PURPOSE:To evaluate intraoperative, pre-resection coronal alignment throughout the range of motion (ROM) in knees undergoing robotic-assisted total knee arthroplasty (ra-TKA), and to assess its relationship with the Coronal Plane Alignment of the Knee (CPAK) and the Robotic Evaluation of Articular Laxity (REAL) classifications. METHODS:Three hundred fifty-two consecutive knees undergoing primary ra-TKA using functional alignment were included in this single-surgeon, platform and implant retrospective cohort study. Intraoperative coronal laxity was assessed before bone resections at 0°, 45° and 90° of flexion, under surgeon-applied manual varus and valgus stress without a tensioning device. Laxity was recorded as the maximum angular deviation from the neutral coronal axis and shown as an excursion bar. At each flexion angle, a coronal phenotype was defined: neutral if the bar crossed the neutral axis, varus if entirely within negative hip-knee-ankle (HKA) values and valgus if entirely within positive. By combining the phenotypes at 0°, 45° and 90°, a composite 'REAL HKA phenotype' was derived. Associations between phenotype stability and the CPAK and REAL classifications were evaluated. RESULTS:Fourteen phenotypes were identified. Overall, 73.6% of knees demonstrated a stable phenotype. Phenotype stability varied significantly across CPAK groups (χ2 = 60.12, p < 0.001) and was lowest in valgus knees. Within each alignment group, apex direction influenced phenotype stability; Class IV had lower odds than I (odds ratio [OR] 0.28, 95% confidence interval [CI] 0.11-0.72) and Class V had lower odds than II (OR 0.23, 95% CI 0.09-0.60). REAL flexion grouping was also associated with stability (χ2 = 9.94, p = 0.007). Multivariable analysis confirmed independent associations of CPAK and REAL flexion grouping with phenotype stability (χ2 = 63.26, p < 0.001, Nagelkerke R2 = 0.24). CONCLUSIONS:Coronal behaviour across the ROM varies in knees undergoing ra-TKA. Both constitutional alignment and soft-tissue balance are associated with dynamic coronal phenotype stability. LEVEL OF EVIDENCE:Level IV, retrospective case series.

Developmental dysplasia of the hip (DDH) remains a leading cause of early hip osteoarthritis and poses considerable technical challenges during total hip arthroplasty.Existing classification systems focus on the abnormal relationship between the femoral head and the acetabulum without emphasising the femoral morphological variations, which are equally significant in surgical planning.Dysplastic femora often demonstrate excessive neck anteversion, variable neck–shaft angles, reduced offset, and metaphyseal–diaphyseal mismatch with narrow intramedullary canals. These anatomical variations often compromise the abductor mechanism and alter hip biomechanics.Thorough preoperative planning is crucial and should include the evaluation of leg-length discrepancy, reconstruction of the hip centre of rotation, assessment of femoral version and canal morphology, implant selection, and consideration of femoral shortening osteotomy. Computed tomography-based planning can enhance preoperative planning in complex cases.Both cemented and cementless stems align with positive findings in DDH patients. Cemented stems enable reliable version control, decrease intraoperative fracture risk, and may be beneficial for patients with poor bone quality. In mild cases, most uncemented stems are suitable. More severe deformities necessitate specialised implant designs with conical fluted stems, which provide strong fixation and excellent long-term survivorship. Modular and custom-made options also achieve favourable outcomes in high-grade deformities.Femoral shortening osteotomies are often needed to restore biomechanics, correct abnormal version, and prevent nerve injury during reduction. The subtrochanteric osteotomy has been linked with excellent results in treating severe DDH.High-quality research is essential to deepen our understanding of proximal femur morphological abnormalities and to enhance surgical results.

