A case of non-esophageal eosinophilic gastrointestinal disease diagnosed by mucosal incision-assisted biopsy.

A 46-year-old woman presented at our hospital with anorexia, vomiting, and diarrhea. Blood tests indicated markedly increased eosinophil counts, and esophagogastroduodenoscopy revealed slight erythema in the gastric body. Computed tomography showed edematous thickening of the stomach and small intestinal walls and peritonitis. Thus, eosinophilic gastrointestinal disease was suspected. Endoscopic biopsies from the esophagus, stomach, and duodenum were collected, but no significant increases in eosinophil counts were observed. Little ascites effusion was detected and puncture cytology was difficult to perform. Thus, a sample of the muscularis propria layer was obtained by mucosal incision-assisted biopsy. Histopathological examination of the biopsy revealed significant eosinophilic infiltration within the muscularis propria layer of the stomach, confirming the diagnosis of non-eosinophilic esophagitis eosinophilic gastrointestinal disease. The patient was treated with a leukotriene receptor antagonist and prednisolone, and her clinical symptoms and gastrointestinal wall thickening rapidly improved. The Japanese diagnostic guideline for non-eosinophilic esophagitis eosinophilic gastrointestinal disease requires endoscopic biopsy or eosinophilic infiltration of ascites fluid. When diagnosis is difficult using conventional methods, as in this case, mucosal incision-assisted biopsy is useful as a next step.

Postmarketing surveillance of nivolumab plus ipilimumab combination therapy in Japanese patients with unresectable malignant melanoma.

Although malignant melanoma is relatively rare in Japan, it is often diagnosed at a later stage than in Western countries. Nivolumab and ipilimumab are immune checkpoint inhibitors targeting programmed death 1 and cytotoxic T-lymphocyte-associated protein 4, respectively. Owing to their complementary anticancer effects, nivolumab and ipilimumab combination therapy (N + I) has been studied and approved for treating malignant melanoma in various countries including Japan. Real-world postmarketing surveillance was implemented to record treatment-related adverse events (TRAEs) in patients treated with N + I following its approval in Japan. Patients were eligible for registration if they had unresectable malignant melanoma and started N + I between September 2018 and August 2019. The observation period was 13 weeks from starting N + I. Only safety information was collected and evaluated. The final case report form lock was March 2021. Overall, 173 patients (median age, 66.0 years; performance status 0-1, 88.4%; skin: 53.2%; mucosal: 32.4%) were eligible for the analyses. Overall, 34.1% of patients completed 4 doses of N + I. N + I was discontinued by 63.0% (due to adverse events in 67.9% and disease progression/death in 22.9%). Any grade and grade ≥3 TRAEs were reported in 73.41% and 52.02%, respectively. TRAEs in ≥10 patients were hepatic function abnormal (any grade/grade ≥3: 23.12%/13.29%), pyrexia (10.40%/0.58%), diarrhea (9.25%/2.89%), rash (8.67%/0.58%), hypophysitis (5.78%/5.20%), interstitial lung disease (5.78%/2.89%), and liver disorder (5.78%/4.62%). TRAEs were classified as recovered (36.99% of patients), recovering (44.51%), unrecovered (13.29%), recovered with sequelae (2.31%), and death (1.73%). Overall, 24 of 34 patients (70.59%) with gastrointestinal-related and 53 of 65 (81.54%) liver-related TRAEs received treatment, such as a steroid with/without an immunosuppressant; most patients recovered within 1 to 2 months. In conclusion, this postmarketing surveillance of N + I in patients with unresectable malignant melanoma revealed no new safety concerns compared with results of prior studies. Immune-related TRAEs were generally manageable by appropriate treatment including a steroid.

The safety profile of nivolumab plus ipilimumab combination therapy in Japanese patients with renal cell carcinoma: results from post-marketing surveillance.

