21 - Mechanical and Biomechanical Skin Lesions Flashcards
1
Q
What to focus on
A
- **Recognize the characteristics associated with each of the lesions **
- Know the specifics and any distinguishing features
2
Q
Mechanical lesions of the foot
A
- Hyperkeratosis
- Forms of calluses
- Callus location and types
- Classification of helomas
3
Q
Hyperkeratosis
A
- Thickening of the skin
- Stimulation of the epidermis by increased or chronic pressure or friction
- Increased keratinocyte activity
- Normal protective response
4
Q
Causes of hyperkeratosis
A
- Mechanical stresses (improper or poorly fitting shoes)
- Abnormal foot mechanics (bony or biomechanical deformities)
- High levels of activity
5
Q
Two types of calluses
A
o Diffuse shearing callus
o Discrete-nucleated callus
6
Q
Diffuse shearing calluses
A
- Usually a flat lesion, but you really need to palpate the callus to determine the thickness of the callus and the skin around it
- Weight bearing surface of the sole
- Usually asymptomatic – typically NO pain
- Pain can occur if they dry and fissure
- Even thickness, undefined margins
- Related to abnormal shearing/friction forces
7
Q
Treatment for diffuse shearing calluses
A
- control abnormal pronation
- tissue debridement
- surgery
8
Q
Discrete nucleated calluses
A
- Usually isolated and PAINFUL
- Central conical core of keratin at greatest pressure – not just flat, there is a CORE associated with it!
- Can often be confused with plantar wart
- Plantar warts are more sensitive to side-to-side compression, whereas this callus causes pain with directed pressure
9
Q
Treatment for discrete nucleated calluses
A
- Controlling abnormal pressures
- Cushioned inserts
- Prescription orthotics with an accommodative area
- Periodic local tissue debridement with protective padding to reduce pain
- Surgical correction of underlying bone pathology
Example of surgical correction
- Example: plantarflexed metatarsal head or osteophyte/bone spur
- Can relieve pain by surgically fixing the biomechanical/osseous deformity
- NOTES: might want to be a little more aggressive with the treatment of this, because they will be in pain and you will be able to give them relief by debriding – some of these can be very deep
10
Q
Classification of calluses
A
- Porokeratosis plantaris discreta
- Superficial shearing callus
- Superficial fibrous shearing callus
- Fibrous nucleated shearing callus
- Pinch callus
11
Q
Porokeratosis plantaris discrete
A
- **NOTE: ALWAYS ASSOCIATED WITH A SWEAT DUCT **
- 1-3 mm punctate lesion
- Weight bearing aspect of sole
- Direct pressure from plantar surface
- Sweat duct involvement (can see moisture during debridement)
- Hyperkeratosis of epidermal sweat duct
- No vascular involvement
- Can be as deep as 1.5 cm
12
Q
Treatment of porokeratosis plantaris discrete
A
- Topical keratolytics (20% urea cream will suffice - might not get rid of the lesion completely, but it will help to maintain it so they don’t have to come back to get it down as often)
- Periodic debridement
- Alcohol sclerosing injections – completely destroys the sweat duct
- Surgical excision of the lesions – scar formation will be minimal, so it may not be any significant downfall of surgical excision (can be as deep as 1.5 cm, which is very deep, so you will need to use a 64 blade which is rounded to scoop out the lesion)
13
Q
Superficial fibrous shearing callus
A
- Clear keratin nucleus with white fibrous base that blends into surrounding callus
- Painful when hypertrophic
- Debridement
14
Q
Fibrous nucleated shearing callus
A
- Deep nucleus with white fibrous plug – may have a flat callus, but in the central portion, there will be a nucleus associated with it
- Clearly differentiated margin
- Enucleation painful
- Must remove plug to get relief
15
Q
Treatment of fibrous nucleated shearing callus
A
o Debridement
o Curettement
o Bone surgery (for underlying etiology if there is a bony prominence)