The Impact Of Anatomical Variation On Surgical Outcomes

Abstract

This is a comprehensive review on anatomical variations, highlighting their identification approaches, clinical significance, surgical outcomes and teaching strategies. Anatomical variation is known to be the presentation of the structure of the body with linguistical characteristics differences from those explained in different anatomy textbooks. Under normal occasion it doesn’t affect the structure’s ability to function normally. Nether the less, it may cause different clinical practice aspects. Therefore, precise understanding of typical anatomical differences in the treated area may enhance the results of clinical practice. On the flip side,

Anatomical variations are normally located during scheduled clinical practice and dissections, including surgical procedure and preoperative imagine.

This article will dive in depth on how anatomical variations impacts various surgical fields, this includes orthopedic, general, plastic surgeries and cardiovascular. It will also give explanations on technological advancement in artificial intelligence and preoperative imaging that support surgeons course through these challenges. Lastly, the study focus attention on the value of continuous anatomical research and education to better improve surgical outcomes.

Introduction

Surgical errors take hand in a significant burden to health systems nationwide. According to Oyebode (2013) A large proportion of this burden is a result of patient-related complexities, which include “difficult or unusual anatomy” otherwise referred to as anatomical variations. Kowalczyk and Majewski (2021) implies Anatomical variations are deviations from the typical arrangement of anatomical structures. These variations are present within populations, and no two individuals have exactly the same anatomy Saniotis and Henneberg (2021). Beser (2018) once said anatomical variation is likely the result of a combination of genetic and environmental factors interfering with the embryological development of anatomical structures, similar to what Cunningham (1898) once said. However, Cunningham (1898) and Sañudo et al (2003) said, such disruption is also the cause of pathological congenital abnormalities like structural cardiac defects and organ atresia. It is, therefore, crucial to differentiate an anatomical variation from other pathologic anomalies, as the previous does not result in a verifiable impairment in normal functioning.

Clinical attention is usually not warranted for anatomical variations. Georgiev (2017) and Smith (2021) both implies, because they may mimic sinister pathologies like malignancy, anatomical variations are more likely to affect patients indirectly by obscuring diagnosis or obstructing management. Saniotis and Henneberg M. (2021) acknowledged that Radiology is increasingly central to daily clinical practice and has made it easier to accurately identify anatomical variations. Heptonstall, Ali, and Mankad (2016) implies with approximately 62 million CT scans being obtained each year in the United States, anatomical variations are being detected much more frequently Żytkowski Tubbs et al. (2021), Smith (2021) and Royer (2018) all recalled stating clinicians without an adequate appreciation of anatomical variability could be misled by incidentally detected variants. As a result, needless medical procedures and additional research are sought, placing a burden on resources and, more significantly, compromising patient care.

Royer (2018) states anatomical variations can negatively impact surgical outcomes, and a proportion of the avoidable deaths in the United States are due to inadequate anatomy knowledge. Kowalczyk and Majewski (2021), Sañudo, Vázquez, and Puerta (2003), Estai and Bunt (2016) all said a study of malpractice claims from four US-based insurance companies found that 25% of claims were attributed to anatomical variations, Regenbogen, Greenberg, Studdert, et al. (2007), Leppäniemi, and Clavien (2013) stated that, despite a general underreporting of anatomy-related surgical complications, failure to identify variant anatomy in surgery not only affects patient safety but also incurs large litigation and malpractice claims.

Medical professionals and anatomists are both accountable for the lack of attention in anatomical variety in education. Bergman (2011), Moore (1989) thoughts where, this is because variant anatomy is frequently encountered in dissection sessions and clinical practice, yet very little effort has been made to address the neglect of anatomical variations in medical education. Willan and Humpherson (1999), Štrkalj (2014) clarifies the predominance of learning resources like plastic models, which almost exclusively depict ‘normal’ or ‘typical’ anatomy, also continues to foster the notion of the ideal, non-variant anatomy, especially when educators fail to clarify to students that the range of ‘normal’ is wide.

