Aust. N . Z . J . S U ~ R . (1995) 65, 412-416 ORIGINAL ARTICLE

V-Y ADVANCEMENT HAMSTRING MYOCUTANEOUS ISLAND FLAP REPAIR OF ISCHIAL PRESSURE ULCERS

C. COPE, P. BARRY, M. HASSALL, R. BARNETT, M. RICHARDS AND J. VANDERVORD Department of Plastic and Reconstructive Surgery, Royal North Shore Hospital, Sydney, New South Wales, Australia

Thirty-seven ischial pressure ulcers were repaired in 27 patients (eight quadriplegic, 19 paraplegic) between 1988- I993 using the V-Y advancement hamstring myocutaneous island flap. Twenty-one ulcers (57%) arose de n o w and 16 were recurrent, with five patients having bilateral ulcers. The average duration of the ulcer was 5 months (range 1-30). All ulcers extended through the deep fascia (clinical grade IV), with the average diameter being 4.7cm (range 2-10). There were four major flap complications (11%). All but one of the ulcers healed at discharge (97%). Mean follow up was 20 months (range 5-54) in 21 patients (78%), with six patients being lost to follow up. Seven of the 21 (33%) patients developed recurrent ulcers, with four of these having flap re-advancement with successful healing, and one patient having two re-advancements. Overall, 18 of the 21 (86%) patients with follow up had healed ulcers at time of follow up.

The V-Y advancement hamstring myocutaneous island flap is versatile, reliable, easy to perform, has few complications, and can be re-advanced in the event of recurrence.

Key words: major flap complications, spinal cord injury.

INTRODUCTION

The incidence of spinal cord injury in Australia is approxi- mately 20 per million population per year. Life expectancy following spinal injury is now 85% of normal, thus the number of patients in the community with spinal injury is increasing. Ischial pressure ulcers are the most common type of ulcer occurring in patients with spinal cord injury; this accounts for approximately 30% of all pressure ulcers. Treatment by simple skin closure with cutaneous flaps is ineffective in patients with spinal injury. Primary healing occurs in only 50% of patients, with 50% of those ulcers that do heal recurring within 2 years.’”

Reconstructive procedures for ischial pressure ulcers have evolved during the last 10 years, with increasing emphasis on reliability of flap design and preserving reconstructive options in case of recurrence.

This paper reports the V-Y hamstring myocutaneous island flap in the repair of ischial pressure ulcers.

METHODS

A retrospective review was undertaken of patients from the Spinal Unit of Royal North Shore Hospital, Sydney, who had undergone V-Y hamstring flap repair of ischial pressure ulcers during the period from 1988 to 1993. Clinical details of the patients’ presentation, pre-operative assessment, op- eration and postoperative course were obtained. Follow up was carried out by contact with the patients and/or their local doctor. Details obtained included any recurrence or infec- tion, as well as the incidence of temporary or minor breakdown.

Correspondence: Dr J. Vandervord, Department of Plastic Surgery, Royal North Shore Hospital, St Leonards. NSW 2065. Australia.

Accepted for publication 20 October 1994.

PRE-OPERATIVE ASSESSMENT An assessment was made of the pressure ulcer and also of the patient’s general health. This included details of whether the ulcer was recurrent, whether any previous operative repair had been undertaken, and the presence of other pressure ulcers. The pressure ulcers were graded according to the system introduced by Shea (Table and the size, presence of infection and any generalized sepsis were re- corded. Investigation of infection included bacterial swabs, white cell count and erythrocyte sedimentation rate, and plain radiographs were performed which looked for evi- dence of osteomyelitis. Assessment of the patients’ nutri- tional status included measurement of their haemoglobin and serum albumin.

Initial debridement and drainage were carried out in grossly infected ulcers, combined with intravenous anti- biotics, followed by flap repair when the ulcer was clean. Patients with severe anaemia (haemoglobin C 8 g/dL) were transfused pre-operatively.

Anatomy The long head of biceps femoris, semi-membranosus and semi-tendinosus take their origin from the ischial tuberosity.

Table 1. Grading system of pressure ulcers

Grade Definition

I Acute inflammatory reaction involving all soft tissue layers with partial thickness ulceration limited to the epidermis

Full thickness skin ulcer extending to the underlying subcutaneous fat

Necrotic, infected ulcer limited by the deep fascia but extensively involving the fat with undermining of the skin

tissue spread, osteomyelitis and septic, dislocated joints

I1

111

IV Penetration of the deep fascia with extensive soft

V-Y FLAP REPAIR FOR ISCHIAL ULCERS 413

The short head of biceps has its origin along the linea aspera of the femur, and joins with the long head above the knee with the common tendon inserting into the head of the fibula. The biceps femoris is the largest of the hamstring muscles, covers the sciatic nerve, and its tendon is related closely to the common peroneal nerve at its insertion. The semi- tendinosus and semi-membranosus insert into the medial condyle of the tibia, with the semi-membranosus lying medially in its course in the thigh. The gracilis is in the adductor compartment of the thigh and takes its origin from the inferior edge of the body and inferior ramus of the pubis, and inserts into the upper part of the medial surface of the tibia. behind sartorius and above semi-tendinosus.

