Relationship between the degree of subchondral collapse and articular surface irregularities in osteonecrosis of the femoral head.

Articular surface irregularities are often observed in collapsed femoral heads with osteonecrosis, while the effects of the degree of collapse on the articular surface are poorly understood. We first macroscopically assessed the articular surface irregularities on 2-mm coronal slices obtained using high-resolution microcomputed tomography of 76 surgically resected femoral heads with osteonecrosis. These irregularities were observed in 68/76 femoral heads, mainly at the lateral boundary of the necrotic region. The mean degree of collapse was significantly larger for femoral heads with articular surface irregularities than for those without (p < 0.0001). Receiver operating characteristic analysis showed that the cutoff value for the degree of collapse in femoral heads with articular surface irregularities at the lateral boundary was 1.1 mm. Next, for femoral heads with <3-mm collapse (n = 28), articular surface irregularities were quantitatively assessed based on the number of automatically counted negative curvature points. Quantitative evaluation showed that the degree of collapse was positively correlated with the presence of articular surface irregularities (r = 0.95, p < 0.0001). Histological examination of articular cartilage above the necrotic region (n = 8) revealed cell necrosis in the calcified layer and abnormal cellular arrangement in the deep and middle layers. In conclusion, articular surface irregularities of the necrotic femoral head depended on the degree of collapse, and articular cartilage was already altered even in the absence of macroscopically determined gross irregularities.

Posterior Pelvic Tilt in the Standing Position Might Be Associated with Collapse Progression in Post-Collapse Stage Osteonecrosis of the Femoral Head.

OBJECTIVE: Excessive pelvic tilt has been reported to impair the biomechanical loading of the hip joint. However, the influence of pelvic tilt in osteonecrosis of the femoral head (ONFH) remains unclear. This study aims to assess whether sagittal pelvic posture in the standing position correlates with progression of femoral head collapse in post-collapse stage ONFH. METHODS: This is a single-center retrospective study. We investigated 107 patients (107 hips; 73 males and 34 females; mean age, 48 years) diagnosed with Association of Research Circulation Osseous (ARCO) stage III ONFH at the first visit and who subsequently underwent surgical treatment in our institution from July 2016 to December 2020. The sagittal pelvic posture in the standing position before surgery was quantified as the angle formed by the anterior pelvic plane and the vertical z-axis in the sagittal view (APP angle). An APP angle <0° indicated posterior pelvic tilt. Progression of femoral head collapse was calculated as collapse speed. The following factors potentially associated with collapse speed were evaluated by exploratory data analysis followed with multiple linear regression analysis: sex, age, BMI, etiology, pelvic incidence, contralateral hip condition, time interval between the first visit and surgery, size of necrotic lesion, location of necrotic lesion, and APP angle. RESULTS: As ONFH progressed from ARCO stage IIIA to stage IV, APP angle decreased significantly and continuously (stage IIIA, -0.2° ± 5.5°; stage IIIB, -3.7° ± 5.8°; stage IV, -7.1° ± 6.4°). The factors significantly associated with collapse speed were size of necrotic lesion (p = 0.0079), location of necrotic lesion (p = 0.0190), and APP angle (p < 0.0001). APP angle showed a negative correlation with collapse speed (r = -0.40, p < 0.0001). After stratifying by size of necrotic lesion (<50% and ≥50% involvement) and location of necrotic lesion (JIC type C1 and C2), a significant negative correlation was observed between APP angle and collapse speed in each group (JIC type C1 with <50% involvement, r = -0.69, p < 0.0001; JIC type C1 with ≥50% involvement, r = -0.58, p = 0.0475; JIC type C2 with <50% involvement, r = -0.51, p = 0.0124; JIC type C2 with ≥50% involvement, r = -0.39, p = 0.0286). CONCLUSIONS: Our results suggest that posterior pelvic tilt in the standing position occurred as ONFH progressed from ARCO stage IIIA to stage IV, which might be associated with progression of femoral head collapse in ONFH.

Endoscopic Detachable Snare Ligation Therapy for Colonic Diverticular Hemorrhage Improves Procedure Time Compared to Endoscopic Band Ligation.