BACKGROUND: Nivolumab and ipilimumab combination therapy is approved in Japan for unresectable or metastatic renal cell carcinoma. Because the clinical trials supporting the approval of nivolumab and ipilimumab combination therapy included relatively few Japanese patients, post-marketing surveillance was implemented to collate further safety data for nivolumab and ipilimumab combination therapy. METHODS: Patients with unresectable or metastatic renal cell carcinoma who started nivolumab and ipilimumab combination therapy between September 2018 and December 2019 were registered in this post-marketing surveillance. The observation period was 13 weeks. Safety data included treatment-related adverse events with a particular emphasis on the gastrointestinal-related (colitis, enteritis, diarrhoea and gastrointestinal perforation) and liver-related (hepatic failure, hepatic function abnormal, hepatitis and cholangitis sclerosing) treatment-related adverse events that are listed in the risk management plan for nivolumab and ipilimumab combination therapy. RESULTS: Of the 203 patients registered, safety data were available for 159 (119 males/40 females) with a median age of 67 years (range 22-88). Seventy-one patients received nivolumab and ipilimumab combination therapy four times per usual clinical therapy, and 33 continued nivolumab monotherapy thereafter. Any-grade treatment-related adverse events were reported in 102 (64.2%) patients and grade ≥ 3 in 63 (39.6%). Hepatic function abnormalities (13.2%), rash (8.8%) and interstitial lung disease (7.5%) were the most common treatment-related adverse events. Five patients died following treatment-related adverse events. Gastrointestinal-related and liver-related treatment-related adverse events occurred in 10 (6.3%; four with grade ≥ 3 treatment-related adverse events) and 27 (17.0%; 19 with grade ≥ 3 treatment-related adverse events) patients, respectively. CONCLUSIONS: This post-marketing surveillance in patients with unresectable or metastatic renal cell carcinoma revealed a safety profile for nivolumab and ipilimumab combination therapy consistent with CheckMate 214. Furthermore, no new safety concerns were identified including gastrointestinal-related and liver-related treatment-related adverse events.

The Plastic Larval Body Color of the Pale Grass Blue Butterfly Zizeeria maha (Lepidoptera: Lycaenidae) in Response to the Host Plant Color: The Maternal Effect on Crypsis.

Many lepidopteran larvae show body color polyphenism, and their colors may be cryptic on the host plant leaves. To elucidate the effect of the host plant color on the plastic larval body color, we focused on the lycaenid butterfly Zizeeria maha, which shows various larval body colors ranging from green to red, even within a sibling group. We showed that oviposition was normally performed on both green and red leaves, despite a green preference and the fact that the larvae grew equally by consuming either green or red leaves. The number of red larvae decreased from the second instar stage to the fourth instar stage, demonstrating a stage-dependent variation. When the larvae were fed either green or red leaves across multiple generations of the lineages, the red larvae were significantly more abundant in the red leaf lineage than in the green leaf lineage. Moreover, the red-fed siblings showed a significantly higher red larval frequency than the green-fed siblings in the red-leaf lineage but not in the green-leaf lineage. These results suggest that, in this butterfly species, the plastic larval body color for crypsis may be affected not only by the color of the leaves that the larvae consume (single-generation effect) but also by the color of the leaves that their mothers consume (maternal effect), in addition to a stage-dependent color variation.

Infiltrative Erythemas and Nodules on a Unilateral Cheek Following Inappropriate Use of a Topical Steroid.

A 50-year-old Japanese woman referred to us with erythematous nodules on her left cheek. She had been treated with topical corticosteroids on her left cheek at a previous local clinic for 4 years. A skin biopsy specimen from a nodule showed perifolliculitis and folliculitis with a destruction of hair follicle without epidermal involvement. Based on the patient's history of the long-term topical corticosteroids and physical examination, we finally diagnosed this case as unilateral steroid-induced rosacea-like dermatitis (SIRD). She stopped topical steroid and was treated with topical application of benzoyl peroxide. One and a half year after starting the treatment, the nodules were flattened. Use of long-term and only unilateral application of topical corticosteroids probably resulted in unique clinical findings in our case. Given the broad clinical differential diagnosis, our case highlights the importance of appropriate application of topical steroids as well as histopathological analysis on any facial erythematous nodules.

Safety, efficacy and prognostic analyses of sunitinib in the post-marketing surveillance study of Japanese patients with gastrointestinal stromal tumor.

