Foot Reconstruction 

Updated: Sep 20, 2019
Author: Fabio Santanelli di Pompeo, MD, PhD; Chief Editor: Jorge I de la Torre, MD, FACS 

Overview

Background

Since the conquest of the upright position, the foot has gained more importance as an organ that supports both the lower limb and the whole body weight and that allows humans to stand up, walk, run, jump, and climb.

Human evolution determined progressive changes in the skeletal architecture and the soft tissue of the foot to cope with new environmental requirements. From the orangutan to the chimpanzee, from the gorilla to the human, the most important modifications of the skeleton included the progressive reduction of the distal area of the phalanxes with the loss of the grasping function and the enlargement of the proximal bones (astragalus, calcaneum) to obtain a resistant yet flexible structure. See the image below.

Different evolutions of the foot in primates. Different evolutions of the foot in primates.

The overlying skin and soft tissue, particularly on the foot sole, also changed, acquiring nonshearing and padding properties that made the feet strong and able to support the weight of the body.

Despite these specific and unique features, foot reconstruction has been underestimated for many years, and amputation was considered the treatment of choice for large foot damage until the last century.[1]

History of the Procedure

The history of foot reconstruction began with an attempted morphologic restoration of the shape. The most ancient description is an Egyptian prosthesis found in a pharaoh's sarcophagus. The first written report on foot injuries is found in Roman war surgery books, in which amputation already is suggested as the elective treatment for serious foot damages.

The introduction of antisepsis and analgesia and the anatomic studies of the foot improved surgical treatment. Foot surgery began to be more accurate and sophisticated, as surgeons sought a proper functional reconstruction rather than a pure morphologic restoration of the shape.

Snyder, in 1965, and Kaplan, in 1969, also highlighted the importance of the sensate reconstruction of the foot sole, particularly for weightbearing (WB) areas.

Numerous local flaps have been described to repair small defects, as follows:

  • Simple transposition, rotation, and V-Y skin flaps[2]

  • Fasciocutaneous flaps such as the medial plantar flap ("instep flap"),[3] lateral calcaneal artery skin flap,[4] dorsalis pedis flap,[5] medialis pedis flap,[6] and the first web space

  • Muscle flaps such as flexor brevis digitorum, abductor brevis hallucis, abductor brevis minimi dita, flexor brevis hallucis, and extensor brevis digitorum

  • Lower leg flaps (reverse fascia, sural)

The treatment of large defects remained unresolved until the middle of the 19th century.

  • In 1854, Hamilton described the cross-leg flap, introducing a new method to repair lower limb defects.

  • Filatov, in 1917, and Gillies, in 1920, described the tubular pedicled flap, providing another possibility to avoid amputation.

The advent of microsurgery in the 1970s and the description by Ponten in 1981 of myocutaneous and fasciocutaneous flaps started a new era in lower limb and foot surgery.

  • In 1973, O'Brien (as well as Daniel and Taylor in 1975) described the first free groin flap for reconstruction of the foot.

  • In 1976, Baudet harvested the free latissimus dorsi.[7]

  • In 1976, Harii first transferred a free gracilis flap, and Robinson introduced the dorsalis pedis fasciocutaneous free flap.[8]

  • In 1978, Chang described the radial fasciocutaneous forearm flap.

  • In 1980, Dos Santos first transferred a scapular and a parascapular flap.[9]

  • In 1981, Acland introduced the saphenus flap.[10]

  • In 1982, the rectus abdominis muscle flap first was harvested as a free flap by Cunningham and Bunkis. In the same year, Song described the lateral arm flap.[11]

  • In 1984, Lovie described the ulnar flap and Franklin the deltoid, both of which also are suitable for the foot.

  • In 1984, Song[12]  introduced the anterolateral thigh (ALT) flap, which Wei further popularized as a free flap.[13]

A further refinement in the reconstruction of soft tissue defects came in 1989, when Koshima, Kroll, and Rosenfield, in work based on Taylor's anatomic vascular studies of angiosomes, described the clinical application of perforator flaps, both pedicled or free.[14]  Progress from 1989 through the early 2000s was as follows:

  • In 1989, Koshima [15]  described the deep inferior epigastric artery perforator (DIEAP) flap, which Allen subsequently popularized. [16]
  • In 1990, Taylor [17]  described the posterior tibial artery perforator (PTAP) flap, a pedicled flap.
  • In 1991, Hyakusoku [18]  first proposed the concept of a perforator propeller flap, later sponsored by Teo [19]  for lower limb defects.
  • In 1995, Angrigiani  [20]  presented the thoracodorsal artery perforator (TDAP) flap, to be employed as a pedicle or free flap.
  • In 2003-2004, Wei and Mardini [21] proposed the free-style free flap concept.

