Cementless Total Hip Arthroplasty Research Articles

Effect of Total Hip Arthroplasty with Ceramic Acetabular Component on Clinical, Radiographic and Functional Parameters in Older Patients with Hip Osteoarthritis: Two-Year Follow-Up.

Background: Total hip arthroplasty (THA) is a widely used surgical procedure to reduce pain and improve function and quality of life in patients with hip disorders. The most common condition that leads to THA is osteoarthritis, with most surgeries being performed to treat severe osteoarthritis with pain and functional limitations. Despite the evident success of THA, the search for its improvement and better results, especially in the long term, continues, especially in older patients, for which there is still little scientific evidence. Objective: To evaluate the clinical, radiological, and functional aspects preoperatively and two years after THA with a ceramic acetabular component device in older patients with hip osteoarthritis. Methods: A retrospective cohort study was conducted to evaluate 65 older individuals who underwent THA of the hip with an acetabular component (MD® ceramic head with a ceramic acetabular insert) associated with the MD6® Phenom® femoral rod type, in Hospital of the Luz, São Paulo/SP, between 2018 and 2019. Anthropometric and clinical information about the operative procedure and two years follow-up were collected from the patients’ medical records. For the clinical-functional evaluation, the Harris Hip Score (HHS) questionnaire and hip movement goniometry were applied. For the radiographic parameters, the following were evaluated: the positioning of the acetabular component, the Zone of DeLee and the offset of the femoroacetabular component. Results: There was a higher prevalence of performing THA in males (53.8%). Preoperative and two-year postoperative radiographic parameters of surgical treatment for THA showed maintenance of the acetabular (p = 0.083) and femoral (p = 0.102) positioning angles and increased functionality (p < 0.001) and joint mobility of the hip (p = 0.001) with reduced pain after two years of THA. Complications related to dislocation, loosening, infection, and inadequate positioning of the implant were low, ranging from 1.5 to 3%. Conclusion: Older people who underwent cementless THA with an ceramic acetabular component device, in a two-year follow-up, showed effectiveness in improved clinical, radiological, and functional aspects.

Standard and special liner in primary hip arthroplasty : Current study and survey results from the German Arthroplasty Registry (EPRD)

Instability constitutes the main reason for revision hip arthroplasties. Modified polyethylene liners are designed to improve the stability of ahip replacement. In July 2022 The Bone & Joint Journal published astudy with data of the German Arthroplasty Registry (EPRD). The study investigated mechanical failure of standard and modified liner designs in primary, cementless total hip arthroplasty. Following the study, the EPRD conducted asurvey of German clinics to research the utilization of lipped liners in primary total hip replacement. The liner study included 151,096 primary, elective, cementless total hip arthroplasties. Data from November 2012 to November 2020 were obtained from the EPRD. Standard polyethylene liners were compared with lipped, angulated, offset and angulated/offset inlays. Cumulative incidences for endpoint revision due to mechanical complication were calculated with acompeting risk analysis. The influence of other variables was investigated with amultivariate Cox regression. In the following online survey, 237 out of 789 hospitals completed aform. In our analysis, only offset liners were, compared to standard liners, associated with areduced risk of mechanical failure in ashort to medium follow up. However, the resultant joint reaction force is increased with offset liners due to the lateralization of the hip center of rotation. Thus, the long-term performance of offset liners needs to be observed. Our survey indicated that lipped liners were implanted more often if the posterior approach was used. Moreover, lipped liners were mostly positioned with the elevated rim in the biomechanically less optimal posterior-superior quadrant. To improve stability it is suggested to position the elevated rim in the posterior-inferior quadrant.

A 10- to 12-year follow-up study of delta ceramic-on-ceramic total hip arthroplasty.

