Hand Scars: When Is Further Treatment Needed?

Functional Impact

Hand scars differ from scars on other parts of the body primarily because the hand is involved in actions such as grasping, extending fingers, opposing the thumb, spreading fingers, writing, washing the face, and dressing. Even a small scar, if it crosses a joint, web space, palm skin, or the thumb-index web, can affect daily life.

Although the hand accounts for only a very small portion of the body's surface area, hand burns are common among burn patients. Burn studies report that 26% to 90% of burn patients may also have hand burns. In addition to reduced mobility, hand burns can affect quality of life and social recovery.

Hand scars are commonly seen after burns, scalds, thermal compression injuries, electrical injuries, crush injuries, contusions, cuts, and surgeries. Superficial scars may only show color changes or slight thickening, while scars from deep injuries may gradually harden, shorten, and pull on fingers, metacarpophalangeal joints, interphalangeal joints, and web spaces, leading to scar contracture. Thermal injuries to the hand often result in skin scar contracture and hand dysfunction, making appropriate corrective treatment and functional rehabilitation crucial for such injuries.

Signs of hand scars to watch for

When determining whether a hand scar requires further treatment, the size of the scar is an important factor. Additionally, it is essential to observe whether it affects hand function.

It is recommended to seek evaluation from a plastic surgeon or hand surgeon as soon as possible in the following situations: inability to fully extend fingers; inability to make a tight fist; inability to open the palm; narrowing of the thumb-index web, difficulty in thumb abduction or opposition; shallowing of the web spaces, inability to spread fingers; scar crossing a joint and continuing to harden; claw-like hand appearance due to scar tension on the back of the hand; increasing finger curvature in children as they grow; recurrent scar ulceration, pain, itching, or interference with wearing gloves or using tools.

Finger flexion contracture is a common issue. In a study involving 21 patients with palmar scar contracture following thermal injury to the hand, all exhibited flexion deformities of the metacarpophalangeal or interphalangeal joints, with the affected fingers unable to fully extend. The duration of the condition ranged from 6 months to 43 years. After treatment, the affected joints were completely or nearly corrected, with the total range of motion improving from approximately 152.71° preoperatively to about 227.83° postoperatively. This indicates that even long-standing scars can potentially have functional improvement with appropriate treatment.

Mild scars can be treated non-surgically at first

For early-stage, mild hand scars without significant tension, non-surgical treatments are usually considered first. Common methods include pressure gloves, silicone gel or sheets, scar massage, thermotherapy, splints, physical therapy, functional training, laser treatment, and medication injections.

The goal of these treatments is to soften, flatten, and lighten the color of the scar while maintaining joint mobility as much as possible. Early intervention is often easier than addressing significant finger bending later on. The hypertrophic phase of a scar can last several months to a year or two, during which increasing tightness, hardness, and reduced range of motion may necessitate other treatment options.

When are splints and rehabilitation appropriate?

Splint therapy is suitable for some patients with hand scar contracture or functional impairment, especially when joints can still be passively moved, the skin retains some elasticity, and there are no severe bone or joint deformities. Splints not only stabilize the hand but also provide continuous, controlled, gentle stretching to help gradually lengthen the skin, scar, and soft tissues, while active training aids in functional recovery.

Do not delay treatment for children's hand scars

Children's hand scars require more proactive follow-up because children are growing, and the bones, skin, and soft tissues of the fingers are changing. Scar tissue lacks the elasticity of normal skin, which can lead to the problem of 'growing tighter' over time.

After healing from deep second-degree or third-degree hand burns, children are prone to developing hypertrophic scar contractures, which can affect appearance and may cause functional abnormalities or even growth and developmental issues. Proper rehabilitation can prevent and reduce scar hypertrophy, minimizing functional impairment and developmental abnormalities.

For children who cannot visit the hospital daily for rehabilitation, home rehabilitation is also valuable. A study divided 30 children with deep second-degree or third-degree hand burn scar contractures into a home rehabilitation group and a hospital rehabilitation group. The home rehabilitation group received training in the hospital for 1-2 weeks and then received guidance from a rehabilitation therapist via WeChat, using pressure gloves, hand flexion training bands, and finger separation splints. After six months of treatment, both groups showed significant improvement in joint mobility and limb function, with home rehabilitation being comparable to hospital rehabilitation.

