Pronator teres

BACKGROUND: The flexor carpi ulnaris (FCU) and flexor digitorum superficialis (FDS) are thought to provide dynamic stability to the medial elbow, with a lesser contribution from the pronator teres (PT). HYPOTHESIS/PURPOSE: The purpose of this study was to determine if baseball pitchers with higher valgus elbow torque experience greater FCU and FDS strength loss. STUDY DESIGN: Controlled Laboratory Study. METHODS: A pilot study was performed to determine if middle and ring finger flexion strength tests preferentially activated the FCU and FDS versus the PT (10 men age 36±12 yr)...

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...

We measured the medial joint distance (MJD), activity of muscles involved in medial elbow-joint support, and grip strength, aiming to examine the supportfunction of muscles. MJD was measured in supinated and pronated positions of the forearm of 10 participants under three conditions: at rest (R), under valgus load on the elbow joint (L), and under valgus load on the elbow joint during the grip task (L-grip). Under the L-grip condition, electromyography was performed on flexor digitorum superficialis (FDS), pronator teres (PT), flexor carpi radialis (FCR), and flexor carpi ulnaris (FCU); subsequently, normalized integrated electromyograms (NIEMG) were calculated...

OBJECTIVE: To investigate the location and anatomical structure of "Shaochong"(HT9), "Shaofu"(HT8), "Shenmen"(HT7), "Lingdao"(HT4) and "Shaohai"(HT3) in the rabbit's forelimb. METHODS: Sixteen rabbits (half male and half female) were used in the present study. By referring to the national standards on the location of acupoints in the human body and the literature about the location of acupoints in the rabbit, and by using the method of comparative anatomy, the location and needling operation of the Five-shu acupoints of Shaoyin Heart Meridian on the rabbit's forelimb were defined, and these acupoints were needled and CT three-dimensional reconstruction were conducted...

Pronator syndrome (PS) is a rare type of peripheral compression neuropathy in which the median nerve becomes entrapped as it passes through the pronator teres muscle at the proximal forearm. We report an unusual case of acute PS in a 78-year-old patient on warfarin who presented after traumatic forearm injury with forearm swelling, pain, and paresthesias. After emergent nerve decompression and hematoma evacuation, the patient regained near complete recovery of median nerve function six months after diagnosis and treatment...

OBJECTIVE: To summarize the clinical characteristics, differential diagnosis, and treatment methods of finger flexion contracture caused by three kinds of forearm flexor diseases. METHODS: Between December 2008 and August 2021, 17 patients with finger flexion contracture were treated, including 8 males and 9 females, aged 5-42 years, with a median of 16 years. The disease duration ranged from 1.5 months to 30 years, with a median of 13 years. The etiology included 6 cases of Volkmann's contracture, all of which were flexion deformity of the 2nd to 5th fingers, accompanied by limitation of thumb dorsiflexion in 3 cases and limitation of wrist dorsiflexion in 3 cases; 3 cases of pseudo-Volkmann's contracture, including 2 cases of flexion deformity of middle, ring, and little fingers, and 1 case of flexion deformity of ring and little fingers; 8 cases of ulnar finger flexion contracture caused by forearm flexor disease or anatomical variations, all of which were flexion deformity of middle, ring, and little fingers...

Hereditary neuropathy with liability to pressure palsy (HNPP) is a rare autosomal dominant disease characterized by focal, recurrent, demyelinating peripheral neuropathies. It is caused by deletions of the gene encoding for peripheral myelin protein 22 (PMP22) on chromosome 17. While it may range widely, the most common clinical presentation is an acute, focal mononeuropathy with numbness or muscle weakness after trauma or compression. Diagnostic tools include electrophysiological studies, genetic tests and nerve biopsies...

There are very few descriptions of tendon transfers designed specifically to address the reconstruction of posterior interosseous nerve palsy (PINP). Unlike a radial nerve palsy (RNP), a patient with a PINP is able to extend their wrist but in radial deviation, because of the preserved innervation of the extensor carpi radialis longus (ECRL). Tendon transfers to restore finger and thumb extension in PINP have been extrapolated from tendon transfers to restore these functions in RNP, specifically using flexor carpi radialis, not flexor carpi ulnaris, so as not to further exacerbate the distinctive radial deviation deformity of the wrist...

The pronator teres muscle is a major dynamic stabilizer of elbow valgus stress during throwing. This study aims to investigate pronator teres muscle activation during breaking ball pitching in baseball pitchers. Twelve male college baseball players with more than eight years of baseball experience were included in this study. A wireless surface electromyography (EMG) system was used to measure the activation of the forearm muscles and record EMG data during fastball and curveball pitching. Peak pronator teres muscle activation during curveball pitching was greater than that during fastball pitching ( p = 0...

The harder the forearm flexor-pronator muscles (FPMs) relative to the ulnar collateral ligament (UCL), the less likely it is for UCL laxity to occur with repeated pitching. This study aimed to clarify what selective contraction of the forearm muscles makes FPMs harder relative to UCL. The study evaluated 20 elbows of male college students. Participants selectively contracted the forearm muscles in eight conditions under gravity stress. The medial elbow joint width and the strain ratio indicating tissue hardness of the UCL and FPMs during contraction were evaluated using an ultrasound system...