We previously reported five-to-seven-year results of total hip arthroplasty (THA) with the use of delta ceramic-on-ceramic (CoC) bearing. We conducted an extension study with a CT scan at a minimum of 10years after surgery. From March 2009 to March 2011, 273 patients (310 hips) received cementless THA with delta CoC bearing, porous-coated cup and hydroxyapatite-coated stem. In this extended study, 252 patients (144 men and 108 women) (288 hips) with a mean age of 49.7years (16-83) at surgery were followed for a mean of 10.4years (10-12) with CT scans in 133 hips (46.2%, 133/288). Clinical and radiographic evaluations were made at each follow-up and Kaplan-Meier survival analysis was performed with revision and reoperation as endpoints. There were no more ceramic fractures. Compared to mid-term results, the incidence of squeaking and RLLs increased to 3.1% (9/288) and 19.4% (56/288), respectively. The RLL progressed to focal osteolysis in 3 hips (5.4%, 3/56). No hip had detectable wear or prosthetic loosening. Two hips were reoperated due to periprosthetic joint infection and periprosthetic femoral fracture in each. The survivorship decreased to 98.3% (96.7-99.9%) at 12years. During the extended follow-up, no additional ceramic fracture occurred, and the incidence of squeak increased by 0.7%. The long-term survivorship of Delta CoC THA was encouraging. However, focal osteolysis occurred around the hydroxyapatite-coated stem in 1% (3/288). II (Prospective cohort study).

Biomechanical evaluation of the impact of collared cementless total hip arthroplasty stems on implant subsidence: a cadaveric study in German Shepherd.

With the increasing use of cementless total hip arthroplasty (THA), stem subsidence has emerged as one of the primary complications. Although electron beam melting (EBM)-manufactured stems have been demonstrated to prevent subsidence, there has been limited investigation into the comparative biomechanical impact of collarless and collared EBM cementless stems on stem subsidence in veterinary medicine. This study aimed to compare the stem implant resistance and failure mechanical properties between collarless and collared EBM-manufactured stems. Seven pairs of femurs were harvested from canine cadavers. In each pair of femurs, the left femur was implanted with a collarless, and the right femur with a same-sized collared cementless stem. Specimen constructs were mounted to the loading frame of a testing machine and load was transferred to the femoral stem parallel to the longitudinal axis of the femur until the stem subsided 5 mm. Load and stem displacement data acquired during the tests were used to generate load-displacement curves and obtain stiffness, yield, and failure data for each specimen construct. Yield and failure energies were calculated as the areas under the load-displacement curves to the respective points. The effects of implant type and load during subsidence were analyzed using paired t-tests. The yield and failure loads for the collared stems were approximately 40% greater than for the collarless stems (156.39 ± 43.63 kgf vs. 112.01 ± 59.83 kgf, P<0.05). This study supported the advantages of collared EBM stems, including subsidence prevention and better initial stability for early osteointegration.

Long term results of total hip arthroplasty with cemented and cementless tapered femoral component.

Excellent midterm results for total hip arthroplasties (THA) with cementless, tapered porous Taperloc® femoral stems have been reported. Reports regarding such cemented stems, however, are lacking. To evaluate the long-term outcomes of both cemented and cementless THAs with the Taperloc femoral component. The medical records of 71 patients (76 hips), operated on between January 1991 and December 2003, who had a minimum follow-up of 10 years were available for analysis. Functional analysis was performed with the Harris hip score (HHS) questionnaire and the numerical analogue scale (NAS). Radiographic analysis was performed for subsidence, radiolucent lines and osteolysis. The cohort was comprised of 47 female and 24 male patients, with a mean age of 59.7±12.4 years. The mean follow-up was 17.8±4.4 years. 52.6% of THAs analyzed were cementless and 47.4% were cemented. Post-operative radiographs were available for 57 surgeries. Subsidence, hypertrophic ossification, radiolucent lines and osteolysis were noted in 4 (7%), 2 (2.6%), 14 (18.4%) and 11 (14.5%) hips respectively. The average HHS score at a mean follow-up of 20.1±3.9 years was 62.1 (±27.7) and the NAS score was 4.6 (±3.6). During the study period, five revision surgeries were performed due to stem-related problems, one of which was for aseptic loosening. Our long-term experience with the Taperloc stem, both cemented and cementless, demonstrates good outcomes, with low rates of failure. This makes this prosthesis an attractive option for THAs. IV.

