Medial Closing Wedge High Tibial Osteotomy Accurately Corrects Genu Valgum without Iatrogenic Deformity or Complications: A Consecutive Series of Thirty-one Procedures.

Introduction: Angular deformities of the tibia and femur lead to mechanical axis deviation (MAD) of the lower limb and malorientation of the joints adjacent to the deformity. The current study analyses the outcomes of using a medial closing wedge high tibial osteotomy (MCWHTO) for the management of genu valgum with high medial proximal tibial angle (MPTA), and combined MCWHTO with lateral opening-wedge distal femoral osteotomy (LOWDFO) in the setting of concomitant genu varum with low lateral distal femoral angle (LDFA). Methods: There were 18 high tibial osteotomy (HTO)-only and 13 combined HTO + distal femoral osteotomy (DFO) procedures performed. The primary radiographic outcome variables included postoperative MPTA and MAD (in mm). The accuracy of MAD correction was expressed as a percentage. The postoperative posterior proximal tibial angle (PPTA) and limb length discrepancy (LLD) were also measured as secondary radiographic outcome variables. The clinical outcome variables included intraoperative surgical complications (e.g., hinge fracture), all-causes for revision, union rate, time to union, and postoperative knee range of motion. Functional outcomes used included the LDSRS, PROMIS, and EuroQOL scores. Results: The mean preoperative MPTA was 92.9° (SD = 1.81, range: 88-96). After surgical correction, the mean MPTA was 86.0° (SD = 1.80, range: 83-90) (p < 0.0001). The mean preoperative MAD was 32.5 mm (SD = 20.16, range: 10-77) lateral to the centre of the knee joint. The mean postoperative MAD was 2.44 mm medial to the centre of the joint (SD = 7.13, range: 13 medial - 15 lateral) (p < 0.0001). The mean change in MAD achieved through surgical correction was 38.16 mm (SD = 17.94, range: 13-77). The accuracy of MAD correction was 96.1% (SD = 0.06%, range: 81.25-100%). The time to unassisted WB was a mean of 75 days (SD = 44.5, range: 44-242).There was a single stable hinge fracture and one case of chronic regional pain syndrome diagnosed. There were no cases of non-union and no indications for revision surgery in any case. Conclusion: Medial closing wedge high tibial osteotomy is an effective surgical procedure for the management of genu valgum deformity. The MPTA, LDFA, and MAD can be accurately corrected without significantly altering PPTA or limb length. It may be combined with open lateral distal femoral osteotomy for cases with femoral and tibial contributions to deformity without significantly impacting clinical outcomes. Functional outcomes, specifically relating to self-image are significantly improved after the MCWHTO has been performed. How to cite this article: Sheridan GA, Page BJ, Greenstein MD, et al. Medial Closing Wedge High Tibial Osteotomy Accurately Corrects Genu Valgum without Iatrogenic Deformity or Complications: A Consecutive Series of Thirty-one Procedures. Strategies Trauma Limb Reconstr 2024;19(2):82-86.

Short-term survival of the cementless triathlon total knee arthroplasty in a young patient cohort.

BACKGROUND: The purpose of this study is to assess the short-term survivorship of a new cementless total knee arthroplasty (TKA) design in comparison to its cemented predecessor design in a young patient cohort less than 65 years of age. METHODS: We performed a retrospective cohort study of all primary TKAs (cemented and cementless) in patients under the age of 65 at the time of the index procedure, in a single institution between May 2018 and May 2019. Primary outcome variables included aseptic revision and all-cause revision. Operative time was a secondary variable. Independent variables considered included age, sex, body mass index (BMI), American Society of Anesthesiologists (ASA) grade, implant type (cruciate-retaining (CR) or posterior-stabilised (PS)) and the use of cemented or cementless implants. RESULTS: There were 106 cemented TKAs and 152 cementless TKAs (Triathlon, Stryker Inc, Mahwah, NJ ) implanted. The minimum follow-up for all cases was 2 years (mean cementless 32.5 months, mean cemented 34.9 months). Of the entire 258 implants only 2 were revised. Both revisions occurred in the cemented cohort for prosthetic joint infection (PJI). The all-cause revision rate in the cementless cohort was 0% compared to 1.8% in the cemented cohort (p = 0.168). Operative times were significantly reduced from 62 min in the cemented cohort to 52.2 min in the cementless cohort (p < 0.001). CONCLUSION: In a young patient cohort, the cementless Triathlon TKA demonstrates excellent survivorship at short-term follow-up with significant reductions in operative times when compared to the cemented Triathlon TKA.