Vascular anatomy All three hamstring muscles are supplied segmentally by multiple vascular pedicles that arise from the popliteal artery and from the perforating branches of the profunda femoris artery. These branches enter the posterior thigh deep to the adductor muscles. Blood supply of biceps fernoris. There are between two and five vascular pedicles supplying the biceps femoris (mean 3.6).4 The vascular pedicles, after piercing adductor magnus, travel distally for about 3 to 4cm before piercing biceps femoris. This allows proximal advancement after the muscle is freed at both its insertion and origin. There is debate over the dominant vascular pedicle supplying the long head of biceps femoris. Quaba et a/.’ found that the major vascular pedicle was within 10 to 14cm of the ischial tuberosity, supporting the findings of McCraw.6 Tobin et ul., however, found that the distal half of the muscle belly received 65% of major vascular pedicles, with major pedicles entering the distal half of the muscle in all cases.4 Curuneous blood supply. The principal blood supply of the skin of the flap is via myocutaneous perforators from the underlying biceps femoris muscle, supplemented by per- forators from the semi-membranosus and semi-tendinosus muscles. Fasciocutaneous vessels, which run along the lat- eral intermuscular septum, also contribute to the blood supply of the posterior thigh skin by anastomosing with branches of the myocutaneous perforators.’ However, these anastomotic vessels are divided while raising the flap.

The cutaneous territory of the biceps femoris alone is estimated to be 12 X 35cm.’ and this area is increased by the inclusion of semi-membranosus and semi-tendinosus in the flap. The cutaneous area of the flap may at times approximate this, especially if the pressure area is large. If the cutaneous element of the flap is extended to the popliteal skin crease it is probably a random extension of the territory supported by the dense fascial plexus. Blood supply ofgrucilis. The gracilis muscle has three to five supplying vascular pedicles along its length. The domi- nant vascular pedicle, the most proximal, is the medial femoral circumflex artery, which is a branch of the profunda femoris artery and which enters the medial one-third of the muscle approximately 10 cm inferior to the pubic tubercle.

Operative technique The patient is placed prone under general anaesthesia, and the surface markings of the flap drawn (Fig. 1). The base of the triangle (skin paddle) is the width of the ischial ulcer,

Fig. 1. The anatomy of the hamstring muscles, showing the surface markings of the flap and the area excised around the ulcer.

Sclmtk rwve

Gluteus maximus

semitindinours

Fig. 2. Transverse section through the thigh, showing the relation- ship of the hamstrings to the surrounding muscles, and the sciatic nerve.

with the sides extending down the thigh to the midline, approximately 4 cm proximal to the popliteal skin crease. The ulcer is excised en bloc with a margin of surrounding skin and subcutaneous tissue, together with the superficial part of the ischial tuberosity.

The flap incision is first made distally, continuing though the deep fascia to identify the biceps femoris, semi-membra- nosus and semi-tendinosus. Care should be taken not to undermine the skin paddle, and to ensure that the skin paddle is centred over the muscles. Traction is then placed on the muscles and they are divided sequentially, as distally as possible, using diathermy. The dissection then continues proximally, separating the hamstrings from the surrounding muscles; the semi-membranosus from gracilis and the adductor magnus medially, and laterally the long head of biceps from the short head of biceps inferiorly, and gluteus maximus superiorly (Fig. 2). In the plane deep to the ham- sting muscles is the adductor magnus, with the sciatic nerve running in fascia over this muscle. All the perforating vessels (pedicles) are preserved, but any excess fascial connective tissue, which could prevent advancement, is stripped from

414 COPE ET AL.

the vessels. The muscles are then detached from the ischial tuberosity, again by diathermy (the large anastomotic vessels present here are not necessary for flap survival). This detach- ment is an important step, as it leaves the muscles free on their vascular pedicles, allowing 8 to 10 cm of advancement. The superficial part of the ischium is excised to reduce any bony prominence.

The proximal end of the flap is inset by attaching the muscle to the fascia/periosteum above the ischium. Excess skin can be de-epithelialized if necessary, and this helps to provide tissue bulk to the area (Fig. 3). The flap is sewn using deep sutures, as well as intradermal sutures, to relieve the tension. Three suction catheters are placed; one over the ischium and the others on either side of the flap. Postoperatively, the drains remain in for 2 weeks, and the patient remains off the flap for 3 weeks, followed by gradual mobilization.