A final step in foot reconstruction was achieved with the introduction of free osteocutaneous flaps such as the fibula flap[22] and the iliac crest. While the iliac crest immediately was used for the foot only, in 1983 Taylor first described the reconstruction of the first metatarsal bone by a free fibula flap.[23]

Despite the great variety of flaps, the choice of the most suitable reconstruction remains debated.

Problem

Foot diseases may affect normal life significantly, often requiring long care and expensive rehabilitation programs and representing a burden for society.

In the 21st century, the definition of foot reconstruction must take into account tissue reconstruction, function restoration, and cosmetic rehabilitation.

Which considering large foot defects, the following two questions are mandatory:

  • Can and should this foot be saved?

  • How can the best functional and morphologic recovery be achieved?

The different reconstructive options are discussed in the following sections. The final choice of the most suitable treatment always relies on the preference of the surgeon, but a correct evaluation of the clinical case must be stressed to obtain a successful result.

Epidemiology

Frequency

Foot ulcers are quite common, even if frequency rates are related strictly to different etiologies.

Because of the higher number of vehicle accidents, mostly involving young active people, defects of the foot sole recently have increased.

Traumas to the foot and ankle account for almost 50% of all traumas affecting the lower limb.

Individuals engaged in certain kinds of physical activities (eg, dancers, football players) also are involved in this high incidence rate.

Sex and age affect the vascular pathologies (eg, arteriopathies, Burger disease [90% in males], Raynaud disease [90% in females], venous congestion) and the dysmetabolic anomalies (eg, diabetes). (For more information on the role of diabetes in foot ulcers, visit Medscape’s Diabetic Microvascular Complications Resource Center.)

Tumors of the foot are rare; melanoma is the most common type, and the foot accounts for 5% of its localization.

Etiology

Foot defects can be classified according to etiology into 6 main categories.

Traumas

Traumatic etiology often is correlated to motor vehicle accidents or work accidents. (For more information, visit Medscape’s Trauma Resource Center.) Traumas or injuries may be acute or continued, mild or severe; for example, a mild continued trauma occurs in the foot of dancers. Some occupations require continued use of the foot in a poor mechanical position, thus producing pain and disability; in these patients, the trauma immediately can be repaired only with good circulation.

Trauma also can be intended as a precipitating factor or a factor showing a preexisting situation.

Hidalgo and Shaw divided foot traumas into 3 classes according to dimension and extension of the lesion, as follows[24] :

  • Type I - Small soft tissue loss less than 3 cm2

  • Type II - Large tissue loss greater than 3 cm2 without bone involvement

  • Type III - Large tissue loss with bone involvement

Vascular diseases

Vascular etiology may be due mostly to the artery or the vein circulation. An ischemia or a venous stasis determines a necrosis that often leads to an ulcer.

The manifestations of arterial obstruction are more frequent in males and generally are represented by a dystrophy localized on the distal portion of the foot, involving the toes.

Vein stasis generally is rare on the foot, and these ulcers often are localized in malleolar regions or in WB areas, starting with tissue edema and eczema.

Vascular ulcers usually are painful with a higher risk of bacterial infections.

Metabolic diseases

Metabolic pathologies often induce neurovascular alteration to the whole body. Microangiopathy and neuropathy determine a nonpainful craterlike ulceration localized on the plantar side of the foot, especially in the WB areas.

A bacterial infection by anaerobes is fairly common. The most frequent causes are diabetes, alcoholism, phacomatosis, and gout (podagra).

Tumor

Melanomas, epitheliomas, and sarcomas of the bone or of the soft tissues represent the most common neoplasms that can afflict this region, even if foot tumors are considered rare.

Infection

Infective ulcers often are secondary to traumas, vascular deficiencies, or diabetes. All these pathologies can determine a low peripheral oxygenation and promote anaerobes, gram-negative organisms, and saprophyte infections.

Malformation

Congenital diseases, such as the clubfoot or the bifid spine, are rare. They are associated with deformity of the skeletal and neurologic alterations and easily may determine ulcers on WB areas of the sole.

Pathophysiology

The foot skeleton represents, as a whole, a sort of arch with the medial side higher than the lateral one, limited proximally by two tubercles of the os calcis and distally by metatarsal heads, as shown below. It is the plantar bend/arch. Since the 18th century, anatomic researchers stated that the lateral arch is represented by the os calcis proximally, the cuboid bone distally, and from the last 2 metatarsi (IV and V). The medial arch, higher than the lateral, is formed by the os calcis proximally and by the astragalus distally.

View of the 2 arches of the foot. View of the 2 arches of the foot.

The structure of the foot bones allows some vector lines to be drawn. The direction of the shafts, shown in the first image below, shows that tension planes and pressure planes share the same direction. Shafts demonstrate the 2 arches theory; these follow the direction of the arches inside the bones, shown in the second image below. During the development of human locomotion, the lateral arch acquired the task of supporting the weight in the standing position, rather than the medial arch, which is involved particularly during the walking cycle.

