Finger Soft Tissue Injuries

Detipping Injury

 

Definition

 

Distal to insertion of flexor and extensor tendons

 

Anatomy

 

Thick skin

- fibrofatty tissue

- fibrous septa from dermis to periosteum of skin

 

Nail complex

 

1.  Nail Plate

 

2.  Nail Bed

- adherent to thin periosteum of P3

 

A.  Proximal germinal matrix

- proximal part

- limit is semilunar lunula

- produces 90% thickness of nail plate

 

B.  Sterile matrix

- adherent to nail plate

- contributes little to thickness

 

3.  Paronychium

- surrounding skin on dorsum of fingertip

 

4.  Eponychium 

- covers nail plate proximally

 

5.  Hyponychium

- thick skin below distal edge of nail

 

Classification

 

A Oblique facing up

B Transverse

C Oblique facing down

D Oblique facing laterally

 

Tissue involved

- Pulp only

- Nail bed

- Bone

 

Goals

 

1.  Preserve functional length 

2.  Preserve useful sensibility

3.  Prevent Neuromas

4.  Prevent joint contractures

5.  Short morbidity with early return to work

 

Management Pulp Loss

 

Pulp loss Finger

 

Options

 

1.  Primary healing

- best option

 

2.  Secondary healing

- < 1 cm2 area to cover

- 90% 5 year satisfaction

 

3.  Skin grafting

- 50% 5 year satisfaction

- most are painful

 

4.  Flaps

 

Local flaps / VY flaps

- Atasoy single volar

- Kutlers lateral flaps

 

Regional Flaps

- Cross-finger

- Thenar flap

 

4.  Formalisation

 

If bone on view and patient doesn't want flap

- take bone to level distal to extensor / flexor tendons

- remove nail bed in full (bilateral eponychial incisions)

 

Bone on View

 

Options

 

1.  Shorten and cover

2.  Preserve length and flap

3.  Secondary intention

- rarely a good option except in children

 

Soft tissue defects Finger

 

Local Flaps

 

1.  Atasoy  VY flap

 

Advantages

- local

 

Disadvantages

- often tender and sensitive long term

- can advance only 1 cm

- suitable for defects < 1 cm

 

Technique

- nibble bone back

- incise skin in V

- must release all fibrous septa form distal phalanx

- attempt to leave small vessels

- check is bleeding

- if avascular is usually because have not released all fibrous septa

- leaves too much tension on vessels

 

2.  Kutler's bilateral VY flap

 

Similar concept

- on both sides of digit

 

3.  Modified Kleinert flap

 

Lateral VY flap

- based on digital pedicle

- more volar VY flap than Kutler's

 

Regional Flaps

 

de-puplped finger injury

 

Disadvantages

- 2 stage procedure 

- Often result in finger stiffness

- Contra-indicated if diabetes / vascular disorders

- age relative contra-indication > 40 years

 

1.  Cross finger flap

 

Rectangle of donor skin from dorsum of P2

- Hinge is mid-axial line

- Must preserve paratenon over extensor tendon

 

Full-thickness skin graft to donor site from forearm

- transversely across bicipital groove

- must remove all fat from FT graft

 

Graft sutured 75% onto dorsum of donor finger

- flap crossed onto distal finger pulp

 

Divide flap under GA 3 weeks later

 

Results

- Obtain 10mm 2 point discrimination of flap

 

2.  Thenar flap

 

Indications

- source of good quality skin

- very similar to finger pulp

- 2 cm defect

- IF / MF / RF

- often difficult to oppose LF

 

Most important point is site of flap

- Position it high and parallel to MP crease

- If low or palmar can get debilitating donor site tenderness

 

Make skin 1.5 x defect size to reconstruct pulp

- donor site closed primarily or FTG

 

3.  Abdominal Flap

 

Suture finger to border between chest / abdomen

- release 3 weeks later

- primary closure of chest wound

 

4.  Formalisation

 

 

B.  Soft Tissue Defects Thumb

 

Options

 

1.  Moberg advancement Flap

 

Indications

- only for thumb

- Cover 2cm defect

 

Technique

- mid-axial incisions from injury site to MPJ

- entire volar skin flap with both NV bundles

- flex IPJ, suture

- can do VY at base, or transverse incision and FTG at base

 

2.  Cross Finger Flap from Index Finger

 

3.  Littler Neurovascular Island flap

 

Ulna side of ring or little finger

- take on just one side

- significant secondary defect

- put a skin graft into secondary defect

- rarely first choice

 

3.  First dorsal Metacarpal Artery Flap

 

Technique

- skin over dorsum of P1 of IF

- 4-sided cut and mobilise on pedicle

- With art vein and nerve

- subcutaneous tunnel

 

4.  Free tissue transfer of great toe pulp

 

5.  Abdominal Flap