Purpose:This study aimed to evaluate the pharmacokinetic (PK) drug-drug interactions (DDIs) of DA-8010 with clarithromycin or rifampicin, and to assess the influence of cytochrome P450 (CYP) 2D6 phenotype on the extent of these interactions. Methods:An open-label, fixed-sequence, three-period crossover study was conducted in healthy participants. Participants received a single dose of DA-8010 5 mg alone on Day 1 (Period 1); clarithromycin 500 mg twice daily from Day 6 to 11, with a concomitant single dose of DA-8010 5 mg on Day 10 (Period 2); and rifampicin 600 mg once daily from Day 16 to 25, with a concomitant single dose of DA-8010 5 mg on Day 25 (Period 3). Each treatment period was separated by a five-day washout. Serial blood samples for PK assessments of DA-8010 were collected up to 48 h post-dose. CYP2D6 genotyping was performed retrospectively, and phenotypes were assigned based on activity score. Results:Sixteen participants completed the study: eleven were classified as CYP2D6 extensive metabolizers (EMs) and five as CYP2D6 intermediate metabolizers (IMs). Co-administration of DA-8010 with clarithromycin had no significant effect on the PKs of DA-8010. In contrast, co-administration with rifampicin reduced the systemic exposure of DA-8010 by approximately 50% compared with DA-8010 alone. Across all treatment conditions, DA-8010 exposure was approximately two-fold higher in IMs than in EMs. Conclusion:DA-8010 showed no clinically meaningful PK interaction with clarithromycin, while rifampicin significantly reduced DA-8010 exposure. Although the CYP2D6 phenotype affected overall DA-8010 exposure, it did not alter the extent of the PK interaction observed with clarithromycin or rifampicin.

Low-dose combination therapies are recommended when monotherapy fails to control hypertension. This exploratory study aimed to compare the pharmacokinetics (PK) of 2 fixed-dose combinations (FDCs) of telmisartan, amlodipine, and chlorthalidone: half-dose test FDC (20/2.5/6.25 mg) and a conventional-dose reference FDC (40/5/12.5 mg). A randomized, open-label, single-dose, parallel-group study was conducted in healthy participants. Each participant received a single oral dose of either the test or reference FDC. Serial blood samples for telmisartan, amlodipine, and chlorthalidone were collected up to 72 hours post-dose, and PK parameters were calculated using noncompartmental analysis. The mean maximum plasma concentrations (Cmax) of telmisartan, amlodipine, and chlorthalidone were 41.34 and 155.75 μg/L, 1.74 and 4.42 μg/L, and 39.36 and 104.86 μg/L for the test and reference FDCs, respectively. The mean area under the concentration-time curves to the last measurable time point (AUClast) were 659.93 and 1,673.51 h·μg/L for telmisartan, 57.98 and 128.75 h·μg/L for amlodipine, and 831.73 and 1,826.86 h·μg/L for chlorthalidone. The test FDC demonstrated systemic exposure levels ranging from 0.27- to 0.39-fold for telmisartan, 0.39- to 0.44-fold for amlodipine, and 0.38- to 0.46-fold for chlorthalidone, compared to the reference FDC. In conclusion, the PK profiles of the half-dose test FDC were consistent with the known characteristics of the individual components. These provide the first PK data for this half-dose test FDC and may support its potential as an alternative treatment option for hypertension. However, as this was an exploratory study, the results should be interpreted with caution. Trial Registration:Clinical Research Information Service Identifier: KCT0010166.

