Reconstructive Treatment for Post-Burn Scar Contracture

Burn Scars

Post-burn scar contracture refers to the thickening, hardening, and shortening of scar tissue after a burn wound has healed, which gradually pulls on the surrounding skin, muscles, joints, and facial structures, leading to deformity or restricted movement.

Burn scar contractures are commonly seen in patients with deep burns, extensive burns, burns around joints, prolonged wound healing time, insufficient early rehabilitation, or recurrent infections.

Scarring is a common outcome in the healing process of burn wounds. Burn scars on the head, face, and neck can even cause restricted breathing, mouth opening, and joint movement, significantly affecting appearance. Simple skin grafting or local flap repair may sometimes encounter issues such as scar recurrence, color mismatch, and donor site insufficiency.

Therefore, the treatment of post-burn scar contracture is a gradual and comprehensive process that requires the release of contracted tissues and coverage of the wound with more suitable skin, flaps, or artificial dermis.

When is reconstructive treatment needed

Mild scars can initially be managed with pressure therapy, silicone, laser, drug injections, splints, and rehabilitation training. However, if there is significant contracture, restricted joint movement, facial deformity, difficulty opening the mouth, closing the eyes, raising the arms, or limitations in neck movement, or if fingers cannot be fully extended, an evaluation by a plastic surgeon or burn specialist is necessary.

The objectives of reconstructive treatment include: releasing contractures, restoring joint range of motion, improving aesthetic contours, reducing the risk of recurrent contractures, and enhancing daily living abilities. For children and adolescents, subsequent growth and development must also be considered. For patients with extensive burns, it is important to assess whether there is sufficient donor skin available, whether the donor site also has scars, and whether the patient can tolerate staged surgeries.

What will the doctor evaluate before treatment

First, the specific location of the scar contracture must be considered, such as the neck, axilla, antecubital fossa, fingers, web space, popliteal fossa, ankle, perioral area, and eyelids, where functional demands are high and treatment plans are more complex.

Second, the depth and extent of the scar must be considered, such as whether it is a linear band, web-like constriction, or a large area of hardened scar; whether it affects a single area or multiple joints simultaneously.

Additionally, local skin blood supply, presence of ulceration or infection, availability of normal surrounding skin, and whether the patient has previously undergone skin grafting or flap surgery must be considered.

Preoperative assessment also includes measuring joint mobility, such as focusing on shoulder abduction angle in axillary scar contracture, evaluating active and passive finger movement in hand scars, and assessing cervicomental angle, mouth opening, neck flexion, extension, and rotation range in neck scars.

Neck Scar Contracture: Focus on Restoring the Cervicomental Angle and Neck Mobility

Post-burn neck scar contracture can cause the chin and chest to be pulled together, sometimes resulting in a 'head-down fixation' posture, affecting head lifting, swallowing, speaking, airway management, and facial development. Therefore, during neck reconstruction, it is crucial to restore the natural contour of the mandibular margin, chin, anterior neck region, and supraclavicular area.

A study on surgical strategies for post-burn neck scar contracture included 65 patients, with scar release performed according to the three anatomical subunits of the neck; some patients with mandibular retraction also underwent genioplasty. Wound coverage followed the 'similarity principle,' selecting tissues with similar color, texture, and thickness as much as possible. In the study, 32 cases used local flaps, 7 used adjacent flaps, 11 used free flaps, and 15 used skin grafts; all grafts and flaps survived, with good postoperative neck mobility, and the reconstructed cervicomental angle reached 90°—120°.

From a layperson's perspective, the key points in neck scar reconstruction are: completely releasing the scar contracture as much as possible, fully covering the contracture site, and achieving a repaired shape that closely resembles the natural appearance.

If the release is done without proper coverage, the new wound is prone to re-contract; if the flap is too thick, the neck contour may appear bulky; if the graft is too thin, it may contract again later.

Therefore, the surgeon will choose local flaps, adjacent flaps, expanded flaps, free flaps, or skin grafts based on the size of the defect.

Axillary Scar Contracture: Focus on Restoring Arm Elevation Function

Axillary scar contracture is common in patients with simultaneous burns to the upper arm, chest, back, and axilla. Patients may experience difficulty raising their arms, dressing, washing their hair, and may notice a shallower or deformed axilla. Axillary scar contracture can be classified into different types, with severe cases involving the anterior wall, posterior wall, apex of the axilla, and surrounding tissues. Patients with extensive deep burns often have axillary scar contracture, leading to limited shoulder abduction and axillary structural deformity. Treatment options include skin grafting, five-flap plasty, local flaps, and free flaps.

For severe axillary scar contracture, flap repair is often more stable than simple skin grafting. A study using circumflex scapular artery perforator flaps to treat severe post-burn axillary scar contracture included 38 patients. Preoperatively, shoulder abduction was only 20°–70°, but postoperative shoulder range of motion and function improved significantly. Follow-up from 6 months to 3 years showed shoulder abduction angles greater than 90°, with no recurrence of axillary scar contracture.

