The Accuracy of Digital Templating in Uncemented Total Hip Arthroplasty

We analyzed the reproducibility and reliability of computer templating in primary uncemented total hip arthroplasties as compared to standard onlay templating techniques with hardcopy radiographs from a digital source. Digital templating showed good intraobserver and interoberserver reliability with intraclass correlation coefficient values greater than 0.7. Using computer templating, prediction of sizing to within 1 size was 85% accurate for femoral stem sizing and 80% accurate for acetabular sizing. Using onlay templating, prediction of sizing to within 1 size was 85% accurate for femoral sizing and 60% accurate for acetabular sizing. We conclude that the introduction of digital templating has significant benefits in preoperative planning for total hip arthroplasty over onlay templating.     

Fracture of Fully Coated Echelon Femoral Stems in Revision Total Hip Arthroplasty

Three cases of fractured uncemented, fully porous Echelon femoral stems (Smith & Nephew, Memphis, Tenn) are examined. Fracture of these components, an uncommon complication of revision hip surgery, is thought to result from cantilever bending after distal bony ingrowth. The stems in these cases fractured at 11, 22, and 28 months after revision surgery. Risk factors include increased body weight, excessive activity, an undersized stem, varus alignment, inadequate proximal femoral bone stock, and metallurgic defects. Extraction can be difficult and is often accomplished with the use of multiple trephines or via tamping through a distal cortical window.     

A Systematic Review and Meta-Analysis of Non-database Comparative Studies on Cemented Versus Uncemented Femoral Stems in Primary Elective Total Hip Arthroplasty

BackgroundCemented and uncemented femoral stems have shown excellent survivorship and outcomes in primary total hip arthroplasty (THA). Cementless stems have become increasingly common in the United States; however, multiple large database studies have suggested that elderly patients may have fewer complications with a cemented stem. As conclusions from large databases may be limited due to variations in data collection, this study investigated femoral stem survivorship and complication rates based on cement status in non-database studies.MethodsPreferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were utilized to identify articles for inclusion up until June 2021. Included articles directly compared outcomes and complications between patients undergoing primary THA without femoral stem cementing to those with cementing. Studies were excluded if they utilized large databases or consisted of patients with a preoperative diagnosis of trauma.ResultsOf the 1700 studies, 309 were selected for abstract review and nineteen for full-text review. A total of seven studies were selected. Meta-analyses indicated substantial heterogeneity between studies. There were no differences in revision rates (cementless: 5.53% vs. cemented 8.91%, P = .543), infection rates (cementless: 0.60% vs. cemented: 0.90%, P = .692), or periprosthetic fracture rates (cementless: 0.52% vs. cemented: 0.51%, P = .973) between groups.ConclusionThere is scarce literature comparing outcomes and complications between cemented and cementless femoral stems in primary elective THA without utilizing a database methodology. In our study, there were no differences in complications detected on meta-analyses. Given previous findings in database studies, additional high-quality cohort studies are required to determine if selected patients may benefit from a cemented femoral stem.     

A Comparative Study Between Uncemented and Hybrid Total Hip Arthroplasty in Octogenarians

Background

The aim of this prospective cohort study is to evaluate the outcome of octogenarian patients undergoing uncemented total hip arthroplasty (THA) with a control group of similarly aged patients undergoing hybrid THA with a minimum 5-year follow-up.

A Role for Modern Primary Cementless Femoral Stems in Revision Hip Arthroplasty

BackgroundIn revision total hip arthroplasty (THA) cases with preserved femoral metaphyseal bone, tapered proximally porous-coated “primary” femoral stems may be an option. The objective of this study was to compare outcomes of patients with Paprosky I or II femoral bone loss undergoing revision THA with either a primary metaphyseal-engaging cementless stem or a revision diaphyseal-engaging stem.MethodsThis was a retrospective analysis of 70 patients with Paprosky I or II femoral bone loss who underwent femoral revision. 35 patients who were revised using a primary cementless femoral stem were compared with 35 patients who underwent femoral revision using a revision diaphyseal-engaging stem. The groups were similar regarding age, gender, body mass index, and American Society of Anesthesiologists. Clinical and radiographic outcomes and complications were compared over an average follow-up of 2.9 years (SD 1.4).ResultsRevision THA was most commonly performed for periprosthetic joint infection (N = 27, 38.6%). The groups were similar with regards to Paprosky femoral classification (P = .56), length of stay (P = .68), discharge disposition (P = .461), operative time (P = .20), and complications (P = .164). There were no significant differences between primary and revision femoral stem subsidence (0.12 vs. 0.75 mm, P = .18), leg length discrepancy (2.3 vs. 4.05 mm, P = .37), and Hip Disability and Osteoarthritis Outcome Score Jr (73.1 [SD 21.1] vs. 62.8 [SD 21.7], P = .088). No patient underwent additional revision surgery involving the femoral component.ConclusionUse of modern primary cementless femoral stems is a viable option for revision hip arthroplasty in the setting of preserved proximal femoral metaphyseal bone. Outcomes are not inferior to those of revision stems and offer potential benefits.     

