A programmable tool operable to adjust an external fixation strut (200, 200', 200", 200"') having a rotatable adjustment mechanism for length adjustment, the programmable tool comprising: an output shaft; a motor operable to rotate said output shaft; a first coupling portion solidly attached to said output shaft and adapted to releasably engage with a corresponding second coupling portion of the rotatable adjustment mechanism, thus enabling torque transmission from the motor to the rotatable adjustment mechanism; wherein the first coupling portion and the second coupling portion are a wrench socket and a tip matching the wrench socket, or the other way around; a controller configured for driving said motor according to a prescription comprising instructions for adjusting the external fixation strut (200, 200', 200", 200′′′); a first connecting portion in electrical communication with said controller and adapted to electrically connect with a second connecting portion of the rotatable adjustment mechanism when the first coupling portion is engaged with the second coupling portion, thus enabling data transmission from the external fixation strut (200, 200', 200", 200′′′) to the controller; wherein said first connecting portion is peripheral with respect to the wrench socket or tip making up the first coupling portion; characterized in that it further comprises a front muzzle featuring an annular recess surrounding the wrench socket or tip making up the first coupling portion, said first connecting portion comprising at least one inner connector, placed at a bottom of the annular recess, and at least one outer connector, placed on an outer lateral surface of said annular recess. an output shaft; a motor operable to rotate said output shaft; a first coupling portion solidly attached to said output shaft and adapted to releasably engage with a corresponding second coupling portion of the rotatable adjustment mechanism, thus enabling torque transmission from the motor to the rotatable adjustment mechanism; wherein the first coupling portion and the second coupling portion are a wrench socket and a tip matching the wrench socket, or the other way around; a controller configured for driving said motor according to a prescription comprising instructions for adjusting the external fixation strut (200, 200', 200", 200′′′); a first connecting portion in electrical communication with said controller and adapted to electrically connect with a second connecting portion of the rotatable adjustment mechanism when the first coupling portion is engaged with the second coupling portion, thus enabling data transmission from the external fixation strut (200, 200', 200", 200′′′) to the controller; wherein said first connecting portion is peripheral with respect to the wrench socket or tip making up the first coupling portion; characterized in that it further comprises a front muzzle featuring an annular recess surrounding the wrench socket or tip making up the first coupling portion, said first connecting portion comprising at least one inner connector, placed at a bottom of the annular recess, and at least one outer connector, placed on an outer lateral surface of said annular recess.