An analysis of stably fixed femoral components retained during revision total hip arthroplasty

The impact of retaining the femoral stem in revision total hip arthroplasty: a systematic review, meta-analysis, and meta-regression

INTRODUCTION

The management of well-fixed femoral stems in revision total hip arthroplasty (rTHA) remains a subject of debate, with concerns over potential complications arising from stem retention. This study aimed to investigate the re-revision rates due to aseptic loosening of the stem, overall re-revision rates, dislocation rates, and factors influencing these outcomes in rTHA with a retained well-fixed femoral stem.

MATERIALS AND METHODS

A systematic search was conducted across several databases including PubMed, EMBASE, and CENTRAL to identify pertinent publications from their inception through 2023. We specifically focused on studies that reported outcomes of rTHA with retained well-fixed femoral stems. The study designs incorporated in our research encompassed both cohort studies and case series studies. Thirty-five studies involving isolated acetabular revision and retaining the stem were included, representing a total of 3497 patients. Data extraction was tailored to the study questions. Meta-analyses, meta-regression, and subgroup analyses were conducted to evaluate the outcomes and their relationship with various factors. Pooled results, meta-regression, and subgroup analyses were performed using random-effects models. To assess and reduce bias, we employed Egger's test and the trim and fill method.

RESULTS

The meta-analysis included 3497 patients with a mean follow-up of 9.28 years. The 10-year risk of re-revision after retaining femoral stem using highly cross-linked polyethylene was 1.7% (95% CI 1.1%-2.3%; I2: 60%) for stem aseptic loosening and 8.8% (95% CI 6.2%-11.4%; I2: 78%) overall re-revision. Dislocation risk was 5.7% (95% CI 4.1-7.0%; I2: 61%). Ceramic heads showed lower stem failure risk than metal heads in long-term follow-ups (P < 0.001). The posterolateral approach in revision surgery resulted in better long-term outcomes compared to the direct lateral approach (P < 0.001). Follow-up duration, timeline of study, Harris Hip Score, type of stem fixation, femoral head material, BMI, age, stem age, and surgical approach were evaluated as influential factors on these outcomes.

CONCLUSION

The re-revision rate due to aseptic loosening of the retained stem during rTHA was found to be significantly low, supporting the idea of retaining well-fixed stems during rTHA. The overall re-revision and dislocation rates also presented comparable or better outcomes to prior studies. A range of factors, including the use of highly cross-linked polyethylene and ceramic femoral heads, was found to influence these outcomes.

LEVEL OF EVIDENCE

IV.

PROSPERO REGISTRATION NUMBER

CRD42022351157.

Dual Mobility Articulation in Total Hip Arthroplasty: Mixed Femoral and Acetabular Components are a Feasible Option

BACKGROUND

The utilization of a different manufacturer for the prosthetic femoral head and the polyethylene insert in dual mobility (DM) for total hip arthroplasty (THA) may be necessary, especially in the revision setting. However, there is no data in the literature about this application. This study evaluated the outcomes of mixed manufacturer components, with the hypothesis that there would be no difference in measured outcomes compared to matched components.

METHODS

The DM articulations implanted during THA revision were retrospectively reviewed from 2011 to 2017. The study group was then stratified into 2 cohorts: matching components or mixed components. Of 130 hips included in the study with DM articulations with average follow-up of 7 years, 103 had mixed and 27 had matching manufacturer components. Rates of all cause reoperation and revision, intraprosthetic dislocation, dislocation, and aseptic loosening were compared using Chi-squared and Fisher's exact test; survival analysis was also performed.

RESULTS

Matched and mixed manufacturer implants had no significant difference between all cause reoperation (33 versus 25.2%), dislocation (14.8 versus 7.7%), and aseptic loosening (3.7 versus 3.9%), respectively. Higher rates of intraprosthetic dislocation (11 versus 0.97%) were observed in the matching component cohort. Survival analysis showed similar outcomes at 2, 5, and 10 years.

