Value of High-Frequency Ultrasound in the Diagnosis of Pronator Teres Syndrome / 中国医学科学院学报

Objective To investigate the clinical value of high-frequency ultrasound in the diagnosis of pronator teres syndrome (PTS). Methods The high-frequency ultrasound was employed to examine and measure the median nerve of the pronator teres muscle in 30 patients with PTS and 30 healthy volunteers (control group).The long-axis diameter (LA),short-axis diameter (SA) and cross-sectional area (CSA) of the median nerve were measured.The receiver operating characteristic curve of the median nerve ultrasonic measurement results was established,and the area under the curve (AUC) was calculated.The diagnostic efficiency of each index for PTS was compared with the surgical results as a reference. Results The PTS group showed larger LA[(5.02±0.50) mm vs.(3.89±0.41) mm;t=4.38,P=0.013],SA[(2.55±0.46) mm vs.(1.70±0.41) mm;t=5.19,P=0.009],and CSA[(11.13±3.72) mm2 vs.(6.88±2.68) mm2;t=8.42,P=0.008] of the median nerve than the control group.The AUC of CSA,SA,and LA was 94.3% (95%CI=0.912-0.972,Z=3.586,P=0.001),77.7% (95%CI=0.734-0.815,Z=2.855, P=0.006),and 78.8% (95%CI=0.752-0.821,Z=3.091,P=0.004),respectively.With 8.63 mm2 as the cutoff value,the sensitivity and specificity of CSA in diagnosing PTS were 93.3% and 90.0%,respectively. Conclusion High-frequency ultrasound is a practical method for diagnosing PTS,and the CSA of median nerve has a high diagnostic value.

Relaciones entre nervio mediano y musculo pronador redondo en la región cubital: implicancias anatomo-clínicas / Relationships between median nerve and the pronator teres muscle in the cubital region: anatomic and clinical implications

La intensa actividad muscular del antebrazo genera la necesidad de describir los posibles sitios de compresión de los nervios periféricos del miembro superior. En el caso del nervio mediano, uno de los sitios con mayor prevalencia de atrapamiento es cuando el nervio transita en el interior del canal del carpo. A este sitio debemos sumar la potencial compresión de este nervio en su paso entre las cabezas del músculo pronador redondo (PR). Esta compresión es caracterizada por paresias de músculos flexores de muñeca o algunos músculos de la eminencia tenar, signos a los que se pueden sumar parestesias y dolor en la mano. El objetivo del presente estudio fue describir la relación del nervio mediano con el músculo pronador redondo, para ello se utilizaron 30 antebrazos, de cadáveres formolizados, de individuos brasileños, adultos. Se encontró que en un 40% de los casos el nervio mediano atravesó la cabeza ulnar del músculo PR a lo que se sumó un caso en la cual la cabeza ulnar del músculo PR estuvo ausente, por lo cual, dicho nervio transitó posterior a la cabeza humeral del citado músculo. La clínica que se desarrolla a partir de un síndrome de compresión a este nivel está directamente vinculado a la distribución de los ramos que el nervio presenta proximal al sitio de la compresión. Asociado a estos hallazgos, resulta vital que para diagnosticar de manera óptima una compresión del nervio mediano es preciso descartar una compresión de este nervio en sitios proximales al canal del carpo.

Intense muscle activity of the forearm generates the need to describe the possible sites of compression of the peripheral nerves of the upper limb. For the median nerve one of the most prevalent sites of nerve entrapment is when the nerve travels within the carpal tunnel. To this we must add the potential compression of the nerve when it passes through the heads of the pronator teres muscle (PT). This compression is characterized by paresis of the wrist flexor muscles or some of the thenar, signs which can add to numbness and pain in the hand. The aim of this study was to describe the relation of the median nerve with the PT muscle. Thirty formolized forearms of adult Brazilian individuals were used. It was found that in 40% of cases the median nerve crossed the ulnar head PT muscle. In one case the ulnar head was absent. Due to this, the median nerve passed posterior to the humeral head of this muscle. The clinic that develops from compression syndrome at this level is directly linked to the distribution of the branches that the nerve presents proximal to the site of compression. Associated with these findings, it is vital for optimal diagnosis of the compression of median nerve to rule out compression of this nerve in proximal sites to the carpal tunnel.

Anomalous Branches of Median Nerve In The Arm.

Background: Dissection of right and left upper limbs and demonstration of the origin and the course ofmedian nerve. Result: Median nerve in the right upper limb is formed normally but it supplies brachialis muscle and both head of the biceps in the armwhich is anomalous. In the left arm of the patient the course and supply of median nerve is normal. Conclusion: The patient has unilateral anomalous supply of median nerve in the arm – this can result in trauma to this nerve while undergoing any surgery in right arm.