Another study on type IV axillary scar contracture after extensive burns used rectangular scar flaps combined with autologous split-thickness skin grafts. All six patients' rectangular scar flaps survived, with follow-up from 18 months to 3 years showing minimal axillary scar hypertrophy and mild graft contracture. At 18 months postoperatively, shoulder abduction reached 180°. This indicates that axillary reconstruction must address skin tension and reshape the three-dimensional space of the axilla.

Hand and Web Space Contracture: Focus on Restoring Grip and Fine Motor Skills

The hand is one of the areas most in need of active management for post-burn scar contracture, as finger flexion contracture affects extension, grip, writing, and using chopsticks. Web space contracture limits thumb abduction and opposition, severely impacting overall hand function. Syndactyly contracture prevents finger separation, affecting fine motor skills.

Particular attention should be paid to children's finger burns, as children are in a rapid growth phase, and the growth capacity of free skin grafts differs from that of surrounding normal skin, potentially lacking long-term stability. For instance, a study on recurrent deformities after multiple finger burn contracture surgeries showed that using continuous cross-shaped flaps combined with palmar multiple Z-plasty and scar volume reduction surgery in 9 children, without skin grafting during surgery, resulted in no flap infection or necrosis postoperatively. Follow-up over 8 to 32 months revealed that the reconstructed web space depth, width, and slope were close to normal, with hand function evaluation showing 8 excellent and 1 good result.

Reconstruction of the first web space and complex syndactyly sometimes requires microsurgical techniques. A study on severe post-traumatic first web space contracture showed significant improvement in the width and angle of the first web space in 43 patients using various flaps. Research on complex syndactyly also suggests that dorsal or hand island flaps are suitable for small defects, dorsal interosseous artery flaps for medium-sized wounds, and paraumbilical and anterolateral thigh flaps for large or irregular defects, with sensory recovery flaps yielding better outcomes.

Artificial dermis and skin grafting: Suitable for insufficient skin source or functional site reconstruction

Patients with extensive burns often face a practical issue: insufficient normal skin available for grafting.

Traditional skin grafting can cover wounds but may result in re-contraction, pigmentation differences, or poor texture at joints and functional sites. Artificial dermis can serve as a dermal substitute, forming a relatively stable tissue base on the wound before secondary autologous skin grafting.

A study on the use of artificial dermis in late-stage functional reconstruction after severe burns included 40 patients, comparing artificial dermis combined with autologous split-thickness skin grafts to traditional autologous medium-thickness skin grafts. Results showed that the early graft survival rate in the artificial dermis group was similar to the traditional group, but the VSS scores for scars in both recipient and donor sites were lower, donor site healing time was shorter, and functional site recovery was improved. This method is suitable for patients with extensive burns, limited skin sources, and a high risk of recurrent contracture at functional sites.

Expanded Flaps: More Refined Reconstruction with Similar Skin

Skin and soft tissue expansion is one of the common methods used in post-burn scar reconstruction. Plastic surgeons place an expander under available skin either adjacent to or distant from the scar, periodically injecting saline to gradually increase the skin volume. The expanded flap is then transferred to the defect area after scar excision.

Post-burn scars on the head, face, and neck have high aesthetic demands, and donor sites are often insufficient. Expanded flaps can provide a large amount of tissue similar to the defect area.

Expanded flaps can better match the recipient area in terms of color, texture, and thickness, and reconstruction can be completed through various designs and transfer methods. However, expansion treatment requires time and carries risks such as infection, expander exposure, flap necrosis, and discomfort during the injection process, requiring strong patient cooperation.

Postoperative Rehabilitation Determines Functional Maintenance

Reconstruction of burn scar contracture is only the first step in the entire treatment process. The new wound will still undergo a scar formation process, and without rehabilitation, the released joints may become tight again.

Additionally, postoperative management for the hand often requires splint fixation, active and passive movement training, pressure gloves, silicone gel, scar sheets, and laser therapy as part of comprehensive management.

For axillary scar contracture, postoperative care involves gradually increasing shoulder joint abduction exercises; for neck scar contracture, maintaining head elevation, head rotation, and cervicomental angle is necessary; for hand scar contracture, early restoration of fist clenching, finger extension, thumb opposition, and finger separation is crucial, as inadequate rehabilitation is one of the key reasons for scar contracture recurrence.

To what extent can post-burn scar contracture be restored?

The degree of recovery depends on numerous factors such as burn depth, scar extent, affected area, duration of joint stiffness, local tissue conditions, surgical methods, and postoperative rehabilitation. Early, smaller-scale contractures without severe joint stiffness usually have better recovery outcomes; patients with a long disease course, repeated surgeries, involvement of deep tendons and joints, and insufficient skin sources often require staged treatment.

Overall, modern reconstruction of burn scar contractures is no longer as simple as skin grafting. Plastic surgeons may choose methods such as Z-plasty, local flaps, perforator flaps, expanded flaps, free flaps, artificial dermis combined with skin grafting, and microsurgical reconstruction based on the location.

The treatment goal is to enable patients to raise their arms, straighten their fingers, open their mouths to speak, and lift and turn their heads, while also improving appearance and quality of life as much as possible. For complex contractures following severe burns, the earlier a professional assessment is conducted, the easier it is to develop an appropriate staged treatment plan and rehabilitation program.