CONCLUSIONS

Mixed-component DM articulations show similar results compared to matching components. The off-label use of mixed manufacture DM articulation in THA is a feasible and safe option in the correct patient. Furthermore, when encountering a well-fixed femoral stem or acetabular shell, the use of a mixed component DM articulations may reduce the morbidity for the patient and prevent revision of all components.

Survivorship of the retained femoral component after revision total hip arthroplasty: A systematic review and meta-analysis

Objective

This systematic review and meta-analysis aimed to estimate re-revision rates of retained femoral components after revision of total hip arthroplasty (THA).

Methods

Papers were searched in the PubMed, Embase, Web of Science, and Cochrane Library databases with predetermined keywords from January 2000 to January 2022. The studies reporting the re-revision rates of retained stems after revision THA were identified. Pooled rates of re-revision for any reason and aseptic loosening were calculated using a random-effects model or a fixed-effects model based on the results of heterogeneity assessment after the Freeman–Tukey double-arcsine transformation. A meta-regression was performed to explore potential sources of heterogeneity.

Results

There were 20 studies with 1,484 hips that received the isolated cup revision with the femoral component retained. The pooled re-revision rate of retained stems was 1.75% [95% confidence interval (CI) 0.43%–3.65%]. The re-revision rate of retained stems due to aseptic loosening was 0.62% (95% CI, 0.06%–1.55%). The meta-regression showed that the fixation type (cemented or cementless) was related to the re-revision rate for any reason and the re-revision rate for aseptic loosening.

Conclusion

Based on the existing evidence, the isolated cup revision with a stable stem in situ yields low re-revision rates. The cement status of retained stems may influence the survivorship of stems.

The Survival of Well-Fixed Cementless Femoral Component After Isolated Acetabular Component Revision

BACKGROUND

It remains controversial whether isolated acetabular component revision or both component revision surgeries should be performed in patients with stable femoral component. The present study aimed to evaluate the survival of patients with unrevised stable uncemented femoral stem who underwent isolated acetabular component revision.

MATERIAL AND METHODS

A retrospective analysis was conducted in patients who underwent isolated acetabular component revision and had stable uncemented femoral component during revision hip arthroplasty between February 1998 and December 2009. Demographic data of the patients included age, previous surgery, complications, duration between primary and revision surgery, and duration between revision and latest follow-up. Functional results were analyzed using Harris Hip Score (HHS).

RESULTS

Fifteen hips of thirteen patients were included in the study with a mean age of 62.08 ± 12.9 years. Average time from THA to the isolated acetabular revision was 9.2 ± 3.48 years. Average follow-up time from revision to the latest follow-up was 12.39 ± 2.68 years, and femoral components had been followed for an average of 21.6 ± 4.06 years since the time of implantation. Average HHS of the patients were 53 before revision surgery and 81.9 at the last follow-up (p < 0.001). The 10-year survival rate of patients who underwent revision in the femoral component was 100%, whereas their 15-year survival rate was 93.3%. None of the acetabular components required revision.

CONCLUSION

Isolated revision of acetabular component may be considered if there is stable uncemented femoral component in revision THA. Acetabular reconstruction quality, acetabular and unrevised femoral component survival are not affected by retaining well-fixed femoral component.

LEVEL OF EVIDENCE

4, retrospective cohort study.

Adapter sleeves are essential for ceramic heads in hip revision surgery

BACKGROUND

Removing a head during isolated acetabular revision surgery can cause damage to the stem taper surface from extraction tool contact. Implanting a ceramic head on the damaged stem taper might elevate the fracture risk, which can be mitigated with the use of titanium adapter sleeves. The aim of this study was to investigate whether the improved fracture strength of modern generation ceramic heads allows the direct implantation on damaged stem tapers without an adapter sleeve.

METHODS

Finite element models of taper junctions with and without adapter sleeve were generated. Different stem taper damages were modelled to investigate the influence on the ceramic head fracture load under axial compression.

