Incidence,Risk Factors,and Outcome of Ceramic-On-Ceramic Bearing Breakage in Total Hip Arthroplasty

BackgroundCeramic-on-ceramic bearing breakage is a rare but significant complication of total hip arthroplasty. This study aimed to identify risk factors for breakage and to determine the outcome of different revision options.MethodsAll ceramic-on-ceramic primary total hip arthroplasty procedures reported to the Australian Joint Replacement Registry from September 1999 to December 2019 were included. Procedures were subdivided into alumina or mixed ceramic (alumina/zirconia). All breakages were identified. The association between ceramic type and head size was assessed. Subsequent revision rates were compared and cause of revision assessed.ResultsThere were 23,534 alumina and 71,144 mixed ceramic procedures. Breakage was the reason for 1^st revision in 84 alumina (5.27% of all revisions and 0.36% of procedures) and 56 mixed ceramic procedures (2.46% of all revisions; 0.08% of procedures). Alumina had a higher breakage rate than mixed ceramic (HR 2.50 (95% CI 1.75, 3.59), P < .001), and breakage was higher for 36-38mm head sizes using alumina (HR 2.84 (1.52, 5.31), P = .001). 17.8% of 2^nd revisions occur by 3 years, due to dislocation, infection, metal-related pathology, and loosening. A neck adapter sleeve did not reduce 2^nd revisions. Numbers were too low to compare revision bearing surface options.ConclusionCeramic breakage has reduced with mixed ceramics but has a 0.79/1000 incidence at 15-year follow-up. It is unclear what the risk factors are for modern ceramics with increasing head size a risk for alumina only. Risk of 2^nd revision is high and occurs early. The optimal revision option is unknown.     

A Meta-Analysis of Outcomes in Total Hip Arthroplasty Recipients Following Pelvic Irradiation

BackgroundAlongside advances in total hip arthroplasty (THA), innovations in the treatment of cancer have led to an increasing number of patients living with this devastating disease. Radiation therapy has well-documented clinical effects on bone health, leading to pelvic insufficiency fractures and osteonecrosis of the femoral head. The purpose of this meta-analysis is to report on THA outcomes in this patient population in an effort to determine if a need to change management exists during surgical planning.MethodsFollowing the Preferred Reporting Items for Systematic Review and Meta-Analysis protocols, a systematic review of published literature through August 5^th, 2018 was conducted. This resulted in 8 studies in which the primary outcome measures evaluated were rates of aseptic loosening and revision THA.ResultsAmong 232 hips at a weighted mean follow-up time of 52 months, the aseptic loosening rate was 10% and revision THA rate was 12%. Sub-analysis of 116 THAs with cementless cups demonstrated an aseptic loosening and revision THA rate of 8% and 10%, respectively.ConclusionThe findings of the present study indicate that THA recipients who have received radiation therapy to the pelvis before arthroplasty surgery have higher rates of aseptic loosening and revision THA when compared with previously published rates in healthy THA recipients. Additionally, it is possible that female THA recipients who have received pelvic irradiation may be at a higher risk for aseptic loosening and revision THA. Surgeons should counsel patients with a history of pelvic irradiation about their potentially higher risk for these complications.Level of EvidenceLevel I, meta-analysis, and systematic review.     

A Comparison of Revision Rates for Dislocation and Aseptic Causes Between Dual Mobility and Large Femoral Head Bearings in Primary Total Hip Arthroplasty With Subanalysis by Acetabular Component Size: An Analysis of 106,163 Primary Total Hip Arthroplasties