Zurich Mini Cementless Total Hip Arthroplasty in 42 Small Breed Dogs and 8 Cats: Surgical Technique and Outcomes

AbstractThis report aims to describe implant characteristics and procedure for implantation, and comment on and report the clinical outcomes in small dogs and cats using the new Zurich mini cementless total hip system. This study involved 8 cats and 42 dogs, with 3 cats and 6 dogs having bilateral total hip arthroplasties (THA). The mean body weight for cats was 6.5 kg, and the mean body weight for dogs was 9.2 kg. In the group of THAs in cats, capital physeal fracture was the reason for performing a THA in six cases (60%), hip dysplasia was the underlying reason in four cases (30%) and hip luxation in one case (10%). Among the 48 THAs in dogs, hip dysplasia was the underlying cause for performing THA in 27 cases (56%), avascular necrosis of the femoral head in 12 cases (25%), traumatic luxation with underlying hip dysplasia in 4 cases (8.5%), capital physeal fracture in 4 cases (8.5%), and traumatic femoral head fracture in 1 adult dog (2%). Seven postoperative complications were encountered, and all were solved without the need for explanting the prosthesis, except in one case because of the owner's decision. In conclusion, the Zurich mini cementless total hip system performed well in this study, with most dogs and cats having an excellent outcome and no patient being too small for the available implant sizes.

Effect of surgical approach on functional outcome and component positioning in total hip arthroplasty

Context: Total hip arthroplasty (THA) is commonly performed through a posterior or a direct lateral (Hardinge) approach, and each one has merits and demerits. Aims: The purpose of this study was to examine the difference between the lateral and posterior approaches with respect to functional outcome, component positioning, intraoperative blood loss, and patient satisfaction. Settings and Design: This is a prospective comparative study of short- to mid-term outcome of cementless THA using two approaches. Subjects and Methods: Seventy hips satisfying our inclusion criteria were selected, of which 21 hips operated by lateral approach in supine position were included in lateral approach group (LAG), and 49 hips operated by posterior approach in lateral position were included in posterior approach group (PAG). Functional assessment was performed 1 day before surgery, 1 year after surgery, and at the latest follow-up using Harris Hip score (HHS). Component positioning of acetabular cup and femoral stem was assessed in plain radiographs at the latest follow-up. Generic satisfaction questionnaire was used to measure satisfaction after THA at the latest follow-up. Radiographic measurements (cup inclination, cup version, and femoral stem tip position) were performed postoperatively using low-centered pelvic anteroposterior and cross-table lateral hip radiographs. Results: At an average of 3 years and 6 months of follow-up, the mean HHSs were 88.05 and 90.32, respectively, in LAG and PAG; the difference was not significant (P = 0.178). The average inclination of the cup in LAG was 37.9° and in PAG was 45.02° with a significant difference (P = 0.00027), both of which are in the normal range. The cups were significantly (P ≤ 0.0001) more anteverted in the PAG (average angle of 27.69° vs. 16.14°). The mean blood loss was significantly more in PAG (510 ml vs. 436.67 ml; P = 0.04). Majority of femoral stems in lateral approach had their tips directed posterior. Nineteen out of 21 LAG patients and 45 out of 49 PAG were very satisfied/satisfied with their outcomes after THA. Statistical Analysis Used: Data were collected using prestructured data forms and analyzed with unpaired Student's t-test with 95% confidence interval. Conclusions: There was no significant difference in functional outcome and patient satisfaction at short- to mid-term follow-up between both approaches. The cup anteversion was significantly more in PAG. For better conclusions, other factors (i.e. immediate postoperative pain, and long-term survival), combined anteversion and spinopelvic parameters, have to be included in the study with a larger sample size.

