The biomechanical basis of spinal manual therapy

Rights statement
Awarding institution
  • University of Strathclyde
Date of award
  • 1995
Thesis identifier
  • T8614
Qualification Level
Qualification Name
Department, School or Faculty
  • Mobilisation and traction are commonly employed manual therapy techniques in the management of low back pain. The present work examined the biomechanical effects produced by these procedures. Lateral radiographs were taken of normal living subjects who were subjected to posteroanterior mobilisation loads. The motion segments were found to extend, except the L5/S1 segment which showed a less consistent pattern. The upper segments also translated posteriorly and the lower ones anteriorly. In a separate cadaveric motion segment study, the movements produced by mobilisation loads were examined after sequential dissection of the anatomical structures. The disc was found to be the principal structure that resisted the loads. The intervertebral movements produced by posteroanterior mobilisation are small in magnitude. It is unlikely that the therapists can palpate the movements reliably. The results suggest that the technique is a passive test of the spine in threepoint bending. Posteroanterior stiffness is likely to be affected by disc lesions and scarring of soft tissues. The movements produced by traction were examined in cadaveric lumbosacral spines. An attempt was made to reproduce the in vivo loading conditions as accurately as possible. The motion segments were found to flex and translate anteriorly. These were accompanied by increases in the foraminal sizes. Most of these mechanical changes occurred after the application of flexion moment which simulated the Fowler's position: The time-dependent effects of traction were then studied by subjecting the specimens to repeated cycles of traction loads. It was revealed that most of the mechanical effects of traction were lost within 15 minutes after treatment. The results suggest that traction may enlarge a pathologically narrowed foramen and reduce a posterior disc bulge and. [sic] It may also have the potential effect of stimulating the mechanoreceptors of the posterior elements, producing a relief of pain. These therapeutic effects may persist after treatment, although the spine recovers mechanically within a short period of time. The experimental results have added distinctly to the body of knowledge on the scientific basis of manual therapy, but it is felt that farther research in this area is still necessary.
Resource Type
Date Created
  • 1995
Former identifier
  • 495783