BackgroundDual mobility (DM) and large femoral head bearings (≥36 mm) both decrease the risk of dislocation in total hip arthroplasty (THA). There is limited comparable data in primary THA. This study compared the revision rates for dislocation and aseptic causes between DM and large femoral heads and subanalyzed by acetabular component size.MethodsData from the Australian Orthopedic Association National Joint Replacement Registry were analyzed for patients undergoing primary THA for osteoarthritis from January 2008 (the year of first recorded DM use) to December 2019. All DM and large femoral head bearings were identified. The primary outcome measure was the cumulative percent revision (CPR) for dislocation and for all aseptic causes. The results were adjusted by age, sex, and femoral fixation. A subanalysis was performed stratifying acetabular component diameter <58 m and ≥58 mm.ResultsThere were 4942 DM and 101,221 large femoral head bearings recorded. There was no difference in the CPR for dislocation (HR = 0.69 (95% CI 0.42, 1.13), P = .138) or aseptic causes (HR = 0.91 (95% CI 0.70, 1.18), P = .457). When stratified by acetabular component size, DM reduced the CPR for dislocation in acetabular component diameter <58 mm (HR = 0.55 (95% CI 0.30, 1.00), P = .049). There was no difference for diameter ≥58 mm. There was no difference in aseptic revision when stratified by acetabular component diameter.ConclusionThere is no difference in revision rates for dislocation or aseptic causes between DM and large femoral heads in primary THA. When stratified by acetabular component size, DM reduces dislocation for acetabular component diameter <58 mm.Level of EvidenceLevel III.     

Causes of Revision in Young Patients Undergoing Total Hip Arthroplasty

BackgroundThe purpose of this study was to identify reasons for revision of total hip arthroplasty (THA) in patients who underwent primary THA at or before the age of 35 years. We hypothesized that the reasons for revision in younger patients would be different from the general older population of patients undergoing THA because of the differences in diagnoses, complexity of deformities, and differences in activity level.MethodsData for 108 hips in 82 patients who underwent primary THA at our institution before the age of 35 years from 1982-2007 and subsequently underwent revision THA were reviewed. Operative reports and clinic notes were reviewed to determine baseline characteristics, reason for revision, timing of revision, and components revised.ResultsThe mean age at index surgery was 25.4 years, and mean time from index to revision surgery was 10.1 years. The most common preoperative diagnoses included avascular necrosis, juvenile idiopathic arthritis, developmental dysplasia of the hip, and posttraumatic arthritis. The most common reasons for revision were acetabular loosening (30.1%), femoral loosening (23.7%), and polyethylene wear (24.7%). 8.3% of patients underwent primary THA with highly cross-linked polyethylene, while the remainder of the patients underwent THA when conventional polyethylene was used. There was no statistically significant association between which component(s) were revised and initial fixation (ie cemented or uncemented prosthesis) (P = .26).ConclusionCauses of revision in this population appear to differ from the general THA population. In young patients, acetabular loosening, femur loosening, and polyethylene wear were the most common causes of revision. Instability and infection were less common compared with literature reports of causes of revision in older patients. Findings in this study may be useful in counseling young patients undergoing THA, though results were likely influenced by the use of conventional rather than highly cross-linked polyethylene in this cohort.     

Revision Risk of Total Hip Arthroplasty With Vitamin E Doped Liners: Results From the Danish Hip Arthroplasty Register

BackgroundVitamin E-doped cross-linked polyethylene (VEPE) liners were introduced in total hip arthroplasty (THA) to reduce wear and risk of aseptic loosening and liner fracture. We report this nationwide population-based study to investigate the safety of VEPE liners for THA compared to cross-linked annealed or remelted polyethylene (XLPE).MethodsWe included THAs from The Danish Hip Arthroplasty Register from January 1, 2008 to June 30, 2019, with uncemented cup, VEPE or XLPE liner, and metal or ceramic head. The outcome was revision due to (1) polyethylene-related endpoints (aseptic loosening, granuloma, osteolysis, or liner fractures) and (2) other endpoints.ResultsA total of 110,803 THAs were assessed for eligibility and 53,842 THAs (46,645 patients) were included in the study: 5069 (9.4%) THAs with a VEPE liner and 48,773 (91.6%) with a XLPE liner. Median observation time was 5.48 (interquartile range 3.80-7.15) years for VEPE and 4.85 (interquartile range 2.68-7.76) for XLPE. VEPE had a lower risk of revision for polyethylene-related endpoints compared to XLPE (hazard ratio [HR] 0.60, 95% confidence interval 0.36-0.98) during complete follow-up. THAs with VEPE liners were associated with increased risk of any revision within the first 3 months (HR 1.62, 1.36-1.94), revision recorded as aseptic loosening within 3 months (HR 4.46, 2.26-8.80), and periprosthetic fracture within 3 months (HR 2.57, 1.98, 3.33).ConclusionVEPE liners had a lower risk of revision due to polyethylene-related endpoints, but a higher risk of all-cause revision within 3 months.     

