Reconstruction of plantar heel defect using reinnervated, skin-grafted flexor digitorum brevis flap

Degloved foot sole successfully reconstructed with split thickness skin grafts

INTRODUCTION

The current opinion is that split thickness skin grafts are not suitable to reconstruct a degloved foot sole. The tissue is too fragile to carry full bodyweight; and therefore, stress lesions frequently occur. The treatment of choice is the reuse of the avulsed skin whenever possible, or else the use of a full thickness fascio-cutaneus flap.

PRESENTATION OF THE CASE

A young male sustained a crush injury to his right foot with deglovement of the plantar surface and part of the dorsum.

DISCUSSION

Split thickness skin grafts are not suitable for full weight bearing, but in special circumstances, certain patients, a lot of time and patience, early mobilization and gradual increasing partial weight bearing it is worthwhile to try. To toughen the foot sole pressure distribution is necessary and can be reached in several ways, soft and springy materials of the inlay, but also socks, orthopedic shoes, casting, orthotics or walking aids.

CONCLUSION

This case-report illustrates that the reconstruction of a degloved foot sole with split-thickness skin grafts can be successful; a silicon inner sole was used to prevent stress lesions.

Neurotized sural flap: An alternative in sensory reconstruction of the foot and ankle defects

INTRODUCTION

The sensory reconstruction of the lower extremity is one of the main goals in lower extremity reconstruction. Reconstructive options endowing sensory recovery are limited. The aim of this report is to evaluate the neurotized sural flap in reconstruction of foot and ankle defects.

PATIENTS AND METHODS

Seven cases that were operated for foot and ankle skin defects with the neurotized sural flap were reported. The largest flap was 10 cm × 14 cm in size. Median age was 38 years. Four defects were on the heel, two were on the ankle, and one was on the dorsum of the foot. The sural nerve was coaptated to a recipient nerve in seven patients.

RESULTS

All flaps survived totally. Follow-up time ranged between 9 and 29 months. All cases had hot-cold perception and two-point discrimination at average 14 ± 1.63 mm at 6th month. Sensory conduction test revealed very low action potentials related to stimulation of the flap.

CONCLUSION

The neurotized sural flap is a versatile modification, for the sensory reconstruction of the moderate size foot and ankle defects.

Versatility of intrinsic muscle flaps for the diabetic Charcot foot

Bone, joint, and/or tendon exposure following surgical debridement of diabetic foot infections requires careful consideration when choosing appropriate closure methods. The unique architecture of the foot, coupled with the functional demands of mobilization, makes soft tissue reconstruction for plantar defects especially challenging. Muscle flaps incorporate the muscle, associated nerve, and vascular pedicles during transposition. This article covers their unique properties for soft tissue coverage in the diabetic Charcot foot.

Innervation of three weight-bearing areas of the foot: An anatomic study and clinical implications

The aim of this cadaver study is to improve our knowledge on the anatomy of the sensory fibres of the three weight-bearing areas of the plantar region. Previous studies mainly focused on the innervation of the heel but the innervation of the other two weight-bearing areas over the most medial and lateral metatarses have been neglected and are not well known. The study was carried out on 10 feet of five male cadavers. The tibial nerve was dissected down to the fat pads over the heel and the first and fifth metatarsal heads under the microscope. The distances of the branching point of the tibial nerve and origins of the medial and inferior calcaneal nerves to a line drawn from the centre of the medial malleolus to the centre of the calcaneous were all measured. The tibial nerve was divided into two branches called the lateral and medial plantar nerves 23.45 mm proximal to the predefined axis. The medial plantar nerve passed underneath the abductor hallucis muscle and gave two sensory branches to the fat pad over the first metatarsal head. The lateral plantar nerve coursed beneath the abductor hallucis and flexor digitorum brevis muscles and supplied innervation of the fat pad over the fifth metatarsal head. The sensory innervation of the heel was provided by medial calcaneal and inferior calcaneal nerves. The medial calcaneal nerve originated from the tibial nerve 41.89 mm proximal to the axis. It divided into two or three branches innervating the fat pad over the heel. The inferior calcaneal nerve originated from the lateral plantar nerve (70%) or the medial calcaneal nerve (30%) 10.66 mm proximal to the axis. This study describes the sensory fibres to the heel and the previously neglected weight-bearing areas over the first and fifth metatarses. Reconstruction of defects in these areas is very difficult so every attempt should be made to protect the sensory fibres during any surgical procedure.

