ÿþ<HTML> <HEAD> <TITLE> Dr. Mike Marshall's Pitching Book:&nbsp Chapter Sixteen</TITLE> </HEAD> <BODY> <CENTER><B> Coaching Baseball Pitchers </B></CENTER> <CENTER><B> By Michael G. Marshall, Ph.D. </B></CENTER> <CENTER><B> Copyright 2007 </B></CENTER><br> <CENTER><B> Chapter Sixteen:&nbsp&nbsp Forearm Joint </B></CENTER><br> <B>1.&nbsp Forearm Joint Bones </B><br><br> &nbsp&nbsp&nbsp&nbsp<B> a.&nbsp&nbsp Radius bone</B><br><br> &nbsp&nbsp&nbsp&nbsp In the forearm joint, the movement of the Radius bone is the forearm joint bone of interest.<br><br> &nbsp&nbsp&nbsp&nbsp The Annular Ligament wraps around the anterior surface of the head of the Radius bone.&nbsp As a result, the head of the Radius bone does not articulate with the Capitulum on the distal end of the Humerus bone.<br><br> &nbsp&nbsp&nbsp&nbsp Radial collateral ligaments secure the head of the Radius bone to the lateral side of the Humerus bone.<br><br> &nbsp&nbsp&nbsp&nbsp The Radial Tuberosity medially protrudes from the proximal end of the Radius bone just below the head of the Radius bone.<br><br> &nbsp&nbsp&nbsp&nbsp Proximally, oblique cords attach the Radius bone to the Ulna bone. All along the distal two-thirds of the Radius bone, Interosseous membranes attach the Radius bone to the Ulna bone.<br><br> &nbsp&nbsp&nbsp&nbsp The Radius bone rotates toward and away from the non-rotating Ulna bone.&nbsp Therefore, forearm joint actions only include whether the Radius bone rotates toward or away from the Ulna bone.<br><br> &nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp<B> 1)&nbsp Anterior Surface </B><br><br> &nbsp&nbsp&nbsp&nbsp The anterior surface of the Radius bone has two bony landmarks.<br><br> 01.&nbsp The head of the Radius bone lies at the proximal (elbow) end of the Radius bone and loosely articulates with the Capitulum of the Humerus bone.<br> 02.&nbsp From just below the head of the Radius bone, the Radial Tuberosity protrudes medially from the shaft of the Radius bone.<br><br> &nbsp&nbsp&nbsp&nbsp The anterior surface of the Radius bone has two tendon attachments.<br><br> 01.&nbsp The two heads of the Biceps Brachii muscle combine into a common tendon that attaches to the Radial Tuberosity of the shaft of the Radius bone.<br> 02.&nbsp The tendon of the Pronator Quadratus muscle attaches to the anterior surface f the distal one-fifth of the Radius bone.<br><br> &nbsp&nbsp&nbsp&nbsp The anterior surface of the Radius bone has no areas from which muscles arise.<br><br> &nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp<B> 2)&nbsp Posterior Surface </B><br><br> &nbsp&nbsp&nbsp&nbsp The posterior surface of the Radius bone has no bony landmarks.<br><br> &nbsp&nbsp&nbsp&nbsp The posterior surface of the Radius bone has, share three tendon attachments laterally with anterior surfaces.<br><br> 01.&nbsp The tendon of the Supinator muscle attaches to the proximal one-quarter of the lateral side of the posterior surface of the Radius bone.<br> 02.&nbsp The tendon of the Pronator Teres muscle attaches to the mid-shaft of the lateral side of the posterior surface of the Radius bone.<br> 03.&nbsp The tendon of the Brachioradialis muscle attaches to the lateral side of the posterior surface of the distal end of the Radius bone.<br><br> &nbsp&nbsp&nbsp&nbsp The posterior surface of the Radius bone has and no areas from which muscles arise.<br><br> &nbsp&nbsp&nbsp&nbsp<B> b.&nbsp Ulna Bone</B><br><br> &nbsp&nbsp&nbsp&nbsp With regard to the actions of the forearm joint, the Ulna bone does not move.