BACKGROUND: Popeye deformity is common after rupture of the biceps muscle's long head tendon. Herein, we report on histological changes in biceps brachii muscles following tenotomy of the long head biceps tendon. METHODS: Twelve Sprague-Dawley rats (12-week-old) underwent tenotomy of the long head biceps tendon in the right shoulder. At postoperative weeks 4, 7, and 10, the operative shoulders were removed by detaching the biceps brachii muscle from the glenoid scapula and humerus; the opposite shoulders were removed as controls. H&E staining was performed to elucidate histological changes in myocytes. Oil-red O staining was performed to determine fatty infiltration. Myostatin antibody immunohistochemistry staining was performed as myostatin is expressed by skeletal muscle cells during myogenesis. RESULTS: H&E staining results revealed no changes in muscle cell nuclei. There were no adipocytes detected. Compared with that of the control biceps, the cross-sectional area of the long head biceps was significantly smaller (p=0.00). Statistical changes in the total extent of the 100 muscle cells were significant (p=0.00). Oil-red O staining revealed no fatty infiltration. Myostatin antibody immunohistochemical staining revealed no significant difference between the two sides. CONCLUSIONS: Muscular changes after tenotomy of the long head biceps included a decrease in the size of the individual muscle cells and in relative muscle mass. There were no changes observed in muscle cell nuclei and no fatty infiltration. Moreover, there were no changes detected by myostatin antibody immunohistochemistry assay.
Adipocytes ; Animals ; Congenital Abnormalities ; Head ; Humerus ; Immunohistochemistry ; Models, Animal ; Muscle Cells ; Muscle Development ; Muscle, Skeletal ; Muscles ; Myostatin ; Rats ; Rats, Sprague-Dawley ; Rupture ; Scapula ; Shoulder ; Tendons ; Tenotomy

Rhabdomyomatous mesenchymal hamartoma is a rare skin lesion composed of a haphazard arrangement of skeletal muscle, adipocytes, and collagen. Lesions usually present as a solitary sessile papule or nodule on the head and neck in childhood. The etiology of this skin lesion is not clear, but it is thought to be caused by a migration error of the embryonic mesodermal tissues or a genetic defect predisposing to the formation of hamartoma. It may occur as part of Delleman syndrome or congenital malformations like thyroglossal duct cysts, low set ears, and sclerocornea. Herein, we present two cases of rhabdomyomatous mesenchymal hamartoma, including a 20-year-old man who had two asymptomatic erythematous papules on the chin since childhood and a 58-year-old woman with an asymptomatic solitary erythematous sclerotic plaque on the chin for 2 years. Histopathologically, the lesions exhibited normal epidermis, and mature striated muscle fibers arranged randomly within the dermis. Physical examination revealed no congenital abnormalities.
Adipocytes ; Chin ; Collagen ; Congenital Abnormalities ; Dermis ; Ear ; Epidermis ; Female ; Hamartoma* ; Head ; Humans ; Mesoderm ; Middle Aged ; Muscle, Skeletal ; Muscle, Striated ; Neck ; Physical Examination ; Skin ; Thyroglossal Cyst ; Young Adult

During imaging studies or surgical procedures, anomalous forearm and wrist muscles are occasionally encountered. Among them, the flexor carpi radialis brevis is very rare. Because the trend is growing toward treating distal radius fractures with volar plating, the flexor carpi radialis brevis is worth knowing. Here, we report two cases with a review of the literature.
Female ; Forearm/*abnormalities ; Fractures, Comminuted/surgery ; Humans ; Middle Aged ; Muscle, Skeletal/*abnormalities ; Radius Fractures/surgery ; Ulna Fractures/surgery ; Wrist/*abnormalities

Anatomical variations are typically more common in the extensor compartment of the forearm, but uncommon in the flexor compartment. The presence of such anatomical anomalies is not usually noticed until the normal functions of an individual become hindered, or when these anomalies become a surgical problem. During routine dissection curriculum, we encountered a rare finding of bilateral Gantzer muscles in a cadaver. We describe the relationship between the Gantzer muscle and anterior interosseous nerve syndrome.
Cadaver ; Diagnosis, Differential ; Dissection ; Forearm ; abnormalities ; anatomy & histology ; innervation ; Humans ; Median Nerve ; anatomy & histology ; Models, Anatomic ; Muscle, Skeletal ; abnormalities ; anatomy & histology ; innervation

