Prescription of prosthetic ankle-foot mechanisms after lower limb amputation.

BACKGROUND: A correct prosthetic prescription can be derived from adapting the functional benefits of a prosthesis to the functional needs of the prosthetic user. For adequate matching, the functional abilities of the amputees are of value, as well as the technical and functional aspects of the various prosthetic ankle-foot mechanisms. There seems to be no clear clinical consensus on the precise prescription criteria for the various prosthetic ankle-foot mechanisms related to the functional abilities of amputees.

OBJECTIVES: To obtain information about aspects of prosthetic ankle-foot mechanisms and daily functioning of amputees with a prosthesis, for appropriate prosthetic prescription criteria.

SEARCH STRATEGY: We searched the Cochrane Musculoskeletal Injuries Group specialised register of trials (April 2003), the Cochrane Central Register of Controlled Trials (The Cochrane Library issue 1, 2003), MEDLINE (1966 to April 2003), EMBASE (1983 to April 2003), CINAHL (1982 to April 2003) and reference lists of articles. No language restrictions were applied.

SELECTION CRITERIA: All randomised controlled trials and quasi-randomised controlled trials comparing different prosthetic devices for lower limb amputation in adults. No language restrictions were applied.

DATA COLLECTION AND ANALYSIS: Two reviewers independently identified potential articles from the literature search. Methodological quality was assessed using a checklist comprising 13 criteria. The reviewers extracted data using pre-defined extraction forms.

MAIN RESULTS: Twenty-three trials were included, with a total of 217 participants. The methodological quality was moderate. Only one study was of high quality. No classical RCT's were identified, yet, all included studies used cross-over designs allowing sufficient control for confounding. In high activity transfemoral amputees, there is limited evidence for the superiority of the Flex foot during level walking compared with the SACH foot in respect of energy cost and, gait efficiency. This benefit has only been confirmed in transtibial amputees during decline and incline walking and increased walking speeds.

REVIEWER'S CONCLUSIONS: There is insufficient evidence from high quality comparative studies for the overall superiority of any individual type of prosthetic ankle-foot mechanism. In high activity transfemoral amputees, there is limited evidence for the superiority of the Flex foot during level walking compared with the SACH foot in respect of energy cost and, gait efficiency. This benefit has only been confirmed in transtibial amputees during decline and incline walking and increased walking speeds. In prescribing prosthetic-ankle foot mechanisms for lower-limb amputees, practitioners should take into account availability, patient functional needs, and cost.