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder often associated with obesity and elevated cardiovascular risks. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have become integral to T2DM management due to their clinical benefits of glucose regulation and weight loss. However, their subcutaneous administration presents challenges to patient adherence, limiting their widespread use. Oral semaglutide (Rybelsus®), the first oral GLP-1 RA approved for T2DM, addresses these challenges through an innovative co-formulation with sodium N-(8-[2-hydroxybenzoyl] amino) caprylate, which enhances gastric absorption and stability. This review provides a comprehensive overview of the clinical development of oral semaglutide, with a focus on early-phase trials. Phase 1 studies investigated pharmacokinetics, pharmacodynamics, safety, and dose-response relationships, demonstrating a dose-dependent reduction in hemoglobin A1c (HbA1c) and body weight with an acceptable safety profile. Additionally, pharmacological evaluations of interactions with food, dosing condition, disease states, and concomitant medications supported the determination of an optimal dosing regimen for further clinical studies. Phase 2 dose-finding trials confirmed significant HbA1c and weight reductions comparable to subcutaneous semaglutide, which guided dose selection for phase 3 trials. Phase 3 trials, including the Peptide InnOvatioN for Early diabEtes tReatment program, demonstrated significant reductions in HbA1c, weight loss, and cardiovascular safety, positioning oral semaglutide as a transformative option in diabetes care. The study highlights comprehensive clinical strategies and provides an insight into the future development of oral GLP-1 RAs and other oral peptide drugs.

Optimal treatment for iliopsoas tendinitis (IPTs) after total hip arthroplasty (THA) with cup malposition is controversial between iliopsoas release alone and cup revision especially in young active patients. Moreover, arthroscopic iliopsoas tendon (IPT) release in these patients has been rarely described and mid-term effect of this on THA longevity and recurrence of groin pain is unclear. We performed arthroscopic IPT release for IPTs after THA and report mid-term outcome in two young patients with acetabular cup malposition. Two patients visited the hospital for groin pain which started early after THA. Both patients showed non-specific findings on physical examination and no evidence of infection on laboratory tests. X-ray and CT scans showed reduced acetabular component anteversion angle and anterior cup prominence more than 16 mm. As therapeutic diagnosis, ultrasonography-guided lidocaine injection with steroid into IPT sheath was performed. Initially, groin pain improved, but after a few months, it worsened in both patients. Therefore, we performed arthroscopic IPT release under spinal anesthesia. Arthroscopy revealed synovitis with fibrous tissues around IPT and various lesions related to the implants after THA. IPT tenotomy and debridement with biopsy were performed and histopathology showed chronic inflammation with synovial hyperplasia. Both patient were encouraged to start walking immediately after surgery and returned to complete daily life early after surgery without recurrence of groin pain and any implant-related problems at 9 years postoperatively. Arthroscopic IPT release showed excellent mid-term outcome without recurrence of groin pain and implant-related problems in those with cup malposition.

Hyaluronidase has been used as an adjuvant to facilitate subcutaneous drug delivery by degrading hyaluronic acid, a viscoelastic barrier in subcutaneous tissue. However, traditional animal-derived hyaluronidases raise safety concerns, including risk of anaphylaxis and zoonoses. This study aimed to evaluate the safety, tolerability, and pharmacokinetics of ALT-BB4, a novel recombinant hyaluronidase derived from human hyaluronidase PH20, in healthy adults. This first-in-human, multicenter, randomized, double-blinded, placebo-controlled phase 1 study included 244 participants who received single intradermal or subcutaneous injections of ALT-BB4 or placebo. The study was conducted in three parts: part I assessed drug allergy reactions, part II-A evaluated pharmacokinetics, and part II-B assessed safety and tolerability. Intradermal injection of ALT-BB4 exhibited a low incidence of drug allergy reactions (0.4

