ABSTRACT
The radial artery is a vital access point for various cardiovascular and neurological interventions yet detailed morphometric studies in African populations are limited. This study aimed to investigate the radial artery dimensions in thirty adult body donors housed in the Department of Clinical Anatomy, University of KwaZulu‐Natal, Durban, South Africa. The external and internal diameters, along with wall thickness of the radial artery, were measured at three anatomical sites viz. the point of origin, at the wrist joint and in the anatomical snuffbox bilaterally using a digital vernier calliper in sixty upper limb specimens (BREC/00006978/2024). There was a progressive distal tapering pattern, with the external diameters of the radial artery decreasing from its point of origin to the anatomical snuffbox. The internal diameter of the radial artery was 2.98 ± 0.76 mm at the origin, 2.20 ± 0.75 mm at the wrist joint and 1.75 ± 0.69 mm in the anatomical snuffbox. The wall thickness of the radial artery also decreased distally, from its point of origin to the anatomical snuffbox. There were no statistically significant differences between biological sex or laterality. The internal radial artery diameters suggest that a 5 French (5Fr) sheath may be suitable in 32% of upper limbs at the wrist and in 38% of upper limbs in the anatomical snuffbox. The findings of this study can contribute to the existing knowledge in this field and may help clinicians during cardiovascular and neurological interventional procedures within this select sample.
Keywords: adult, donors, forearm radial artery, morphometry, snuffbox radial artery, white South African sample
1. Introduction
The radial artery develops embryologically from the axial artery (Schoenwolf et al. 2009; Singh 2020). At the apex of the cubital fossa, the radial artery arises as one of the terminal branches of the brachial artery which provides vasculature to the lateral side of the index finger, thumb, carpal bones, elbow joint and the postero‐lateral side of the forearm (Moore et al. 2018; Sgueglia et al. 2018; Narsinh et al. 2021; Brennan et al. 2025; Marchese et al. 2025). The radial artery travels between the flexor and extensor groups of muscles in the forearm, lying deep to the brachioradialis muscle in the proximal half of the forearm (Moore et al. 2018; Drake et al. 2020; Narsinh et al. 2021).
In the middle third of the forearm, the radial artery is laterally related to the radial nerve (superficial branch) (Drake et al. 2020). While distally, the radial artery, which is covered by fascia and skin, lies anterior to the pronator quadratus muscle and lateral to the tendon of the flexor carpi radialis (Drake et al. 2020). Proximal to the wrist, the radial artery branches into a superficial palmar branch before winding around the lateral aspect of the wrist, where it traverses the anatomical snuffbox—a region bounded by the tendons of the extensor pollicis longus muscle, abductor pollicis longus muscle and the extensor pollicis brevis muscle (Moore et al. 2018; Roh and Lee 2018; Drake et al. 2020; Marchese et al. 2025; Hallett Reid et al. 2023).
The radial artery courses through the anatomical snuffbox in close proximity to the scaphoid and trapezium carpal bones (Moore et al. 2018; Roh and Lee 2018; Daralammouri et al. 2022; Dawani et al. 2022; Hallett Reid et al. 2023; Brennan et al. 2025). This anatomical relationship establishes the snuffbox as a critical landmark for both anatomical education and clinical interventions, including cardiovascular and neurological procedures.
The diameter of the radial artery is a critical morphometric parameter with direct clinical implications, as it influences the success of trans‐radial interventions, vascular grafts and catheterization procedures (Alasmari 2021; Narsinh et al. 2021; Daralammouri et al. 2022; Bhatia et al. 2023). Therefore, knowledge of the diameter of the radial artery is crucial as it assists the clinician in selecting various sheath sizes during trans‐radial coronary interventions and enhances microsurgical techniques (Nasr 2012).
While numerous studies have documented the diameter of the radial artery in various populations, data from the African continent and Southern Africa in particular, remain scarce. Furthermore, data including the anatomical snuffbox, a site of growing clinical interest for distal radial access, are limited. Therefore, this study aimed to document the morphometric characteristics of the radial artery in terms of the external and internal diameters and wall thickness at the point of origin, wrist joint and in the anatomical snuffbox in a select sample of adult White South African body donors.