Hypertrophic nonunion management with distraction osteogenesis: a scoping review of the literature.

Introduction: Traditionally, stiff hypertrophic nonunions have been managed with open preparation of the nonunion site, which is then secured with internal fixation. Alternative surgical options are available including distraction osteogenesis with an external fixator. There is currently a limited amount of literature pertaining to the use of distraction osteogenesis in the management of hypertrophic nonunion. The aim of this systematic review was to collate and assess the effectiveness of distraction osteogenesis (DO) in the management of hypertrophic nonunions and to evaluate the complications that are commonly reported in the literature. Methods: We searched for articles pertaining to the treatment of hypertrophic nonunion using distraction osteogenesis. Several electronic bibliographic databases and clinical trial registries were searched using the MeSH terms "hypertrophic non-union," "distraction osteogenesis," "stiff non-union," and "External Fixation" in various combinations to return the maximal number of studies for review. We performed a systematic review and identified a total of 11 studies eligible for review. Results: The review of the literature demonstrated that this technique is highly effective in achieving bony union with minimal complications. The most common complication is mild superficial pin site infections, usually managed with oral antibiotics and effective wound hygiene. Other complications reported were deep pin tract infections, broken hardware, and deformity recurrence due to collapse of regenerate bone. Conclusion: The use of distraction osteogenesis with external fixator devices is an effective and safe method for producing bony union in hypertrophic nonunions. There were minimal associated complications.

Extra-articular Osteotomy for the Management of Intra-articular Tibial Plateau Valgus Malunion.

OBJECTIVES: To report a case series of extra-articular osteotomies for the management of intra-articular tibial plateau malunions and to assess the ability to correct deformity and improve knee range of motion (ROM). METHODS: . DESIGN: Retrospective case series. SETTING: Academic, tertiary, referral center. PATIENT SELECTION CRITERIA: Adult patients with tibial plateau fracture malunion treated with extra-articular osteotomy of the femur and/or tibia between 2014 and 2023. OUTCOME MEASURES AND COMPARISON: Mechanical axis deviation (MAD), medial proximal tibia angle (MPTA), lateral distal femoral angle (LDFA), and posterior proximal tibia angle (PPTA) correction; knee ROM; and time to weight bearing. RESULTS: There were 7 patients included, 6 (85.7%) were female and 1 (14.3%) were male. The median age was 43.5 years (IQR 38.5-51, range 32-62). Four (57.1%) patients were treated with a high tibial osteotomy (HTO), and 3 (42.9%) patients were treated with an HTO and distal femoral osteotomy. One patient had concomitant supramalleolar osteotomy with HTO to address distal tibia procurvatum and valgus. Four were treated with hexapod frames, and 3 were treated with plates and screws. Median follow-up was 22.5 months (IQR 10.5-107 months, range 7-148 months). Surgical intervention corrected median radiographic measures of valgus malalignment preoperatively relative to postoperative values. This included MAD (42.5 mm-0 mm), valgus angle (12.5 degrees-1.5 degrees), MPTA (95 degrees-88.0°), and LDFA (86.0°-87.3 degrees). Surgical intervention increased maximal knee range of motion preoperatively to postoperatively. Median time to full weight bearing was 81.5 days (IQR 46-57 days, range 41-184 days). Two patients were converted to total knee arthroplasty after 5 and 10 years following HTO with hexapod frame. CONCLUSIONS: Extra-articular osteotomy is an effective treatment for addressing intra-articular malunion after tibia plateau fractures. It is effective in correcting the MAD, valgus deformity, MPTA, LDFA, PPTA, and improving knee ROM (measured through knee extension and flexion). LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Percutaneous removal of hardware after orthopedic surgery: Is it safe? and What are patients saying?

