Investigation of soft-tissue stiffness alteration in denervated human tissue using an ultrasound indentation system.
OBJECTIVE
Differences in soft-tissue stiffness may provide for a quantitative assessment and detection technique for pressure ulcers or deep-tissue injury. An ultrasound indentation system may provide a relatively convenient, simple, and noninvasive method for quantitative measurement of changes in soft-tissue stiffness in vivo.


METHODS
The Tissue Ultrasound Palpation System (TUPS) was used to quantitatively measure changes in soft-tissue stiffness at different anatomical locations within and between able-bodied persons and individuals with chronic spinal cord injury (SCI). The stiffness of soft tissue was measured at the ischial tuberosity, greater trochanter, posterior midthigh, and biceps brachii. Additionally, soft-tissue thickness and soft-tissue deformation were also measured.


RESULTS
Significant differences in soft-tissue stiffness were observed within the various anatomical locations tested, in both the able-bodied and SCI groups. Differences in soft-tissue stiffness were also observed between the 2 groups. Participants with SCI had significantly softer tissue in their buttock-thigh area.


CONCLUSIONS
TUPS is a clinically feasible technology that can reliably and effectively detect changes in soft-tissue stiffness. The study has provided a better understanding of the tissue mechanical response to external loading, specifically in the SCI population, suggesting the use of tissue stiffness as a parameter to detect and assess pressure-related soft-tissue injury.
Makhsous
Mohsen
M
Department of Physical Therapy and Human Movement Sciences , Northwestern University, Chicago, Illinois 60640, USA. m-makhsous2@northwestern.edu
Venkatasubramanian
Ganapriya
G
Chawla
Aditya
A
Pathak
Yagna
Y
Priebe
Michael
M
Rymer
William Z
WZ
Lin
Fang
F
D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009121:Muscle Denervation; D009716:Numerical Analysis, Computer-Assisted; D017695:Soft Tissue Injuries / Q000000981:diagnostic imaging* / Q000209:etiology* / Q000473:pathology; D013119:Spinal Cord Injuries / Q000150:complications*; D014465:Ultrasonics; D014463:Ultrasonography