Aligning anatomical structure from spiral X-ray computed tomography with plantar pressure data.
OBJECTIVE
To determine the reliability of identifying the location of each metatarsal head from spiral X-ray computed tomography on a matrix type pressure sensor recording.


METHODS
Experimental; test-retest and within subject two-condition comparison.


BACKGROUND
Plantar pressure data quantify the amount of pressure and the general location of pressure. Specific anatomical structures associated with the site of pressure can only be determined by registering radiological data to the pressure sensor.


METHODS
Eighteen subjects, nine individuals without diabetes mellitus and nine individuals with diabetes mellitus, peripheral neuropathy, and a history of plantar foot ulcers, participated in plantar pressure testing and spiral X-ray computed tomography scanning of their foot. A registration technique was developed to align spiral X-ray computed tomography data with pressure sensor data.


RESULTS
When mapping the metatarsal head locations to the pressure sensor 48 of 90 metatarsal head locations were identical between repeated test occasions (53.3%), 40 of 90 metatarsal head locations were one pixel (5.08 mm) different between repeated test occasions (44.4%), and 2 of 90 were two pixels different (2.2%). Ninety-eight percent of repeated measures replicated exactly or varied by one pixel.


CONCLUSIONS
Anatomical data from spiral X-ray computed tomography scanning can be reliably co-registered with pressure data.


CONCLUSIONS
The ability to match bony anatomy to pressure data allows better understanding of structural factors contributing to peak pressure, provides precise information for three-dimensional modeling of the foot, and can improve orthotic fabrication and modification aimed at reducing pressure on the bottom of the foot.
Hastings
Mary K
MK
Washington University School of Medicine Program in Physical Therapy and Mallinckrodt Institute of Radiology, Room 1101, P.O. Box 8502, 4444 Forest Park Blvd., St. Louis, MO 63108-2212, USA. hastingsm@msnotes.wustl.edu
Commean
Paul K
PK
Smith
Kirk E
KE
Pilgram
Thomas K
TK
Mueller
Michael J
MJ
D048909:Diabetes Complications; D003920:Diabetes Mellitus / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000503:physiopathology; D003936:Diagnosis, Computer-Assisted / Q000379:methods; D005260:Female; D005528:Foot / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D005684:Gait; D006801:Humans; D008297:Male; D008682:Metatarsal Bones / Q000000981:diagnostic imaging / Q000503:physiopathology; D008875:Middle Aged; D010523:Peripheral Nervous System Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology*; D010808:Physical Examination / Q000379:methods; D011312:Pressure; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D013382:Subtraction Technique; D014057:Tomography, X-Ray Computed / Q000379:methods*