in the age-related selection of patients. Older patients were less frequently considered for ORIF. Matta, Mears & others^2,3 noted that the rate of perfect reductions was lower in these patients. They also reported that even if anatomic or near-anatomic reductions were obtained, higher rates of early as well as late complications were observed in older patients.

In our personal consecutive series of 186 ORIF for acetabulum fractures with a minimum follow-up of two years or more, we found that the rate of late osteoarthritis was clearly higher in fractures involving the posterior wall as well as T-Type fractures (Fig. 1). Tannast⁴ reported the same observation in a series of 810 patients. The same findings, with elderly patients were also reported by Butterwick & al.⁵

Fig. 1.

Fractures of the acetabulum involving a posterior displacement of the femoral head and wall are known to be associated significantly worse long-term outcomes in young as well as older patients. Best outcomes are observed after medially displaced fracture types in all age groups. Anterior wall fractures, although very uncommon are also linked to poor long-term outcomes.

2. Age-related distribution of acetabular fractures

The demographics of acetabulum fractures in elderly patients is changing. Most recently published series report two distinct findings in the epidemiology of such fractures. First, fractures of the acetabulum are becoming more frequent in patients over the age of 60. The fracture pattern distribution in the geriatric and/or osteoporotic patients is also different. Contrary to younger patients, in which fractures involving the posterior wall are more frequent, fractures involving a medial displacement, such as associated anterior column plus posterior hemi-transverse or both column fractures are clearly dominant in older patients.⁵

These findings were confirmed in our personal case series. We analyzed a continuous cohort of acute acetabulum fractures in 255 patients who required primary surgical treatment between 1991 and 2014 at our institution. We noted that the large majority of patients between 1991 and 2004 were aged between 20 and 50 years. After 2004 acetabulum ORIF had become most frequent in older patients, particularly in the age group between 50 and 69 years of age (Fig. 2). In our cohort of 255 patients 45 patients were over the age of 60.

Fig. 2.

In a consecutive cohort of 255 acetabulum fractures treated surgically within 3 weeks, the age distribution has changed over the years. Until 2004, younger patients were most frequent. After 2005, we observed an increase in the number of patients older than 60.

Our second finding was that in the group of patients older than 60 (Fig. 3), medially displaced fracture types were the most frequent, whereas fracture patterns involving the posterior wall were unusual in elderly patients. Posterior fractures remained the most common pattern in patients below 60 years of age.

Fig. 3.

In the author's series of 255 acetabulum fractures treated surgically within 3 weeks, 45 patients were aged 60 or older. The distribution of their fracture patterns, according to the Judet-Letournel classification clearly differs from the distribution observed in younger patients.

Choice of treatment for medially displaced, protrusion acetabular fractures in older patients:

Based upon these previous observations, we believe that ORIF should remain the preferred option in elderly or osteoporotic patients presenting with protrusion acetabulum fractures involving medial displacement.

The technically demanding classic ilio-inguinal exposure used to be the standard approach for the ORIF of medially displaced fractures.¹ Using this exposure, the lateral or medial windows were used to obtain reduction and fixation of the anterior column using a plate resting on the superior aspect of the pelvic brim to control the vertical displacement. The medial window would then be used to control the medial displacement of the posterior column or quadrilateral surface. Long screws introduced through the plate using the middle or lateral windows were used to fix the posterior column. Screw fixation of the posterior column alone proved less efficient to control medial displacement in osteoporotic bone. The solution known as “buttress plates”, as recommended by Mast & al.⁶ appears biomechanically superior, but still relies on the use of the ilioinguinal exposure. We reported our personal experience with the use of “buttress plates”, as described by Mast & al. In a series of 13 patients followed for over one year with good results in 85 % of our patients.⁷

Two significant developments have revolutionized the treatment of elderly and/or osteoporotic anterior fractures of the acetabulum.

At first, the « Modified Stoppa Approach », introduced in 1994 b y Cole & Bolhofner^8,9 provides a less invasive exposure with excellent access to the medial aspect of the iliac bone and quadrilateral surface while avoiding the need to dissect delicate neurovascular structures such as the external iliac vessels, femoral or femoro-cutaneous nerves. The use of the so-called endopelvic or Modified Stoppa approach has become our preferred exposure for the fixation of such fracture patterns. If required, an associated Iliac exposure may extend exposition to the medial aspect of the iliac wing. The association of these both approaches remains less invasive and less technically demanding than the classic ilio-inguinal approach. The Stoppa approach also provides a better control for the reduction of the quadrilateral surface and posterior column.¹⁰