The anomalous orientation of musculature of the first dorsal fibro-osseous compartment of the wrist is clinically relevant to De Quervian's stenosing tenosynovitis and reconstructive surgeries. Split insertion of the abductor pollicis longus (APL) is commonly found in chimpanzees, gorillas and gibbons. A comparable identical pattern of anomalous slips in humans is of anthropological and phylogenetic importance and could be a result of atavism. This case report describes an unusual fused muscle belly of the APL and extensor pollicis brevis (EPB), which split into three slips--medial, intermediate and lateral. Further, the medial slip was seen to divide into two tendons, inserting on the base of the first metacarpal along with the intermediate slip. The lateral slip divided into three tendons, inserting into the base of the proximal phalanx, base of the first metacarpal and abductor pollicis brevis muscle. The fusion and unusual insertion pattern of the APL and EPB merits documentation for reconstructive procedures such as tendon transfer and interposition arthroplasty.
Arthroplasty ; Cadaver ; Female ; Humans ; Middle Aged ; Muscle, Skeletal ; abnormalities ; anatomy & histology ; Phylogeny ; Tendons ; abnormalities ; anatomy & histology ; physiopathology ; Wrist ; abnormalities ; anatomy & histology

A bilateral gastrocnemius tertius muscle and a unilateral accessory soleus muscle were encountered during the routine educational dissection studies. The right gastrocnemius tertius muscle consisted of one belly, but the left one of two bellies. On the left side, the superficial belly of the gastrocnemius tertius muscle had its origin from an area just above the tendon of the plantaris muscle, the deep belly from the tendon of the plantaris muscle. The accessory soleus muscle originated from the posteromedial aspect of the tibia and soleal line of the tibia and inserted to the medial surface of the calcaneus. On the right side, the gastrocnemius tertius muscle had its origin from the lateral condyle of the femur, and inserted to the medial head of the gastrocnemius muscle. The co-existence of both gastrocnemius tertius and accessory soleus muscle has not, to our knowledge, been previously reported.
*Abnormalities, Multiple ; Adult ; Humans ; Leg/*abnormalities ; Male ; Muscle, Skeletal/*abnormalities

The embryologic origin of the omohyoid muscle is different from that of the other neck muscles. A number of variations such as the absence of muscle, variable sites of origin and insertion, and multiple bellies have been reported. However, variations in the inferior belly of the omohyoid muscle are rare. There have been no reports of the combined occurrence of the omohyoid muscle variation with the appearance of the levator glandulase thyroideae muscle. Routine dissection of a 51-year-old female cadaver revealed a duplicated omohyoid muscle and the appearance of the levator glandulae thyroideae muscle. In this case, the two inferior bellies of the omohyoid muscle were found to originate inferiorly from the superior border of the scapula. One of the inferior bellies generally continued to the superior belly with the tendinous intersection. The other inferior belly continued into the sternohyoid muscle without the tendinous intersection. In this case, the levator glandulae thyroideae muscle appeared on the left side, which attached from the upper border of the thyroid gland to the inferior border of the thyroid cartilage. These variations are significant for clinicians during endoscopic diagnosis and surgery because of the arterial and nervous damage due to iatrogenic injuries. The embryologic origins of the omohyoid and levator glandulae thyroideae muscles may be similar based on the descriptions in the relevant literature.
Cadaver ; Female ; Humans ; Middle Aged ; Models, Anatomic ; Models, Biological ; Muscle, Skeletal/*abnormalities/pathology ; Neck Muscles/*abnormalities/*anatomy & histology

