KEY WORDS
Finger defect - groin flap - hand defect - high-tension electric burn - lumbo-umbilical
flap - paraumbilical perforators
INTRODUCTION
Electrical burns form 3%–5% of burn admissions and extremities are involved in more
than 70% of cases.[1]
[2] Young men are mostly involved while on work at power lines.[3]
[4] It leads to tissue necrosis of skin and damage along its path through the muscles,
vessels, nerves and bone.[5] Severe injury can occur, especially in limbs.[6] Cover of vital structures (tendons, nerves, vessels and bone) is needed to preserve
or achieve a better functional result.[7] Limb salvage and reconstruction in these cases can be extremely difficult.[8]
The local tissue is usually not available or is insufficient in severe cases, necessitating
import of tissue from a distant source.[1] Every attempt is made to preserve and repair fingers which show promise of survival.[7] Flap cover is urgent to save vital structures. The use of flap improves functional
and esthetic results and prevents amputations.[9]
[10]
Microvascular free flap reconstruction in electrical injury is quite challenging if
there is accompanying vascular injury.[1] Electrical damage to vascular endothelium manifests over a period of time.[11] This often precludes the use of free tissue transfer, especially in fingers.
Distant pedicled flaps (groin, tensor fascia lata, superficial external pudendal artery
and ipsilateral abdominal flaps) have been used in hand reconstructions[12]
[13]
[14]
[15] but there is a lack of literature when it comes exclusively to volar hand and finger
coverage in high-tension electrical burns. The above-mentioned flaps for volar hand
and fingers are difficult to inset and keep upper limb in a very uncomfortable position.
We describe our experience with a versatile contralateral lumbo-umbilical flap with
a relatively narrow pedicle base on the paraumbilical perforators. In all our cases,
we used the contralateral lumbo-umbilical flap to cover the volar aspect of fingers
and hand.
MATERIALS AND METHODS
The prospective study was conducted from October 2013 to April 2016 we received thirty-eight
patients of high-tension electric burn. Of them, eight had predominantly deep burns
on volar aspect of hand and fingers [Table 1]. In emergency care reliable vascular access was established, patients catheterised,
cardiac monitoring was done and advanced trauma life support algorithm was followed
in all patients. Patients with serious accompanying trauma were not included in the
study group. Further evaluation and interventions were performed as required (fluid
resuscitation, escharotomy/fasciotomies) on the day of admission. Patients were taken
up for debridement and planned for lumbo-umbilical flap cover in the 1st week of injury for salvage of hand and finger function. Paraumbilical perforators
were confirmed by a hand held Doppler on the contralateral side to that of the involved
hand. The direction of the flap was inferolateral, extending to the lumbar region
up to posterior axillary line [Figure 1]. The flap base is centred on one of the perforators. The flap was raised superficial
to the fascia of the external oblique muscle. At the flap base, perforators were not
visualised to avoid trauma. Wide undermining and advancement of donor site edges were
performed for a tension-free closure. Donor site was closed in two layers. The flaps
were easily inset on the fingers, and syndactylisation was done if more than one finger
was involved. The flaps were detached between 3 and 4 weeks after inset. After pedicle
separation, the pedicle of the flap was carefully inset, avoiding distortion of the
paraumbilical region. Primary tendon reconstruction was not performed at the time
of flap inset. The patients were closely observed for first 6 weeks for any flap or
donor site complications and then followed monthly to assess donor and recipient site
characteristics for 6 months to 2 years.
Figure 1: Lumbo-umbilical flap direction and extension limit shown up to posterior axillary
line
Table 1
Brief profile of cases
|
Sex
|
Age
|
Soft tissue defect (volar hand)
|
Size of the lumbo-umbilical flap
|
|
Male
|
24
|
Right middle, ring and little finger
|
15 cm×8 cm
|
|
Male
|
15
|
Left middle finger
|
12 cm×5 cm
|
|
Male
|
38
|
Right middle and ring finger
|
13 cm×7 cm
|
|
Male
|
26
|
Right index, middle and ring finger
|
16 cm×8 cm
|
|
Male
|
30
|
Right middle and ring finger
|
15 cm×8 cm
|
|
Male
|
35
|
Right middle and ring finger
|
15 cm×7 cm
|
|
Male
|
21
|
Right index and middle finger
|
12 cm×7 cm
|
|
Male
|
23
|
Left ring and middle finger
|
15 cm×8 cm
|
Three index cases are discussed as under:
Case 1
A 26-year-old man with high-tension electric burn involving right upper limb as an
entry point and right thigh as the exit was admitted in an emergency. The hand burn
mainly involved volar aspect of fingers and palm. After resuscitation and stabilisation,
the patient was taken electively to operation theatre, and debridement of devitalised
tissues was done. After debridement, tendon/bone of index, middle and ring fingers
got exposed. Distal vascularity was intact. The umbilical perforators on contralateral
side of abdomen were identified, and lumbo-umbilical flap (8 cm × 16 cm) was raised.