No Difference in Dislocation Rates Comparing Large Diameter Jumbo Femoral Heads and Dual-Mobility Bearings in Revision Total Hip Arthroplasty

BackgroundDual-mobility (DM) bearings reduce instability in revision total hip arthroplasty (THA); however, DM bearings are costly and reports of corrosion have recently emerged. Furthermore, no study has compared DM to standard bearings with large diameter femoral heads ≥40-mm. This study’s purpose was to compare postoperative dislocation rates of standard and DM bearings with large femoral heads after revision THA.MethodsA retrospective review of 301 consecutive revision THAs was performed. The mean follow-up was 37.1 months. To isolate the effect of the double articulation, standard and DM bearings with femoral heads ≥40-mm were compared. Outcomes were postoperative dislocation and reoperation within 90 days.ResultsThe cohort consisted of 182 standard bearings and 75 DM bearings. There were no differences in revision indication comparing standard and DM bearings (P = .258). Overall dislocation rate was 8.6% (22 of 257). The dislocation rate was 5.7% for standard bearings with ≥40-mm femoral heads compared with 6.9% in DM bearings with ≥40-mm femoral heads (P = 1.000). In multivariate analysis, lower body mass index (odds ratio 1.72), female sex (odds ratio 2.01), and decreased outer femoral head diameter–to–cup component size ratio (odds ratio 1.64) were predictors of postoperative dislocation regardless of bearing type.ConclusionThis study showed no difference in dislocation rates between standard and DM bearings when comparing similar femoral head diameters of ≥40-mm used in revision THAs. Considering the cost and potential deleterious issues associated with additional interfaces, DM bearings should be used judiciously considering similar results may be achieved with single-articulation bearings using large femoral heads.Level of EvidenceLevel III.     

Conversion of Hip Hemiarthroplasty to Total Hip Arthroplasty Utilizing a Dual-Mobility Construct Compared With Large Femoral Heads

Background

Conversion of hemiarthroplasty to total hip arthroplasty (THA) has a historically high, up to 20%, postoperative dislocation rate. As such, dual-mobility (DM) constructs are an attractive option to mitigate this complication. We analyzed survivorship free of revision, complications, and clinical outcomes of hemiarthroplasties conversion to THAs utilizing DM constructs compared with large femoral heads (≥36 mm).

Outcome of Dual Mobility Constructs for Adverse Local Tissue Reaction Associated Abductor Deficiency in Revision Total Hip Arthroplasty

BackgroundTreatment of adverse local tissue reaction (ALTR) is challenging owing to high complications and poor outcomes after a revision surgery. As dislocation is the most common cause of reoperation, it is often necessary to use advanced articulations such as dual mobility. This study aims to evaluate the outcome and complication rates after revision surgery with dual mobility constructs, compared to constrained and conventional articulations in the setting of significant abductor deficiency due to ALTR.MethodsOut of a total of 338 revision total hip arthroplasties for ALTR, 234 patients with a significant tissue necrosis and abductor muscle insufficiency (grade 3) were evaluated. The complication rates after revisions were compared between 42 hips with dual mobility implants, 24 hips with constrained liners, 104 hips with large diameter heads (36-40 mm), and 64 hips with small diameter heads (≤32 mm).ResultsAfter an average of 4 years of follow-up (2.8-8.6), the dual mobility articulation had no dislocation, compared to 4.1% and 15.5% for constrained liner and conventional articulations, respectively (P < .001). Utilization of dual mobility and constrained liner cup also did not increase the risk of nondislocation complications, including periprosthetic joint infection and periprosthetic fracture (P = .18 and .52).ConclusionsThis study demonstrates significantly lower dislocation rates for dual mobility when compared to conventional articulations and comparable to constrained liners in cases of severe abductor deficiency due to ALTR, suggesting that dual mobility implants are viable surgical treatment alternatives to constrained liners to minimize dislocation during revision total hip arthroplasty in the setting of significant abductor deficiency due to ALTR.     

