Keywords
propeller flap - local flap - perforator flap - biogeometry - post-burn reconstruction
- head and neck flaps - extremity flaps
Introduction
The reconstruction of a tissue defect with local flaps is always difficult for the
reconstructive surgeon. As anatomical and physiological understanding of tissue vascularity
is evolving, innovative local flap designs such as “propeller flaps” are possible.
The propeller flap is a local islanded flap, designed like a propeller blade with
two blades of unequal length and the nourishing vascular pedicle forming the pivot
point.[1] When the blades are switched, one arm comfortably covers the defect, and the other
covers the donor defect partially or completely. The potential of this flap to rotate
up to 180 degrees with the ability to recruit tissues from adjoining non-traumatized
areas makes this an extremely versatile flap for a variety of reconstructions.[1]
[2]
[3] Propeller flap is the iteration of flap design that began with random pattern flaps.
Because of its fairly recent inclusion in the armamentarium of reconstructive surgeons,
certain mistrust has overshadowed the safety of propeller flaps in clinical practice.
This study aims to describe the evolution, key principles, and biogeometry, operative
technique, and clinical applications of the propeller flap.
History and Evolution
Katsaros first introduced the concept of propeller flaps in 1982. He used an islanded
tensor fascia lata flap propelled through 180 degrees to cover a chest wall defect.[4] Hyakusoku et al in 1991[5] used a random subcutaneous pedicle as a pivot with two lobes and published the propeller
flap method in the British Journal of Plastic Surgery.[6] Later, further modifications such as the multilobed propeller flap and the pinwheel
flap were introduced.[7]
[8]
[9] Hallock used the term “propeller flap” to define a fasciocutaneous flap based on
a skeletonized perforator vessel and rotated by 180 degrees. This gave rise to the
concept of perforator propeller flaps.[10] Teo greatly contributed to the definition, surgical technique, and application of
perforator propeller flaps. Ever since their introduction, propeller flaps have been
modified, re-designed, and their clinical applications are still evolving.[11]
[12]
[13]
Nomenclature and Terminologies
Nomenclature and Terminologies
The Advisory Panel of the First Tokyo Meeting on Perforators and Propeller Flaps 2009
reached a terminology consensus on propeller flaps.[14]
A propeller flap is defined as an “island flap that reaches the recipient site through
an axial rotation.” The axial rotation differentiates it from other pedicled flaps.
While categorizing it as a propeller flap, three components are considered: type of
nourishing pedicle, degree of skin island rotation, and artery of origin of perforator
vessel/cluster of perforators. However, if the source vessel is not confirmed (as
in free-style design), then the anatomical region or underlying muscle is specified[14]
[15] ([Table 1]).
Table 1
Classification and nomenclature of Propeller Flaps
|
Basis of classification
|
|
|
|
|
Type of pedicle
|
Perforator pedicled propeller flaps (PPP)
|
Skeletonised perforator act as a pivot point.
Axial rotation of 180° is possible.
It is the most commonly used propeller flap.
Example – Peroneal artery perforator 180° propeller flap.
|
|
Non-perforator pedicled propeller flaps
|
Subcutaneous-pedicled propeller flaps (SPP flaps)
|
Cluster of small perforators in underlying subcutaneous tissue act as the pivot point.
Perforators are not skeletonised.
Safe rotation of flap is up to 90°.
Example – SPP flaps for post burn contractures.
|
|
Vascular-pedicled propeller flaps (VPP flaps) or axial propeller flap
|
Pivot point for rotation is the base of axial vascular pedicle and not on a perforator
itself. It is also known as an axial propeller flap. Safe rotation of reliable large
skin paddle up to 180° is possible.
Examples - Radial artery based flap, Facial artery based flap, Supratrochlear artery
based flap, Lingual artery based flap.
|
|
Position of pedicle
|
Central axis propeller flap
|
Location of nourishing pedicle is at the centre.
Central location of pedicle imparts homogeneous blood supply to skin paddle, thus
enhancing reliability of flap.
Mainly indicated for coverage of two adjacent defects.
|
|
Acentric axis propeller flap
|
Pivot point for rotation arc of the flap is at its periphery.
