Link to Figures Show Figures
	Article Text Figures References
	Send Link Send HTML Article

Technical Note: Technique for Setting Up Static Alignment and Permanent Attachment of the Syme's Type Foot

Steven R. Childs
Charles W. Childs, C.P.O.

Introduction

The only Syme's feet available for many years were the external wood keel type or a custom foot manufactured from a pattern. For the prosthetist to attach the Syme's foot involved bonding the foot in place, checking the alignment, detaching and rebonding the foot if there were changes, and then laminating the foot to the socket for final attachment. This was a time consuming technique and made for a very heavy finished prosthesis.

With the advent of the internal keel foot came an easier and improved method of attachment by means of an adapter nut and bolt. This eliminated the need to laminate the foot to the socket.

Static alignment of the prosthesis was usually accomplished either by educated guesswork or knowledge gained from experience.

The technique described takes the guesswork out of performing static alignment of the Syme's prosthesis. It is easy and it works with all types of Syme's feet currently on the market.

Procedure

First locate the mid-point on the anterior aspect of the socket at the patellar tendon level and make a mark 1-inch medial to this point (Figure 1) . Then locate the mid-point on the proximal medial aspect of the socket and make a mark 1-inch posterior to this point (Figure 2) . Repeat this laterally.

Locate and mark the mid-point on the distal anterior, medial and lateral aspects of the socket. Connect the patellar tendon level marks with the distal marks. Extend these lines around the distal end (Figure 3) .

Drill a 3/4-inch hole where these lines intersect. It is sometimes necessary to move the center of this hole approximately 1/4inch lateral for very long sockets to obtain the necessary lateral support.

Place the Syme's adapter nut from the inside of the socket into the hole. Bolt the Syme's foot to the socket using a 3-inch foot bolt and set in static alignment following the alignment marks previously drawn. Securely tape the foot and socket together, calculate how long the foot bolt needs to be and re move the bolt. The tape will hold the foot and socket together while the foot bolt is cut to the proper length and make it easier to reinstall the foot bolt.

The prosthesis is now ready to fit. Alignment changes are made by loosening the foot bolt and sliding or rotating the socket to the desired position.

After dynamic alignment is completed, pour polyester, acrylic resin or dental acrylic around the top of the adapter nut to lock it in place. Mark the placement of the foot on the socket and then remove the foot. Rough up the area of socket where it attaches to the foot. Re-attach the foot loosely using a longer bolt. Mix dental acrylic so that it is runny, add a drop or two of pigment, stir thoroughly and pour between socket and foot. Immediately tighten the foot in proper alignment and let cure. Replace the long bolt with the proper length bolt. Blend foot to the socket and the prosthesis is ready for delivery.

Conclusion

Using this technique can cut down on the fabrication time and guesswork involved in setting the prosthesis up for dynamic alignment. It works well with any type of Syme's foot currently available, and it also works with any style of socket, i.e., medial opening, posterior opening, etc.

Acknowledgements

This technique was first shown to me when I started work in this business by my father, Chuck Childs, C.P.O. Over the years this technique has been shared with other prosthetists with success. This technique is written down for them and for my father.

Steven R. Childs is president of Pacific Orthotic Prosthetic Service Inc., 111 E. First St., Phoenix, Ore. 97535.

Charles W. Childs, C.P.O., was owner and operator of Pacific Orthotic Prosthetic Service Inc. until his death in 1985.

References:

1. Foort J. The Canadian-type syme prosthesis. Lower-extremity Amputee Research Project, Institute of Engineering Research, University of California at Berkeley, Series 11, Issue 30, December 1956.
2. Hanger HB. The Syme and Chopart prosthesis, a manual for prosthetists. Prosthetic-Orthotic Education, Northwestern, University Medical School.
3. Quigley MJ, CPO, Hamontree, SE, CP, Antorietto J, The Rancho Syme prosthesis with the Regnell foot, Clinical Prosthetics and Orthotics, 1987; (12)1:33-40.