JSIMD Journal

Introduction

Distal radius morphometry plays a crucial role in the clinical assessment and treatment of wrist fractures. Accounting for a significant proportion of all upper limb fractures, distal radius fractures present a common challenge in orthopaedic practice [1,2]. Additionally, understanding the normal values of distal radius morphometry is essential for achieving successful outcomes. Furthermore, positive ulnar variance has been identified as a potential risk factor for the development of Kienbock’s disease [3]. (Figure 1) showing normal value measurement of the distal radius and how its measured [4].

The intricate interplay between distal radius morphometry and wrist biomechanics has been the focus of previous investigations [5]. Among the key morphometric parameters, palmar tilt, radial inclination, radial height, and ulnar variance have emerged as critical determinants. In a pioneering cadaver study conducted by Short et al. in 1987, the significance of palmar tilt was demonstrated. Increased dorsal angulation was found to elevate the load transmitted through the ulna, leading to concentrated pressure distribution on the ulnar and radial articular surfaces.

Similarly, the effects of radial shortening and decreased radial inclination have been extensively documented [6]. The evaluation of distal radius morphology using anterior-posterior and lateral wrist radiographs have faced significant criticism from certain authors who question its reliability and limited reproducibility. One of the major challenges associated with this radiological assessment method is accurately determining the radial axis in the anterior-posterior view [4,7,8]. In recent years, several studies have highlighted the impact of even slight rotational variations in wrist positioning during radiography on these measurements. These variations have the potential to negatively influence treatment decisions. Recognizing racial disparities in distal radius morphometry is also important, as different populations have been found to exhibit distinct characteristics in this regard [8,9].

Unfortunately, in the context of clinical practice in Saudi Arabia, the reliance on Western figures for reduction is to investigate the morphometric parameters of the distal radius in the Saudi adult population. By conducting techniques is common due to the lack of comprehensive local database. This knowledge gap underscores the need to establish population-specific normative values to guide clinical decision-making accurately. Therefore, the aim of this study a systematic examination and measurement of these parameters, we seek to contribute valuable data that can enhance the precision and efficacy of distal radius fracture management in our local context. The findings of this study will provide orthopaedics surgeons in Saudi Arabia with a tailored reference for restoring anatomical alignment and optimizing treatment outcomes. By bridging this knowledge gap and shedding light on the morphometric characteristics of the distal radius in the Saudi population, we anticipate that our research will significantly impact clinical practice, leading to improved patient care and better-informed treatment decisions (Figure 1).

Figure 1: Normal value measurement of the distal radius and how its measured [4], Radial Hight X= 11mm, Radial inclination R= 22°, Volar tilt D=10°.

Methods

Study design and Setting

Retrospective single-facility-based descriptive cross study was carried out at King Abdulaziz Naval base, Armed Forces Hospital (KANB-AFH) in Jubail, Saudi Arabia.

Instrument

Consecutive wrist radiographs of patients who presented with wrist related complaints at the emergency unit, FCM and OPD during the study period were evaluated.for in seek of authenticity and to avoid the inter observer error , all the morphometric measurements were done by a single independent personnel. Sample size and sampling technique

We used the following equation in calculating the sample size

n= N/1+N(e)²

where N = population size = 505,162 which is the total population for the Jubail city e = Level of precision n= Sample size = 390

we used simple randomized sampling technique in sample selection.

Inclusion and exclusion criteria

We have included radiographs with standard radiographic protocol (true anterior-posterior and lateral) of the wrist in this study. Also, we included wrists with fused physeal plates only and excluded the others.

We excluded the entire wrist x-rays of the unossified bone and showing the irregularities due to structural deformity, injured distal end radius, and pathological conditions (i.e., arthritis) because they could have been responsible for the mismeasurement. Furthermore, Films that are rotated or not centered on the wrist have been excluded.

Ethical consideration and data collection

The study followed the principles of the Helsinki Declaration and was approved by the ethical committees of King Abdul Aziz Naval base, Armed Forces Hospital and the Directorate of Health Affairs, Jubail City, Saudi Arabia. The data were collected between January 2018 and January 2021.