Lateral and medial views of the vectors. Lateral and medial views of the vectors.
Xeroradiography shows the dispositions of the shaf Xeroradiography shows the dispositions of the shafts and the 2 arches theory.

This unique weight distribution has led to the definition of a "metatarsal formula" for the weight pressure distribution. This formula shows that most of the pressure is supported by the fourth and fifth metatarsi (I less than II less than III less than IV equals V) during the erect and bipodalic station that makes a quadrilateral and thus firmly supports the area and from the first metatarsus (I greater than II equals III equals IV equals V) in the monopodalic station that forms a triangular and thus unsteady area.

Recent studies on the plantar pressure distribution with a baropodometer are introducing a new theory on static and dynamic foot movements, suggesting a more important role of the heads of central metatarsal bones, thus changing the metatarsal formula (I less than II equals III equals IV greater than V). This new theory shows that the first and fifth metatarsal bones are used only to avoid lateral and/or medial falls, particularly during monopodalic station (walking cycle).

Presentation

Parameters of clinical examination of foot damage

According to the authors' experience, foot defects can be classified clinically with 4 parameters: extension, depth, localization, and etiology.

Particular attention must be paid to the condition of the surrounding tissue and to neurovascular involvement.

  • Extension - Tissue loss is divided into 2 categories with a different surgical approach, as follows:

    • Small tissue defects less than 3 cm2

    • Large tissue defects greater than 3 cm2

  • Depth

    • Skin

    • Subcutaneous and aponeurosis systems

    • Muscle

    • Bone

  • Localization

    • Anatomic areas (dorsum, medial, lateral side, sole, heel, toes)

    • Baropodometric areas (WB or nonweightbearing [NWB])

  • Etiology - Clinical presentation differs according to the causative agent, as follows:

    • Traumatic ulcers - Irregular shape and margins; possible necrosis for vascular impairment from trauma; normal surrounding tissue; painful; every localization

    • Vascular ulcers - Regular shape (round) and margin for artery impairment and irregular shape and hypertrophic margins for vein, both with damaged surrounding tissue; different localization such as dorsum of the foot or fingers; usually painful

    • Diabetic ulcers - Irregular shape; numerous, callous margins; large damage in the depth and in the surrounding tissue; not painful; more frequent in WB areas

Classification of foot injuries based on anatomy

A new classification based on anatomy and categorized by soft tissue (ST) defects and bone tissue (BT) damage can be created to summarize clinical features and standardize the treatment. (ST types may also be on WB or NWB areas.)

  • Type ST-0 - No tissue damage

  • Type ST-I (calcaneus, dorsal, plantar) - Small tissue defect 1-3 cm2

  • Type ST-II (calcaneus, dorsal, plantar) - Large tissue defect greater than 3 cm2

  • Type BT-0 - No bone damage

  • Type BT-P - Phalanges defect 1-5

  • Type BT-M - Metatarsal defect 1-5

  • Type BT-T - Tarsal defect

  • Type BT-C - Calcaneal defect

Indications

Indications for medical treatment are as follows:

  • ST-I - Small (< 3 cm2) and limited (skin and subcutaneous) soft tissue loss

    • Vascular etiology

    • Metabolic etiology

    • Infections

Indications for surgical treatment are as follows:

  • ST-I - Small (< 3 cm2) and limited (skin and subcutaneous) soft tissue loss

    • Traumatic etiology

    • Neoplastic etiology

  • ST-I - Small (< 3 cm2) involving aponeurosis or muscular layers or even more superficial but resistant to medical therapy

    • By local skin flaps

    • By skin grafts

  • ST-II - Limited (skin and subcutaneous) defects greater than 3 cm2 of nonweightbearing (NWB) areas

    • By local skin flaps, perforator pedicled flaps, or propeller flaps

    • By skin grafts

  • ST-II - Defects of the foot greater than 3 cm2 of weightbearing (WB) areas

    • By perforator pedicle or propeller flaps

    • By free flaps

  • BT-M1, BT-M5, BT-C - Bone loss of WB areas

    • By free flaps

Relevant Anatomy

The foot generally is divided into 4 regions, which are the ankle, sole, dorsum, and toes.

Skin and fat

The skin of the foot, except for the sole, is similar to skin in other regions of the body. The epidermis is thin in the newborn but becomes thicker as a reaction to weight pressure. Hair and sebaceous glands are present only in the dorsum. Eccrine glands are diffused in the sole.

The subcutaneous fat is poorly present in the dorsum but is very thick and granular in the sole, where it is divided by the retinacula. The retinacula are connective fibers between the dermis and the plantar fascia that build a sort of "shock absorber" for the standing position or during movements.

The foot sole consists of 4 layers, which are skin, subcutaneous fat, plantar fascia, and muscles.

The plantar fascia is a strong connective tissue stretched between the inner tubercle of the calcaneum and 5 metatarsal heads. Numerous septi departing from this fascia divide foot muscles into 3 compartments. Muscles for the fifth toe are in the medial compartment, for the big toe in the lateral compartment, and for all the other toes in the central compartment.