2. Materials and Methods
This study was a descriptive, cross‐sectional cadaveric morphometric investigation. A convenience sampling method was employed utilizing thirty adult embalmed body donors from the Department of Clinical Anatomy at the University of KwaZulu‐Natal, South Africa. Institutional ethical approval was obtained from the ethics committee (BREC/00006978/2024).
2.1. Inclusion and Exclusion Criteria
Adult body donors of both biological sexes, and all population groups obtained from the University of KwaZulu‐Natal were included in this study. Body donors with signs of surgical intervention and damage to the radial artery were excluded.
2.2. Study Procedure
The radial artery was dissected as per standardized protocol (Detton and Tank 2017). All morphometric parameters were measured in triplicate using a digital vernier calliper (EIS Digital Vernier 150 mm) by a single observer during the same session, with the calliper repositioned between attempts. Measurements were recorded and transferred to a password‐protected Excel spreadsheet. The morphometric parameters were analysed as follows:
2.2.1. Wrist Circumference
The bilateral wrist circumference was measured using a flexible tape measure. The tape was positioned around the wrist at the level of the distal radio‐ulnar joint, passing over Lister's tubercle on the dorsal aspect of the radial bone and the styloid process of the ulnar bone.
2.2.2. Diameter of the Radial Artery
The internal and external diameters of the radial artery were measured bilaterally at three measurement points, that is, at its point of origin from the brachial artery (Figure 1), at the wrist joint, and in the anatomical snuffbox (Figure 2) (Adapted from: Al Talalwah et al. 2015; Wessel et al. 2015; Getachew et al. 2018; Tariq et al. 2020; Varalakshmi 2021; Mahajan et al. 2022). The external diameter of the artery was measured first, after which the artery was incised at each specific measurement point. Then the internal (luminal) diameter of the artery was recorded.
FIGURE 1.
Measurement of radial artery at the point of origin (indicated by the red line). Blue dot: Brachial artery; Green dot: Ulnar artery; Pink dot: Radial artery.
FIGURE 2.
Measurement of radial artery at wrist joint (indicated by the red line) and in the anatomical snuffbox (indicated by the yellow line). Blue dot: Radial artery; Purple dot: Radial artery in the anatomical snuffbox; Pink dot: Extensor retinaculum; Green dot: Tendon of extensor pollicis longus muscle.
2.2.3. Wall Thickness of the Radial Artery
The bilateral wall thickness of the radial artery was calculated as half the difference between the average external and internal diameters (Formula 1) measured at three points, that is, at its point of origin from the brachial artery, at the wrist joint and in the anatomical snuffbox.
Formula 1: Wall thickness calculation.
2.2.4. Sheath Size Selection
Sheath compatibility was assessed based on the internal diameter of the radial artery at the wrist joint and anatomical snuffbox. Sheath sizing categories were guided by the radial artery diameter ranges corresponding to the French (Fr) sheath sizes, as described by Hobby et al. (2021). The measured internal diameter at each anatomical level was categorized into the appropriate Fr size group when it fell within the diameter range for that sheath size as defined by Hobby et al. (2021).
2.3. Statistical Analysis
The data was assessed for normality using the Kolmogorov–Smirnov and Shapiro–Wilk tests. Normally distributed data were presented as means and standard deviations (SD) and analysed using a t‐test, Levene's test for equality of variances and Pearson's correlation test. For non‐normally distributed data, numerical measurements were presented as medians and interquartile ranges and analysed using the Mann–Whitney U test. Reliability was assessed using the intraclass correlation coefficient based on a two‐way random‐effects model where both people effects and measures effects are random. A p‐value of ≤ 0.05 was considered statistically significant. All analyses were performed using IBM SPSS Statistics software (version 30). As this was an exploratory anatomical study aimed at describing the morphometric parameters rather than testing predefined hypotheses, no adjustments were made for multiple comparisons. Therefore, the p‐values should be interpreted in light of this context.
3. Results
A total of thirty adult body donors (n = 60 upper limbs) were used in this study. The reliability analysis revealed excellent consistency across the three attempts, with Cronbach's Alpha values ranging from 0.997 to 1.000. The inter‐item correlations were consistently high and the intraclass correlation coefficients (ICCs) for both single measures and average measures confirmed the strong agreement between the attempts (p < 0.001).