Background/objectives: Evidence on gait and postural recovery after robotically assisted total knee arthroplasty (raTKA), particularly with the ROSA system, remains limited. This study compared early gait, postural, functional, and patient-reported outcomes (PROMs) between ROSA raTKA and manual TKA (mTKA), with PROMs also assessed at final follow-up. Methods: This comparative cohort study included primary TKA patients treated by a single senior surgeon using the same implant and alignment strategy. Patients underwent either ROSA raTKA or mTKA. At three months, a senior physiotherapist assessed quadricep and tibialis anterior maximum voluntary isometric strength (MVIS), centre-of-mass (CoM) kinematics, lower-limb weight distribution, timed-up-and-go (TUG), range of motion (ROM), KOOS Pain, activities of daily living (ADL), and quality of life (QoL). The same KOOS domains were compared at final follow-up. Results: Seventy primary TKAs were included: 46 raTKAs and 24 mTKAs. No intraoperative complications occurred. Groups were comparable for age, BMI, sex, grip strength, and preoperative KOOS. At three months, no significant differences were found in quadricep MVIS (p = 0.257), tibialis anterior MVIS (p = 0.327), CoM kinematics (p = 0.066), weight distribution (p = 0.189), TUG (p = 0.599), ROM (p = 0.165), or KOOS domains. At final follow-up, KOOS-ADL (p = 0.041) and QoL (p = 0.032) were better in the raTKA group, but after Holm-Bonferroni correction, they were no longer significant (QoL, p = 0.384; ADL, p = 0.451). Conclusions: ROSA raTKA showed comparable early gait and postural recovery to mTKA. The marginal differences in KOOS domains are exploratory, as they were no longer significant after multiple-comparisons correction.

BACKGROUND:Robot-assisted total knee arthroplasty (TKA) enables objective assessment of mediolateral (ML) balance; however, comparisons across cohorts remain difficult because "imbalance" has been poorly defined. The Robotic Evaluation of Articular Laxity (REAL) classification was proposed to standardize ML imbalance using a 3 × 3 framework, but independent replication of this novel classification has not been performed. METHODS:We retrospectively reviewed 386 robot-assisted TKAs for osteoarthritis. Medial and lateral extension and flexion gaps were recorded before bone resection and at procedure end. ML imbalance was calculated as signed and absolute values. Primary outcomes were the distribution and normality of signed ML imbalance and the goodness-of-fit of varus REAL category frequencies versus the original REAL report using thresholds of 2.5 and 5.0 mm. Exploratory analyses evaluated patient-reported outcomes across initial REAL categories. RESULTS:In the full cohort, initial signed ML imbalance deviated from normality, whereas varus initial extension imbalance was nearly normal (1.08 ± 2.79 mm). Final absolute ML imbalance was about 1 mm in extension and 1.0-1.3 mm in flexion, with significant paired reductions in both (both p < 0.001). Varus REAL category frequencies differed from the original report, but deviations were modest and concentrated in a subset of cells. Patient-reported outcomes did not differ across initial REAL categories. CONCLUSIONS:In this independent robot-assisted TKA cohort, key features of the REAL framework were replicated in varus knees. Intraoperative balancing substantially improved ML balance, supporting the descriptive utility of REAL for organizing intraoperative balance phenotypes across cohorts.

Background. Few studies assess gait in robotically assisted total knee arthroplasty (raTKA); none in ROSA raTKA patients. Methods Maximum voluntary isometric strength (MVIS), body centre-of-mass (COM) walking kinematics, body-weight distribution, time-up-and-go (TUG) test, quality of life, and range of motion (ROM) were evaluated in three postoperative months between manually TKA (mTKA) and raTKAs. A surgeon performed all procedures using the same technique. Results Forty-six uncomplicated primary raTKAs and 24 mTKAs were included, showing similar demographics, grip strength, and preoperative KOOS scores. At three months, there were no significant differences in quadriceps (p = 0.869), tibialis MVIS (p = 0.327), COM kinematics (p = 0.801), body-weight distribution (p = 0.189), TUG (p = 0.59), and ROM (p = 0.165). Patient satisfaction was significantly higher in the raTKA group (p = 0,048) and furthermore numerical differences favoring the raTKA group were observed in tibialis anterior MVIS, weight distribution, TUG, and ROM, even though there were no statistically significant differences. Conclusions At three months post-operation, ROSA raTKA resulted in significantly higher patient satisfaction but did not yield statistically differences in gait, posture, or strength outcomes compared to mTKA. The observed non-significant numerical differences in favor of the raTKA grpoup, should be explored in larger, long-term, randomized controlled trials.

