Axial Flaps lecture 2024.pptx

AXIAL FLAPS OF THE LOWER EXTREMITY John D. Bennett DPM, FACFAS College of Podiatric Medicine and Surgery Des Moines University Thanks to Dr. Pehde and his contribution to this presentation General objectives: Identify wounds of the lower extremity that are appropriate, and meet the criteria for an a...

AXIAL FLAPS OF THE LOWER EXTREMITY John D. Bennett DPM, FACFAS College of Podiatric Medicine and Surgery Des Moines University Thanks to Dr. Pehde and his contribution to this presentation General objectives: Identify wounds of the lower extremity that are appropriate, and meet the criteria for an axial graft Recognize and describe the surgical principles for creating an axial flap. Recognize specific axial flaps for the foot and ankle soft tissue reconstruction. Wound Closure Factors to Consider Diabetic foot and ankle wounds range from the simple to the complex Patients with diabetic wounds are typically complex Many treatment options available Soft Tissue Reconstructive Ladder 1. Secondary Intention Skin Equivalent Grafts Topical Growth Factors Negative Pressure Wound Therapy 2. Primary Closure 3. Split thickness or full thickness skin graft 4. Local random flaps Rotational, V to Y, Translational 5. Regional axial flaps Lateral calcaneal artery, medial plantar artery, intrinsic muscle foot, Perforator 6. Distant axial flaps Reverse sural artery flap, peroneus brevis, hemisoleus muscle flaps *Hyperbaric Oxygen Therapy – adjunctive treatment when indicated during all phases of the reconstructive ladder Soft Tissue Reconstructive Ladder 1. Secondary Intention Skin Equivalent Grafts Topical Growth Factors Negative Pressure Wound Therapy 2. Primary Closure 3. Split thickness or full thickness skin graft 4. Local random flaps Rotational, V to Y, Translational 5. Regional axial flaps Lateral calcaneal artery, medial plantar artery, intrinsic muscle foot, Perforator 6. Distant axial flaps Reverse sural artery flap, peroneus brevis, hemisoleus muscle flaps *Hyperbaric Oxygen Therapy – adjunctive treatment when indicated during all phases of the reconstructive ladder Flap Principles A flap is a transfer of tissue with its blood supply from one part of the body to another – “Robbing Peter to pay Paul.” Flap survives on its own blood supply until new blood vessels from recipient site incorporate into the flap Soft Tissue Flap Classification There is not one unifying classification system to describe soft tissue flaps There is overlap in the description of flaps Can be confusing Soft tissue flaps for reconstruction based on: – Composition of the flap – Type of blood supply supplying the flap – Proximity of the donor tissue to the recipient bed Flap Classifications Composition of the flap – Single component Skin flap Muscle flap Bone flap Fascia flap Flap Classifications Composition of the flap – Multiple component Cutaneous – skin Adipose – fat Fascia – fascia Musculo or myo – muscle Osteo – bone Example of multiple component flaps – Suprafascial – skin, fat containing envelope – Fasciocutaneous – skin, subcutaneous tissue, fascia – Musculocutaneous – muscle, fascia, subcutaneous tissue and overlying skin - Osteocutaneous – bone, fascia, subcutaneous tissue, overlying skin – Adipofascial flap – fat and fascia Flap Composition Osteo-cutaneous flap Flap Classification Blood Supply – Random Do not have a specific or named vessel Blood supply is provided by many small unnamed vessels of the subdermal plexus Flap Classification Blood Supply – Axial Based on named blood vessels that enters the base of the flap and runs along it axis The tissue that is supported is known as an angiosome Peninsular flap contains soft tissue around vessels Island flap has a pedicle made up of vascular structures that are dissected from the soft tissue Free flap – detached at the vascular pedicle and must be reanastomosed to artery and vein at recipient site Flap Classification Blood Supply – Axial Perforator flap – base on a perforating artery in which the vessels are dissected out of the tissue through which they perforate. – Flap harvested without the deep tissue to minimize donor site morbidity and allow for only tissue required for defect Flap Classifications Proximity of flap donor and recipient sites – Local Use tissue that abuts the soft tissue defect Limited by availability of healthy, pliable, well vascularized tissue – Rotational, advancement, transposition, interpolation – Regional Axis flap with a pedicle that used