SOCKET VARIANTS IN UPPER EXTREMITY PROSTHESIS

1. Poly Ghosh
NILD, KOLKATA

2. SOCKET
 One of the single most determining factors of whether a person will use a
prosthesis is prosthetic socket design.
 socket designs and careful consideration of residual limb presentation sets
the stage for patient success-
1. maximizing range of motion.
2. providing stability throughout daily activities.
3. comfortably distributing the forces exerted on the residual limb during
movement and suspension.
 Socket design for body powered prosthesis-
1. Harness suspended
2. Self suspended

3. AMPUTATION LEVELS
1. Transphalangeal amputation
2. Transmetacarpal amputation
3. Transcarpal amputation
4. Wrist disarticulation
5. Transradial amputation
6. Elbow disarticulation
7. Transhumeral amputation
8. Shoulder disarticulation
9. Interscapulothoracic disarticulation

4. Transphalangeal amputation ,Transmetacarpal amputation
and Transcarpal amputation (partial hand amputations)
 No prosthetics intervention
 Passive prosthesis
 A body powered prosthesis
 An externally powered prosthesis
 Multiple tasking specific prosthesis
passive prosthesis

5. Electric partial hand prosthesis
Task specific prosthesis

6. Socket design for partial hand amputation
 Socket designs for partial hand prostheses preserve function of wrist joint
and other proximal jt.
 Trimlines and socket contours are generally dictated by the geometry of
the remaining portions of the hand and fingers.
 Goals:-
1. Protection of the residual limb.
2. bimanual stability
3. provide acceptable cosmesis and durability

7. TRANSRADIAL AND WRIST DISARTICULATION
SOCKET DESIGN
 Socket designs fall into four categories:-
1. Supracondyler brims
2. External suspension sleeves
3. Suprastyloid suspensions
4. Internall roll-on locking liners

8. SUPRACONDYLER DESIGNS
1. Muenster socket
2. Northwestern supracondyler socket
3. Modified supracondyler brim
4. Floating brim suspension

9. MUNSTER SOCKET
 Self suspended
 Short Transradial amputation.
 The forearm was set in a position of initial flexion
(average 35 deg.).
 The anterior trim line extended to the level of the antecubital
fold, a channel for the biceps tendon.
 The posterior aspect of the socket enclosed the olecranon.
 The trim line was just above the level of the epicondyles.

10. BIOMECHANICAL FUNCTION
 Range of motion- 35 deg. to 105 deg. Flexion.
 No active pronation and supination.

11. ADVANTAGES & DISADVANTAGES
 Adv:-
1. Comfort and security.
2. Lifting and holding forces generally superior.
3. "Axial load"—resisting vertical downward force with the elbow extended.
 Disadv:-
1. Active pronation & supination is eliminated.
2. Difficulty in donning and doffing as stump length increases.
3. Decrease in flexion range required modification in case of bi-lateral
socket.

12. NORTHWESTERN SUPRACONDYLER SOCKET
 Accommodate all lengths of transradial amputations.
 Provide an improved range of motion at the elbow.
 Narrow M-L
 Anterior trimline is below antecubital area,
 The anterior trimline, superior to the humeral condyles, should be at least
3/8 inch smaller than the measured M-L dimension at
the humeral condyles.
 Posterior trimlines be well rounded to accept
The contour of the upper arm, proximal to the
Humeral condyles. 1/2inch over the olecrenon process

14. MODIFIED SUPRACONDYLER BRIM
 Mainly for myoelectric Transradial prosthesis.
 For long transradial amputations.
 Has a olecrenon cut-out.
 Also called three-quarter type below-elbow socket.
 Cut-out length should not exceed 50% of the axial
stump length.

15.  Adv:-
 Ventilation greatly improved,
 The skin of the stump remains dry making for a cooler socket in the
summer and a warmer stump in the winter.
 Skin problems caused by maceration are eliminated
 Comfort and wearing tolerance are greatly improved.
 Suspension improved
 Anatomical elbow is free to move.
 Increased elbow flexion range.
 Reduced bulkness at olecrenon areas.
 Cosmetically pleasing.

16. FLOATING BRIM SUSPENSION
 For long Transradial amputations and wrist disarticulation.
 Provides some natural rotation at the wrist and allows for maximum
elbow freedom and movement

17. EXTERNAL SLEEVE SUSPENSION
1. Latex rubber or silicone sleeves – atmospheric pressure suspension
2. Neoprene sleeves - atmospheric pressure and skin traction
3. Elastic sleeves- skin traction suspension socket

18. SUPRASTYLOID SUSPENSIONS
 For wrist disarticulaion with prominent styloid process
1. Silicone bladder suspension- Allow volume adjustibility of stump.
2. Window/door suspension

19. INTERNALL ROLL-ON LOCKING LINERS
1. Shuttle lock system- For short and midlength transradial amputation
2. Lanyard locking system- long transradial amputation and wrist
disarticulation
 Terminate distal to epicondyles

20. TRAC SOCKET
 In 2003, Miguelez et al. Described this socket.
 Incorporates design elements from both the muenster and northwestern
interfaces with more aggressive contouring of the anatomy to maximize load
tolerant areas of the residual limb.
 Compression anterior and slightly inferior to the epicondyles, specifically
about the radial head on the lateral aspect.
 On anterior/posterior plane, suspension is achieved by
compression into the cubital fold and supra-olecranon region.
 The TRAC retains the high olecranon encapsulating posterior
trim line
 The anterior trim line extending to the cubital fold with a
channel that allows relief for the biceps tendon.
 Relies on hydrostatic pressure.