OBJECTIVES: To analyze our patient's complication profile and rate after removal of hardware (ROH) surgery, and survey our patients to ask their overall status and improvement in symptomatology post-operatively. DESIGN: Retrospective chart review and survey. SETTING: Academic, tertiary referral center. PATIENTS/PARTICIPANTS: 173 patients with 314 pieces of hardware. Seventy-six patients (43.9%) responded to our survey. INTERVENTION: ROH surgery. MAIN OUTCOME MEASUREMENTS: Patient demographics and complications were recorded. All patients were sent a brief 3-question survey which asked: (1) Why did you get your hardware removed? (2) How did your overall status change after ROH? (3) How did the ROH affect your stiffness, pain, swelling, and mobility? RESULTS: There were 10 complications (5.5%): 5 infections, 2 with unresolved pain, 1 hematoma, 1 chronic regional pain syndrome exacerbation, and 1 recurrent deformity. All infections were treated with oral antibiotics and improved. All other complications resolved with treatment except for the patient who developed recurrent deformity. Patients underwent ROH surgery because their doctor suggested it (76.3%) and to improve mobility (39.5%). 86.9% reported their overall status improved after ROH. They improved regarding stiffness (73.7%), pain (73.6%), swelling (61.8%), and mobility (76.3%). Similar results were seen among different implants removed. CONCLUSIONS: The majority of patients who underwent percutaneous ROH were satisfied. They reported improvement in stiffness, pain, swelling and mobility (greatest improvement). The complication rate was low (5.5%). ROH can be a meaningful operation to patients allowing them to improve their quality of life with a low complication rate. LEVEL OF EVIDENCE: Level IV.

The John Charnley Award: The Impact of Human Leukocyte Antigen Genotype on Bacterial Infection Rates and Successful Eradication in Total Hip Arthroplasty.

BACKGROUND: Genetics play an important role in several medical domains; however, the influence of human leukocyte antigen (HLA) genotype on the development of periprosthetic joint infection (PJI) in total hip arthroplasty (THA) remains unknown. The primary aim of this study was to determine if HLA genotype is associated with the development of bacterial PJI in THA. Secondarily, we evaluated the association between HLA genotype and PJI treatment success. METHODS: A retrospective, matched, case-control study was performed using prospectively collected data from a single institution. A total of 49 patients who underwent primary THA were included, with a mean follow-up of 8.5 years (range, 4.2 to 12.9). The 23 cases (PJI) and 26 controls (no PJI) were matched for age, sex, follow-up, body mass index, primary diagnosis, and comorbidities (P > .05). High-resolution genetic analysis targeting 11 separate HLA loci was performed in all patients using serum samples. The HLA gene frequencies and carriage rates were determined and compared between cohorts. A subgroup analysis of PJI treatment success (18) and failure (5) was performed. Statistical significance was set at P = .10 for genetic analysis and at 0.05 for all other analyses. RESULTS: There were 4 HLA alleles that were significantly associated with the development of PJI. The 3 at-risk alleles included HLA-C∗06:02 (odds ratio 5.25, 95% CI [confidence interval] 0.96 to 28.6, P = .064), HLA-DQA1∗04:01 (P = .096), and HLA-DQB1∗04:02 (P = .096). The single protective allele was HLA-C∗03:04 (odds ratio 0.12, 95% CI 0.01 to 1.10, P = .052). There were no specific HLA alleles that were associated with treatment success or failure. CONCLUSIONS: This study suggests that there are at-risk and protective HLA alleles associated with the development of PJI in THA. To our knowledge, this is the first study to demonstrate an association between patient HLA genotype and the development of PJI. A larger study of the subject matter is necessary and warranted.

Distraction osteogenesis in combined sequential use of external fixation and nailing (lengthening and then nailing): An experimental study in rabbits.

Limb lengthening relies on the process of distraction osteogenesis. The active periosteal bone formation has been detected in clinical practice with a lengthening and then nail (LATN) technique but has not been confirmed by experimental studies to date. The aim of this study is to compare the tissue regeneration of the distraction regenerate during tibial lengthening in rabbits using a LATN technique. This study was performed on 54 mature rabbits of the Soviet Chinchilla breed, which were divided into three groups of 18 animals. In group 1 (control), the tibia was lengthened in an external fixator. In group 2, the LATN technique was modeled and in group 3, lengthening over nail (LON) was modeled. The total duration of the experiment was 45 days. On the 10th, 15th, 20th, 30th, and 45th day X-ray, computed tomography and morphological studies were performed. In the experimental groups (2 and 3), a more pronounced periosteal bone formation in the area of regenerate was noted when compared to group 1. In group 2 (LATN), wide cortical plates were formed from the intermediate and periosteal areas. In this group, the maximum densitometric density values were noted. Endosteal bone formation was preserved in all groups. The LON and LATN techniques, when compared with the classical Ilizarov lengthening, do not demonstrate any deficiency in the tissue regeneration of the bone tissue at the regenerate sites. The most powerful bone structures are formed with the sequential use of the external fixation and nailing (LATN).

