How to perform combined flaps

With combined flaps, you can use multiple flaps in one design, which is helpful for correcting contractures in folds, such as the elbow crease or knee.

General principles

Combined flaps offer an additional option for treating burn contractures, next to the Z-plasty and interposition flaps. With this technique, you can combine multiple flaps into one design. It works well because post-burn contractures tend to form a fold with an affected (burned) side and a non-affected side. 

One combined flap design is a five-flap plasty that is often very effective in burn contracture reconstruction. It is a double-opposing Z-plasty combined with a central Y-V advancement. This is also known as the ‘jumping man’ flap, as it resembles a person jumping. The jumping man configuration can also be described as three release incisions on the affected scarred side, followed by three interposition flaps from the healthy side.

Figure 1: The jumping man flap

Several designs exist; here we use the design by Hirshowitz as an example. It is formed by two mirrored Z-plasties, with an extra incision that allows the possibility of a Y-V advancement. 

To be effective, it is important to harvest from the healthy side the three triangular flaps to be transferred into the release incisions on the contracted side. The tetrahedral effect ensures that length and depth will be gained. This makes the combined flap well suited for correcting burn contractures, particularly those with a fold that has an affected and a non-affected side.

The combined flaps procedure is well suited for correcting contractures in folds – for example, a burn contracture of an axilla, elbow crease, webspace of the hand, finger, or knee fold.

Considerations

Combined flap designs require specific three-dimensional features in order to be feasible. In general, you cannot usually perform them on a flat plane (in two dimensions) because the tissue you need to recruit from the sides simply cannot reach the required position for the plasty.

Combined flaps work best when the contracture has formed in a fold or crease, creating extra tissue in the third dimension. In practice, one side of the fold is often badly scarred, while the other side has good quality skin, therefore proper design is of utmost importance.

Procedure

This guidance covers the combined flaps procedure from preparation, including the surgical instruments you will need, to the evaluation of results.

Preparing for combined flaps surgery

Surgical instrumentDetails
Surgical PenUse a good quality water resistant marker. Making a preoperative drawing is an essential part of the procedure. 
RulerMeasures the slack and the length of the limbs of the Z-plasty to make sure they are the same length; a protractor can be useful but most surgeons can estimate the angles adequately by eye.
ScalpelUsually with a #10 or #15 blade, depending on the size of the Z-plasty.
Dissecting forcepsSuch as Adson or other fine tissue forceps.
Handheld retractorsSuch as small single toothed skin hooks for small Z-plasties, or Senn retractors for larger Z-plasties.
ScissorsSuch as Metzenbaum or Iris.
Mono or bi-polar electrocauteryThis equipment is not always essential when using jungle juice, but it can be helpful if available.
Needle holdersAny standard needle holder.
SuturesA non-absorbable, monofilament suture will usually suffice, though larger Z-plasties under a lot of tension may require an absorbable suture in the dermal plane.

Marking the flap design

Pay attention to your design!

Five-flap plasties will fail if the triangular flaps are projected onto the scarred side, and the rectangular flaps onto the healthy side.

Before marking the flap, it is essential to determine the line of maximum tension (the direction of the contracture). You can do this by extending the affected joint or body part. It is also important to determine which side of the contracture contains the most damaged skin and which side contains the healthy skin.

After you have assessed the affected area, mark the design of the five-flap plasty. You usually do not draw the arms of the jumping man at the start; instead, draw these after you have mobilized the two lateral triangular flaps.

The line between the two rectangular flaps and the three triangular flaps should be in line with the contracture (perpendicular to the axis of rotation of the joint).

The two rectangular flaps (with the releasing incisions) should be located on the side with the most affected, contracted tissue.

The three triangular flaps should be located on the side with the most healthy, unaffected tissue.

Anesthesia

You can perform a five-flap plasty under local (WALANT), regional, or general anesthesia, depending on the location of the contracture, the estimated size and extent of the surgery, and patient characteristics.

For example, you would perform a small five-flap plasty to release a webspace contracture in an adult under local anesthesia, whereas general anesthesia would be more suitable for a large five-flap plasty on an elbow burn contracture in a child.

When using local anesthetic, anesthetize first and then disinfect and drape. This ensures that the anesthetic has sufficient time to work properly.

Even if the procedure is performed under general or regional anesthesia, infiltrate the operative site with local anesthetic and adrenaline/epinephrine. This will greatly reduce the bleeding during the operation, make the dissection easier, and provide postoperative pain relief. Allow 30 minutes for the adrenaline/epinephrine to have the optimal effect and use a long-lasting local anesthetic agent for optimal postoperative pain relief.

Positioning

The positioning of the patient depends on the location of the burn contracture.