The age of the adult body donors ranged between 52 and 99 years, with an average age of 77 ± 11 years. The sample was predominantly female (53.3%), and all the body donors in this study were of the White South African population group. The morphometric parameters of the radial artery are summarized according to laterality (Table 1) and biological sex (Table 2).
TABLE 1.
Diameter and wall thickness of the radial artery according to laterality (mm).
| Body side | Radial artery | Mean (±SD) | p | |
|---|---|---|---|---|
| Male | Female | |||
| Right side (External) | Point of origin | 5.21 (2.23) a | 4.56 (0.98) a | 0.07 |
| Wrist joint | 4.01 (0.72) a | 3.79 (0.48) a | 0.38 | |
| Snuffbox | 3.05 (0.82) | 3.25 (0.89) | 0.53 | |
| Left side (External) | Point of origin | 4.73 (0.99) | 5.40 (1.51) | 0.16 |
| Wrist joint | 3.89 (0.63) a | 3.81 (0.69) a | 0.59 | |
| Snuffbox | 3.11 (0.88) | 3.47 (1.06) | 0.32 | |
| Right side (Internal) | Point of origin | 2.79 (0.68) | 3.28 (0.89) | 0.10 |
| Wrist joint | 2.07 (0.77) | 2.35 (0.71) | 0.32 | |
| Snuffbox | 1.71 (0.64) | 1.81 (0.74) | 0.68 | |
| Left side (Internal) | Point of origin | 2.90 (0.71) | 3.00 (0.75) | 0.71 |
| Wrist joint | 2.08 (0.84) | 2.33 (0.67) | 0.37 | |
| Snuffbox | 1.72 (0.82) | 1.74 (0.60) | 0.94 | |
| Right side (Wall thickness) | Point of origin | 1.22 (0.61) | 0.97 (0.60) | 0.28 |
| Wrist joint | 0.75 (0.32) | 0.84 (0.45) | 0.55 | |
| Snuffbox | 0.63 (0.43) a | 0.59 (0.51) a | 0.69 | |
| Left side (Wall thickness) | Point of origin | 1.20 (0.59) | 0.92 (0.42) | 0.14 |
| Wrist joint | 0.82 (0.44) | 0.89 (0.32) | 0.63 | |
| Snuffbox | 0.86 (0.50) | 0.69 (0.35) | 0.29 | |
Median (IQR).
TABLE 2.
Diameter and wall thickness of the radial artery according to biological sex (mm).
| Radial artery | Mean (±SD) | p | |||
|---|---|---|---|---|---|
| Right side | Left side | Total | |||
| External | Point of origin | 4.95 (1.05) a | 5.12 (1.70) a | 5.02 (1.51) a | 0.97 |
| Wrist joint | 3.90 (0.76) a | 3.88 (0.68) a | 3.88 (0.71) a | 0.99 | |
| Snuffbox | 3.14 (0.85) | 3.28 (0.97) | 3.21 (0.91) | 0.56 | |
| Internal | Point of origin | 3.02 (0.81) | 2.95 (0.72) | 2.98 (0.76) | 0.73 |
| Wrist joint | 2.20 (0.75) | 2.20 (0.76) | 2.20 (0.75) | 0.98 | |
| Snuffbox | 1.76 (0.68) | 1.73 (0.72) | 1.75 (0.69) | 0.90 | |
| Wall thickness | Point of origin | 1.00 (0.60) a | 0.92 (0.69) a | 0.95 (0.67) a | 0.97 |
| Wrist joint | 0.80 (0.39) | 0.86 (0.38) | 0.83 (0.38) | 0.52 | |
| Snuffbox | 0.62 (0.47) a | 0.74 (0.57) a | 0.67 (0.55) a | 0.34 | |
Median (IQR).
3.1. Correlation
Correlation analyses were conducted to investigate possible predictive relationships between the proximal and distal arterial dimensions, which could have clinical significance for planning distal radial access. There was a strong correlation between the external diameter of the left radial artery in the anatomical snuffbox and the internal diameter of the left radial artery at the wrist joint (r = 0.73, p < 0.001). There was a strong correlation between the internal diameter of the left radial artery at the wrist joint and the internal diameter of the left radial artery at the point of origin (r = 0.87, p < 0.001), as well as the internal diameter of the right radial artery at the wrist joint (r = 0.75, p < 0.001).