FINDINGS

Heads without adapter sleeves exhibited slightly higher or equal fracture strengths compared with sleeved heads for most scenarios. However, a small metal elevation on the stem taper caused a drastic decrease of the fracture strength if no adapter sleeve was used (-96%). The sleeved head was not influenced by the metal elevation damage.

INTERPRETATION

Adapter sleeves are essential to ensure patient safety and prosthesis longevity whenever implanting ceramic heads on used stem tapers.

Long-Term Survival of Retained Cementless Hip Stems at an Average of 13 Years After Isolated Cup Revision

BACKGROUND

Cementless stems demonstrate excellent long-term survival, but little is known about the long-term survival rate of the stem after isolated cup revision. The aim of the present retrospective cohort study was to determine the long-term survival rate of cementless stems retained after prior cup revision.

METHODS

We reviewed the clinical and radiographic results of 119 total hip arthroplasties (THAs) utilizing a cementless, grit-blasted, tapered titanium femoral stem that were performed in 113 patients between January 1985 and December 1989. The mean age at the time of the primary THA was 52 years (range, 16 to 74 years) and the mean time between primary THA and cup revision was 13 years (standard deviation [SD], 6 years; range, 0 to 30 years). At the time of the latest follow-up, no patient was lost to follow-up, 36 patients representing 37 hips had died, and 11 hips in 11 patients had required stem revision. The mean follow-up was 13 years following cup revision (SD, 6 years; range, 0 to 28 years). A competing risk analysis was performed to estimate the survival of the stem after isolated cup revision, with death being the competing risk factor.

RESULTS

At 20 years after cup revision, the survival rate of retained stems was 89% (95% confidence interval [CI], 79% to 94%) for the end point of stem revision for any reason and 97% (95% CI, 91% to 99%) for the end point of stem revision for aseptic loosening.

CONCLUSIONS

The long-term survival of cementless stems retained after cup revision was excellent. Well-fixed cementless stems should be retained during cup revision for aseptic loosening.

LEVEL OF EVIDENCE

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

Acetabulum-Only Revision Total Hip Arthroplasty Is Associated With Good Functional Outcomes and Survivorship

BACKGROUND

The coexistence of a stable femoral and a loose acetabular component may pose a clinical dilemma for the surgeon. Our study aims at comparing the intermediate functional outcomes and survivorship of acetabulum-only revision total hip arthroplasty (ArTHA) with an age-matched and gender-matched total revision THA (TrTHA) group.

METHODS

We retrospectively reviewed prospectively collected data on the pain, function, and total Harris Hip Scores (HHS) and complication profile for ArTHA and TrTHA cohorts from our regional arthroplasty database. Kaplan-Meier survivorship, with the need for repeat revision surgery as the end point, was used for survival analysis.

RESULTS

Among 538 cases, there were fewer acute medical complications in ArTHA and a similar dislocation rate for both cohorts. Preoperative HHS for pain, function, and total were better in the ArTHA cohort, but only the function score reached statistical significance. No significant differences in subsequent years for all aspects of HHS, except the function score was significantly better in the ArTHA cohort at year 1. And 10.0% of ArTHAs and 7.8% of TrTHAs had required rerevision. The 5-year survivorship was 90.3% (95% confidence interval ± 2.1%) for the ArTHA cohort and 92.7% (95% confidence interval ± 1.8%) for the TrTHA cohort (P = .394). The ArTHA with posterior approach (n = 118) group had the lowest dislocation rate and the best trend of functional outcomes.

CONCLUSION

ArTHA can provide similar functional outcomes and dislocation rate to TrTHA, with an acceptable rerevision rate. The posterior approach in this study was not associated with a significant dislocation rate.

Isolated acetabular revision with femoral stem retention after bipolar hip arthroplasty

INTRODUCTION

In bipolar hemiarthroplasty, migration of the outer cup component into the acetabular cup, with evidence of severe osteolysis in the acetabulum, commonly occurs without loosening of the femoral component. The merits of retaining the stable femoral component in these cases have been debated. Our study aimed to determine whether revision of the acetabular component in isolation could be successfully performed.

