Understand the relationship between anatomy , functions and injuries of the nail bed Develop repair and reconstruction techniques for the injuries and their complications

1. Nail bed injuries

2. Learning outcomes
• Understand the relationship between anatomy , functions and
injuries of the nail bed
• Develop repair and reconstruction techniques for the injuries and
their complications

3. Nail bed lacerations
• Remove nail and inspect nail bed
• Nail fold may be elevated using back
cuts at the corners
• Simple laceration – 7/0 chromic sutures
• Repair under magnification
• Limit debridement – avoids tension on
repair and prevent scarring
• Replace nail plate or cover with artificial
sheet – protects and moulds nail bed

6. Anatomy of the nail complex
Macroanatomy

7. Production of the nail
• Onchyn – keratinous material
produced by the death of the
germinal cells
• Nail growth slows after the
age of 30 years
• Produced in 3 areas
• Germinal matrix – 90%
• Sterile matrix – adherence
• Dorsal roof – nail shine

8. Nail vascular supply
• From volar digital arteries
• Large branch to the pulp
• Branch to the paronychium
• Branch to the proximal nail fold
• Multiple small branches into the nail
bed
• Radial vessels are larger on the ring and
small finger.
• Venous return is in a random fashion
over dorsum

9. Types of Nail Injuries
• Crush injuries
• Sharp laceratons
• likely to result in tip
amputations
• Avulsion
• Iatrogenic
• Inadequate phalangeal
reduction
• Placement of fixation
pins
• Nail biting/ flicking of
the eponychium

10. Basic principles
• Injuries may involve several anatomic structures
• Loss of germinal matrix results in no hard nail growing
• Loss of sterile matrix results in non-adherence
• Radiographs to evaluate assoc. fractures

11. Paronychial injuries
• Simple lacerations – repaired primarily
• Loss of part of the paronychium
• VY advancement
• Cross-finger flap
• Thenar flap
• Dorsal roof laceration
• Primary suture
• Loss of tissue – grafting needed

12. Associated DP fractures
• 50% of nail bed injuries
• Comminuted tuft fractures
• Can be stabilised by the avulsed nail with
figure of eight suture
• Proximal DP # result in nail deformities
• Adequate reduction with crossed K-
wires
• Salter I of the DP can present as avulsed
nail sitting on the eponychium –
accurate reduction needed

14. Subungual Haematoma
• If nail plate still adherent –
trephinization
• Using cautery
• Heated paper clip
• Needle
• Nail bed injuries may be missed
• Partially avulsed nail plate
• Remove and inspect
• Leave in place

16. Complex lacerations
• Accurate determination of the
damaged tissues
• Replace like with like
• Complex stellate lacerations
• Meticulous re-apposition
• Inspect under surface of nail plate

17. Avulsions
• Look under avulsed nail
• In small avulsions replace nail
• Loss of sterile matrix
• Graft from adjacent sterile matrix
• Loss of >50%- graft from toe/adjacent finger

18. Loss of germinal matrix
• Graft of 1cm can take
• Delayed to determine
viability of nail
• Composite graft from
toe/finger
• Acutely – less scar tissue
and better blood supply
but more risk of infection

19. Partial amputations
• Ablate nail bed completely
• Cover the tip
• Shorten the nail bed
• Hook nail - Unsightly and interferes with function
• Loss of nail bed but reasonable bony support – combination of local
flap and nail bed graft

20. Eponychial loss
• After trauma and tumour
resection
• Any excision should be replaced
with a composite graft
• Reconstructing the dorsal roof of
the nail
• split-thickness sterile matrix graft on
the deep surface of the local flap

21. Onycholysis
• Non-adherence
• Caused
• Trauma
• Irritation
• Dissolving of hyponychial plug
• Age
• Onychomychosis
• Scarring in the sterile matrix
• Narrow – excised and primary sutured
• Wide - grafted

22. Split nails
• Longitudinal scar
• Removal of nail
• Narrow, diagonal or transverse –
excision and suturing
• Longitudinal – multiple z-plasties
• Wide
• Split thickness sterile matrix graft
• Full thickness germinal matrix graft
• Split thickness graft of germinal
matrix do not produce nail
• Horizontal scar – double nail

23. Bone irregularities
• Osteophytes
• Post traumatic inclusion cysts of
sterile matrix
• Deformity of nail and erosion of
bone
• Curettage of cysts
• Enchondromas
• Curettage and bone graft
• Fish-mouth incision

24. Nail absence
• Congenital or traumatic
• Skin graft
• Artificial nail
• Microvascular transfer
• Non-vascularised composite graft
• less reliable
• better results in children

25. Tech Hand Up Extrem Surg. 2005 Mar;9(1):42-6.
The aesthetic mini wrap-around technique for thumb reconstruction.
Adani R1, Marcoccio I, Tarallo L, Fregni U.

26. Pincer nail
• Thumb and great toe
• Pain
• Trauma, tight shoes, hereditary
• Nail bed becomes neuro-
vascularly compromised
• Nail removal
• Excision of paronychium
• Freeing paronychium from
periosteum

27. Hooked nail
• Growing nail follows nail matrix
• Tight closure of finger tip amputation
• Loss of bony support
• Absent distal phalanx
• Trim nail bed
• Replace bone
• Shorten nail
• Release pulled over nail bed – V-Y
• Bone graft

29. Antenna procedure
J Hand Surg Am. 1983 Jan;8(1):55-8.
The "antenna" procedure for the "hook-nail" deformity.
Atasoy E, Godfrey A, Kalisman M.

31. Br J Plast Surg. 1992 Nov-Dec;45(8):591-4.
Trimmed second toetip transfer for reconstruction of claw nail deformity of the fingers.
Koshima I1, Moriguchi T, Umeda N, Yamada A.

32. DonorRecipient