RESULTS Twenty-seven patients underwent V-Y hamstring flap repair of 37 ischial pressure ulcers during the period 1988 to 1993 (Table 2). In 21 cases (57%), it was the first presentation with the pressure ulcer, and in 16 cases the ulcers were

recurrent. Most of the patients with recurrent ulcers had only received conservative management previously, with only three patients having had previous operative repair with another type of flap. Five patients had bilateral ulcers. The average duration of the ulcer before repair was 5 months (range 1-30).

All of the ulcers extended through the deep fascia (clinical grade IV), with the average diameters being 4.7 cm (range 2-10). Twenty-nine (78%) of the ulcers were infected on admission, the two most common organisms being p- haemolytic streptococcus and Staphylococcus aur’eus.

Eleven patients (40%) had at least one other pressure ulcer at presentation, with 14 (52%) having clinical and biochemi- cal signs of malnutrition (haemoglobin < 10.0 g/dL and/or albumin < 35 mg/dL).

Seven ulcers were debrided pre-operatively, and one ulcer, which presented as an abscess, was drained 2 weeks before repair. Six patients underwent pre-operative trans- fusion for severe anaemia (haemoglobin < 8 g/dL).

Operative repair of the ulcers was performed as described previously (Fig. 4). In two cases the large size of the defect following excision of the ulcer necessitated the inclusion of gracilis, as well as the hamstrings, in order to fill the defect. Twelve patients required either intra- or postoperative blood transfusion, with the average requirement being 2 units.

De-epitheliatized areas Complications

Postoperatively, two flaps had necrosis of the proximal end (Table 3). In one patient the flap was re-advanced 2 weeks postoperatively which healed well initially, but recurred at 12 months, and underwent a second re-advancement. The other flap was infected persistently, and required debride- ment 5 weeks postoperatively, at which time the proximal

Fig. 3. The completed flap, showing the attachment of the muscle above the ischial tuberosity and the de-epithelialized portion of the flap.

Table 2. Clinical details of 37 ischial pressure ulcers

First presentation 21

Previous operative repair 3

Recurrent ulcer 16 Bilateral 5

Average diameter (cm) Clinical Grade IV Infected

Other pressure ulcers Malnutrition

4.7 37 29

1 1 14

&-operative debridement 8

- r .I”_

Fig. 4. Bilateral V-Y advancement hamstring flaps, showing good healing 1 month after advancement of the second-flap.

V-Y FLAP REPAIR FOR ISCHIAL ULCERS 41s

Table 3. Postoperative complications

Immediate Flap necrosis (partial) Haematoma Infection Superficial breakdown (healed spontaneously)

Recurrent ulcers Readvancement Unhealed

Late

Superficial breakdown (healed spontaneously)

muscle was noted to be necrotic. This flap was re-advanced subsequently, but had further infection and recurrence.

Two patients developed haematomas which became in- fected and required drainage. In both of these patients the suction drains at the site of haematoma had become blocked, which emphasized the need for careful observation to ensure patency of the drains. One patient developed a minor wound infection which responded to intravenous antibiotics, while two developed areas of superficial breakdown after com- mencing weight-bearing, but which healed spontaneously.

All but one of the pressure ulcers were healed at discharge (97%).

Follow up The mean follow up was 20 months (range 5-54) in 21 patients (78%), with six patients being lost to follow up. Overall seven of the 21 patients (33%) have developed recurrent pressure ulcers.

Four patients have had successful re-advancement of the flaps. These patients presented at an average of 10 months after their initial repair (range 6- 12). In one of these patients the flap has been readvanced twice, with good healing. These patients have had no further problems with a mean follow up of 1 1 months (range 3-31).

Three other patients have had recurrence; the patient discussed above with continuing flap infection and necrosis, one patient with a sacral chordoma with recurrence at 7 months which has required further debridement, and one patient who removed the drains and discharged himself 12 days after flap repair (this patient has refused further treat- ment). These patients have unhealed pressure ulcers. In addition, three patients had recurrent minor breakdowns which heal with short periods of bed rest.

Overall 18 of the 21 (86%) patients with follow up have healed ulcers at time of follow up.

DISCUSSION The treatment of ischial pressure ulcers in paraplegics re- mains a continuing problem. Prevention is much more effective than cure, and an effort must be made to identify and change the factors contributing to the formation of the ulcer. Some of these factors, such as environmental (e,g. the type of cushion used when sitting in a chair), are relatively easy to change. However, there are often other factors such as patient attitudes, personality and lifestyle which are much more difficult to address.

If these efforts fail and surgical treatment is needed in

order to minimize recurrence, it is necessary to have muscle as well as skin cover when reconstructing the defect left after excision of the ulcer.

