Mid- to Long-Term Outcomes of Cementless Modular, Fluted, Tapered Stem for Massive Femoral Bone Loss in Revision Total Hip Arthroplasty

Clinical outcomes and survival rates of a uncemented modular revision stem system in hip arthroplasty: a 10-year single-institution study on a frail population

INTRODUCTION

The increasing prevalence of primary hip arthroplasty has led to a parallel rise in revision cases. Femoral revision often entails compromised bone integrity, requiring consideration of various solutions for optimal reconstructive options. Despite technological advancements, there is limited evidence on the clinical outcomes of the latest modular revision stems. This study aimed to evaluate the clinical outcomes and survival rates of next generation uncemented modular revision stem in patients undergoing hip revision surgery.

MATERIALS AND METHODS

This retrospective single-center study assessed the survival and failure causes of a specific uncemented modular stem in 48 patients undergoing hip revision surgery between 2012 and 2022. Data included preoperative parameters, surgical details, and postoperative outcomes measured through clinical and radiographic assessments. Forty-eight patients (25 males, 23 females; mean age 72 years) were included, with a mean Charlson Comorbidity Index of 5. Preoperative diagnoses varied, with periprosthetic joint infection (PJI) being the most common (45.8%), followed by periprosthetic fractures (27.1%). Partial revisions occurred in 60.4%, total revisions in 39.6%. According to Paprosky classification of femoral bone loss, type II and III were the most represented, respectively 35.4% and 50%.

RESULTS

At a mean follow-up of 4.6 years, stem survival was 92.5%. Complications (20%) included dislocation, PJI, fracture, and loosening; the overall reoperation rate was 12.5%. The SF-12 physical score was 43.6, while the mental score was 51.1. The HOOS score was 71.8, and the HHS score was 71.4. Radiographic analysis identified nonprogressive osteolysis in 15.1% of patients.

CONCLUSIONS

This study on this uncemented modular revision stem demonstrated favorable outcomes in an elder fragile population with moderate to severe femoral bone loss. The implant's modularity provides versatility in addressing various defects, without any implant breakage observed during the study period. Literature comparison highlighted similar outcomes despite sample size differences. The promising results warrant continued investigation into the long-term survivorship of this modular stem system.

Implant breakage and revision factors for modular fluted tapered stems in revision total hip arthroplasty

PURPOSE

Modular stems in revision total hip arthroplasties allow diaphyseal fixation and optimal restoration of the architecture of the proximal femur. Several studies report metaphyseal implant breakage having a negative impact on survivorship. The aim of the study was to evaluate the outcome of an uncemented modular fluted tapered stem (MFT) in revision surgery.

METHODS

In a retrospective study, 316 patients who had revision surgery using the same design of MFT implant (Modular Revision Stem [MRS], Lima Corporate, Italy) between 2012 and 2017 were identified. Patients were male in 51% of cases and mean age was 74 years. Indications were 110 periprosthetic fractures, 98 periprosthetic joint infection, 97 aseptic loosening, 10 instability and 1 other cause. Survivorship, complications, clinical and radiographic outcomes, were assessed. Mean follow-up was 5 years.

RESULTS

There was no implant breakage. At 5-year follow-up, the survivorship, free from revision for aseptic loosening and free of revision for any reason were 96% and 87%, respectively. At last follow-up (8 years), these figures were 92% and 71%, respectively. 31 implants were revised. The risk of revision for any cause was higher for extreme length metaphyseal implants, hazard ratio was 3.7 (95% CI, 1.82-7.52). A mean stem subsidence of 9 mm was noted in 37 cases; 4 were revised for aseptic loosening. The Harris Hip Score at final follow-up was 82.

CONCLUSIONS

At 5-year follow-up, the MFT implant showed a good survivorship and outcomes with no specific complications. Unlike literature reports, no specific complications occurred with this design. Stem junction positioning and therefore metaphyseal length may be key to optimise long-term survivorship. However, a longer follow-up is needed as implant breakage is more often seen after long implantation times.