Muscles

Foot muscles also are divided by the skeleton into the dorsal side, with extensor brevis digitorum medial and the extensor hallucis laterally, and the plantar side, which is divided into 4 layers. The first layer, the most superficial, is composed of the abductor hallucis, abductor minimi digiti, and flexor brevis digitorum. The second layer is composed of the flexor accessorius and by the lumbricales. The third layer is composed of the flexor brevis hallucis, the flexor brevis minimi digiti, the adductor obliquus hallucis, and the adductor transversus hallucis. The fourth layer, which is the deepest, is composed of the dorsal and plantar interossei.

Skeleton

The skeleton of the foot is composed of 26 bones surrounded by many ligaments to obtain a strong structure. These bones are divided into 3 groups.

The first is the ankle, composed of 7 bones: the rearfoot (astragalus upper and calcaneum lower) and the medial foot (cuboid laterally, navicular medially and internal, middle and external cuneiform distally).

The second group is the metatarsus, composed of 5 metatarsal bones.

The third group is the phalanges, of which 5 are present, composed of 14 bones (3 bones for each phalangis and 2 for the first phalangis).

Apart from these main bones, the sesamoid bones help improve function and are often found as variants of the accessory bones. For more information about the skeletal anatomy, see Foot Bone Anatomy.

Vascularization

The vascularization of the foot can be divided into 3 axes, the anterior tibial pedicle, the posterior tibial pedicle, and the peroneal one. The anterior tibial artery distributes to the dorsal side of the ankle, becoming the dorsalis pedis artery until the back part of the first web space, where it divides into two branches, the dorsalis hallucis and communicating. The other two branches are the tarsal artery upon the navicular bone and the metatarsal artery over the bases of metatarsal bone, where it anastomoses with the tarsal and the external plantar arteries.

This vessel gives off 3 branches. The interosseus arteries receive anastomoses by the perforating branches of the plantar arch; in the cleft between the toes, it divides into 2 dorsal collateral branches from the digital arteries.

The posterior tibial artery passes between the inner ankle and the heel. It divides into 2 branches: the internal plantar artery and the external plantar artery. Numerous calcaneal branches depart behind the Achilles tendon. The internal plantar artery passes forward along the inner side of the foot and the big toe. The external plantar artery passes obliquely to the base of the fifth metatarsal bone; it then turns obliquely inward to the internal between the bases of the first and second metatarsal bones, where it anastomoses with the communicating branch from the dorsalis pedis artery, thus completing the plantar arch. It gives off digital branches.

The third axis, due to the peroneal artery, gives off branches to the posterior side of the ankle and calcaneum.

The veins of the foot are superficial and deep. Two superficial veins are present: the internal, or long, saphenous vein and the external, or short, saphenous vein. They start from a venous arch localized in the dorsum of the foot with a convexity directed forward that receives numerous veins from the dorsum of the toes and the foot. The long saphenous vein passes in front of the inner malleolus, and the short saphenous vein ascends behind the outer malleolus.

Usually 2 deep veins, called venae comitantes, accompany the arteries and their branches. The anterior tibial veins are formed by a continuation upward of the venae comites of the dorsal pedis artery. The valves of these veins are numerous.

Lymphatic vessels are superficial and deep. They superficially accompany the saphenous veins, the deep anterior tibial, the posterior tibial, and the peroneal vessels.

Innervation

The innervation of the foot comes from the saphenous nerve (L2-L3-L4) and from the sciatic nerve (L4-L5-S1-S2-S3) with its branches (the anterior tibial nerve, the external saphenous nerve, and the musculocutaneous nerve).

The anterior tibial nerve accompanies the dorsalis pedis artery, gives off a branch to the extensor brevis digitorum and extensor brevis hallucis, and gives off a cutaneous branch for the superficial area between the first and the second toes. The musculocutaneous nerve supplies the integument of the dorsum of the foot (big toe internal, second toe external, third toe). The external saphenous nerve completes the lateral cutaneous innervation of the foot.

The posterior tibial nerve accompanies the homonymous artery and gives off a sensitive branch for the internal and inferior areas of the calcaneum before dividing itself into the external and internal plantar nerves.

The internal plantar nerve gives off cutaneous branches for the sole and digital branches for the first, second, third, and internal one half of the fourth toe, and it gives off muscular branches for the abductor hallucis, flexor brevis digitorum, flexor brevis hallucis, and the first and second lumbricales. The external plantar nerve completes the innervation of the sole and is distributed to the little toe and lateral one half of the fourth toe.

Muscular branches are for flexor brevis minimi digiti, all interosseus muscles, lumbricales, adductor obliquus hallucis, adductor transversus hallucis, abductor minimi digiti, and accessorius. The internal saphenous nerve gives off cutaneous branches for the medial side of the foot.