OBJECTIVE: This study was conducted to expand the sunitinib safety database in Japanese imatinib-resistant/-intolerant gastrointestinal stromal tumor patients. Retrospective analyses investigated common adverse events as potential prognostic markers. METHODS: Four hundred and seventy patients who received sunitinib between June 2008 and November 2009 were analyzed for safety, progression-free survival and overall survival; 386 for objective response rate; 88% received sunitinib on Schedule 4/2 starting at 50 mg/day. RESULTS: No unexpected safety issues occurred. Grade ≥ 3 adverse events occurred in 70%, most commonly thrombocytopenia (33%), neutropenia (22%) and leukopenia (15%). Objective response rate was 20% (95% confidence interval 16-24). Median progression-free survival was 22.4 weeks (95% confidence interval, 21.7-24.0). The overall survival rate at 24 weeks was 91% (95% confidence interval, 88-94). Higher relative dose intensity (≥70 vs. <70%) during the first 6 weeks and better Eastern Cooperative Oncology Group performance status (0 vs. ≥1) were associated with longer progression-free survival (24.0 vs. 20.1 weeks; P = 0.011; and 24.1 vs. 16.9 weeks; P < 0.001) and higher 24-week overall survival rate (94 vs. 83%; P < 0.001; and 96 vs. 83%; P < 0.001). Increased progression-free survival and overall survival rates were associated with specific adverse events. Cox proportional hazard modeling adjusted for relative dose intensity and performance status established hand-foot syndrome (hazard ratio = 0.636; 95% confidence interval, 0.456-0.888) and leukopenia (hazard ratio = 0.683; 95% confidence interval, 0.492-0.948) occurring within 12 weeks were significantly correlated with increased progression-free survival. CONCLUSION: Sunitinib showed good efficacy and tolerable safety. Factors associated with greater efficacy were relative dose intensity, performance status and specific early adverse events.

Early transplantation of mesenchymal stem cells after spinal cord injury relieves pain hypersensitivity through suppression of pain-related signaling cascades and reduced inflammatory cell recruitment.

Bone marrow-derived mesenchymal stem cells (BMSC) modulate inflammatory/immune responses and promote motor functional recovery after spinal cord injury (SCI). However, the effects of BMSC transplantation on central neuropathic pain and neuronal hyperexcitability after SCI remain elusive. This is of importance because BMSC-based therapies have been proposed for clinical treatment. We investigated the effects of BMSC transplantation on pain hypersensitivity in green fluorescent protein (GFP)-positive bone marrow-chimeric mice subjected to a contusion SCI, and the mechanisms of such effects. BMSC transplantation at day 3 post-SCI improved motor function and relieved SCI-induced hypersensitivities to mechanical and thermal stimulation. The pain improvements were mediated by suppression of protein kinase C-γ and phosphocyclic AMP response element binding protein expression in dorsal horn neurons. BMSC transplants significantly reduced levels of p-p38 mitogen-activated protein kinase and extracellular signal-regulated kinase (p-ERK1/2) in both hematogenous macrophages and resident microglia and significantly reduced the infiltration of CD11b and GFP double-positive hematogenous macrophages without decreasing the CD11b-positive and GFP-negative activated spinal-microglia population. BMSC transplants prevented hematogenous macrophages recruitment by restoration of the blood-spinal cord barrier (BSCB), which was associated with decreased levels of (a) inflammatory cytokines (tumor necrosis factor-α, interleukin-6); (b) mediators of early secondary vascular pathogenesis (matrix metallopeptidase 9); (c) macrophage recruiting factors (CCL2, CCL5, and CXCL10), but increased levels of a microglial stimulating factor (granulocyte-macrophage colony-stimulating factor). These findings support the use of BMSC transplants for SCI treatment. Furthermore, they suggest that BMSC reduce neuropathic pain through a variety of related mechanisms that include neuronal sparing and restoration of the disturbed BSCB, mediated through modulation of the activity of spinal-resident microglia and the activity and recruitment of hematogenous macrophages.

[Ossification of the posterior longitudinal ligament (OPLL) and the ligamentum flavum (OLF)].

The adult population is frequently sustained with ossification of the posterior longitudinal ligament (OPLL) and/or the ligamentum flavum (OLF) of the spine and the diseases may subsequently result is serious spinal cord insult with profound paralysis of the extremities. These pathologies are genetically denoted metaplasia of the elastic fibers of the ligament with consequent ectopic ossification process. The spinal cord is chronically compressed and will result in profound motor paralysis with sensory deficit. Both diseases are well imaged on CT and MRI, showing a various magnitude of spinal cord compression.

Perioperative patient safety indicators and hospital surgical volumes.