There was a strong correlation between the internal diameter of the right radial artery in the anatomical snuffbox and the internal diameter of the right radial artery at the wrist joint (r = 0.86, p < 0.001). There was a strong correlation between the internal diameter of the left radial artery in the anatomical snuffbox and the internal diameter of the left radial artery at the wrist joint (r = 0.82, p < 0.001) and at the point of origin (r = 0.78, p < 0.001), as well as the internal diameter of the right radial artery in the anatomical snuffbox (r = 0.72, p < 0.001).
There was a moderate correlation between the left wrist circumference and the internal diameter of the right radial artery at the point of origin (r = 0.42, p = 0.021). There was a moderate correlation between the left wrist circumference and the internal diameter of the right radial artery at the wrist joint (r = 0.38, p = 0.041).
3.2. Sheath Size
The internal diameter of the radial artery was less than 1.8 mm in 33% of the sample at the wrist joint and in 50% of the sample in the anatomical snuffbox. The internal diameter of the radial artery ranged from 1.8 mm to 2.6 mm (which corresponds to a 5Fr regular sheath) in 32% of the sample at the wrist joint and in 38% of the sample in the anatomical snuffbox. Meanwhile, the internal diameter of the radial artery was between 2.6 mm and 3.1 mm (6Fr regular sheath) in 20% of the sample at the wrist joint and 8% in the anatomical snuffbox. The internal diameter of the radial artery was greater than 3.1 mm in 15% of the sample at the wrist joint and in 3% of the sample in the anatomical snuffbox.
4. Discussion
The morphometric characteristics of the radial artery possess substantial clinical significance for cardiovascular interventions and neuro‐interventions. Alasmari (2021) indicated that understanding the diameter of the radial artery is essential for enhancing the success rate during transradial coronary interventions. Al Talalwah et al. (2015) observed that clinicians must be cognizant of the diameter, wall thickness and variability of the radial artery, as numerous surgical and invasive procedures are performed in the cubital region, which can help minimize iatrogenic complications. Nasr (2012) asserted that the diameter of the radial artery markedly influences the success of angiographic, graft replacement, catheterization and bypass operations. Therefore, awareness of the diameter of the radial artery is crucial as it assists cardiologists and radiologists in selecting various sheath sizes during transradial coronary interventions and enhances microsurgical techniques. This present study aimed to document the morphometric characteristics in terms of the diameter of the radial artery at the point of origin, at the wrist joint and in the anatomical snuffbox.
4.1. External Diameter of the Radial Artery
The external diameter of the radial artery reported in the present study was larger than the findings reported in cadaveric studies in the Saudi Arabian (Nasr 2012); British (Al Talalwah et al. 2015); Ethiopian (Getachew et al. 2018); Pakistani (Tariq et al. 2020); and Indian (Mahajan et al. 2022) populations (Table 3). At the wrist joint, the external diameter also exceeded the findings reported in cadaveric studies by Nasr (2012); Al Talalwah et al. (2015); Yilmaz et al. (2015); Getachew et al. (2018); Tariq et al. (2020); Alasmari (2021); Varalakshmi (2021); Mahajan et al. (2022); and Ellis et al. (2025), although Wessel et al. (2015) reported comparatively larger values (Table S1). Similarly, the external diameter in the anatomical snuffbox observed in the present study was greater than that reported by Haładaj et al. (2018); Mahajan et al. (2022); and Wang et al. (2024) (Table 4).
TABLE 3.
External diameter of the radial artery at the point of origin.
