The Deep Front Arm Line is one of several Fascial Lines proposed by Thomas Myers (SOURCE-1). The role of this continuity is contingent on the context but serves primarily as a stabiliser (SOURCE-1). In the freely hanging arm, the Deep Front Arm Line plays a notable role in orienting postion of The Hand (SOURCE-1). Conversely, in closed-chain movements such as the quadruped position this line stabilises lateral movement of the trunk (SOURCE-1). The Deep Front Arm Line is one of four Arm Lines that course the upper limb.
The following lists bony and muscular landmarks that are integrated into the Deep Front Arm Line from most proximal to distal (SOURCE-1):
Radial Periosteum
As scientific understanding of Fascia l structures is still in its infancy, the sophisticated and interrelated Fascial Lines discussed by Thomas Myers are yet to gain full support of the literature. With this said, there is growing evidence of myofascial continuities that reflect some of the relations described by Fascial Lines :
Clavipectoral Fascia - envelops the Pectoralis Minor and Subclavius (SOURCE-2). Laterally, the Clavipectoral Fascia anchors to the Coracoid Process of Scapula and its investing Fascia is continuous with the attaching Short Head of Biceps and Coracobrachialis (SOURCE-2)
Biceps Brachii to Radius - while a continuity between the anterior upper arm and forearm is well established, support for the Deep Front Arm Line at The Elbow is ambiguous (SOURCE-2+3+4+5+6). The Distal Biceps Brachii Tendon does indeed make strong adherence to the Radial Tuberosity of Radius (SOURCE-2). In theory and by account of Thomas Myers, this would insinuate fascial continuity is relayed along the Periosteum of Radius ; however, this is yet to be supported (SOURCE-1). Another possible avenue of continuty would be through the Bicipital Aponeurosis which arises from the Distal Biceps Brachii Tendon , with some authors attributing the Short Head of Biceps as the predominant source (SOURCE-3). This aponeurosis is described to be continuous with the proximalAntebrachial Fascia(deep Fascia of forearm) which distinguishes and encircles musculature related to the Radius and Intermuscular Septum of Forearm which courses between the forearm Bones (SOURCE-2+3+4+6). This continuity is supported by the fact that tension in the Bicipital Aponeurosis is relayed longitudinally along the length of the forearm (SOURCE-6)
Distal Radius to Thenar Muscles - in terms of support, there appear to be three distinct avenues by which the Fascia that relates to the Radius may course over The Wrist and onto the Thenar Muscles :
Radial Collateral Ligament of The Wrist - this continuity is most congruent with Thomas Myers’ original description (SOURCE-1). At the distal end of the Radius , the Radial Collateral Ligament of Wrist extends from the Styloid Process and inserts on the distolateral palmar surface of the Scaphoid and lateral surface of the Trapezium (SOURCE-2). Forming an aveunue for continuity, these Bones also serve as the attachment for the Thenar Muscles (SOURCE-2)
Radioscaphocapitate Ligament- this more extensive ligament shares neighbouring attachments between the Radial Styloid and the Scaphoid , thus anatomically functioning as a radial collateral ligament and forming continuity into The Wrist (SOURCE-2+9). Unlike the collateral ligament, the Radioscaphocapitate Ligament extensive relations with neighbouring ligamentous structures such as the Triangular Fibrocartilage which implicates it as a notable site of fascial continuity (SOURCE-9)
Antebrachial Fascia to Thenar Muscles - the Anterior Antebrachial Fascia is distally continuous with the Palmar Fascia which recieves reinforcement from the Palmaris Longus aponeurosis that becomes tendinous around the mid-forearm (SOURCE-2+8). This fascial sheath extends fibres to the Flexor Retinaculum (wrist) it courses superiorly of and the Fascia over the Thenar Muscles , forming continuity (SOURCE-8). Tension applied to a superior segment of this continuity has been shown to be relayed onto the Palmar and Thenar Fascia , supporting this relation (SOURCE-8)
The following observations may be indicative of Deep Front Arm Line dysfunction (SOURCE-1+3):
Resting Posture
Rounded Shoulders - excessive GH Joint - Internal Rotation and Scapulothoracic Joint - Protraction
Anterior Scapular Tilting
Excessive GH Joint - Adduction may suggest Coracobrachialis hypertonicity
Excessive Elbow - Flexion may suggest Brachialis hypertonicity
Excessive Elbow - Supination may suggest Supinator hypertonicity
Movement
Horizontal GH Joint - Extension - may be used to dermine the relative tone between the Deep Front Arm Line and Superficial Front Arm Line. This movement when performed in GH Joint - External Rotation emphasises the superficial line, while the addition of GH Joint - Internal Rotation emphasises the deep line (SOURCE-1). A disparity in range may indicate restriction with the regions of the greatest stretch sensation suggesting which tissues require the most attention (SOURCE-1)
greatest sensations of stretch as these landmarks are most likely restricted and require lengthening.
