- See:
-
Phalangeal Menu:
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finger tip injuries
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replantation of the digits
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soft tissue replacement in the hand and forearm:
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upper extremity amputations:
- Basic Principles of Phalangeal Amputation:
- skin incision should be
mid-axial on both sides of digit;
- contour articular condyles - volar and lateral
- if tendon insertion site absent, sever tendon and allow it to retract
- do not suture flexors to extensors
- dissect nerves and sharp proximal transection (gental pull);
- be certain nerves are away from cutaneous scar;
- volar flaps are preferable;
- Quadriga:
- weak grasp in remaining fingers due to
FDP tethering by scar at amputation site (eg suturing FDP to extensors);
- if one
FDP is tethered, the others can not shorten;
- Surgical Technique for Amputation of the Distal Phalanx:
- see:
finger tip injuries:
-
indications:
- amputation and shortening of the digit may be indicated when there is less then 5 mm of sterile matrix, since nail adherence will be losed;
-
nail bed:
- see:
nail bed anatomy
- because the nail matrix extends considerably proximal to skin fold, extensive dissection may be necessary to remove it completely;
- w/ transverse amputations, create distal midlateral incisions on both sides of the digit, to allow easier access to nerves, the phalanx, and to allow easier flap closure;
-
shorten and contour bone for primary closure;
- insertions of flexor and extensor tendons on most proximal portion of the distal phalanx should be left intact if possible;
- if flexor and extensor insertions cannot be left intact, then the distal phalanx should be disarticulated;
- in this case, the flexor and extensor tendons are placed under traction, transected, and are allow to retract;
- a ronguer can be used to contour the volar condyles of the middle phalanx;
- digital nerves are transected as proximally as possible;
- volar skin flap is created & wound is closed dorsally;
- inorder to avoid a club deformity, place the initial suture centrally, and then draw the palmar skin proximally over the dorsal stump;
- incise the overlapping portion of the dorsal skin (which typically extends 45 deg from the central stitch);
- the resulting scar resembles an inverted horseshoe;
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complications:
-
lumbrical plus finger:
- can occur after amputation of the distal phalanx if the lumbrical muscle is not released (along w/ release of the FDP);
- the result is that the FDP becomes a paradoxical extensor of the PIP joint, since the FDP can now act only thru the lumbrical's insertion into the lateral
band (which coarse dorsally into the triangular ligament);
- Amputation thru the Middle Phalanx:
- crushing injury that destroys the distal phalanx and a portion of middle phalanx necessitates amputation
thru the middle phalanx;
- if insertion of
FDS into base of middle phalanx can be preserved, some function of PIP joint may be preserved as well;
- if insertion of the tendon has been avulsed, there is little reason to preserve the middle phalanx, and disarticulation thru
PIP joint may be considered;
- if sharp clean injury, shorten and contour bone for primary closure;
- preserve
FDS insertion;
- Proximal Phalanx Amputation:
- frequently need dorsal skin flap for closure
- intrinsics control flexion;
- lasso procedure:
- one of the flexor tendons (preferably the FDS) is kept long enough to pass around the A2 pulley, when is then sutured back to itself;
- adjust tension, so that full extension is possible;
- Amputation of Finger and Ray:
- occassionally entire finger must be amputated because of severe injury aggressive infection, or malignant tumor;
- ray resection may also be required for traumatic proximal phalanx amputation with
neuroma;
- generally the distal half of the respective metacarpal is resected as well (ray amputation);
- ray resection is most often a consideration in the index finger, however, this is usually done as a staged procedure (allowing the patient to make the decision);
- ray resection can be performed either through a dorsal or volar approach;
- palmar approach to ray resection:
- allows for more cosmetic scar, allows for easier access of nerves (when a neuroma is present), and allows for easier taloring of bone w/ oblique osteotomy;
- technical options of ray resection include resection with or without transposition;
- disadvantages of transposition: patients may be left with decreased grip strength, scissoring of adjacent fingers, and difficulty grasping small objects;
- carpo-metacarpal disarticulation:
- there is no purpose to midcarpal amputation;
- do not save the the proximal row or single carpal bones, esp if amputee is unilateral;
- avoidance of
neuroma:
- consider digital nerve transposition into superficial veins;
- references:
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Index transposition after resection of the long finger ray.
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Total middle ray amputation.
- Functional assessment of ray transfer for central digit loss. L Colen et al. J. Hang Surg. Vol 10-A. 1985. p 232-237.
- Results of central ray resection without bony transposition. JB Steichen and RS Idler. J. Hand Surg. Vol 11-A. 1986. p 466-474.
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Hand function following single ray amputation.
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Results of ray resection and amputation for ring avulsion injuries at the proximal interphalangeal joint.
- Wrist Disarticulation:
- while the stump will pronate and supinate, the socket will not permit this axial rotation;
- this level is useful because of the strong, durable stump, not because of the radioulnar rotation;
Profundus tendon blockage: quadriga in finger amputations.
Intraosseous nerve transposition for treatment of painful neuromas.
Surgery of hand and finger amputations.
A new incision for amputation of the index finger and its metacarpal.
PJ Burnham. Am. J. Surg. Vol 97. p 331. 1959.