Vascular Anatomy of Plantar Muscles

Many reports on the plantar arteries and the deep plantar arch exist, but none of them focus on the arterial pedicles of the plantar muscles. They mainly discuss the deep plantar arch, its variations, and location. This study plans to determine the location and origin of arterial pedicles of all the plantar muscles as a preliminary study for designing new flaps. The study was carried out on 20 feet from 10 cadavers aged from 35 to 67 years. After an injection of latex via popliteal arteries, dissection of the arteries was carried out under a microscope. Abductor hallucis and flexor hallucis brevis muscles receive their main blood supply from the medial plantar artery; abductor digiti minimi and flexor digiti minimi brevis muscles receive their main blood supply from the lateral plantar artery. The flexor digitorum brevis muscle receives branches from both arteries. Adductor hallucis and plantar interosseous muscles receive branches from plantar metatarsal arteries. Quadratus plantae is directly nourished from a branch of the posterior tibial artery. No distal anastomoses between the medial and lateral plantar arteries were identified, except 1 specimen in which the medial plantar artery made anastomosis with the deep plantar arch. As a result, the arterial pedicles of all the plantar muscles were defined, and based on these findings, new flaps can be planned or existing flaps can be modified.

Heel Reconstruction with a Medial Plantar V-Y Flap

BACKGROUND

Full-thickness defects to the plantar surface of the foot present a challenge to the reconstructive surgeon. Skin grafts and a variety of flap procedures have been described to resurface this site, but not all achieve a return to normal foot function. For the plantar surface of the heel, the previously described medial plantar flap can produce successful results. However, this method leaves a donor site, which requires skin grafting. This is a report of a modification of the medial plantar flap into a V-Y configuration that allows direct closure of the donor site.

METHODS

Three defects of the plantar surface of the heel were resurfaced: case 1, a spina bifida patient with a 45-mm-wide debrided pressure sore; and cases 2 and 3, patients with defects resulting from wide excisions of melanomas that were 47 and 57 mm wide, respectively. Patients in cases 2 and 3 were reviewed at 1 year for mobility, gait, and sensation in the flap.

RESULTS

The patients in cases 2 and 3 were able to attain full, unrestricted mobility and objectively near-normal sensation of the resurfaced skin. In the patient in case 1, a problematic pressure sore was healed after an intermediate period of wound dehiscence, with a robust, bulky flap.

CONCLUSIONS

This modified flap retains the advantages of the traditional medial plantar flap while minimizing its donor-site problems. It has permitted satisfactory long-term functional results, optimizing restoration of foot function, and is a useful option that can be considered for resurfacing the problematic plantar surface of the heel.

Anatomical study of the communicating branches between the medial and lateral plantar nerves

The plantar areas of the foot have specific biomechanical characteristics and play a distinct role in balance and standing. For the forefoot surgeon, knowledge of the variations in the anatomy of communicating branches is important for plantar reconstruction, local injection therapy and an excision of interdigital neuroma. The anatomy of the communicating branches of the plantar nerves between the fourth and third common plantar digital nerves in the foot were studied in 50 adult men cadaveric feet. A communicating branch was present between the third and fourth intermetatarsal spaces nerves in all eight left feet and in six right feet (overall, 28%), and absent in 36 (72%). A communicating branch was found in 14 ft. Ten of the 14 communications were from the lateral to the medial plantar nerve. The length of the communicating branch ranged from 8 to 56 mm (average 16.4 mm) and its diameter was 0.2-0.6 times of the fourth common plantar digital nerve. The angle of the communicating branch with the common plantar digital nerve from which it originated was less than 30 degrees in 11 ft, 30-59 degrees in 27 ft, 60-80 degrees in 8 ft, and more than 80 degrees in 4 ft. Classification of the branch is based on the branching pattern of the communicating branch and explains variations in plantar sensory innervations. We think that the perpendicular coursing communicating branch is at higher risk to be severed during surgery.

