Muscle Flaps Flashcards
Mathes and Nahai Classification
Based on muscle vascular supply
Type 1 - 1 vascular pedicle
Type 2 - 1 dominant and 1 minor (most common)
Type 3 - 2 dominant pedicles (allows muscle to be split)
Type 4 - segmental vascular pedicle (most ltd role)
Type 5 - 1 dominant with secondary segmental pedicle (dom near insertion and segmental near origin) - can raise on either ie. reverse LD
Examples of Type 1 Muscle flaps
Gastroc* TFL* VL* First DIO APB Anconeus Genioglossus Hyoglossus Styloglossus Colon Jejunum
Examples of Type 2 Muscle Flaps
Gracilis* Soleus* RF* Biceps femoris Vastus Medialis BR* ADM FDMB FCU Peroneus Longus Peroneus Brevis Platysma Abductor Hallucis SCM Trapezius* Triceps Coracobrachialis
Examples of Type 3 Muscle Flaps
PIGROST P - PecMinor I - Intercostal G - Glut Max R - RA O - Orbicularis Oris S - Serratus Anterior T - Temporalis
Omentum
Examples of Type 4 Muscle Flaps
FFEEETS F - FDL F - FHL E - EDL E - EHL E - External Oblique T - tibialis ant S - sartorius
Examples of Type 5 Muscle Flaps
LIP
L - LD*
I - Internal Oblique
P - Pec Major*
Define - arc of rotation
What determines this?
Arc of rotation:
“reach of flap” or area it covers when raised on pedicle
Determined by:
- extent of elevation of muscle
- location of dominant pedicle in relation to origin and insertion
- # of vascular pedicles
What are choke arteries?
What are oscillating veins?
What are perforators?
Choke arteries:
Small caliber vessels allowing bidirectional flow
Oscillating veins:
No valves - allow reversal of flow
Perforators:
Vesels passing through muscle to supply overlying skin
What is the Mathes classification for vascular supply to the skin?
Type A - direct cutaneous vessels
Type B - fasciocutaneous perforators (thin, narrow muscles ie. sartorius and biceps femoris)
Type C - musculocutaneous perforators (broad, flat muscles)
How to increase survival of muscle flap?
- delay procedure
- avoid distal skin paddles
- define perforators and max. inlc of them
What muscle flap types should you be cautious with when dividing?
TYpe 2 and 4 - minor and segmental pedicles - may jeopardize skin paddle
What are indications for muscle flaps?
- Massive defects
- Ischemic wounds (irradiated, chronic ulcers)
- Obliteration of dead space
- Compond wounds (composite flaps)
- Contaminated wounds (after debridement - well vascularized tissue to decrease bactrerial load)
- Functional sensorimotor flaps (facial reanimation, UE recon)
Advantages of muscle flaps?
- Reliable and sp vascular pedicles
- Bulk
- Pedicle outside of zone of injury
- Resistance to infection
- Possibility of functional restoration
- Malleable
- Different sizes
- Can combined with skin paddle (closure/cosmesis)
Disadvantages of muscle flaps?
- Potential functional deficit at donor site
- Possible unaesthetic appearance at donor site (scars, contour)
- Excess bulk
- Variable/unpredictable degrees of muscle atrophy (~50% of bulk)
Common complications of flaps (local, donor and systemic)?
Local
- flap loss
- epidermal slough
- wound dehiscence
- infection
- hematoma/seroma
Donor
- scar/deformity
- loss of function
- infection
- hematoma/seroma
Systemic
- anaesthetic complications
- DVT/PE
- atelectasis/ pneumonia
- MI
What is the pedicle for the TRAM/VRAM flap?
Origin and insertion of RA?
Pedicle - DIEA or SEA; VCs
O = pubic symphysis
I = costal cartilages 5-7 and xiphoid
How to raise TRAM flap?
Mark in standing position - 7 cm above introitus, midline and ASIS - upper incisons high enough to catch periumbilical perforators
PInch to close when supine
Dissection:
1. Sup incisions - bevel up
2. Dissect abdo flap to costal margin (tunnel if pedicled)
3. Flex bed - make sure you can close - incise inf/ly
4. Raise non-TRAM side (suprafascial to midline)
5. Incise ant rectus fascia (leave 1 cm cuff med and lat)
6. Dissect muscle circumferentially
7. If pedicled, incise sup or inf depending on use - if sup ID and clip DIEA - split ant rectus fascia sup to flap and circumferentially dissect it out
8. If free - dissect out pedicle into groin until VC join and become 1 v. - incise muscle sup and inf
What portion of the LD muscle flap is reliable?
Proximal 70%
What is the pedicle to the LD flap?
Thoracodorsal a and VCs (reverse flap - thoracolumbar perfs)
n = thoracodorsal nerve