The advent of modular porous metal augments has ushered in a new form of treatment for acetabular bone loss. The function of an augment can be seen as reducing the size of a defect or reconstituting the anterosuperior/posteroinferior columns and/or allowing supplementary fixation. Depending on the function of the augment, the surgeon can decide on the sequence of introduction of the hemispherical shell, before or after the augment. Augments should always, however, be used with cement to form a unit with the acetabular component. Given their versatility, augments also allow the use of a hemispherical shell in a position that restores the centre of rotation and biomechanics of the hip. Progressive shedding or the appearance of metal debris is a particular finding with augments and, with other radiological signs of failure, should be recognized on serial radiographs. Mid- to long-term outcomes in studies reporting the use of augments with hemispherical shells in revision total hip arthroplasty have shown rates of survival of > 90%. However, a higher risk of failure has been reported when augments have been used for patients with chronic pelvic discontinuity.

Cite this article: Bone Joint J 2024;106-B(4):312–318.

Abstract

Abstract

Sound management decisions are critical to outcomes in revision arthroplasty. Aiming to improve outcomes, revision networks facilitate speciality trained, high volume surgeons, share experience and best practice, contributing to decision making within and away from their base hospital. We have reported the early clinical experience of East Midlands Specialist Orthopaedic Network (EMSON). In this paper we report beneficial clinical effects, both demonstrable and unquantifiable supporting the process.

Using the UK HES database of revisions, performed before and after EMSON was established, (April 2011 – March 2018), data from EMSON hospitals were compared to all other hospitals in the same time-period. Primary outcome was re-revision surgery within 1 year. Secondary outcomes were re-revision, complications within first two years and median LOS.

57,621 RTHA and 33,828 RTKA procedures were involved with around 1,485 (2.6%) and 1,028 (3.0%) respectively performed within EMSON. Re-revision THA rates, within 1 year, in EMSON were 7.3% and 6.0% with re-revision knee rates 11.6% and 7.4%, pre- and post-intervention. Re-revision rates in the rest England in the same periods were 7.4% to 6.8% for hips and 11.7% to 9.7% for knees. This constituted a significant improvement in 1-year re-revision rates for EMSON knees. (β = −0.072 (−0.133 to −0.01), p = 0.024). The reduction in hip re-revision did not reach statistical significance. Secondary outcomes showed a significant improvement for 1 and 2-year RTHA complication rates.

Re-revision rates for RTKA and complication rates for RTHA improved significantly after the introduction of EMSON. Other outcomes studied also improved to a greater extent in the network hospitals. While anecdotal experience with networks is positive, the challenge in collating data to prove clinic benefit should not be underestimated. Beyond the formal process, additional communication, interaction, and support has immeasurable benefit in both elective and emergency scenarios.

The aim of this study is to examine the differences in long-term mortality rates between infected and aseptic revision total hip arthroplasty (rTHA) in a single specialist centre over an 18-year period.

Retrospective consecutive study of all patients who underwent rTHA at our tertiary centre between 2003 and 2020 was carried out. Revisions were classified as infected or aseptic. We identified patients’ age, gender, American Society of Anaesthesiologists grade (ASA) and body mass index (BMI). The primary outcome measure was all-cause mortality at 5 years, 10 years and over the whole study period at 18 years. Death was identified through both local hospital electronic databases and linked data for the National Joint Registry. Kaplan-Meier survival curves were used to estimate time to death. Where two-stage revision techniques were used of the management of infected cases, these were grouped as a single revision episode for the purpose of analysis.

In total, 1138 consecutive hip revisions were performed on 1063 patients (56 bilateral revisions – aseptic, 10 Excision arthroplasties – infection, 9 – Debridement, Antibiotics, Implant retention (DAIR) with 893 aseptic revisions in 837 patients (78.7%) and 245 infected revisions in 226 patients (21.3%). Average age of the entire study cohort was 71.0 (24–101) with 527 female (49.6%). Average age of the infection and aseptic cohorts was 68.8 and 71.5 respectively. Revisions for infection had higher mortality rates throughout the three time points of analysis. Patients’ survivorship for infected vs aseptic revisions was; 77.8% vs 87.7% at 5 years, 62.8% vs 76.5% at 10 years and 62.4% vs 72.0% at 18 years. The unadjusted 10-year risk ratio of death after infected revision was 1.58 (95% confidence interval 1.28–1.95) compared to aseptic revisions.

rTHA performed for infection is associated with significantly higher long-term mortality at all time points compared to aseptic revision surgery.

The clinical success of THA is accepted, however wide variation in implant usage and outcomes is reported across the world. The Getting It Right First Time initiative in the UK has recommended increased use of cemented constructs in patients over 70. A clear clinical directive has been proposed aiming to reduce revision rates, improve outcomes and increase cost effectiveness.