Dual Mobility for Monoblock Metal-on-Metal Revision—Is It Safe?

BackgroundRevision of monoblock metal-on-metal (MoM) total hip arthroplasty (THA) is associated with high complication rates. Limited revision by conversion to a dual mobility (DM) without acetabular component extraction may mitigate these complications. However, the concern for polyethylene wear and osteolysis remains unsettled. This study investigates the results of DM conversion of monoblock MoM THA compared to formal acetabular revision.MethodsOne hundred forty-three revisions of monoblock MoM THA were reviewed. Twenty-nine were revisions to a DM construct, and 114 were complete revisions of the acetabular component. Mean patient age was 61, 54% were women. Components used, acetabular cup position, radiographic outcomes, serum metal ion levels, and HOOS Jr clinical outcome scores were investigated.ResultsAt 3.9 years of follow-up (range 2-5), there were 2 revisions (6.9%) in the DM cohort, 1 for instability and another for periprosthetic fracture. Among the formal acetabular revision group there was a 20% major complication rate (23/114) and 16% underwent revision surgery (18/114) for aseptic loosening of the acetabular component (6%), deep infection (6%), dislocation (4%), acetabular fracture (3%), or delayed wound healing (6%). In the DM cohort, there were no radiographic signs of aseptic loosening, component migration, or polyethylene wear. One DM patient had a small posterior metadiaphyseal femur lesion that will require close monitoring. There were no other radiographic signs of osteolysis. There were no clinically significant elevations of serum metal ion levels. HOOS Jr scores were favorable.ConclusionLimited revision with conversion to DM is a viable treatment option for failed monoblock MoM THA with lower complication rates than formal revision. Limited revision to DM appears to be a safe option for revision of monoblock MoM THA with a cup in good position and an internal geometry free of sharp edges or articular surface damage. Longer follow-up is needed to demonstrate any potential wear implications of these articulations.     

Revision of Failed Metal-on-Metal Total Hip Arthroplasty: Midterm Outcomes of 203 Consecutive Cases

BackgroundMetal-on-metal (MoM) revisions have shown high rates of complications from aseptic loosening, deep infection, and dislocation. The purpose of this study is to report on outcomes and complications of a large consecutive series of patients who were revised for failed MoM total hip arthroplasty (THA).MethodsWe evaluated 188 patients (203 hips) who underwent revisions of failed MoM THA. Mean age at the revision was 60 years old. Gender was female in 112 hips (55%) and male in 91 hips (45%). Mean interval to failure after primary THA was 4.9 years (range, 0-18 years). The acetabular component was revised in 183 cases (92%). Clinical outcomes assessed included pain score and Harris hip score.ResultsMean follow-up from revision was 4.2 years. Harris hip score improved from 53.6 pre-revision to 73.5 at most recent follow-up (P < .001). Pain level significantly improved from 17.2 pre-revision to 32.8 post-revision (P < .001). Reoperations occurred in 28 (14%) hips. Re-revision was required in 16 hips (7.9%). The most common reasons for re-revision were aseptic loosening (5), dislocation (3), infection (2), and iliopsoas tendonitis (2). Re-revision was significantly higher in cases of pseudotumor. There was no difference in survival with ultraporous cups. Three hips required re-revision to custom triflange components. All-cause survival was 90.5% at 4.2 years. Metal ion levels significantly declined after revision.ConclusionRevisions of failed MoM THA showed improvements in clinical outcomes, but present significant surgical challenges and complications especially in cases with soft tissue damage and pseudotumor.     