BACKGROUND: Since the late 1990s, patient safety has been an important policy issue in developed countries. To evaluate the effectiveness of the activities of patient safety, it is necessary to quantitatively assess the incidence of adverse events by types of failure mode using tangible data. The purpose of this study is to calculate patient safety indicators (PSIs) using the Japanese Diagnosis Procedure Combination/per-diem payment system (DPC/PDPS) reimbursement data and to elucidate the relationship between perioperative PSIs and hospital surgical volume. METHODS: DPC/PDPS data of the Medi-Target project managed by the All Japan Hospital Association were used. An observational study was conducted where PSIs were calculated using an algorithm proposed by the US Agency for Healthcare Research and Quality. We analyzed data of 1,383,872 patients from 188 hospitals who were discharged from January 2008 to December 2010. RESULTS: Among 20 provider level PSIs, four PSIs (three perioperative PSIs and decubitus ulcer) and mortality rates of postoperative patients were related to surgical volume. Low-volume hospitals (less than 33rd percentiles surgical volume per month) had higher mortality rates (5.7%, 95% confidence interval (CI), 3.9% to 7.4%) than mid- (2.9%, 95% CI, 2.6% to 3.3%) or high-volume hospitals (2.7%, 95% CI, 2.5% to 2.9%). Low-volume hospitals had more deaths among surgical inpatients with serious treatable complications (38.5%, 95% CI, 33.7% to 43.2%) than high-volume hospitals (21.4%, 95% CI, 19.0% to 23.9%). Also Low-volume hospitals had lower proportion of difficult surgeries (54.9%, 95% CI, 50.1% to 59.8%) compared with high-volume hospitals (63.4%, 95% CI, 62.3% to 64.6%). In low-volume hospitals, limited experience may have led to insufficient care for postoperative complications. CONCLUSIONS: We demonstrated that PSIs can be calculated using DPC/PDPS data and perioperative PSIs were related to hospital surgical volume. Further investigations focusing on identifying risk factors for poor PSIs and effective support to these hospitals are needed.

Prognostic value of changes in spinal cord signal intensity on magnetic resonance imaging in patients with cervical compressive myelopathy.

BACKGROUND CONTEXT: Signal intensity on preoperative cervical magnetic resonance imaging (MRI) of the spinal cord has been shown to be a potential predictor of outcome of surgery for cervical compressive myelopathy. However, the prognostic value of such signal remains controversial. One reason for the controversy is the lack of proper quantitative methods to assess MRI signal intensity. PURPOSE: To quantify signal intensity and to correlate intramedullary signal changes on MRI T1- and T2-weighted images (WIs) with clinical outcome and prognosis. STUDY DESIGN: Retrospective case study. PATIENT SAMPLE: Patients (n=148; cervical spondylotic myelopathy, n=102 and ossified posterior longitudinal ligament, n=46) who underwent surgery for cervical compressive myelopathy and had high signal intensity change on sagittal T2-WI MRI before surgery between 2006 and 2010. OUTCOME MEASURE: Neurologic assessment was conducted with the Japanese Orthopedic Association (JOA) scoring system for cervical myelopathy. The rate of neurologic improvement was calculated with the use of preoperative and postoperative JOA scores. METHODS: Quantitative analysis of MRI signal on both T1- and T2-WIs via use of the signal intensity ratio (SIR; signal intensity of lesion relative to that at C7-T1 disc level) was performed. Correlations between SIR on T1- and T2-WIs and preoperative JOA score, JOA improvement rate, disease duration, and MRI morphologic classification (cystic or diffuse type) were analyzed. Multivariate regression analysis for JOA improvement rate was also analyzed. In a substudy, 25 patients underwent follow-up MRI starting from 6 months after surgery to analyze the relationship between changes in SIR on follow-up MRI and clinical outcome. RESULTS: SIR on T1-WIs, but not SIR on T2-WIs, correlated with postoperative neurologic improvement. The disease duration correlated negatively with SIR on T1-WIs and JOA improvement rate but not with SIR on T2-WIs. SIR on T2-WIs of "cystic type" was significantly greater than of "diffuse type," but SIR on T1-WI and JOA improvement rate were not different in the two types. Stepwise multivariate regression analysis indicated that SIR on T1-WIs and long disease duration were significant predictors of postoperative neurologic outcome. SIR on follow-up T1-WI and changes in SIR on T1-WI after surgery correlated positively with postoperative improvement rate. SIR on follow-up T2-WI and changes on T2-WI correlated negatively with postoperative neurologic improvement. CONCLUSIONS: Our results suggest that low intensity signal on preoperative T1-WIs but not T2-WIs correlated with poor postoperative neurologic outcome. Furthermore, decreased signal intensity on postoperative T1-WIs and increased signal intensity on postoperative T2-WIs are predictors of poor neurologic outcome.