Background/Objectives: The optimal treatment for femoral neck fractures (FNFs) in the elderly remains unclear. Internal fixation, bipolar hip hemiarthroplasty (BH), standard total hip arthroplasty (THA), or dual mobility (DM-THA) cups have been employed, each presenting various advantages and disadvantages. This systematic review and meta-analysis evaluated comparative studies of BH and DM-THA in FNFs among the elderly, aiming to ascertain differences in outcomes, including functional recovery, patient-reported outcome measures, implant survival, complications, and mortality rates. Methods: This meta-analysis followed PRISMA 2020 guidelines with a pre-registered PROSPERO protocol (CRD420251065762). A comprehensive search of electronic databases and grey literature included only comparative studies of BH and DM-THA in patients over 65 years with FNFs. Results: Sixteen studies were eligible, comprising four randomised controlled trials and twelve retrospective comparative studies involving 11,460 patients (10,036 BH; 1424 DM-THA). Patients with DM-THA exhibited a higher postoperative Harris Hip Score (4.55, p < 0.0001), alongside a lower dislocation risk ([OR] 2.77, p < 0.0001), a reduced revision rate ([OR] 2.36, p < 0.0001), and decreased mortality ([OR] 1.94, p < 0.0001). The operative time was somewhat longer in the DM-THA group, by 12.71 min, and blood loss was greater by 121 mL, indicating significant heterogeneity across the studies. Conclusions: DM-THA for FNFs in elderly patients results in improved functional recovery and lower dislocation, reoperation, and mortality risk. However, longer operative times and increased blood loss remain significant considerations. Further, well-designed comparative studies are required to evaluate overall cost-effectiveness and define the optimal age threshold, beyond which the limitations of DM-THA may outweigh its benefits.

Computational Medical Extended Reality ( CMXR ), brings together life sciences and neuroscience with mathematics, engineering, and computer science. It unifies computational science (scientific computing) with intelligent extended reality and spatial computing for the medical field. It significantly differs from previous “Clinical XR” and “Medical XR” terms, as it is focusing on how to integrate computational methods from neural simulation to computational geometry, computational vision and computer graphics with deep learning models to solve hard problems in medicine and neuroscience: from low-code/no-code/genAI authoring platforms to deep learning XR systems for training, planning, real-time operative navigation, therapeutics, and rehabilitation.

Background: Tranexamic acid (TXA) has become a cornerstone in total hip arthroplasty for reducing blood loss and minimizing transfusion requirements. However, its influence on postoperative infection rates, including surgical site infections and periprosthetic joint infections (PJIs), remains a topic of debate. This systematic review aims to explore the association between tranexamic acid use and infection rates in total hip arthroplasty. Methods: Following PRISMA 2020 guidelines, an electronic search was performed in the PubMed, Scopus, Web of Science, Cochrane, and Epistemonikos databases. A PICO-based question was developed to select relevant studies, which were assessed for quality using the MINORS tool for non-randomized studies and the RoB 2 tool for randomized controlled trials (RCTs). This review critically appraises three studies, including one RCT and two retrospective cohort studies. Results: Of 277 studies identified, 3 met inclusion criteria, totaling 146,227 patients. Findings indicate that tranexamic acid is generally associated with reduced periprosthetic joint infections and surgical site infection rates, with some variability based on administration routes and dosages. Despite these promising results, methodological limitations in the included studies underscore the need for further high-quality research to establish optimal tranexamic acid protocols. Conclusions: In summary, this systematic review indicates that TXA could reduce postoperative infection rates following total hip arthroplasty (THA). Further well-designed randomized controlled trials are required to validate these findings and determine the best dosing and administration strategies. PROSPERO registration: CRD42024589078.