Revision for Aseptic Loosening of Highly Porous Acetabular Components in Primary Total Hip Arthroplasty: An Analysis of 20,993 Total Hip Replacements

BackgroundHighly porous-coated titanium acetabular components have a high coefficient of friction and ultraporous surfaces to enhance bone ingrowth and osseointegration in total hip arthroplasty (THA). There have been concerns with the development of early radiolucent lines and aseptic loosening of highly porous acetabular components. It is unclear whether these concerns relate to a specific implant or the entire class. The aim of this study is to compare the revision rates for aseptic loosening of highly porous acetabular combinations in primary THA using data from a large joint replacement registry.MethodsData were retrieved from the Australian Orthopedic Association National Joint Replacement Registry for the study period September 1999 to December 2019. All primary THA procedures recorded and performed for osteoarthritis using the most common combinations for each highly porous acetabular component with highly cross-linked polyethylene and a 32-mm or 36-mm femoral head were included. The primary outcome measure was revision for aseptic loosening of the acetabular component. Results were adjusted for patient age and gender.ResultsThere were 20,993 primary THA procedures performed for osteoarthritis using a highly porous acetabular component across 6 combinations. Relative to the POLARSTEM/R3 (StikTite), the Exeter V40/Tritanium had a significantly higher risk of revision for aseptic loosening of the acetabular component (hazard ratio 0.21, 95% confidence interval 0.06-0.74, P = .014). There was no difference between any other highly porous acetabular component combination and no late revisions for aseptic loosening.ConclusionHighly porous-coated titanium acetabular components have low rates of aseptic loosening with long-term follow-up. A difference between components may exist.Level of EvidenceLevel III.     

THA for a Fractured Femoral Neck: Comparing the Revision and Dislocation Rates of Standard-head,Large-head,Dual-mobility,and Constrained Liners

BackgroundTHA is a reasonable surgical option for some patients with fragility fractures of the femoral neck, but it has the risk of prosthesis dislocation. The prosthesis combination that reduces the risk of dislocation and the rate of revision surgery is not known.Questions/purposesIn patients receiving primary THA for a femoral neck fracture, does (1) the rate of all-cause revision or (2) the reason for revision and rate of revision for dislocation differ among THA with a standard head size, large head size, dual mobility (DM), or constrained liner? (3) Is there a difference in the revision risk when patients are stratified by age at the time of surgery?MethodsData were analyzed for 16,692 THAs performed to treat fractures of the femoral neck reported in the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) from January 2008 to December 2018, as this included the first use of DM prostheses. The AOANJRR includes information on more than 98% of arthroplasty procedures performed in Australia. Most patients were female (72%) and the mean age was 74 years ± 11. There were 8582 standard-head prostheses, 5820 large-head prostheses, 1778 DM prostheses, and 512 constrained prostheses identified. The cumulative percent revision (CPR) was determined for all causes as well as CPR for dislocation. The time to the first revision was described using Kaplan-Meier estimates of survivorship, with right censoring for death or closure of the database at the time of analysis. The unadjusted CPR was estimated each year of the first 10 years for standard heads, 10 years for large heads, 8 years for constrained liners, and 7 years for DM prostheses, with 95% confidence intervals using unadjusted pointwise Greenwood estimates. The results were adjusted for age, sex, femoral fixation, and head size where appropriate and were considered by age groups < 70 and ≥ 70 years.ResultsWhen adjusted for age, sex, femoral fixation and head size, there was no difference in the rate of all-cause revision at 7 years for any of the four groups. There was no difference in the rate of all-cause revision when patients were stratified by < 70 or ≥ 70 years of age. Dislocation was the most common reason for revision (32%). When analyzing revision for dislocation alone, large-head THA had a lower rate of revision for dislocation compared with standard head (HR 0.6 [95% CI 0.4 to 0.8]; p < 0.001) and DM prostheses had a lower rate of revision for dislocation than standard head for the first 3 months (HR 0.3 [95% CI 0.1 to 0.7]; p < 0.004) but not after this time point.ConclusionThe Australian registry shows that there is no difference in the rate of all-cause revision for standard-head, large-head, DM prostheses or constrained liner THA after femoral neck fractures for all patients or for patients stratified into younger than 70 years and at least 70 years of age groups. Dislocation is the most common cause of revision. Large-head prostheses are associated with a lower revision risk for dislocation and DM prostheses have a lower rate of revision for dislocation than standard heads for the first 3 months only. Surgeons treating a femoral neck fracture with THA might consider a large head size if the diameter of the acetabulum will allow it and a DM prosthesis if a large head size is not possible. The age, life expectancy and level of function of patients with femoral neck fractures minimizes the potential long-term consequences of these prostheses. The lack of significant differences in survival between most prosthesis combinations means surgeons should continue to look for factors beyond head size and prosthesis to minimize dislocation and revision surgery.Level of EvidenceLevel III, therapeutic study.     

