Automated fabrication of mobility aids (AFMA): Below-knee CASD/CAM testing and evaluation program results

Houston, Vern L.; Burgess, Ernest M.; Childress, Dudley S.; Lehneis, H R; Mason, Carl P.; Garbarini, Mary Anne; LaBlanc, Kenneth P.; Boone, David A.; Chan, Richmond B.; Harlan, John H.; Brncick, Michael D

doi:10.1682/jrrd.1992.10.0078

Cited by 25 publications

(5 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Further, if computer-socket manufacturing errors are inconsistent from one fabrication run to the next and the errors are substantial, a practitioner will have difficulty effectively optimizing the socket shape file. This problem might explain why there is a wide range in the number of sockets (1 to 5) reported necessary to achieve an acceptable fit in computer-socket design and manufacturing literature [3–6]. Particularly for young prosthetists, computer-socket manufacturing errors can add significant challenge to prosthetic design.…”

Section: Introductionmentioning

confidence: 99%

Computer-socket manufacturing error: How much before it is clinically apparent?

Sanders¹,

Severance²,

Allyn³

2012

JRRD

View full text Add to dashboard Cite

Abstract-The purpose of this research was to pursue quality standards for computer-manufacturing of prosthetic sockets for people with transtibial limb loss. Thirty-three duplicates of study participants' normally used sockets were fabricated using central fabrication facilities. Socket-manufacturing errors were compared with clinical assessments of socket fit. Of the 33 sockets tested, 23 were deemed clinically to need modification. All 13 sockets with mean radial error (MRE) greater than 0.25 mm were clinically unacceptable, and 11 of those were deemed in need of sizing reduction. Of the remaining 20 sockets, 5 sockets with interquartile range (IQR) greater than 0.40 mm were deemed globally or regionally oversized and in need of modification. Of the remaining 15 sockets, 5 sockets with closed contours of elevated surface normal angle error (SNAE) were deemed clinically to need shape modification at those closed contour locations. The remaining 10 sockets were deemed clinically acceptable and not in need modification. MRE, IQR, and SNAE may serve as effective metrics to characterize quality of computer-manufactured prosthetic sockets, helping facilitate the development of quality standards for the socket manufacturing industry.

show abstract

Section: Introductionmentioning

confidence: 99%

Computer-socket manufacturing error: How much before it is clinically apparent?

Sanders¹,

Severance²,

Allyn³

2012

JRRD

View full text Add to dashboard Cite

show abstract

“…One problem with the comparison of amputee anthropometrics is the wide range of available calipers, rulers, and tape measures [6]. In addition, a variety of tools for shape capture have been developed, including generally accepted computer-aided design/computer-aided manufacturing digitizers [7][8][9] along with custom-designed methods using X ray and cineradiography [10], finite element modeling [11], laser and optical capture methods [12][13], ultrasound [14], and spiral x-ray computed tomography [6,[15][16]. Anecdotal observation suggests that even traditional hand-measurement devices vary in terms of precision, accuracy, and ease of use.…”

Section: Introductionmentioning

confidence: 99%

Consistency and accuracy of measurement of lower-limb amputee anthropometrics

Geil¹

2005

JRRD

View full text Add to dashboard Cite

Lower-limb amputees often exhibit large fluctuation in residual-limb shape, necessitating careful observation and anthropometric measurement for prosthetists to ensure socket fit. Anthropometric measurement may become more important as an outcome measure indicating success in rehabilitation. This study investigated the accuracy and reliability of seven prosthetic anthropometric measurement devices as used by a group of eight prosthetic-orthotic practitioners and a group of five prostheticorthotic students to measure six common anthropometric dimensions on three foam positive models of transtibial amputee residual limbs. Two of the models were identical, enabling assessment of individual repeatability. Some clinically significant errors were noted in the results; however, the general variability in measurements was not clinically significant. Students were slightly more consistent than practitioners; students were more consistent with linear measurements, while practitioners were more consistent with circumferential measures. The results further demonstrated that the VAPC measurement device used in the study was both inaccurate and unreliable.

show abstract

“…Testing sites on lower limbs and forearms were usually selected in those investigations. Computer-aided design and computer-aided manufacturing (CAD/CAM) techniques and finite element (FE) analysis have been introduced into the design of prosthetic sockets and cushions [2], [4], [10], [15], [23]. Determination of quantitative biomechanical properties in residual limb tissues in compression has become important so as to provide inputs to these advance design tools.…”

mentioning

confidence: 99%

Effective elastic properties for lower limb soft tissues from manual indentation experiment

Zheng

Mak

1999

IEEE Trans. Rehab. Eng.

102

View full text Add to dashboard Cite

Abstract-Quantitative assessment of the biomechanical properties of limb soft tissues has become more important during the last decade because of the introduction of computer-aided design and computer-aided manufacturing (CAD/CAM) and finite element analysis to the prosthetic socket design. Because of the lack of a clinically easy-to-use apparatus, the site and posture dependences of the material properties of lower limb soft tissues have not been fully reported in the literature. In this study, an ultrasound indentation system with a pen-size handheld probe developed earlier by the authors was used to obtain the indentation responses of lower limb soft tissues. Indentation tests were conducted on normal young subjects with four females and four males at four sites with three body postures. A linear elastic indentation solution was used to extract the effective Young's modulus from the indentation responses. The determined modulus ranged from 10.4 to 89.2 kPa for the soft tissues tested. These results were in a similar range as those reported in the literature. The thickness of the lower limb soft tissues varied slightly with body posture changes. The Young's modulus determined was demonstrated to be significantly dependent on site, posture, subject and gender. The overall mean modulus of male subjects was 40% larger than that of female subjects. No significant correlation was established between the effective Young's modulus and the thickness of entire soft tissue layers.

show abstract

Automated fabrication of mobility aids (AFMA): Below-knee CASD/CAM testing and evaluation program results

Cited by 25 publications

References 3 publications

Computer-socket manufacturing error: How much before it is clinically apparent?

Computer-socket manufacturing error: How much before it is clinically apparent?

Consistency and accuracy of measurement of lower-limb amputee anthropometrics

Effective elastic properties for lower limb soft tissues from manual indentation experiment

Contact Info

Product

Resources

About