GLUTEAL FLAP 

ARTCILES

1)      Michigan – 472)      Mathes – 157

 

ANATOMY

 

VASCULAR SUPPLY1)      Type III vascular supply2)      Major Pedicles:

a.       Superior gluteal arteriesb.      Inferior gluteal arteriesc.       From the internal iliac arteriesd.      Pass superior and inferior to piriformis

 

OPTIONS

1)      can raise as a single flap2)      can raise superior or inferior segments separately

a.       this will preserve ambulation3)      V-Y advancement flap4)      Rotation flap

 

Gluteus Maximus / Posterior Thigh

ANATOMY

1)      most superificial gluteal muscle2)      ORIGIN

a.       Gluteal line of the posterior ilium and sacrumb.      [sacrotuberous ligament]

3)      INSERTIONa.       greater tuberosity of the femurb.      iliotibial band of fascia lata

 

VASCULAR ANATOMY

1)      type 3a.       2 dominant pedicles

ii.  inferior gluteal arteriesiii.      from the internal iliac artery

2)      Both are deep to the gluteus3)      above and below inferior piriformis4)      2 minor pedicles at area of insertion

a.       first perforator of profunda femorisb.      two or three intermuscular branches of the lateral femoral

circumflex vessels

 

NERVE SUPPLY

 1)      MOTOR

a.       inferior gluteal nerveb.      enters with inferior gluteal artery

2)      SENSORYa.       to skin S1-3 mediallyb.      L1-3 laterallyc.       posterior cutaneous nerve of the thigh (S1-2)

i.      supplies the inferior buttocks and posterior thighii.      this can be included in the posterior thigh flap (neurosensory flap)

 

MUSCLE FUNCTION

1)      essential in ambulatory patientsa.       must preserve at least half

2)      extends hipsa.       most powerful extensor of the hip

3)      rotates the thigh laterally4)      important for

a.       runningb.      jumpingc.       climbingd.      stabilizes the pelvis and hip

5)      largest muscle in the body. 

AREAS OF COVERAGE

 STANDARD FLAP

1)      PRESSURE SORE COVERGAEa.       sacrumb.      ipsilateral ischium

 

GLUTEAL THIGH FLAP (Considered Extended If Inferior Gluteal Muscle Included)

 1)      ischium2)      sacrum3)      perineum / vagina

 REVERSE FLAP 

1)      based on perforators from profunda femoris2)      posterior lateral thigh

 

SENORY / FUNCTIONAL TRANSFER 

1)      take inferior muscle with inferior gluteal nerve for sphincter reconstruction (vagina or anus)2)      medially based V-Y advancement maintains sensation3)      posterior thigh flap with posterior cutaneous nerve of the thigh maintains sensation4)      If isolated on its vascular pedicle the flap can cross midline

 TECHNIQUE STANDARD 

1)      MARKINGS  a.       mark the muscle boarders

                                                               i.      sacrum (medial – origin )                                                             ii.      greater trochanter of the fermor (lateral - insertion)                                                            iii.       PSIS (superior - aspect)                                                           iv.       ischium (inferior – aspect )

2)      superior skin island is just inferior to the PSIS3)      inferior skin island is immediately superior to the ischial tuberosity

a.       for patients at risk of recurrent ulcers it is important to design the skin island as large as possible for future re-advancements

4)      incision through skin to identify the superficial fascia - this may be atrophic and hard to identify in patients who have lost gluteal function

5)      with elevation of the muscle the insertion fibers are cut and the muscle elevated lateral to medial

6)      identification of the piriformis is key to dissectiona.       it helps ID siatic nerve and vascular pedicles

7)      when standard superior / inferior gluteal flaps are elevated a lighted retractor to elevate gluteus from piriformis is helpful

 

V-Y ADVANCEMENT FOR SACRAL ULCERS

 1)      generally based only on superior gluteal vessel and superior half of the muscle2)      allows continued ambulation if ambulatory patient3)      For ambulatory patients  Motor innervation is provided by the inferior gluteal nerve (L5 to

