Anatomic variation of the clavicle: A novel three‐dimensional study

Abstract

An understanding of the complex anatomy of the clavicle is helpful in the treatment of clavicular fractures. Using three-dimensional (3D) statistical shape analysis, the author presents a novel method to assess geometric morphology of the clavicle. Fifteen fresh frozen shoulder specimens were scanned using high-resolution computerized tomography (CT) but four were excluded from the study. A further 16 high-resolution CT scans of the clavicle were obtained by searching the hospital database. All 27 scans were reconstructed and subsequently imported into and analyzed using a specifically developed statistical software package. Using statistical shape analysis, geometric parameters were then measured. Both gender as well as side specific geometric morphology were observed. Clavicles in men were longer, wider, and thicker than in women. Right clavicles had a greater medial depth than left clavicles, especially in women. Clavicles in men had a greater lateral depth than in women. The sternal angle in women was larger than in men. Using 3D statistical shape analysis and applying it to the clavicle standardizes the study of its anatomy, rules out any variability, and calculates morphological parameters that are accurate, precise, and reproducible. This unique approach provides information that is useful not only to the clinician but also in the modification of current or design of future clavicle fixation devices. More importantly, from an anatomy standpoint, implementation of this novel approach in anatomical studies would eliminate intra- and interobserver variation and allow all studies to be standardized and thus more comparable.

Three‐dimensional corrective osteotomies of mal‐united clavicles—is the contralateral anatomy a reliable template for reconstruction?

“…This fact is also represented in the reconstruction template evaluation, by a significantly greater translation error along the X-axis (i.e., in medial-lateral direction) compared to the other axes. Consistent with our results, a significant greater length of the left clavicle was reported in the literature (Daruwalla et al, 2010;Cunningham et al, 2013;Bernat et al, 2014). A common hypothesis is the influence of hand dominance on the clavicle length because, considering that the majority of people are right handed, excessive motion of the dominant side results in increased wear of the clavicle ends over time (Daruwalla et al, 2010).…”

“…Consistent with our results, a significant greater length of the left clavicle was reported in the literature (Daruwalla et al, 2010;Cunningham et al, 2013;Bernat et al, 2014). A common hypothesis is the influence of hand dominance on the clavicle length because, considering that the majority of people are right handed, excessive motion of the dominant side results in increased wear of the clavicle ends over time (Daruwalla et al, 2010). Unfortunately, we were unable to correlate our findings with the handedness of our subjects as this data was unavailable.…”

“…Conventional preoperative planning using twodimensional (2D) radiographs does not always provide sufficient information to fully understand a complex three-dimensional (3D) deformity (Bachoura et al, 2013) (Simpson and Jupiter, 1996). Accordingly, 3D preoperative planning has become popular because it permits exact quantification and correction of a deformity in all six degrees of freedom (Daruwalla et al, 2010;Guitton and Ring, 2010;Oka et al, 2010). In these approaches, bilateral symmetry of the bones is assumed, permitting the use of the unaffected contralateral bone as 3D reconstruction template for the pathological side (Schweizer et al, 2010;Miyake et al, 2011;Schweizer et al, 2013Schweizer et al, , 2014.…”

An application of principal component analysis to the clavicle and clavicle fixation devices

“…Experience to date has shown that linear scaling is a dominant mode of variation in human anatomy [1]. This paper builds on geometric data and methodology presented in a previous study analyzing linear measurements [2] in order to provide detailed information relating to the modes of variation in three-dimensional (3D) shape that occur in the clavicle. It must be noted that while intramedullary and plate fixation are accepted and widely used methods of treatment for fractures of the clavicle, current clavicular implants overlook the variations in geometry of the bone.…”

Perceptions among occupational and physical therapy students of a nontraditional methodology for teaching laboratory gross anatomy

“…Other researchers have assessed the relative advantages of dissections versus prosections in medical school anatomy courses, typically concluding that cadaver dissections are a preferable way to teach future clinicians about the clinical relevance of anatomical facts and relationships (Hisley et al, 2008). Yet other studies have documented the value of innovation and reform in medical school anatomical education in the United States (Gregory et al, 2009;Hildebrandt, 2010;Sugand et al, 2010); the benefits of digital, and in some cases three-dimensional anatomy simulations to support undergraduate and postgraduate anatomy instruction (Hisley et al, 2008;Thakore and Mahon, 2008;Yip and Rajendran, 2008;Daruwalla et al, 2010), and the role of anatomy education in transmitting professional values to clinical students (Pawlina, 2006;Pearson and Hoagland, 2010). Researchers also have investigated the benefits of exploratory learning to teach clinical reasoning and to prepare anatomy students for future clinical work (Philip et al, 2008), the benefits of developing writing skills regarding anatomical knowledge as a preparation for communicating effectively with patients (Evans, 2008), the learning benefits of verbal discussions and oral presentations by students in anatomy education (Lake, 2001;Philip et al, 2008), and the need to identify and consider different learning styles of clinical students (Lujan and DiCarlo, 2006).…”