British Journal ofPlastic Surgery (I 990). 43, 29&295 0 1990 The Trustees of British Association of Plastic Surgeons

0007-1226/90/0043-0290/$10.00

Reverse vascular pedicle digital island flap T. KOJIMA,

Y. TSUCHIDA,

Y. HIRASE and T. END0

Department of Plastic and Reconstructive Surgery, Jikei University School of Medicine, Tokyo, Japan

Summary-In 7 cases involving 8 fingers, amputation of the distal phalanx of the finger with defects of the pulp were covered by island flaps with the digital vessels acting as reverse vascular pedicles. The survival of the island flap was successful in all cases. The vascularisation of the island flap is derived from the digital palmar arch which is the anastomosis between the radial and ulnar sides of the finger. This method uses a single operative field and covers the defect with volar skin having similar qualities. However, due to problems in sensory recovery, we limit the indications for this method to the middle, ring and little fingers of the non-dominant hand.

To cover amputation stumps or pulp defects of fingers we have recently applied island flaps using the digital artery as a reversed vascular pedicle and obtained satisfactory results (Kojima et al., 1986). The radial and ulnar digital arteries are connected by the digital palmar arch crossing the middle phalanx of the finger. Using this digital palmar arch, the skin of the proximal phalanx of the finger can be elevated as an island flap with a distal vascular pedicle and then transferred to the distal phalanx of the finger. This study reports 7 clinical cases with a description of the surgical technique, and discusses the advantages and disadvantages of this method.

defect and the donor defect closed with a full thickness skin graft from the cubital fossa, using a tie-over dressing (Fig. 1C). This operation was performed in 7 clinical cases involving 8 fingers (Table 1). All the patients were male and aged from 25 to 58 years. The affected side was the right in 3 cases and the left in four. Six middle fingers, one index finger and one ring finger were involved. Flaps were applied to pulp defects in 6 fingers, to an amputated stump in one finger and to a fingertip defect in one finger.

Illustrative case reports Case 1

Surgical technique The skin island flap is designed at the base of the proximal phalanx of the finger according to the pattern of the amputated stump and the skin defect of the pulp (Fig. 1A). Following this design, the skin incision is made and the digital artery and vein are ligated proximally. The digital vessels are isolated from the digital nerve and dissected distally, reflecting the island flap. At this point as much soft tissue as possible around the digital artery should be included to ensure the venae comitantes are included (Eaton, 1968). The digital artery should be dissected almost to the middle of the middle phalanx (Fig. 1B) and the ability of the flap to reach the defect is checked. Once this is confirmed the tourniquet is released, and after the vascularity of the flap is confirmed the skin incision is extended to the defect in order to bury the vascular pedicle. The island flap is sutured into the 290

In March 1985 a 48-year-old male trapped the distal phalanx of his right middle finger in a machine which cut it off. Replantation was attempted immediately but failed. The patient did not want to have the finger shortened further and 6 weeks later a 1.5 cmz reverse vascular pedicle digital island flap was raised in the manner described from the ulnar side of the proximal phalanx for covering the stump (Fig. 2A-C). The flap survived perfectly (Fig. 2D). Three years after operation the transferred flap showed hypoaesthesia and the moving 2PD was 10 mm. Sweating was observed to a moderate degree. Case 4 A Sd-year-old male caught his left hand in a dust collector and he was referred to our unit a week later from an emergency hospital. The pulp skin of the distal phalanges of the index and middle fingers was almost completely lost, while in the ring finger a volar skin defect extended from the centre of the middle phalanx to the distal phalanx. and these wounds were contaminated (Fig. 3A).

291

REVERSE VASCULAR PEDICLE DIGITAL ISLAND FLAP

vascular

Flap design

A

Island flap elevated vascular pedicle B

and skin incision

full-thickness

Pulp defect C

was covered

&‘h

pedicle

a reverse

skin

by island flap

Fig. 1 Figure l-(A) Flap design and skin incision. (B) Digital vessels ligated proximally, the vascular pedicle separated nerve and an island flap elevated. (C) Full thickness skin graft to the donor defect. with tie-over dressing.

Table 1 Case No.

from the digital

Case reports

Affected Se.u Age finger

Site qf skin de&t

Size of frap (4

Donor site

Complications

Other procedures

Results

M

48

Right middle

Pulp

1.5x 1.5

Ulnar

-

Good

M

56

Left ring

Amputated stump

1.5 x 2.2

Radial

Infection Margin necrosis

Good

M

25

Right middle

Pulp

1.0x 1.5

Ulnar

Congestionremoval of some sutures

Good

4

M

58

Left index middle

Pulp Pulp

1.5 x 1.8 1.8 x 2.0

Ulnar Radial

-

Cross-finger

5

M

43

Right middle

Fingertip

1.5 x 2.2

Radial

-

Reduction fracture

6

M

58

Left middle

Pulp

1.8 x 2.2

Radial

Congestionremoval of some sutures

Good

I

M

41

Leftmiddie

Pulp

1.7 x 2.2

Radial

-

Good

flap of

Good Good Good

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Fig. 2

(B) Intraoperative photograph showing elevation of the island flap. (C) Intraoperative photograph showing pulp defect covered with island flap. (D) Postoperative view after one year. Figure 2-Case