The injured fingers were syndactylised and covered with a flap. The detachment was
done after 3 weeks without any delay. Final inset was given, and at this time palm
of the hand was grafted. The flap survived completely. Some pus discharge from under
the flap in post-operative period was managed by local care. Donor site scar was visible
but acceptable to the patient [Figure 2a-e].
Figure 2: (a) Severe electrical burn injury right hand. (b) Tissue loss over index, middle
and ring fingers with exposed tendon/bone after debridement. (c) A 8 cm × 16 cm contralateral
lumbo-umbilical perforator pedicled flap was planned for cover. (d) Volar defect of
fingers was covered with contralateral lumbo-umbilical perforator pedicled flap in
a comfortable position. (e) Well-settled flap after 2 months with conspicuous abdominal
scar
Case 2
A 35-year-old male with high-tension electric burn involving the right hand was admitted
to the emergency department. The volar aspect of fingers had deep injuries. Debridement
of eschar resulted in the exposure of tendons/bone in two fingers with intact vascularity.
The lumbo-umbilical flap (7 cm × 15 cm) from contralateral side was used to cover
exposed tendon/bone of volar aspect of fingers. The inset was easy, and the carrier
segment was lengthy. Donor site was closed without tension. The patient was discharged
after 5 days from the hospital as the patient was mobile and had very comfortable
arm position. The patient was readmitted after 3 weeks and final flap inset done without
any delay. The flap survived completely without any complications. Donor site scar
was conspicuous but quite acceptable to the patient [Figure 3a-e].
Figure 3: (a) Deep electric burn right middle and ring finger. (b) A 7 cm × 15 cm contralateral
lumbo-umbilical perforator pedicled flap was planned for cover. (c) Showing post-operative
picture after detachment and inset of flap. (d) Results, hand and abdominal scar after
18 months. (e) Post-flap thinning on fingers
Case 3
A 15-year-old boy was admitted to emergency service with severe high-tension burn
injury involving the left hand. The volar aspect of thumb, index and middle fingers
were more severely involved. After stabilisation, the patient was taken for debridement
leading to tendon exposure on volar aspect of middle finger necessitating a flap cover.
A 5 cm × 12 cm pedicled flap based on paraumbilical perforators was planned. The whole
exposed volar aspect of middle finger was reconstructed with lumbo-umbilical flap
of contralateral side. The thumb and index finger were skin grafted. The donor site
was closed primarily. The flap was detached after 3 weeks without any delay and final
inset given. The flap survived completely without any complication [Figure 4a-c].
Figure 4: (a) Severe electrical burn injury left hand. (b) Showing soft tissue loss over thumb,
index and middle finger with exposed tendon of middle finger. (c) The result after
12 months
RESULTS
Eight contralateral lumbo-umbilical flaps were used for volar finger reconstruction
in eight patients. All patients were young males between 15 and 38 years of age, with
a mean age of 26.5 years. Large flaps up to 8 cm × 16 cm were raised. Seven flaps
survived completely, and one had necrosis of distal part requiring readvancement after
debridement. All patients were mobilised within 48 h and five were discharged within
a week. There was no dehiscence of inset in any case. None of the patients complained
about the positioning of the arm and hand. Pedicle division was done between 3 and
4 weeks after inset. Infection occurred in three out of eight cases and was managed
by local care. The donor site was primarily closed in all cases. Donor site scar was
conspicuous but not bothersome.