Etiology and Complications of Early Aseptic Revision Total Hip Arthroplasty Within 90 Days

BackgroundThe etiology, complications, and rerevision risks of early aseptic revision total hip arthroplasty (THA) within 90 days are insufficiently documented.MethodsA national insurance claims database (PearlDiver Technologies, Fort Wayne, IN) was queried for patients who underwent unilateral aseptic revision THA within 90 days of the index procedure using administrative codes. Patients who underwent revision for infection, without minimum 2-year follow-up, and younger than 18 years were excluded. This cohort was matched based on gender, age, and Charlson Comorbidity Index to a control group of patients who underwent primary THA without revision within 90 days. Two-year rerevision and 90-day complication rates were recorded. Chi-square and Fisher exact tests were used as appropriate for statistical comparison.ResultsFour hundred two patients met the inclusion criteria for early aseptic revision within 90 days of the index procedure and were matched to the control group. The overall 2-year rerevision rate was higher in the early revision group compared with control group (14.9% vs 2.5%, P < .001). Complications within 90 days occurred more frequently in the early revision group, including blood transfusion (10.2% vs 3.2%, P < .001), deep vein thrombosis (9.0% vs 3.2%, P = .001), and pulmonary embolism (2.74% vs 0.75%, P = .031). The most common reasons for early aseptic revision were dislocation (41.5%), fracture (38.1%), and loosening (17.4%).ConclusionEarly aseptic revision THA is associated with significantly higher 90-day complication rates and 2-year rerevision rates compared with a control group of primary THA without revision. The most common reasons for acute early revision were dislocation, fracture, and mechanical loosening.Level of EvidenceLevel III.     

Revision Hip Arthroplasty Using a Modular,Cementless Femoral Stem: Long-Term Follow-Up

BackgroundAs the number of primary total hip arthroplasty (THA) cases increase, so does the demand for revision operations. However, long-term follow-up data for revision THA is lacking.MethodsA retrospective review was completed of patients who underwent revision THA at a single institution between January 2002 and October 2007 using a cementless modular stem. Patient demographic, clinical, and radiographic data was collected. Preoperative and postoperative patient-reported outcome scores were compared at a minimum of fourteen-year follow-up.ResultsEighty-four patients (89 hips) with a median age of 69 years (range, 28 to 88) at operation were included. Indications for revision included aseptic loosening (84.2%), infection (12.4%), and periprosthetic fracture (3.4%). Twenty-two hips sustained at least 1 complication: intraoperative fracture (7.9%), dislocation (6.7%), prosthetic joint infection (4.5%), deep venous thrombosis (3.4%), and late periprosthetic fracture (2.2%). There were no modular junction complications. Eight patients underwent reoperations; only three involved the stem. Thirty-eight patients (45%) were deceased prior to final follow-up without known reoperations. Twenty-seven patients (32%) were lost to follow-up. Twenty-one patients (23%) were alive at minimum fourteen-year follow-up. Complete patient-reported outcomes were available for nineteen patients (range, 14 to 18.5 years of follow-up). Significant improvement was seen in UCLA activity, VR-12 physical, hip disability and osteoarthritis outcome score, joint replacement., and Harris Hip score pain and function scores.ConclusionChallenges of long-term follow-up include patient migration, an unwillingness to travel for re-examination, medical comorbidities, advanced age, and death. The cementless modular revision stem demonstrated long-term clinical success and remains a safe and reliable option for complex revision operations.     