Diabetes mellitus (DM) is associated with an increased risk of fractures, mainly due to impaired bone architecture and microvascular complications. Whether DM is also associated with increased risk of sarcopenia is not yet known, with studies yielding inconclusive results. The aim of this study was to systematically review and synthesize the best available evidence regarding the association between DM and sarcopenia risk. A comprehensive search was conducted in PubMed, CENTRAL and Scopus databases. Data are expressed as odds ratio (OR) with 95% confidence intervals (CI). The I 2 index was employed for heterogeneity. Only studies which had implemented at least two of the three criteria for sarcopenia diagnosis (low muscle mass, muscle strength and/or muscle performance), as defined by the international studying groups, were included. Fifteen studies fulfilled eligibility criteria, yielding a total of 1832 patients with type 2 DM (T2DM) and 1159 cases of sarcopenia. Patients with T2DM demonstrated a higher risk of sarcopenia compared with euglycemic subjects (OR 1.55, 95% CI 1.25–1.91, p < 0.001; I 2 34.6%). This risk remained significant when analysis was restricted to studies matched for age and sex. Sarcopenia risk was independent of disease definition or study design. Notably, T2DM patients presented lower muscle performance and strength compared with euglycemic subjects, whereas no difference in muscle mass was observed between groups. Patients with T2DM have an increased risk of sarcopenia compared with euglycemic subjects.

INTRODUCTION:Limited data indicate demographic differences between peritrochanteric and subcapital hip fractures. This study aimed to document the 20-year hospitalisation rates for hip fractures at a tertiary hospital and compare the prevalence and demographics between the two types of hip fractures. MATERIALS AND METHODS:This retrospective study examined the electronic records of patients admitted for hip fractures at our hospital from January 2004 to August 2023, utilising the 10th revision of the International Classification of Diseases codes. We collected demographic data encompassing age, sex, and fracture characteristics. RESULTS:A total of 5,987 hip fractures (55.4% peritrochanteric and 44.6% subcapital) were included. The number of patients admitted with hip fractures decreased during our country's economic crisis and the COVID-19 pandemic. The incidence of subcapital and peritrochanteric hip fractures over the two decades was comparable (p = 0.232). There were two-and-a-half times more female cases than male cases. Peritrochanteric fractures were more common than subcapital fractures in both sexes, but the ratio between the sexes was comparable (p = 0.532). A significant difference was observed in the mean age (years) of women (80.4 ± 10.1) compared to men (77.0 ± 14.1) (p < 0.001) and between subcapital (77.8 ± 11.9) and peritrochanteric hip fractures (80.7 ± 10.9) (p < 0.001). The mean age of women with peritrochanteric fractures (81.9 ± 8.9) was statistically different from those with subcapital hip fractures (78.4 ± 11.0) (p < 0.001). This difference was not significant for men (p = 0.114). Individuals over 75 years old were involved in 76.8% of all cases, with the majority being women (57.5%). There was a significant increase in the ratio of female to male cases over 75 years (p < 0.001). CONCLUSIONS:Our research indicated that women are more likely to develop hip fractures than men. Additionally, peritrochanteric fractures are more common than subcapital fractures. The risk of developing hip fractures increases with age, particularly after 75. Furthermore, hip fractures in women occur significantly later than in men, and the same applies to peritrochanteric compared to subcapital fractures. There may be demographic disparities between peritrochanteric and subcapital hip fractures.

