Morphometric analyses of clavicle's nutrient foramen

Morphometric and topographic evaluations of principal nutrient foramina of the ilium

BACKGROUND

Nutrient arteries pass through the nutrient foramina and reach the spongious part or medullary cavity of the bones. The arterial blood supply and nutrient foramina of the ilium have not been well described in the literature. The aim of this study is to define the numbers and localizations of nutrient foramina of the ilium on the internal surface in accordance with the pelvic brim, as well as the external surface, and furthermore the distances between these foramina with certain anatomical landmarks.

METHODS

This study was performed on 57 dry hip bones. The foramina on the external and internal surfaces of the ilium were evaluated separately. The external surface of the ilium was divided into 4 regions in accordance with the gluteal lines to determine the localizations of the nutrient foramina. The foramina on the internal surface were evaluated according to whether they were above or below the pelvic brim. The diameters of the foramina and their nearest distances to certain anatomical landmarks were measured. Furthermore, the risk area of the region above the pelvic brim was determined.

RESULTS

: The foramina that were found on the external surface of the ilium were distributed mainly between anterior and inferior gluteal lines (42 foramina-37.17%) and below the inferior gluteal line (57 foramina-50.44%). On the internal surface, 54 nutrient foramina were found above the pelvic brim and 81 were found below.

DISCUSSION

The localizations and configurations of all nutrient foramina on the ilium were evaluated morphometrically for the first time.

The human clavicle's nutrient foramen's prevalence, number, location, and direction: A systematic review and meta-analysis

INTRODUCTION

The clavicle's nutrient foramen is a surrogate marker for its nutrient artery. Knowing its location may be useful for interpreting fractures and to avoid iatrogenic lesions. The aim of this review was to determine the prevalence, number, location, and direction of the nutrient foramen.

METHODS

Embase, Medline, PubMed, Scopus, and Web of Science were searched and supplemented by Google Scholar, hand-searching major anatomical journals, and the reference list of included studies (updated March 08, 2022). Titles and abstracts were screened for eligibility, and observational studies with quantitative data were included based on full text evaluation. Internal validity was assessed using the anatomical quality assessment tool. Pooled prevalence proportions were derived using a random effects DerSimonian-Laird model using the Freeman-Tukey double arcsine transformation with Miller's inverse back-transformation.

RESULTS

From 18,889 unique reports, 33 studies with 3760 clavicles and 3358 foramina were included. All studies suffered from untransparent reporting. The prevalence of the nutrient foramen was 97.75%, 95% confidence interval 94.70%-99.60%. It was mainly found as a single foramen on the middle third segment's posterior surface with acromial (lateral) obliquity. Results were stable over time, robust to sensitivity analyses, albeit limited by unexplained heterogeneity and asymmetry.

CONCLUSION

This review may aid in interpreting fractures passing through a high-risk area (mean foraminal index range 36.31-61.03%) for lesions to the nutrient artery. Practical implications are a need to update current inaccurate textbook descriptions and further advocate evidence-based anatomy to improve conduct and reporting of anatomical research.

3D Mapping of Bone Channel of Blood Supply to Femoral Head in Proximal Femur

Background

A detailed depiction of nutrient foramina is useful for defining guidelines and minimising iatrogenic damage during hip surgery. Therefore, this study aimed to define the location and frequency of nutrient foramina in the proximal femur using mapping techniques.

Methods

One hundred dry human cadaveric proximal femurs, comprising 56 left and 44 right femurs, were scanned using a three-dimensional scanner, with scanning distance 200 mm, precision 0.01 mm, and measuring point 0.04 mm. The image resolution of 1,310,000 pixels was obtained. Digital imaging models were acquired from the proximal femur surface. All the nutrient foramina in each model were identified and marked. The nutrient foramina models were superimposed on one another and oriented to fit a standard template of the femur’s proximal aspect. Three-dimensional mapping in the proximal femur’s nutrient foramina was performed.

Results

The nutrient foramina’s location and dense zones were identified. The dense zones were distributed along the vascular course and gaps between the muscle attachment sites. Eighteen dense zones were identified and found to be location-dependent. They were located in the central part of the fovea capitis femoris, subcapital and basicervical areas of the femoral neck, and muscle attachment gaps of the femoral trochanter.

Conclusions

The terminal branch of the nutrient vessels entering the nutrient foramina is at risk for iatrogenic damage during hip surgeries, especially in cases of close bone exposures. There are 18 dense zones that need to be considered for a safer approach to the proximal femur. To minimise iatrogenic damage to the nutrient vessels entering the nutrient foramina, the dense areas should be avoided when technically possible.