Statistical Analysis

The Statistical Package for the Social Sciences (SPSS version 23.0) IBM Corp., Armonk, NY, USA was used to enter, edit and analyse the data. We calculated the percentage of each category of the social and demographics variables. We also calculated mean, standard deviation and range of for the volar tilt, radial height, and radial inclination variables Comparison of means has been carried out by using the independent t-test with significance set at p < 0.05.

Results

A total of 389 participants were included in the study, with complete data available for age, gender, volar tilt, radial height, and radial inclination. The mean age of the participants was 32.30 years (SD ± 11.48), ranging from 18 to 82 years old. In terms of gender distribution, 75.3% (n = 293) of the participants were male, while 24.7% (n = 96) were female. When comparing both genders, a statistically significant difference was found in radial height. The mean radial height was 12.68 mm (SD ± 2.00 mm) for males and 11.60 mm (SD ± 1.99 mm) for females.

Regarding volar tilt, the mean measurement was 13.28°, with a standard deviation of ±3.03°. The observed range of volar tilt values observed in the sample ranged from 2.900° to 29.930°. For radial height, the mean value was 12.41 mm, with a standard deviation of ± 2.05 mm. The range of radial height measurements spanned from 6.91 mm to 22.55 mm. As for radial inclination, the mean measurement was 22.93°, with a standard deviation of ±3.47°. The range of radial inclination values ranged from 10.15° to 33.21°.

When comparing the right side and the left side, a statistically significant difference was observed in radial height and radial inclination. For radial height, the mean measurement was 12.6842 mm (SD ± 2.00 mm) on the right side and 11.6093 mm (SD ± 1.99 mm) on the left side. Regarding radial inclination, the mean measurement was 22.9919° (SD ± 3.44°) on the right side and 22.7472° (SD ± 3.57°) on the left side.

The results of the independent t-tests indicated a statistically significant difference for radial height when comparing between genders (p < 0.05), and for both radial height and radial inclination when comparing between the right and left sides (p < 0.05). These findings demonstrate significant variations in radial height and radial inclination between genders and between the right and left sides. These differences have significant implications for understanding the anatomical characteristics and potential clinical implications in the studied population (Tables 1,2 & 3).

Table 1: Distribution of volar tilt, radial inclination and radial height, in n=389 subjects.

Table 2: Distribution of morphometric parameters (Mean ± standard deviation) in genders.

Table 3: Distribution of morphometric parameters for left and right side.

Discussion

Fractures of the distal radius that cause a loss of the normal downward angulation of the wrist result in increased stress on the joints between the ulna and carpal bones, as well as the joint between the radius and the scaphoid bone [10].This increased stress is primarily concentrated along the back part of the joint. It is established that these heightened loads contribute to pain and, over time, can lead to the early development of joint degeneration. Therefore, it is recommended to strive for a precise realignment of all distal radius fractures in order to restore the normal anatomy. In cases where a fracture has healed in a misaligned position with dorsal angulation, considering an osteotomy may be necessary to reduce the abnormal stresses on the joint between the distal radius and the ulna and carpal bones. Thus, the normal values of volar tilt, radial height, and radial inclination need to be known for orthopaedic surgeons who are practicing in a specific population, Saudi Arabia in our case [6].

Moreover, the findings emphasize the role of distal end radius morphometry in determining the clinical outcomes of wrist injuries. In our study, we did not measure the ulnar variance, as it is not significant in assessing the quality of reduction. It plays a role in other wrist pathologies like Kienbock disease but not in distal radial fracture [11,12].

As described in the results section, the mean volar tilt was 13.28° with a standard deviation (SD) of  ± 3.03°, while the mean radial height was 12.41 mm (SD ±2.05 mm), and the mean radial inclination was 22.93° (SD ± 3.47°). (Table 4)  will show the comparison between our findings and other previously published studies.

Table 4 : Comparison between this research and other previously published studies.