MATERIALS AND METHODS

The data of 54 patients (61 hips), 44 women, and 10 men, aged 67.7 (range 47-86) years at the time of the index revision, were analyzed. The average time from primary operation to revision surgery was 14.9 (range 1.0-27.0) years, with an average follow-up time after revision of 5.2 (range, 1.0-18.7) years. Indications for acetabular revision included migration of the outer cup component (N = 55), disassembly of the bipolar cup (N = 4), and recurrent dislocation (N = 2). Fixation of the femoral stem was cementless in 49 hips and cemented in 12. Bone grafting for osteolysis of the proximal femur around the stem was performed in six hips. An acetabular reinforcement ring with a cemented cup was used in 31 hips, with cementless cup fixation in 29 hips, and cemented cup in one case.

RESULTS

On average, the Harris hip score improved from 57.0 ± 21.6 to 87.4 ± 6.40 points after revision. Two cases of femoral periprosthetic fracture were treated with osteosynthesis 3 year post-revision. There was no evidence of loosening of the femoral stem or subsidence, with a non-progressive radiolucent line <2 mm identified in one case. There was no incidence of dislocation or deep infection, and all components were judged to be stable at the final follow-up.

CONCLUSION

Isolated acetabular revision can be reliably performed in cases of failed bipolar hemiarthroplasty with a well-fixed femoral component.

Digital tomosynthesis with metal artifact reduction for assessing cementless hip arthroplasty: a diagnostic cohort study of 48 patients

OBJECTIVES

For postoperative imaging assessment of cementless hip arthroplasty, radiography and computed tomography (CT) were restricted by overlapping structures and metal artifacts, respectively. A new tomosynthesis with metal artifact reduction (TMAR) is introduced by using metal extraction and ordered subset-expectation maximization (OS-EM) reconstruction. This study investigated the effectiveness of TMAR in assessing fixation stability of cementless hip arthroplasty components.

MATERIALS AND METHODS

We prospectively included 48 consecutive patients scheduled for revision hip arthroplasty in our hospital, with 41 femoral and 35 acetabular cementless components available for evaluation. All patients took the three examinations of radiography, CT, and TMAR preoperatively, with intraoperative mechanical tests, and absence or presence of osteointegration on retrieved prosthesis as reference standards. Three senior surgeons and four junior surgeons evaluated these images independently with uniform criteria.

RESULTS

For TMAR, 82 % diagnoses on the femoral side and 84 % diagnoses on the acetabular side were accurate. The corresponding values were 44 and 67 % for radiography, and 39 % and 74 % for CT. Senior surgeons had significantly higher accuracy than junior surgeons by radiography (p < 0.05), but not by TMAR or CT.

CONCLUSIONS

By minimizing metal artifacts in the bone-implant interface and clearly depicting peri-implant trabecular structures, the TMAR technique improved the diagnostic accuracy of assessing fixation stability of cementless hip arthroplasty, and shortened the learning curve of less experienced surgeons.

LEVEL OF EVIDENCE

Level II, diagnostic cohort study.

Complications Are Not Increased With Acetabular Revision of Metal-on-metal Total Hip Arthroplasty

BACKGROUND

Isolated revision of the acetabular component in the setting of total hip arthroplasty has an increased risk of dislocation. With local soft tissue destruction frequently associated with failed metal-on-metal (MoM) bearings, it is presumed that acetabular revision of these hips will have even greater risk of complications. However, no study directly compares the complications of MoM with metal-on-polyethylene (MoP) acetabular revisions.

QUESTIONS/PURPOSES

In the context of a large database analysis, we asked the following questions: (1) Are there differences in early medical or wound complications after isolated acetabular revision of MoM and MoP bearing surfaces? (2) Are there differences in the frequency of dislocation, deep infection, and rerevision based on the bearing surface of the original implant?