Acetabular Inclination as a Function of Hip Center of Rotation While Obtaining Inferior Screw Fixation: A Simulation Model

AbstractClinical success of cementless total hip arthroplasty is predicated on proper component position, restoration of biomechanics, and implantation of a mechanically stable construct. In the setting of acetabular bone loss, this target is more difficult to achieve, and elevation of the center of hip rotation may compromise the ability to obtain inferior screw fixation. We used the LifeMOD virtual human modeling simulation software (Smith &amp; Nephew, San Clemente, CA) to determine the relationship between cup inclination and center of rotation position while maintaining the ability to obtain screw fixation within the superior pubic ramus. This simulation demonstrated that for every 5 mm of hip center elevation, cup inclination increased by 5.67 degrees. Based on this data, we recommend the use of a porous acetabular component when the hip center is elevated. This acetabular reconstruction allows for cementation of a liner to address the vertical nature of the cup needed to obtain inferior screw fixation within the superior pubic ramus.

Single Wedge Femoral Stem Designs are Associated With a Higher Risk for Revision After Cementless Primary Total Hip Arthroplasty

BackgroundCementless total hip arthroplasty (THA) femoral stems are the most commonly selected prostheses in the United States. Optimal stem geometry remains controversial with excellent survivorship reported for many designs. We compared cause-specific stem revision of single-wedge versus double-wedge designs from a multicenter US cohort. MethodsData from an integrated healthcare network’s total joint replacement registry were used to conduct a cohort study. Primary elective cementless THAs were identified (2001 to 2018). Implant exposure groups were classified by design geometry using the system proposed by Khanuja et al. Type 1 single-wedge (n = 11,082) and type 2 double-wedge (n = 32,380) designs were compared, and other design types were excluded; the final study cohort comprised 43,462 THAs. Cause-specific multivariable Cox regressions were used to evaluate risk for revision due to infection or aseptic reasons, including loosening, instability, periprosthetic fracture, or other reasons. ResultsAfter adjustment for covariates, a higher aseptic revision risk was observed for type 1 when compared to type 2 designs (hazard ratio = 1.91, 95% confidence interval = 1.33-2.75). When looking at specific revision reasons, revision for aseptic loosening (hazard ratio = 3.46, 95% confidence interval = 2.24-5.34) was higher for type 1 versus type 2 designs. No differences were found for septic revision, instability, periprosthetic fracture, or revisions for other reasons. ConclusionsType 1 single-wedge designs were found to have a higher risk of revision due to aseptic loosening relative to type 2 double-wedge designs. Femoral stem geometry should be considered when selecting a cementless femoral implant. Level of EvidenceLevel III.

Hip Arthroplasty Femoral Stem Designs and Their Association With Early Postoperative Periprosthetic Femoral Fractures

BackgroundPeriprosthetic femoral fractures (PFFs) in total hip arthroplasty (THA), especially those in contact with the diaphyseal stem, carry high morbidity. This study evaluated how stem design influences the risk of early Vancouver B PFF or other PFF requiring operative intervention after THA. MethodsA multicenter, retrospective study of 3,433 primary cementless THAs performed from 2014 to 2021 included 2,302 single-taper (micro M/L [n = 1,169]; M/L [n = 1,133]) and 1,131 double-taper (fit-and-fill [n = 420]; compaction-collared [n = 711]) stems. Mean follow-up was 2.2 years (range, 0.3 to 6.5 years). Primary outcomes were Vancouver B and surgically treated postoperative PFFs among differing femoral stems. Secondary outcomes included rates of intraoperative and postoperative Vancouver A and C PFFs. ResultsForty five postoperative PFFs (1.3%) occurred within 8.8 weeks (median), 25 of which were Vancouver B (0.7%) and 20 total PFFs that required operative intervention (0.6%). Compaction-collared stems had a decreased risk of Vancouver B (hazard ratio 0.18, 95% confidence interval: 0.03-0.97 P = .044) and any surgically treated PFF (hazard ratio 0.10, 95% confidence interval: 0.01-0.95; P = .037). Intraoperative PFFs were most common with fit-and-fill stems (3.6%, P < .001) and Vancouver A with compaction-collared stems (1.8%, P < .001). The cohort with PFF had a higher Charlson comorbidity index (P = .004), more women (P = .001), more Dorr A or C femora (P = .013), and more posterior or lateral surgical approaches compared to those without PFF (P ≤ .001). ConclusionAfter controlling for confounding variables, compaction-collared stems had a significantly lower risk of postoperative Vancouver B and PFF requiring operative treatment than single-taper and double-taper stems.

