Extended trochanteric osteotomy: improving the access and reducing the risk in revision THA

Removal of uncemented components: hope for the best, prepare for the worst-technical tips and tricks

Removing well-fixed uncemented components can be challenging. With thoughtful surgical planning, appropriate surgical instruments, and proper surgical techniques, most implants can be removed expeditiously with little bone loss and minimal impact on the subsequent reconstruction. Preoperative planning is one of the most essential steps to remove uncemented implants. Obtaining previous surgical records, although tedious, should always be attempted preoperatively to determine if specific instruments will be required and to help anticipate which steps may need special attention. These include the presence of ceramic or metal bearings and the presence of acetabular screws or stem collars. Without proper preparation and available tools, the removal of implants can negatively impact the subsequent reconstruction and patient outcomes. We will describe techniques and practical tips for removing uncemented stems from the top (intramedullary) or transfemoral using an extended trochanteric osteotomy. We will also describe techniques and tools to remove uncemented acetabular shells efficiently. Case examples will highlight these clinical situations where careful planning is necessary and potential problems that may be encountered with the recurring theme of preparing for the worst but hoping for the best. We have also included cases such as removing well-fixed cementless collared stems, broken stems, and fully coated stems.

The feasibility of a novel 3D-Printed patient specific cutting guide for extended trochanteric osteotomies

BACKGROUND

The extended trochanteric osteotomy (ETO) is a surgical technique utilized to expose the intramedullary canal of the proximal femur, protect the soft tissues and promote reliable healing. However, imprecise execution of the osteotomy can lead to fracture, soft tissue injury, non-union, and unnecessary morbidity. We developed a technique to create patient specific, 3D-printed cutting guides to aid in accurate positioning of the ETO and improve osteotomy quality and outcomes.

METHODS

Patient specific cutting guides were created based on CT scans using Synopysis Simpleware ScanIP and Solidworks. Custom 3D printed cutting guides were tested on synthetic femurs with foam cortical shells and on cadaveric femurs. To confirm accuracy of the osteotomies, dimensions of the performed osteotomies were compared to the virtually planned osteotomies.

RESULTS

Use of the patient specific ETO cutting guides resulted in successful osteotomies, exposing the femoral canal and the femoral stem both in synthetic sawbone and cadaveric testing. In cadaveric testing, the guides allowed for osteotomies without fracture and cuts made using the guide were accurate within 6 percent error from the virtually planned osteotomy.

CONCLUSION

The 3D-printed patient specific cutting guides used to aid in ETOs proved to be accurate. Through the iterative development of cutting guides, we found that a simple design was key to a reliable and accurate guide. While future clinical trials in human subjects are needed, we believe our custom 3D printed cutting guide design to be effective at aiding in performing ETOs for revision total hip arthroplasty surgeries.

[Tips and tricks of cement removal in the case of revision surgery]

BACKGROUND

In Germany, current revision rates after arthroplasty range between 28-37%. In particular, remaining cement residues are causative for additional revision surgery after periprosthetic joint infection, which is why complete cement removal is of high importance. However, the removal of remaining cement residues often confronts the surgeon with technical challenges. Complication-free and complete cement removal requires extensive preoperative preparation in order to develop the best possible surgical strategy.

TREATMENT

Special instrument sets to facilitate cement removal in revision cases are available from various manufacturers. In addition to endoluminal approaches, access enhancements such as extended osteotomies exist to facilitate complete cement removal. Finally, the surgeon should be able to give the indication for an intraoperative procedural change after a defined time interval.

Clinical and radiographic outcomes of long monoblock, hydroxyapatite-coated stem in revision hip arthroplasty with extended trochanteric osteotomy: a multicenter study

BACKGROUND

The distally fixed stem used in revision total hip arthroplasty (rTHA) with extended trochanteric osteotomy (ETO) is subject to periprosthetic fracture, stem subsidence, and stress shielding. The prospective multicentric study aimed to assess the clinical and radiographic outcomes, and complications of using the Corail revision stem in rTHA with ETO.

METHODS

Sixty-four patients undergoing rTHA with ETO using the Corail revision stem between 2019 and 2020 were enrolled in the study. We performed a postoperative follow-up of the patient and obtained radiographs and Harris hip scores (HHSs). These results were used to analyze ETO union, Engh scores, bone remodeling, stem stability and hip function.