PURPOSE:Currently, there is no widely accepted method for measuring soft-tissue laxity and defining a balanced total knee arthroplasty (TKA). We aim to evaluate whether robotic technology can facilitate the categorization of intraoperative knee laxity. METHODS:Our study was conducted in two phases. A senior surgeon performed imageless robotically assisted TKAs (ra-TKAs) using functional alignment. The first phase included 120 patients. Following the surgical approach, the medial and lateral soft-tissue laxity was recorded in extension and 90° flexion. The distribution of the difference and sum of laxities in extension and 90° flexion was assessed to classify laxity phenotypes. The second phase validated the classification in 102 additional ra-TKAs. Laxity phenotypes were evaluated at the start and end of the procedure. RESULTS:Laxity difference followed a normal distribution, facilitating categorization into three groups, with a standard deviation of 2.5 mm. Three categories of mediolateral laxity severity difference were established: < 2.5 mm, 2.5-5 mm, and > 5 mm. These laxity groups were coded in extension as 1, 2, and 3 and in flexion as A, B, and C, respectively. Nine laxity phenotypes emerged from the combination of the extension and flexion categories (1A-C, 2A-C, and 3A-C). Phenotypes 1A and 1B were the most common at the operation' beginning, while phenotypes 3B and 1C were the rarest. At the end of the operation, 93% were categorized as class 1A and 1B, defining the "balanced area". CONCLUSION:Our study recognized nine intraoperative soft-tissue knee laxity phenotypes, potentially laying the groundwork for a surgical consensus on knee balancing.

The piriformis muscle (PM) is important for posture and preventing falls. It is a key landmark for hip surgery. The PM function is reported to be increasingly important for improving total hip arthroplasty (THA) outcomes and reducing complications. This scoping review aims to map and summarize the literature on the anatomy and function of the PM and the outcomes of clinical studies on THA preserving the PM to improve readers' understanding and identify areas for further research. A scoping review following the PRISMA guidelines was conducted using PubMed and Scopus from their inception until June 2023. We used the search term 'piriformis' or 'PM' to include all PM-related studies. Two independent reviewers screened abstracts and full texts to select key aspects of PM anatomy and function and the main clinical THA studies reporting outcomes on PM preservation. Fifty-seven studies published between 1980 and 2023 met our inclusion criteria. During hip surgery, the PM anatomy, including its origin and insertion, muscle belly, and relation to other short hip rotators and the sciatic nerve, can vary greatly, making it difficult to recognize. The current literature on PM-preserving THA and hemiarthroplasty clinical studies is limited. It suggests potential benefits in terms of hip stability, dislocation risk, and functional outcomes compared to no PM preservation in short-term follow-up. Identifying and preserving the PM during hip surgery may be difficult due to its variable anatomy and its relation to surrounding structures. Although the literature supporting PM preservation potentially indicates better outcomes, further high-level research studies are needed.

Background:Serotonin Reuptake Inhibitors (SRIs) are commonly utilised antidepressants among populations in Western countries; however, their use has been linked to adverse effects and postoperative complications. This systematic review assessed the risk of both early and late perioperative complications in SRIs users undergoing elective total hip arthroplasty (THA) and knee arthroplasty (TKA) compared to non-users. Methods:This study adhered to the 2020 PRISMA guidelines. A comprehensive search of PubMed, Science Direct/Scopus, and the Cochrane Database of Systematic Reviews was conducted from inception until January 2025. Comparative studies examining SRI users and non-users undergoing elective THA or TKA that addressed at least one postoperative outcome (blood loss, postoperative haemoglobin reduction, transfusion rate, length of stay, readmission and revision rate) were included. The Newcastle-Ottawa Scale was employed to evaluate the quality of the included studies. A meta-analysis was performed to assess the risk of transfusion, utilising a random-effects model. Results:Ten comparative cohort studies, including two prospective and eight retrospective studies, were included in this analysis, involving 2,098,833 patients who underwent either elective THA or TKA. Among these patients, 418,527 were using SRIs during the perioperative period, with a mean age of 65.2 years. Our meta-analysis revealed an odds ratio of 1.78 (95 % CI, 1.11, 2.83; p = 0.02) concerning the blood transfusion rate in patients utilising SRIs, although it was characterised by considerable heterogeneity (I2 = 97 %). The findings regarding length of stay, readmission rate, and revision rate were inconclusive. Conclusion:The use of SRIs in patients undergoing elective THA and TKA may be linked to a slightly increased risk of bleeding and need for blood transfusion. However, considering the potential benefits of these medications for this patient group, it remains uncertain whether discontinuing them during the perioperative period is advisable. More high-quality studies are required to establish an etiological relationship.

