Combination of texture analysis and bone mineral density improves the prediction of fracture load in human femurs

Twenty-one excised femurs were studied using (1) a high-resolution digital X-ray device to estimate three textural parameters, (2) dual-energy X-ray absorptiometry (DXA) to measure bone mineral density (BMD), and (3) mechanical tests to failure. Textural parameters significantly correlated with BMD (p < 0.05) and bone strength (p < 0.05). Combining texture parameters and BMD significantly improved the fracture load prediction from adjusted r(2) = 0.74 to adjusted r(2) =0.82 (p < 0.05).

INTRODUCTION

The purpose of this study is to determine if the combination of bone texture parameters using a new high-resolution X-ray device and BMD measurement by DXA provided a better prediction of femoral failure load than BMD evaluation alone.

METHODS

The proximal ends of 21 excised femurs were studied using (1) a high-resolution digital X-ray device (BMA, D3A Medical Systems) to estimate three textural parameters: fractal parameter Hmean, co-occurrence, and run-length matrices, (2) DXA to measure BMD, and (3) mechanical tests to failure in a side-impact configuration. Regions of interest in the femoral neck, intertrochanteric region, and greater trochanter were selected for DXA and bone texture analysis. Every specimen was scanned twice with repositioning before mechanical testing to assess reproducibility using intraclass correlation coefficient (ICC) with 95% confidence interval. The prediction of femoral failure load was evaluated using multiple regression analysis.

RESULTS

Thirteen femoral neck and 8 intertrochanteric fractures were observed with a mean failure load of 2,612 N (SD, 1,382 N). Fractal parameter Hmean, co-occurrence, and run-length matrices each significantly correlated with site-matched BMD (p < 0.05) and bone strength (p < 0.05). The ICC of the textural parameters varied between 0.65 and 0.90. Combining bone texture parameters and BMD significantly improved the fracture load prediction from adjusted r(2) =0.74 to adjusted r(2) = 0.82 (p < 0.05).

CONCLUSION

In these excised femurs, the combination of bone texture parameters with BMD demonstrated a better performance in the failure load prediction than that of BMD alone.

The contribution of MRI to the diagnosis of traumatic tears of the anterior cruciate ligament

When faced with a clinical suspicion of knee ligament injury, MRI nowadays has a central role in the diagnostic strategy. In particular, it is essential for assessing the cruciate ligaments and any associated meniscal tears. The objective of this review is to present the various direct and indirect MRI signs of tearing of the anterior cruciate ligament (ACL) and then describe the lesions associated with it. The anatomical and clinical aspects are also discussed so that the contribution of MRI to the diagnosis and therapeutic management of an ACL tear can be better understood.

Treatment of degenerative meniscal tear with intrameniscal injection of platelets rich plasma

PURPOSE

The purpose of this retrospective study was to describe our preliminary results of intra-meniscal administration of platelet rich plasma (PRP) in patients with degenerative meniscal tears of the knee.

MATERIAL AND METHOD

Ten patients with degenerative meniscal tears according to the Stoller classification and without knee osteoarthritis were included. There were 7 men and 3 women with a mean age of 40.4±13.6 [SD] years (range: 18-59 years). Patients were prospectively assessed at baseline and 3- and 6-months after intra meniscal PRP administration. Evaluation included the knee injury and osteoarthritis outcome score (KOOS), pain visual analog scale, and return to competition and training. MRI follow-up was performed 6 months after PRP administration. Adverse events were recorded.

RESULTS

Volume of injected PRP was standardized to 4.0mL. Adverse events during PRP administration was moderate pain in 8 patients (8/10; 80%). Mean KOOS total score significantly improved from 56.6±15.7 (SD) to 72.7±18.5 (SD) (P=0.0007). All six patients practicing sports regularly were able to recover competition or training. In seven patients who underwent MRI follow-up at 6 months, MRI showed stability of the meniscal tears and similar Stoller grades.

CONCLUSION

Intra-meniscal administration of PRP under ultrasound guidance directly into meniscal degenerative lesions is feasible and safe. Further randomized controlled studies are needed to definitely confirm the effectiveness of this procedure.

Assessment of proximal femur microarchitecture using ultra-high field MRI at 7 Tesla

PURPOSE

The purpose of this study was to investigate bone microarchitecture of cadaveric proximal femurs using ultra-high field (UHF) 7-Tesla magnetic resonance imaging (MRI) and to compare the corresponding metrics with failure load assessed during mechanical compression test and areal bone mineral density (ABMD) measured using dual-energy X-ray absorptiometry.

