Author: Desmidt Magali
Supervisor: Cremers Reiner
Background: Shortening of the iliopsoas muscle often causes lower back pain. In osteopathic practise, HVLA (high-velocity, low-amplitude) spinal manipulation can be used to correct somatic dysfunctions. Due to a short stretch of extrafusal fibres by performing a manipulation, the Golgi tendon is stimulated and therefore results in muscle relaxation. Various investigations proved the effect on paraspinal tissue. However, the neurophysiological reaction to the peripheral muscles is not yet clearly understood.
Objective: This investigation was designed to assess the clinical relevance and added value of an HVLA manipulation on the thoracolumbar spine for the treatment of iliopsoas shortening.
Materials and methods: The study is a single blind randomised controlled trial where 44 subjects with iliopsoas shortening and a somatic dysfunction between Th14 – L4 were included. The combination of an HVLA manipulation and MET (muscle energy technique) on the iliopsoas muscle, or exclusively MET was performed. Subjects with an additional rectus femoris shortening, which could confound the MTT (modified Thomas test), were equally divided over the experimental and control groups. By using digital photography, hip-extension values were measured before and after treatment, with the subject performing the MTT.
Results: Significant effects (p=0.007) were found for the experimental group that scored mean differences in hip-extension angles between pre- and post-testing’s that were 5.2 degrees larger than the control group. A significant difference was found for the examiner (p=0.038) as well, in a model with only the main effects – but the interaction between ‘condition’ and ‘examiner’ showed no significant difference.
Conclusion: The outcomes aligned with the presumption that an HVLA manipulation on the thoracolumbar region does add value to the treatment of iliopsoas shortening. However, there was a possibility that these outcomes were due to the origin of the muscle at the thoracolumbar spine, instead of due to a neurophysiological response.