Results With the Cementless Spotorno Stem in Total Hip Arthroplasty

Increasingly young and active patients are undergoing total hip arthroplasty, making hip prosthesis survival rates an important issue. Cementless total hip arthroplasty provides better prosthesis longevity than does cemented hip arthroplasty, especially in younger patients. Because there is growing support in the literature for tapered geometry in cementless femoral components, we evaluated short-term results for total hip arthroplasty using Cementless Spotorno (CLS) titanium stems. We performed 100 consecutive primary cementless total hip arthroplasties in 87 patients during a 9-year period using CLS stems. Outcome was assessed in terms of survival rate and Harris Hip Score. The stem survival rate was 99%, and the average Harris Hip Score improved from 41 before surgery to 92 at a mean point of 5 years after surgery. Only 1 hip underwent stem revision for a periprosthetic shaft femur fracture caused by high-velocity trauma from a vehicle accident that occurred 6 months after the original surgery. The CLS stems have an excellent survival rate in the short term, especially in younger patients, but long-term studies are required to provide a fuller picture.     

Bicortical Contact Predicts Subsidence of Modular Tapered Stems in Revision Total Hip Arthroplasty

BackgroundWe describe the intraoperative parameters that affect stem subsidence rates in tapered modular femoral stems for revision total hip arthroplasty (THA). We also determine the effect of the stem bicortical contact on subsidence rates and whether there is a minimum threshold bicortical contact that must be achieved to avoid the complication of subsidence.MethodsThis is a retrospective cohort study consisting of 109 hips in 105 patients (53 males and 52 females) at a minimum of 2 years of follow-up. All revisions were carried out for Paprosky type 3A and 3B femoral deficits. Clinical outcomes included the indication for revision, aseptic re-revision surgery, specifications of the stem inserted, and specifications of the femoral head and acetabular components implanted. Radiographic outcome measures included subsidence (mm) and bicortical contact (mm).ResultsUsing multivariate regression analysis, 3 parameters were associated with an increased rate of stem subsidence. A reduced bicortical contact distance (P < .001) and a stem length of ≤155 mm (P < .001) were both associated with higher subsidence rates. We also demonstrated a novel threshold of 20-mm bicortical contact which must be achieved to significantly reduce subsidence rates in these modular femoral stems for revision THA.ConclusionSubsidence rates of modular tapered femoral stems for revision THA can be significantly reduced by increasing the initial bicortical contact of the stem within the diaphysis and the overall length of the femoral stem >155 mm. We describe a minimum threshold bicortical contact distance of 20 mm that should ideally be exceeded to significantly reduce the risk of stem subsidence within the femoral canal.     

Revision Total Hip Arthroplasty With a Modular Cementless Femoral Stem

We retrospectively reviewed 123 patients who underwent cementless THA with modular femoral stem designs for revision THA or conversion of failed ORIF and found 75 patients available for analysis. The Harris Hip Score (HHS) improved from 52 ± 14 to 86 ± 11 (P < 0.001). The femoral stem was re-revised in eight patients (11%). The mean time to re-revision was 1.1 years (0.13–2.54). Reasons for re-revision included infection (n = 5, 7%), aseptic loosening (n = 2, 3%) and significant pain (n = 1, 1%). There were no failures of the modular junctions. PC stems had an increased rate of intraoperative fractures (PC 28% vs. STS 9%, P = 0.04). Modular cementless femoral stems provide acceptable mid-term results in revision THA.     

Outcomes of Long Tapered Hydroxyapatite-Coated Stems in Revision Total Hip Arthroplasty

The purpose of this study was to evaluate the outcome of femoral component revisions using a long tapered HA coated femoral revision stem. Between 2001 and 2008, 55 femoral component revisions were performed using this stem. Forty-one patients were available for follow up evaluation at average of 59 months. The clinical results were evaluated using the HHS and serial radiographs were evaluated for loosening. The mean HHS was 71 (range 22–100). Three hips required revision of KAR stem (1 aseptic loosening, 1 infection, 1 limb length discrepancy). Only one prosthesis demonstrated radiographic evidence of subsidence. Our study suggests that long tapered HA coated revision femoral components can provide stable fixation and in-growth in cases where there is good proximal femoral bone stock and favorable canal geometry.     