Contraindications

Contraindications to medical treatment include neoplastic etiology.

Contraindications to surgical treatment by local flaps or grafts include macroscopic bacterial contamination and necrosis, which require a 2-step procedure: first, clean the foot; second, reconstruct.

Contraindications to surgical treatment by free flaps include severe trauma involving 2 of 3 vascular pedicles of the leg, severe vascular or dysmetabolic disease, poor general conditions, and severe smoking habit.

 

Workup

Laboratory Studies

See the list below:

  • Obtain a complete blood count (CBC).

  • Obtain prothrombin time and activated partial thromboplastin time to check for coagulopathy.

  • Check for blood sugar if suggested by anamnesis.

Imaging Studies

See the list below:

  • Obtain leg and/or foot radiographs for patients with trauma or for osteocutaneous free transfers.

    Radiograph illustrating the dispositions of the sh Radiograph illustrating the dispositions of the shafts in the ankle joint and the heel.
  • Obtain a chest radiograph if indicated by examination findings or the patient's history.

  • Obtain leucocyte lymphoscintigraphy in patients with osteomyelitis.

  • Obtain baropodometric evaluation or gait analysis to identify eventual bone functional loss and to plan a repair of the arches.

    Computerized baropodometry of the foot. Views of t Computerized baropodometry of the foot. Views of the different pressure levels.
  • Nuclear magnetic resonance especially is indicated to study ligaments and joints but also to evaluate the soft tissue damage.

    Nuclear magnetic resonance of the foot. This exami Nuclear magnetic resonance of the foot. This examination best shows bone, joints, and ligaments as well as the soft tissues. Nuclear magnetic resonance is important when making the diagnosis in ankle or heel diseases.

Other Tests

Perform Doppler, echo Doppler, or angiography to assess the vascular pattern of the foot and leg and identify perforators as a possible source of pedicled, propeller, or free flaps.

Perform an Allen test in patients with radial free flaps.

Obtain an ECG in elderly individuals or as per operating room guidelines.

 

Treatment

Surgical Therapy

The following table summarizes the most common surgical options according to dimensions, extension, and localization of the defect.[25, 26, 27]

Table 3. Surgical Options for Foot Reconstruction (Open Table in a new window)

Dimension

Extension

Localization

Type of Flap

< 3 cm2

Soft tissue

Weightbearing areas

Local flap

< 3 cm2

Soft tissue

Nonweightbearing areas

Skin grafts

>3 cm2

Soft tissue

Weightbearing areas

Pedicled perforator or propeller flap, and/or free flap (free fasciocutaneous, musculocutaneous flaps, muscle free flap plus skin graft)

>3 cm2

Soft tissue and bone loss

Weightbearing areas

Free osteocutaneous flap

Local Pedicled or Perforator Flaps

Sole

See the list below:

  • Medial plantar flap (instep flap[3] )

    • Sensitive cutaneous flap harvested from nonweightbearing (NWB) area of the sole

      Medial plantar flap, instep flap (O'Brien and Shan Medial plantar flap, instep flap (O'Brien and Shanahan, 1979).
    • Maximum dimensions - 10 X 7 cm

    • Pedicle - Medial plantar artery either proximal or distally based

    • Arc of rotation - Defect of calcaneum, medial malleolar area, distal weightbearing (WB) areas on the heads of metatarsus

  • Transposition, rotation, and V-Y skin flaps[2]

    • Sensitive fasciocutaneous or cutaneous flaps to cover WB areas

    • Defects less than 3 cm2, with random vascularization

  • Flexor brevis digitorum

    • Muscular flap localized under the plantar aponeurosis, indicated to cover small bone exposure (A sensitive myocutaneous flap also can be harvested.)

    • Pedicle - Lateral plantar artery

    • Arc of rotation - Defect of calcaneum and of medial malleolar area

  • Abductor brevis hallucis

    • Muscular flap along the medial border of the foot

    • Pedicle - Branches from the medial plantar artery

    • Arc of rotation - Medial area of the calcaneum

  • Abductor brevis minimi dita

    • Muscular flap along the lateral border of the foot, larger than the abductor brevis hallucis

    • Pedicle - Branches from the lateral plantar artery

    • Arc of rotation - Lateral area of the calcaneum

  • Flexor brevis hallucis

    • Muscular flap that can be harvested alone or with the abductor brevis hallucis from the medial forefoot margin

    • Pedicle - Medial plantar artery and first web space artery

    • Arc of rotation - Dorsum of the foot, distal forefoot sole on the medial side

  • Island flaps from the toes

    • Sensitive fasciocutaneous flaps from the plantar side of the toes

    • Difficult dissection

    • Pedicle - Digitalis artery

    • Arc of rotation - Distal WB areas on the heads of metatarsus

A study by Struckmann et al indicated that both free and pedicled flaps are equally suitable for the reconstruction of plantar tissue defects. The study, in which 12 free flaps and nine pedicled flaps were used, found that the two flap types yielded essentially the same functional results.[28]