BACKGROUND: The clipping method is widely used in endoscopic hemostasis for colonic diverticular hemorrhage. Recently, rebleeding was shown to be less common in ligation therapy than in clipping. Ligation methods include endoscopic band ligation (EBL) and endoscopic detachable snare ligation (EDSL). No studies have compared procedure times for EBL and EDSL. The present study aimed to compare EDSL and EBL in terms of procedure time. METHODS: In this single-center retrospective observational cohort study, we evaluated the data of 39 patients who underwent EBL or EDSL for colonic diverticular hemorrhage. The primary and secondary outcomes measured were the total procedure time and early rebleeding rate, respectively. RESULTS: Among the 39 patients included in the study, 18 underwent EBL, and 21 underwent EDSL for hemostasis. The median total pro- cedure times for the EBL and EDSL groups were 50 (range, 30-80) minutes and 35 (range, 18-55) minutes, respectively, demonstrating that the total colonoscopy time was significantly shorter in the EDSL group (P < .001). The early rebleeding rate was 11.1% (2/18) in the EBL group and 4.8% (1/21) in the EDSL group (P = .246). CONCLUSION: Important improvements in procedure time were achieved in the EDSL group. Based on our results, we believe that EDSL may reduce patient and endoscopist burden.

The Discrepancy in the Posterior Boundary of Necrotic Lesion Between Axial and Oblique Axial Slices of MRI in Patients with Osteonecrosis of the Femoral Head.

BACKGROUND: Little is known concerning differences in assessment of anteroposterior osteonecrotic lesion of the femoral head (ONFH) between the axial plane parallel to the body axis (axial) and the axial plane parallel to the femoral neck axis (oblique axial) using magnetic resonance imaging (MRI). This study aimed to compare the posterior boundary of necrotic lesions between the axial and oblique axial planes on MRI. METHODS: This study retrospectively reviewed 120 consecutive hips in 71 patients (47 males and 24 females; mean age, 42 years) with ONFH, for which both axial and oblique axial MRI slices were available. The posterior boundaries of the necrotic lesions were calculated as the ratio of posterior intact circumference to anteroposterior circumference of the femoral head using mid-axial and mid-oblique axial MRI slices. The necrotic angles, calculated using the modified Kerboul method, were compared between cases with progression and nonprogression of collapse. RESULTS: The mean posterior intact ratio in the axial slice was 49.2% (range, 8.6 to 85.1%), while that in the oblique axial slice was 33.5% (7.5 to 79.2%). The posterior intact ratio in the oblique axial slice significantly decreased compared to that in the axial slice (p < 0.0001). In cases with progression of collapse, the mean necrotic angle was significantly larger in the oblique axial slice than in the axial slice (p < 0.0001). The sensitivity and specificity of the necrotic angle with regard to the prognosis of the femoral head were both higher when using the oblique axial slice (sensitivity: 88.4%, specificity: 82.3%) than when using the axial slice (sensitivity: 85.1%, specificity: 62.0%). The posterior intact ratio at a mean of 6.8 mm superior to the mid-axial slice corresponded to that of the mid-oblique axial slice. CONCLUSION: Our findings suggest that the posterior boundaries of necrotic lesions differ between axial and oblique axial slices, and examination of the oblique axial MRI slice might be more suitable for predicting the prognosis of the femoral head. LEVEL OF EVIDENCE: Diagnostic-Investigating a diagnostic test. Level IV (Case series).

[A case of upper gastrointestinal bleeding due to a ruptured gastric aneurysm caused by arteriosclerosis derived from primary aldosteronism-induced hypertension].

A 77-year-old woman with a history of hypertension underwent upper gastrointestinal endoscopy for hematemesis, and vasodilation with erosion was detected. Contrast-enhanced computed tomography and abdominal angiography revealed a gastric aneurysm penetrating the stomach wall. Endoscopic hemostasis was thought to be not applicable to a ruptured aneurysm. Transcatheter arterial embolization was not performed because of technical difficulties. Therefore, local gastric resection was performed. It was later determined that the cause of the persistent hypertension was primary aldosteronism, which was thought to cause arteriosclerotic obstruction of the celiac, common hepatic, and splenic arteries, resulting in the formation of the gastric arterial aneurysm. In the case of upper gastrointestinal bleeding, keeping primary aldosteronism in mind as a differential diagnosis is important to make a precise diagnosis and suitable treatment selection.

Efficacy of Over-The-Scope Clip Method as a Novel Hemostatic Therapy for Colonic Diverticular Bleeding.