A review of the design, manufacture, and outcomes of custom total joint replacement implants available in the United States

Custom total joint replacement (TJA) implants, specifically designed and manufactured for each patient, have emerged as surgeons seek to improve functional outcomes of primary total joint replacement, as well as treat patients with complex primary deformities, bone defects, and revision surgeries. The purpose of this review is to present the various custom total hip and knee arthroplasty implants available in the United States for primary and revision cases, so that surgeons can understand the design considerations and manufacturing processes of custom implants, as well as their performance compared to standard implants.

Last generation fluted modular titanium stem in revision hip arthroplasty: a narrative review of mid- and long-term outcomes

Background and Objective

Tapered fluted titanium stems (TFTS), were introduced to overcome proximal femur bone defects. They obtain stable fixation even in catastrophic proximal bone loss. Modular ones have the advantage to adjust length, rotation, off-set independently from the distal module. Short-term publications have been showing favorable outcomes burdened by an unacceptably high rate of stem failure. Still, there is a paucity of mid- and long-term reports. This narrative review aims at analyzing recent literature on modular TFTS with at least 5 years of minimum follow-up to gain a better understanding of implant survival, performance, and complications.

Methods

A search of the PubMed database was performed with selected key terms. Results were screened after the application of strict inclusion and exclusion criteria. Extracted data were subsequently evaluated to obtain an up-to-date overview of the results and complications of TFTS.

Key Content and Findings

Modular TFTS showed a consistent increase in patient reported outcomes that persists at 10 years and above. Femoral fractures were the most common intraoperative complication. Despite modularity, dislocation still occurs at a variable rate (1.2-12%). With revision for any cause as an endpoint, overall survival approaches 83% after 10 years of follow-up. If femoral revision only is evaluated, excellent survival rates (>95%) have been published. Stem subsidence over 5 mm was reported in less than 5% of patients, only 1 requiring femoral revision. The mean incidence of stem mechanical failure was 3.39%, although most breakages occurred in stems eventually retired from the market.

Conclusions

Satisfactory survival rates were observed, with an acceptable rate of complications. Stem mechanical failure, excluding those stems eventually retired from the market, remains a marginal event. Therefore, the use of modular TFTS in revision surgery is safe and effective even in the long term.

Clinical and radiological outcomes and analysis of failures of modular revisions stems at long-term follow-up: a systematic review and meta-analysis

Background

Increasingly hip replacements at young age exposes the patient to an increased risk of failure of the implant over the years. In case of failure, revision specific stems were designed to overcome bone loss. Modularity of these devices is an important resource for the surgeon as they allow the new implant to be better adapted to the patient's anatomy. The purpose of this systematic review is to provide data about the outcome at long-term follow-up (>8 years) of hip modular revision femoral stems.

Methods

This systematic review and meta-analysis were conducted following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement guidelines. PubMed and Google Scholar databases were systematically and independently searched, according to the inclusion and exclusion criteria. Two reviewers performed the data extraction independently. In case of disagreement, the senior authors were sought to resolve the divergences. Quality of the involved studies was evaluated with National Institute for Health and Care Excellence (NICE) guidelines (eight-item list) and the Newcastle-Ottawa scale (NOS). Primary and secondary outcomes were evaluated. The statistical analysis of this meta-analysis was performed by using Excel Microsoft and the software STATA.

Results

The primary outcome was the re-revision rate of modular revision stems at long-term follow-up. It ranged from 1.4% to 45.6%: random effect pooled estimate was 5.5% [95% confidence interval (CI): 4% to 7%], with a I2 of 12.3% (P=0.332). Mean Harris Hip Score (HHS) was 83 [min: 79; max: 87.6; standard deviation (SD): 3.55]. Secondary evaluated outcomes were: subsidence >5 mm, rate of periprosthetic infection or fractures (intra- and post-operative) and dislocations. The mean value for the NICE tool was 5.5 (SD: 1.13) and 7.3 (SD: 0.79) for the NOS tool. The survival rate was >90% at long-term follow-up (min: 60%; max: 97%).