AbstractFexuprazan, a novel potassium‐competitive acid blocker, is expected to be used for the prevention of nonsteroidal anti‐inflammatory drugs (NSAIDs) induced ulcer. This study aimed to evaluate pharmacokinetic (PK) interactions between fexuprazan and NSAIDs in healthy subjects. A randomized, open‐label, multicenter, six‐sequence, one‐way crossover study was conducted in healthy male subjects. Subjects randomly received one of the study drugs (fexuprazan 40 mg BID, celecoxib 200 mg BID, naproxen 500 mg BID, or meloxicam 15 mg QD) for 5 or 7 days in the first period followed by the combination of fexuprazan and one of NSAIDs for the same days and the perpetrator additionally administered for 1–2 days in the second period. Serial blood samples for PK analysis were collected until 48‐ or 72‐h post‐dose at steady state. PK parameters including maximum plasma concentration at steady state (Cmax,ss) and area under plasma concentration–time curve over dosing interval at steady state (AUCτ,ss) were compared between monotherapy and combination therapy. The PKs of NSAIDs were not significantly altered by fexuprazan. For fexuprazan, differences in PK parameters (22% in Cmax, 19% in AUCτ,ss) were observed when co‐administered with naproxen, but not clinically significant. The geometric mean ratio (90% confidence interval) of combination therapy to monotherapy for Cmax,ss and AUCτ,ss was 1.22 (1.02–1.46) and 1.19 (1.00–1.43), respectively. There were no significant changes in the systemic exposure of fexuprazan by celecoxib and meloxicam. Fexuprazan and NSAIDs did not show clinically meaningful PK interactions.

Although mesenchymal stem cells (MSCs) insertion has gained recent attention as a joint-preserving procedure, no study has conducted direct intralesional implantation of human umbilical cord-derived MSCs (hUCMSCs) in patients with ONFH. This is a protocol for a phase 1 clinical trial designed to assess the safety and exploratory efficacy of human umbilical cord-derived osteoblasts (hUC-Os), osteogenic differentiation-induced cells from hUCMSCs, in patients with early-stage ONFH. Nine patients with Association Research Circulation Osseous (ARCO) stage 1 or 2 will be assigned to a low-dose (1 × 107 hUC-O cells, n = 3), medium-dose (2 × 107 cells, n = 3), and high-dose group (4 × 107 cells, n = 3) in the order of their arrival at the facility, and, depending on the occurrence of dose-limiting toxicity, up to 18 patients can be enrolled by applying the 3 + 3 escalation method. We will perform hUC-O (CF-M801) transplantation combined with core decompression and follow-up for 12 weeks according to the study protocol. Safety will be determined through adverse event assessment, laboratory tests including a panel reactive antibody test, vital sign assessment, physical examination, and electrocardiogram. Efficacy will be explored through the change in pain visual analog scale, Harris hip score, Western Ontario and McMaster Universities Osteoarthritis Index, ARCO stage, and also size and location of necrotic lesion according to Japanese Investigation Committee classification before and after the procedure. Joint preservation is important, particularly in younger, active patients with ONFH. Confirmation of the safety and efficacy of hUC-Os will lead to a further strategy to preserve joints for those suffering from ONFH and improve our current knowledge of cell therapy.

Abstract Vutiglabridin, which affects the pharmacokinetics (PKs) of food, is currently under clinical development for the treatment of obesity. This study aimed to evaluate the effects of low‐ and high‐fat meals on PKs of vutiglabridin in healthy male subjects. A randomized, open‐label, single‐dose, three‐period, six‐sequence crossover study was conducted. The subjects received a single oral dose of vutiglabridin 480 mg in a fasted state, 30 min after the intake of a low‐fat meal (total 500–600 kcal, fat content 100–125 kcal) and high‐fat meal (total 800–1000 kcal, fat content 500–600 kcal), with a 21‐day washout period. Geometric mean ratios (GMRs) and 90% confidence intervals (CIs) for maximum plasma concentration (Cmax) and area under the plasma concentration‐time curve to the last measurable timepoint (AUClast) were calculated. After intake of low‐ and high‐fat meals, systemic exposure to vutiglabridin was increased, and the time to reach Cmax (Tmax) was delayed compared to that in the fasted state. The GMRs (90% CIs) of low‐fat meal to fasted state for Cmax and AUClast were 2.14 (1.76–2.60) and 2.15 (1.92–2.42), respectively, and those of high‐fat meal to fasted state were 3.07 (2.53–3.72) and 3.00 (2.67–3.37), respectively. The median Tmax was delayed by 1.5 h in both fed states compared with that in the fasted state. The study drug was well‐tolerated after administration in both the fed and fasted states. Food ingestion substantially increased the extent of oral vutiglabridin absorption in healthy subjects, and this enhancement increased with the fat content of the meal.

