TI 2 Mod 2 Topic 2 Trunk Stability and Coordination

Core stability

The ability to stabilize the trunk while the arms and legs move during functional movements; creates 360 degrees of stiffness around the spine; spares spine from excessive load; transfers force from lower body to upper body and vice versa

Core muscles included

Muscles that stabilize the hips; muscles that make up the torso (front sides and back); muscles that stabilize the shoulders

Abdominal canister (core box)

Front and sides = abdominal muscles; back = paraspinal and gluteal muscles; roof = diaphragm; floor = pelvic floor and hip girdle muscles; abdominal muscles create a rigid cylinder around the spine

Inner core muscles (local/segmental)

Transversus abdominis; multifidus; pelvic floor; internal abdominal obliques (deep fibers); diaphragm; sometimes deep fibers of psoas and deep hip rotators

Function of transversus abdominis

Activity recorded during entire range of flexion and extension; co-activation with other abdominals needed to maintain spinal stability

Function of multifidus

Deeper muscle with direct attachments to spinal segments; stabilizes motion segment during lifting and rotational movements; unisegmental fibers act as force transducers; high concentration of muscle spindles

Pelvic floor function

Co-contracts with abdominals to increase intra-abdominal pressure during spinal movement

Outer core muscles (global/superficial movers)

Rectus abdominis; external obliques; erector spinae; quadratus lumborum; hip muscle groups

External obliques limitation

Involved in rotational movements but do not have direct attachment to spinal segments; unable to stabilize individual segments

Erector spinae limitation

Involved in lifting but no direct segmental attachment; cannot stabilize individual segments

Change in motor patterns due to pain

Neural subsystem normally activates transverse abdominis and multifidus ahead of loading; with pain there is a delay in multifidus contraction; larger global muscles (erector spinae) compensate; leads to excessive stress on low back; creates vicious cycle of pain and disability

Four steps of core stability training

Step 1 = motor learning (drawing-in maneuver transverse abdominis activation); Step 2 = maintain motor control while adding simple patterns (extremity movements); Step 3 = more complex exercises and patterns; Step 4 = automatic response (unplanned or unpredictable situations)

Guidelines for implementing stability program

Promote kinesthetic awareness of transverse abdominis and multifidus activation; add extremity movements and different patient positions; emphasize muscular endurance (maintain contraction for longer periods); promote alternating isometrics or rhythmic stabilization; incorporate balance training

Lower abdominal bracing supine

Develop neutral pelvis; perform gentle contraction of transverse abdominis without holding breath or moving pelvis

Lower abdominal retraining supine with leg lifts

Abdominal bracing while lifting one leg then the other; maintain neutral spine

Bridging exercise

Tighten buttocks; keep pelvis level; do not let it sag; lift pelvis off table; progress to unilateral bridging

Quadruped progression step 1

Develop neutral pelvis in quadruped position

Quadruped progression step 2

Quadruped arm lifts with bracing; use cane or bar on patient's back as feedback tool

Quadruped progression step 3

Quadruped leg lifts with bracing

Quadruped progression step 4

Alternating leg and arm lifts with bracing (bird-dog)

Side lying stabilization step 1

Side support with knees flexed

Side lying stabilization step 2

Side support with knees flexed and bracing

Side lying stabilization step 3

Side support with knees extended

Side lying stabilization step 4

Side support with knees extended and bracing

Local/deep muscle assessment tests

Abdominal drawing-in maneuver (transversus abdominis); isometric activation of multifidus; normal breathing (diaphragm); pelvic floor activation

Global/superficial muscle outcome measures

Prone instability test; prone extension endurance test (Biering-Sorensen); side bridge endurance test (quadratus lumborum); pelvic bridging; leg lowering test (lower abdominal strength); curl-up test; hip external rotation strength; modified Trendelenburg test (single leg squat frontal plane); single leg squat in sagittal plane; single leg squat in transverse plane

Clinical prediction rules for specific motor control response (low back)

Younger age (

Treatment approach for local/deep muscles

Retrain specific motor control before moving into more global training

Treatment approach for global/superficial muscles

Perform exercises with correct lumbopelvic posture and control of local/deep muscles; duration of hold and repetitions can be varied as long as good control is maintained

Summary statement for core stability

No single muscle or single exercise for low back problems; follow evidence-based approach progressing from specific motor control to global and functional exercises