&nbsp This means that, with regard to the forearm joint, we consider the Ulna bone as completely stationary.&nbsp The Ulna bone only moves with regard to the elbow joint.<br><br> &nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp<B> 1)&nbsp Anterior Surface </B><br><br> &nbsp&nbsp&nbsp&nbsp The anterior surface of the Ulna bone has two bony landmarks.<br><br> 01.&nbsp The Coronoid Process anteriorly protrudes from the proximal (elbow) end of the Ulna bone.<br> 02.&nbsp The Styloid Process posteriorly protrudes from the distal (wrist) end of the Ulna bone.<br><br> &nbsp&nbsp&nbsp&nbsp The anterior surface of the Ulna bone has one tendon attachment.<br><br> 01.&nbsp The tendon of the Brachialis muscle attaches to Coronoid Process of the Ulna bone.<br><br> &nbsp&nbsp&nbsp&nbsp The anterior surface of the Ulna bone has two areas from which primary pitching muscles arise.<br><br> 01.&nbsp Flexor Digitorum Profundus muscle arises from the proximal two-thirds of the Ulna bone.<br> 02.&nbsp The Pronator Quadratus muscle arises from lines on the distal one-quarter of the Ulna bone.<br><br> &nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp<B> 2)&nbsp Posterior Surface </B><br><br> &nbsp&nbsp&nbsp&nbsp The posterior surface of the Ulna bone has one bony landmark.<br><br> 01.&nbsp The Olecranon Process lies at the proximal (elbow) end of the Ulna bone.<br><br> &nbsp&nbsp&nbsp&nbsp The posterior surface of the Ulna bone has two tendon attachments.<br><br> 01.&nbsp The three heads of the Triceps Brachii muscle form a common tendon that attaches to the Olecranon Process of the Ulna bone.<br> 02.&nbsp The tendon of the Anconeus muscle attaches to the proximal one-fifth of the Ulna bone.<br><br> &nbsp&nbsp&nbsp&nbsp The posterior surface of the Ulna bone has and one area from which a muscle arises.<br><br> 01.&nbsp The Supinator muscle arises from the medial surfaces of the proximal end of the Ulna bone.<br><br> <B>2.&nbsp Forearm Joint Kinesiological Actions </B><br><br> &nbsp&nbsp&nbsp&nbsp The movement of the Radius bone relative to the fixed Ulna bone defines the kinesiological actions of the forearm joint.&nbsp The Radius bone either rotates toward the Ulna bone or rotates away from the Ulna bone.<br><br> 1.&nbsp Forearm Joint Pronation:&nbsp When muscles contract that rotate the Radius bone toward the Ulna bone.<br> 2.&nbsp Forearm Joint Supination:&nbsp When muscles contract that rotate the Radius bone away from the Ulna bone.<br><br> <B>3.&nbsp Forearm Joint Muscles </B><br><br> &nbsp&nbsp&nbsp&nbsp At one end, forearm joint muscles attach to the Radius bone.&nbsp At the other end, they can attach to the Scapula bone, the Humerus bone or the Ulna bone.<br><br> &nbsp&nbsp&nbsp&nbsp<B> a.&nbsp Biceps Brachii<br><br></B> &nbsp&nbsp&nbsp&nbsp The two tendons of the Biceps Brachii muscle form a common tendon that attaches to the Radial tuberosity of the Radius bone and to the supraglenoid fossa and coracoid process of the Scapula bone.&nbsp Therefore, when the Biceps Brachii muscle contracts, these structures move closer together.&nbsp This means that the Biceps Brachii muscle flexes the Shoulder Joint, indirectly flexes the Elbow Joint and supinates the Forearm Joint.<br><br> &nbsp&nbsp&nbsp&nbsp Because, during the deceleration phase of the baseball pitching motion, baseball pitchers must prevent the olecranon process of their Ulna bone from slamming into its olecranon fossa, after the Triceps Brachii muscle stops extending the pitching elbow, the Biceps Brachii muscle flexes the Ulna bone.<br><br> &nbsp&nbsp&nbsp&nbsp<B> b.