Changes in the Ulnar Tissues by Shear-wave Elastography
Condition: Elastography; Soft Tissue; Muscle Tonus
Study type: Observational

Summary: 
      A single-center, observational, prospective, single cohort study with before-after design.
      Evaluation by shear-wave elastography, measured in kilopascals (KPa), of the muscle, tendon
      and cubital nerve, before and after the maneuver of putting in tension of the ulnar nerve.
    

Detailed description: 
      Once each subject has signed the informed consent document and it has been verified that the
      inclusion criteria are met, it will be assigned the same identification number (ID) that is
      related to its Clinical History (CH) by simple coding; custody of the file with the
      relationship of each ID with its CH will be the responsibility of the principal investigator.

      Body placement: The participants will be placed in the supine position with the hips and
      knees bent, in such a way that the soles of the feet rest on the plane of the stretcher. the
      palm of the hand of the left extremity will rest on the abdomen and the head in a neutral
      position, with the maximum relaxation of the sternocleidomastoids.

      Upper limb placement: The right extremity will be placed in abduction of 90°, the elbow to
      flexion of 10° and the forearm to 30° of supination. Wrist and joints metacarpophalangic
      (mcf), proximal interphalangeal (ifp) and distal interphalangeal (ifp) of the first three
      fingers in full extension. The articulations mcf, ifp, ifd of the fourth and fifth fingers in
      a relaxed position. In this position, the first ultrasound measurement will be taken.

      Tension maneuver of the ulnar nerve: An expert researcher in mobilization of neural tissue
      will perform an extension of fourth and fifth finger, respecting the initial parameters that
      are maintained in position by the splint. To do this, he will use the index and middle of his
      left hand and make a contact on the palmar side of the fingers and a back pressure with the
      thumb on the back of the hand. Next, it will extend the fingers until the exponential
      resistance following the path of elastic deformation (linear resistance) of the tensioned
      tissues is perceived. At this time the new ultrasound record will be made.

      Ultrasound records: A Toshiba ai800 ultrasound scanner (Toshiba Medical Corporation, Japan)
      with a multifrequency linear probe plt-1005bt 14l5 (5-14 Mhz) will be used. The
      identification number (ID) registered in the ultrasound will correspond to the participant
      number.

      The same researcher, with experience in the acquisition and management of medical images,
      will perform the ultrasound and in-line measurements of the images obtained.

      The ultrasound will be obtained in a pre and post-median situation after the neural tension
      put on by the expert investigator in manual therapy and a label will be consigned in the
      images indicating if the acquisition was "pre" or "post".

      To perform the acquisition of the images the probe wil be positioned on the skin of the
      forearm with minimal pressure and with angulation such that there is no anisotropy. The
      anatomical region where the myotendinous junction of the flexor carpi ulnaris muscle and the
      ulnar nerve is observed will be searched transversally. the parameters of emission power,
      general gain, depth of the image, position of the focus and frequency of emission will be
      adapted to obtain a quality image. The protocol will be the following:

        -  2d image in transverse plane.

        -  2d image in longitudinal plane.

        -  Shear-wave elastography in longitudinal plane.

        -  Measurement of the images: They will be carried out off-line using the elastography
           software of the team itself once all the participants have been explored. three regions
           of interest (ROIs) adjacent to each other will be established in the body of the ulnar
           nerve, three in the distal area of the flexor carpi ulnaris muscle and three in the
           tendinous body of the same muscle. The size of the ROI should include the entire body of
           the mentioned structures.

        -  The average value of the three ROIs will be written down in units of pressure (KPa).
    

Intervention name(s): shear-wave elastography
Intervention type(s): Diagnostic Test
Intervention description(s): Measurement by shear-wave elastography of the nerve, muscle and ulnar tendon before and after the tension of the ulnar nerve
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Healthy volunteers recruited among the students of the Francisco de Vitoria University.
      
Keywords: Elastography, Nervous tissue, Muscle tonus