Величина шеечно-диафизарного угла ножки эндопротеза тазобедренного сустава как биомеханическая предпосылка развития асептической нестабильности вертлужного компонента (экспериментальное исследование)

Introduction Causes of aseptic loosening of THA components and improvement of the implants remain the subject of scientific discussions. The objective was to perform comparative analysis of the results of biomechanical modeling of cementless total hip arthroplasty using implants with different stem neck-shaft angles as a prerequisite of aseptic loosening of the acetabular component. Material and methods A biomechanical model of the pelvis and an implant with different stem neck-shaft angles was constructed based on computed tomography findings. Stresses and strains that the patient typically experienced under full weight-bearing on the operated lower limb were explored. Results The use of a stem neck-shaft angle of 125° provided the most favorable localization of the contact patch at the border of the acetabular component – the pelvic bone and lower values of equivalent stresses and contact pressure in comparison with more "valgus" femoral components (135° and 145°). Discussion The data obtained were fully consistent with the results of biomechanical studies by L. Quagliarella et al. (2006) who reported the substantial significance of the neck-shaft angle for on the parameters of contact pressure, since wear and debris-associated osteolysis decrease with a decreased neck-shaft angle. The use of stem neckshaft angles equal to 125° can be indicated for young patients with good bone quality and equal lower limb length. Unstable femoral cup can be caused by eccentric position of the contact spot at the border of the bone and the acetabular component and distribution of contact pressure and equivalent stresses inside the spot that are typical for artificial joints with stem neck-shaft angle of 145°. Conclusion The findings suggested that the value of stem neck-shaft angle was likely be considered a prerequisite for aseptic loosening of the acetabular component.

Case Series of Silver Oxide–Containing Hydroxyapatite Coating in Antibacterial Cementless Total Hip Arthroplasty: Clinical Results of 50 Cases at 5-Year Follow-Up

BackgroundProsthetic joint infection, which is caused by implant treatment, is a severe complication. Consequently, silver-containing hydroxyapatite (Ag-HA)-coated implants have been developed to prevent prosthetic joint infection by combining Ag with HA. The Ag-HA-coated total hip prosthesis, which combines the antibacterial activity of Ag and the osteoconductivity of HA, is the first antibacterial cementless total hip prosthesis worldwide. This study aimed to evaluate the short-term outcomes of total hip arthroplasty (THA) with Ag-HA-coated implants. MethodsOverall, 50 hips with various disabling hip diseases and postoperative infection risks that underwent a primary THA using an Ag-HA total hip prosthesis were enrolled. The patients included 37 women (41 hips) and 8 men (9 hips), and the mean age at the time of surgery was 77 years. The clinical outcomes and hip function before and at 5 years postoperatively were measured using the Japanese Orthopaedic Association hip score. Implant stability was assessed, and postoperative complications were also examined. ResultsThe Japanese Orthopaedic Association score increased in all cases and improved from 41 to 86 points after the THA (P < .001). Radiography revealed no implant failure. Dislocation and deep vein thrombosis also occurred in 1 case each. However, there were no adverse reactions associated with Ag, and argyria was not observed in any case. Additionally, none of the patients experienced infection following the surgery. ConclusionsSilver-containing hydroxyapatite–coated implants significantly enhanced patients’ daily activities without any adverse effects on the human body attributed to Ag, and they are expected to reduce postoperative infections.

Highly accurate acoustical prediction using support vector machine algorithm for post-operative subsidence after cementless total hip arthroplasty.