This study compares the outcomes of cemented, hybrid and cementless THA from a high-volume single center at long-term follow-up.

A prospective database identified 1,699 cemented, 5,782 hybrid and 2,631 cementless THAs. Mean follow-up was 8.1 years, 5.3 years and 6.3 years respectively. Primary endpoint was revision for any reason.

47 (1.79%) cemented, 93 (1.60%) hybrid and 39 (1.48%) cementless THAs underwent revision. The difference in overall revision rate was statistically significant (P=0.002). Mean time to revision was 4.5 years in the cemented group, 2.1 years in the hybrid group and 2.6 years in the cementless group.

1 year survivorship was 99.2% in the cemented group, 99.0% in the hybrid group and 98.9% in the cementless group. 3 year survivorship was 98.6% in the cemented group, 98.8% in the hybrid group and 98.9% in the cementless group. At 10 years it was 97.0%, 97.6% and 97.9% respectively. (Difference not statistically significant (p=0.09). Of relevance cemented fixation showed the lowest 10-year survivorship in patients over 70, over 75 and over 80. (not statistically significant P=0.5, 0.6 and 0.47 respectively).

In a high-volume center, excellent outcomes were achieved at 10 years with all three constructs. Cemented THA had the lowest survivorship compared to hybrid, then cementless fixation. Cemented fixation did not outperform cementless fixation in any age group. Surgeons should monitor their outcomes. Use of a philosophy that works best in their own hands should be supported.

In this review, we discuss the evidence for patients returning to sport after hip arthroplasty. This includes the choices regarding level of sporting activity and revision or complications, the type of implant, fixation and techniques of implantation, and how these choices relate to health economics. It is apparent that despite its success over six decades, hip arthroplasty has now evolved to accommodate and support ever-increasing patient demands and may therefore face new challenges.

Cite this article: Bone Joint J 2020;102-B(6):661–663.

Hip and knee revisions continue to increase in number and complexity. With an understanding that revisions have a high re-revision rate, the importance of correct decisions made at the index procedure, is paramount for patients and surrounding health care economy.

Since January 2015, East Midlands Specialist Orthopaedic Network, (set up on a ‘hub-and-spoke’ model), has allowed all revisions performed within our region, (5 hospitals with a 4 million population), to be discussed at a weekly ‘web’ conference. Integrated radiology allows clinical information to be reviewed remotely at each hospital. Chaired by specialist revision surgeons, with other surgeons, a microbiologist and radiology, vascular, plastics opinions available as required, a formal management plan is ‘signed off’ by the chair and returned to referring institution. We present prospective data of Network activities.

To January 2018, 1007 cases have been referred by 18 consultants from 5 hospitals. A change in proposed plan was seen in 48% cases. (40% involved technique and exposure advice; 18% involved surgical inventory; 22% further investigation; 11% microbiological input; 9% other miscellaneous advice) Few (5%) patients were transferred directly. We also identified 20% increase in outpatient referrals to the ‘hub’.

The network is an excellent tool for discussing complex cases, supporting surgeons in smaller units. A significant number of alterations in plan are made with a few patients transferred directly. We feel the network can only enhance care and are working now to identify exactly how it has affected clinical outcomes. We encourage others to adopt this approach.

Introduction

Between 2005 and 2010, the number of revision hip arthroplasties rose by 49.1%, and revision knee arthroplasties by 92.1%. This number is predicted to rise by 31% and 332% respectively by 2030.

In March 2014, NHS England invited bids to run a pilot revision network. Nottingham Elective Orthopaedic Service (NEOS) was successful and the East Midlands Specialist Orthopaedic Network (EMSON) runs on a ‘hub-and-spoke’ model.

This review examines the future of total hip arthroplasty, aiming to avoid past mistakes

Infected periprosthetic fractures around total hip arthroplasties are increasingly common and extremely challenging problem. The purpose of the study was to review the experience of two tertiary referral units managing infected periprosthetic femoral fractures using interlocking long-stem femoral prostheses either as temporary functional spacers or as definitive implants.

We have identified 69 patients with Vancouver B1 periprosthetic fractures around stable femoral implants. Open reduction internal fixation is the recommended treatment; however recent studies have revealed high rates of nonunion. We have reviewed the fixation techniques utilized to treat these patients, and identified outcomes in relation to rates of union, further surgery and mortality.

Patients were identified from a prospective database of all trauma admissions at Nottingham University Hospitals from 1999 to 2010. Hospital notes were independently reviewed and data retrieved.

69 patients were identified. Mean age 77 years and 63% were female. 51 (74%) occurred around total hip replacements and 18 (26%) around hip hemiarthroplasty after a previous hip fracture.