&nbsp Brachioradialis<br><br></B> &nbsp&nbsp&nbsp&nbsp The tendon of the Brachioradialis muscle attaches to the lateral side of the Radial Styloid process of the Radius bone and to the lateral supracondylar ridge of the Humerus bone.&nbsp Therefore, when the Brachioradialis muscle contracts, these structures moves closer together.&nbsp This means that the Brachioradialis muscle flexes the Elbow Joint and supinates the Forearm Joint.<br><br> &nbsp&nbsp&nbsp&nbsp Because, during the deceleration phase of the baseball pitching motion, baseball pitchers must safely return the pitching forearm to its normal resting position, the Brachioradialis muscle supinates the Radius bone.<br><br> &nbsp&nbsp&nbsp&nbsp Because, during the deceleration phase of the baseball pitching motion, baseball pitchers must prevent the olecranon process of their Ulna bone from slamming into its olecranon fossa, after the Triceps Brachii muscle stops extending the pitching elbow, the Brachioradialis muscle indirectly flexes the Ulna bone.<br><br> &nbsp&nbsp&nbsp&nbsp<B> c.&nbsp Pronator Quadratus<br><br></B> &nbsp&nbsp&nbsp&nbsp The Pronator Quadratus muscle attaches to the distal one-fourth of the lateral side of the posterior surface of the Radius bone and to distal one-fourth of the lateral side of the posterior surface of the Ulna bone.&nbsp Therefore, when the Pronator Quadratus muscle contracts, these structures move closer together.&nbsp This means that the Pronator Quadratus muscle flexes pronates the Forearm Joint.<br><br> &nbsp&nbsp&nbsp&nbsp Because, during the acceleration phase of the baseball pitching motion, baseball pitchers must powerfully pronate the forearm joint, the Pronator Quadratus muscle pronates the Radius bone.<br><br> &nbsp&nbsp&nbsp&nbsp<B> d.&nbsp Pronator Teres<br><br></B> &nbsp&nbsp&nbsp&nbsp The Pronator Teres muscle attaches to the lateral surface of the middle one-third of the Radius bone and to the supracondylar ridge of the Humerus bone.&nbsp Therefore, when the Pronator Teres muscle contracts, these structures move closer together.&nbsp This means that the Pronator Teres muscle flexes the Elbow Joint and pronates the Forearm Joint.<br><br> &nbsp&nbsp&nbsp&nbsp Because, during the acceleration phase of the baseball pitching motion, baseball pitchers must powerfully pronate the forearm joint, the Pronator Teres muscle pronates the Radius bone.<br><br> &nbsp&nbsp&nbsp&nbsp Because, during the deceleration phase of the baseball pitching motion, baseball pitchers must prevent the olecranon process of their Ulna bone from slamming into its olecranon fossa, after the Triceps Brachii muscle stops extending the pitching elbow, the Pronator Teres muscle flexes the Ulna bone.<br><br> &nbsp&nbsp&nbsp&nbsp During the 1974 National League championship season, Los Angeles Dodger pitcher Tommy John suffered a severe pitching elbow injury.&nbsp To promote sweating, Tommy wore a rubber jogging jacket.&nbsp I arrived at Dodger Stadium early two weeks prior to Tommy s injury and saw Tommy jogging in his rubber jacket.&nbsp I checked Tommy s Pronator Teres muscle.&nbsp Even when Tommy was not pronating his forearm, his Pronator Teres muscle remained contracted.<br><br> &nbsp&nbsp&nbsp&nbsp Sweat contains higher concentrations of potassium electrolytes than body fluids.&nbsp Therefore, sweating reduces the amount of potassium available to the nerve cells.&nbsp The Potassium/sodium pump in nerve cells balances nerve conductions and relaxations.&nbsp Therefore, when athletes have low potassium concentrations, their motor nerves continue to stimulate muscle contractions, that is, the muscles that these motor nerves serve cramp.