The Back Functional Line is one of several Fascial Lines proposed by Thomas Myers (SOURCE-2). This line serves as a prominent posterior link between The Shoulder Girdle and The Hip of the opposing side. Given this course and Muscles it coordinates, the Back Functional Line plays an integral role in maintaining dynamic stability of the Pelvis and diagonal force transfer. This line is the Fascia l line equivalence of the Posterior Sling.
The following lists bony and muscular landmarks that are integrated into the Back Functional Line from most proximal to distal (SOURCE-2):
Muscle / Tendon
Lumbodorsal Fascia
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 . The crux of this line is the cross-body course between the Latissimus Dorsi and contralateral Gluteus Maximus , a continuity which is well supported (SOURCE-1+5). The specifics of this continuity are detailed below:
Latissimus Dorsi to Thoracolumbar Fascia - the Latissimus Dorsi has an extensive direct attachment to the Thoracolumbar Fascia (SOURCE-6+7)
Thoracolumbar Fascia to Sacrotuberous Ligament - the Gluteus Maximus serves as a site of convergence between the Thoracolumbar Fascia and the Sacrotuberous Ligament (SOURCE-3+6). The Gluteus Maximus has soft-tissue origins from the Sacrotuberous Ligament and Lumbar Fascia (SOURCE-8). The thick aponeurosis of Thoracolumbar Fascia courses in a caudolateral (diagonal) direction to blend with fibres of the contralateral (opposing) Gluteus Maximus (SOURCE-9)
Sacrotuberous Ligament to Fascia Lata and consequently Gluteus Maximus - the inferior border of the Sacrotuberous Ligament blends with the Fascia Lata that is superiorly and posteriorly attached to the Sacrum and Coccyx (SOURCE-6). The wide, deep Fascia of the thigh, Fascia Lata , envelops the muscles contained within this region, including the Gluteus Maximus and Tensor Fasciae Latae (SOURCE-6)
Gluteus Maximus to Vastus Lateralis - this continuity was identified in the marjority of studies (SOURCE-1). The distal Tendons of the Gluteus Maximus and Tensor Fasciae Latae converge at the lateral thigh to descend as a lateral thickening of Fascia , known as the Iliotibial Band (SOURCE-6). The bands attachment on the anterolateral aspect of the Lateral Condyle of Tibia (Gerdy’s Tubercle) leaves it superficial of the Vastus Lateralis where it blends with an aponeurotic expansion the Muscle extends (SOURCE-6)
The following signs may be observable with Back Functional Line dysfunction:
Trunk Rotation
Asymmetrical Ribs
Lower Extremity
Trendelenburg’s Sign - severe Gluteus Maximus deficit could cause hip drop
Gait - asymetrical arm swing, stride length and Pelvis rotation
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 Back Functional Line dysfunction emphasises restoring Fascia l mobility, Core / Pelvis stability and diagonal force transfer. In some instances the release of a single structure contained within the Back Functional 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 Back Functional Line:
Seated Thoracic Rotation with Breathing - large lateral flexion and rotation range coupled with breathing
Bent Over Lat Stretch - accessible active stretch with large GH Joint - Flexion or Horizontal GH Joint - Adduction range
Bretzel 1.0 - wholebody technical stretch that incorporates anterior shoulder
Bretzel 2.0 - variation with greater hip extension range
Swimmers Oblique Extensions - exercise that may be used to lengthen entire Lateral Line through large body-wide lateral-flexion range
Myofascial Release of the following structures through Massage or self-guided means may be of benefit to those with Back Functional Line dysfunction, with specific techniques often discussed on their respective pages:
Practitioner-Guided
Latissimus Dorsi - with patient prone or supine, a superficial glide to the Muscle is applied along its length over the posterolateral Ribs in the direction of Fascia l restriction, typically from the Axilla (armpit) towards the Thoracolumbar Fascia . The patient may move through GH Joint - Abduction and GH Joint - Adduction to elongate the Muscle under the gliding pressure
Thoracolumbar Fascia - with patient prone, a superficial glide may be applied in a contralateral direction from the posterior Ribs to the oppsing hip. Particular attention may be given to the attachments onPosterior Superior Iliac Spineand Sacral Base
Gluteus Maximus - treatment more closely reflects a deep tissue release and may be performed with The Elbow . Points of particular relevance may be its attachments to the Iliac Crest, Sacrum , Posterior Femur Head or the Sacrotuberous Ligament / Thoracolumbar Fascia it is continuous with
Vastus Lateralis - a superficial glide may be applied along the length of the anterolateral thigh in the direction of restriction, typically using the blade of the forearm or knuckles
The following Strength techniques can be used for the Back Functional Line:
Pallof Press - low load horizontal push exercise that emphasises anti-rotation of Core
Psoas Sit-Ups - core exercise the emphasises length of the Iliopsoas
Bird-Dog - bodyweight isotonic exercise that emphasises Posterior Sling / Core
Bird-Dog Row - One Arm Row variation that emphasises Posterior Sling
DB Snatch to Step-Up - wholebody DB Snatch variation that emphasises diagonal functional patterns
Farmers Carry - upperbody/ Core isometric exercise with perturbation of walking
Split Stance Landmine Press - crossbody, standing variation of the Kneeling Landmine Press
Single Leg Transverse KB Swings - isotonic rotations with significant emphasis on Balance
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