These flaps are very useful to cover defects, located in areas distant from regions
rich in perforators.
|
|
Modification of propeller flap
|
Composite propeller Flap
|
When the skin island of flap contains more than one single tissue such as tendon,
nerve or underlying cartilage and is propelled in defect through 180° rotation for
functional reconstruction, it is considered as a composite propeller flap
|
|
Supercharged propeller flap
|
The supercharged propeller flap is a modification of the perforator pedicled propeller
flap.An extra pedicle can be introduced by supercharging if a lengthy propeller flap
is required.
|
|
Multi-lobed propeller flap
|
Flaps with multiple lobes with axial rotation.
|
Preoperative Considerations
Preoperative Considerations
Preoperative clinical examination and doppler studies give us fair guidelines regarding
appropriate patient selection for executing a propeller flap. Potential risk factors
such as tobacco consumption in any form, systemic diseases such as diabetes mellitus
(DM), collagen vascular disease or peripheral vascular disease (PVD), should be noted.
The opinion is divided on the impact of these factors on the complication rate. Innocenti
et al[3] found no significant association between complications and these comorbidities in
their study of lower extremity propeller flaps. They also did not identify any significant
risk factors pertaining to defects, flap size, or arc of rotation.[3] However, Quaba et al[16] and Jakubietz et al[17] reported that obvious contraindications for local perforator flaps are patients
with PVD and/or insulin-dependent DM. In our experience, if there is a good perforator
intraoperatively along with a good Doppler signal, the comorbidities do not have high
risks of complications.[18]
[19] However, multicenter studies with large sample sizes will be necessary to determine
which patients and comorbidities are at higher risk of complications.
The location of the defect and its reconstructive requirements should be considered.
The area surrounding the defect should be examined for any signs of inflammation,
scars, or irradiation. Propeller flaps are to be avoided in the presence of subdermal
and suprafascial plexus injuries to the surrounding tissues.
Preoperative identification of the perforator with handheld Doppler (8–10 MHz) is
desirable. In the upper extremity, the deep vessels become superficial distally, and
Doppler specificity decreases. However, success in detecting good perforators increases
with an operator's experience.[20]
[21] Various methods described for the identification of perforators such as duplex ultrasound,
color Doppler, arteriography, magnetic resonance angiography, and high-resolution
computed tomography are more sensitive and can provide additional information. In
our experience, the handheld Doppler probe is easy, simple, cost-effective, and adequate
for the identification of perforators and satisfactorily correlates with the intraoperative
“good” perforator.”
Flap Biogeometry, Physiology, and Planning
Flap Biogeometry, Physiology, and Planning
Propeller flaps are generally raised as long and narrow flaps and are not limited
by the rules of length-to-width ratios. The perforator is eccentrically placed, and
these flaps are to be considered as two flaps on either side of the perforator, and
not as a single flap. For example, if we have a flap of width “x” and length “5x,”
and we have an eccentrically located perforator entering the flap at a distance of
“3x,” we essentially have two flaps with ratios of 1:2 and 1:3[2]
[22] ([Fig. 1]).
Fig. 1 Propeller flap biogeometry.
When we consider flap physiology, the available literature on the vascular territories
supplied by a single perforator is based on cadaver and injection studies.[3]
[23]
[24] Intraoperatively, there are a lot of dynamic changes that occur after the ligation
of extra perforators. There is an opening of adjacent potential vascular territories
that assures an optimal blood supply to the flap by recruiting cutaneous territory
beyond the anatomic territory of an individual perforator.[3] It is easy to understand that the larger the perforator dimensions, the higher the
perfusion pressure, and the higher its potential to recruit adjacent perforasome territories.[13]
[25] These changes are in addition to systemic factors and extrinsic factors such as
operation theater temperature and hypothermia, among other things. Therefore, the
answer to how much flap can be safely harvested on a single perforator in a clinical
setting still eludes us, and can be known only after the flap harvest is complete
and the tourniquet is released.[22]
[26]
[27]
[28]
[29]
Flap design: The flap planning and surgical technique have been fairly well established
with minor variations from various authors.[2]
[7]
[29]
[30]
[31]
[32]
[33]
[34] We identify the most favorable perforator with a handheld Doppler. To mark the length
of the flap, the distance from the perforator to the distal edge of the defect is
noted. Around 1 to 2 cm is added to it, depending on the thickness of the tissues,
to mark the proximal edge of the flap. It should permit comfortable reach of the flap
into the defect without any tension when axially rotated. Freestyling of the design
is considered depending on the requirements of the defect. The width of the flap is
planned in accordance with the width of the defect when a 180-degree rotation of the
flap is anticipated. It is important that the perforator, when it enters the flap,
is equidistant from the lateral edges of the flap so that there is no excessive sideways
traction on the perforator during closure. The design of the flap is always confirmed
and altered if necessary, after intraoperative identification of the suitable perforator.
