The Art of the Chiropractic Adjustment, Part VII
SOURCE: Dynamic Chiropractic
By Richard C. Schafer, DC, FICC
This series has strived to define certain general principles that underlie almost all chiropractic adjustive technics. Parts I and II reviewed depth of drive, the articular snap, segmental distraction, timing, the advantages of placing the patient’s spine in an oval posture, correct table height, and patient positioning objectives.
Part III summarized the factor of time in the clinical approach and its underlying biomechanical principles of tissue viscoelasticity, fatigue, creep, and relaxation. Part IV and V reviewed the need to visualize the loading effects on articular cartilage, joint lubrication, action of the intra-articular synovial tabs, the articular planes, the fundamental types of contact, contact points and their options, securing the contact hand, and the direction of drive. Part VI offered a rationale on adjustive velocity, and this concluding column on this subject describes various types of adjustive thrusts.
Types of Adjustive Thrusts
Test thrusts are mild preliminary thrusts applied before an actual corrective thrust is delivered. They have a twofold purpose: first, to acquaint the adjuster with the structural resistance present and patient response to the pressure applied; second, to acquaint the patient with what to expect. Surprise lowers a patient’s pain threshold.
The term leverage move refers to the use of counter pressure or contralateral stabilization. It is applied to prevent the loss of applied force, secure the most work with the least amount of energy expenditure, and concentrate the movement or force at the directed point of contact. Visualize! Only enough counter pressure is used to balance the force of the adjustive thrust. Leverage thrusts are the most commonly applied technic used in chiropractic.
An impulse thrust is the application of a short, sharp force without recoil. The hands adopt a preset tension in the line of drive, and the impulse is characterized by a high-velocity low-depth thrust.