tissue in the vicinity of the defect Derive vascular supply from the same anatomic area of the soft tissue defect – Distant Flaps using tissue far from the defect and can be transferred over a large distance Axis flap with a pedicle or as a free flap Muscle Flaps Muscle Flaps of the Lower Extremity Leave minimal donor site morbidity Easy to dissect Bring immediate blood supply to surgical site Rotate easily Important to understand blood supply to the muscle to allow appropriate rotations Classification of Muscle Flaps Muscle Flaps – Vascular supply – Type I – one vascular pedicle – Type II – one dominant pedicle at origin with minor pedicles entering muscle belly – – – Type III – two major pedicles from separate regional arteries Type IV - segmental minor pedicles along entire length of muscle Type V - one dominant pedicle at origin with several smaller secondary pedicles at insertion Foot and Ankle Muscle Flaps Intrinsic Foot Flaps – Type II muscles with dominant proximal pedicle – Can be used for foot and small ankle deficits – – – – – Extensor digitorum brevis Abductor digiti minimi Abductor hallucis Flexor digitorum brevis Flexor digiti minimi Abductor digiti minimi mucle flap Foot and Ankle Muscle Flaps Distal Lower Leg Muscle Flaps – Type IV muscles with multiple segmental minor pedicles – Can be used for small to moderate sized wounds of the lower leg, ankle, heel and dorsal foot – – – – – – – Soleus Flexor digitorum longus Peroneus brevis Extensor digitorum longus Extensor hallucis longus Peroneus tertius Anterior Tibialis Peroneus Brevis Muscle Flap Type IV Muscle Pivot Point is 6 cm proximal to the tip of the fibula Peroneus Brevis Muscle Flap Courtesy of Dr. Edgardo Rodriguez Peroneus Brevis Muscle Flap Peroneus Brevis Muscle Flap Axial Fascio-cutaneous Foot and Ankle Flaps Lateral Calcaneal Artery Flap – Blood Supply Lateral Calcaneal Artery is typically terminal branch of the peroneal artery, but may arise from posterior tibial artery. Based on cadaver studies Peninsular, regional fascio-cutaneus flap Plastic and Reconstructive Surgery – Global Open: September 2015 - Volume 3 - Issue 9 - p e517 55 year old diabetic female Surgical repair insertional Achilles tendon calcifications Post operative wound dehiscence Treated with local wound care, surgical debridement with application of skin equivalent graft. Wound progressed to full exposure of tendon with necrosis and infection of tendon Aggressive Debridement Bone Cultures Negative for osteomyelitis Wound clean and ready for reconstruction Flap is mapped out with template Flap ready to be raised (4.5 cm x 8 cm) Start at level of calcaneal periosteum to determine dissection Lateral Calcaneal Artery, Lesser Saphenous Vein and Sural Nerve ligated Carefully raise flap Flap ready to be transposed Donor Site Allow to granulate and stage Split Thickness Skin Graft – Negative Pressure Wound Therapy – Lateral heel dell will not be as prominent Immediate Split Thickness Skin Graft – Saves a procedure – Lateral heel dell more pronounced – Graft thickness is.015 “ to 0.20” Reverse Sural Artery Flap The Reverse Sural Artery Flap Originally described by Masquelet in 1992. Based on anastomosis of superficial sural artery with the septocutaneous branches of peroneal artery. – Original study examined saphenous, sural and superficial peroneal nerve courses and their accompanying blood supply to skin. – Conclusions from anatomic study allowed development of neuro-skin island flap 1. Anywhere on the superficial course of a nerve. 2. Includes subcutaneous and deep fascia with N,A,V. 3. Applied concept to six cases with chronic ulcerations, achieving good results. Masquelet et al. Skin Island Flaps Supplied by the Vascualr Axis of the Sensitive Superficial Nerves: Anatomic Study and Clinical Experience in the Leg. Plas Reconstr Surg. 1992;89:1115-1121. Reverse Sural Artery Flap Anatomy Sural nerve descends between the two heads of the gastroc and pierces the deep fascia in the middle third of the leg. The Superficial Sural artery arises from the popliteal artery or from the sural artery. Reaches the sural nerve after 2-3cm and gives off further branch to the skin of upper calf. Superficial sural artery follows the nerve, regularly giving off small branches to it. In lower 2/3 of the leg, it also gives off small branches to the skin. Anastomoses with the peroneal artery are constant. – 5 to 7 cm proximal to the tip of the fibula Reverse Sural Artery Flap Advantages Blood supply is