Surgical Steps and Technical Considerations
Surgical Steps and Technical Considerations
Propeller flap harvest must be done under adequate exposure and illumination with
appropriate magnification. The exploratory incision is generally parallel to the long
axis of the vessel on whose perforators the propeller flap is being planned. Exploratory
incisions should be liberal to identify multiple perforators in the area of interest.
It is fashioned in a manner so that if suitable perforators are not identified, it
can be used to gain access to the underlying vessel for micro-anastomosis or the same
incision can be used to design some local flap. It is desirable to avoid damage to
the cutaneous nerves during the exploratory incision. For the lower limb, incisions
must avoid transgression over the subcutaneous border of the tibia and the tendoachilles
region[12]
[13]
[22] ([Video 1]).
Video 1 Technique of harvest of lower limb propeller flap on perforators of posterior tibial
artery.
For extremity harvest of propeller flaps, a partially exsanguinated limb gives the
advantage of easy identification of the perforator and its venae comitantes.[12]
The approach to the perforator can be either subfascial or suprafascial. The authors
prefer the subfascial approach because it is very convenient to identify the perforator.
In the suprafascial approach, the dissection is a bit tedious, but as there is no
breach of fascia, the donor site morbidity is less conspicuous.[20]
[22]
[28]
[35]
[36]
[37]
Assessment of the Perforator
More often than not, after handling and dissection of the perforator, the perforator
goes into spasm. Therefore, the first sighting of the perforator is the best opportunity
to assess the suitability of the perforator.
The good quality perforator should be of adequate caliber and associated with two
venae comitantes to sustain the vascularity of the flap. Two venae comitantes are
necessary because once the flap is axially rotated through 180 degrees, one of the
veins gets kinked because of the twist, and the other one opens up. The surrounding
fascia and the tissues must be non-contused and free of the zone of trauma.
The perforator must be assessed in terms of proximity to the defect. A perforator
that is too near to the defect might be encased in scar tissue or granulation tissue
and can be fragile. These perforators lack thromboresistant properties and are more
likely to go into spasm even with a minimal amount of dissection.[38]
[39] Perforators that are far away from the defect make the flap unnecessarily long and
risky. Thus, the appropriate perforator must be selected accordingly. The course and
orientation of the perforator into the flap must be assessed. The intraflap axiality
of the perforator must be along the long axis of the flap.
Technical tip: We should be ready to change our plan intraoperatively if a suitable
perforator is not found in the exploratory incision and near the defect.
The pulsatility of the perforator is another important criterion to be assessed. However,
because the flap is being dissected under a tourniquet, it is not possible to assess
the pulsatility at this point of time. It must be assessed at the end of the dissection
after the tourniquet is released. The beauty of propeller flaps is that we are not
concerned with the underlying anatomical variations. If we have a good quality perforator,
we can base our flap on it, irrespective of its source vessel.
Once the best perforator is identified intraoperatively, we commit to the flap design.
It is generally accepted that the longer the pedicle, the wider is the safe arc of
rotation.[3]
[36]
[40] Wong et al [29]
[41] reported that for better survival of the propeller flap, the perforator should be
at least 1 mm in diameter and should be dissected for a length of at least 3 cm. However,
excessive dissection to get a longer pedicle also increases the chance of traction
injury and perforator going into spasm. In our experience, we feel that a perforator
length of 1 to 1.5 cm is adequate, and one does not need to dissect the perforator
to the source vessel. There is often a layer of loose connective tissue surrounding
the perforator, and this layer can be easily freed from the surrounding tissue by
blunt dissection.[42]
The perforator dissection is performed meticulously in a non-traumatic fashion, with
constant irrigation with lignocaine or papaverine solution to minimize the spasm.