A literature review by Crowe et al found that among reports on reconstruction of the plantar surface of the foot, 53% involved locoregional flaps, with 32%, 10%, and 5% involving free tissue transfer, skin grafting, and multiple methods, respectively. Locoregional flaps consisted most commonly of reverse sural artery flaps, while free flaps most often utilized the latissimus dorsi muscle. The study also found that isolated heel defects were the most frequent plantar foot reconstruction targets and that, regardless of primary neurotization, the majority of locoregional and free flaps demonstrated protective sensation.[29]

Dorsum

See the list below:

  • Dorsalis pedis flap[5]

    • Sensitive fasciocutaneous flap or a myocutaneous flap (including the extensor brevis digitorum muscle) that can be harvested from the dorsum of the foot

      Dorsalis pedis flap, described by McCraw and Furlo Dorsalis pedis flap, described by McCraw and Furlow (1975).
    • Pedicle - Dorsalis pedis artery, which is the terminal branch of the anterior tibialis artery

    • Arc of rotation - Medial or lateral dorsal area, malleolar areas

  • First web space (Gilbert and Morrison, 1975)

    • Fasciocutaneous sensitive flap harvested from the first web space

    • Very small dimensions

    • Pedicle - First web space artery, which is the terminal branch of the dorsalis pedis artery

    • Arc of rotation - Distal dorsum

Medial side

See the list below:

  • Medialis pedis flap[6]

    • Fasciocutaneous flap harvested on the anterior medial axis of the foot

      Medialis pedis flap described by Masquelet (1990). Medialis pedis flap described by Masquelet (1990).
    • Pedicle - Myocutaneous perforator branches from the medial plantar artery

    • Arc of rotation - Medial malleolar area, Achilles tendon

Lateral side

See the list below:

  • Lateral calcaneal flap[4]

    • Cutaneous sensitive flap below the lateral malleolar area along the lateral side of the foot

      Lateral calcaneal artery skin flap, described by G Lateral calcaneal artery skin flap, described by Grabb and Argenta (1981).
    • Pedicle - Lateral calcaneal artery, which is the terminal branch of the peroneal artery; reinnervation is provided by branches from the sural nerve

    • Arc of rotation - Achilles tendon and lateral malleolar area

Lower one third of the leg

See the list below:

  • Sural flap[30]

    • Sensitive fasciocutaneous flap harvested from the posterior area of the leg

      Sural flap; perforator flap from peroneal artery; Sural flap; perforator flap from peroneal artery; described by Donski and Fogdestam, 1983.
    • Pedicle - Sural artery, branch of the peroneal artery

    • Arc of rotation - Achilles tendon and lateral malleolar area

  • Perforator/propeller flap from the peroneal artery.

    • Fasciocutaneous flap along the axis between the peroneus longus and brevis muscles

    • Pedicle - Septocutaneous branches from the peroneal artery

    • Arc of rotation - Lateral malleolar area, calcaneum, and proximal area of the dorsum

      Perforator flap from the peroneal artery. Perforator flap from the peroneal artery.
  • Perforator/propeller flap from the posterior tibial artery

    • Fasciocutaneous flap along the axis between soleus and flexor longus digitorum muscles

    • Pedicle - Septocutaneous branches from the posterior tibialis artery

  • Reverse dermis or fascia flap of the lower leg[31]

    • Dermal or fascia flap harvested from the posterior area of the leg to be skin grafted

    • Pedicle - Random

    • Arc of rotation - Calcaneum, Achilles tendon

Free Flaps for the Foot

Perforator

See the list below:

  • Thoracodorsal artery perforator flap (TDAP)[32]

    • Reliable skin flap, thick skin flap more similar to the skin of the foot

    • Advantages - No donor-site morbidity, long vascular pedicle (>18 cm)

    • Disadvantages - Small diameter of the vessels

    • Pedicle - Perforator of the thoracodorsal artery

  • Anterolateral thigh perforator flap[33]

    • Reliable skin flap

    • Advantages - No donor-site morbidity, large pliable skin flap and sufficient bulk

    • Disadvantages - Small diameter of the vessels

    • Pedicle - Perforator from the descending branch of the lateral femoral circumflex artery

  • Anterolateral leg perforator flaps[34]

    • Advantages - Consistent reliable blood supply and good texture

    • Disadvantages - Small dimensions if direct closure of the donor area is required, small diameter of the vessels, donor-site morbidity, thin skin

    • Pedicle - Superficial peroneal perforators, inferior superficial peroneal artery perforators

Cutaneous

See the list below:

  • Groin flap (Daniel and Taylor, 1973)

    • First flap that was used to reconstruct a defect of the calcaneum

    • Iliac crest region as a donor area allows large flap harvest (30 X 15 cm) with direct closure