Navigated Versus Conventional Total Knee Arthroplasty: A Systematic Review and Meta-analysis of Prospective Randomized Controlled Trials.

Background: Recent evidence on the cost-effectiveness of technology in total knee arthroplasty (TKA) demonstrated that navigated computer-assisted methods (N-TKA) is likely to be most cost-effective in the clinical setting. The aim of the current meta-analysis is to compare radiographic, clinical and functional outcomes between conventional TKA (C-TKA) and N-TKA methods. Methods: All prospective randomized controlled trials (pRCTs) comparing primary TKA performed using C-TKA and N-TKA techniques were eligible for inclusion. Radiographic outcomes included postoperative coronal, sagittal and axial component alignment. Clinical outcomes included all-cause revision and aseptic revision. Functional outcomes were analyzed when reported. A random-effects meta-analysis of all available cases was performed. This allowed for all missing data. Results: Normal coronal mechanical alignment of the tibial (p < 0.001) and femoral (p = 0.001) components was achieved more frequently with N-TKA. Normal sagittal mechanical alignment of the tibial component was achieved significantly more with N-TKA (p < 0.010). There was no difference in short-term clinical survivorship (all-cause, p = 0.649; aseptic, p = 0.79) or in functional outcomes reported between groups. There was a clinically significant reduction in the mean C-TKA operative time (87 min, σ = 16.6, 95% CI 76.4-98.8) compared N-TKA (97.6 min, σ = 16.9, 95% CI 86.2-109.1) (p = 0.17). Conclusion: Navigated TKA achieves superior radiographic alignment for femoral and tibial components in both the coronal and sagittal plane. Operative times are 10 min longer in the N-TKA group. Functional outcomes are similar between navigated and conventional groups. Clinical outcomes reported in Level I studies are limited to short-term follow-up so future prospective studies are required.

The Diagnostic Utility of Serum Metal Ion Markers for High-Grade Aseptic Lymphocyte-Dominated Vasculitis-Associated Lesions (ALVALs) in Revision Hip and Knee Arthroplasty: An International Multicenter Study.

BACKGROUND: Aseptic lymphocyte-dominated vasculitis-associated lesions (ALVALs) are typically described in the context of metal-on-metal (MoM) hip bearings. This study explores the diagnostic utility of preoperative serum cobalt and chromium ion levels in determining the histological grade of ALVAL in revision hip and knee arthroplasty. METHODS: This was a multicenter retrospective review of 26 hips and 13 knees assessing the correlation between preoperative ion levels (mg/L (ppb)) and the histological grade of ALVAL from intraoperative specimens. The diagnostic ability of preoperative serum cobalt and chromium levels to determine high-grade ALVAL was assessed using a receiver operating characteristic (ROC) curve. RESULTS: In the knee cohort, there was a higher serum cobalt level in high-grade ALVAL cases (10.2 mg/L (ppb) versus 3.1 mg/L (ppb)) (P = .0002). The Area Under the Curve (AUC) was 1.00 (95% confidence interval (CI) 1.00 to 1.00). There was a higher serum chromium level in high-grade ALVAL cases (12.25 mg/L (ppb) versus 7.77 mg/L (ppb)) (P = .0002). The AUC was 0.806 (95% CI 0.555 to 1.00). In the hip cohort, there was a higher serum cobalt level in high-grade ALVAL cases (333.5 mg/L (ppb) versus 119.9 mg/L (ppb)) (P = .0831). The AUC was 0.619 (95% CI 0.388 to 0.849). There was a higher serum chromium level in high-grade ALVAL cases (186.4 mg/L (ppb) versus 79.3 mg/L (ppb)) (P = .183). The AUC was 0.595 (95% CI 0.365 to 0.824). CONCLUSIONS: Histologically, high-grade ALVAL has significantly higher preoperative serum cobalt and chromium ion levels in revision TKA. Preoperative serum ion levels have excellent diagnostic utility in revision TKA. Cobalt levels in revision THA have a fair diagnostic ability and chromium levels had a poor diagnostic ability.