Aim: To investigate the possible effect of haemodialysis (HD) on the pharmacokinetic (PK) and pharmacodynamic (PD) characteristics of evogliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor.Methods: A single-dose, open-label, parallel-group study of eight end-stage renal disease (ESRD) patients and eight matched healthy subjects was conducted. ESRD patients received a single oral dose of evogliptin 5 mg after and before HD with a 2-week washout between each dose, and healthy subjects received a single oral dose of evogliptin 5 mg. Serial blood, dialysate, and urine samples were collected to assess the PK and PD profiles of evogliptin. To compare PK parameters before and after HD, geometric mean ratios (GMRs) and 90% confidence intervals (CIs) were calculated.Results: The GMRs for the maximum concentration and area under the concentration-time curve from time 0 to the last measurable timepoint (AUC(last)) of evogliptin when administered before HD compared with after HD were 0.7293 (90% CI 0.6171-0.8620) and 0.9480 (90% CI 0.8162-1.1010), respectively. The maximum DPP-4 inhibitory effect, area under the DPP-4 inhibitory effect-time curve, and time duration of more than 80% DPP-4 inhibition were comparable when evogliptin was administered before and after HD. Compared with healthy subjects, the mean AUC(last) of evogliptin was approximately 1.4-fold greater in ESRD patients, but the difference is unlikely to affect the safety and efficacy of evogliptin.Conclusion: The effect of HD on the PK and PD characteristics of evogliptin was not clinically significant; therefore, dose adjustment according to HD status is not necessary.

The atypical femoral fracture (AFF) has been attracting significant attention because of its increasing incidence; additionally, its treatment is challenging from biological and mechanical aspects. Although surgery is often required to manage complete AFFs, clear guidelines for the surgical treatment of AFFs are currently sparse. We reviewed and described the surgical treatment of AFFs and the surveillance of the contralateral femur. For complete AFFs, cephalomedullary intramedullary nailing spanning the entire length of the femur can be used. Various surgical techniques to overcome the femoral bowing common in AFFs include a lateral entry point, external rotation of the nail, and the use of a nail with a small radius of curvature, or a contralateral nail. In the case of a narrow medullary canal, severe femoral bowing, or pre-existing implants, plate fixation may be considered as an alternative. For incomplete AFFs, prophylactic fixation depends on several risk factors, such as a subtrochanteric location, presence of a radiolucent line, functional pain, and condition of the contralateral femur; the same surgical principles as those in complete AFFs can be applied. Finally, once AFF is diagnosed, clinicians should recognize the increased risk of contralateral AFFs, and close surveillance of the contralateral femur is recommended.

Background:The Harris-Galante (HG) prosthesis is a first-generation, cementless total hip arthroplasty (THA) prosthesis. Considering the recent increase in the demand for THA in young patients and their life expectancy, a study with a follow-up duration of longer than 20 years in a young population is needed. Therefore, we evaluated the long-term clinical and radiographic results after cementless THA using the HG prosthesis in patients younger than 50 years.Methods:A total of 61 THAs performed using the HG with a minimum follow-up of 10 years were included. There were 38 men and 11 women with an average age of 46 years and the mean follow-up duration was 22 years. Clinical evaluation included modified Harris Hip Score (HHS) and radiographic analysis consisted of cup inclination, anteversion angle, component stability, osteolysis, liner wear rate, wear-through, liner dissociation, and heterotopic ossification. Complications included recurrent dislocation, periprosthetic femoral fracture, and periprosthetic joint infection. Survivorship analysis included cup and stem revision for aseptic loosening, as well as any revision.Results:The HHS improved from 46.5 preoperatively to 81.8 postoperatively (p < 0.001). The average linear wear rate was 0.36 mm/yr. A total of 34 hips (56%) were revised: stem revision in 10 (16.4%), cup revision in 9 (14.8%), exchange limited to bearing surface in 8 (13.1%), and revision of all components in 7 (11.5%). Estimated survivorship at 34 years postoperatively was 90.9% for cup revision for aseptic loosening, 80.5% for stem revision for aseptic loosening, and 22.1% for any revision.Conclusions:THA using the HG prosthesis showed satisfactory estimated survivorship of the acetabular and femoral components at 34 years postoperatively with good clinical outcomes. Bearing-related problems, such as osteolysis and liner dissociation, accounted for 56% of revision operations and were concerns in patients younger than 50 years.