The second recent development is the recent availability of special anatomic plates¹¹ combining supra-pectineal support, as well as medial buttress to the quadrilateral surface and posterior column. These anatomic plates are becoming the standard for the fixation of osteoporotic protrusion acetabular fractures. Those plates may be inserted through the less invasive endopelvic approach. Recent studies reporting good results using these new implants are beginning to appear in the literature.¹²

Considering the favorable long-term prognosis after ORIF of medially displaced, protrusion acetabulum fractures even in osteoporotic or elderly patients, open reduction and internal fixation remains our preferred choice for anterior column, both columns, and anterior column plus posterior hemi-transverse fractures, in younger as well as in older patients. The use of the endopelvic, or modified Stoppa exposure has become our standard approach for the fixation of these fractures. The use of custom bent « buttress plates » is no longer required. More efficient solutions such as the anatomic « Suprapectineal Plates ®» initially introduced by the Stryker company in 2010 (Fig. 4, Fig. 5) provide efficient control of medial, as well as vertical displacement in these fractures. Similar implants adding improved control of the posterior column fixation are becoming available.

Fig. 4.

A and B: 64 Years old patient presenting with a Both Columns fracture. The fracture was reduced and fixed using a Stryker ® Supra-Pectineal reconstruction plate.

Fig. 5.

A-B-C: This 78 old active lady was violently hit, as a pedestrian, by a cyclist. On admission, patient presented with multiple wounds, commotio cerebri with loss of consciousness, open elbow fracture and a displaced anterior column fracture of her right acetabulum. Patient developed a duodenal ulcer at day 4 and ORIF of her acetabulum was delayed until day 9. ORIF was performed through a 10 cm Pfannenstiel incision and Stoppa approach. A Suprapectineal anatomic plate was used for reduction and fixation. Figures A&B At one year, patient was active and symptom free Fig. 5C.

3. Choice of treatment for posteriorly acetabular fractures involving posterior displacement in older patients

In geriatric patients, avoiding secondary procedures and accelerating recovery is crucial. Less experienced surgeons, less aware of the high risk of late failures with these fracture types, may feel comfortable with the ORIF of posterior wall fracture patterns. The risk of late failure is particularly high in osteoporotic geriatric patients, even after perfect anatomic reduction. The real cause of such mediocre results is not known. Whether such poor outcomes are due to an avascular head necrosis, or necrosis of the posterior wall is not known.

It has been shown that the functional outcome of secondary hip arthroplasties after failed primary acetabulum ORIF is significantly worse than after primary THR.¹³

These arguments support the choice of a primary hip replacement in association with the open reduction and fixation for posterior fractures. Cofactors such as presence of preexisting osteoarthritis, associated traumatic femoral head lesions, sub-chondral impactions, delayed surgery with incongruent consolidation are other arguments in favor of a primary THR. Opting for a primary THR for posterior fractures does not increase the duration of the surgery, nor does it increase its complexity, risk of heterotopic bone or blood loss. Another advantage with ORIF + THR through the posterior approach, as opposed to anterior exposures, is that the classic Kocher-Langenbeck exposure required for the ORIF does not need to be extended for the placement of the arthroplasty.

The option of primary arthroplasty in elderly posterior acetabular patterns is becoming more and more accepted. Primary arthroplasty in geriatric patients may as well be considered in other fracture types in which the prognosis of primary ORIF is questionable.

Gary &al.,¹⁴ in a multicenter survivorship study of 454 acetabular fractures in patients aged 60 or older observed that patients selected for a primary arthroplasty had a lower rate of mortality than those treated with primary ORIF.

Lin & al.¹⁵ reported a series of 33 acute THR + ORIF in selected fracture patterns followed for 5 years. A posterior wall fracture was present in 72 % of their patients and good or excellent outcomes were reported.

Boraiah & al.¹⁶ reported on a cohort of 420 displaced acetabulum fractures in which primary ORIF + THR was performed in 21 patients averaging 71 years of age. A posterior wall fracture was present in 15 of these 21 patients. Fracture healing without cup loosening was observed in all patients at one year follow-up.

Some authors rely on the « fix and replace » option in elderly patients even in medially displaced fracture patterns. A primary THR was used in a series of 57 patients ranging from 60 to 95 years of age published by Hislop & al. In 2022.¹⁷ In this series, 67 % of fractures were classified as associated anterior column plus posterior hemi-transverse. Their implant survival rate was 90 % at one year.

Most authors use plates and screws to reduce and fix the fracture prior to the introduction of a cementless cup. The approach used by Mouhsine & al. Is different, this author reports a series of 11 patients in which a figure of 8 cable construct was used to achieve the reduction and fixation prior to the introduction of the cup.¹⁸ In his series of 11 patients, 8 fractures were classified as type T.