| Author (year) | Modality | Population | Sample size | Diameter (mm) of the radial artery | |||
|---|---|---|---|---|---|---|---|
| Body side (R: Right, L: Left) | Average | Biological sex | |||||
| Male | Female | ||||||
| Nasr (2012) | Cadaveric | Saudi Arabian | 100 |
R: 3.07 (±0.49) L: 3.02 (±0.48) |
— |
R: 3.3 (±0.7) L: 3.3 (±0.7) |
R: 3.07 (±0.5) L: 3.02 (±0.48) |
| Al Talalwah et al. (2015) | Cadaveric | British | 68 |
R: 3.52 (±0.85) L: 3.45 (±0.79) |
3.48 |
R: 3.71 (±0.91) L: 3.63 (±0.84) |
R: 3.25 (±0.69) L: 3.20 (±0.66) |
| Getachew et al. (2018) | Cadaveric | Ethiopian | 78 |
R: 4.40 (±1.26) L: 4.44 (±1.51) |
— |
R: 4.45 (±1.35) L: 4.41 (±1.5) |
R: 4.36 (±1.18) L: 4.49 (±1.51) |
| Tariq et al. (2020) | Cadaveric | Pakistani | 84 |
R: 3.53 (±0.86) L: 3.46 (±0.78) |
— |
R: 3.26 (±0.68) L: 3.64 (±0.85) |
R: 3.26 (±0.68) L: 3.21 (±0.67) |
| Mahajan et al. (2022) | Cadaveric | Indian | 30 |
R: 4 (±0.75) L: 3.8 (±0.76) |
3.9 | — | — |
| Present study | Cadaveric | South African | 60 |
R: 4.95 (±1.05) L: 5.12 (±1.70) |
5.02 (±1.51) |
R: 5.21 (±2.23) L: 4.73 (±0.99) |
R: 4.56 (±0.98) L: 5.40 (±1.51) |
TABLE 4.
External diameter of the radial artery in the anatomical snuffbox.
With regards to laterality, the present study reported a greater external diameter on the left side compared to the right side. This finding aligns with Getachew et al. (2018) but contrasts with other cadaveric studies that reported larger right‐sided dimensions or no laterality differences. The variability in laterality findings across the literature suggests that the radial artery asymmetry may not be consistent across populations and could be influenced by anatomical variation, functional dominance or demographic characteristics.
Notably, the present study demonstrated a progressive decrease in the external diameter from the point of origin to the anatomical snuffbox, which is consistent with the proximal‐to‐distal tapering pattern described by Getachew et al. (2018). This tapering is clinically relevant in the context of the distal radial artery access, where smaller vessel calibre may influence procedural planning.
Differences in the external diameter between the present study and previous studies may be attributed to the methodological variation, including differences in anatomical landmarks, measurement instruments and whether the vessels were assessed under physiological or cadaveric conditions. Cadaveric vessels are measured in a non‐pressurized state, which differs from in vivo imaging studies where arterial tone and intra‐luminal pressure are preserved. In addition, demographic factors, anthropometric variability and the advanced mean age of the present donor cohort may influence the arterial dimensions. These considerations highlight the relevance of contextual analysis when comparing morphometric data across different study paradigms and populations. The biological sex‐based differences in the external diameter of the right radial artery at the point of origin and the external diameter of the radial artery at the wrist joint (bilaterally) between the present study and previous studies can be attributed to the non‐normal distribution of these variables in this cohort, which contrasted with the normally disturbed data, underlying the means and standard deviation, reported by previous studies.
4.2. Internal Diameter of the Radial Artery
The internal diameter of the radial artery in the present study demonstrated variability when compared to previous studies. At the point of origin, the findings reported in the present study were smaller than those reported by various authors in cadaveric studies as shown in Table S2 but larger than the findings reported by Shima et al. (1996); and Mudiraj and Dhobale (2015). At the wrist joint, the present study's findings were smaller than those reported by various authors in cadaveric studies as summarized in Table S3 but larger than those reported by Prakash and Saniya (2014). In the anatomical snuffbox, Swetha et al. (2023); and Mudiraj and Dhobale (2015) reported a larger internal diameter compared to the findings of the present study.
Biological sex differences were observed, with males demonstrating larger internal diameters than females across anatomical levels. This is consistent with previous findings and probably represents established biological sex differences in body size and arterial calibre. However, the magnitude of these differences varies across populations, suggesting that demographic and anthropometric factors may influence arterial dimensions. The progressive reduction in internal diameter from the point of origin to the anatomical snuffbox aligns with the concept of physiological arterial tapering. From a procedural perspective, the distal reduction in luminal calibre may be relevant for distal radial artery access as smaller vessel diameters may increase technical complexity.
The differences between the present findings and previous studies can be attributed to methodology, study design and demographical factors of the study population. The advanced mean age of the present donor cohort may have influenced the internal diameters due to age‐related vascular remodelling.