Colonic diverticular could bleed recurrently, and, sometimes, fatal massive bleeding could occur. However, the choice of endoscopic hemostasis remains controversial. Although the over-the-scope clip (OTSC) method has been reported to be effective, it has not been fully evaluated due to the small number of cases. This study aimed to evaluate the efficacy of the OTSC method for colonic diverticular bleeding. Between August 2017 and December 2020, 36 consecutive patients, including those who could not be treated using endoscopic band ligation (EBL) and those in whom re-bleeding had occurred after EBL, underwent the OTSC method for hemostasis of colonic diverticular bleeding at Hyogo Prefectural Awaji Medical Center. The procedure success rate, adverse events rate, early phase re-bleeding rate (within 30 days following primary hemostasis), and the requirement rate for additional transcatheter arterial embolization (TAE) or surgery were the outcomes assessed. The outcomes were procedure success rate 100%, adverse events rate 0%, early phase re-bleeding rate 8.3%, and additional TAE or surgery rate 0%. These results suggest that the OTSC method is a safe and effective treatment for managing colonic diverticular bleeding.

Risk factors for radiological changes after bipolar hemiarthroplasty for osteonecrosis of the femoral head.

OBJECTIVES: This study aimed to report the mid-term radiological outcomes of patients with bipolar hemiarthroplasty (BHA) for stage 3 osteonecrosis of the femoral head (ONFH), and to identify the risk factors for postoperative radiological changes. METHODS: We retrospectively investigated 62 patients (38 men and 24 women; mean age, 50.1 years) aged <70 years who underwent primary BHA for Association Research Circulation Osseous stage 3 ONFH between 1998 and 2010. The mean follow-up period after BHA was 12.8 years. The following changes were assessed on follow-up radiographs: outer head migration, polyethylene wear, and femoral osteolysis. The association between demographic data and the development of postoperative radiological changes was evaluated. RESULTS: Radiological changes were found in 20 hips (32.3%) at a mean of 8.1 years after BHA; of these, three hips (4.8%) underwent total hip arthroplasty conversion at a mean of 10.9 years after BHA. Both univariate and multivariate analysis revealed that younger age and female sex were independent risk factors for the development of postoperative radiological changes. CONCLUSION: The current results suggest that the indication of BHA should be carefully determined in young or female patients with ONFH, even when the disease is in the early stage.

Clinical benefit of the multibending endoscope for gastric endoscopic submucosal dissection: a randomized controlled trial.

BACKGROUND: Endoscopic submucosal dissection (ESD) is a technically difficult and time-consuming procedure. We aimed to investigate the efficacy and safety of ESD using a multibending endoscope to treat superficial gastrointestinal neoplasms. METHODS: Patients with a single early gastric cancer who met the absolute or expanded indications for ESD according to the Japanese gastric cancer treatment guidelines were enrolled and randomly assigned to undergo ESD using a conventional endoscope (C-ESD) or a multibending endoscope (M-ESD). Randomization was stratified by ESD operator experience and tumor location. The primary outcome was ESD procedure time, calculated as the time from the start of submucosal injection to complete removal of the tumor. RESULTS: 60 patients were analyzed (30 C-ESD, 30 M-ESD). The mean (standard deviation [SD]) ESD procedure times for M-ESD and C-ESD were 34.6 (SD 17.2) and 47.2 (SD 26.7) minutes, respectively (P = 0.03). Muscle layer damage occurred significantly less frequently with M-ESD (0.2 [SD 0.7] vs. 0.7 [SD 1.0]; P = 0.04). There were no significant differences between the two techniques in procedure time or damage to muscle layers for tumors located in the lower third of the stomach. CONCLUSIONS: ESD procedure time was significantly shorter with the multibending endoscope and fewer muscles were damaged. We recommend multibending endoscopy for ESD in the upper and middle thirds of the stomach to reduce procedure time and incidence of complications.

Proximal femoral morphology after transtrochanteric posterior rotational osteotomy for osteonecrosis of the femoral head: A three-dimensional simulation study.