Periprosthetic fracture occurred around an Exeter stem (n=18), Charnley (n=10), Austin Moore (n=15), other (n=6). 20 patients had undergone previous revision surgery. The mean time from index surgery to fracture was 58 months (median 24) around primary stems, and 48 months (median 22) around revision stems.

6 patients (9%) were treated non-operatively. Five of these had undisplaced fractures (all healed but one required revision due to loosening) and one was too unwell.

63 patients (91%) were treated by open reduction internal fixation. Of these, single plate fixation was performed in 40 cases (64%). In the vast majority of cases, lag screw fixation of the fracture with a long (>12 hole) pre-contoured 4.5mm locking plate was utilised with cables. Both locking and cortical screws were used to achieve stable fixation (Figure 1). A double plate technique was used in 16 cases (25%), where plates were placed perpendicularly to each other (laterally and anteriorly). Strut grafts were used in 13 cases (21%). 7 patients (11%) were treated with cables alone.

23 patients have subsequently died (33%). Two have been lost to follow up and three are awaiting union. There is a mean follow-up of 35 months.

Deep infection occurred in 4 cases (6%). Non-union occurred in four cases (6%). Two of these were infected and one was treated with cables alone. Malunion occurred in one case treated with cables. One patient had a dislocation and two superficial infections occurred.

Further surgery took place in 8 patients (12%). Three of the infected cases were revised and one underwent wound washout. The two other non-unions were revised. Three further revisions were performed: one for malunion, one for aseptic loosening (treated non-operatively) and another for a second periprosthetic fracture. Superficial wound washout was performed in one case.

Mortality was 10% at 3 months, 22% at 1 year and 47% at 3 years.

We have identified that union can be achieved in the majority of cases after periprosthetic fracture fixation. Cable fixation was associated with a high complication rate (7 cases: two requiring revision surgery: one nonunion, one malunion).

We recommend that Vancouver B1 periprosthetic fractures are treated with meticulous technique to achieve anatomical reduction and fracture compression using lag screw technique and plating. Further mechanical support can be provided through the use of a second plate, cables and/or strut grafts.

The clinical results of the cemented Exeter stem in primary hip surgery have been excellent. The Exeter ‘philosophy’ has also been extended into the treatment of displaced intracapsular hip fractures with ‘cemented bipolars’ and the Exeter Trauma Stem (Howmedica).

We have identified an increase in the number of periprosthetic fractures that we see around the Exeter stem. We have also identified a particular group of patients with comminuted fractures around ‘well fixed’ Exeter stems after primary hip surgery that present a particular difficult clinical problem.

Prior to fracture, the stems are not loose, the cement mantle remains sound and bone quality surrounding the reconstruction is good, i.e. classifying it as a Vancouver B1. However the comminuted nature of the fracture makes reduction and fixation with traditional methods difficult. Therefore in these particular circumstances it is often better to manage these as B2 or even B3 fractures, with distal bypass and uncemented reconstruction.

Over an eleven-year period since 1999, 185 patients have been admitted to Nottingham University Hospitals with a periprosthetic femoral fracture around a hip replacement. These patients were identified from a prospective database of all trauma patients admitted to the institution. Of these patients we have identified a cohort of 21 patients (11%) with a periprosthetic fracture around an Exeter polished stem. Hospital notes were independently reviewed and data retrieved. Outcome data was collected with end points of fracture union, re-revision surgery and death. Data was also collected on immediate and long term post-operative complications.

The mean age was 76 years at time of fracture, and 52% were male. The mean duration between primary index surgery and fracture was 18 months (median 11 months).

15 patients were classified as Vancouver B1, and six as B2 fractures. Of the B1 fractures, 14 underwent fixation and one was treated non-operatively. Of the B2 fractures, four were revised, one was revised and fixed using a plate, and one was fixed using a double-plating technique. Prior to fracture, none of the implants were deemed loose although one patient was under review of a stress fracture which subsequently displaced.

One patient died prior to fracture union. All the other patients subsequently went onto unite at a mean of 4 months. There were no deep infections, non- or malunions. No patient underwent further surgery. Dislocation occurred in one patient and a superficial wound infection occurred in one patient which responded to antibiotic treatment. Three other patients have subsequently died at seven, twelve and fifty-three months post fracture due to unrelated causes.

In our series of patients, in addition to the more standard fracture patterns, we have identified a very much more comminuted fracture. Indeed, we have described the appearance as if the tapered stem behaves like an axe, splitting the proximal femur as a consequence of a direct axial load. As a consequence of the injury, the cement mantle itself is severely disrupted. There is significant comminution and soft tissue stripping, calling into question the viability of the residual fragments. Treatment of this type of fracture using a combination of plates, screws and cables is unlikely to provide a sufficiently sound reconstruction. In our experience we believe these fractures around previously ‘well fixed’ Exeter stems should be treated as B2/B3 injuries.