Acoustic analysis has recently been applied to cementless total hip arthroplasty (THA). The aim of this study was to develop a machine learning algorithm to predict post-operative subsidence with high accuracy. The acoustic parameters of the hammering sounds during a broaching procedure for 62 hips in 55 patients who underwent THAs with cementless taper-wedged stem were analysed. The patient's basic background such as age, sex, height, weight and body mass index, the femoral morphological parameters and the hammering sound characteristics of 24 features of normalised sound pressure (nSP) in 24 frequency ranges were applied to binary classification using a support vector machine using the following models with different features: model A, nSP only; model B, nSP + patients' basic background features; model C, nSP + patients' basic background features + femoral morphological parameters. In 62 hips with 310 hammering sounds, 12 hips (19.4%) showed ≥ 3mm of post-operative subsidence; hence, 60 hammering sounds were set as positive examples and 250 hammering sounds were set as negative examples. The AUC was very high in all models. The accuracy (AUC/sensitivity/specificity/positive predictive value/negative predictive value/accuracy rate) of each model was as follows: model A, 0.963/0.656/0.996/0.980/0.925/0.934; model B, 0.9866/0.675/1.000/1.000/0.928/0.937 and model C, 0.998/0.750/1.000/1.000/0.950/0.957. In this study, we developed a high-accuracy machine learning algorithm for post-operative subsidence using acoustic parameters and additional pre-operative features. Our results represent a step toward the realisation of acoustic monitoring to avoid the complication in cementless THA.

Minimum 30-Year Results of Bilaterally Implanted Cemented and Cementless Total Hip Arthroplasty in Patients Younger Than 50 Years

BackgroundThe rate of failure of cemented and cementless total hip arthroplasty (THA) in younger patients is higher than that in elderly patients. The purpose of this study is to document the long-term clinical results of THA with the so-called third-generation cementing and the results of second-generation cementless THA in patients <50 years of age. MethodsThis study included 106 patients who had had bilateral THA with a cemented stem in one hip and a cementless stem in the other. There were 78 men and 28 women. Their mean age was 47 years (range, 21-49). The average follow-up duration was 31 years (range, 30-32.5). ResultsThere were similar mean Harris Hip Scores (90 versus 91 points) between the groups at the final follow-up. Forty-six acetabular components (43%) in the cemented group and 48 acetabular components (45%) in the cementless group were revised. Five femoral components (5%) in the cemented group and 4 femoral components (4%) in the cementless group were revised. Survivorship of the acetabular component at 30.8 years was similar in both groups (57% in the cemented group versus 55% in the cementless group). Survivorship of the femoral component at 30.8 years was also similar in both groups (95% in the cemented group versus 96% in the cementless group). ConclusionLong-term fixation of the cemented or cementless femoral stem was outstanding. There was a high rate of the acetabular component revision due to conventional polyethylene wear and periacetabular osteolysis in both hybrid and fully cementless THA groups.

A case of staged revision cementless Total Hip Arthroplasty following post traumatic periprosthetic Vancouver type B fracture after hemiarthroplasty

The overall incidence of different types of periprosthetic fractures is on the rise constantly due to the increasing volume of primary joint arthroplasties and revision arthroplasties. Skills pertaining to advanced complex trauma and arthroplasty are necessary to manage these injuries. Inspite of various algorithms and classifications available regarding management of these injuries, it is necessary for the treating surgeon to understand that the treatment of periprosthetic fractures needs to be individualised optimal for that particular patient. We present our experience in a case of post traumatic periprosthetic Vancouver type B fracture after hemiarthroplasty treated with staged revision cementless long stem Total Hip Arthroplasty(THA).

Low-Molecular-Weight Heparins (LMWH) and Synthetic Factor X Inhibitors Can Impair the Osseointegration Process of a Titanium Implant in an Interventional Animal Study.