RESULTS

The mean follow-up duration was 34 months (range 23-41). Sixty-two patients who underwent ETOs achieved complete healing at the final follow-up. Fifty-nine hips had bony ingrowth from the osteotomy fragment to the stem without radiolucent lines. The postoperative Engh score was 21.3 ± 3.59 (range 15.5-27.0). Forty-three hips had regeneration in the proximal femur. Two patients had transient thigh pain postoperatively. The postoperative HHS improved from 40.7 ± 16.67 (range 0-67) preoperatively to 82.1 ± 6.83 (range 73-93).

CONCLUSION

Corail revision stems are a viable and reliable option in rTHA with ETO. This stem had excellent clinical and radiographic outcomes, resulting in a high rate of ETO union and stem survival. The revision stem enabled restoration of proximal bone stock in femurs with prerevision bone defects, which were prepared for the next revision operation. Level of evidence Level IIb, Prospective self-control study.

Extended trochanteric osteotomy is a safe procedure in two-stage hip revision: a systematic review of the literature

BACKGROUND

Extended trochanteric osteotomy (ETO) has proved to be an effective technique in complicated stem removal in femoral aseptic loosening or periprosthetic fracture. Debate remains about its safety in periprosthetic joint infection (PJI). The primary aim of this study is to analyze the ETO reinfection and union rate in two-stage hip revision.

MATERIAL AND METHODS

A systematic literature review was performed regarding all studies reporting ETO outcomes in the two-stage revision for hip PJI up to October 2022, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria. A literature search was conducted in the following databases: MEDLINE/EMBASE, Scopus, Web of Science, and Cochrane. Quality assessment of the articles was performed using the Methodological Index for Non-Randomized Studies. This systematic review was registered in the International Prospective Registry of Systematic Reviews. Patient demographic, clinical, and surgical data were collected.

RESULTS

This systematic review included and analyzed nine clinical studies with a total of 382 ETO PJI hips in two-stage revision. The overall ETO reinfection rate was 8.9% (34 hips), consistent with the reinfection rate after two-stage revision in patients without ETO. The overall ETO union rate was 94.8% (347 hips), comparable to the ETO union rate in non-septic patients. Compared between a group of patients with ETO PJI and a group of patients with non-PJI ETO, there were no significant differences in postoperative complications, both septic and aseptic, and for postoperative HHS.

CONCLUSION

ETO proved to be a safe and effective procedure in PJI revisions. It may be a viable option in challenging femoral stem removal during the two-stage hip revision in PJI.

LEVEL OF EVIDENCE

IV.

The influence of hip revision stem spline design on the torsional stability in the presence of major proximal bone defects

BACKGROUND

Despite the success of primary total hip arthroplasty, the number of revisions remains high. Infection, aseptic loosening, periprosthetic fractures and dislocations are the leading causes of hip revision. Current revision stem designs feature a tapered body with circumferential placed longitudinal thin metal splines that cut into the femoral cortex of the diaphysis to provide axial and rotational stability. Modifications to the spline design may help improve primary stability in various bone qualities. The purpose of this study was to evaluate whether the rotational stability of a revision hip stem can be improved by an additional set of less prominent, wider splines in addition to the existing set of splines. It is hypothesized that the additional splines will result in greater cortical contact, thereby improving torsional strength.

METHODS AND FINDINGS

The ultimate torsional strength of an established modular revision stem (Reclaim®, DePuy Synthes) was compared to a Prototype stem design with two sets of splines, differing in prominence by 0.25 mm. Five pairs of fresh-frozen human femurs (n = 10) were harvested and an extended trochanteric osteotomy was performed to obtain common bone defects in revision. Stems were implanted using successive droptower impacts to omit variability caused by mallet blows. The applied energy was increased from 2 J in 1 J increments until the planned implantation depth was reached or seating was less than 0.5 mm at 5 J impact. The ultimate torsional strength of the bone-to-implant interface was determined immediately after implantation. Image superposition was used to analyze and quantify the contact situation between bone and implant within the femoral canal. Cortical contact was larger for the Prototype design with the additional set of splines compared to the Reclaim stem (p = 0.046), associated with a higher torsional stability (35.2 ± 6.0 Nm vs. 28.2 ± 3.5 Nm, p = 0.039).

CONCLUSIONS

A second set of splines with reduced prominence could be shown to improve primary stability of a revision stem in the femoral diaphysis in the presence of significant proximal bone loss. The beneficial effect of varying spline size and number has the potential to further improve the longevity of revision hip stems.

Commercially manufactured spacers for the treatment of periprosthetic joint infection of the hip

BACKGROUND

Periprosthetic joint infection remains a common and serious complication after hip arthroplasty. To improve function and patient comfort after joint removal in two-stage revision, commercially manufactured spacers for the hip joint allow retention of the anatomical joint geometry thereby limiting soft tissue contraction and allow mobilization.

