A Literature Review of the Morphological Variability in the Intrinsic Muscles of the Foot: Traps Awaiting Clinicians during Ultrasound.

Purpose: Like other muscular compartments of the human body, the intrinsic muscles of the foot present considerable morphological variability. The aim of this review was to present variations that can potentially cause problems during surgery but might be detected during an ultrasound examination. Materials and methods: PubMed was searched for relevant articles. The identified papers were listed, and citation tracking was performed. Results: Even though lower limb structure is well studied, the variations associated with the intrinsic muscles of the foot and their related ultrasound examination are not. Conclusions: The muscles and tendons of the foot demonstrate similar degrees of variance as other regions of the human body; however, this subject is not as widely covered in the literature. Further ultrasound studies are needed to build awareness of morphological variability in this region, as the findings could prevent misdiagnosis.

Accessory thoracic muscles in human fetuses.

BACKGROUND: Typically, the anterior thoracic wall musculature is composed of the pectoralis major and pectoralis minor. Embryologically, these two muscles are originated from a common pectoral muscle mass; therefore, disruption of the normal development and differentiation could give rise to an aberrant or accessory muscle. The main aim of this study is to demonstrate and classify the accessory muscles of the pectoralis region in human fetuses. MATERIAL AND METHODS: Fifty spontaneously aborted human fetuses (25 male and 25 female, 100 sides) aged 18-38 weeks of gestation at death, and fixed in 10% formalin solution were examined. Following parental approval, the fetuses were donated to the Medical University anatomy program. The pectoralis major and minor muscle's morphology, the possible occurrence of accessory muscles of pectoral region and its morphology, their origins, and insertions, as well as the morphometric details, were assessed. RESULTS: The pectoralis major and minor were bilaterally found in all fetuses (100 cases). The accessory muscles of pectoral region were found in 16 cases (16%), and four types were differentiated. The Pectoralis Quartus muscle was the most common type of accessory muscles found in this study and occurred in 8 cases. The axillary arch muscle was observed in 3 cases. The chondrocoracoideus muscle was observed in 3 cases. The sternalis muscle occurred in 2 cases, and one of them was bifurcated. CONCLUSIONS: The thoracic region is characterized by a large amount of morphological variations, which are observed not only in adult population, but also among human fetuses. The pectoralis quartus was the most frequent variation in this study. Accessory structures like sternalis muscle, chondrocoracoideus muscle, pectoralis quartus muscle, or axillary arch muscle may have clinical implications, and knowledge about them is very useful for clinicians, especially plastic surgeons, thoracic surgeons, and orthopedics.

An unusual occurrence of a four-headed psoas major: a case report.

BACKGROUND: While many structures within the human body demonstrate anatomical variations, this is not typically the case for the iliopsoas muscle complex. However, the present paper describes a case of an anomalous psoas major composed of four different muscular heads in a 78-year-old male cadaver. MATERIALS AND METHODS: During a routine dissection of the right posterior abdominal wall, an unusual psoas major was observed, measured and photographed. RESULTS: The psoas major was found to possess four muscular heads, otherwise the anatomy of the wall was normal. CONCLUSIONS: The presence of so many heads could interfere with the functions of the psoas major muscle. Therefore this anatomical variation merits further study.

A three-headed psoas major muscle: a case report.

BACKGROUND: Multiple anatomical variations, from anomalous courses to additional structures, have been reported in muscles from different compartments of the human body. We report an extremely rare case of a psoas major muscle presenting as a three-headed structure with variable morphology. MATERIALS AND METHODS: During a routine dissection of the posterior abdominal wall of a 82-year-old male cadaver, an anomalous PM muscle with supernumerary head was identified, photographed and subjected to further measurement. RESULTS: Although the anatomy of the dissected posterior abdominal wall structures was typical, a three-headed psoas major muscle composed of superficial, intermediate and deep heads was identified. CONCLUSIONS: It is important to be aware of morphological variability of muscles, especially those considered to be constant, since an anomalous structure might interfere not only with their functions, but also lead to further clinical consequences.

The double-headed accessory iliacus muscle: a case report.

PURPOSE: Numerous accessory muscles are present in the human body, many of which are clinically significant. We present a case of an anomalous accessory iliacus composed of two heads, whose occurrence and anatomical location indicate a high probability of causing femoral nerve compression. METHODS: During a routine dissection of the posterior abdominal wall of a xx-year-old cadaver, a double headed accessory muscle was noted, measured and photographed. RESULTS: In addition to the normal anatomy of dissected structures from the posterior abdominal wall, an accessory iliacus muscle composed of superficial and deep heads was identified. In addition, the inferior roots of the divided femoral nerve located between the heads was found to follow an unusual course. CONCLUSIONS: It is important to be aware of morphological variability around structures such as double-headed accessory iliacus muscle presented in this study, due to their association with neurovascular bundles and hip joint. The reported atypical morphology is not widely known in the literature but might be of great clinical significance, therefore knowledge of such variability might be regarded in order to diagnose properly and introduce accurate treatment.

The morphological variability of the pelvic girdle muscles: a potential trap during ultrasound.

BACKGROUND: The muscles present in the pelvic girdle compartment demonstrate clinically significant anatomical variation regarding both their site of attachment and additions, such as accessory heads, muscles or tendinous slips. Many of those variations might be considered potential traps during ultrasound examination that may result in misdiagnosis. The aim of this study was to raise awareness of such possibility. MATERIALS AND METHODS: A comprehensive search for morphological variations was performed in PubMed and NIH. Relevant papers were listed and citation tracking was accomplished. RESULTS: Although several anatomical variations of pelvic girdle muscles have been presented, few studies have examined their relevance in ultrasound imaging. CONCLUSIONS: The morphological variability of the pelvic girdle muscles does not vary from such incidence in other regions of the human body; however further ultrasound studies are needed of the numerous morphological variants that can be found in this region.

Morphological variability of the leg muscles: potential traps on ultrasound that await clinicians.

BACKGROUND: Although muscles and their tendons are not considered the most morphologically variable structures, they still manifest a substantial diversity of variants. The aim of this study is to increase awareness of some of the many possible variants found during ultrasound imaging of one lower limb compartment, the leg, that could potentially mislead clinicians and lead to misdiagnosis. MATERIALS AND METHODS: PubMed was used for a comprehensive literature search for morphological variations. Relevant papers were included, and citation tracking was used to identify further publications. RESULTS: Several morphological variants of muscles of the leg have been described over many years, but this study shows that the occurrence of further variations in ultrasound imaging requires further investigations. CONCLUSIONS: The incidence of additional structures including muscles and tendons during ultrasound examination can cause confusion and lead to misinterpretation of images, misdiagnosis, and the introduction of unnecessary and inappropriate treatments.