Particular attention must be paid to the fibrous strands around the venae comitantes,
because the low-pressure venae comitantes are most susceptible to extrinsic compression.[12]
Bipolar cautery is used judiciously for absolute hemostasis. Excessive traction on
the tiny perforator by an untrained assistant can lead to irreversible injury to the
perforator and must be avoided at all costs.
Technical tip: Perforator can be gently dissected by traction and counter traction
of the surrounding tissues, which minimizes the handling and thereby spasm of the
perforator ([Video 1]). As a general rule, all perforators that will not be used to axially rotate the
flap must be transected away from the fascia. This can be of help if the need for
supercharging arises. By the time the flap harvest is complete, the perforator has
almost always gone into spasm. It is imperative that the spasm is relieved by irrigation
with lignocaine/papaverine to produce vasorelaxation of the perforator.
Technical tip: While taking intraoperative photographs, due care must be taken that
the weight of the flap does not drag on the perforator and cause injury ([Fig. 2]).
Fig. 2 Intraoperative photography tips.
Anesthesia alters the normal thermoregulatory mechanisms. If needed, to prevent hypothermia
and subsequent spasm of the tiny perforators, the temperature of the operating theater
should be raised. Warming blankets can be used, with intravenous fluids warmed prior
to administration.[43]
Once the flap harvest is complete, the tourniquet is released, and the flap is permitted
to perfuse. Once the flap is perfused adequately for a period of 10 to 12 minutes,
it is axially rotated into the defect.
Technical tip: The flap should not be axially rotated into the defect unless there
is complete vasorelaxation and the perforator starts to pulsate.
The flap is rotated from the side, where minimal rotation is required. If flap rotation
of 180 degrees is required, the flap is rotated from both directions, and the side
which causes optimal and comfortable placement of the venae comitantes with favorable
perfusion is finalised.[12]
[30]
Technical tip: It is always prudent to note the direction of rotation in the operative
notes in case postoperative derotation is required.
The first few sutures for closure are placed along the sides of the flap near the
perforator entry point. This prevents traction on the perforator while suturing the
rest of the flap.
It is advisable to take a few crucial sutures over the donor site before the tourniquet
is released. After the tourniquet is released, edema sets in, and linear closure of
the donor site becomes difficult.
Avoiding Complications in Postoperative Period
Avoiding Complications in Postoperative Period
It is important to avoid tight circumferential bandaging proximal to, or over the
flap. Window dressing to ensure visibility of the entire flap is important. Full exposure
of the flap ensures early detection of marginal discoloration or underlying hematoma.
Postoperatively, all our flaps are monitored by experienced staff. We do not have
experience with sophisticated flap monitoring devices; however, we believe that clinical
observation with occasional needle scratches and Doppler monitoring are reliable methods
of postoperative monitoring. For propeller flaps, the most common postoperative problem
is venous congestion because of torsion-prone thin-walled veins. In the postoperative
period, all propeller flaps have a tendency for minimal congestion, which gradually
relieves over time as the veins adapt to torsional changes and flow is stabilized.
It is important to differentiate between transient congestion and true venous insufficiency.
True venous insufficiency must be promptly identified and managed to avoid compromise
of the flap. If the color changes of venous congestion are limited to the terminal
portion of the flap, its evolution and advancement are noted in the case of true venous
insufficiency. If the entire flap appears to be minimally congested, as is almost
always seen, it is prudent to observe the flap patiently for a few minutes. The increasing
darkness of the color of blood and the increased briskness of the bleeding on pinprick
are pointers to true advancing venous insufficiency. In such cases, venous supercharging
or temporary derotation of the flap can be considered. Leeches have also been used
with limited success in propeller flaps.[44]
Chen et al. demonstrated good outcomes with temporary derotation of a congested flap
along with de-epithelization of skin and debulking of fat. It decreases metabolic
demand on the vasculature.[45]
Arterial insufficiency is rarely encountered in propeller flaps. If the flap remains
pale in the postoperative period, it is almost always due to spasm of the perforator.