INDICATIONS

Periprosthetic joint infection of the hip, septic arthritis with severe destruction of the hip cartilage and/or bone requiring arthroplasty.

CONTRAINDICATIONS

Allergies to polymethylmethacrylate (PMMA) or antibiotics, severe hip dysplasia with insufficient cranial support, incompliant patient, large osseous defect of the acetabulum, insufficient metaphyseal/diaphyseal support of the femoral bone, resistance of the microbiological pathogen to spacer-inert antibiotic medication, inability to perform primary wound closure requiring temporary open-wound therapy.

SURGICAL TECHNIQUE

Preoperative templating on radiograph; removal of joint prosthesis and thorough debridement with removal of all foreign material; trial spacer selection and insertion and trial reduction of the joint, fixing the spacer with PMMA to the proximal femur, final reduction, radiograph and stability test.

RESULTS

Data were analyzed from patients treated between 2016 and 2021. In all, 20 patients were treated with preformed spacers and 16 with custom-made spacers. Pathogens were detected in 23 of the 36 cases (64%). Polymicrobial infections were present in 8 of 36 cases (22%). In patients who received preformed spacers, there were 6 cases of spacer-related complications (30%). Of the 36 patients (83%), 30 were reimplanted with a new implant; 3 patients died due to septic or other complications before reimplantation (8%). Average follow-up was 20.2 months after reimplantation. There were no major differences between the two groups of spacers. Patient comfort was not measured.

Greater trochanteric osteotomy and subtrochanteric osteotomy in primary/revision total hip arthroplasty

Osteotomy of the femur is necessary in some cases of primary/revision total hip arthroplasty (THA) procedure. There are two mainly used femur osteotomy methods in THA: greater trochanteric osteotomy and subtrochanteric osteotomy. Greater trochanteric osteotomy can improve hip exposure, provide greater stability against dislocation and favorably influence the abductor moment arm. Whether in the primary or revision THA, greater trochanteric osteotomy has its unique position. Subtrochanteric osteotomy adjusts the degree of femoral de-rotation and corrects the leg length. It is widely used in hip preservation and arthroplasty surgery. All osteotomy methods have specific indications, while nonunion is the commonest complication. In this paper, we analyze the greater trochanteric osteotomy and the subtrochanteric osteotomy in primary/revision THA and summarize the characteristics of different osteotomy methods.

Impact of Indication for Revision THA on Resource Utilization

BACKGROUND

Demographic variables play an important role in outcomes following revision total hip arthroplasty (rTHA). Surgical and in-patient variables as well as outcomes vary between indications for rTHA. The purpose of this study was to investigate the impact of the indication for the rTHA on costs and postoperative outcomes.

METHODS

This retrospective cohort analysis investigated all patients who underwent unilateral, aseptic rTHA at an academic orthopaedic specialty hospital who had at least 1-year postoperative follow-up. In total, 654 patients were evaluated and categorized based on their indication for aseptic rTHA. Demographics, direct and total procedure costs, surgical factors, postoperative outcomes, and re-revision rates were collected and compared between indications.

RESULTS

Younger patients had the greatest leg length discrepancy (LLD) and older patients had the highest incidence of periprosthetic fracture (PPF) (P = .001). The greatest proportion of full revisions were found for LLD (16.7%) and head/polyethylene liner-only revisions for metallosis/adverse tissue reaction (100%). Operative time was significantly longest for LLD revisions and shortest for metallosis/adverse tissue reaction revisions (P < .001). Length of stay was longest for periprosthetic fracture and shortest for LLD and stiffness/heterotopic ossification (P < .001). Re-revision rate was greatest for implant failure and lowest for LLD. Total cost was highest for PPF (148.9%) and lowest for polyethylene liner wear (87.7%).

CONCLUSIONS

Patients undergoing rTHA for indications such as PPF and aseptic loosening were associated with longer operative times, length of stay and higher total and direct costs. Therefore, they may need increased perioperative attention with respect to resource utilization, risk stratification, surgical planning, and cost-reducing measures.

LEVEL III EVIDENCE

Retrospective Cohort Study.

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.

Extended Trochanteric Osteotomy Closure Performed Before or After Canal Preparation and Stem Impaction Does Not Affect Axial Stability

BACKGROUND

An extended trochanteric osteotomy (ETO) safely addresses femoral component removal during challenging revision total hip arthroplasty. However, no prior study has evaluated whether a difference in axial stability exists between ETO closure performed before (reconstitution) or after (scaffolding) canal preparation and stem impaction. We hypothesized that given the absence of clinical reports of outcome differences despite the wide use of both practices, no significant difference in the initial axial stability would exist between the 2 fixation techniques.