MATERIALS AND METHODS

ABMD of ten proximal femurs from five cadavers (5 women; mean age=86.2±3.8 (SD) years; range: 82.5-90 years) were investigated using dual-energy X-ray absorptiometry and the bone volume fraction, trabecular thickness, trabecular spacing, fractal dimension, Euler characteristics, connectivity density and degree of anisotropy of each femur was quantified using UHF MRI. The whole set of specimens underwent mechanical compression tests to failure. The inter-rater reliability of microarchitecture characterization was assessed with the intraclass correlation coefficient (ICC). Associations were searched using correlation tests and multiple regression analysis.

RESULTS

The inter-rater reliability for bone microarchitecture parameters measurement was good with ICC ranging from 0.80 and 0.91. ABMD and the whole set of microarchitecture metrics but connectivity density significantly correlated with failure load. Microarchitecture metrics correlated to each other but did not correlate with ABMD. Multiple regression analysis disclosed that the combination of microarchitecture metrics and ABMD improved the association with failure load.

CONCLUSION

Femur bone microarchitecture metrics quantified using UHF MRI significantly correlated with biomechanical parameters. The multimodal assessment of ABMD and trabecular bone microarchitecture using UHF MRI provides more information about fracture risk of femoral bone and might be of interest for future investigations of patients with undetected osteoporosis.

[Lymphatic drainage of skin areas of head and neck: in vivo approach by the location of the sentinel node]

INTRODUCTION

The objective of the study was to determine the preferential territories of drainage of skin areas of the face and neck. This knowledge can guide the strategies of diagnostic (search for primary tumor skin to cervical lymphadenopathy) and treatment (determination of the extent of neck dissection to achieve in case of skin tumor).

MATERIALS AND METHODS

This is a retrospective study of the surgical procedures of sentinel node research between January 2003 and April 2011. The lymphoscintigraphic and intraoperative localization of the initial tumor site and sentinel lymph node were collected.

RESULTS AND DISCUSSION

One hundred and thirty-seven patients were included in the study. The parotid gland is a privileged territory of drainage of the head and neck skin. At cervical level, the submental region drains the lower and median part of the face (lips and chin). The posterior segments (IIb and V sector) were represented for the posterior locations of the head (ear, vertex), and cervical region.

Automated vertebral compression fracture detection and quantification on opportunistic CT scans: a performance evaluation

AIM

Since the majority of vertebral compression fractures (VCFs) are asymptomatic, they often go undetected on opportunistic CT scans. To reduce rates of undiagnosed osteoporosis, we developed a deep learning (DL)-based algorithm using 2D/3D U-Nets convolutional neural networks to opportunistically screen for VCF on CT scans. This study aimed to evaluate the performance of the algorithm using external real-world data.

MATERIALS AND METHODS

CT scans acquired for various indications other than a suspicion of VCF from January 2019 to August 2020 were retrospectively and consecutively collected. The algorithm was designed to label each vertebra, detect VCF, measure vertebral height loss (VHL) and calculate mean Hounsfield Units (mean HU) for vertebral bone attenuation. For the ground truth, two board-certified radiologists defined if VCF was present and performed the measurements. The algorithm analyzed the scans and the results were compared to the experts' assessments.

RESULTS

A total of 100 patients (mean age: 76.6 years ± 10.1[SD], 72% women) were evaluated. The overall labeling agreement was 94.9% (95%CI: 93.7%-95.9%). Regarding VHL, the 95% limits of agreement (LoA) between the algorithm and the radiologists was [-9.3, 8.6]; 94.1% of the differences lay within the radiologists' LoA and the intraclass correlation coefficient was 0.854 (95%CI: 0.822-0.881). For the mean HU, Pearson's correlation was 0.89 (95%CI: 0.84-0.92; p-value <0.0001). Finally, the algorithm's VCF screening sensitivity and specificity were 92.3% (95%CI: 81.5%-97.9%) and 91.7% (95%CI: 80.0%-97.7%), respectively.

CONCLUSIONS

This automated tool for screening and quantification of opportunistic VCF demonstrated high reliability and performance that may facilitate radiologists' task and improve opportunistic osteoporosis assessments.