Fetal tachycardia (FT) is a rare disorder and is associated with significant mortality of fetus. Digoxin is one of the antiarrhythmic agents used to treat FT via transplacental therapy. In this report, we describe a therapeutic drug monitoring (TDM) case of digoxin during the treatment of FT. A 40-year-old woman, gravida 2 para 1, hospitalized to control FT as the fetal heart rate (FHR) showed over 200 bpm on ultrasonography at 29 weeks of gestation. She did not have any medical or medication history and showed normal electrolytes level on clinical laboratory test results. For the treatment of FT loading and maintenance dose of intravenous digoxin (loading dose: 0.6 mg; maintenance dose: 0.3 mg every 8 hours) were administered. To monitor the efficacy and safety of the treatment, TDM was conducted with a target maternal serum trough digoxin concentration of 1.0 to 2.0 ng/mL, as well as ultrasonography and maternal electrocardiogram. The observed digoxin serum concentrations were 0.67, 0.83, and 1.05 ng/mL after 1, 2, and 5 days after the initiation of digoxin therapy, respectively. Although the serum digoxin concentrations reached the target range, the FHR did not improve. Therefore, digoxin was discontinued, and oral flecainide therapy was started. The FHR adjusted to the normal range within 2 days from changing treatment and remained stable. TDM of digoxin along with the monitoring of clinical responses can give valuable information for decision-making during the treatment FT.

Background: Abnormal lipid metabolism may play an important role in the development of nontraumatic osteonecrosis of the femoral head (ON). By comparing lipid biomarkers in patients with ON and osteoarthritis (OA) after propensity score matching, we sought to reveal (1) common lipid biomarkers that are abnormal in ON regardless of the etiology and (2) specific lipid biomarkers associated with ON according to the etiology. Methods: Among 2,268 patients who underwent primary THA, 1,021 patients were eligible for this study. According to the Association Research Circulation Osseous criteria, ON was classified as either idiopathic (n = 230), alcohol-associated (n = 293), or glucocorticoid-associated ON (n = 132). Most common cause of OA was hip dysplasia in 106 patients (47%). We investigated patient lipid profiles by assessing total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TGs), apolipoprotein (Apo) A1 and B, lipoprotein (a) levels and ApoB/A1 ratio. Since age and body mass index affect the lipid profile, we performed propensity score matching to select 304 patients for final analysis and compared lipid profiles between the ON and OA groups. We also compared biomarkers between the ON subgroups and the OA group. Results: Overall, the ON group showed lower HDL-C (p < 0.001), higher TGs (p = 0.001) levels and higher ApoB/A1 ratio (p = 0.003). Idiopathic ON patients demonstrated lower HDL-C (p = 0.032), higher TGs (p = 0.016), ApoB (p = 0.024) levels and ApoB/A1 ratio (p = 0.008). The alcohol-associated ON subgroup showed lower HDL-C (p < 0.001), higher TGs (p = 0.010) levels and ApoB/A1 ratio (p = 0.030). Finally, the steroid-associated ON subgroup demonstrated lower HDL-C (p = 0.003), higher TGs (p = 0.039), lower TC (p = 0.022), LDL-C (p = 0.021), and ApoA1 (p = 0.004) levels. Conclusions: Higher TGs and lower HDL-C levels were associated with nontraumatic ON regardless of the etiology. Additionally, idiopathic ON was associated with higher ApoB levels and ApoB/A1 ratio. Alcohol-associated ON was related to higher ApoB/A1 ratio, and steroid-associated ON paired with decreased TC, LDL-C, and ApoA1 levels. Our findings may support future efforts for prevention and management of nontraumatic ON. Level of Evidence: Diagnostic Level III.