METHODS

ETOs were performed and repaired using the reconstitution technique for the 6 right-sided femora and the scaffolding technique for the six left-sided femora. The 195-mm long, 3.5°-tapered splined titanium monobloc stems were impacted into 6 matched pairs of human fresh cadaveric femora. Three beaded cables were placed in a standardized fashion on each specimen, 1 for prophylaxis against osteotomy propagation during reaming/impaction and 2 to close the ETO. Stepwise axial loading was performed to 2600 N or until failure, which was defined as subsidence >5 mm or femoral/cable fracture.

RESULTS

All specimens successfully resisted axial testing, with no stem in either ETO repair group subsiding >2 mm. The mean subsidence for the reconstitution group was 0.9 ± 0.4 mm, compared to 1.2 ± 0.5 mm for the scaffolding group (P = .2).

CONCLUSION

In this cadaveric model with satisfactory proximal bone stock, no difference existed between the reconstitution and scaffolding ETO repair techniques, and both provide sufficient immediate axial stability in a simulated revision total hip arthroplasty setting under physiologic loads.

Save the Greater Trochanter: A Novel Modification to the Extended Trochanteric Osteotomy

The extended trochanteric osteotomy is the workhorse for removal of well-fixed femoral stems during total hip revision arthroplasty. Despite its reliable performance in exposing the implants for removal and accessing the femoral canal, significant complications can occur. Though these complications are rare, trochanteric nonunion, trochanteric escape, and femoral implant subsidence can have a significant negative impact on gait mechanics and patient outcome. If access to the canal was still possible and the greater trochanter could remain in place, these complications could be minimized or possibly even eliminated. This paper describes a novel technique using a lateral cortical window just distal to the greater trochanter that allows removal of a well-fixed stem and leaves the greater trochanter intact.

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.

Outcomes of Revision Hip Arthroplasty Using the Supine Anterior-Based Muscle Sparing Approach

Background

In the United States, the number of revision total hip arthroplasty (THA) cases is projected to grow from 50,000 in 2014 to 85,000 by 2030. The anterior-based muscle sparing approach (ABMS) has been described as a viable approach for primary THA, but little has been written in the revision setting. This study compares the supine ABMS approach to alternative approaches in revision THA.

Material and methods

A retrospective review was performed on 149 revision THAs from 2016 to 2019. The ABMS, modified Müller Hardinge (MMH), and posterolateral (PL) approaches were studied. Age, reason for arthroplasty, length of operation, length of stay, blood loss, and complications were extracted. Clinical outcomes were measured by the Hip Disability and Osteoarthritis Outcome Score, Modified Harris Hip Score, University of California Los Angeles activity score, and Veterans RAND 12 Mental/Physical scores.

Results

Approaches included 52 ABMS (33.8%), 58 MHH (37.7%), and 39 PL (25.3%). Complexity of cases and patient demographics were equivalent for each cohort. Extensile approaches were used in 12 of the 52 ABMS, 26 of the 58 MMH, and 13 of the 39 PL revisions, including acetabular cages, open reduction internal fixation for periprosthetic fracture, extended trochanteric osteotomy, hardware removal, and/or pelvic discontinuity. There were no differences for blood loss, length of stay, complications, and outcome scores between approaches.

Conclusion

We found no difference in complications or clinical outcome scores between the ABMS, MMH, and PL approaches for revision THA. The supine ABMS approach provides adequate extensile exposure of the femur and acetabulum for complex revisions and is a reliable approach for revision THA.

The Mechanism of Metallosis After Total Hip Arthroplasty

Metallosis is defined as the accumulation and deposition of metallic particles secondary to abnormal wear from prosthetic implants that may be visualized as abnormal macroscopic staining of periprosthetic soft tissues. This phenomenon occurs secondary to the release of metal ions and particles from metal-on-metal hip implants in patients with end-stage osteoarthritis. Ions and particles shed from implants can lead to local inflammation of surrounding tissue and less commonly, very rare systemic manifestations may occur in various organ systems. With the incidence of total hip arthroplasty increasing as well as rates of revisions due to prosthesis failure from previous metal-on-metal implants, metallosis has become an important area of research. Bodily fluids are electrochemically active and react with biomedical implants. Particles, especially cobalt and chromium, are released from implants as they abrade against one another into the surrounding tissues. The body’s normal defense mechanism becomes activated, which can elicit a cascade of events, leading to inflammation of the immediate surrounding tissues and eventually implant failure. In this review, various mechanisms of metallosis are explored. Focus was placed on the atomic and molecular makeup of medical implants, the component/surgical associated factors, cellular responses, wear, tribocorrosion, joint loading, and fluid pressure associated with implantation. Current treatment guidelines for failed implants include revision surgery. An alternative treatment could be chelation therapy, which may drive future studies.