In our consecutive cohort of 255 patients primary acetabulum ORIF, 45 patients were over the age of 60. Of those, 16 patients averaging 64 years of age were treated with a primary Total Hip Replacement associated with ORIF of the fracture. Of those 16, 13 patients presented with a fracture involving the posterior wall of the acetabulum.

4. Author's operative technique for posterior geriatric acetabulum fractures

Besides the routine anesthesiologic preoperative workup, we rely on an AP pelvis standard radiographhy as well as a pelvic CT. 3D images are analyzed on a personal computer screen using the Osirix radiologic viewer.¹⁹

Patients are placed on the operation table in the lateral decubitus position. A posterior Kocher-Langenbeck approach is performed in a classic manner. The sciatic nerve is identified and protected and the posterior capsule is opened. No attempt at fracture reduction should be undertaken at this stage. The femoral head is dislocated and the femoral neck is cut using an oscillating saw. Head and neck are resected and will be kept as potential bone graft if needed. Removal of the head and neck greatly facilitates fracture reduction and exposure, as it releases traction on the gluteal musculature. One or two 3.5 mm contoured reconstruction plates are used for fixation by bridging the posterior column fracture and providing posterior buttress of the posterior wall. Once stable fixation of the column and wall is obtained, the acetabular cavity is reamed using a standard spherical reamer.

Additional implants such as Muller acetabular reinforcement rings are not routinely used for posterior fracture types. Such implants may however be useful in medially displaced or comminuted fracture patterns.

Uncemented, dual mobility acetabular cups are our preferred choice, in order to reduce the risk of secondary implant dislocation. After capsule closure, reinsertion of the external rotators on the greater trochanter, the integrity of the sciatic nerve is controlled and the wound is closed on a suction drain kept in place for 24 h. Prophylactic NSAID's (Ibuprofen 3 × 400 mg daily) are administered for a duration of up to 10 days to prevent heterotopic bone formation. Patients are mobilized out of bed at day one and allowed to ambulate, limiting weightbearing to 10–15 kg for 8–12 weeks.

At one year follow-up, in our series of 16 primary THR + ORIF, results were good or excellent in 11 patients. Complications requiring surgical revision were 1 infection and 1 dislocation.

One late deep infection occurred at two years followup in a 65 years old man suffering from liver cirrhosis, diabetes and leg ulcers who initially presented with an anterior plus posterior hemi-transverse fracture. ORIF + THR through a posterior approach was delayed for two months due to his general condition. An acetabular reinforcement ring was used. Postoperative local and functional recovery was satisfactory. At 18 months, the patient's general condition deteriorated and he developed a deep Enterobacter & Pseudomonas infection of his hip that required resection arthroplasty.

Two patients presented with secondary THR dislocations. Dual mobility cups had not been used in these two patients. In one 63 years old man, a regular acetabular cup and 36 mm head component were implanted one week after a posterior wall fracture. Recurrent dislocations required the replacement of the acetabular cup with a dual mobility cup at 6 months. Followup was uneventful thereafter. The second patient, a 69 years old man who presented with a Type T fracture had been treated using a posterior approach and a regular cup with 28 mm head at one week. He suffered two posterior dislocations, one at 1 month and the second at 4 months. No revision was undertaken and the followup was uneventful thereafter. Heterotopic ossifications were observed in 3 patients causing a partial limitation of the range of motion, but did not require surgical revision.

5. Conclusions

In our series of 255 surgically treated acetabulum fractures we found that these fractures are becoming more frequent, due in part to an increase in the occurrence of these fractures in active geriatric patients. In this age group, fracture pattern distribution is different than in the younger patient group. Fractures involving a medial protrusion of the femoral head, anterior column, both columns, or associated ant. Column plus posterior hemitransverse are the most frequent, whereas patterns involving the posterior column or wall are less frequent. Based upon published reports as well as the author's opinion, ORIF remains our preferred technique for the typical medial protrusion fracture pattern in geriatric patients, with satisfactory late results in our experience, as well as in reported series. In less frequent geriatric fracture patterns involving posterior displacement, we favor the acute ORIF associated with primary arthroplasty using uncemented dual mobility cups. Reported results as well as our personal long-term results using “fix and replace” option are satisfactory. We believe that the choice of a combined ORIF & THR also remains an option in geriatric patients in some particular situations such as associated destruction of the femoral head, subchondral impaction, excessive comminution or delayed fixation, situations which would obviously darken the prognosis of ORIF alone.

Author statement

This manuscript which was written by myself reports on a continuous series of patients treated at the university hospital Geneva Switzerland.

This material is original and has not been submitted or published elsewhere. There is no ethical or compliance issues related to this work.