Survival Rate and Application Number of Total Hip Arthroplasty in Patients With Femoral Neck Fracture: An Analysis of Clinical Studies and National Arthroplasty Registers

BackgroundTotal hip arthroplasty (THA) is an increasingly popular treatment option for fractured neck of femur (NOF). The primary aim of this study is to systematically review all literature on primary THA and hemiarthroplasty (HA) after fractured NOF to calculate an overall revision rate. Furthermore, we wanted to compare primary THA implantations after fractured NOF between different countries in terms of THA number per inhabitant.MethodsAll clinical studies on THA and HA for femoral neck fractures between 1999 and 2019 were reviewed and evaluated with a special interest on revision rate. Revision rate was calculated as “revision per 100 component years.” THA registers were compared between different countries with respect to the number of primary implantations per inhabitant.ResultsTHA studies showed a mean revision rate of 11.8% after 10 years, which was lower than a 24.6% 10-year revision rate for HA. We identified 8 arthroplasty registers that revealed an annual average incidence of THA for fractured NOF of 9.7 per 100,000 inhabitants.ConclusionThis study showed that patients with THA were less likely to be revised at 10 years compared to HA. We found similar annual numbers of THAs for fractured NOF per inhabitant across countries. The results of this analysis can be used to rank present and future national THA numbers within an international context.     

Contemporary Total Hip and Total Knee Arthroplasty Results in Patients with Hemochromatosis

BackgroundHemochromatosis can result in metabolic bone pathology (due to excessive iron absorption) and degenerative joint disease, leading to total joint arthroplasties. The aim of this study is to analyze the survivorship, complications, radiographic results, and clinical outcomes of patients with hemochromatosis who received either a total hip arthroplasty (THA) or a total knee arthroplasty (TKA).MethodsWe identified 34 lower extremity arthroplasties in 29 patients with hemochromatosis performed between 2000 and 2016. There were 17 primary THAs in 15 patients and 17 primary TKAs in 14 patients. Mean age at arthroplasty was 63 years with 76% being male. The mean body mass index was 28 kg/m². Mean follow-up was 5 years.ResultsThe survivorship free from any revision for THAs was 94% at 10 years. One patient was revised for aseptic loosening of the femoral stem at 6 months. In THA patients, no infections, no other complications, and no radiographic evidence of aseptic loosening were identified. Harris Hip Scores improved from a mean of 55 preoperatively to 94 postoperatively (P < .001). The survivorship free from any revision for TKAs was 100% at 10 years. Two patients (12%) developed acquired idiopathic stiffness postoperatively; no infections were identified. There was no radiographic evidence of aseptic loosening in any TKA. Knee Society Scores improved from a mean of 61 preoperatively to 94 postoperatively (P < .001).ConclusionThis study found excellent survivorship, significant improvements in clinical outcomes, and a very low complication profile for both THA and TKA in patients with hemochromatosis.     

Instability After All-Cause Acetabular-Only Revision Total Hip Arthroplasty Remains a Clinical Problem