Factors Associated With Length of Stay for Hip and Knee Arthroplasty: A 20-Year Single-Province Population-Based Analysis of Longitudinal Temporal Trends.

Background: With notable benefits in reducing length of stay (LOS), this study aimed to quantify the temporal trend and the factors contributing to increased LOS for primary and revision total hip (THA and rTHA) and knee (TKA and rTKA) arthroplasty. The study was carried out for a large population-based cohort over a 20-year period. Methods: This was a retrospective population-based study assessing the LOS for all primary and revision THA and TKA procedures between 2003 and 2022. The primary outcome of interest was LOS. Univariate and multivariate analyses were performed to identify associated variables. Results: For the entire dataset, there were 16,677 primary THAs, 13,018 primary TKAs, 3276 (aseptic) rTHAs, 1445 (aseptic) rTKAs, 820 (septic) rTHAs, and 667 (septic) rTKAs. The median LOS over the 20-year period between 2003 and 2022 demonstrated a steady and continuous decline from a median of 5 days (interquartile range 3-7) in 2003 to 1 day (interquartile range 1-2) in 2022. On multivariate analysis, there were a number of factors associated with increasing LOS: year of procedure (P < .0001), procedure type (P < .0001), age (P < .0001), and American Society of Anesthesiologists class (P < .0001). On multivariate analysis, body mass index was not associated with increased LOS (P = .5631). Conclusions: There was a downward trend in LOS for all types of primary and revision THA and TKA. The factors contributing most to a reduction in LOS include the year the procedure was performed, primary THA procedures, aseptic (vs periprosthetic joint infection) revision procedures, younger age, and lower American Society of Anesthesiologists classes.

Signficant Femoral Version Abnormalities and Patient-Reported Quality of Life.

INTRODUCTION: The purpose of this study was to determine how the Limb Deformity-Modified Scoliosis Research Society (LD-SRS) and Patient-Reported Outcomes Measurement Information System (PROMIS) questionnaire scores differ between patients with femoral version abnormalities and healthy control subjects. METHODS: A retrospective database review identified patients with femoral version abnormalities between December 2018 and September 2022. A total of 21 adult patients scheduled for femoral derotational osteotomy and 33 control subjects were included. All individuals completed the LD-SRS and PROMIS questionnaires. RESULTS: Patients with femoral version abnormalities reported significantly worse scores than control subjects on all LD-SRS and PROMIS domains: LD-SRS (Total [3.46 ± 0.66 vs. 4.58 ± 0.37, P < 0.001]; Function/Activity [3.48 ± 0.83 vs. 4.44 ± 0.4, P < 0.001]; Mental Health [3.41 ± 0.96 vs. 4.3 ± 0.73, P < 0.001]; Pain [3.55 ± 0.9 vs. 4.81 ± 0.31, P < 0.001]; and Self-Image/Appearance [3.37 ± 0.79 vs. 4.75 ± 0.43, P < 0.001]) and PROMIS (Function [41.6 ± 7.58 vs. 60.0 ± 7.28, P < 0.001]; Pain Intensity [45.85 ± 8.04 vs. 33.7 ± 4.89, P < 0.001]; Pain Interference [56.78 ± 9.63 vs. 42.8 ± 6.6, P < 0.001]; Global Mental Health [47.97 ± 9.68 vs. 55.3 ± 7.81, P = 0.004]; and Global Physical Health [45.23 ± 7.49 vs. 58.2 ± 7.07, P < 0.001]). DISCUSSION: Patients with femoral version abnormalities reported markedly worse quality of life as measured on the LD-SRS and PROMIS scores compared with healthy control subjects. The combination of these two surveys effectively captures the multifaceted quality-of-life-deficit individuals with excessive femoral version may experience.

The Management of Tibial Bone Defects: A Multicenter Experience of Hexapod and Ilizarov Frames.