GH Joint - Flexion - restricted end-range
Symptoms of Pain may be greater with all involved joints locked rather than bent as the fascial line is pulled taut
Median Nerve Entrapment - from thickened Bicipital Aponeurosis
Determining the direction and extent of Fascia l restriction can be done with a light pressure over a desired segement and applying a superficial glide. The region and direction of greater soft-tissue resistance would suggest fascial restriction.
Treatment for Deep Front Arm Line dysfunction emphasises restoring Fascia l mobility and stability of the arm and trunk during open and closed-chain activities that involve The Hand . In some instances the release of a single structure contained within the Deep Front Arm Line forms an effective treatment, while in others the entire Fascia l line may require attention.
The following stretching techniques may be beneficial for dysfunction of the Deep Front Arm Line:
Door Frame Shoulder Stretch - self-guided anterior shoulder stretch with large Horizontal GH Joint - Abduction range
Split Stance Biceps Stretch ( Thumb down variation) - self-guided anterior shoulder stretch with large GH Joint - Extension range
Scapulothoracic Joint - Depression and Scapulothoracic Joint - Retraction with hands linked behind back
Banded Capsule Rolls - split stance biceps variation that emphasises shoulder rotation
Shoulder Dislocates - mobility exercise that emphasises the greatest circumduction range possible
Wheel Pose - full bridge variation that lengthens entire anterior chain
Dead Hangs - whole body traction for Pull and Push muscles with large overhead range
Jefferson Curl - with arms raised overhead into a stretch
Myofascial Release of the following structures through Massage or self-guided means may be of benefit to those with Deep Front Arm Line dysfunction, with specific techniques often discussed on their respective pages:
Practitioner-Guided
Pectoralis Minor - as the overlying Pectoralis Major may obstruct treatment, the Pectoralis Minor may be accessed from its lateral side, under the overlying Muscle (SOURCE-1). Patient lies supine with ipsilateral hand behind head (or similar positon as is comfortable). Fingers glide over the Ribs and under the Pectoralis Major muscle belly to apply pressure in the direction of the Sternoclavicular Joint . Fibres from the fifth to possibly the third Ribs may be palpable (SOURCE-1). From this position the fibres can be lifted from the Ribs , elongated with deep Breathing and/or complimented by active movement with arm elevation (SOURCE-1)
Biceps Brachii - in the case of chronic restriction, treatment to the Biceps Brachii may be applied as a superficial glide with broad contact in the direction of restriction (typically inferiorly) (SOURCE-1). At their polar ends, the two heads of Bicep form multiple crossovers with other Arm Lines , including the Deep Back Arm Line and Superficial Front Arm Line (SOURCE-1). Additionally the Biceps overlie several deeper Muscles such as the Coracobrachialis , Brachialis and Supinator . Often restriction in this area is more responsive to liberating the Biceps from any local adherence it has to these closely related structures (SOURCE-1). While specific techniques for the crossovers are found on their respective pages, the underlying muscles may be treated with several technqiues including, “pin and stretch”, deeper glides alonng the length of the muscle or transverse glides to lift distinguish the Fascia l layers
The following Strength techniques can be used for the Deep Front Arm Line:
Isometric Chest Squeezes - isometric exercise that isolates Chest
Banded Horizontal Adduction - low load isotonic horizontal adduction exercise
Bottoms-Up Kettlebell Walk - isometric push/ stability exercise with or without perturbation
Chest Press Machine - rudimentary horizontal push machine
Pallof Press - low load horizontal push exercise that emphasises anti-rotation of Core
Push-Up - bodyweight isotonic horizontal push exercise
Push-Up Plus - push-up variation with additional Scapulothoracic Joint - Protraction
Banded Russian Holds - isometric low resistance anti-rotation exercise
Chest Fly - large horizontal abduction range to emphasise lengthening of the Chest
Front Raises - isotonic GH Joint - Flexion exercise with many variations
Overhead Press - isotonic vertical push exercise with large overhead range
DB Shoulder Press - unilaterally loaded overhead press variation
Farmers Carry - upperbody/ Core isometric exercise with perturbation of walking
Suitcase Carry - unilateral farmers carry which emphasises crossbody functional patterns
Push Press - wholebody, explosive variation of the Overhead Press
Kneeling Landmine Press - wholebody, explosive vertical pressing exercise with large overhead range
Split Stance Landmine Press - crossbody, standing variation of the Kneeling Landmine Press
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