Anatomical study of the communicating branches between the medial and lateral plantar nerves

The plantar areas of the foot have specific biomechanical characteristics and play a distinct role in balance and standing. For the forefoot surgeon, knowledge of the variations in the anatomy of communicating branches is important for plantar reconstruction, local injection therapy and an excision of interdigital neuroma. The anatomy of the communicating branches of the plantar nerves between the fourth and third common plantar digital nerves in the foot were studied in 50 adult men cadaveric feet. A communicating branch was present between the third and fourth intermetatarsal spaces nerves in all eight left feet and in six right feet (overall, 28%), and absent in 36 (72%). A communicating branch was found in 14 ft. Ten of the 14 communications were from the lateral to the medial plantar nerve. The length of the communicating branch ranged from 8 to 56 mm (average 16.4 mm) and its diameter was 0.2-0.6 times of the fourth common plantar digital nerve. The angle of the communicating branch with the common plantar digital nerve from which it originated was less than 30 degrees in 11 ft, 30-59 degrees in 27 ft, 60-80 degrees in 8 ft, and more than 80 degrees in 4 ft. Classification of the branch is based on the branching pattern of the communicating branch and explains variations in plantar sensory innervations. We think that the perpendicular coursing communicating branch is at higher risk to be severed during surgery.

Anatomic study of the deep plantar arch

A thorough knowledge of the topography and relations of the plantar arteries is necessary for further advances in arterial reconstruction in the foot. Such reconstruction often avoids amputation in cases of arterial trauma in industrial and automobile accidents, as well as in patients with diabetes and severe ischemia of the lower limbs. Although several studies have addressed the anatomy of the arteries of the foot, there is a shortage of recent studies on surgical vascular anatomy. The deep plantar arch was studied in 50 adult cadaveric feet. It was present in all feet and formed from the anastomosis between the deep plantar artery and the deep branch of the lateral plantar artery. The deep plantar artery was predominant in 48% of the specimens (Type I arches) and the deep branch of the lateral plantar artery in 38% (Type II) with the contribution of each being approximately equal in 14% (Type III). The location of the deep plantar arch can be estimated. The distance between the deep plantar arch and each interdigital commissure was relatively consistent between the subjects, averaging 29% of total foot length. The deep plantar arch was located in the middle third of the foot in all specimens, being in the middle II part of this third in 62%. The mean external diameter of the deep branch of lateral plantar artery was 1.7 mm +/- 0.4 mm. The mean external diameter of the deep plantar artery was also 1.7 mm +/- 0.4 mm. We observed a complete superficial plantar arch in only one specimen (2%). Our findings should assist vascular surgeons in estimating the location of the deep plantar arch from the patient's foot length and in providing other data.

Comparison between sensitive and nonsensitive free flaps in reconstruction of the heel and plantar area

In this study, 12 cases of reconstruction of the heel and plantar area since 1982 are reviewed. Six nonsensate muscle free flaps and six sensate fasciocutaneous flaps were used, respectively. Categories assessed were the time interval for return to daily living activities, sensation to light touch, pinprick, Semmes-Weinstein monofilament test of the reconstructed area for sensory evaluation; and results of pedograms (maximal pressure, pressure distribution, and total contact area of the plantar surface). Follow-up periods were between 2 and 14 years, with an average of 6 years. Better sensory results and early return to daily living activities were observed in the sensate flap group, but the defects were smaller in this group. Despite the slightly longer time to return to daily living activities and worse sensory results, long-term follow-up showed that patients with nonsensate flaps had no difficulty in performing living activities if they continued to be careful and to use some kind of protective shoes. The results of the pedogram analyses were similar between the two groups with regard to total contact area of the reconstructed foot in relation to the healthy foot. Pressure values of the reconstructed areas in sensate flaps were found to be close to pressure values in the same weight areas of the normal foot. The differences between pressure values of the sensate and nonsensate flaps were statistically significant (p < 0.001). Therefore, in reconstruction of the weight-bearing surface of the foot, each case should be evaluated individually. The reconstructive method should be chosen according to the location and soft-tissue requirements of the defect.