Hand Fingertip Amputations, Dupuytren's, Vascular
Buerger disease
Acquired vasculitis in smokers, often bilateral
Stenosis, ectasis (corkscrew pattern)
Angiogram findings (2) with hypothenar hammer syndrome
Healing by secondary intention
Best method of reconstruction to preserve fingertip sensation
Toe-to-thumb transfer
Best reconstruction for thumb at MCPJ level
Calcinosis Raynaud phenomenon Esophageal dysmotility Sclerodactyly Telangiectasias
CREST syndrome
Extension deficit
Common complication after Moberg flap for thumb reconstruction
>30 mmHg or <30 mmHG difference between compartment pressure and DBP
Compartment pressure indicative of compartment syndrome
Crush injury Multi-level injury
Contraindications (2) to finger replantation
Unstable patient who can't tolerate prolonged operation Patient where amputation and prosthesis would provide better functional result
Contraindications (2) to immediate limb replantation
FDMA flap
Coverage for thumb with denuded tendon
I: 3 months, pain out of proportion, hyperesthesia, edema, hyperhidrosis. II: dystrophic; 3-9 months, pain, stiffness, altered blood flow, hair loss, decreased moisture, osteopenia. III: atrophic; 9-18 months, decreased pain, increased stiffness.
Describe 3 stages of CRPS
Hyponychium
Distal junction of skin and nail
Eponychium
Distal nail fold attached to surface of nail
Trephination
Drainage of subungual hematoma
Little, FDMA 1 year
Fingertip flaps (2) that are innervated and sensate. How long does cortical reorientation take?
First dorsal metacarpal artery flap involving branches of radial artery, superficial sensory branch radial nerve
Flap to provide sensate coverage of thumb. Arterial and nerve supply.
Amputations at proximal phalanx or more distal
For what thumb amputations is distraction osteogenesis useful?
Reverse radial forearm
Forearm flap with pedicle long enough to reach fingertip
3:1 male to female
Gender predominance for Buerger disease
9:1 male to female
Gender predominance for hypothenar hammer syndrome
Homodigital island flap
Good reconstructive option to maintain fingertip sensation
Equivalent
How do rates of replant survival and thrombosis change if vein grafts are used?
By positioning amputated nerve stumps well within remaining muscle and far from cutaneous closure
How does TMR improve prosthesis control?
Sterile matrix adds thin layer of cells to undersurface of nail
How does the nail remain adherent?
2 years 10-11 mm
How long does cortical reorientation take after FDMA flap reconstruction of thumb? What is the average static 2 point discrimination?
6 hours 30%
How soon does a high pressure paint gun injury need to go to the OR? What is the amputation rate?
10 cm
Ideal distal of forearm amputation from wrist to allow for adequate soft tissue coverage
Warm ischemia < 6 hours Cold ischemia < 10 - 12 hours If long ischemia time, perform arterial anastomosis all allow runoff prior to venous anastomoses
Ideal warm and cold ischemia times for limb replantation. What can you do if ischemia time is prolonged?
Volar oblique, as advancement would be inadequate
In what pattern of fingertip amputation is a volar V-Y advancement contraindicated?
Digital ulceration DBI < 0.7
Indications (2) for surgery with hypothenar hammer syndrome
Extended warm ischemia time > 8 hours Combined injury involving both major arteries and veins
Indications for prophylactic fasciotomies of forearm
MCPJ contracture > 30 degrees Any PIPJ contracture
Indications for surgery for Dupuytren contracture
Fracture of hook of hamate
Injury often seen in athletes who use rackets
No
Is innervation transferred in thenar or cross finger flaps?
No
Is reverse radial forearm flap sensate?
Perionychium
Lateral borders of nail
Medial plantar artery fasciocutaneous flap
Local flap for coverage of defects on forefoot/heel
Small finger FDP
Loss of this muscle results in significant loss of grip strength
Antigen antibody complexes activate complement system, causing massive capillary thrombosis, preventing vascularization of graft
Mechanism of action of hyperacute rejection
Myofibroblasts act on collagen bundles deposited by fibroblasts
Mechanism of formation of Dupuytren cords
2cm
Moberg advancement flap can cover thumb defect up to what size
Long finger
Most common fingertip injured
Non-adherence of nail Scarring of nail bed
Most common nail deformity after trauma. Most common cause of this.
Minor intrinsic hand weakness
Most common side effect of Botox A injection for Raynaud's
CRPS Stage II Post-menopausal women
Osteopenia is related to disuse and is a typical finding in which type of CRPS? What demographic is this more common in?
Repetitive blunt trauma to hypothenar eminence causes thrombosis of ulnar artery at Guyon canal. Emboli decrease flow, cause cold sensitivity, ischemic pain, rubor, ulcerations in small and ring fingers.
Pathophysiology of hypothenar hammer syndrome
Germinal matrix
Portion of nail responsible for 90% of new nail growth
Bones, tendons, arteries, nerves, veins Artery first if prolonged ischemia time
Preferred sequence of reconstruction for multiple digits. How might this change?