All maneuvers to relieve the spasm are helpful in most cases. If the flap continues
to remain pale, it can be derotated to its original position for a few days before
rotating it again.[46]
[47]
[48]
Total flap necrosis is very rare. Partial flap necrosis is fairly common and is often
limited to the skin.[46] Aggressive debridement is to be avoided, and even flaps that appear to be mottled
in the initial postoperative period tend to settle well in due course of time ([Video 1]). In the case of subfascial flap harvest, even if there is skin necrosis, the fascia
almost always survives and can be grafted secondarily.
Advantages and Disadvantages of Propeller Flaps
Advantages and Disadvantages of Propeller Flaps
Propeller flaps have their own set of advantages and disadvantages as compared with
other conventional locoregional and free flaps, which are summarized in [Table 2].
Table 2
Advantages and disadvantages of propeller flaps
|
Advantages
|
|
1.
|
It has a unique versatile flap design.
|
|
2.
|
It can be raised as a long and narrow flap and is not limited by routine length-to-width
ratios.
|
|
3.
|
Small-to-moderate size defects are reconstructed reliably in accordance with “like
with like” principle.
|
|
4.
|
Flap harvest is simple, easy, and fast.
|
|
5.
|
Axial rotation of skin paddle gives better aesthetic outcomes without any dog ear.
|
|
6.
|
It is a single-stage microvascular procedure without the need of microvascular anastomosis.
|
|
7.
|
Anatomical variations of major source arteries does not interfere with harvest technique
and final outcome of flap.
|
|
8.
|
By avoiding sacrifice of major vessels, cutaneous nerves, and muscles, donor site
morbidity is reduced.
|
|
9.
|
Linear closure of donor site is possible in many cases.
|
|
10
|
Positional comfort as opposed to distant flap.
|
|
Disadvantages
|
|
1.
|
Patient selection along with good perforator identification is required, which is
dependent on experience.
|
|
2.
|
Propeller flap has a tendency to remain congested in postoperative period and can
be difficult to differentiate between temporary venous congestion and true venous
insufficiency.
|
|
3.
|
Reconstruction of large skin defect and multi-dimensional reconstruction is not possible.
|
|
4.
|
Meticulous dissection is required.
|
|
5.
|
Pin cushion effect has been noted by some authors.
|
|
6.
|
Microvascular anastomosis might be needed for supercharging in case of persistent
venous congestion.
|
|
7.
|
Donor sites of smaller defects can be closed primarily; however, many cases require
skin graft for coverage of donor area.
|
Applications
The perforators from different areas of the body have differing characteristics. Although
that does not greatly affect the technique of harvest or the outcomes, it is prudent
to discuss various applications of propeller flaps in different conditions and anatomical
areas.
Propeller Flaps for the Head, Neck, and Face
The head, neck, and face (HNF) is a favorable site for executing propeller flaps.
This is particularly helped by its anatomical characteristics such as rich vascularity
and extra mobility. The increased mobility in the area gives a great degree of freedom
in the styling of propeller flaps and the placement of suture lines at strategic locations.
Kannan et al[49] have noted that perforators closer to the facial artery origin are larger in size
and the surrounding skin is laxer, and these flaps are more robust compared with other
flaps on the face. Demirseren et al [50] have noted the propensity of propeller flaps over the face for “pin cushioning.”
Therefore, they recommend maintaining an intact skin bridge wherever possible to minimize
this effect. However, in our experience, if the propeller flaps over the face are
planned slightly smaller than the defect and early postoperative scar care and massage
is initiated, the pin cushioning effect is minimized to a great extent ([Fig. 3]). Apart from the use of propeller flaps for cutaneous indications, mucosal and intraoral
flaps can also be designed in a propeller fashion for increased reconstructive options
and possibilities.[46]
[51]
Fig. 3 (a) Malignant lesion. (b) Primary defect over the face. (c) Axial rotation of propeller flap based on facial artery perforators through 180°.
(d) Well-settled propeller flap. (Note: absence or minimal pincushion effect).
