Elbow Disarticulation

Question 1

The elbow disarticulation prosthesis is a class 1 transhumeral level full-length transhumeral amputation. This longer amputation has some advantages over a higher level amputation, including:

Answer 1

• the ability of the prosthesis to be suspended over the epicondyles of the humerus.
• the asymmetric contours of the distal residual limb can be captured in the socket to provide rotational control of the socket.
• the amputation is full length, therefore, musculature inserting along the humerus remains intact, increasing both force generation and control of the prosthesis.
• the long lever arm of the humerus contributes to the patients ability to control and generate forces to operate the prosthesis

Question 2

The standard Hosmer outside locking hinges have ___ locking positions. The heavy-duty Hosmer outside locking hinges only have ___ locking positions. The operation of these outside hinges is similar to that of other locking elbows.

Answer 2

• seven, five

Question 3

The socket trim lines should allow maximum abduction of the arm without impingement on the acromion. Medially, the trim line should extend into axilla. Laterally, the trim line should well above the acromion.

Answer 3

False

Question 4

Operation of the elbow disarticulation prosthesis is identical to that of the standard transhumeral configuration and involves a fair-lead control cable with a dual control transhumeral figure of 8 harness. The control motion is primarily humeral flexion and also scapular abduction.

Answer 4

True

Question 5

The long length of the humerus poses cosmetic and functional problems since the residual limb is so long that a standard elbow unit cannot be used since the maximum allowable elbow discrepancy is:

Answer 5

2”