Evaluate surgery when the fingers cannot straighten, the thumb web cannot open, or the finger web spaces become shallow

If the fingers are fixed in a bent position and cannot be straightened actively or passively, simple massage, silicone, and laser treatments are often insufficient. It is necessary to assess the extent of the scar band, joint angles, skin defects, available surrounding skin, and the condition of tendons and neurovascular structures before choosing Z-plasty, serial Z-plasty flaps, local flaps, skin grafting, perforator flaps, free flaps, or staged reconstruction.

For pediatric hand hypertrophic scar contractures, a study involving continuous Z-plasty combined with scar volume reduction included 27 children and 36 joint sites. The study categorized the contractures of the metacarpophalangeal or interphalangeal joints into mild, moderate, and severe: mild to moderate cases were treated with continuous Z-plasty for release and scar volume reduction followed by wound closure, while severe cases were covered with flaps after complete release, with residual wounds grafted. Follow-up over 1-2 years showed complete correction of all contracture deformities, with no recurrence.

When surgery is more necessary

Further treatment of hand scars does not necessarily mean surgery, but surgery becomes very necessary in the following situations: the scar has caused joint fixation deformity; there is significant limitation in finger extension or flexion; web space contracture affects thumb use; shallow webbing affects finger separation; anticipated skin defect after scar excision; possible exposure of deep tissues, bones, tendons, or joints; worsening of pediatric scars with growth; conservative treatment for 3-6 months shows no significant effect; recurrent scar ulceration or impact on work and life.

Scar excision is only part of surgical treatment; scar repair surgery also needs to address the following issues: release of tension, correction of deformity, and coverage of defects.

For patients with cord-like or linear scars and favorable surrounding tissue conditions, Z-plasty can be used to extend the scar direction; if there is no exposure of deep tissues after scar excision, skin grafting can be chosen; if deep tissue exposure or large skin defects are present, local flaps or other flap repairs are needed.

How doctors assess hand scars before treatment

A standardized assessment includes the location, area, thickness, color, and softness of the scar, whether there is pain or itching, any ulceration, active and passive range of motion of the joints, whether the fingers can straighten, make a fist, and oppose, the shape of the web space and interdigital folds, sensation and blood supply, history of skin grafting or surgery, and in children, growth and development should also be considered.

Ordinary patients can record several pieces of information before visiting the doctor: the time of injury, how long the wound took to heal, whether skin grafting was performed, whether surgery was done, when the scar started to tighten, which movements are restricted, whether there is pain or numbness, and whether fine hand function is required for daily work. Taking photos of the hand in natural extension, making a fist, palm up, back of the hand up, thumb abduction, and fingers spread can also help the doctor assess changes.

Postoperative rehabilitation determines long-term outcomes

After hand scar treatment, rehabilitation is a crucial part of achieving long-term outcomes. If functional training, pressure therapy, and splint management are not performed after surgical release, the newly formed scar may contract again.

Rehabilitation training should be conducted according to the plan of the doctor and therapist, and brute force should be avoided. Excessive stretching can cause skin blisters, tearing, and increased pain, and children may resist training due to pain. A more appropriate approach is regular follow-up, with gradual adjustments based on the softness of the scar, joint mobility, and skin tolerance.

To what extent can hand scars recover

The degree of recovery depends on: the depth of the scar, the number of affected joints, the duration of the condition, whether there is concurrent tendon or bone joint damage, the condition of the skin donor site, the surgical method, and adherence to rehabilitation.

Patients with simple skin scar contracture and minor deep structure damage usually have a greater potential for functional improvement; those with long-term severe contracture, repeated surgeries, joint stiffness, tendon adhesions, sensory deficits, or children whose growth and development are affected may require staged treatment.

The goal of hand scar treatment is to make the appearance as natural as possible while maintaining the hand's functional capabilities. Mild issues can be improved with pressure, silicone, laser, splints, and rehabilitation; moderate to severe contractures require surgical release and repair; complex defects may need flap or microsurgical reconstruction. The earlier it is determined whether a scar affects function, the easier it is to preserve hand mobility.