PURPOSE/HYPOTHESIS: The flexor-pronator mass of the forearm contributes dynamic stability to the medial elbow. Training this muscle group is essential for overhead athletes, however, there is lack of evidence supporting use of training exercises. The purpose of this study was to measure the extent of EMG activity of the flexor pronator musculature during two distinct forearm strengthening exercises using resistance bands. It was hypothesized that two exercises would elicit at least moderate level of muscle activity, but the activation would be different in the pronator versus the flexor muscles...

BACKGROUND: The pronator teres (PT) to extensor carpi radialis brevis (ECRB) tendon transfer reestablishes wrist extension. Occasionally, the PT periosteal extension is of suboptimal quality to support a strong transfer. In these instances, turnover lengthening techniques can increase usable tendon length. This study characterized the optimal length of tendon turnover and the effect of lengthening on transfer strength. METHODS: Twenty-seven cadaveric extensor tendons were lengthened using the turnover lengthening technique with 1-3 centimeters of tendon overlap...

Procyon cancrivorus and Nasua nasua are two procyonids with different evolutionary adaptations to use their thoracic limbs. Therefore, this study aimed to characterize the differences in the brachial plexus between both species. Five P. cancrivorus and five N. nasua cadavers were used to perform this investigation with the permission of the bioethics committee and environmental license. Gross dissections were performed on the cervical, pectoral, and thoracic limb regions to find the origin and distribution of the brachial plexus...

The myotome of a muscle is the basis for diagnosing spinal and peripheral nerve disorders. Despite its critical importance in clinical neurology, myotome charts presented in many textbooks, surprisingly, show non-negligible discordances with each other. Many authors do not even clearly state the bases of their charts. Studies that have presented with raw data regarding myotome identification are rather rare. A classic study in the 19th century that pursued the nerve course in cadavers still has a substantial influence on existing charts, despite its definite limitations...

A 48-year-old female was admitted to the authors' department due to hand weakness as a consequence of C8, T1 root injury. Eight months earlier, the patient had been treated by a pulmonary surgeon due to an expansive lesion near the apex of the right lung, which resulted in right lower brachial plexus palsy. Postoperative pathohistological findings indicated that the lesion was nerve schwannoma. The diagnostic process included physical examination, electromyoneurography, and MRI. A distal nerve transfer (pronator teres-anterior interosseus nerve [PT-AIN], supinator-posterior interosseus nerve [SUP-PIN]) was performed in order to restore hand function...

We aimed to clarify changes cross-sectional area (CSA) in flexor pronator muscles and the ulnar nerve (UN) in players with medial elbow pain between pitching phases. Forty-two male baseball players with and without medial elbow pain during throwing were included in this study. The players were divided into maximum external rotation (MER) and ball release (BR) groups according to the pitching phase in which pain was reported. The imaged region was the flexor digital profundus, flexor carpi ulnaris (FCU), flexor digitorum superficialis, and pronator teres muscles, as well as the UN...

Variations of the brachialis muscle are uncommon in the literature. During regular cadaveric dissection, we observed the unilateral presence of an accessory muscle in the front of the right arm of a female cadaver, taking its origin from the medial aspect of the brachialis and the adjacent intermuscular septum. The muscle belly descended downwards, crossed the neurovascular bundle in the cubital fossa and merged with the fibres of the pronator teres. There is no doubt regarding its significance in the etiogenesis of numerous compression syndromes due to its close topographical relationship with the neurovascular bundle...

BACKGROUND: Tendon and nerve transfers are used for functional reconstruction in cases of proximal radial nerve injury complicated by humeral fractures in patients who do not show functional recovery after primary nerve repair. The effectiveness of pronator teres (PT) nerve branch transfer to the extensor carpi radialis brevis (ERCB) nerve branch for wrist extension reconstruction was investigated and compared to the results of tendon transfer. METHODS: This study included 10 patients with proximal radial nerve injury, who did not show functional recovery after primary nerve repair at our hospital between April 2016 and May 2019...

PURPOSE: The purpose of this study is to characterize the division of the median nerve by the persistent median artery (PMA) and highlight the associated clinical implications. Penetration of the median nerve by the PMA is believed to cause compression of the median nerve and affect nerve conduction velocity. This paper explored whether the origin and the pattern of PMA dictate its ability to divide the median nerve. METHODS: Origin, and relationship of the PMA to the median nerve were documented in 60 cadavers donated to the Human Anatomy Program at UT Health San Antonio...

Tendon transfers can be tied too tight or too loose. Both impede good function after surgery. Performing tendon transfers without sedation and pain during the surgery and then watching the patient move the transfer have helped us adjust the tension more accurately. This method can be applied to complex transfers such as radial nerve palsy triple tendon transfers. We describe the technique and results of a triple tendon transfer using wide-awake local anesthesia no tourniquet in a patient with a high radial nerve palsy...