    • Disadvantages - Difficult dissection in overweight patients and small diameter vessels

    • Pedicle - Superficial iliac circumflex artery

  • Scapular[9]

    • Can be harvested from the infraspinosa fossa of the scapula

    • Advantages - Easy dissection, long pedicle, large diameter of vessels, direct closure of donor area, possibility of composite flaps combining other muscle flaps

    • Disadvantages - Thickness of the flap and difficult reinnervation

    • Pedicle - Circumflex artery of the scapula

  • Parascapular[35]

    • Harvested in the same area as the scapular flap

    • Shares similar advantages and disadvantages

    • Pedicle - Descendant branch of the circumflex artery of the scapula

Fasciocutaneous

See the list below:

  • Radial (Chang, 1978)

    • Most versatile and used free flap for foot reconstruction that now often is harvested as a pure cutaneous flap

    • Advantages - Easy dissection, long pedicle with large diameter vessels, reinnervation through cutaneous antibrachial nerves, and possibility to combine bone

    • Disadvantages - Mainly due to donor area morbidity that must be closed with a graft

    • Pedicle - Radial artery

  • Lateral arm[11]

    • Thin and small flap that can be harvested from the anterior-lateral area of the lower one third of the arm

    • Advantages - Easy dissection and reinnervation

    • Disadvantages - Small dimensions if direct closure of the donor area is required and small diameter of the vessels

    • Pedicle - Septocutaneous branches from the brachialis profunda artery

  • Dorsalis pedis[8]

    • Previously described as a local flap; also can be harvested as a free flap, but its small dimensions and its pedicle, which is one of the main arteries of the foot, make it a second choice flap

    • Pedicle - Dorsalis pedis artery

Muscular

See the list below:

  • Latissimus dorsi[7]

    • Can be harvested as a pure muscle flap or as a myocutaneous flap; together with the radial flap, often is used for the foot

    • Advantages - Large dimension, easy dissection, long pedicle, and large diameter of the vessels

    • Main disadvantages - Thickness of the flap, which decreases in at least 6 months' time, and sacrifice of major muscle

    • Pedicle - Thoracodorsal artery

  • Gracilis (Tamai, 1971)

    • Muscular or myocutaneous flap (only a small skin paddle) that can be harvested from the medial side of the thigh

    • Easy dissection, vessel diameter of approximately 2 mm, and length of approximately 6 cm

    • Donor area can be closed directly without functional defect; rarely used for the foot

    • Pedicle - Medial circumflex of femoris artery

  • Anterior serratus

    • Muscular flap that is harvested in the lateral side of the truncus

    • Advantages - No sacrifices of significant muscle such as latissimus dorsi, possibility to combine with other flaps, direct closure of the donor area, and long pedicle

    • Main disadvantage - Difficult dissection

    • Pedicle - Branch from thoracodorsal artery

Osteocutaneous

See the list below:

  • Iliac crest[23]

    • Already described as a cutaneous flap; also can be harvested with the bone; includes a double pedicle and a difficult dissection

    • Usually suggested for calcaneum loss or whenever a large amount of bone is required

    • Donor area always closed directly but usually painful in the postoperative period

    • Pedicle - For the bone, profundus iliac circumflex artery; for the skin paddle, superficial iliac circumflex artery

  • Fibula[22]

    • Long and hard bone of the leg that can be harvested for almost all of its length, except for the last 5 cm, without functional impairment

    • More suitable for metatarsal bone loss

    • Dissection not easy for the septocutaneous branches that support the skin paddle

    • Soleus muscle also can be included in the flap

    • Pedicle - Peroneal artery

Preoperative Details

Evaluation of foot injuries mainly must consider the following:

  • Amount of tissue loss (dimension and extension of the defect)

  • Localization (WB or NWB areas)

  • Neurovascular damage

Consider etiology of the defect, age of the patient, concomitant diseases, concomitant leg fracture, and working activity.

A meticulous planning of the defect to be reconstructed can be accomplished with a pattern.

In free flaps, the choice of the recipient vessels depends on the vascular condition of the foot and leg.

Intraoperative Details

See the list below:

  • In patients with limited defects, position the patient supine or prone according to the location of the defect.

  • For major surgical treatment, position the patient according to both the location of the defect and the type of reconstruction to allow simultaneous flap harvest and preparation of the recipient area.

  • Extend the debridement of the defect to vital tissues.

  • Check the actual size of the loss after the debridement.

  • With free flaps, verify the condition of the recipient vessels under magnification.

  • The harvest of the flap can be performed under tourniquet with osteocutaneous flaps such as the fibula.

  • Raise the flap and transfer it to fill the gap.

  • Use drains whenever necessary.

  • Close the donor area according to the surgeon's preference.

  • For propeller perforator flaps from either the peroneal or tibial row, begin the dissection at the level of the identified perforator, taking care not to injury it; after its dissection, outline and harvest the flap.