Propeller Flaps for the Upper Extremity ([Video 2])
Video 2 Technique of harvest and perforator dissection in upper extremity neurocutaneous
propeller flap
Due to aesthetic concerns, propeller flaps are not as popular for the upper extremity
as they are for the lower extremity.[18] Teo[12] feels that one of the potential limitations to wider application of propeller flaps,
especially in the distal forearm, is the relatively short pedicle length, which might
not be able to withstand a torsion of up to 180 degrees very well. D' Arpa et al [46] noted a high incidence of venous problems in upper extremity propeller flaps. That
might be attributed to the predominance of the superficial venous system, leading
to venous engorgement of the flap based on perforating veins alone. Therefore, they
advocate routine venous supercharging in the forearm.[46]
[48]
Our experience with upper extremity propeller flaps has been very encouraging. We
feel that although the pedicle length and diameter of upper extremity perforators
are less as compared with those of the lower extremity, so is the thickness of skin
and fascia, which is transferred to these perforators.[18]
Decision-making regarding suprafascial or subfascial flap harvest for the upper extremities
deserves special mention. In patients with associated nerve and/or tendon injuries
that might require secondary procedures, we prefer suprafascial flap harvest. This
ensures a smooth subfascial gliding surface for a tendon transfer/graft if required[18] ([Fig. 4]).
Fig. 4 (a) Soft tissue defect over the volar wrist. (b) Islanded flap. (c) Skeletonized perforator. (d) Flap propelled into the defect. (e) Well-settled flap with linear closure of donor site.
Composite propeller flaps are rarely mentioned in the literature. We have limited
experience with the neurocutaneous propeller flap ([Video 2]) for upper extremity reconstruction. More studies and long-term follow-ups are needed
to identify their shortcomings; however, our early results are encouraging.
Propeller Flaps for the Trunk
Despite having a large surface area and a significant number of perforators over that
area, the literature on the use of propeller flaps for trunk reconstruction is sparse.
Moshrefi et al conducted an in-depth review of propeller flap applications for the
trunk with 21 studies and 365 flaps. Interestingly, none of the etiologies mentioned
for the defects were traumatic. They noted no incidence of total flap necrosis.[52] D' Arpa et al noted that the longer length of perforators over the trunk permits
a greater range of movement, allowing an extensive arc of rotation with little concern
about the torsion of the perforator and the blood supply. Studies have demonstrated
that large flaps with an orientation perpendicular to the longitudinal axis of the
cutaneous dermatomes can be successfully transferred to the trunk[53] ([Fig. 5]).
Fig. 5 (a) Defect over the back. (b) Planned free-style propeller flap. (c) Well-settled flap. (Courtesy: Dr. Dushyant Jaiswal, Consultant Plastic, Reconstructive
and Microvascular Surgeon at Tata Memorial Hospital, Mumbai.)
Propeller Flaps for the Lower Extremity
Based on the vascular supply of the lower limbs, it has been observed that very long
propeller flaps can be raised comfortably as compared with other anatomical areas.[46]
[48]
[54] D' Arpa et al have observed that posterior tibial perforators seem to have an advantage
over the perforators of the anterior tibial and the peroneal arteries by virtue of
their large-caliber size and better veins.[46]
[48] However, it has also been noted that the peroneal vessels are relatively resistant
to atherosclerosis. Therefore, if a defect can be covered with a propeller flap based
on perforators of both posterior tibial as well as peroneal vessels, peroneal perforators
should be the source perforator of choice in suspected atherosclerotic extremities
[55] ([Video 1]).
Bajantri et al have described a propeller flap that can be designed from the contralateral
side of the leg and thrown over the intervening skin bridge to cover the defect. They
termed this as the “throwover propeller flap”.[56] We have proposed general guidelines regarding the safe limit of perforator flaps
in lower limb reconstruction by stating the relationship between the length of the
flap and the length of the leg. We found a six-times increased risk of flap necrosis
if the flap is more than one-third of the leg length. However, this study has got
its own set of limitations.[44]
Propeller Flaps for Post-burn Reconstruction
The literature on the use of propeller flaps for post-burn reconstruction is sparse.
Hyakusoku et al,[57] Aslaqn et al,[58] and Karki et al[7] have shared their experience mainly with the use of subcutaneous pedicle propeller
flaps for post burn reconstruction in various anatomical areas. Generally, it is considered
that the local tissue is scarred and not suitable to be elevated as a flap for reconstructing
the local area. Therefore, there might be a reluctance to use propeller flaps for
post-burn reconstruction. However, it has been our experience that including the deep
fascia and a known perforator in the flap makes the flap very reliable. In addition,
the relatively less scarred or unscarred area of the flap goes into the defect, and
the scarred area near the contracture goes into the proximal healthy area[59] ([Fig. 6]). We feel that propeller flaps are an important reconstructive option for postburn
contractures, and the full potential of their applications is yet untapped.