Introduction The prevalence of periprosthetic femoral fractures (PFFs) in Greece has not been previously documented. This study aims to determine the prevalence of PFFs in a Greek population over the past 20 years, using data from a referral centre. Methods A retrospective analysis of PFFs was conducted at a Greek academic orthopaedic department, covering the period from 2004 to 2023. Demographic data, PFF types, treatment methods, time from admission to surgery, length of hospital stay (LOS), and operative times were recorded and compared between the two decades. Results The study included 244 patients with PFFs, with a mean age of 78.2 years. Most patients were female (86.5%, p < 0.001). The incidence of PFFs significantly increased between the first and second decades (mean: 9.8 vs. 14.6 cases per year, p = 0.01). This increase was particularly evident in fractures around total knee arthroplasties (TKAs) (p = 0.0027). Treatment choices between internal fixation and revision arthroplasty remained consistent over time for PFFs around total hip arthroplasties (THAs) and TKAs (p > 0.05). However, the LOS and the time from admission to surgery significantly decreased from the first to the second decade (p = 0.001 and p = 0.02), respectively. Conclusion This study is the first to document PFFs in a Greek population, showing a notable increase in incidence, higher prevalence among females, consistent treatment methods, and a reduction in the time from admission to surgery and LOS over the past decade.

PURPOSE:Modifying femoral morphology after total knee arthroplasty (TKA) poses a potential risk for ligament-imbalances and patella mal-tracking. The purpose of this study was primarily to quantify TKA-induced stuffing around the femur and secondarily assess the effect of femoral rotation (FR) on trochlear and condylar anatomy-changes. METHODS:Knee anatomy-modification was quantified in 69 robotic-assisted TKAs utilising tibia-based functional alignment (FA). Caliper-measurements were performed on the medial (Med), central (Ctr), and lateral (Lat) sides of the following resection planes: anterior trochlea (AT), oblique trochlea (OT), distal condyles (DC), posterior condyles (PC) and tibia (TIB). The same caliper-measurements were performed on the femoral components used to calculate bone-implant differences and analyse possible patterns of postoperative trochlear anatomy-modifications (TAM) and condylar anatomy-modifications (CAM). Over- or understuffing analysis for different FRs and regression analysis were conducted to assess the effect of FR on CAM and TAM. RESULTS:TAM results were Lat-AT -3.2 mm ([95% confidence interval [CI]: -3.71 to -2.63], p < 0.001), Ctr-AT 0.7 mm ([95%CI: 0.22-1.32], p = 0.02), and Ctr-OT -1.7 mm ([95%CI: -1.85 to -0.93], p < 0.001) with stuffing > 2 mm in 60.9%, 39.1%, and 39.1%, respectively. CAM results were Med-DC -3.6 mm ([95%CI: -4.14 to -3.05], p < 0.001) and Lat-PC 3.0 mm ([95%CI: 2.48-3.38], p > 0.001) with stuffing > 2 mm in 78.3% and 63.8%. FR (3.8 ± 2.6°, range: -1.6° to 8.5°) affected mostly the anterior (r = -0.40, p < 0.001) and posterior (r = 0.71, p < 0.001) aspects of the knee but hardly the OT plane (r = 0.06, p = 0.624) and the trochlear groove to its full range of flexion (r = 0.21, p = 0.17). External FR 2° was associated with the lowest incidence of femoral stuffing > 2 mm and ≥ 4 mm. CONCLUSIONS:FA-typical modification-pattern was a TAM with lateral facet understuffing, and CAM with medial distal understuffing and lateral posterior overstuffing. Trochlear groove height was non-significantly affected by FR. FA with the current off-the-shelf implant induces the lowest stuffing rates when set in 2° external femoral rotation. LEVEL OF EVIDENCE:Level II.