I. (A) Pulp defect and flap design preoperatively.

An oval-shaped island flap of 1.5 x 1.8 cm was applied to the index finger from the ulnar side of the proximal phalanx and one of 1.8 x 2.0 cm was elevated from the radial side of the proximal phalanx of the middle finger. The defect in the volar skin of the ring finger was covered with a cross-finger flap from the dorsal side of the middle finger (Fig. 3B). The flaps all survived perfectly and the cross-finger flap was detached 2 weeks later. Three months after operation the patient was back at work (Fig. 3C).

Case 5 A 40-year-old male crushed his right middle and ring fingers in a paper-cutting machine. There was a fracture-

dislocation of the base of the distal phalanx of the middle finger and severe contusion. Necrosis of the dorsal skin of the fingertip occurred and an operation was performed on 17 March (Fig. 4A, B). The fracture was reduced and fixed with Kirschner wires and an oval-shaped island flap of 1.5 x 2.5 cm was elevated from the radial side of the base of the proximal phalanx and the fingertip defect covered (Fig. 4C, D). The flap survived perfectly (Fig. 4E) but 6 months after operation a slight flexion contracture of the finger was noted.

Discussion Various

procedures

have

been

attempted

for skin

Fig. 3 Figure &Case 4. (A) Preoperative view showing pulp defects of index and middle fingers, and skin defect reaching from the middle phalanx to the pulp of the ring finger. (B) Postoperative photograph after 2 weeks showing complete survival of all the flaps. On the ring finger a cross-finger flap from the dorsal side of the middle finger has been used. (C) 5 months postoperatively.

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Fig. 4 Figure 4-Case 5. (A) Preoperative view showing contusion of the fingertip. (B) Preoperative X-ray indicating the fracturedislocation of the base of the phalanx. (C) Immediately after operation. (D) Fracture of the distal phalanx treated simultaneously with K wire. (E) 5 months after operation.

defects of the pulp or amputations of the distal phalanges of fingers. For amputated stumps conservative treatment, free grafts, the TranquilliLeali (1935) method and the Kutler (1944) method using subcutaneous pedicle flaps have been used. For pulp defects thenar and cross-finger flaps have been popular. In the hand, even if the size of the skin defect is small, a local or regional flap may sometimes not be applicable because of the location of the skin defect or the state of the surrounding skin and adjacent fingers. Application of a distant flap may also be difficult because of the smallness of the skin

defect. In such cases we have been applying vascular pedicle island flaps such as the dorsal metacarpal flap. The principle of the neurovascular pedicle island flap was established by Bunnell (1952), Littler (1960) and Tubiana and Duparc (1961) and it was first used in the sensory reconstruction of the thumb. Subsequently it came to be applied to small skin defects in the hand in which cover was difficult. Rose (1983) reported in such cases the use of an island flap containing the vascular pedicle alone, with the digital nerve preserved, and Weeks and Wray (1978) described an island flap in which the

294 proximal end of the digital artery was ligated and cut and the flap transposed to cover a dorsal skin defect over the PIP joint. It was after using Rose’s island flap that we considered using a reversed vascular pedicle as described here. This method is based on the anastomoses between the radial and ulnar digital arteries (Fig. 5). The existence of this anastomosis has long been known but the number of anastomotic vessels and their configuration are not mentioned in detail in most textbooks. Yamamoto (1939) recognised a deep arcuate anastomosis at approximately the mid point of both the middle and proximal phalanges and named it the transverse anastomosis. He stated that the anastomosis across the proximal phalanx is predominant over that in the middle phalanx. Saito (1956) investigated digital artery anatomy in the Japanese and called this anastomosis a commissural branch. He reported that the small anastomosis is superficial and is also present on the dorsal side. He also said that the commissural branches occur mostly in pairs and that large branches coincide at the levels of the PIP and DIP joints. Edwards (1960) called these anastomotic branches the proximal and distal transverse digital arteries and reported that such arteries are constantly present at the level of the neck of the phalanx in contact with the phalangeal bone. Thus, although there are certain differences in the description of the anastomotic arteries, their existence is commonly stated to be constant. Recently Zbrodowski etaI. (198 1) have named these anastomotic branches the digito-palmar arch. We are now investigating the digital palmar arches by cadaver dissection. The digital palmar arch arises in the proximal twothirds of the proximal phalanx and lies half-way along the middle phalanx. It perforates the deepest part of the side of the flexor tendon sheath to lie beneath the check rein ligament of the volar plate and passes between the posterior wall of the tendon sheath and the periosteum to form the arch. By using such anastomotic branches in a case of a complete transmetacarpal amputation, Tonkin et al. (1988) succeeded in replanting all fingers by anastomosing one common digital artery alone. From these findings it appeared that sufficient blood supply should be available for the reverse vascular pedicle. In all the 7 cases and 8 fingers described here, vascularity was satisfactory. However, some sutures had to be removed in 3 cases because of flap congestion due to compression of the vascular pedicle by the overlying skin. Since there is little subcutaneous soft tissue in fingers, the