Background and objectives: Cementless total hip arthroplasty is a common surgical procedure and perioperative thromboprophylaxis is used to prevent deep vein thrombosis or pulmonary embolism. Osseointegration is important for long-term implant survival, and there is no research on the effect of different thromboprophylaxis agents on the process of osseointegration. Materials and Methods: Seventy rats were allocated as follows: Group I (control group), Group II (enoxaparin), Group III (nadroparin), and Group IV (fondaparinux). Ovariectomy was performed on all subjects, followed by the introduction of an intramedullary titanium implant into the femur. Thromboprophylaxis was administered accordingly to each treatment group for 35 days postoperatively. Results: Group I had statistically significantly lower anti-Xa levels compared to treatment groups. Micro-CT analysis showed that nadroparin had lower values compared to control in bone volume (0.12 vs. 0.21, p = 0.01) and percent bone volume (1.46 vs. 1.93, p = 0.047). The pull-out test showed statistically significant differences between the control group (8.81 N) compared to enoxaparin, nadroparin, and fondaparinux groups (4.53 N, 4 N and 4.07 N, respectively). Nadroparin had a lower histological cortical bone tissue and a higher width of fibrous tissue (27.49 μm and 86.9 μm) at the peri-implant area, compared to control (43.2 μm and 39.2 μm), enoxaparin (39.6 μm and 24 μm), and fondaparinux (36.2 μm and 32.7 μm). Conclusions: Short-term administration of enoxaparin, nadroparin, and fondaparinux can reduce the osseointegration of titanium implants, with nadroparin having the most negative effect. These results show that enoxaparin and fondaparinux are preferred to be administered due to a lesser negative impact on the initial implant fixation.

Two-stage revision for periprosthetic joint infection in cemented total hip arthroplasty: an increased risk for failure?

BackgroundThe impact of the prior fixation mode on the treatment outcome of chronic periprosthetic joint infection (PJI) of the hip is unclear. Removal of cemented total hip arthroplasty (THA) is particularly challenging and residual cement might be associated with reinfection. This study seeks to compare the results of two-stage revision for PJI in cemented and cementless THA.MethodsWe reviewed 143 consecutive patients undergoing two-stage revision THA for PJI between 2013 and 2018. Thirty-six patients with a fully cemented (n = 6), hybrid femur (n = 26) or hybrid acetabulum (n = 4) THA (cemented group) were matched 1:2 with a cohort of 72 patients who underwent removal of a cementless THA (cementless group). Groups were matched by sex, age, number of prior surgeries and history of infection treatment. Outcomes included microbiological results, interim re-debridement, reinfection, all-cause revision, and modified Harris hip scores (mHHS). Minimum follow-up was 2 years.ResultsCompared with PJI in cementless THA, patients undergoing removal of cemented THA had increasingly severe femoral bone loss (p = 0.004). Patients in the cemented group had an increased risk for positive cultures during second-stage reimplantation (22% compared to 8%, p = 0.043), higher rates of reinfection (22% compared to 7%, p = 0.021) and all-cause revision (31% compared to 14%, p = 0.039) compared to patients undergoing two-stage revision of cementless THA. Periprosthetic femoral fractures were more frequent in the group of patients with prior cementation (p = .004). Mean mHHS had been 37.5 in the cemented group and 39.1 in the cementless group, and these scores improved significantly in both groups (p < 0.01).ConclusionThis study shows that chronic infection in cemented THA might be associated with increased bone loss, higher rates of reinfection and all-cause revision following two-stage revision. This should be useful to clinicians counselling patients with hip PJI and can guide treatment and estimated outcomes.

Periprosthetic Femoral Fractures in Cementless Short Versus Straight Stem Total Hip Arthroplasty: A Propensity Score Matched Analysis

BackgroundRecent studies indicate a decreased risk of periprosthetic femoral fractures (PFFs) in cementless total hip arthroplasty (THA) for short compared to straight stems. However, the results are still inconclusive. Therefore, we retrospectively investigated the rate of PFFs within the first year between cementless short and straight stem THA. MethodsA 1:1 propensity score matching of 3,053 THAs was performed. Two groups including 1,147 short stem THAs implanted through a minimally invasive antero-lateral approach and 1,147 straight stem THAs implanted through a transgluteal Hardinge approach were matched. The rates of PFFs and fracture patterns were compared between both stem types. Risk factors for PFFs were analyzed by multivariate regression analyses. ResultsThe overall rate of PFFs was 1.7% in short stem THA and 3.2% in straight stem THA (P = .015). Postoperatively detected Vancouver A fractures occurred significantly more often in straight stem THA (P = .002), while the occurrence Vancouver B fractures did not differ significantly (P = .563). The risk of PFFs was significantly increased for women in straight stem THA (Odds ratio (OR) 2.620; Confidence Interval (CI) 1.172-5.856; P = .019). Increasing age showed a significantly increased odds ratio in short stem (OR 1.103; CI 1.041-1.169, P < .001) and straight stem THA (OR 1.057; CI 1.014-1.101, P = .008). ConclusionShort stem THA reduces Vancouver Type A PFFs in the trochanteric region compared to straight stem THA, while Vancouver Type B fractures are comparable. Increasing age is a significant risk factor for both stem types, while the risk for PFFs in women was only significantly increased in the straight stem group.