Arthroplasty is an invasive procedure which disrupts surrounding joint tissues, and can greatly perturb the joint’s immune homeostasis. In some instances, this may pose a difficult challenge to implant integration. Particles released from implants into the surrounding joint tissues activate the body’s defense mechanism, eliciting a cascade of events, which leads to biotribocorrosion and electrochemical attacks on the implant. This process may lead to the release of even more particles. Besides, implant makeup and designs, frictions between bearing surfaces, corrosion of non-moving parts with modular junctions, surgical mistakes, patient factor, comorbidities, and loosened components can alter the expected function of implants. High accumulations of these ions and particulates result in metallosis, with accompanying adverse complications. Current recommended treatment for failed prosthesis is revision surgeries. However, chelation therapy as a prophylactic intervention may be useful in future efforts but more investigation is required.

Total Hip Replacements in Patients with Rare Pathologic Conditions Affecting Bone

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As a result of the advances in surgical technique and implant design, total hip arthroplasty (THA) is increasingly offered for the management of osteoarthritis of the hip in patients with fragile or pathologic bone.

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Posttraumatic or congenital deformities associated with fragile or pathologic bone are frequently encountered and necessitate diligent preoperative planning.

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Surgeons should be prepared to evaluate and manage intraoperative iatrogenic fracture.

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While there is limited evidence to date, components made with computer-assisted design can be considered, given the unique and highly variable patient population.

Medium term outcome of Lancaster cortical window technique for extraction of femoral stem in revision hip arthroplasty

Background

The extraction of a femoral stem during the revision hip arthroplasty can be a daunting task and can lead to catastrophic complications for the patient. A sound technique employed intraoperatively helps in the speedy recovery of the patient and reduces the risk of future surgical interventions. In this study, we present a medium-term outcome of our novel Lancaster cortical window technique which can be used for the removal of cemented or uncemented femoral stems.

Methods

The study was conducted at a specialist centre in the north-west of the UK from January 2014 to May 2019. This is a retrospective case series where patients were treated surgically using the Lancaster cortical window technique for removal of the femoral implant during a revision hip arthroplasty. Patient’s electronic notes and radiographs were used to evaluate the functional and radiological outcome.

Results

In this study, 18 patients were managed surgically using the novel Lancaster window technique. The mean age of all the patients was 81.5 years, and the male to female ratio was 10:8. Fifteen patients underwent revision surgery for aseptic loosening of the femoral and acetabular components. The rest of the three patients had revision surgery for a broken femoral stem, intraoperative femoral canal perforation while implanting a total hip replacement femoral stem and infection. Twelve femurs were replanted with uncemented long femoral stems and six with long cemented stems. The cortical window osteotomy united in all the patients in 4.2 months (mean). The mean follow-up of these patients is 20.9 months, and none of them had any implant subsidence or loosening at the time of their last follow-up.

Conclusion

We believe Lancaster cortical window technique can be safely used for the removal of cemented stems during revision hip arthroplasty without the need for expensive equipment.

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.

Trochanteric osteotomy in revision total hip arthroplasty

Trochanteric osteotomy is a technique that allows expanded exposure and access to the femoral canal and acetabulum for a number of indications.There has been renewed interest in variants of this technique, including the trochanteric slide osteotomy (TSO), extended trochanter osteotomy (ETO), and the transfemoral approach, for both septic and aseptic revision total hip arthroplasty (THA).Osteotomy fixation is crucial for achieving union, and wire and cable-plate systems are the most common techniques.TSO involves the creation of a greater trochanter fragment with preserved abductor attachment proximally and vastus lateralis attachment distally.This technique may be particularly useful in the setting of abductor deficiency or when augmented acetabular exposure is needed.ETO is a posterior-laterally based extensile approach that has been successfully utilized for aseptic and septic indications; most series report a greater than 90% rate of union.The transfemoral approach, as known as the Wagner osteotomy, is an extensile femoral approach and is more anterior-based than the alternate posterior-based ETO. It may be particularly useful for anterior-based approaches and anterior femoral remodelling; rates of union after this approach in most reports have been close to 100%. Cite this article: EFORT Open Rev 2020;5:477-485. DOI: 10.1302/2058-5241.5.190063.