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skin is put under tension by the vascular pedicle and it is important to suture it loosely and coarsely. In order to prevent excessive traction on the vascular pedicle it must be long enough and, as in other flap operations, it is equally essential to design the flap slightly larger than the defect so that tension may not be applied to it when it is sutured. For successful reconstruction of amputated stump or pulp defects, a satisfactory sensory recovery is one of the requirements. In Case 1, 3 years after operation, the moving 2PD was 10 mm and the sensation was hypoaesthetic, but in the other cases the follow-up periods are short. Because the skin is from the volar side of the finger, favourable results are expected on long-term followup. Other advantages of this technique are its relative simplicity and the fact that the operation is confined to one operative field. However, because of the limited sensory recovery the indications of the technique are restricted at present to the middle, ring and little fingers of the non-dominant hand. The island flap should preferably be elevated from

Fig. 5 Figure S-Case palmar arches.

4. Preoperative

angiogram

showing

the digital

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the ulnar side in the middle finger and from the radial side in the ring and little fingers. This should avoid paraesthesia and numbness due to injury of the nerves when isolating the vascular pedicle, even if such injury is only temporary. References Bunnell, S. (1952). Digit transfer by neurovascular pedicle. Journal of Bone and Joint Surgery, 34A, 712. Eaton, R. G. (1968). The digital neurovascular bundle; a microanatomic study of its contents. Clinical Orthopaedics and Related Research, 61, 116. Edwards, E. A. (1960). Organization of the small arteries of the hand and digits. American Journalof Surgery, 99,831. Kojiia, T., Hayasbi, Y., Sakorai, N., Bang, H. and Tsuchida, Y. (1986). Eleven cases of vascular pedicle island flap coverage for difficult skin defects on the hand. Journal of the Japan Society for Surgery of the Hand, 3,350. Kutler, W. (1944). Method for the repair of finger amputation. Ohio State Medical Journal. 40, 126. Littler, W. (1960). Neurovascular skin island transfer in reconstructive hand surgery. Transactions of the International Society of Plastic Surgionq 2nd Congress, London 1959. Edinbureh, London: E. & S. Livinestone Ltd. D. 175. Rose, E. E. (1983). Local arterial&d island flap coverage of difficult hand defects preserving donor digit sensibility. Plastic and Reconstructive Surgery, 12,848. Saito, H. (1956). Corrosion anatomical study of the Japanese digital artery. Kaibogaku-Kyoshitsu Gyosekirhu (Jikei University School of Medicine, Tokyo), 15, 1. Tonkin, M. A., Ames, E. L., Wolii, T. W. and Larsen, R. D. (1988). Transmetacarpal amputations and replantation: the

importance of the normal vascular anatomy. Journal of Hand Surgery, 13B, 204. TranquilI&Leali, E. (1935). Riconstruzione dell’apice delle falangi ungueali mediante autoplastica volare peduncolata per scorrimento. Infort tram Luvoro, 1, 186. Tubiana, R. and Duparc, J. (1961). Restoration of sensibility in the hand by neuiovascuiar skin island transfer. Journ*> of Bone and Joint Surgery, 43B, 474. Weeks, P. M. and Wray, R. C. (1978). Management of Acute Hand Injuries. A Biological Approach. 2nd Edition. St Louis : C. V. Mosby Co. Yamamoto, H. (1939). Anatomisch-stereoskopische Rotgenuntersuchungen uber die Hand und Fingerarterien der Japaner. Kaibogaku-zassi, 14,837. Zbrudowski, A., Gajisin, S. and G&e&i, J. (198 1). The anatomy of the digitopalmar arches. Journal of Bone and Joint Surgery, 63B, 108.

The Authors Tadao Kojima, MD, Professor Yosbitaka Tsucbida, MD, Assistant Yuichi Hiras.6, MD, Instructor Toshihiko Endo, MD, Instructor

Professor

Department of Plastic and Reconstructive Surgery, University School of Medicine. 3-25-8 Nishishinbashi. ku, Tokyo 105, Japan Requests

for reprints

to Dr Kojima

The Jikei Minato-

at the above address.

Paper received 26 June 1989. Accepted 30 October 1989 after revision