BACKGROUND: Transtrochanteric posterior rotational osteotomy (PRO) is one of the joint-preserving surgeries for osteonecrosis of the femoral head. In general, postoperative femoral neck-shaft varus realignment is planned to obtain a sufficient intact articular surface of the femoral head in the weight-bearing portion. Unlike anterior rotational osteotomy, PRO allows for more than 90° rotation of the femoral head, resulting in more complicated morphology. However, little is known about the potential risk of postoperative femoral retroversion after PRO. This simulation study aims: 1) to assess whether postoperative femoral neck-shaft varus realignment can coexist with preserved femoral anteversion after PRO, 2) and whether postoperative proximal femoral morphology could be predicted with approximation equations. HYPOTHESIS: High degree (>90°) PRO is favourable for femoral neck-shaft varus realignment, but unfavourable for maintaining postoperative femoral anteversion. MATERIALS AND METHODS: PRO was simulated by using CT data from 10 hips in 10 healthy volunteers. During simulation, the intertrochanteric osteotomy plane was determined three-dimensionally based on anteroposterior-view line (the osteotomy line on anteroposterior view) and lateral-view line (the osteotomy line on lateral view). By changing either the angle of anteroposterior-view line or lateral-view line, we simulated 90°, 110°, 130° and 150° PRO. To clarify the effects of various posterior rotation angles on postoperative proximal femoral morphology, we made simplified PRO models through changing only the posterior rotation angle. RESULTS: In the 90°, 110°, 130° and 150° PRO models, the vertically inclined angle of anteroposterior-view line showed a significant positive correlation with femoral neck-shaft varus realignment (90° PRO, r=0.90; 110° PRO, r=0.95; 130° PRO, r=0.97; 150° PRO, r=0.99), while a significant negative correlation with postoperative femoral anteversion angle (90° PRO, r=-0.97; 110° PRO, r=-0.95; 130° PRO, r=-0.92; 150° PRO, r=-0.7). Likewise, the posteriorly tilted angle of lateral-view line showed a significant negative correlation with both femoral neck-shaft varus realignment (90° PRO, r=-0.81; 110° PRO, r=-0.81; 130° PRO, r=-0.79; 150° PRO, r=-0.72) and postoperative femoral anteversion angle (90° PRO, r=-0.90; 110° PRO, r=-0.89; 130° PRO, r=-0.92; 150° PRO, r=-0.88). In the simplified PRO models, the posterior rotation angle showed a significant positive correlation with femoral neck-shaft varus realignment (r=0.33), while a significant negative correlation with postoperative femoral anteversion angle (r=-0.76). The approximation equations for predicting the proximal femoral morphology after PRO were validated. DISCUSSIONS: It was confirmed that high-degree PRO (>90°) is favourable for femoral neck-shaft varus realignment, but works against preserving femoral anteversion. With the approximation equations developed in the current study, surgeons could examine the feasibility of PRO based on postoperative femoral anteversion. In terms of hip joint function and subsequent total hip arthroplasty, excessive deformities including femoral retroversion and severe varus deformity could be avoided. LEVEL OF EVIDENCE: IV; case series without control group.

Differences in the microarchitectural features of the lateral collapsed lesion between osteonecrosis and subchondral insufficiency fracture of the femoral head.

BACKGROUND: Like osteonecrosis of the femoral head (ONFH), subchondral insufficiency fracture of the femoral head (SIF) causes femoral head collapse. However, little is known about the differences between the two diseases regarding the morphological features of the collapsed lesion. We tested the hypothesis that the morphological features of the lateral collapsed lesion would differ between ONFH and SIF. METHODS: Twenty femoral heads histopathologically diagnosed as ONFH (n = 10) or SIF (n = 10) were used in this study. In the lateral collapsed lesion of each femoral head, cubic regions of interest (ROIs) were selected within the collapsed subchondral area and the nearby non-collapsed subchondral area. Micro-CT-based microarchitectural parameters were compared between the ROIs in each disease. Additionally, correlations between histopathological and microarchitectural features were evaluated. RESULTS: In ONFH, bone volume fraction, trabecular thickness, and bone mineral density in the collapsed area were all significantly lower than those in the nearby non-collapsed area where thickened bone trabeculae accompanied by appositional bone formation were invariably seen. On the other hand, in SIF there were no significant differences between the ROIs in any of these microarchitectural parameters. Histopathologically, varying degrees of callus formation overlying the fracture of the subchondral plate were seen around the lateral collapsed lesion. CONCLUSION: The morphological features of the lateral collapsed lesion were inconsistent between ONFH and SIF, suggesting different pathomechanisms of femoral head collapse.

Is bone mineral density lower in the necrotic lesion in pre-collapse osteonecrosis of the femoral head?