Introduction: This systematic review aims to critically assess the literature comparative studies investigating collared and collarless Corail stem in primary total hip arthroplasty (THA) to find differences in revision rates, radiographic and clinical outcomes, and postoperative complications between these two types of the same stem. Methods: Eligible studies were found by searching PubMed, Science Direct/Scopus, and the Cochrane Database of Systematic Reviews from conception till May 2023. The PRISMA guidelines were followed. The investigation encompassed randomized controlled trials, case series, comparative, cohort, and observational studies that assessed at least one comparative outcome or complication between collared and collarless Corail stems. Results: Twelve comparative studies with 90,626 patients undergoing primary THA were included. There were 40,441 collared and 58,543 collarless stems. The follow-up ranged from 12 to 360 months. Our study demonstrated no significant difference in stem revision relative risk (RR = 0.68; 95% confidence interval (CI), 0.23, 2.02; p = 0.49), number of radiolucent lines (RR = 0.3; 95% CI, 0.06, 2.28; p = 0.29) and overall complication risk (RR = 0.62; 95% CI, 0.22, 1.76; p = 0.37) between collared and collarless stems. The collared stems demonstrated significantly lesser subsidence (mean difference: 1.01 mm; 95% CI, −1.77, −0.25; p = 0.009) and risk of periprosthetic fractures (RR = 0.52; 95% CI, 0.29, 0.92; p = 0.03). Conclusion: The comparative studies between collared and collarless stem groups showed similar survival and overall complication rates and functional outcomes. The similar revision rates between groups make the impact of higher subsidence for collarless stems uncertain. The lower risk of periprosthetic fractures in the collared stems group must be clarified further but could be related to increased rotational stability.

Syndromes associated with osteochondrodysplasia, short stature, and DDH are rarely reported in the literature. Total hip arthroplasty (THA) in such cases is a complex procedure with a high rate of complications and difficulties. In this case report, we describe the staged bilateral complex primary THA of a patient with the rare occurrence of a syndrome involving osteochondrodysplasia and DDH, highlighting the surgical challenges and importance of the right prosthesis selection.

The dual mobility cup (DMC) reduces the dislocation rates in total hip arthroplasty (THA). DMC systems include anatomical (non-modular or monoblock) (ADM) and modular dual mobility (MDM) components (Stryker Orthopaedics, Mahwah, NJ, USA). This review aims to assess differences between these two types of DMC implants concerning dislocation and revision rates, as well as patient-reported outcomes. This systematic review and meta-analysis of studies reports data from patients undergoing primary THA using MDM and/or ADM implants. Following the PRISMA guidelines, we analyzed articles from Science Direct/Scopus, PubMed, and the Cochrane Database of Systematic Reviews. We compared dislocation rates, revisions for any reason, aseptic loosening, infections, fractures, and functional outcomes between ADM and MDM components. Eleven studies were considered eligible for further analysis. A total of 3369 patients (mean age = 65.4 years) underwent primary THA, including 3386 DMC implants. The mean follow-up for the MDM and ADM groups was 2.9 years and 3.9 years, respectively. The study revealed one dislocation in the MDM and none in the ADM. By proportion metanalysis, the review did not show statistical differences in all-cause revisions (p = 0.93, [CI [0.01;0.02]) or periprosthetic fractures (p = 0.18, CI [0.01;0.02]). MDM and ADM systems, both, represent safe DM options regarding dislocation, all-causes revisions and functional outcomes.