Modified Extended Trochanteric Osteotomy for the Treatment of Vancouver B2/B3 Periprosthetic Fractures of the Femur

Efficacy and safety of modular versus monoblock stems in revision total hip arthroplasty: a systematic review and meta-analysis

BACKGROUND

Both modular and monoblock tapered fluted titanium (TFT) stems are increasingly being used for revision total hip arthroplasty (rTHA). However, the differences between the two designs in clinical outcomes and complications are not yet clear. Here, we intend to compare the efficacy and safety of modular versus monoblock TFT stems in rTHA.

METHODS

PubMed, Embase, Web of Science, and Cochrane Library databases were searched to include studies comparing modular and monoblock implants in rTHA. Data on the survivorship of stems, postoperative hip function, and complications were extracted following inclusion criteria. Inverse variance and Mantel-Haenszel methods in Review Manager (version 5.3 from Cochrane Collaboration) were used to evaluate differences between the two groups.

RESULTS

Ten studies with a total of 2188 hips (1430 modular and 758 monoblock stems) were finally included. The main reason for the revision was aseptic loosening. Paprosky type III was the most common type in both groups. Both stems showed similar re-revision rates (modular vs monoblock: 10.3% vs 9.5%, P = 0.80) and Harris Hip Scores (WMD = 0.43, P = 0.46) for hip function. The intraoperative fracture rate was 11.6% and 5.0% (P = 0.0004) for modular and monoblock stems, respectively. The rate of subsidence > 10 mm was significantly higher in the monoblock group (4.5% vs 1.0%, P = 0.003). The application of extended trochanteric osteotomy was more popular in monoblock stems (22.7% vs 17.5%, P = 0.003). The incidence of postoperative complications such as periprosthetic femoral fracture and dislocation was similar between both stems.

CONCLUSIONS

No significant difference was found between modular and monoblock tapered stems as regards postoperative hip function, re-revision rates, and complications. Severe subsidence was more frequent in monoblock stems while modular ones were at higher risk of intraoperative fracture.

LEVEL OF EVIDENCE

Level III, systematic review of randomized control and non-randomized studies.

TRIAL REGISTRATION

We registered our study in the international prospective register of systematic reviews (PROSPERO) (CRD42020213642).

Comparison of Functional and Radiographic Outcomes Between Two Fixation Methods for Extended Trochanteric Osteotomy in Revision Total Hip Arthroplasty: A Retrospective Cohort Study

BACKGROUND

To compare the functional and radiographic outcomes between two fixation methods for extended trochanteric osteotomy (ETO) in revision total hip arthroplasty (rTHA).

METHODS

Included in this study were 64 patients who underwent ETO in rTHA using either claw-plate fixation (claw-plate group, n = 31) or cable-alone fixation (cable group, n = 33) in our hospital from 2008 to 2020. The functional and radiographic results and complications were compared between the groups during a mean follow-up period of 64 and 78 months.

RESULTS

The Harris hip score and visual analogue scale at the last follow-up improved significantly in both groups, showing no significant statistical difference between the two fixation methods. In the cable group, the mean abductor lever arm, the proximal migration, and medial migration in the affected hip were significantly decreased compared to those in the contralateral normal hip (P < .05), whereas in the claw-plate group no significant statistical differences were observed between two sides. No or slight limping occurred in 25 patients (81%) in the claw-plate group and 16 patients (48%) in the cable group (P = .007). A multiple logistic regression demonstrated that claw-plate fixation could reduce the incidence of postoperative moderate-to-severe limping.

CONCLUSION

Both claw-plate fixation and cable-alone fixation could improve the functional performance of rTHA with ETO, whereas claw-plate fixation could offer superior biomechanical results and gait improvement as compared with cable-alone fixation.

Aseptic Revision of Total Hip Arthroplasty With a Single Modular Femoral Stem and a Modified Extended Trochanteric Osteotomy-Treatment Assessment With the Forgotten Joint Score-12

Background

Aseptic loosening is among the most common reasons for revision total hip arthroplasty (RTHA). Modular revision stems implanted through an extended trochanteric osteotomy (ETO) promise good results, but patient-reported outcome measures (PROMs) are rarely conveyed. This study used the Forgotten Joint Score-12 (FJS-12) to assess patient-reported outcome in patients who had undergone RTHA for aseptic stem loosening using a modified ETO approach with a tapered, fluted modular stem.