The optimal technique for plate fixation to treat type B and C periprosthetic femoral fractures (PFFs) is unclear. The purpose of this study is to evaluate the radiographic results of inner-side-out limited contact dynamic compression plate (LC-DCP) to treat PFFs during or after total hip arthroplasty (THA). This retrospective study comprised of four men and six women with an average age of 64.7 years who underwent open reduction and internal fixation with an inner-side-out LC-DCP technique to treat PFFs; the reduction was maintained preliminary with the use of contoured plate and cables, and the grooves on the undersurface of LC-DCP for limited contact was used to hold and prevent the cables from slippage during tightening the cables. There were five intraoperative and five postoperative PFFs after THA. According to the Vancouver classification, the intraoperative PFFs included type B2 in two, B3 in one and C3 in two patients while postoperative PFFs were categorized into type B1 in one, type B2 in two and type C in two patients. The mean follow-up duration was 5.9 years (range 1–10.4). We evaluated radiographic union and complications after index operation. All patients demonstrated radiographic bone union at an average follow-up duration of 4.4 months (range 3–8). Two patients showed stem subsidence after revision THA and one patient demonstrated a subsequent peri-implant fracture around the distal end of plate after union of the initial PPF; one patient underwent re-revision THA for stem loosening while another patient went through refixation for the peri-implant fracture. There was no nonunion, infection, nerve injury, or dislocation. The inner-side-out LC-DCP technique showed satisfactory radiographic outcome. In certain situations where locking plates are not available, this technique might be a useful alternative for treating type B and C PFFs.

Introduction: Coccyx fracture usually is a low-energy trauma caused by a backward fall onto a slippery floor of ice. The exact epidemiology of the coccyx fracture is not known. Moreover, the effects of seasonality and weather on the fracture incidence have not been reported. The purpose of this study was to evaluate the annual incidence, gender-preponderance, age-distribution, seasonal variation and climatic risk factors of the coccyx fracture. Methods: We identified coccyx fractures, which occurred in South Korea from 2010 to 2018, using nationwide data of Korean Health Insurance Review and Assessment Service (HIRA). International Classification of Diseases-10th Revision (ICD-10) code 5322 was used for the identification. Annual incidence of the coccyx fracture was calculated, and the fractures were correlated with gender, age, month of diagnosis and climatic factors. Results: A total of 238,906 patients were diagnosed with coccyx fracture with an average of 26,545 patients at year. Male to female ratio was 1:2.6. The annual incidence of coccyx fracture was 119.75/100,000 persons in 2018; 33.44/100,000 in male and 86.30/100,000 in female. The incidence rate was the highest at puberty (age of 10-14 years) in male, and at menopause (age of 50-54 years) in female. The incidence was frequent in winter followed by summer. The incidence of coccyx fracture was negatively correlated with the temperature (Pearson correlation factor= -0.67, P<0.01) in winter, while it was positively correlated with the temperature in summer (Pearson correlation coefficient = 0.66, p<0.01). In generalized linear model, old age, female gender, recent year, summer and winter, low temperature and high amount of precipitation appeared as risk factors for coccyx fracture. Conclusions: The epidemiologic patterns of coccyx fracture were comparable to other osteoporotic fractures. Findings of our study can be used for epidemiological awareness and prevention campaigns of coccyx fracture. (C) 2020 Elsevier Ltd. All rights reserved.

