Keratotic Deformities

Definitions

 

Corn

- accumulation of keratotic layers of epidermis

- thickened epithelium elevates prominence causing further pressure

 

Hard Corn

 

Due to extrinsic pressure from footwear

- most common on lateral aspect of 5th toe

- over head of proximal phalanx

 

Soft Corns

- on the condyle of proximal phalanx between the toes

- due to pressure between adjacent bony prominences

- DDx fungal infection

- soft due to moisture

- commonest is medial aspect 5th toe

- also common at base of web space overlying 4th proximal phalanx lateral condyle

 

Aetiology

 

Combination of Extrinsic or Intrinsic pressure

 

Extrinsic 

- shoewear increasing compression 

 

Intrinsic 

- underlying prominent condyle of P1

 

X-ray 

 

See on plain film with marker over corn

 

Non-operative Management

 

Usually not successful long term

- education re shoewear / wide shoe with extra depth toebox

- lambs wool dressing or foam pads

- trim hyperkeratosis

 

Operative Management

 

Isolated small keratosis over 5th PIPJ

- treat with condylar resection of 5th PIPJ alone

 

Keratosis over 5th PIPJ & base 4th web

- treat with resection of 5th condyle & lateral proximal phalangeal condyle of 4th toe

 

Intractable Plantar Keratoses

 

1.  Resection Arthroplasty of Mann and DuVries 1973

 

Results

- 85-90% patient satisfaction

 

Technique

- dorsal Incision over MTP

- retract EDL

- divide transverse MT ligament

- severe collaterals and deliver head

- remove 2-3mm of distal MT head

- remove the plantar lip so approximately 50% of head has been excised

 

2.  Giannestra Shortening Oblique MT Osteotomy

 

Best when long MT

- aim to shorten 5-6mm

- fix with screw

 

3.  Dorsal Closing Wedge Osteotomy

 

Aim for dorsal wedge of 2-3mm

- fix with cross K-wires

- must pop for 6/52