Material and methods

A single-center analysis of aseptic RTHA was performed (2007–2019). Clinical results (range of motion, walking ability, function), radiographic results (ETO healing, stem subsidence), and PROMs (FJS-12, Harris Hip Score, European Quality of Life 5D Score) were assessed. Minimum follow-up duration was 1 year. Complications including revisions were recorded.

Results

Primary outcome parameters were assessed on 72 patients (mean age 73.3 years, mean body mass index 27.6kg/m²). Additional PROMs were collected by phone interviews from 41 patients (mean follow-up 5.7 years). In 76%, leg length was restored, and a normal gait was achieved. After 1 year, the ETO was healed in 93%; subsidence occurred in 8.3% of cases. The mean FJS-12 at the final follow-up was 85.6 ± 23.6, and the respective Harris Hip Score and European Quality of Life 5D Score averaged 87 ± 17.8 and 72.9 ± 15.9. Complication and revision rates were 33.3% and 13.9%, respectively.

Conclusion

Aseptic RTHA as presented here resulted in excellent PROMs in the medium term. FJS-12 score averaged 85.6 with a mean follow-up of 5.7 years. Treatment using a modular implant and a modified ETO was associated with good clinical and radiographic outcomes. Complication and revision rates were 33.3% and 13.9%, respectively.

The race for the classification of proximal periprosthetic femoral fractures : Vancouver vs Unified Classification System (UCS) - a systematic review

Background

Periprosthetic femoral fractures (PFFs) represent a major cause for surgical revision after hip arthroplasty with detrimental consequences for patients. The Vancouver classification has been traditionally used since its introduction in 1995. The Unified Classification System (UCS) was described in 2014, to widen the spectrum by aiming for a more comprehensive approach. The UCS also aimed to replace the Vancouver classification by expanding the idea of the Vancouver classification to the whole musculoskeletal apparatus. After introduction of the UCS, the question was raised, whether the UCS found its place in the field of analysing PFFs. Therefore, this systematic review was performed to investigate, the use of the UCS compared to the established Vancouver classification.

Methods

Medline was searched for reports published between 1 January 2016 and 31 November 2020, without language restriction. Included were original articles, irrespective of the level of evidence and case reports reporting on a PFF and using either the Vancouver or the UCS to classify the fractures. Excluded were reviews and systematic reviews.

Results

One hundred forty-six studies were included in the analysis. UCS has not been used in a single registry study, giving a pooled cohort size of 3299 patients, compared to 59,178 patients in studies using the Vancouver classification. Since 2016, one study using UCS was published in a top journal, compared to 37 studies using the Vancouver classification (p=0.29). During the study period, the number of yearly publications remained stagnant (p=0.899).

Conclusions

Despite valuable improvement and expansion of the latter UCS, to date, the Vancouver system clearly leads the field of classifying PFFs in the sense of the common use.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05240-w.

Mid-term outcomes following transfemoral revision of total hip arthroplasty for Vancouver B2/B3 periprosthetic fractures

INTRODUCTION

Periprosthetic femoral fractures (PFF) are often the reason for revising total hip arthroplasty (RTHA). Converting these fractures into modified extended trochanteric osteotomy (mETO) facilitates stem revision. Modular revision stems are a common choice with good results. We present mid-term outcomes in patients undergoing RTHA for Vancouver B2/B3 PFF using a tapered, fluted modular stem with an mETO approach.

MATERIALS AND METHODS

A single-center analysis of patients with RTHA for Vancouver B2/B3 PFF using a single modular implant with mETO was performed (2007 - 2019). Clinical outcome (mobility, range of motion, function), radiological outcome (fracture healing, stem subsidence) and patient reported outcome measures (FJS-12, HHS, EQ-5D) were assessed.