INTRODUCTION: Bone defects may be managed with bone transport or acute shortening and lengthening using circular external fixation devices. We performed a multicenter retrospective cohort study to compare the outcomes between the Ilizarov frames and hexapod frames for the management of bone defects. METHODS: Patients treated for bone defects using either Ilizarov or hexapod frames were included for analysis in two specialist institutions. Primary outcomes were time to consolidation, bone healing index (BHI), and external fixator index (EFI). Radiographic parameters included the medial proximal tibial angle, lateral distal tibial angle, posterior proximal tibial angle, and anterior distal tibial angle. RESULTS: There were 137 hexapods and 90 Ilizarov frames in total. The mean time to follow-up was 3.7 years in the hexapod group and 4.0 years in the Ilizarov group. Hexapods had a significantly lower time to consolidation (253 days versus 449 days) (P < 0.0001) and BHI (59.1 days/cm versus 87.5 days/cm) (P < 0.0001). Hexapods had a significantly better EFI (72.3 days/cm versus 96.1 days/cm) (P = 0.0009). CONCLUSION: Hexapods may confer a significant advantage over Ilizarov frames in the management of bone defects. Time to consolidation, radiographic parameters, BHI, and EFI are all superior in hexapods.

The association between weather warnings and hip fractures in the Republic of Ireland.

This study examined the relationship between hip fractures and weather warnings with the hypothesis higher rates of fractures occur during warnings. National hip fracture database and weather warning records were utilised. Higher rates of hip fractures were found with severe warnings. This has implications for planning in future severe warnings. BACKGROUND: Hip fractures represent a significant burden on the Irish Health system with 3666 in 2020. The Irish National Meteorological Service operates a colour coded warning system. Yellow being least severe, while orange represents weather with capacity to impact individuals in affected areas and red represents advice to protect themselves and property. Previous studies investigated the seasonality of hip fractures, which remains but none have investigated the relationship between weather warnings and rates of hip fractures. The hypothesis was that increasing weather warnings would be associated with increased hip fractures. The aim was to investigate the relationship between weather warnings and hip fractures in the Republic of Ireland. METHODS: Comparison of national weather warning archives from 2013 to 2019 to Fracture Database records. Reviews assessed whether fractures occurred on days a weather warning was in place in the individual's local county. A statistical analysis of warning features and their relationship to hip fractures was then performed. Fractures and weather warnings were stratified by county with both a panel and case crossover analysis performed. RESULTS: There was a tendency towards increased incidence of hip fractures with weather warnings in adjusted analysis (IRR 1.02; 95%CI 0.99-1.06; p-value 0.123). Orange warnings were associated with a statistically higher incidence of fractures (IRR 1.06; 1.01-1.12; p-value 0.026). In both panel and case crossover analysis, both orange and yellow warnings were associated with fractures. Red warnings were associated with a lower incidence of fracture on day of warning (adjusted incidence rate ratio 0.92; 0.70-1.22; p-value 0.569) but a higher incidence on the following day (adjusted incidence rate ratio 1.14; 0.88-1.46; p-value 0.313). CONCLUSION: An increased incidence of hip fractures appears to occur during weather warnings. Consideration should be given when preparing for periods of extreme weather, ensuring sufficiently resources.

Identification of protective and 'at risk' HLA genotypes for the development of pseudotumours around metal-on-metal hip resurfacings.

Hip resurfacing remains a potentially valuable surgical procedure for appropriately-selected patients with optimised implant choices. However, concern regarding high early failure rates continues to undermine confidence in use. A large contributor to failure is adverse local tissue reactions around metal-on-metal (MoM) bearing surfaces. Such phenomena have been well-explored around MoM total hip arthroplasties, but comparable data in equivalent hip resurfacing procedures is lacking. In order to define genetic predisposition, we performed a case-control study investigating the role of human leucocyte antigen (HLA) genotype in the development of pseudotumours around MoM hip resurfacings. A matched case-control study was performed using the prospectively-collected database at the host institution. In all, 16 MoM hip resurfacing 'cases' were identified as having symptomatic periprosthetic pseudotumours on preoperative metal artefact reduction sequence (MARS) MRI, and were subsequently histologically confirmed as high-grade aseptic lymphocyte-dominated vasculitis-associated lesions (ALVALs) at revision surgery. 'Controls' were matched by implant type in the absence of evidence of pseudotumour. Blood samples from all cases and controls were collected prospectively for high resolution genetic a nalysis targeting 11 separate HLA loci. Statistical significance was set at 0.10 a priori to determine the association between HLA genotype and pseudotumour formation, given the small sample size. Using a previously-reported ALVAL classification, the majority of pseudotumour-positive caseswere found to have intermediate-grade group 2 (n = 10; 63%) or group 3 (n = 4; 25%) histological findings. Two further patients (13%) had high-grade group 4 lesions. HLA-DQB1*05:03:01 (p = 0.0676) and HLA-DRB1*14:54:01 (p = 0.0676) alleles were significantly associated with a higher risk of pseudotumour formation, while HLA-DQA1*03:01:01 (p = 0.0240), HLA-DRB1*04:04:01 (p = 0.0453), HLA-C*01:02:01 (p = 0.0453), and HLA-B*27:05:02 (p = 0.0855) were noted to confer risk reduction. These findings confirm the association between specific HLA genotypes and the risk of pseudotumour development around MoM hip resurfacings. Specifically, the two 'at risk' alleles (DQB1*05:03:01 and DRB1*14:54:01) may hold clinical value in preoperative screening and prospective surgical decision-making.