METHODS

A review of the 100% Medicare database from 2005 to 2012 was performed using International Classification of Diseases, 9th Revision and Current Procedural Terminology codes. We identified 451 patients with a MoM bearing and 628 patients with a MoP bearing who had an isolated acetabular revision and a minimum followup of 2 years. The incidence, odds ratios, and 95% confidence intervals for early medical or wound complications were calculated using a univariate analysis at 30 days with patient sex and age group-adjusted analysis for blood transfusion. The incidence, odds ratio, and 95% confidence intervals for dislocation, deep infection, and rerevision were calculated using a univariate analysis at 30 day, 90 days, 1 year, and 2 years using a subgroup analysis with the Cochran-Mantel-Haenszel test to adjust for patient gender and age groups.

RESULTS

There were no differences between the MoM and MoP isolated acetabular revisions in the incidence of 30-day local complications. There was a greater risk of transfusion in the MoP group than the MoM group (134 of 451 [30%] versus 230 of 628 [37%]; odds ratio [OR], 0.731; 95% confidence interval [CI], 0.565-0.948; p = 0.018). There were no differences at 2 years between the MoM and MoP acetabular revisions in the incidence of dislocation, infection, or rerevision. When analyzed by patient sex and age group, there were more infections in the age 70 to 79 years MoP group compared with MoM (10 of 451 [5%] versus 29 of 628 [10%]; OR, 4.47; CI, 1.699-11.761; p = 0.001).

CONCLUSIONS

There were high rates of dislocation, infection, and rerevision in both revision cohorts. The rate of dislocation was not greater after acetabular revision of MoM bearings at 2 years. Based on these findings, clinicians should counsel these patients preoperatively about the risks of these complications. Dual-mobility and constrained components have specific advantages and disadvantages in these settings and should be further studied.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Prevalence and Risk Factors of Spine, Shoulder, Hand, Hip, and Knee Osteoarthritis in Community-dwelling Koreans Older Than Age 65 Years

BACKGROUND

Osteoarthritis (OA) is common and disabling among older patients around the world. Data exploring the prevalence and risk factors of OA are of paramount importance in establishing healthcare policies. However, few studies have evaluated these topics among Asian populations.

QUESTIONS/PURPOSES

This study was conducted to determine the prevalence and risk factors of radiographic OA in the spine, shoulder, hand, hip, and knee in Koreans older than age 65 years.

METHODS

A simple random sample (N = 1118) was drawn from a roster of elderly individuals older than age 65 years in Seongnam. Of the 1118 invited subjects, 696 (males = 298, females = 398) participated in this study (a response rate of 62%). The mean age of respondents was 72 ± 5 years (range, 65-91 years). Radiographs of the lumbar spine, shoulder, hand, hip, and knee were taken and afterward evaluated for radiographic OA. The Kellgren-Lawrence grading system was used for all mentioned joints, and radiographic OA was defined as Grade 2 changes or higher. The association of sex, aging, and obesity with OA in each of the mentioned joints was determined with the help of multivariate logistic regression.

RESULTS

The highest prevalence of radiographic OA was seen in the spine (number of subjects with OA/number of whole population = 462 of 696 [66%]) followed by the hand (415 of 692 [60%]), knee (265 of 696 [38%]), shoulder (36 of 696 [5%]), and hip (15 of 686 [2%]). Female sex was associated with knee OA (odds ratio [OR], 5.7; 95% confidence interval [CI], 3.9-8.4; p < 0.001) and hand OA (OR, 2.3; 95% CI, 1.6-3.1; p < 0.001), and male sex was associated with spine OA (OR, 0.7; 95% CI, 0.5-1.0; p = 0.025). Aging was associated with radiographic OA in the spine, knee, and hand (OR per 5-year increments, 1.3 [95% CI, 1.1-1.6; p = 0.001], 1.6 [95% CI, 1.4-1.9; p < 0.001], and 1.4 [95% CI, 1.2-1.7; p < 0.001]), respectively) but not associated with OA in the hip and shoulder. Obesity was associated with knee OA (OR, 3.4; 95% CI, 2.4-5.0; p < 0.001) and spine OA (OR, 1.5; 95% CI, 1.1-2.2; p = 0.014) but not with OA in other joints.