RESULTS

Ninety-seven patients (mean age 78.1 years, BMI 25.8 kg/m², 85.6% B2-fractures) were included; 80 patients had complete clinical and radiological follow-ups. Normal unaided gait without limping was achieved in 38/80 patients. After one year fracture / mETO healing occurred in 74/80 patients; 5.3 years after surgery, the respective FJS-12, HHS and EQ-5D (available in 34 patients) averaged 81.3 ± 30.2, 71.4 ± 18.7 and 0.8 ± 0.2. We documented 7 in-hospital deaths, 18.8% postoperative complications and 13.8% revisions with stem revisions being most commonly for subsequent PFF or subsidence.

CONCLUSION

Good clinical and radiological outcomes and rather low complication and revision rates (18.8% and 13.8%) were achieved. FJS-12 showed excellent results in patients undergoing RTHA for Vancouver B2/B3 PFF using a cementless, dual modular titanium revision stem and an mETO approach. Joint awareness was thereby similar to previously reported primary THA results at 5.3 years follow-up.

The different failure modes of the connecting elements of the modular hip arthroplasty revision stem Revitan

INTRODUCTION

Fracture of the femoral stem is the cause of ~1 % of revisions after total hip arthroplasty. The risk increases intrinsically with modularity, whereby modularity is particularly useful in revision arthroplasty. We present 7 cases of failure of a specific modular, tapered, fluted, titanium alloy Revitan stem and analyse the different failure modes.

METHODS

Retrospective review of all Revitan stems revised at our institutions due to implant failure and analysis of clinical presentation, diagnostic workup, and failure mode. The retrieved components were analyzed by optical and scanning electron microscopy.

RESULTS

A total of 7 cases were included. There was a significant time lag between symptom onset and correct diagnosis. Conventional radiographs and low-dose CT scans (CT scout imaging) were decisive for diagnosis. All failures occurred at the level of the connection between the proximal component and the distal part of the stem. Three different failure modes were identified: loosening of the proximal component, fatigue fracture of the connection pin, and distal loosening of the connection pin. No alterations of the microstructure or deviation from manufacturing specifications regarding dimensions were observed. Failure was caused by mechanical overload.

CONCLUSION

Conventional radiographs are the mainstay in identifying failed modular stems. Repeated radiographs and low-dose CT scans may be helpful additions. No single modification of the connection will address all possible failure modes. Modularity of revision stems offers advantages up until insertion of the definitive stem. Monoblock definitive stems might overcome the potential mechanical weaknesses of modularity and should be considered in relatively young, heavy and active patients.

Short proximal components in modular revision stems carry a higher risk for stem fractures

INTRODUCTION

Fractures of modular hip revision stems are not uncommon. The current study examined implant-related factors on stem fracture. We hypothesised that in a modular stem the fracture risk is increased with the use of a short proximal implant component.

MATERIALS AND METHODS

Anonymised data of all 32 patients in Switzerland with a Revitan modular hip system who had a stem fracture were obtained from the manufacturer. Implant and patient data were compared with all components implanted in Switzerland during the same time interval.

RESULTS

Between 2002 and 2017, 4834 Revitan stems were implanted, of which 32 fractured. A smaller size of the proximal stem component was significantly associated with a higher fracture risk (p < 0.001). Compared with the control group, the proportion of male patients was higher among the fracture cases, patients were younger, and they had a higher body weight (p < 0.001, respectively).

CONCLUSIONS

The present study suggests that small proximal stem components increase the load at the modular junction due to size and lack of bony support. Surgeons should therefore avoid short proximal components so that the mid-stem junction lies as distally as possible and the risk of fracture is minimised.

Extended trochanteric osteotomy (ETO) and fluted tapered modular stems in revision hip arthroplasty. Does ETO integrity or consolidation, really matter?

Introduction

The objective of this study was to assess if the fracture and/or non-union of extended trochanteric osteotomy (ETO) affected the behavior and survival of modular fluted and tapered distal fixation stems in revision total hip arthroplasties (rTHA).