Takes ~3 months, averaging 0.1mm daily
Rate of nail growth
Does not affect epiphyseal growth Children adapt well to functional deficits Microvascular repair has high success rate
Reasons (3) for replantation in children
Cross finger flap with bone graft
Reconstruction for hook nail deformity
Toe-thumb transfer
Reconstruction for thumb amputation without possibility of replantation
Pollicization of index finger
Reconstruction for thumb avulsion with CMCJ disruption
Volar V-Y advancement
Reconstruction for transverse and dorsal oblique fingertip amputations
<1 mm: scar excision, nail bed advancement, primary closure. >1 mm: scar excision, adjacent finger graft, eponychial fold flap
Reconstruction of scarred nail bed (< 1mm vs > 1mm)
Amputation and avulsion. Replantation with vein grafting.
Roping injury to digit results in what combination of injury patterns? How would you reconstruct this?
Great toe wraparound flap
Sensate reconstruction for skin avulsion of distal thumb with intact neurovascular structures
5-10 cm
Shortest stump length distal to elbow to maintain native elbow motion when fitting prosthesis
Mild: elevation, cold compresses Severe: evaluation of compartment pressures w/ potential decompression
Treatment for IV extravasation with mild symptoms? Severe symptoms?
Graft from 1st or 2nd toe
Treatment for nail bed injury involving both sterile and germinal matrices
Excision and primary closure
Treatment for nail bed scar involving sterile matrix only
FDMA flap for sensate reconstruction
Treatment of large volar thumb soft tissue defect
Local wound care
Treatment of volar thumb soft tissue defect <1 cm
Moberg flap
Treatment of volar thumb soft tissue defect up to 2cm
Acute humoral
Type of rejection that occurs in 3-6 days and is mediated by immune complexes rapidly induced after graft exposure
Acute cellular
Type of rejection that occurs in 3-6 months, mediated by T cells activated against donor antigens, primarily in lymphoid tissue
Hyperacute
Type of rejection that occurs in minutes to hours due to preformed antibodies in recipient
Chronic
Type of rejection that occurs over years and is antibody and cell mediated
Botox A injection
Used to treat vasospastic disorders of digital vessels
Aeromonas infection Invade walls of blood vessels Ceftriaxone Produces beta-lactamase (penicillins and 1st generation cephalosporins ineffective)
What bacteria must be covered for prophylactically when using leech therapy? What capability does this bacteria have? What antibiotic is used to do this? Why this antibiotic?
Nail cell nuclei in germinal matrix stream distally, creating difference in light detection
What causes the lunula of the nail?
Volar soft tissue loss with nail bed folding over residual tip
What is a hook nail deformity?
Paradoxical extension of PIP w/ active flexion due to increased tension on lumbricals from FDP retraction. Treat with division of lumbrical.
What is a lumbrical plus deformity after amputation of finger? How is this treated?
Normal: 0.75 - 0.97 Inadequate perfusion: < 0.7 Tissue loss: < 0.5
What is a normal digital brachial index? What indicates inadequate perfusion? What indicates tissue loss?
Dupuytren's disease affecting pretendinous band, spiral band, lateral digital sheath, Grayson ligament. Displaces neurovascular bundle centrally.
What is a spiral cord? Where is the neurovascular cord displaced?
Non-vascularized bone graft covered with local pedicled flap
What is an 'on top plasty'?
Volar curvature of nail that occurs because of lack of bony support to sterile matrix, typically secondary to trauma
What is hook nail deformity?
Longitudinal nail split, often caused by adherence of nail fold dorsally and nail bed volarly if nail fold not stented open after trauma
What is synechiae? What can cause it?
None Rare 8 weeks post-procedure
What is the incidence of digital nerve rupture during cord injection with Xiaflex? Pulley and flexor tendon rupture? How long until surgical exploration is indicated?
Inhibition of Rho/Rho kinase activity, inhibition of substance P secretion and receptor sensitivity, decreasing activity of chronically up-regulated C-fiber nociceptors
What is the mechanism of action of Botox for treatment of Raynaud?
Skin Acute rejection (type II hypersensitivity) mediated by IgM, IgG
What is the most reactive component of a composite tissue allograft? What type or rejection is this and how is it mediated?
Repair of at least 2 dorsal veins
What is the only factor that influences digit survival in ring avulsion injury?
Neurovascular compression of subclavian vessels and brachial plexus
What is thoracic outlet syndrome?
Only in acute setting to evacuate hematoma
What is trephination of nail appropriate?
Biceps tendon transfer to ulna
What maneuver can decrease risk of flexion contracture at elbow in transradial amputation?
Release checkrein ligaments, then accessory collateral ligament
What should you do in PIPJ remains in flexion after Dupuytren's fasciectomies?
Median nerve Deep to bicipital aponeurosis
What structure can be injured by brachial artery catheterization? Where does this structure separate from the brachial artery?
Sterile matrix
What structure is shortened in hook nail deformity?
1.2 - 1.4mm proximal to germinal matrix
Where do extensor tendons of fingers insert?
Reverse cross finger flap uses only subcutaneous tissue from donor, with FTSG placed over recipient site
Where is the skin graft placed in a reverse cross finger flap?
Limited fasciectomy
Which treatment for Dupuytren's contracture provides the greatest degree of initial correction and longest period prior to recurrence, but also the highest cost?