PURPOSE: To understand the modulation of genes by atrophy, differential expression of genes in normal and denervated skeletal muscle was investigated by DNA chip technology. MATERIALS AND METHODS: Sciatic nerve and femoral nerve were resected in right leg of rat to make the muscle atrophy model. Muscle tissues from the gastrocnemius of normal and denervated legs were homogenized and RNA were extracted. Dyes were labelled during reverse transcription and hybridization was done into the DNA chip which is consisted of about 5,000 probes. RESULTS: By statistical analysis, 39 genes were selected as differentially expressed genes by atrophy. 15 known genes up-regulated by atrophy were genes related to immune response, extracellular matrix, andsignal transduction in plasma membrane. 7 known genes down-regulated by atrophy were genes related to cell growth and proliferation, intracellular signal transduction, and energy metabolism. Some unknown gene functions were analysed by bioinformatics analysis and they were highly homologous genes with McKusick-Kaufman syndrome protein, ADP-ribosylation factor-like 4, and component X of pyruvate dehydrogenase complex. CONCLUSION: These results suggest that reduction of energy metabolism, activation of cholesterol exclusion, and changes on signal transduction pathway are involved in the process of atrophy by denervation in skeletal muscle of rat.
Abnormalities, Multiple ; Animals ; Atrophy ; Cell Membrane ; Chimera ; Cholesterol ; Coloring Agents ; Computational Biology ; Denervation ; Energy Metabolism ; Extracellular Matrix ; Femoral Nerve ; Gene Expression ; Heart Defects, Congenital ; Hydrocolpos ; Leg ; Muscle, Skeletal ; Muscles ; Muscular Atrophy ; Oligonucleotide Array Sequence Analysis ; Oxidoreductases ; Polydactyly ; Pyruvic Acid ; Rats ; Reverse Transcription ; RNA ; Sciatic Nerve ; Signal Transduction ; Uterine Diseases

INTRODUCTIONEthnic variations in the prevalence of absence of the palmaris longus (PL) are well known. Many techniques for clinically determining the presence of the PL have been described. Studies have also attempted to correlate its absence with other anatomical anomalies. However, most studies have been done in Caucasian populations.

MATERIALS AND METHODSThe presence of the PL was clinically determined in 329 normal Chinese men and women using the standard technique. In subjects with an absent PL, 4 other tests were performed to confirm absence and an Allen's test was done to assess the palmar arches. All subjects were examined for the presence of the flexor digitorum superficialis (FDS) to the little finger.

RESULTSThe overall prevalence of absence of the PL was 4.6%. All techniques were equally effective in determining the absence of the PL. There was no significant difference in its absence with regard to the body side or sex. Absolute deficiency of FDS to the little finger was seen in 6.4%. No correlation could be detected between the absence of the PL and FDS of the little finger.

CONCLUSIONSThe prevalence of absence of the PL and absence of FDS to the little finger in a Chinese population is much lower compared to previous reports in the literature. There is no association between absence of the PL and absence of the FDS to the little finger. Although all techniques of examining for the absence of the PL are equally effective, the method suggested by Mishra seems the best as it was easily understood by subjects and can be used even when thumb abduction is not possible.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Asian Continental Ancestry Group ; genetics ; Child ; China ; ethnology ; Female ; Fingers ; abnormalities ; Hand Deformities, Congenital ; complications ; epidemiology ; Humans ; Male ; Middle Aged ; Muscle, Skeletal ; abnormalities ; Prevalence ; Range of Motion, Articular ; genetics ; Singapore ; epidemiology ; Tendons ; abnormalities

An unusual variation creates interest among anatomists, but is a cause of concern among clinicians when it mimics a pathology. The sternalis muscle is one such variant of the anterior chest wall located subcutaneously over the pectoralis major, ranging from a few short fibers to a well-formed muscle. We observed a bilateral case, which was accompanied by an atypical presentation on the left side where a huge, bulky sternalis muscle was associated with the absence of the sternal fibers of the pectoralis major. The fibers arose as a lateral strip from the upper two-thirds of the body of the sternum and costal cartilages 2 through 6 with the intervening fascia and aponeurosis of the external oblique. The right sternalis was strap-like and was placed vertically over the sternal fibers of the pectoralis major, arising from the underlying fascia and aponeurosis of the external oblique. The sternalis muscles, on each side, converged into an aponeurosis over the manubrium that was continuous with the sternal heads of the right and left sternocleidomastoid muscle, respectively. This rare anomaly has puzzled radiologists and surgeons in confirming diagnosis, missing it all together or mistaking it for a tumor on mammography or CT scan. These findings prompted us to review its topography, development, and application in relation to the anterior chest wall.
Adult ; Human ; Male ; Muscle Fibers/pathology ; Muscle, Skeletal/*abnormalities/pathology ; *Thorax