Methods

We retrospectively analyzed 52 rTHA in 52 patients. Preoperative diagnoses were mechanical loosening (42 cases), septic loosening (8), periprosthetic fracture (1), and femoral stem fracture (1). According to the Paprosky classification, femoral bone stock deficiencies were 19 type-II, 26 type IIIA, and 7 type IIIB. We assessed the behavior of the osteotomy (union, fracture, migration) and the survival and behavior (integration and subsidence) of prosthetic femoral stems.

Results

ETO union and non-union rates were 84.61% (44 patients) and 15.38% (8 cases) respectively. There were twelve (23%) intra-operative fractures of the osteotomy fragment and 11 (21.15%) migrations (4.5 mm on average). We observed bone union in 39 (75%) stems and 13 (25%) stable fibrous unions. Nine (17.3%) stems subsided 7 mm (2-15 mm) on average before becoming stable. Stem subsidence and integration was not significantly affected by ETO fracture/no fracture or union/non-union. The postoperative Harris Hip Score (HHS) improved significantly as compared to the pre-operative HHS (38.41 ± 3.54 vs 85.29 ± 3.36; p < 0.01). Patients were followed up for 55 (24-100) months. The overall implant survival at the end of follow-up was 100%.

Conclusions

In this series, neither the non-union nor the intra-operative fracture of the ETO segment affected the behavior or medium-term survival of femoral stems.

Outcomes and Risk Factors of Extended Trochanteric Osteotomy in Aseptic Revision Total Hip Arthroplasty: A Systematic Review

BACKGROUND

Although extended trochanteric osteotomy (ETO) is an effective technique for femoral stem removal and for the concomitant management of proximal femoral deformities, complications including persistent pain, trochanteric nonunion, and painful hardware can occur.

METHODS

The US National Library of Medicine (PubMed/MEDLINE) and the Cochrane Database of Systematic Reviews were queried for publications utilizing the following keywords: "extended" AND "trochanteric" AND "osteotomy."

RESULTS

Nineteen articles were included in the present study with 1478 ETOs. The mean overall union rate of the ETO was 93.1% (1377 of 1478 cases), while the overall rate of radiographic femoral stem subsidence >5 mm was 7.1% (25 of 350 cases). ETO union rates and femoral stem subsidence rates were similar between patients with periprosthetic fractures treated with total hip arthroplasty (THA) revision and ETO and patients treated with THA revision and ETO for reasons other than fractures. There was limited evidence that prior femoral cementation and older age might negatively influence ETO union rates.

CONCLUSION

There was moderate quality evidence to show that the use of ETO in aseptic patients undergoing single-stage revision THA is safe and effective, with a 7% rate of ETO nonunion and subsidence >5 mm in 7%. ETO can be safely used in cases with periprosthetic fractures in which stem fixation is jeopardized and a reimplantation is required. A well-conducted ETO should be preferred in selective THA revision cases to prevent intraoperative femoral fractures which are associated with deteriorated clinical outcomes. The use of trochanteric plate with cables should be considered as the first choice for ETO fixation.

Extension of the Direct Anterior Approach for the Treatment of Periprosthetic Femoral Fractures

BACKGROUND

Periprosthetic femoral fractures (PFFs) after total hip arthroplasty are devastating complications often resulting in functional limitations and increased mortality. The use of the direct anterior approach (DAA) is becoming more popular, and the number of revisions done through this interval is increasing. The DAA interval can be expanded to treat PFFs. This retrospective case series assessed outcomes of PFF patients treated with the extension of the DAA interval.

METHODS

The study contained 40 patients (40 hips). Mean patient age was 74.3 years (range, 55.1-92.2 years). Mean follow-up time was 50.4 months (range, 20-98.2 months). Fractures were classified as Vancouver B2 (n = 36) and B3 (n = 4).

RESULTS

Median cut-to-close time was 152 minutes (interquartile range: 80-279). There were five complications (12.5%): 2 deaths, 1 transient femoral nerve palsy, 1 fissure distal to the stem, and 1 hematoma.

CONCLUSION

Expansion of the DAA interval to treat PFF showed similar results compared with other surgical approaches in terms of mortality, complications, fracture healing, and dislocation rate. These results indicate that femoral revision for PFF in the DAA interval is a safe and reliable procedure compared with other surgical approaches for the treatment of Vancouver B2 and B3 periprosthetic fractures.

