Tribology of Replacement Hip Joints

Automated detection of the region of interest (ROI) is a critical step in the two-step classification system in several medical image applications. However, key information such as model parameter selection, image annotation rules, and ROI confidence score are essential but usually not reported. In this study, we proposed a practical framework of ROI detection by analyzing hip joints seen on 7399 anteroposterior pelvic radiographs (PXR) from three diverse sources. We presented a deep learning-based ROI detection framework utilizing a single-shot multi-box detector with a customized head structure based on the characteristics of the obtained datasets. Our method achieved average intersection over union (IoU) = 0.8115, average confidence = 0.9812, and average precision with threshold IoU = 0.5 (AP50) = 0.9901 in the independent testing set, suggesting that the detected hip regions appropriately covered the main features of the hip joints. The proposed approach featured flexible loose-fitting labeling, customized model design, and heterogeneous data testing. We demonstrated the feasibility of training a robust hip region detector for PXRs. This practical framework has a promising potential for a wide range of medical image applications.

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Evaluation of whole-body modalities for diagnosis of multifocal osteonecrosis—a pilot study

Arthritis Research & Therapy ◽

10.1186/s13075-021-02473-3 ◽

2021 ◽

Vol 23 (1) ◽

Author(s):

Shunichi Yokota ◽

Keita Sakamoto ◽

Yukie Shimizu ◽

Tsuyoshi Asano ◽

Daisuke Takahashi ◽

...

Keyword(s):

Study Data ◽

Whole Body ◽

Hematologic Disease ◽

Hip Joints ◽

Patient Demographics ◽

Examination Time ◽

History Of ◽

Body Magnetic Resonance Imaging ◽

The Cost ◽

Body Bone

Abstract Background This study aimed to investigate the ability of whole-body bone scintigraphy (WB-BS) in the detection of multifocal osteonecrosis (ON) compared to whole-body magnetic resonance imaging (WB-MRI) and to clarify the characteristics of patients with multifocal ON among those with ON of the femoral head (ONFH) using WB-MRI. Methods Forty-six patients who had symptomatic ONFH and underwent surgery in our hospital from April 2019 to October 2020 were included in the study. Data on patient demographics, including age, sex, body mass index (BMI), history of corticosteroid intake, alcohol abuse, smoking, and symptomatic joints, were collected from their medical records. All patients underwent WB-MRI and WB-BS before surgery. Results The agreement in the detection of ON by WB-MRI vs the uptake lesions by WB-BS in the hip joints was moderate (κ = 0.584), while that in other joints was low (κ < 0.40). Among the 152 joints with ON detected by WB-MRI, 92 joints (60.5%) were symptomatic, and 60 joints (39.5%) were asymptomatic. Twelve out of the 46 (26.0%) patients had multifocal (three or more distinct anatomical sites) ON. Nonetheless, while WB-BS detected symptomatic ON detected by WB-MRI as uptake lesions in 82.6% (76/92) of the joints, asymptomatic ON detected by WB-MRI was detected as uptake lesions in 21.7% (13/60) of the joints. All patients with multifocal ON had a history of steroid therapy, which was significantly higher than that in patients with oligofocal ON (P = 0.035). The patients with a hematologic disease had multifocal ON at a higher rate (P = 0.015). Conclusions It might be difficult for WB-BS to detect the asymptomatic ON detected by WB-MRI compared to symptomatic ON. Considering the cost, examination time, and radiation exposure, WB-MRI might be useful for evaluating multifocal ON. Larger longitudinal studies evaluating the benefits of WB-MRI for detecting the risk factors for multifocal ON are required.

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Ankylosis of Both Hip-Joints

Proceedings of the Royal Society of Medicine ◽

10.1177/003591570900201464 ◽

1909 ◽

Vol 2 (Study_Dis_Child) ◽

pp. 170-170

Author(s):

O. L. Addison

Keyword(s):

Hip Joints

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Correction of congenital deformity of hind limbs of cat by femoro-tarsal arthrodesis: a case report

Veterinární Medicína ◽

10.17221/1929-vetmed ◽

2008 ◽

Vol 53 (No. 8) ◽

pp. 452-455 ◽

Cited By ~ 1

Author(s):

J. Park ◽

K.R. Cho ◽

B.C. Sutradhar ◽

D. Chang ◽

S.H. Choi ◽

...

Keyword(s):

Computed Tomography ◽

Case Report ◽

Congenital Deformity ◽

Hip Joints ◽

Hind Limbs ◽

Satisfactory Outcome

Congenitally deformed tibia-fibulas of both hind limbs were diagnosed in a four-month-old, female, domestic shorthair cat that was unable to bear weight and whose movement was painful on both stifle and hock joints. Bleeding was observed repeatedly from the wound made by deformed tibias at the cranial sides of hock joints where the bones were exposed. Radiography and computed tomography revealed a corn-shaped tibia and bow shaped fibula which extended cranio-distally without formation of the hock joints. Femoro-tarsal arthrodesis was successfully executed on both hind legs after exclusion of the deformed and pliable tibia-fibulas. Follow-up radiography showed that bone fusions had gradually improved and were without complications. Postoperatively, the cat was capable of walking on the corrected hind legs and running on the movement of hip joints. To the authors’ knowledge, this is the 1st reported case of femoro-tarsal arthrodesis in a cat. In this case, femoro-tarsal arthrodesis resulted in a satisfactory outcome for congenitally deformed tibia-fibulas in cat.

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