&nbsp I attributed Tommy s Pronator Teres tauntness to potassium insufficiency.&nbsp Unfortunately, Tommy was having an outstanding season and continued his training routine.<br><br> &nbsp&nbsp&nbsp&nbsp Two weeks later, when he threw a pitch to a Montreal Expo batter, Tommy s pitching arm buckled.&nbsp The pitch bounced halfway to home plate.&nbsp After his next throw also bounced halfway to home plate, he walked straight to me and said,  You were right. <br><br> &nbsp&nbsp&nbsp&nbsp I went with TJ the training room and examined his arm.&nbsp Because the Pronator Teres, Flexor Carpi Radialis, Palmaris Longus, Flexor Carpi Ulnaris and the portion of his Flexor Digitorum Superficialis muscles formed a ball in the middle of the anterior surface of his pitching forearm, I determines that the attachments of these muscles had torn loose from the medial epicondyle of his Humerus bone.<br><br> &nbsp&nbsp&nbsp&nbsp When I applied sideways pressure to the inside of his pitching elbow, where the Ulnar Collateral Ligament attaches the medial epicondyle of his Humerus bone to the coronoid process of his Ulna bone, these two bones moved apart.&nbsp Clearly, Tommy had ruptured his Ulnar Collateral Ligament.&nbsp I told Tommy that he had seriously injured his pitching elbow.<br><br> &nbsp&nbsp&nbsp&nbsp Nevertheless, the next day, when I arrived at Dodger Stadium, I found TJ tossing a baseball to a catcher in the home bullpen.&nbsp I immediately grabbed TJ and took him to the Bill Buhler, the Dodger trainer and I explained Tommy's problem.&nbsp Fortunately, Frank Jobe, the team orthopedic surgeon, later confirmed my diagnosis and did corrective surgery.<br><br> &nbsp&nbsp&nbsp&nbsp <B>e.&nbsp Supinator<br><br></B> &nbsp&nbsp&nbsp&nbsp The tendon of the Supinator muscle attaches to the lateral side of the anterior surface of the proximal one-third of the Radius bone and to the lateral epicondyle of the Humerus bone, to the Annular Ligament of the head of the Radius bone and to the Supinator Crest and Fossa of the Ulna bone.&nbsp Therefore, when the Supinator muscle contracts, these structure move closer together.&nbsp This means that the Supinator muscle supinates the Forearm Joint.<br><br> &nbsp&nbsp&nbsp&nbsp Because, during the deceleration phase of the baseball pitching motion, baseball pitchers must safely return the pitching forearm to its normal resting position, the Supinator muscle supinates the Radius bone.<br><br> <B>4.&nbsp The Kinesiological Actions of the Forearm Joint During the Marshall Baseball Pitching Motion</B><br><br> &nbsp&nbsp&nbsp&nbsp During the acceleration phase of the Marshall baseball pitching motion, to prevent the olecranon process of their pitching elbow from slamming into its fossa, baseball pitchers need to powerfully mioanglosly pronate their pitching forearm.<br><br> &nbsp&nbsp&nbsp&nbsp During the deceleration phase of the Marshall baseball pitching motion, to safely decelerate and stop the powerful pronation of their pitching forearm through release, baseball pitchers need to powerfully plioanglosly supinate their pitching forearm.&nbsp Remember, baseball pitchers can only pronate their pitching forearm as powerfully as the muscles that supinate their pitching forearm allow.<br><br> <hr><br> <CENTER><A HREF="FreeCoachingBaseballPitchersBook.html"> Free Coaching Baseball Pitchers Book!!! </A>&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp&nbsp<A HREF="ChapterSeventeen.html"> Chapter Seventeen </A><br> </CENTER> </BODY> </HTML>