What can the surgeon do to reduce the risk of junction breakage in modular revision stems?

Modular revision stems are very common in hip arthroplasty, but junction fracture remains a known failure mechanism. A review of the literature with description of cases with junction breakage of modular revision stems showed that in all 24 analyzed cases, there was a common finding: the combination of an effective osteointegration of the distal component and missing medial bone support of the proximal component. The result was a bending stress point of the stem construction in the region of the junction. A technique using the combination of short distal component and longer proximal components may alter this stress pattern, allow proximal implant support, and reduce the risk of junction fracture. Moreover, filling of gaps between the modular component and the medial region of the femoral calcar in endofemoral implantation, a double osteotomy in significant bowed femurs, and treating medial bone defects with structural allografts additionally can reduce the risk of junction breakage.

Current Uses of the Transtrochanteric Approach to the Hip: A Systematic Review

BACKGROUND

The indications and technique for the transtrochanteric approach to the hip have evolved greatly since its initial popularization in the 1960s. The purpose of this systematic review was to assess current uses of this approach on the basis of indications, osteotomy technique, trochanteric fixation method, complications, and functional outcome.

METHODS

A comprehensive search of MEDLINE and Embase databases from January 2000 to July 2017 was performed in accordance with the PRISMA guidelines. Articles were divided into 3 major categories on the basis of the type of hip surgery performed: (1) primary arthroplasty, (2) revision arthroplasty, and (3) joint-preserving procedures. Patient data were then analyzed according to these 3 categories.

RESULTS

Seventy-six studies (5,028 hips), mainly of Level-IV evidence, were included. Four types of osteotomy were reported for a variety of indications. Rates of nonunion were 6.0% (303 of 5,028) across all studies, 4.2% (39 of 921) for primary arthroplasty, 6.7% (114 of 1,690) for revision arthroplasty, and 4.4% (56 of 1,278) for joint-preserving procedures. Rates of dislocation were 1.5% (14 of 921) for primary arthroplasty and 4.6% (77 of 1,690) for revision arthroplasty. The rate of osteonecrosis after joint-preserving procedures was 1.1% (14 of 1,278). Rates of deep infection were 1.1% (55 of 5,028) across all studies, 0.1% (1 of 921) for primary arthroplasty, 2.1% (36 of 1,690) for revision arthroplasty, and 0.6% (8 of 1,278) for joint-preserving procedures.

CONCLUSIONS

The transtrochanteric approach remains useful in cases requiring extensile exposure of the acetabulum or femoral medullary canal. However, trochanteric complications continue to pose a clinical challenge.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Femoral Bone Restoration Patterns in Revision Total Hip Arthroplasty Using Distally Fixed Modular Tapered Titanium Stems and an Extended Trochanteric Osteotomy Approach

BACKGROUND

Mechanical failure of modular revision stems is a serious complication in revision total hip arthroplasty. The lack of adequate osseous support to the proximal component, especially in cases of an extended trochanteric osteotomy approach, is considered a risk factor for stem failure. In this study, we analyze proximal bone regeneration patterns in patients undergoing revision total hip arthroplasty for aseptic stem loosening through an extended trochanteric osteotomy approach using an uncemented dual modular stem.

METHODS

Fifty-four patients treated for aseptic stem loosening were radiologically reviewed. The femur was divided according to the Gruen zones. Preoperative bone loss, formation of new cancellous bone, and presence of direct osseous contact to the stem were noted right away for each Gruen zone. The presence of osseous support at the modular junction and the proximal component were examined.

RESULTS

All patients showed restoration of proximal bone mass at final follow up. New bone formation was first seen in more distally located Gruen zones. Cases with longer proximal components had a trend toward earlier osseous support at the modular junction. Overall, 75% of patients showed osseous support at the modular junction 2 years after surgery.

CONCLUSION

Restoration of proximal bone occurs in a distal to proximal direction. Shorter proximal components require more time until osseous support to the modular junction is achieved, which may result in a higher risk of mechanical failure. Based on this study, bony support at the modular junction should not be expected in 25% of cases 2 years after surgery.