4.3. Wall Thickness of the Radial Artery
The wall thickness of the radial artery at the point of origin in the present study differed from the findings reported by various authors in cadaveric studies as shown in Table 5. A greater wall thickness was observed on the right side, consistent with the findings reported by Getachew et al. (2018). Males exhibited greater bilateral wall thickness at the point of origin than females, in contrast to the findings reported by Al Talalwah et al. (2015), who reported greater bilateral wall thickness in females.
TABLE 5.
Wall thickness of the radial artery at the point of origin.
| Author (year) | Modality | Population | Sample size | Wall thickness of the radial artery (mm) | ||
|---|---|---|---|---|---|---|
| Body side (R: Right; L: Left) | Biological sex | |||||
| Male | Female | |||||
| Al Talalwah et al. (2015) | Cadaveric | British | 68 |
R: 0.11 (±0.05) L: 0.12 (±0.00) |
R: 0.06 (±0.11) L: 0.09 (±0.02) |
R: 0.19 (±0.01) L: 0.15 (±0.06) |
| Getachew et al. (2018) | Cadaveric | Ethiopian | 78 |
R: 0.37 (±0.22) L: 0.34 (±0.23) |
R: 0.37 (±0.22) L: 0.29 (±0.91) |
R: 0.36 (±0.21) L: 0.37 (±0.27) |
| Tariq et al. (2020) | Cadaveric | Pakistani | 84 |
R: 0.12 (±0.06) L: 0.13 (±0.00) |
R: 0.18 (±0.02) L: 0.08 (±0.03) |
R: 0.18 (±0.02) L: 0.16 (±0.07) |
| Present study | Cadaveric | South African | 60 |
R: 1.00 (±0.60) L: 0.92 (±0.69) |
R: 1.22 (±0.61) L: 1.20 (±0.59) |
R: 0.97 (±0.60) L: 0.92 (±0.42) |
At the wrist joint, the present study's findings were larger than those reported by Al Talalwah et al. (2015) in a British population, Getachew et al. (2018) in an Ethiopian population and Tariq et al. (2020) in a Pakistani population (Table 6). The radial artery wall thickness was greater on the left side in the present study, which concurs with findings reported by various cadaveric studies (Table 6).
TABLE 6.
Wall thickness of the radial artery at the wrist joint.
| Author (year) | Modality | Population | Sample size | Wall thickness of the radial artery (mm) | ||
|---|---|---|---|---|---|---|
| Body side (R: Right; L: Left) | Biological sex | |||||
| Male | Female | |||||
| Al Talalwah et al. (2015) | Cadaveric | British | 68 |
R: 0.15 (±0.10) L: 0.16 (±0.13) |
R: 0.17 (±0.13) L: 0.18 (±0.16) |
R: 0.12 (±0.05) L: 0.12 (±0.09) |
| Getachew et al. (2018) | Cadaveric | Ethiopian | 78 |
R: 0.25 (±0.22) L: 0.28 (±0.24) |
R: 0.26 (±0.21) L: 0.22 (±0.19) |
R: 0.25 (±0.23) L: 0.35 (±0.28) |
| Tariq et al. (2020) | Cadaveric | Pakistani | 84 |
R: 0.16 (±0.11) L: 0.17 (±0.14) |
R: 0.13 (±0.06) L: 0.19 (±0.17) |
R: 0.13 (±0.06) L: 0.13 (±0.08) |
| Present study | Cadaveric | South African | 60 |
R: 0.80 (±0.39) L: 0.86 (±0.38) |
R: 0.75 (±0.32) L: 0.82 (±0.44) |
R: 0.84 (±0.45) L: 0.89 (±0.32) |
The wall thickness values reported in the present study were greater than those reported in previous cadaveric studies. However, wall thickness in this study was calculated using the formula: 0.5 × (average external diameter—average internal diameter), which may include adventitial tissue and connective tissue components. Additionally, the embalming process may result in vascular wall stiffening, luminal collapse or tissue dehydration, which can potentially contribute to an increased measured wall thickness. Differences in methodology and embalming processes used in cadaveric dissections may therefore limit the direct comparability of wall thickness measurements. Additionally, the advanced mean age of the body donors may have contributed to age‐related vascular remodelling.