S1-2)a.       From sciatic foramen  deep surface of the gluteus maximus muscle at level of

piriformis4)      ELEVATION – Key points:

a.       Division of the entire fibers of insertion or of the superior or inferior half of these fibers is performed

b.      fibers of origin are divided at the lateral edge of the sacrumc.       piriformis muscle is key

                                                               i.      to correct division of the muscle in its midportion for segmental elevation of either the superior or inferior half

                                                             ii.      it is also a guide to the location of the point of entry of the superior and inferior gluteal vessels into the deep surface of the muscle

                                                            iii.      Initial exposure of the pedicle will avoid injury during the muscle division into its superior and inferior halves

                                                           iv.      Can be aided with a lighted retractor 

 

INFERIOR GLUTEAL ISLAND FLAP

 

1)      considered 1st choice for ischial ulcersa.       can be re-advancedb.      large skin paddlec.       closed primarilyd.      not put into tension with leg motion

2)      MARKINGSa.       Mid sacrum to greater tuberosity of the fermurb.      Skin island centered over the gluteal creasec.       Muscle identified at the lateral edge of the ischeal wound

3)      SKIN ISLANDa.       Medial edge = lateral edge of the ischeal soreb.      Design the flap as large as possible without extending into superior gluteal flap or

beyond the greater trochanter of the femur    4)      FLAP ELEVATION5)       it is helpful to widely expose the anterior surface of the muscle first muscle is divided deep

distally, several centimeters beyond the skin island6)       preserve the extension of the inferior gluteal artery and the sciatic nerve as they course onto

the thigh7)       Division of the muscle continues laterally and then superiorly, mobilizing only the inferior half of

the gluteus muscle 

     

POSTERIOR THIGH – Gluteal Thigh Flap

 1)      Based on descending terminal branch of the inferior gluteal artery2)      posterior thigh skin flap based between ischial and greater trochanter3)      axis of the flap

a.       center of the thighb.      inferior gluteal artery as it continues on to the posterior thighc.       line drawn verticallyd.      midway between the greater trochanter and the ischial tuberositye.       perpendicular to the gluteal crease

4)      if < 12 cm in width  direct donor site closure5)      distal tip  to within 8 cm of the popliteal fossa6)      key anatomic structures during the dissection

a.       sciatic nerveb.      posterior cutaneous nerve (S1-3) & inferior gluteal artery

                                                               i.      travel together (medial to lateral) around the ischial tuberosity as they exit the gluteal space

                                                             ii.      lies in the subcutaneous tissue, just below the fascia lata and superficial to the biceps femoris muscle

7)      The skin incision over the distal third of the flap is made down through the deep fascia8)      posterior femoral cutaneous nerve should be identified at the distal midline

a.       descending branch of the inferior gluteal artery is ligated adjacent to the nerve

9)      flap is elevated to the level of the gluteal crease (inferior edge of the gluteus maximus muscle) along the plane deep to the fascia

10)  rotated into the ischial defect11)  traction on the nerve confirms the flap is centered over the nerve which is adherent to the

descending branch of the inferior gluteal vessels12)  to extend the flap length cut the inferior half of the gluteus lateral to the pedicle entrance13)  Blood flow Doppler study can be used to trace the course of the descending branch of the inferior

gluteal artery during the flap design 

  

MICROVASCULAR TRANPLANT

 1)      with microvascular transplant little muscle is taken and the skin flap is based on the superior

or inferior edge of the muscle2)      superior skin flap centered between PSIS and superior sacrum3)      dissect skin off muscle from lateral to medial until perforators are found4)      dissect out the perforators

a.       withb.      or without splitting the superior portion of the muscle

5)      inferior skin island centered over the gluteal crease lateral to the scarum6)      intial incision at inferior aspect of gluteus to identify descending branch of inferior gluteal

artery7)      trace this up to the inferior gluteal artery8)      avoid injury to inferior gluteal of sciatic nerves

  Below: superior gluteal island flap

  

 Below: skin only flap in ambulatory patient, 2 different cases