Component Asymmetry in Bilateral Cementless Total Hip Arthroplasty

BackgroundThis study investigated the results of component asymmetry (CA) in bilateral cementless total hip arthroplasty (THA).MethodsThis study included 300 patients, who underwent bilateral cementless THA between April 2000 and December 2017. They were divided into the component symmetry (CS) and CA groups; CA group was sub-classified into acetabular component asymmetry (ACA) and femoral component asymmetry (FCA). Radiologic and clinical outcomes of the CA group were compared with those of the CS group.ResultsThe incidence of CA was 25.7% (77/300 patients), including 55 patients with ACA, 34 patients with FCA, and 12 with both components asymmetric. The mean time interval between operations in the CA group was significantly longer than that in the CS group (p < 0.001). The mean differences in horizontal and vertical distances from teardrop to the center of rotation of the acetabular component between both hips in the ACA group were significantly larger than those in the CS group (p = 0.033 and p < 0.001, respectively). The mean femoral component alignment angle difference between both hips was significantly larger in the FCA group than in the CS group (p < 0.001). The mean Harris Hip Score at last follow-up of the CA group was similar to that of the CS group.ConclusionsCA in patients undergoing bilateral cementless THA was not rare, especially with a longer time interval between operations. Regardless of CA, when stable fixation of the components was achieved, satisfactory radiologic and clinical outcomes were obtained.     

Standard Versus Custom-Made Acetabular Implants in Revision Total Hip Arthroplasty

BackgroundToday, various options are used for the reconstruction of acetabular bone loss in revision total hip arthroplasty (RTHA). The aim of the study was to compare the outcomes of using standard acetabular implants (SAIs) and custom-made acetabular implants (CMAIs) in RTHA in cases with extensive acetabular bone loss.MethodsThis was a comparative analysis of the results of 106 operations of RTHA performed during the period from January 2013 to December 2019. In 61 cases (57.5%), CMAIs were used. In 45 cases (42.5%), SAIs were implanted.ResultsThe incidence of aseptic loosening of the acetabular component after RTHA in uncontained loss of bone stock of the acetabulum (type III-IV as per the Gross and Saleh classification) using the CMAI was less than that using the SAI (2.4% and 10.0%, respectively). The most significant differences in aseptic loosening rates were noted after implantation of the CMAI and SAI in pelvic discontinuity with uncontained bone defect (0% and 60.0%, respectively; P < .001).ConclusionThe ideal indications for the use of the CMAI are uncontained defects and pelvic discontinuity with uncontained loss of bone stock (types III-V Gross and Saleh classification). Treatment of these defects with the SAI leads to a higher incidence of aseptic loosening requiring re-revisions. Further observation is required to assess the effectiveness of using the CMAI and SAI in the long-term follow-up period.     

High Offset Stems Are Protective of Dislocation in High-Risk Total Hip Arthroplasty

BackgroundSpinal stiffness has been shown to increase risk of dislocation due to impingement and instability. Increasing anteversion of the acetabular component has been suggested to prevent dislocation, but little has been discussed in terms of femoral or global offset restoration. The purpose of this study is to quantify dislocation rates after primary THA using standard versus high-offset femoral components and to determine how differences in offset affect impingement-free range of motion in a stiff spine cohort using a novel impingement model.MethodsA total of 12,365 patients undergoing THA from 2016 to 2018 were retrospectively reviewed to determine dislocation rates and utilization of standard- versus high-offset stems. For 50 consecutive patients with spinal stiffness, a CT-based computer software impingement modeling system assessed bony or prosthetic impingement during simulated range of motion. The model was run 5 times for each patient with varying offsets. Range of motion was simulated in each scenario to determine the degree at which impingement occurred.ResultsThere were 51 dislocations for a 0.41% dislocation rate. Total utilization of high-offset stems in the entire cohort was 49%. Of those patients who sustained a dislocation, 49 (96%) utilized a standard-offset stem. The impingement modeling demonstrated 5 degrees of added range of motion until impingement for every 1 mm offset increase.ConclusionIn the impingement model, high-offset stems facilitated greater ROM before bony impingement and resulted in lower dislocation rates. In the setting of high-risk THA due to spinal stiffness, surgeons should consider the use of high-offset stems and pay attention to offset restoration.     

Advantage of the Uncemented Total Hip System with Three Spiked Socket

Atotal hip arthroplasty was performed on 112 joints of 110 patients from November 1983 to January 1998 using three different types of uncemented total hip systems with a three spiked socket. The clinical results of 87 joints of 85 patients, followed up 5 years or more after operation, were evaluated with the comparison among the three different types (original type [JIAT] in 6, type Y in 24, and type Y2 in 57). In 73 of the 87 patients, the age at the time of the operation was more than 60. The preoperative diagnosis was osteoarthritis with acetabular hypoplasia in 61, rapidly destructive coxarthrosis in 17, and so on. We have been receiving excellent clinical results of patients who were implanted with type Y2 compared with the other types. There was no different clinical results between patients who were less than 60 and patients who were over 60. Injuries of neurovascular bundle relating to the penetration of the tip of the spike, which was a concern in this type of socket, were not encountered. The type Y2 uncemented total hip system shows an indication of being successful even if the patients have poor bone stock in acetabulum or are elderly.     