(18)F-FDG PET/CT for Diagnosis of Osteosclerotic and Osteolytic Vertebral Metastatic Lesions: Comparison with Bone Scintigraphy.

STUDY DESIGN: A retrospective study. PURPOSE: The aims of this study were to investigate the diagnostic value of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in PET/computed tomography (CT) in the evaluation of spinal metastatic lesions. OVERVIEW OF LITERATURE: Recent studies described limitations regarding how many lesions with abnormal (18)F-FDG PET findings in the bone show corresponding morphologic abnormalities. METHODS: The subjects for this retrospective study were 227 patients with primary malignant tumors, who were suspected of having spinal metastases. They underwent combined whole-body (18)F-FDG PET/CT scanning for evaluation of known neoplasms in the whole spine. (99m)Tc-methylene diphosphonate bone scan was performed within 2 weeks following PET/CT examinations. The final diagnosis of spinal metastasis was established by histopathological examination regarding bone biopsy or magnetic resonance imaging (MRI) findings, and follow-up MRI, CT and (18)F-FDG PET for extensively wide lesions with subsequent progression. RESULTS: From a total of 504 spinal lesions in 227 patients, 224 lesions showed discordant image findings. For 122 metastatic lesions with confirmed diagnosis, the sensitivity/specificity of bone scan and FDG PET were 84%/21% and 89%/76%, respectively. In 102 true-positive metastatic lesions, the bone scan depicted predominantly osteosclerotic changes in 36% and osteolytic changes in 19%. In 109 true-positive lesions of FDG PET, osteolytic changes were depicted predominantly in 38% while osteosclerotic changes were portrayed in 15%. CONCLUSIONS: (18)F-FDG PET in PET/CT could be used as a substitute for bone scan in the evaluation of spinal metastasis, especially for patients with spinal osteolytic lesions on CT.

The prevalence and phenotype of activated microglia/macrophages within the spinal cord of the hyperostotic mouse (twy/twy) changes in response to chronic progressive spinal cord compression: implications for human cervical compressive myelopathy.

BACKGROUND: Cervical compressive myelopathy, e.g. due to spondylosis or ossification of the posterior longitudinal ligament is a common cause of spinal cord dysfunction. Although human pathological studies have reported neuronal loss and demyelination in the chronically compressed spinal cord, little is known about the mechanisms involved. In particular, the neuroinflammatory processes that are thought to underlie the condition are poorly understood. The present study assessed the localized prevalence of activated M1 and M2 microglia/macrophages in twy/twy mice that develop spontaneous cervical spinal cord compression, as a model of human disease. METHODS: Inflammatory cells and cytokines were assessed in compressed lesions of the spinal cords in 12-, 18- and 24-weeks old twy/twy mice by immunohistochemical, immunoblot and flow cytometric analysis. Computed tomography and standard histology confirmed a progressive spinal cord compression through the spontaneously development of an impinging calcified mass. RESULTS: The prevalence of CD11b-positive cells, in the compressed spinal cord increased over time with a concurrent decrease in neurons. The CD11b-positive cell population was initially formed of arginase-1- and CD206-positive M2 microglia/macrophages, which later shifted towards iNOS- and CD16/32-positive M1 microglia/macrophages. There was a transient increase in levels of T helper 2 (Th2) cytokines at 18 weeks, whereas levels of Th1 cytokines as well as brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF) and macrophage antigen (Mac)-2 progressively increased. CONCLUSIONS: Spinal cord compression was associated with a temporal M2 microglia/macrophage response, which may act as a possible repair or neuroprotective mechanism. However, the persistence of the neural insult also associated with persistent expression of Th1 cytokines and increased prevalence of activated M1 microglia/macrophages, which may lead to neuronal loss and demyelination despite the presence of neurotrophic factors. This understanding of the aetiopathology of chronic spinal cord compression is of importance in the development of new treatment targets in human disease.

Fracture of the acetabulum: a retrospective review of ninety-one patients treated at a single institution.