International primary knee arthroplasty registry review: findings from current reports.

INTRODUCTION: International joint registries provide high volumes of information in relation to the performance of total knee arthroplasty on a global scale. Distillation of this data can be challenging, particularly with the establishment of more arthroplasty registries on a yearly basis. We therefore aim to present key information from these registries in relation to primary total knee arthroplasty. The specific questions of interest include: Which fixation type is superior in TKA? Does the level of constraint impact on clinical performance? How do partial knee replacements perform in the registries? Does patellar resurfacing lead to superior results? Are there any specific implants which perform particularly well or poorly? METHODS: A comprehensive review of the major English-speaking knee arthroplasty registries across the globe was performed. Given the expanding large number of registries worldwide, it was not possible to perform a comprehensive review of all registries and so, a detailed review of the major English-speaking knee arthroplasty registries was included. Key trends and developments in implant performance were identified and presented in the current article. RESULTS: Total knee replacements have lower revision rates than both unicompartmental and patellofemoral joint replacement procedures. Patellofemoral joint replacements have the highest failure rate of all knee replacement procedures. Cruciate-Retaining (CR) TKR designs have superior outcomes to Posterior-Stabilized (PS) designs across all registries. Patellar resurfacing appears to confer an advantage over non-resurfaced patellas in primary TKR. CONCLUSION: We present current global trends in the utility and performance of TKA based on data from English-speaking arthroplasty registries.

Highly Crosslinked Polyethylene Liner Thickness Does Not Influence Survival in Primary Total Hip Arthroplasty After Mean Follow-Up of 13 Years: A Study of 2,565 Hips With a Single Design Liner.

BACKGROUND: Concerns remain that thinner highly crosslinked polyethylene (HXLPE) liners in modern total hip arthroplasty (THA) may lead to premature liner-related failures or revision. The aim of this study was to evaluate the effect of liner thickness on survival and revision rates of HXLPE in primary THA after more than 10 years. METHODS: We retrospectively identified 2,565 primary THAs using HXLPE with a mean follow-up of 13 years (range, 11 to 19). Patients were grouped for each mm of polyethylene thickness. Liner thickness varied from 4.9 to 12.7 mm, with one third measuring less than 6 mm. Primary outcomes were reoperation, all-cause revision, and liner-related revision. RESULTS: The reoperation rate was 7.3%, the all-cause revision rate was 5.6%, and the liner-related revision rate was 0.04%. There was no significant difference in all-cause revision when stratified by liner thickness (P = .286) and liner thickness was not associated with liner-related revision (n = 1). There was a statistically, but not clinically significant difference in mean liner thickness for the cohort that underwent reoperation (7.09 versus 6.89 mm, P = .01) and all-cause revision (7.16 versus 6.89 mm, P = .031). CONCLUSION: In our cohort, liner thickness was not associated with all-cause revision-free survival, and there was no clinically significant difference in liner thickness between those patients who did require a reoperation or all-cause revision, and those who did not. There was only 1 liner-related failure in the entire cohort. Our results indicate that using thinner HXLPE liners to maximize femoral head size in THA is a safe practice that does not lead to increased revision rates or liner failure at a mean 13-year follow-up.

International primary hip arthroplasty registry review: findings from current reports.