Perioperative Fractures in Cementless Total Hip Arthroplasty Using the Direct Anterior Minimally Invasive Approach: Reduced Risk With Short Stems

Background

The direct minimally invasive anterior approach (DMIAA) and the use of uncemented stems demonstrated an increase in intraoperative fractures in recent literature. Whether the different design of the stems additionally influences the incidence of perioperative local complications, was the goal of this study.

Poor Short Term Outcome with a Metal-On-Metal Total Hip Arthroplasty

Metal-on-metal (MoM) bearings for total hip arthroplasty (THA) have come under scrutiny with reports of high failure rates. Clinical outcome studies with several commercially available MoM THA bearings remain unreported. We evaluated 78 consecutive MoM THAs from a single manufacturer in 68 patients. Sixty-six received cobalt–chrome (CoCr) monoblock and 12 received modular titanium acetabular cups with internal CoCr liners. Femoral components were titanium with modular necks. At average 2.1 years postoperatively, 12 THAs (15.4%) demonstrated aseptic failure (10 revisions, 2 revision recommended). All revised hips demonstrated capsular necrosis with positive histology reaction for aseptic lymphocytic vasculitis-associated lesions/adverse local tissue reactions. Prosthetic instability following revision surgery was relatively common. Female gender was a strong risk factor for failure, though smaller cups were not. Both monoblock and modular components fared poorly. Corrosion was frequently observed around the proximal and distal end of the modular femoral necks.     

Independent Risk Factors for Transfusion in Contemporary Revision Total Hip Arthroplasty

BackgroundThe incidence of transfusion in contemporary revision total hip arthroplasty (THA) remains high despite recent advances in blood management, including the use of tranexamic acid. The purpose of this prospective investigation was to determine independent risk factors for transfusion in revision THA.MethodsSix centers prospectively collected data on 175 revision THAs. A multivariable logistic analysis was performed to determine independent risk factors for transfusion. Revisions were categorized into subgroups for analysis, including femur-only, acetabulum-only, both-component, explantation with spacer, and second-stage reimplantation. Patients undergoing an isolated modular exchange were excluded.ResultsTwenty-nine patients required at least one unit of blood (16.6%). In the logistic model, significant risk factors for transfusion were lower preoperative hemoglobin, higher preoperative international normalized ratio (INR), and longer operative time (P < .01, P = .04, P = .05, respectively). For each preoperative 1g/dL decrease in hemoglobin, the chance of transfusion increased by 79%. For each 0.1-unit increase in the preoperative INR, transfusion chance increased by 158%. For each additional operative hour, the chance of transfusion increased by 74%. There were no differences in transfusion rates among categories of revision hip surgery (P = .23). No differences in demographic or surgical variables were found between revision types.ConclusionDespite the use of tranexamic acid, transfusions are commonly required in revision THA. Preoperative hemoglobin and INR optimization are recommended when medically feasible. Efforts should also be made to decrease operative time when technically possible.     

Total Hip Arthroplasty After Hip Arthroscopy Has Increased Complications and Revision Risk

BackgroundThere has been an increase in hip arthroscopy (HA) over the last decade. After HA, some patients may ultimately require a total hip arthroplasty (THA). However, there is a scarcity of research investigating the outcomes in patients undergoing THA with a history of ipsilateral HA.MethodsThe PearlDiver research program (www.pearldiverinc.com) was queried to capture all patients undergoing THA between 2015 and 2020. Propensity matching was performed to match patients undergoing THA with and without a history of ipsilateral THA. Rates of 30-day medical complications, 1-year surgical complications, and THA revision were compared using multivariate logistic regression. Kaplan-Meier analysis was conducted to estimate survival probabilities of each of the groups with patients undergoing THA .ResultsAfter propensity matching, cohorts of 1940 patients undergoing THA without prior HA and 1940 patients undergoing a THA with prior HA were isolated for analysis. The mean time from HA to THA was 1127 days (standard deviation 858). Patients with a history of ipsilateral HA had an increased risk for dislocation (odds ratio [OR] 1.56, P = .03) and overall decreased implant survival within 4 years of undergoing THA (OR 1.53; P = .05). Furthermore, our data demonstrate the timing of previous HA to be associated with the risk of complications, as illustrated by the increased risk for dislocation (OR 1.75, P = .03), aseptic loosening (OR 2.18, P = .03), and revision surgery at 2 (OR 1.92, P = .02) and 4 years (OR 2.05, P = .01) in patients undergoing THA within 1 year of HA compared twitho patients undergoing THA more than 1 year after HA or with no previous history of HA.ConclusionPatients undergoing THA after HA are at an increased risk for surgical complications, as well as the need for revision surgery.