Postoperative Details

See the list below:

  • Position the patient, possibly on an air or water mattress, with both legs slightly elevated.

  • Monitor the viability of the flap in the early postoperative period according to the reconstructive procedure.

  • For free flaps, monitor every 2 hours in the first 2 days and 4 times per day until 2 weeks postoperatively with the aid of a Doppler probe to check the patency of the microanastomosis and to survey the skin or muscle island.

  • Propeller flaps may suffer from early edema or venous congestion due to pedicle twist. In some cases, venous distal supercharging may be indicated

Follow-up

See the list below:

  • Observe contour and stability of the reconstruction after 2 weeks and 1, 3, 6, and 12 months postoperatively.

  • In patients with defects of the sole, load and walking ability generally are recovered in 1 month.

  • In patients who underwent primary bone reconstruction, load and walking ability are delayed until bone union is achieved, as evaluated with serial radiographs or bone scans.

  • Custom-made shoes can be recommended for 3-6 months.

Complications

See the list below:

  • Complications may be divided into general and specific, and specific complications can be related to the recipient or to the donor area.

  • Generic complications are those related to each surgical procedure (eg, reaction to anesthetics, hematoma, seroma, infection).

  • Specific complications include partial loss of the flap (eg, de-epithelialization of the flap, occasional minor breakdowns of the flap, malunion).

  • In free flap transfers, complications may be divided into 2 groups: complications of the donor area and complications of the recipient area.

  • Donor area complications include hematoma, seroma, skin graft loss, and wound dehiscence. Recipient area complications include partial or total loss of the flap.

  • Early complications mainly are related to vascular problems such as venous or arterious thrombosis and may require a re-exploration of the anastomosis.

  • Late complications are infections and pressure sores due to early recovery under the 100% load. (Click here to complete a Medscape CE activity about pressure ulcers.)

Outcome and Prognosis

A retrospective study by Cho et al indicated that diabetes, chronic ulceration, an elevated platelet count, and an abnormal angiogram increase the risk of reconstruction failure in patients undergoing foot and ankle free tissue transfer. The study involved 231 free flap procedures (in 225 patients) for foot and ankle reconstruction, with the investigators identifying chronic ulceration and an elevated preoperative platelet count as independent risk factors for postoperative foot ischemia (ie, ischemia-related tissue necrosis not occurring at the reconstruction site), and diabetes and an abnormal preoperative angiogram as predictors of flap failure.[36]

A study by Heidekrueger et al reported that in microsurgical reconstruction of the plantar foot, functional outcomes from the use of anterolateral thigh (ALT) flaps and gracilis flaps were similar overall. However, the ALT flaps were associated with significantly less recipient- and donor-site pain, superior sensation recovery, and less scarring, although the rate of secondary surgeries was significantly greater among the ALT patients in comparison with those who received gracilis flaps (39% vs 19%, respectively).[37]

A study by Sato et al suggested that the use of free flaps in the reconstruction of extensive tissue defects from diabetic foot ulcers may increase patients’ chances of achieving independent ambulation. The investigators found that of 23 patients who underwent free flap reconstruction for diabetic foot ulcers (using free rectus abdominis, latissimus dorsi, or anterolateral thigh flaps), 16 experienced successful surgery, with 12 of these individuals attaining independent ambulation.[38]

Other considerations

The treatment of foot ulcers is often difficult, with a relatively high incidence of recurrence, especially in older patients with vascular or dysmetabolic diseases.

Always consider the general condition of the patient in advance to plan the most correct treatment of the local defect. The prognosis is strictly dependent on the age of the patient and the etiology of the defect.

From a surgical point of view, flaps usually give a better result than grafts, with a low rate of breakdowns or recurrence. However, grafts can be remarkably durable on weightbearing (WB) areas and may be the first choice in certain situations.

Even if grafts are advisable in some patients, local flaps provide the most similar tissue and must be the first choice when the defect is not less than 3 cm wide.

The advent of microsurgery and the use of free flaps have changed the approach for the treatment of large defects.

Fasciocutaneous flaps for pure soft tissue loss are versatile and usually offer a suitable paddle of tissue to reconstruct either WB or nonweightbearing (NWB) areas. (Perforator or propeller flaps are elegant alternatives, although they are more technically demanding.) Surgical recovery is fast, and the patient can wear normal shoes early on.

Muscular or myocutaneous flaps must be necessary in large avulsions with bone infection. Surgical recovery with these flaps can be slightly longer, especially because of their thickness, which prohibits the use of normal shoes.

Myocutaneous flaps, particularly bulky in the beginning, usually reduce their thickness in 6 months because of the process of atrophy of the denervated muscle.

Finally, osteocutaneous flaps truly represent the option to avoid amputation, restoring not only the loss of tissue but especially the function of the foot in the gait.

The future of this field will be influenced by new technologies and cellular cultures, with the possibility of reproducing any type of tissue in the laboratory.