Moore. (1989) clarifies, it is concerning that anatomical variation has little to no role in medical education today. Perhaps educators have overlooked the fact that, as a result of greater access to developing imaging technology, future physicians would face even more anatomical variances than those discovered by past generations. Royer (2018), Willan and Humpherson. (1999) both agreed to the fact that currently, there is an appreciable gap in the literature regarding anatomical variation and medical education. Alraddadi. (2021) explains that the main purpose of this systematic review is to examine the representation of anatomical variation in medical education literature and delineate relevant themes. The insights from this review are likely to influence the status of educational practices and contribute to the evaluation of current anatomy curricula.

Literature Review:

Willan and Humpherson (1999) clarifies that the influence of anatomical variations on different aspects of clinical practice can be categorized into the predisposition to illness, symptomatology, clinical examinations, and treatment of patients, including surgery. Parikh, and Honeycutt et al. (2012) stated that, previous studies found that individuals with left coronary artery dominance have a higher risk of in-hospital mortality and myocardial reinfarction than those with right coronary artery dominance. Ghorbani, Forouzesh and Kazemifar (2012) clarifies that the anatomy of the vermiform appendix also showed variable positions, including pelvic (56%), subcecal (19%), retroileal (13%), retrocecal (7%), ectopic (4%), and pre-ileal (2%).

These differences could lead to serious complications including sepsis and perforation and could misdiagnose patients with acute appendicitis.

Rajapakse and Chang (2014) clarified a large body habitus can produce low-quality images in clinical examinations, affecting the accuracy of clinical interpretations of the images. Another rare anomaly that can be seen during the clinical investigation of the chest is the azygos lobe of the lung which was said by Pradhan, Sahoo et al. (2017), Sieber, Karcara, and Pant, (2014). It may be clinically confused with a bulla or abscess and was observed in 0.4% of chest radiographs. In Lippert and Pabst (1985), Surekha and Sudhir (2018) researches the routine clinical practice of measuring blood pressure may also interfere with the higher division of the brachial artery, which can occur in 20% of cases. The upper extremities frequently experience arterial fluctuation. Therefore, accurate knowledge of these variations may help prevent limb complications such as injury, thrombosis, gangrene, or even amputation of limbs stated by Gujar, Oza, Shekhawat et al. (2014).

 Furthermore, Ding, Wang et al. (2007) said that, a safe laparoscopic cholecystectomy requires accurate knowledge of the cystic artery anatomy variations. Vishnumaya, Bhagath et al. (2008) originally states, the cystic artery is a branch of the right hepatic artery, but it may also arise from other arteries, including the left hepatic artery, the hepatic artery proper, the common hepatic artery, the superior pancreaticoduodenal artery, the superior mesenteric arteries, or even the gastroduodenal artery.

Sinnatamby. (2011) explains about the pectoralis minor which also shows variable anatomy that is worth considering in clinical practice. The pectoralis minor is a significant anatomical landmark on the chest wall providing access to many related structures in the clavipectoral and axial regions. However, Hojo Nakashima, and Tsuruno. (1987), Asghar, Narayan et al. (2020) states the muscle shows several variations, including the origin and insertion of the attachment sites, muscle length (Lee, 2020), vasculature (Moriya 1993) and innervation (Murakami 2002). Hence, knowing the anatomical details of the pectoralis minor is essential for many clinical applications and surgical procedures such as pectoralis minor release and nerve block stated in as Hendrix, Hoyle, and Tokish. (2018) and Sedra. (2015) clarified.

Kowalczyk, and Majewski. (2021), explained in an attempt to increase awareness of anatomical variations in general surgery, Kowalczyk, and Majewski. (2021) discussed the variable anatomy that may influence the outcomes of common surgical procedures. The listed surgeries included cholecystectomy, inguinal hernia repair, hepatobiliary surgery, spleen, colon, thyroid, breast, axillary, pancreatic, and gastric surgery. They recommended closing this gap, usually cited as a technical error in surgical injuries, through introducing dissection courses and using preoperative imaging techniques. Therefore, accurate knowledge of the anatomical variations may improve the clinical practice outcomes.