Comparisons of Different Bearing Surfaces in Cementless Total Hip Arthroplasty: A Systematic Review and Bayesian Network Analysis

BackgroundWe aimed to make comparisons of different bearing surfaces in patients after cementless total hip arthroplasty. MethodsThe network meta-analysis was guided by the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guideline. The primary outcomes were implant survival and Harris hip score (HHS). Secondary outcomes included linear wear rates and serum level of metal ions. Subgroup analyses were performed by: (1) classifying head sizes as small and large; (2) femoral heads as ceramic and metal; and (3) liners as metal, ceramic, polyethylene, highly cross-linked polyethylene (HXP), or vitamin E-infused highly cross-linked polyethylene (HXPE). A total of 64 eligible RCTs with different bearings were assessed. Overall inconsistency and heterogeneity were acceptable. ResultsIn the 10 years follow-up, metal-on-polythene and ceramic-on-polythene bearings with small heads showed higher risk for revisions compared with metal-on-HXP and ceramic-on-HXP bearings with small heads. Similarly, only metal or ceramic-on-polythene bearings with small heads showed inferiority in HHS compared with other bearings. Conventional polyethylene liners showed higher linear wear rates compared with HXP, HXPE, and ceramic liners at 5 and 10 years after surgery, while metal-on-metal and ceramic-on-metal bearings showed higher serum level of cobalt and chromium. ConclusionBearings containing HXP, HXPE, and ceramic liners showed comparable survivorship and hip function at follow-up of 5 and 10 years. Hard-on-hard bearings containing metal had higher serum level of metal ions than others. Bearings containing conventional polyethylene had worse performance in terms of implant survival, hip function, and wear rates. Level of EvidenceLevel I.

Total Hip Arthroplasty via direct anterior approach for osteonecrosis; comparison with primary hip osteoarthritis in a mid term follow up

BackgroundTo determine the mid-term outcomes of conventional cementless Total Hip Arthroplasty (THA) in patients with avascular necrosis (AVN) of the femoral head and compare to patients with primary hip osteoarthritis (OA). MethodA total of 330 consecutive primary THA procedures (AVN and OA) performed between 2010 and 2013 by a single surgeon and in a single center using the direct anterior approach (DAA) were included. Assessments including SF-36, WOMAC, and Harris Hip Scores (HHS) were retrieved from patients before the surgery and at the latest follow-up. Clinical and functional outcomes were compared between the AVN and OA groups. ResultsA total of 294 consecutive THA (AVN = 107, OA = 187) with 104.4 ± 6.2 months follow-up were analyzed, which AVN patients were significantly younger (32.0 vs. 59.6 y/o). Corticosteroid 34 (31.8%), idiopathic AVN 31 (29.0%) and use of unapproved weight gain supplements (UWGS) 23 (21.5%) were the main reasons for AVN. Despite that preoperative scores were comparable (P > 0.05), the HHS, SF-36, and WOMAC scores are significantly higher in the AVN group after THA surgery (P < 0.05). Moreover, flexion and abduction ROM were significantly higher in the AVN group (P < 0.05). Regarding each complication, no significant difference was observed between groups. In the whole sample, there were 5 (1.7%) revisions due to loosening of acetabular components, all the OA group (P > 0.05). ConclusionConventional cementless THA with highly cross-linked polyethylene provides satisfactory mid-term results in patients with AVN with a low rate of postoperative complications. Compared to primary OA patients, this group reaches superior postoperative scores.