Simple skin closure with cutaneous flaps results in pri- mary healing in only 50% of patients, with 50% of the ulcers that heal recurring within 2 years. ' .3 Random cutaneous flaps, such as the posterior thigh flap, are vulnerable to partial necrosis because of the loss of myocutaneous perfor- ators (the most important source of cutaneous blood supply). They also provide little bulk for padding, with these two factors resulting in the high incidence of recurrence.

The biceps femoris muscle was used initially as a trans- position flap to improve the amount of tissue available to till the defect and provide bulk,3 but this flap suffered from a tendency to partial necrosis because of division of the distal pedicle( s) to enable transposition.

Tobin ef crl. introduced the idea of using the biceps femoris myocutaneous flap as an advancement rather than a transposition flap, thus providing bulk and maintaining the integrity of the myocutaneous perforators.' Hurteau ef ul. modified this further by including the semi-membranosus and semi-tendinosus muscles, and using a triangular island of overlying skin as a myocutaneous V-Y advancement flap,* and Kroll and Hamilton extended the flap inferiorly, thus enlarging it.'

The V-Y advancement hamstring myocutaneous island flap has a number of advantages. First, it has great reliability and durability as a result of the preservation of all the vascular pedicles and the myocutaneous circulation, thus maximizing the blood supply in the flap. In this study there were only two cases of flap necrosis in 37 flaps, both of these being limited to the proximal tip of the flap. This low incidence of flap necrosis is also borne out by Furthermore, the dissection of the flap is technically easy once the anatomy is understood.

Second, the flap provides a large bulk in paraplegics, whose muscles are often severely atrophied, to both fill and cover the defect following excision of the ulcer. The bulk is supplied by the muscles themselves, supplemented by the de-epithelialized portion of the proximal flap. This means that the ischial tuberosity is well padded and thus minimizes recurrence. In very large ulcers it is also possible to include the gracilis muscle in the flap to provide further bulk. This was done in two patients in this series.

Third, using this flap retains the maximum reconstructive options for future treatment. It does not interfere with subsequent use of adjacent flaps (e.g. tensor fascia lata, gracilis, or gluteus maximus), allowing these to be used for trochanteric and sacral reconstruction.

Fourth, the large size of the flap, and removal of all attachments of the hamstrings except the vascular pedicles, allows the flap to be re-advanced several times if required. This is especially important in view of the high recurrence rate reported in this and other series.*.'.'('

In this series, 97% of the ulcers were healed at discharge, but 33% had recurred after a mean follow up of 20 months. Four patients had re-advancement of the flaps for recurrent ulcers (one patient underwent two re-advancements), and in these patients the flaps have healed well. Overall 18 of the 21 (86%) patients with follow up have healed ulcers.

In summary, the V-Y advancement hamstring myocuta- neous island flap is a versatile, reliable flap which is techni-

416 COPE ET AL.

cally easy to perform and has few complications. It can also be re-advanced if necessary in the event of ulcer recurrence. We believe that this flap is a useful method for the recon- struction of ischial pressure ulcers.

REFERENCES Dansereau JG, Conway H. Closure of decubiti in paraplegics. Report on 2000 cases. Plast. Reconstr. Surg. 1964; 33:474. Conway H, Griffith BH. Plastic surgery for closure of decubi- tus ulcers in patients with paraplegia. Am. J . Surg. 1956; 91: 946. Shea JD. Pressure sores. Classification and management. Clin. Orthop. 1975; 112: 89. Tobin GR, Sanders BP, Man D. Weiner LJ. The biceps femoris myocutaneous advancement flap: a useful modification for ischial pressure ulcer reconstruction. Ann. P last. Surg. 1981; 6: 396-40 1.

5 . Quaba AA. Chapman R, Hackett MEJ. Extended application of the biceps femoris musculocutaneous flap. Plast. Reconstr.

6. McCraw JB. Dibbell DG, Carraway JH. Clinical definition of independent myocutaneous vascular territories. P lust. Re- constr. Surg. 1977; 60: 34 I .

7. Cormack GC, Lamberty BGH. The blood supply of thigh skin. Plast. Reconstr. Surg. 1985; 75: 342-54.

8. Hurteau JE, Bostwick J, Nahai F. et al. V-Y advancement of hamstring musculocutaneous flap for coverage of ischial pres- sure sores. Plast. Reconstr. Surg. I98 I ; 68: 539.

9. Kroll SS, Hamilton S. Multiple and repetitive uses of the extended hamstring V-Y myocutaneous flap. Plast. Reconstr. Surg. 1989; 84: 296.

10. Disa JJ. Carlton JM, Goldberg NH. Efficacy of operative cure in pressure sore patients. Plast. Reconstr. Surg. 1992; 89: 272.

Surg. 1988; 81: 94-105.