reliable and constant Flap does not sacrifice major artery Can be performed as a single stage or staged procedure – Does not require microsurgical techniques or large surgical team – Wide arc of rotation with many possible sizes and shapes Reverse Sural Artery Flap Disadvantages Sacrifice of sural nerve Potential need for skin graft to donor site Unsightly donor site Could make BKA more difficult to cover if required Component s Median sural artery Small saphenous vein Medial sural nerve All emerge from popliteal fossa and lay superficial to gastrocnemius in deep fascia Why its called a reverse sural flap… Arterial blood exits sural artery via perforators Pedicle 7 cm Perforating Arteries to Peroneal Artery Lateral Malleolus Arterial and venous blood flow is now reversed Arterial blood enters sural artery via perforators Case Outlining Defect Tracing defect proximally Flap design with measurement Doppler and Mapping of Sural Artery Flow Proximal Dissection Raising Flap Flap Placement >4cm donor area = Skin graft STSG 2 weeks Post-Op Venous Congestion 10 weeks Post-Op. Skin slough with incorporation of deep fascia layer. Healthy Granulation Tissue present. Status post STSG at 16 Weeks Post-Op Delay component of Reverse Sural Arterty Flap Raise the flap at donor site, then resuture in place Raised flap left in place for 7-10 days, after which flap is transferred to defect site – Longer than 10 days  increased flap stiffness Convenient when treatment calls for multiple operations – Malignant tumors – Severe trauma – Infected wounds – osteomyelitis Why Delay? Enhances perfusion to the flap via pedicle prior to transfer, thus increasing flap viability Decreases incidence of total flap necrosis, venous congestion Recommended for: – Increased risk of flap necrosis Size and position of flap Intraoperative flap perfusion Cardiovascular risk factors Cause of defect – Large, high risk flaps in context of multistep surgical approach Medial Plantar Artery Flap Anatomic Basis of Plantar Flap Design: Clinical Applications Plastic and Reconstructive Surgery Nov 1986 Based on anatomic studies of plantar neurovascular supply Large flaps can be raised superficial to the plantar fascia Based on the proximal plantar subcutaneous plexus – Large –diameter vessels run in medial to lateral circumferential direction Forefoot – dorsalis pedis Hindfoot – calcaneal branches of posterior tibial and peroneal arteries Shaw and Hidalgo Anatomic Basis of Plantar Flap Design: Clinical Applications Plastic and Reconstructive Surgery Nov 1986 Shaw and Hidalgo Anatomic Basis of Plantar Flap Design: Clinical Applications Plastic and Reconstructive Surgery Nov 1986 10 patients with 11 deficits Average size 3.0 x 3.6 cm 2 were diabetic Plantar flaps superficial to plantar fascia and medially based Average follow up 20.8 months Complications – Hematoma – Minor skin breakdown Shaw and Hidalgo Case 1 Diabetic male with history of ulcer for 2 years Started with lymphedema wrap causing a blister on the plantar heel which progressed to a chronic non-healing ulcer Treatment – Multiple debridements – Negative pressure therapy – Offloading (compliance issues ??) Was set up for a calcanectomy….but never happened and showed up in clinic Revision performed at 10 days due to mild abscess and hematoma after restarting coumadin Fasciocutaneous Island Flap Based on the Medial Plantar Artery: Clinical Applications for Leg, Ankle and Forefoot - Plastic and Reconstructive Surgery Jan 1990 Authors eloquently described a medial plantar fasciocutaneous island flap in non-diabetic Able to cover plantar forefoot, plantar heel, posterior ankle and lower leg Size variable from small 3 x 4 cm to larger 6 x 11 cm All flaps viable at follow up (6 months to 5 years ) Baker, Newton and Franklin Medial Plantar Artery Pedicle Flap 60 year old ESRD diabetic male with heel ulcer Multiple debridements Friable granulation tissue with bone exposed Full resection of the achilles tendon leading to unstable hindfoot and ankle with calcaneal gait Complications of Axial Flaps Venous congestion Ischemia to flap Pressure and traction forces to flap and the pedicle Respecting medical comorbidities of patients Have medicinal leeches readily available to apply within 12 to 24 hours as needed Recommend antibiotic coverage for Aeromonas hydrophilia Check hemoglobin and hematocrit levels regularly Leeches typically feed for 30 minutes – once done, dispose in biohazard container after placing in alcohol Thank you