CONCLUSIONS

OA of the spine, hand, and knee is likely to become a major public health problem rather than shoulder and hip OA in Korea. Associations of demographic factors with radiographic OA differed among each joint, and that would be valuable information to assess the role and influence of risk factors of OA in various joints.

LEVEL OF EVIDENCE

Level III, prognostic study.

One-component revision in total hip arthroplasty: the fate of the retained component

The purpose of the present study was to evaluate the long-term outcome of the unrevised part in one-component total hip arthroplasty revision (index operation). Forty-four patients (46 hips) with a mean age of 58years at the time of the index operation were included. At the final follow-up, 4 of the 19 (21%) unrevised acetabular components and 6 of the 27 (22%) unrevised femoral components were subsequently revised at a mean time of 14 and 11years from the index operation, and 22 and 24years from the primary operation, respectively. We concluded that revision of a stable component is not justifiable on the basis of its long duration in use or non-ideal position or possible loosening on radiographs.

The use of ceramic-on-ceramic bearings in isolated revision of the acetabular component

The practice of removing a well-fixed cementless femoral component is associated with high morbidity. Ceramic bearing couples are low wearing and their use minimises the risk of subsequent further revision due to the production of wear debris. A total of 165 revision hip replacements were performed, in which a polyethylene-lined acetabular component was revised to a new acetabular component with a ceramic liner, while retaining the well-fixed femoral component. A titanium sleeve was placed over the used femoral trunnion, to which a ceramic head was added. There were 100 alumina and 65 Delta bearing couples inserted. The mean Harris hip score improved significantly from 71.3 (9.0 to 100.0) pre-operatively to 91.0 (41.0 to 100.0) at a mean follow up of 4.8 years (2.1 to 12.5) (p < 0.001). No patients reported squeaking of the hip. There were two fractures of the ceramic head, both in alumina bearings. No liners were seen to fracture. No fractures were observed in components made of Delta ceramic. At 8.3 years post-operatively the survival with any cause of failure as the endpoint was 96.6% (95% confidence interval (CI) 85.7 to 99.3) for the acetabular component and 94.0% (95% CI 82.1 to 98.4) for the femoral component. The technique of revising the acetabular component in the presence of a well-fixed femoral component with a ceramic head placed on a titanium sleeve over the used trunnion is a useful adjunct in revision hip practice. The use of Delta ceramic is recommended.

Modular sleeves with ceramic heads in isolated acetabular cup revision in younger patients-laboratory and experimental analysis of suitability and clinical outcomes

PURPOSE

One possibility in hip arthroplasty revisions is to combine a modular ceramic head with an adapter or sleeve in isolated acetabular cup replacement. This study consisted of an experimental part to analyse the reliability of taper damage predictions, and a clinical part to analyse the outcomes of modular ceramic head implantation in a case series of isolated cup replacements.

METHODS

Analysis of scratch size on 11 explanted hip stems were examined macroscopically and by stereomicroscopy to classify damage to the conical taper. The second part consisted of a prospective analysis of isolated cup revisions using a modular ceramic head, performed in two orthopedic centres.

RESULTS

Analysis of scratch size on the taper yielded inter-observer correlations of 0.545-0.909; comparison with stereomicroscopic data recordings yielded a moderate correlation, with values between 0.545 and 0.090. The clinical study included 47 isolated acetabular cup revisions involving modular ceramic heads. Ceramic head failure did not occur during the average clinical and radiological observation period of 26 months. Mean Harris Hip Score (HHS) at follow-up was 70 points.

CONCLUSION

From these results, it can be concluded that damage to the implanted stem taper cannot be reliably predicted intraoperatively. Nevertheless, the clinical outcomes did show that there were no problems with the ceramic heads over the short observation period. The application of modular ceramic heads in younger patients requiring isolated cup replacement requires proper risk-benefit analysis, but is possible and appears to be a safe procedure.