DISCUSSION
Various pedicled abdominal flaps have been described for coverage of hand defects.[8] These flaps may be random or axial based on the dominant paraumbilical perforators
originating from the deep inferior epigastric artery. Other axial abdominal flaps
such as the groin flap and superficial inferior epigastric artery (SIEA) flap are
also used. The groin flap is the workhorse for reconstruction of dorsal hand defects.[16]
[17] Its inset on volar aspect, especially fingers, is quite difficult and the position
of extended shoulder with supinated forearm and hand on ipsilateral side makes it
very uncomfortable for the patient.[18] The SIEA flap described by Shaw and Payne can easily cover dorsal finger defects,
but its use for volar fingers is again difficult.[19] The contralateral pedicled lumbo-umbilical flap keeps shoulder adducted; forearm
flexed at 90°–110° in midprone position and hand in neutral position [Figure 5]. This position is very comfortable for the patient with no tendency on the part
of patient to change it as occurs in ipsilateral flaps. Change in position does lead
to complications as edema of flap and/or dehiscence. The flap has a better physiologic
position, which is comfortable for the patient, and early mobilisation of upper limb
joints is possible with the use of this flap. There is no restriction of hip movements
leading to excellent mobility with no need to restrict the patient to the bed. There
is no violation of patient privacy as the groin region is not left exposed and the
patient can wear his/her routine clothes.
Figure 5: Comfortable position of upper limb when contralateral lumbo-umbilical abdominal flap
is used
We could easily mobilise the patients within 48 h as there was no restriction on lower
limbs. Five of our patients were discharged within a week after initial inset because
of this. They were managed on outpatient basis till readmission 2–3 weeks later. Other
advantage of this position is the ease of insetting flap on volar aspect of fingers
as compared to ipsilateral flaps. The end result is a complete tension-free inset.
The vascular anatomy of the paraumbilical region is well known.[20] In a recent microdissection study, El-Mrakby and Milner investigated the course
of paraumbilical perforator vessels.[21] A number of free flaps have been designed based on these paraumbilical perforator
vessels.[22] Yilmaz et al. first described a paraumbilical-based pedicled abdominal flap for coverage of extensive
soft tissue defects of the forearm and hand using narrower pedicle and incorporating
at least one perforator vessel. They reported total flap survival in all cases, pointing
toward the reliability of this flap.[15] A very large paraumbilical perforator-based flap for scrotal reconstruction has
been described by Kim et al.[23] Pre-expanded paraumbilical perforator flaps have also been devised as an effective
option for upper extremity reconstruction.[24] In our series, all flaps except one survived completely. The paraumbilical perforator-pedicled
abdominal flap has many advantages over other abdominal flaps. It is possible to design
a large flap extending up to the lumbar region without compromising the flap survival.
In our series of high-tension electric burn wounds, we were successful in salvaging
hand and digit function with this versatile flap in all the eight patients. The largest
flap we used was 8 cm × 16 cm and the donor site was closed primarily in all cases.
The case which showed distal necrosis had significant perforaters in the lumbar region
while elevating it. In this, possibly paraumbilical perforaters were not well developed.
This may be explained by the law of equilibrium that vessels obey.[25] Thus, we infer, that if perforators in lumbar region are of significant calibre
it may be prudent to delay the flap before complete elevation and transfer as is done
for deltopectoral flap.[26]
A visible scar has been mentioned as the main disadvantage of abdominal flap[15] although most of our patients were satisfied with the procedure. A linear scar on
the abdomen is easily accepted by the patients as the abdomen remains covered all
the time in our society. Flap debulking was needed (maximum of two procedures) though
our patients were lean and thin. All the donor sites were closed primarily.
We did not find any report in literature encouraging the use of contralateral lumbo-umbilical
flaps for coverage of volar aspect of fingers in patients with high-tension electrical
burns. The main purpose of our study is to emphasise that contralateral side of abdomen
is a viable choice for coverage for volar fingers, and its use in volar hand defects
is highly recommended.
CONCLUSION
Choosing the contralateral side gives a better physiologic position to the hand and
patients can be mobilised very early and in a very comfortable manner. Large flaps
can be elevated with primary donor site closure. Inset of the flap is easier for surgeon.
The flap fares quite well as compared to the commonly used abdominal and groin flaps
for soft tissue reconstruction of volar aspect of fingers.
Financial support and sponsorship
Nil.