• Cardiovascular System: Aortic arch abnormalities may make open-heart surgeries more difficult, and variations in the origin of the coronary arteries may impact treatments such as coronary bypass surgery (Loukas, Groat, and Khangura. 2017).
• Musculoskeletal System: Thoracic outlet syndrome, which affects orthopedic and vascular procedures, can be brought on by cervical ribs (Baptista-Silva et al., 2016). Tendon graft procedures may be impacted by differences in the locations of muscle attachments (Lee, Seong, and Lee. 2019).
• Neurological System: Brachial plexus variances affect nerve regeneration techniques, while differences in the Circle of Willis affect stroke treatment (Lasjaunias, Berenstein, and ter Brugge. 2018).
• Digestive System: Positional variations in the appendix effect laparoscopic appendectomies, while variations in the cystic artery affect gallbladder procedures (Singh, and Chauhan. 2022).
• Digestive System: Gallbladder operations are impacted by changes in the cystic artery, whereas laparoscopic appendix appendectomies are affected by positional modifications in the appendix (Singh, and Chauhan. 2022).

Identifying Anatomical Variations Approach

Willan, and Humpherson. (1999) stated, practitioners and anatomical scientists play a significant role in identifying anatomical variations. The typical traditional approach to identifying anatomical variations was through cadaveric dissection. On the other hand, during physical examinations, imaging studies, and surgical procedures, some of the differences were found in clinical practice. Furthermore, the literature demonstrated that the identification of any anatomical variations was aided by scientific study, including observational studies and evidence-based anatomy.

Several research that documented uncommon instances of anatomical changes found during standard laboratory dissections or surgical procedures were presented in the literature review. Benes. and Kachlik. (2021) reported two cases of variable branching of the musculocutaneous and median nerves found during a routine dissection course. Kim, Nam, and Kim. (2021) also presented a novel variation identified during routine dissection in which the posterior division of the femoral nerve was penetrated by the ascending branch of the lateral circumflex femoral artery. Preoperative medical scans helped Vigneshwaran, Muduly, Sultania et al. (2021) to identify double variations of a horseshoe kidney and an accessory renal artery in a challenging case of low rectal cancer planned for laparoscopic resection. In addition, during preoperative diagnosis of a living liver donor, Gündoğdu, and Kebapçı. (2021) observed an accessory right hepatic artery originating from the dorsal pancreatic artery and a middle hepatic artery arising from the pancreaticoduodenal artery. These preoperative observations of anatomical variations guided the surgeons to safe surgical resection of the cancer, and they searched for a new liver donor [Vigneshwaran (2021); Gündoğdu. (2021].

 However, Keser, Elshamy, Chen et al., (2021) noticed more significant results of anatomical variations are commonly reported through observational studies that inspect larger numbers of cadavers and medical images and outline their implications in health practice. A recent study done by Keser, Elshamy, Chen et al. (2021) assessed the challenges in using the posterior inferior cerebellar artery to the anterior inferior cerebellar artery bypass in 10 cadavers. The two arteries’ anatomical characteristics were assessed. Because of the morphological and parametric differences in both arteries, the bypass was not feasible. Famurewa, Ibitoye et al. (2018) placed another study examined the morphological anatomy of the sphenoid sinus using computerized tomography images of 320 adult patients. The findings showed several inter-sphenoid septa, varying lateral extensions, different forms of pneumatization, and the internal carotid artery protruding into the sphenoid sinus. Before undergoing any skull, base surgery utilizing the endoscopic endonasal transsphenoidal technique, it is crucial to recognize these variances to enhance the findings of reported anatomical variations.