Conclusions

The modular femoral revision stems have demonstrated good long-term reliability and efficacy. This meta-analysis demonstrates that the re-revision rate after 8 years of follow-up is low and 90% of the implants did not fail.

Cemented versus uncemented stems for revision total hip replacement: A systematic review and meta-analysis

BACKGROUND

The popularity of uncemented stems in revision total hip arthroplasty (THA) has increased in the last decade.

AIM

To assess the outcomes of both cemented and uncemented stems after mid-term follow up.

METHODS

This study was performed following both the Preferred Reporting Items for Systematic Reviews and Meta-analyses Statement and the Cochrane Handbook for systematic reviews and meta-analysis guidelines. Articles were chosen irrespective of country of origin or language utilized for the article full texts. This paper included studies that reviewed revision THA for both cemented or uncemented long stems.

RESULTS

Three eligible studies were included in the meta-analysis. Analysis was conducted by using Review Manager version 5.3. We computed the risk ratio as a measure of the treatment effect, taking into account heterogeneity. We used random-effect models. There were no significant differences found for intraoperative periprosthetic fractures [risk ratio (RR) = 1.25; 95% confidence interval (CI): 0.29-5.32; P = 0.76], aseptic loosening (RR = 2.15, 95%CI: 0.81-5.70; P = 0.13), dislocation rate (RR = 0.50; 95%CI: 0.10-2.47; P = 0.39), or infection rate (RR = 0.99, 95%CI: 0.82-1.19; P = 0.89), between the uncemented and the cemented long stems for revision THA after mid-term follow-up.

CONCLUSION

This study has evaluated the mid-term outcomes of both cemented and uncemented stems at first-time revision THA. In summary, there were no significant differences in the dislocation rate, aseptic loosening, intraoperative periprosthetic fracture and infection rate between the two cohorts.

Modular Proximal Body Exchange for Re-revision Total Hip Arthroplasty: Rarely Utilized and Moderately Successful

BACKGROUND

Modular fluted tapered stems (MFTSs) are commonly used in revision total hip arthroplasty (THA) and provide the option of exchanging the proximal modular portion to address future surgical problems without complete femoral revision. We are unaware of any data documenting the frequencies, indications, and outcomes of modular proximal body exchange in re-revision THA.

METHODS

Between 1997 and 2019, we performed 57 modular proximal body exchanges among 8,079 revision THAs at our institution. Indications and outcomes were documented at a mean follow-up of 3.4 years (range, 0 to 12.8).

RESULTS

Modular proximal body exchange was performed on 47 of 1375 (3%) of MFTSs implanted. The indications for all 57 modular proximal body exchanges performed during the study period were dislocation in 30 (53%), partial resection for periprosthetic joint infection (PJI) in 13 (23%), modular junction failure in 8 (14%), surgical exposure in 4 (7%), and concurrently with trochanteric osteotomy nonunion fixation in 2 (4%). At final follow-up, subsequent re-revisions occurred in 10 of 30 (33%) of modular proximal body exchanges indicated for dislocation and in 5 of 13 of those indicated for PJI. One modular junction subsequently fractured after modular proximal body exchange.

CONCLUSIONS

Modular proximal body exchange of a MFTS is an uncommon procedure most often performed for treatment of hip dislocation or PJI. It is moderately successful with approximately one-third of cases requiring subsequent re-revision. This procedure is often performed with modular component exchange alone, but can also be helpful to facilitate complex acetabular exposure. These data provide useful information to surgeons and patients undergoing this procedure.

The Early- to Mid-term Outcome of Novel Cementless Modular Femoral Stem in East Asian Patients

Background

Early firm fixation of the femoral implant is crucial in total hip arthroplasty (THA) with unstable metaphysis or a large degree of femoral bone loss. This study aimed to evaluate the outcomes of THA using a novel cementless modular, fluted, tapered stem in such cases.

Methods

From 2015 to 2020, 105 hips (101 patients) had surgery performed by two surgeons at two tertiary hospitals using a cementless modular, fluted, tapered stem for periprosthetic fractures, massive bone loss, prosthetic joint infection sequelae, or tumorous condition. Clinical outcomes, radiographic results, and survivorship of the implant were evaluated.