Acetabular fracture result in fairly good outcome after the anatomic reduction in the displaced fracture fragments and damaged joint structure, but some patients will inevitably suffer from hip joint problems during their courses after the insult. We retrospectively reviewed 91 patients with acetabular fractures to investigate the causes of clinical failure and relationship among the fracture types, selected treatment options and their courses. Ninety-one patients (73 men and 18 women) with an average age of 49 years (range 18-80) at the time of injury were followed up for an average of 8.6 years (range 2-18). Judet-Letournel classification of fracture type and Matta's rating regimen of functional and radiographic patient' assessment were conducted. Conservative treatment was provided in 20 patients, in which 19 attained excellent/good, and one fair clinical results. All achieved excellent/good radiographic outcome. Surgically treated patients (n = 71) with critical dislodgement of the fracture fragment showed that 64 (90%) attained excellent/good and 7 (10%) fair/poor clinical outcomes. Sixty-three (89%) attained excellent/good and 8 (11%) fair/poor postoperative radiographic outcome. Five patients with poor radiographic outcome after surgery subsequently required total hip arthroplasty, due to the development of hip joint osteoarthritis in 3 and femoral head avascular necrosis in 2. We conclude that displacement of the joint surface should be reduced to less than 3 mm in accordance with the selection of the most appropriate surgical approach for open reduction/fixation in each fracture type; however, comminuted fracture and avascular necrosis of the femoral head may be the cause of poor clinical results.

Dislocated intra-articular femoral head fracture associated with fracture-dislocation of the hip and acetabulum: report of 12 cases and technical notes on surgical intervention.

This report describes case series of the femoral head fractures associated with fracture-dislocation of the hip joint to evaluate the mid- and long-term outcomes and to highlight the surgical technique of fixation of the femoral head from the posterior trochanteric flip osteotomy approach. Twelve patients (6 men and 6 women) with dislocated femoral head fractures (mean age at the time of injury, 56 years; range, 23-80) were followed up for mean period of 9.7 years (range, 5-20). All dislocations were reduced within less than 6 h after the injury. The type of femoral head fracture was classified according to the Pipkin classification on radiographs and CT. Five patients were classified as type I, 2 as type II, 2 as type III, and 3 as type IV. The clinical and radiological outcomes were assessed by Thompson and Epstein's regimen. Excluding 2 patients with Pipkin type III, the outcome of 9 patients was excellent/good, and poor in 1. The latter patient sustained Pipkin type IV and developed osteoarthritis 1 year after surgery and consequently required total hip arthroplasty. We conclude that small fragment of the femoral head less than 1 cm can be removed, while larger fragments should be fixed by bioabsorbable screws or pins in all types of femoral head fractures. In Pipkin type IV fractures, surgeons should always take anatomical reduction in the acetabulum into consideration during surgery.

Modified metaphyseal-loading anterolaterally flared anatomic femoral stem: five- to nine-year prospective follow-up evaluation and results of three-dimensional finite element analysis.

We have designed a proximal-fitting, anterolaterally flared, arc-deposit hydroxyapatite-coated anatomical femoral stem (FMS-anatomic stem; KYOCERA Medical, Osaka, Japan) for cementless total hip arthroplasty (THA) for Japanese patients with dysplastic hip osteoarthritis, using a nonlinear three-dimensional finite element analysis simulating loading conditions. The Anatomic Fit stem was modified in the region of the arc-sprayed surface, to allow more proximal appearance of spot welds. The aim of the present study was to analyze the clinical and radiographic outcomes of patients who underwent THA using this stem. We reviewed 73 consecutive patients (79 hips; 13 men 16 hips; 60 women 63 hips; age at surgery, 57.6 years, range, 35-78) who underwent cementless THA using the Anatomic Fit stem, at a follow-up period of 7.1 years (range, 5.1-9.4). Harris Hip score improved from 40.7 ± 17.1 before surgery to 91.0 ± 5.2 points at follow-up. The 7.1-year stem survival rate was 100%. Radiographs at follow-up confirmed the stability of the femoral stems within the femoral canal in all cases, with sufficient bone ingrowth. None of the patients had subsidence of the stem exceeding 2.0 mm within the femoral canal or changes in varus or valgus position of more than 2.0°. The Anatomic Fit stem provided excellent results. The nonlinear three-dimensional finite element analysis demonstrated that the stem-bone relative motion was 10 µm at the proximal end of the stem and proximal load transfer. Our analysis confirmed reduced radiolucency around the stem, minimal subsidence, appropriate stress shielding, and promising medium-term stability within the femoral canal.