BackgroundThe purpose of this study is to (1) evaluate the rate of instability and reoperation after acetabular component–only revision, (2) compare instability rates across various head sizes, and (3) determine patient factors correlating with postoperative instability.MethodsWe retrospectively reviewed all isolated acetabular component revisions (n = 200) at our institution between 2007 and 2017. Patients with less than one-year follow-up were excluded. Patients were subdivided into 4 head size groups: (1) 32 mm or less, (2) 36 mm or more, (3) dual mobility, and (4) constrained liners. Factors including the body mass index, cup position, prior revision(s), and subsequent reoperation were compared across groups.Results189 patients (200 hips) met the inclusion criteria. The overall rate of instability was 12% (n = 24), and 37 (18.5%) cases underwent subsequent revision, including 11 cases for recurrent instability. There was no significant difference in postoperative dislocation or reoperation for instability across the various groups. The use of a constrained liner trended toward the highest rate of postoperative instability (36.4%, P = .090). History of preoperative instability was a significant risk factor for postoperative instability with or without history of prior revision (P = .011 and P = .001, respectively).ConclusionContemporary isolated acetabular revision is still associated with significant rates of instability. Surprisingly, the head size was not a predictive factor for postoperative dislocation or reoperation, but a prior history of instability was associated with postoperative instability. Patients revised to a constrained liner experienced highest rates of failure and remain an unsolved clinical problem.     

Outcome and Risk Factors Associated with Failures of Isolated Bearing Exchange for Osteolysis in Well-Fixed Cementless Total Hip Arthroplasty

BackgroundIt is often challenging to decide whether to revise only the bearing or femoral acetabular component in the setting of progressive osteolysis without component loosening in revision total hip arthroplasty (THA). In this study, we aimed to (1) compare the survivorship of isolated bearing exchange and single/both component revision for patients with periprosthetic osteolysis without component loosening, and (2) identify potential risk factors associated with failures of isolated bearing exchange.MethodsA total of 228 consecutive cases of revision THA for progressive osteolysis without component loosening was evaluated in 2 groups: (1) 124 component revision and (2) 104 isolated bearing exchange. The primary outcome was survival, with failure defined as repeat revision or reoperation for any reason. Patient risk factors, such as demographics and medical comorbidities, were also analyzed.ResultsThere was no significant difference in survivorship between the component revision group and the bearing exchange group at 10 years (85% vs 82%; P = .89). There was no progression of osteolysis on radiographs at last follow-up for patients with isolated bearing change. Univariate regression modeling demonstrated that renal disease was associated with failure of isolated bearing exchange after revision THA.ConclusionThis study demonstrated that isolated bearing exchange is associated with similar outcomes compared with component revision for aseptic osteolysis without loosening, demonstrating that isolated bearing exchange is a viable option for selected patients with osteolysis in the setting of well-fixed THA components. This provides clinically useful information for surgeons in the surgical treatment of THA patients with wear and osteolysis without component loosening.     

Risk Factors for Dislocation and Re-revision After First-Time Revision Total Hip Arthroplasty due to Recurrent Dislocation – A Study From the Danish Hip Arthroplasty Register

BackgroundPersistent instability after hip revision is a serious problem. Our aim was to analyze surgical and patient-related risk factors for both a new dislocation and re-revision after first-time hip revision due to dislocation.MethodsWe included patients with a primary THA due to osteoarthritis and a first-time revision due to dislocation registered in the Danish Hip Arthroplasty Register (DHR) from 1996 to 2016. We identified dislocations in the Danish National Patient Register and re-revisions in the DHR. Risk factors were analyzed by a multivariable regression analysis adjusting for the competing risk of death. Results are presented as subdistribution hazard ratios (sHR).ResultsWe identified 1678 first-time revisions due to dislocation. Of these, 22.4% had a new dislocation. 19.8% were re-revised for any reason. With new dislocations treated by closed reduction as the endpoint, the sHR was 0.36 (95% CI, 0.27-0.48) for those who had a constrained liner (CL) during revision and 0.21 (0.08-0.58) for dual mobility cups (DMC), thereby lowering the risk of dislocation compared to regular liners. Changing only the head/liner increased the risk of dislocation (sHR = 2.65; 2.05-3.42) compared to full cup revisions. The protective effect of CLs and DMCs on dislocations vanished when re-revisions became the endpoint. The head/liner exchange was still found inferior compared to cup revision (sHR = 1.73; 1.34-2.23).ConclusionPatients revised with DMCs and CLs were associated with a lower risk of dislocation after a first-time revision but not re-revision, whereas only changing the head/liner was associated with a higher risk of dislocation and re-revision of any cause compared to cup revision.