BACKGROUND There are few studies in the literature comparing the clinical outcomes and radiographic results of proximal femoral nail (PFN) and proximal femoral nail antirotation (PFNA) for pertrochanteric femoral fracture (PFF) in elderly patients. AIM To evaluate both clinical and radiographic outcomes after fixation with PFN and PFNA in an elderly patient population. METHODS One hundred fifty-eight patients older than 65 years with PFF who underwent fixation with either PFN or PFNA were included. Seventy-three patients underwent fixation with PFN, whereas 85 were fixed with PFNA. The mean follow-up was 2.4 years (range, 1-7 years). Clinical outcome was measured in terms of operation time, postoperative function at each follow-up visit, and mortality within one year. Radiographic evaluation included reduction quality after surgery, Cleveland Index, tip-apex distance (TAD), union rate, time to union, and sliding distance of the screw or blade. Complications including nonunion, screw cutout, infection, osteonecrosis of the femoral head, and implant breakage were also investigated. RESULTS Postoperative function was more satisfactory in patients who underwent PFNA than in those who underwent PFN (P = 0.033). Radiologically, the sliding difference was greater in PFN than in PFNA patients (6.1 and 3.2 mm, respectively, P = 0.036). The rate of screw cutout was higher in the PFN group; eight for PFN (11.0%) and two for PFNA patients (2.4%, P = 0.027). There were no differences between the two groups in terms of operation time, mortality rate at one year after the operation, adequacy of reduction, Cleveland Index, TAD, union rate, time to union, nonunion, infection, osteonecrosis, or implant breakage. CONCLUSION Elderly patients with PFF who underwent PFNA using a helical blade demonstrated better clinical and radiographic outcomes as measured by clinical score and sliding distance compared with patients who underwent PFN.

BACKGROUND Optimal treatment for iliopsoas tendinitis after total hip arthroplasty (THA) with cup malposition, iliopsoas release alone or with cup revision, is controversial, particularly in young, active patients. Moreover, arthroscopic iliopsoas tendon (IPT) release in these patients has been rarely described, and midterm effects of this procedure on THA longevity and groin pain recurrence remain unclear. We performed arthroscopic IPT release after THA and report midterm outcomes in two young patients with acetabular cup malposition. CASE SUMMARY In the two patients, groin pain started early after THA. Physical examination revealed nonspecific findings, and laboratory tests showed no evidence of infection. Radiography and computed tomography showed reduced acetabular component anteversion angle and anterior cup prominence of more than 16 mm. For therapeutic diagnosis, ultrasonography-guided lidocaine with steroid was injected into the IPT sheath. In both patients, groin pain improved initially but worsened after a few months. Therefore, the patients underwent arthroscopic IPT release under spinal anesthesia. Arthroscopy revealed synovitis with fibrous tissues around the IPT and various lesions related to the implants after THA. IPT tenotomy and debridement with biopsy were performed; histopathologic studies showed chronic inflammation with synovial hyperplasia. Both patients were encouraged to start walking immediately after surgery, and they returned to complete daily function early after surgery. They experienced no recurrence of groin pain or any implant-related problems 5 years postoperatively. CONCLUSION Arthroscopic IPT release for cup malposition produced excellent midterm outcomes without recurrence of groin pain and implant-related problems.

Background Reconstruction intramedullary nail spanning the whole length of the femur has been the gold standard treatment for complete atypical diaphyseal fractures of the femur (ADF). However, in cases of incomplete ADF combined with severe bowing, this approach might have complications and lead to iatrogenic complete fracture. We report two cases of incomplete ADF with severe bowing using a precontoured plate (PCP) after rapid prototyping (RP) of the deformed femurs with three‐dimensional printing (3DP) technology. Case presentation Two patients presented with gradually worsening thigh pain, especially during walking. The patients had been using bisphosphonates for 4 and 10 years, respectively. Radiography showed an incomplete fracture in the lateral cortex of the right femur shaft. The lateral bowing angles measured in the affected femurs were 15° and 14°, and the anterior bowing angles were 20° and 16°, respectively. In bone scans, both patients showed hot uptake in the right mid‐shaft of the femur. Preoperatively, the affected femur of the patient was reconstructed by 3DP RP using CT, and the plate was bent to the shape of the bone model. The ADF was fixed with a PCP using the minimally invasive plate osteosynthesis technique. Both patients were encouraged to start full weight‐bearing and return to their preinjury activity level in daily life immediately after surgery. At 2 years postoperatively, radiography showed healing of the fracture site without recurrence of thigh pain and implant‐related problems. Conclusion Although intramedullary nailing is the standard surgical treatment for complete ADF, PCP using 3DP RP could be an effective treatment option for incomplete ADF with severely curved femur.