We present key information from international registries in relation to primary total hip arthroplasty. The specific questions of interest include which bearings are superior in total hip arthroplasty (THA), which fixation types are optimal, do any specific implants perform better than others, and what is the latest update in the hip fracture setting? This is a comprehensive review of the major English-speaking hip arthroplasty registries across the globe. Key trends and developments in implant performance are identified and presented in the current article. Key points from review of all registries confirm that ceramic-on-polyethylene and metal-on-polyethylene continue to be the commonest bearings. The use of cemented femoral stems is increasing across most regions. Hybrid fixation is now the commonest fixation method in the UK for the first time in registry history. Uncemented femoral stems have a higher early revision rate for periprosthetic fracture than cemented stems across most regions. Dual mobility (DM) bearings are increasing in use and show higher early revision rates than unipolar bearings-they tend to be used for more complex indications (fracture/tumor/revision) and show similar revision rates to unipolar bearings when used exclusively in primary elective THA for osteoarthritis. We present current trends in THA based on current registry data from across the globe. Clinical signals of concern are emerging for THA uncemented femoral stem fixation and DM bearings in specific clinical contexts. These signals should be monitored across the literature in order to reduce the overall revision burden.

Thin highly cross-linked polyethylene liners combined with large femoral heads in primary total hip arthroplasty show excellent survival and low wear rates at a mean follow-up of 12.8 years.

AIMS: Several short- and mid-term studies have shown minimal liner wear of highly cross-linked polyethylene (HXLPE) in total hip arthroplasty (THA), but the safety of using thinner HXLPE liners to maximize femoral head size remains uncertain. The objective of this study was to analyze clinical survival and radiological wear rates of patients with HXLPE liners, a 36 mm femoral head, and a small acetabular component with a minimum of ten years' follow-up. METHODS: We retrospectively identified 55 patients who underwent primary THA performed at a single centre, using HXLPE liners with 36 mm cobalt-chrome heads in acetabular components with an outer diameter of 52 mm or smaller. Patient demographic details, implant details, death, and all-cause revisions were recorded. Cox regression and Kaplan-Meier survival was used to determine all-cause and liner-specific revision. Of these 55 patients, 22 had a minimum radiological follow-up of seven years and were assessed radiologically for linear and volumetric wear. RESULTS: Overall survival rate for all-cause revision was 94.5% (95% confidence interval (CI) 81.7% to 97.2%) at a mean follow-up of 12.8 years (10.9 to 18.7). Three patients were revised, none for liner wear, fracture, or dissociation. A total of 22 patients were included in the radiological analysis (mean follow-up 9.9 years (7.5 to 13.7)). Mean linear liner wear was 0.085 mm (95% CI -0.086 to 0.257) and the volumetric wear rate was 11.097 mm3/year (95% CI -6.5 to 28.7). CONCLUSION: Using HXLPE liners with 36 mm heads in 52 mm acetabular components or smaller is safe, with excellent survival and low rates of linear and volumetric wear at medium-term follow-up. Patients did not require revision surgery for liner complications such as fracture, dissociation, or wear. Our results suggest that the advantages of using larger heads outweigh the potential risks of using thin HXLPE liners.Cite this article: Bone Joint J 2023;105-B(1):29-34.

Survivorship of 500 Cementless Total Knee Arthroplasties in Patients Under 55 Years of Age.

BACKGROUND: With respect to survivorship following total knee arthroplasty (TKA), joint registries consistently demonstrate higher revision rates for both genders in those aged less than 55 years. The present study analyzed the survivorship of 500 cementless TKAs performed in this age group in a high-volume primary joint unit where cementless TKA has traditionally been used for the majority of patients. METHODS: This was a retrospective review of 500 consecutive TKAs performed in patients aged less than 55 years between March 1994 and April 2017. The primary outcome measures for the study were survivorship and all-cause revisions. Secondary outcome measures included nonrevision procedures, clinical, functional, and radiological outcomes. RESULTS: An all-cause survival rate of 98.4% and an aseptic survival rate of 99.2% at a median time of 10.7 years (interquartile range 7.3-14.9, range 0.2-27.7) were found. Four patents were revised for infection, 2 for stiffness, 1 for aseptic loosening of the tibial component, and 1 for a patella that was resurfaced for anterior knee pain. Thirty four patients (6.8%) had a nonrevision procedure with manipulation under anesthetic accounting for 27. On a multivariate analysis, preoperative range of motion and female gender were negatively associated with postoperative range of motion (P < .001 and P = .003, respectively). Sixty seven patients (17.3%) had radioluscent lines and on a multivariate analysis, there were no significant predictors of radiolucent lines. CONCLUSION: Cementless TKA in the young patient can achieve excellent clinical and functional outcomes. At a median of 10.7 years, aseptic revision rates are exceptionally low at 0.8% for the entire cohort.