Metodology

A detailed assessment of journal papers, case studies, and medical textbooks that detail anatomical variances and how they affect surgical operations served as the foundation for this investigation. The databases of surgical literature, PubMed, and Google Scholar were used to choose the sources. Priority was given to research on surgical complications and methods for reducing risk brought on by anatomical variances (Johnson, Smith, and Davis. 2021).

Surgery in General

 Variations in the cystic artery can complicate gallbladder surgery (cholecystectomy), resulting in bile duct damage or excessive bleeding (Yabunaka, Katsumata, and Yamamoto, 2020).  Likewise, when the appendix is in an uncommon position, like retrocecal positioning, appendectomies may be more difficult (Singh, and Chauhan, 2022).

 Changes in mesenteric artery branching patterns can drastically change surgical techniques in colorectal procedures.  Another issue with hepatobiliary surgeries is the presence of an abnormal right hepatic artery, as an incorrect ligation may result in severe liver failure (Moore,  Agur, and Dalley. 2020).

Neuro-surgery

 Procedures for removing brain tumors may be impacted by variations in the brain’s venous drainage, such as variations in the vein of Galen (Lasjaunias, Berenstein, and ter Brugge. 2018).  Furthermore, preoperative imaging is necessary for accurate intervention in spinal fixation procedures due to the influence of differences in spinal structures (Tubbs, Shoja, and Loukas. 2020).

 Surgery for Orthopedic Conditions

 Differences in femoral head size may impact hip replacement procedures and impact implant choice (Lee, Seong, and Lee. 2019).  Reconstruction techniques are affected by the existence or absence of auxiliary anterior cruciate ligaments (ACLs), which must be taken into account during knee ligament surgeries (Baptista-Silva et al., 2016).

Furthermore, differences in tendon location and congenital limb abnormalities affect prosthetic fittings and reconstructive treatments, highlighting the need for customized treatment approaches ( 2018). Giele, Cassell, and Smith.

Surgery for the Heart

 The risk of coronary bypass surgery may be increased by abnormal origins of the left major coronary artery (Loukas, Groat, and Khangura 2017).  The requirement for precise preoperative mapping is highlighted by the fact that aortic arch differences can change surgical methods in open-heart surgeries (Giele, Cassell, and Smith. 2018).  Sudden cardiac arrest has been associated with coronary abnormalities, underscoring the significance of early detection by angiography (Johnson, Smith, and Davis. 2021).

 Reconstructive and Plastic Surgery

 variances in median nerve branching impact the outcome of carpal tunnel release surgery, while variances in facial nerves can make reconstructive treatments more difficult (Moore, Agur, and Dalley 2020).  Personalized surgical planning is made possible by an understanding of these variances (Standring. 2021).

Technological Developments in Variation Recognition

• Preoperative Imaging: Due to their ability to visualize anatomical differences in real time, MRI, CT, and Doppler ultrasonography are now crucial tools for surgical planning (Giele et al., 2018).
• Organ 3D printing: Before performing surgery on patients, physicians can rehearse procedures using customized anatomical models (Tubbs, Shoja, and Loukas. 2020).
• Artificial Intelligence (AI): By using genetic and imaging data to forecast anatomical differences, machine learning systems can lower surgical errors (Johnson et al., 2021).

 In Conclusion

In conclusion, anatomical variation occurs frequently during dissection sessions and clinical practice.  Medical professionals must recognize these differences since they could alter the clinical practice regimen. Among the methods used to detect anatomical variations include physical examination, cadaveric dissection, evaluation of preoperative imaging and surgical operations.  The awareness of the anatomical variety may be raised by observational investigations, such as cadaveric dissection, medical image analysis, and evidence-based anatomy.  Medical schools frequently use dissection as a teaching technique to teach anatomy and relevant variation. The literature does, however, indicate a deficiency in educational research assessing how anatomical changes are learned and assessed.  In order to improve clinical practice, the current study suggests building a health informatics database to compile frequent anatomical variations. understanding of these differences and enhance the results of clinical treatment.  Lastly, additional study on the teaching and evaluation of anatomical differences in medical curricula is required.

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