Amputation of the Hand or Finger and Prosthetics
A constraint confronting the choice of fitting a long fingerresiduum with a thimble prosthesis lies in the short residual length--distal to the PIPJ--that is available for a suction-type fit and theassociated higher probability of an accidental slipping off of prosthesisfrom a suction loss. The problem is compounded by the fact that asuction-fitted prosthesis acts very much like a pressure garment and whenworn for a protracted period, can shrink the residuum via soft tissuecompression. The challenge in fitting thimble prostheses is to achieve agood prosthetic fit despite these constraints. In these suction-fittedprostheses, the elastic and nonporous silicone rubber allows an airtight"cupping" of the residuum such that an incipient slippage of the prosthesisis immediately followed by an internal vacuum effect that checks furtherdisplacement. To ensure a secure prosthetic fit, the proximal segment ofthe prosthesis is made circumferentially smaller than the segment of theresiduum over which it "cups". This is done primarily through priorcircumference modification of the finger models after which the prosthesisis modeled.
LEOW and PHO: Thimble prostheses for distal finger …
Abstract — The prosthetic fit of a thimble-type esthetic siliconeprosthesis was retrospectively reviewed in 29 patients who were fittedfollowing distal finger amputations. The aim was to correlate prosthetic fitwith the magnitudes of circumference reduction in the finger models used toproduce the prostheses and to identify the optimum reduction for the bestoutcome. A good fit is achieved primarily by making the prosthesiscircumferentially smaller than the segment of the residual finger (residuum)over which it "cups". The percentage reduction in circumference of thefinger model against the residuum model was calculated by dividing thedifference in circumference between the residuum model and the finger model bythe residuum model circumference and multiplying the result by 100.
As a benchmark to facilitate future model modifications, the circumferencereductions that were made on the finger models for this series of patientscan be categorized into three ranges: small (1-3 percent), moderate (5-7percent), and large (8-9 percent). Feedback received from patients aboutloose prosthetic fit during our initial experience with fitting thimbleprosthesis had prompted us to experiment on a larger circumference reductionwhen modifying the finger models. The results of this retrospective studydemonstrated that a larger model circumference reduction of between fivepercent to eight percent is necessary for achieving a secure prosthetic fitand for obviating a subsequent need for rectifying the prosthesis. Thecomplaints in two patients--one with an eight percent and the other with anine percent model circumference reduction--of an uncomfortably tight fitsuggested that eight percent might be the threshold reduction beyond which anexcessively tight fit may result.
Realistic Prosthetic Fingers and Hands - Alatheia Prosthetics
The method of adding layers of silicone on the inner aspect of theprosthesis should be an option for rectifying a loose fit only when theresulting thickened and hence, more conspicuous proximal edge of theprosthesis can be concealed, for instance, by wearing a ring such as in thecase of fitting a full-length finger prosthesis. The use of a ring is,however, not an acceptable means for camouflaging the prosthesis-skinjuncture when fitting a thimble prosthesis since it is not customary to haveone worn anywhere distal to the proximal finger joint. A concern amongst thepatients whose prostheses were thickened was the increased visibility of theprosthesis-skin juncture. The proximal edge of thimble prostheses musttherefore remain thin and translucent to blend with the surrounding skinwithout any need for concealment. In this respect, fitting a thimbleprosthesis calls for good prosthetic fit to be achieved from the outset,without having to subsequently resort to increasing the thickness of theprosthesis. This, in turn, demands that an exacting circumference reductionbe made on the finger models before they were used to fabricate theprostheses.
Ring Finger Prosthesis Pictures to Pin on Pinterest - ThePinsta
Precise circumference reduction of finger models aimed at achieving goodprosthetic fit constituted an integral procedure in the custom-fabricationof thimble-type prostheses for distal finger amputations. In the very fewreports that were identified in the current literature that advocated thefitting of these prostheses, little mention was made concerning the modelmodification and fabrication techniques behind achieving a good prostheticfit, given the constraint of a shorter length (distal to PIPJ) available foranchorage.
Myoelectric Prosthetics Introduction to Upper Limb Prosthetics
Twenty-nine patients (15 males, 14 females) who were fitted withthimble-type prostheses were identified from the prosthetic records (Table1). Their age at the time of fitting ranged between 16 to 47 years (mean,33 years). Seven patients had multiple-digit loss with one involving bothhands. Of a total of 40 finger residua that were fitted, 36 had sufficientlength to allow fitting with a thimble prosthesis. A total of 67 thimbleprostheses were made. In seven patients, the amputation was a result of anold injury with the post-amputation period at the time of fitting ranging from4 to 32 years. For the remaining patients who had sustained a new injury,prosthetic fitting was completed at between 6 to 12 months after the date ofamputation.