Sterilization and dressings

Make sure that the entire site is disinfected and that the sterile drapes do not restrict movement, so that the affected body part can move freely during the procedure. This can help improve exposure and allows you to assess the effect of the contracture release immediately.

Surgery

Contractures are characterized by problematic amounts of skin tension. Due to this tension, the skin on the side of the contracture has a tendency to shrink and the tetrahedral effect of combined flaps is challenging to predict. Therefore, we advise dissecting the releasing incisions and the interposition flaps in stepwise fashion. Doing so gives you the opportunity to alter the design if necessary.

  1. Start with the incision in the direction of the contracture (the shoulders of the jumping man).
  2. Continue with the releasing incisions (the head of the jumping man) through all fibrotic scar tissue, then make the incisions forming both legs of the jumping man.
  3. Raise the central triangular flap in between the legs of the jumping man. In an ideal situation, the Y-V advancement will reach the tip of the V almost at the level of the pivot point of the joint.
  4. After you have lifted the central triangular flap, you can raise the two lateral triangular flaps on the healthier side of the contracture. By turning the lateral triangular flaps to their new position on the more affected side, the best position of for the lateral incisions of the rectangular flaps (the arms of the jumping man) become clear, and you can make adjustments if necessary.
  5. In a well-designed five-flap plasty, the flaps will almost fall into place by themselves. Make sure that all dissected flaps are the same thickness all over, or slightly thicker at the base. The dissection can be within the subcutaneous tissue if this layer is extensive, but often a supra-fascial plane is preferable to ensure maximum blood supply to the flaps.
  6. Check for active bleeding and coagulate if necessary. Be cautious when coagulating on the skin flap as this could damage the vascularization.
  7. When suturing the five-flap plasty, start by putting the tips of the three triangular flaps in their new positions. You can use subcutaneous sutures to minimize tension on the skin.
  8. We advise using monofilament sutures for the skin. In small children or difficult anatomical locations absorbable sutures can be convenient, as they avoid the need for removal.
  9. Depending on the size and location, you can place a small drain.

Contracture release of the left elbow using the jumping man method, step-by-step.

Dressing and fixation

In most cases, you can apply a simple dressing with dry gauzes as a first layer. If the flaps tend to move away from the underlying tissue layer (this is called ‘tenting’), you can apply an elastic bandage or even a tie-over dressing.

Joints that have been affected by a contracture tend to return to their contracted position, and you must avoid this. Therefore, we advise fixation of the affected joint in a position opposing the contracture until the wounds have healed. You can achieve this with a Plaster of Paris slab splint. K-wires are a very useful alternative in the hands, fingers, and toes, where plaster may be less effective, especially in young children.

Postoperative care

After surgery, change the dressing after 3-5 days, or earlier if there is a risk of infection. Remove sutures after 2-3 weeks if they are non-absorbable. If you used K-wires, remove them after 3-4 weeks due to the risk of infection.

You can continue splinting for a longer period, until there is no further risk of the contracture recurring. If the affected joint is not fixed for long enough in the position opposing the contracture, there is a high risk of contracture recurrence.

Physiotherapy

The patient should start active movement and exercises as soon as wound healing permits to maintain the ROM they gained. The availability of physical therapy makes a big difference. If physical therapy is not available, emphasize the importance of exercises to the patient and provide adequate instructions.

You can continue splinting between exercises and during the night. Splinting during the night is sometimes continued for months, even after the wounds have fully healed and the affected limb has returned to normal use.

Splinting works well when the skin quality is good, but it is less effective for stretching remaining scar tissue. In these cases, additional surgery to add extra tissue where needed may be more effective, followed again by appropriate positioning after the additional procedure.

Evaluation of results

We recommend reevaluating the patient until the scars have healed, ideally at least after six weeks, three months, six months, and one year. Measure and document the ROM preoperatively and monitor the development of ROM postoperatively. Explained to the patient that the ROM can continue to improve for months, provided they do their exercises. One year post-procedure, you can make the final measurement and evaluate the result together with the patient.

Management of complications

As burn scars are very fibrotic and therefore often poorly vascularized, complications in wound healing are common. Wound breakdown, necrosis, and infection are the most common complications. This is particularly true when wounds are closed under skin tension. If a local flap such as a jumping man does not provide enough tissue to close the wound without tension, we advise either adding a skin graft or accepting that the joint cannot be fully extended (yet).

You can start antibiotic treatment when indicated for infection. Treat small areas of necrosis and minor wound breakdown conservatively by cleaning the wound and applying antibacterial dressings. The small defects will heal by secondary intention and the end result will often still be adequate in terms of contracture release, so no further treatment will be required.

Surgically debride larger breakdowns with extended necrosis. If the defects are substantial (for instance a complete triangle has become necrotic), treat the area with a skin graft as soon as the wound bed allows, and continue splinting.

How to perform combined flaps

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