The purpose of this study was to clarify whether bone mineral density (BMD) of the necrotic lesion in precollapse osteonecrosis of the femoral head (ONFH) is reduced according to Hounsfield unit (HU) values on computed tomography (CT). The superior one-third of the femoral head in the coronal section was set as the region of interest (ROI) for the measurement of HU values. First, HU values of 101 control participants were assessed to identify relevant confounding factors. Next, the relationship between HU values and BMD on dual-energy X-ray absorptiometry (DXA) was verified. Then the mean HU value of the ROI in patients with pre-collapse ONFH was compared with that in propensity score-matched control participants. Finally, the HU values of the lateral boundary in the patients with and without subsequent collapse were compared. Multivariable analysis showed that both age and BMI were significantly correlated with the HU value, which showed a strong correlation with the BMD of the femoral neck on DXA (r = 0.92). In 25 ONFH patients and 25 propensity-matched control participants, no significant difference was found in the HU value of the ROI (p = .54). The mean HU value of the lateral boundary in patients with subsequent collapse was found to be significantly higher than that in patients without subsequent collapse (p < .01). The assessment of HU values on CT was useful for the evaluation of BMD of the femoral head. The current assessment did not demonstrate reduced bone mineral density of the necrotic lesion in pre-collapse ONFH.

Quantitative evaluation of bone-resorptive lesion volume in osteonecrosis of the femoral head using micro-computed tomography.

Objectives To quantify the volume of bone-resorptive lesions in post-collapse osteonecrosis of the femoral head (ONFH) using micro-computed tomography (micro-CT) and assess their characteristics in post-collapse ONFH. Methods We investigated 35 femoral heads resected from 35 patients with ONFH (20 men and 15 women; mean age, 47.2 years). On each of seven coronal high-resolution micro-CT slices of the femoral head, the bone-resorptive areas were extracted using bone microstructure measurement software. Next, the total bone-resorptive volume ratio, defined as the ratio of all bone-resorptive cross-sectional areas to all femoral head cross-sectional areas in all seven slices, was calculated. Associations between total bone-resorptive volume ratio and sex, age, ONFH-associated factors, patient workload levels, ONFH stage, ONFH type, necrotic volume on magnetic resonance imaging, and duration from the onset of pain to surgery were analyzed. Lesion location and the association between bone-resorptive lesion and collapse were also evaluated. Results The mean total bone-resorptive volume ratio was 7.0±6.0%, which varied significantly by ONFH stage (ARCO collapse quantitation 3A, 3.5±2.1%; 3B, 6.8±3.0%; and 3C, 13.6±8.8%). ONFH stage was independently associated with total bone-resorptive volume ratio (P<0.05). Furthermore, high bone-resorptive volume ratios were found in the anterior femoral head and were associated with collapse. Conclusions This study demonstrated that bone-resorptive volume in post-collapse ONFH was significantly associated with the disease stage, which was more widespread in the anterior portion of the femoral head than in the posterior portion.

Long-term hip survival and factors influencing patient-reported outcomes after transtrochanteric anterior rotational osteotomy for osteonecrosis of the femoral head: A minimum 10-year follow-up case series.

Objectives: This retrospective study aimed to assess long-term hip survival after transtrochanteric anterior rotational osteotomy (ARO) for osteonecrosis of the femoral head (ONFH) and identify factors influencing patient-reported outcome measures (PROMs) in patients with preserved joints.Methods: Altogether, 95 consecutive hips in 85 ONFH patients who underwent ARO during 2000-2007 (86.7% follow-up) were studied. Controls were 35 patients with 41 hips with ONFH managed conservatively for >1 year after collapse. We analyzed hip survival using the Kaplan-Meier method, with the endpoint defined as any therapeutic surgery related to ONFH. We also evaluated PROMs for both groups in patients with surviving hips and available radiographs at the final follow-up.Results: The 10-year hip survival rate after ARO was 85.4%, which was significantly higher than the 5-year rate in the control group (50.4%). Multiple regression analyses showed that the presence of osteoarthritic change after ARO was significantly associated with poor scores for both the Oxford Hip Score and the Short Form-12 Health Survey Physical Component Summary.Conclusions: ARO could effectively preserve hip joints with post-collapse ONFH, although the presence of osteoarthritic change could lead to lower satisfaction even among patients with long-term hip survival after ARO.