21.  The TRAC addresses the deficits of previous designs by contouring five
key areas:
 1) the antecubital region,
 2) the olecranon region,
 3) the epicondylar region,
 4) the distal radial region, and
 5) the wrist extensor and flexor musculature
 The position and degree of displacement of the skeletal substructure while
wearing the TRAC interface are less affected during loading

22. TRIMLINE
 Anterior:- follows the cubital fold.
 Medial and lateral:-should parallel the medial border of the ulna and the
lateral border of the radius.
 Posterior:-approximately 12 to 18 mm proximal to the superior aspect of
the olecranon, with a width similar to the width of the olecranon

25. CRS SOCKET
 Compression/release stabilized socket
 Longitudinal depressions added in the socket walls with
open release areas between the depressions that receive the
displaced tissue .
 Reduce motion of the underlying bony structures with
respect to both the socket and the rest of the prosthesis.
 The depressions and releases during cast-taking but only
by radically changing the way casts are taken.
 Requires selective pressure during cast-taking.

26. ELBOW DISARTICULATION & TRANSHUMERAL
SOCKET
 Socket design will vary with the length of the residual limb and
suspension method.
 Different design:- Elbow disarticulation
1. Windowed socket
2. Screw-in socket
3. Flexible open frame
4. Fenestrated

27. Windowed socket
screw-in socket

28. TRANSHUMERAL DESIGN
 OPEN SHOULDER ABOVE ELBOW SOCKET
 CLOSED ENCASULATED DESIGN

29. CONVENTIONAL TRANSHUMERAL SOCKET

30. OPEN SHOULDER ABOVE ELBOW SOCKET

31. ACCI SOCKET
 Reduction in the lateral trim line of the socket
 An aggressive modification into the deltopectoral groove anteriorly
 a flattened socket just inferior to the spine of scapula,
 A firmly compressed anterior-posterior (AP) dimension for
rotational control along the humeral axis .
 A compressed medial-lateral (ML) dimension at the level of
the axilla

32. Humeral AP clasp design
 Wedge shaped cross-section in the midsection of the socket.
 Humeral shaft lies in the angle of the wedge.
 Flattening lateral aspect of the anterior and posterior
socket walls creates the sides of the wedge.

33. CRS SOCKET
 The antirotation wings are based on original
design of ACCI socket.
 But this wings are smaller for added stability.

34. Shoulder Disarticulation Socket Design
 Infraclavicular socket:-
 Does not enclose shoulder to support
The weight of the prosthesis
 Relies on deltopectoral muscle group aneteriorly
And scapular region posteriorly.
 Less noticeable under the clothing.
 Acrmioclavicular complex free to move within
the socket.

35. TRANSHUMERAL LEVEL BPI ANTERIOR SOCKET
FRAME

36. X-Frame socket
 Uses very rigid material.
 Full contact socket for amputations at the shoulder disarticulation,
interscapulothorasic level and amputation at the level of humeral
neck
 Covers far less surface area, all superflous material has been
removed including the rigid portion of a traditional socket. Which
usually covers the superior aspects of the trapezius.
 Resembles an “x” with its four corner roated inwardly to
compress the anteroposterior aspects of thorax superiorly and
inferiorly.
 It uses outtrigger principles
 Superior compression improves suspension via a wedge effect on
anterior and posterior part

37.  Scapulospinal suspension is provided through posterior
superior strut which rest on the soft tissue near the
medial aspects of the scapular spine
 Anterosuperior part provides pressure over the
deltopectoral region
 An anteroinferior extension that dissipates both shear
and compressive force under load
 A pliable saddle over the trapezius that act as a
suspension strap and an elastic memebrane which
maintained electrode contact even when wearer moves
the prosthesis through a wide range.

38.  It permits the user to bend forward and to
move the shoulder while maintaining good
contact with electrodes.
 It stabilizes the prosthesis against rotation
at its superior and inferior borders
 Adv:
 Greater stabiliity, heat dissipation, comfort
and kinesthesia
 Better appearances

39. Perimeter frame-type socket
 Made out of aluminium.
 Cut-out at anterior,posterior and acromioclavicuar
regions.
 did not use anatomic contouring

40. Microframe-base socket
Shoulder
joint
attachment
location
Anterior deltopectoral
groove and posterior
suprascapular
contouring
Rotational torque
prevention through
anatomical
contouring

41. Upper-arm all-silicone base socket with embedded flexible
fabric electrodes and a socket common connector plate.

42. Hybrid base socket with microframe and silicone inner
socket.

43. Reference
1. The Munster-Type Below-Elbow Socket, an Evaluation, Artificial Limbs,
Vol. 8, No. 2, pp. 4-.14, Autumn 1964.
 The Northwestern University Supracondylar Suspension Technique for
Below-Elbow Amputations,
 Prosthetic sockets stabilized by alternating areas of tissue compression
and release , JRRD Volume 48, Number 6, 2011 Pages -679–696 .
 Atlas of prosthetics, 4th edition
 Advances in Sockets, inMotion Volume 13, Issue 5 September/October
2003
 Shoulder Region Socket Considerations, Troy Farnsworth, CP, FAAOP, et
all. Volume 20 • Number 3 • 2008 93