Fig. 6 (a) Post burn wrist contracture with tissue deficit. (b) Primary defect and perforator propeller flap based on ulnar artery perforator (note:
suprafascial harvest of flap). (c) Well-settled flap with linear closure of donor site.
Propeller Flaps in the Pediatric Age Group
There is limited published literature on the use of propeller flaps in the pediatric
age group. Ozalp et al [31] have published their experience with propeller flaps for lower extremity reconstruction
in the pediatric age group. They noted that perforator vessels in children are quite
small in diameter as compared with adults and not easily seen. In their experience
of seven patients, they did not skeletonize the perforators for fear of iatrogenic
injury or vasospasm.[31]
Managing Complications
Most of the complications can be avoided by judicious planning and meticulous execution
of the propeller flaps. Where there is inappropriate patient selection, and haste
in the execution of flaps with disregard to gentle tissue handling and hemostasis,
results are proportionately unpredictable. All these factors have been discussed throughout
the manuscript at appropriate places. Here, we will sum up avoiding and managing complications
under three headings ([Table 3]).
Table 3
Avoiding and managing complications of propeller Flaps
|
Failures
|
Factors leading to complications
|
Avoiding/Troubleshooting
|
|
Inappropriate planning
|
Patient-related systemic factors
|
Chronic tobacco consumers,
PVD
|
Appropriate patient selection
|
|
Defect-related factors
|
Large multidimensional defects,
perforator in the zone of trauma and irradiation
|
Appropriate patient and defect selection.
Avoid propeller flaps in patients with absent Doppler signals
|
|
Inappropriate execution
|
Surgeon-related factors
|
No or less experience in propeller flaps
Inappropriate perforator selection
Forceful tissue handling and traction on perforator
Inadequate Hemostasis
|
Familiarize oneself with local anatomy, planning and execution of propeller flap.
Good quality perforator free from the trauma zone with two venae comitants.
Gentle tissue handling with adequate exposure, illumination, and magnification.
Judicious use of bipolar cautery
|
|
Anesthesia-
related factors
|
Hypothermia and hypotension
|
Warming of IV fluids
Warming blankets
Raising temperature of operation theatre
Adequate fluid replacement
|
|
Inappropriate postoperative care
|
Dressing
|
Compressive dressing
|
Non-compressive dressing with window and splintage.
|
|
Monitoring
|
Inexperienced staff
Whole flap not seen
Doppler over the cutaneous vein or at the wrong place
|
Training of staff on clinical flap evaluation.
Large window to provide access to the entire flap
Intraoperative marking of the perforator for postoperative Doppler position.
|
|
Venous problem
|
Hematoma causing compression
Transient venous congestion
True venous insufficiency
|
Evacuate hematoma and achieve hemostasis
Limb elevation and regular monitoring
Derotation of the flap, venous supercharging, Leech application,
De epithelization of flap.
|
|
Arterial problem
|
Spasm
Persistent spasm
|
Use of lignocaine, papaverine, warm saline, and correction of systemic and extrinsic
factors if any
Derotation of the flap
|
|
Mottling
|
Partial necrosis of flap
|
Avoid aggressive debridement and manage conservatively. ([Video 1])
|
|
Cosmesis
|
Pincushion effect
|
Early postoperative scar care and pressure garments
|
Conclusion
Propeller flaps probably are the latest version of pedicled flaps evolving over the
decades from the original random pattern flaps, and their applications continue to
evolve. Although propeller flaps have their fair share of advantages over other local
flaps, they also have a steeper learning curve as compared with conventional fasciocutaneous
flaps. Applications of propeller flaps in clinical practice are yet to be fully explored
and continue to evolve in terms of appropriate patient selection, identification of
a suitable perforator, and so on. Gentle tissue handling, attention to absolute hemostasis,
and lots of patience are the key points to obtaining good success rates in propeller
flaps.