Results

The average follow-up period was 2.8 years (range, 1-6.2 years). The Koval grade was 2.7 ± 1.7 preoperatively and maintained at 1.2 ± 0.8 at the latest follow-up. The plain radiograph showed bone ingrowth fixation in 89 hips (84.8%). The average stem subsidence at postoperative 1 year was 1.6 ± 3.2 mm (range, 0-11.0 mm). Five reoperations (4.8%) were needed, including 1 for acute periprosthetic fracture, 1 for recurrent dislocation, and 3 for chronic periprosthetic joint infection. Kaplan-Meier survivorship with reoperation for any reason as the endpoint was 94.1%.

Conclusions

The early- to mid-term results of THA with the novel cementless modular, fluted, tapered THA stem system were satisfactory clinically and radiologically. The shortcomings inherent to its modularity were not identified. This modular femoral system may provide adequate fixation and be a practical option in the setting of complicated THA.

Long-Term Outcomes of Revision Total Hip Arthroplasty Using a Tapered and Fluted Modular Stem: A Mean Follow-Up of 16 Years

BACKGROUND

Tapered modular stems are increasingly used in revision total hip arthroplasty (THA) with deficient femoral bone stock. This study aimed to report the long-term outcomes of revision THA using a tapered and fluted modular stem.

METHODS

Between December 1998 and February 2006, 113 revision THAs (110 patients) were performed with a tapered and fluted modular stem at a single institution. Hip radiographs were used to identify stem subsidence, stability, and femoral radiolucency. Final outcomes were assessed in 72 hips (70 patients), with a minimum follow-up of 10 years.

RESULTS

The mean follow-up duration was 16 years (range, 10-23). At the final evaluation, the Harris Hip Score improved from a mean of 41 points (range, 10-72) preoperatively to 83 points (range, 56-100) (P < .001). Six femoral re-revisions were performed for the following reasons: 1 aseptic loosening, 2 stem fractures, and 3 infections. One stem fracture occurred at the modular junction after 14 years, and the other at a more distal location after 15 years. Stem subsidence was >5 mm in 6 hips (9.1%), but secondary stability was achieved in all stems. Osseointegration was observed in 63 (95.5%) hips. Stem survivorship was 91.1% with an end point of any re-revision and 94.6% for aseptic re-revision.

CONCLUSION

A tapered and fluted modular stem demonstrated excellent implant survivorship with reliable bony fixation at a mean follow-up of 16 years. This type of stem can be a durable option for revision THA in patients who have femoral defects.

EBRA Migration Analysis of a Modular, Distally Fixed Stem in Hip Revision Arthroplasty: A Clinical and Radiological Study

Background: Massive osteolysis of the proximal femur makes stem revision a challenging procedure. EBRA-FCA provides the opportunity to determine stem migration, which is considered a predictive factor for implant survival. In this study, we aimed to analyze the migration behavior of a modular, distally fixed reconstruction prosthesis. Methods: Applying a retrospective study design, we reviewed all consecutive patients who received a cementless MP reconstruction prosthesis (Waldemar Link GmbH & Co. KG, Hamburg, Germany) at our Department between 2005 and 2019. We reviewed medical histories and performed radiological measurements using EBRA-FCA software. Results: A total of 67 stems in 62 patients (female 26; male 36) fulfilled our inclusion criteria. Mean age at surgery was 68.0 (range 38.7−88.44) years. EBRA migration analysis showed a median subsidence of 1.6 mm (range 0.0−20.6) at 24 months. The angle between stem and femur axis was 0.3° (range 0.0°−2.9°) at final follow-up. No correlation between body mass index and increased subsidence was found (p > 0.05). Overall revision-free rate amounted to 92.5% and revision-free rate for aseptic loosening to 98.5%. Furthermore, no case of material breakage was detected. Conclusions: In summary, the MP reconstruction prosthesis showed low subsidence and reduction in the migration rate over the investigated follow-up. Based on this, the modular stem can be considered as a good therapy option in challenging stem revisions offering various options to address the individual anatomical situation.