Here you can read about methods developed by the research group.


BioDex Multi-Joint System-4

BioDex (BioDex Corp., Shirley NY) is a dynamometer originally designed for training and rehabilitation of different muscle groups among athletes. The research group Clister has developed this device further into a validated method for testing and evaluating abdominal muscle strength and abdominal wall function in connection with abdominal rectus diastasis and giant ventral hernia.

The measurement is performed with the patient sitting in the BioDex, fixed by Velcro straps by the shoulders, crossed over the chest, and Velcro straps by the pelvis, hips and calves. The seat is adjusted to gain optimal positioning for measurement. All adjustable parameters are saved for later use, to rule out variations during recurring tests. These examinations are now performed by a physiotherapist certified for using BioDex.

Photo of the BioDex dynamometer

When the patient is positioned in the BioDex, a passive isokinetic test is performed for both concentric and eccentric movement. Two different speeds are used – 30 degrees/second and 60 degrees/second. An isometric test is also performed. All tests are performed five times. The unit used for measurement is newton meters.

Articles about the studies involving BioDex:

Operative correction of abdominal rectus diastasis (ARD) reduces pain and improves abdominal wall muscle strength: A randomized, prospective trial comparing retromuscular mesh repair to double-row, self-retaining sutures.

Emanuelsson P, Gunnarsson U, Dahlstrand U, Strigård K, Stark B.

Surgery. 2016 Nov;160(5):1367-1375.

Predictive Factors in the Outcome of Surgical Repair of Abdominal Rectus Diastasis.

Strigård K, Clay L, Stark B, Gunnarsson U.

Plast Reconstr Surg Glob Open. 2016 May 5;4(5):

Giant ventral hernia-relationship between abdominal wall muscle strength and hernia area.

Strigård K, Clay L, Stark B, Gunnarsson U, Falk P.

BMC Surg. 2016 Aug 2;16(1):50.

Correlation between abdominal rectus diastasis width and abdominal muscle strength.

Gunnarsson U, Stark B, Dahlstrand U, Strigård K.

Dig Surg. 2015;32(2):112-6.

Validation of BioDex system 4 for measuring the strength of muscles in patients with rectus diastasis.

Stark B, Emanuelsson P, Gunnarsson U, Strigård K.

J Plast Surg Hand Surg. 2012 Apr;46(2):102-5.

Assessment of abdominal muscle function using the BioDex System 4. Validity and reliability in healthy volunteers and patients with giant ventral hernia.

Gunnarsson U, Johansson M, Strigård K.

Hernia. 2011 Aug;15(4):417-21.

Different techniques for mesh application give the same abdominal muscle strength.

Johansson M, Gunnarsson U, Strigård K.

Hernia. 2011 Feb;15(1):65-8.

Intrastomal 3D ultrasonography

Parastomal hernia is common in patients with a permanent stoma. The distinction between parastomal hernia and a bulge is often vague. CLISTER has developed a method where three-dimensional intrastomal ultrasonography differentiates these conditions, while also making it possible to discover possible fistulas or abscesses.

An ultrasound machine with a 17 millimetre transducer is set to a frequency of nine megahertz and rectal scanning mode. The transducer is covered with a water-filled balloon, most commonly 30-40 millilitre, and taped individually according to the patients’ problems and conditions. These settings give the sharpest images, where you most easily can identify fascia, bowel and rectus muscle, as well as implanted mesh when present. It is also possible to evaluate whether the fascia is intact or not.

Photo of the ultrasound machine

Before the examination, local anaesthetic gel is applied to the stoma. The probe is inserted into the stoma orifice, and then further through the rectus muscle into the abdomen. The examination is performed in both supine and upright position.

Performing the examination is fairly easy and the learning curve is short. The examination is not painful and takes about 15-20 minutes.

Articles about the studies involving intrastomal 3D ultrasonography:

A comparison between intrastomal 3D ultrasonography, CT scanning and findings at surgery in patients with stomal complaints.

Näsvall P, Wikner F, Gunnarsson U, Rutegård J, Strigård K.

Int J Colorectal Dis. 2014 Oct;29(10):1263-6.

Intrastomal 3D ultrasound; an inter- and intra-observer evaluation.

Strigård K, Gurmu A, Näsvall P, Påhlman P, Gunnarsson U.

Int J Colorectal Dis. 2013 Jan;28(1):43-7.

3D intrastomal ultrasonography, an instrument for detecting stoma-related fistula.

Gunnarsson U, Strigård K.

Tech Coloproctol. 2012 Jun;16(3):233-6.

Imaging of parastomal hernia using three-dimensional intrastomal ultrasonography.

Gurmu A, Gunnarsson U, Strigård K.

Br J Surg. 2011 Jul;98(7):1026-9.