A scar is a result of
abnormal healing of wound with a mass of devascularised fibrous tissue covered
by a single layer of epithelium, which contains no skin appendages or no
lymphatics. During the process of healing the blood vessels are constructed by
the collagen fibre of the fibroblasts, hence the scar is relatively
avascular.
Complications :
1. Contracture and deformity
Scar contracts to one-third of its original length.
Effects :
1. Deformity: Especially of flexor surface of joints.
2. Limitation of joint movement :
False ankylosis
Predisposing cause :
- Infection
- burns
Treatment :
Preventive :
- Splinting and early skin graft.
Curative :
- Gradually stretching
- Excision and followed by a skin graft. Pedicle graft can
only prevent subsequent contracture and at times Thiersch graft is better
avoided.
- Z plastic with rearrangement of scar lines.
2. Keloid
Keloid is a vascular hypertrophic
scar. It is actually a form of soft fibroma, prone to recurrence, and is
different from the usual hypertrophic scar.
3. Adherent scar :
Scar adherent to underlying
structures, Example - Scar of muscles to bone or cutaneous scar to
muscles.
Effect :
- Painful during muscular contraction.
- Quadriceps scar adherent to femurrestricts the movement
of the knee joint.
Treatment :
- Active movement.
- Excision - Especially when the cutaneous scar is adherent to
muscle.
4. Painful scar :
Effect :
- Nerve terminal included within the scar - causes local
pain.
- Terminal neuroma, especially in amputation stump.
- Nerve trunk adherent to scar in its course.
Treatment :
- Injection of local anaesthetic.
- Excision of scar, if possible.
- Re-amputation in a terminal neuroma.
- Neurolysis - Release of entrapped nerve.
5. Marjolin's Ulcer :
This is an epithelioma arising from
the epithelium covering the scar.
Effect :
- It is a very slow-growing tumour as it is not very
vascular.
- It is not painful as there are no nerve
terminals.
- Lymphatic metastasis does not occur as there are no
lymph vessels.
Diagnosis :
- Ulcer developing over a scar.
- Very slow-growing.
- Foul-smelling discharge due to invasion by saprophytic
organisms.
- Irregular hard ulcer with everted margin.
- Regional lymph glands not palpable.
Treatment :
- Early case : Wide
excision followed by skin graft and deep X-ray.
- Late case : Amputation
if possible.
6. Ulcerated scar :
These are callous ulcers from
impaired nutrition. The epithelium cracks and forms ulcer.