Variations of pronator teres muscle. A morphological study.

The muscles of shoulder girdle and elbow act together to position the hand accurately for manipulative functions. The superior extremity of man has undergone various modifications during evolution one of which is the lateral rotation of forelimbs at joints with pectoral girdle. The aim of the present study was to study the variations of pronator teres muscle. The present study was done on 60 upper limbs (56 Males and 4 Females) of embalmed adult human cadavers obtained from Deptt of Anatomy, Govt. Medical College Patiala. The humeral head of PT was found in all the cases, while Ulnar head was present in 52(86.7%) cases. The Humeral head was muscular in all the cases. The Ulnar origin was muscular in 15 cases (28.84%), tendinous in 7 cases (13.46%) & mixed in 30 cases (57.7%). In 2 (3%) cases there was double humeral head and the median nerve was passing between them. In 3cases (5%) there was high origin of humeral head of Pronator teres from medial intermuscular septum. Anatomy instructors and health professionals should be aware of the common variations in muscles and tendons of the forearm, not only for their academic interest but also for their clinical and functional implications.

Early Surgical Treatment of Pronator Teres Syndrome

We report a rare case of pronator teres syndrome in a young female patient. She reported that her right hand grip had weakened and development of tingling sensation in the first-third fingers two months previous. Thenar muscle atrophy was prominent, and hypoesthesia was also examined on median nerve territory. The pronation test and Tinel sign on the proximal forearm were positive. Severe pinch grip power weakness and production of a weak "OK" sign were also noted. Routine electromyography and nerve conduction velocity showed incomplete median neuropathy above the elbow level with severe axonal loss. Surgical treatment was performed because spontaneous recovery was not seen one month later.

Presence of Additional Head of Pronator Teres Muscle and Associated Neurovascular Variations: A Rare Case Report

Arm is a site for frequent injuries and it is involved in many surgical procedures. Variations in the arm have immense clinical significance. During the dissection of a right upper limb, brachial artery was found to divide into radial and ulnar arteries, 3cm above the inter-epicondylar plane. The ulnar artery and the median nerve were then passing through a tunnel formed by an extensive additional humeral head of the pronator teres muscle. Two centimetres long fibromuscular tunnel formed by the humeral head of the pronator teres was found to arise from the medial intermuscular septum and also from the fibrous arch form the shaft of the humerus to the medial intermuscular septum. In the same cadaver, the superior ulnar collateral artery was found to arise from the profunda brachii artery which is otherwise a branch of the brachial artery. Accurate knowledge of these variation patterns is of considerable clinical significance in conduct of surgeries of arm, fracture management of humerus and diagnosis of various compressive neuropathies.

Partial Tear of Pronator Teres Muscle in Amateur Golfer: A Case Report / 대한스포츠의학회지

Golf is low demanded activity and becoming more popular. But it often occur problems in back, shoulder, elbow and wrist. Golf injuries in professional golfer are related overuse and frequency, while in amateur are related wrong swing technique. Also muscle activities in swing are different between professional and amateur. We report partial tear of pronator teres in middle aged amateur golfer with literatures.

Topographic Anatomy of the Median Nerve and the Pronator Teres and the Flexor Digitorum Superficialis Muscles / 대한해부학회지

The pronator teres syndrome can occur when the median nerve is compressed by the adjacent structures in the proximal forearm. The pronator teres and the flexor digitorum superficialis muscles have been suggested to contribute to this syndrome. This study was performed to clarify the topographical relationship among the median nerve, the pronator teres muscle and the flexor digitorum superficialis muscle in 55 Korean adult cadavers (100 sides of arms). The two heads of the pronator teres muscle met at the point of 61.3 mm distal to the biepicondylar line and inserted to the radius at the point of 141.5 mm distal to the line. The ulnar side of its ulnar head was muscular in 8%, tendinous in 70%, and mixed in 20%. The radial side of its humeral head was muscular in 53%, tendinous in 14%, and mixed in 33%. The median nerve was completely covered by the pronator muscle within 26.5 mm from the biepicondylar line and entered between the two heads of the pronator muscle at 54.2 mm from the line and exited it after running 25.5 mm. The most distal part of the musculotendinous arch of the flexor digitorum superficialis muscle was located at the average 80.9 mm from the biepicondylar line. The distalmost radial head of the flexor digitorum superficialis muscle originated from the distal point of the pronator teres insertion in 28.6%, distal to that point in 54.3%, and proximal to that point in 14.3%.