4.4. Sheath Size
The present study noted that the internal diameter of the radial artery was between 1.8 and 2.6 mm (corresponding to a 5Fr sheath) in 32% of the sample at the wrist joint and in 38% of the sample in the anatomical snuffbox. Yilmaz et al. (2015) reported that a 5Fr sheath was safer for trans‐radial catheterization based on their findings. However, the sheath size suitability estimates presented in this study are derived from static and embalmed cadaveric measurements. While these findings provide useful anatomical baseline data, they must be interpreted cautiously when extrapolating to clinical practice. In vivo, arterial dimensions may be influenced by vasomotor tone, arterial elasticity, blood pressure and procedural factors such as vasospasm. Therefore, sheath selection in clinical settings should be individualized and guided by patient‐specific assessment. Future studies incorporating ultrasound or angiographic measurements in living patients would provide valuable insight into sheath suitability under physiological conditions.
4.5. Limitations
The sample size in this study was relatively small and consisted of body donors from a single center, which may limit the generalizability of the findings. Additionally, the body donors used in this study all belonged to the same ethnic group (White South African). Therefore, ethnicity‐based differences in the external and internal diameters as well as the wall thickness of the radial artery could not be documented. The body donors were predominantly elderly, with an advanced mean age. Therefore, age‐related vascular changes may have influenced the morphometric measurements obtained in this study. Furthermore, detailed clinical histories of the body donors were not available; therefore, the potential impact of comorbidities on the radial artery morphometry could not be assessed.
The embalming process can cause varying levels of tissue shrinkage or swelling, and the absence of physiological intravascular pressure may lead to the collapse of vessel lumens. As a result, absolute measurements of both the external and internal diameters may differ from those observed in in vivo conditions.
The arterial wall thickness was calculated indirectly from the external and internal diameter measurements rather than measured directly. The absence of direct wall thickness measurement or histological validation may cause discrepancies when comparing these findings with previous literature. The inter‐observer agreement was not assessed in this study.
5. Conclusion
This study investigated the morphometric parameters of the radial artery in a select White adult body donor cohort at the University of KwaZulu‐Natal. Measurements of the external and internal diameters, along with the wall thickness, were taken at three anatomical sites: at the point of origin, at the wrist joint and in the anatomical snuffbox bilaterally. The findings demonstrated a progressive distal tapering pattern, with the radial artery decreasing in size from the point of origin to the anatomical snuffbox. Notably, no significant differences were observed between biological sex or laterality. The internal diameter measurements suggest that a 5 French sheath may be suitable for trans‐radial interventions in approximately one‐third of the sample at the wrist joint and slightly more in the anatomical snuffbox. The findings of the present study can contribute to the existing knowledge in this field and may assist clinicians during cardiovascular and neurological interventions within this select adult donor cohort.
Author Contributions
Aleisha J. Singh: All persons listed as authors have contributed substantially to the conceptualization, writing – original draft, writing – review and editing. Rohen Harrichandparsad: All persons listed as authors have contributed substantially to the conceptualization, writing – original draft, writing – review and editing. Lelika Lazarus: All persons listed as authors have contributed substantially to the conceptualization, writing – original draft, writing – review and editing.
Funding
Financial assistance was received from the National Research Foundation (NRF). Opinions and conclusions expressed are those of the author and do not necessarily represent those of the NRF.
Ethics Statement
Institutional ethical approval was obtained from the ethics committee (BREC/00006978/2024). The authors hereby confirm that every effort was made to comply with all local and international ethical guidelines and laws concerning the use of human cadaveric donors in anatomical research.
Consent
For the dissemination of this research, written informed consent was secured from the University of KwaZulu‐Natal's Body Donor Programme.
Conflicts of Interest
The authors declare no conflicts of interest.
Supporting information
Table S1: External diameter of the radial artery at the wrist joint.
Table S2: Internal diameter of the radial artery at the point of origin.
Table S3: Internal diameter of the radial artery at the wrist joint.
Acknowledgements
The authors sincerely thank those who donated their bodies to science so that anatomical research could be performed. Results from such research can potentially increase mankind's overall knowledge that can then improve patient care. Therefore, these donors and their families deserve our highest gratitude.
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Table S1: External diameter of the radial artery at the wrist joint.
Table S2: Internal diameter of the radial artery at the point of origin.
Table S3: Internal diameter of the radial artery at the wrist joint.
Data Availability Statement
The data that support the findings of this study are available from the corresponding author upon reasonable request.