Atzei classification of peripheral TFCC tears

The Atzei classification of peripheral triangular fibrocartilage complex (TFCC) tears offers a more differentiated approach on a spectrum of peripherally located triangular fibrocartilage complex (TFCC) tears, which are classically summarized as “Palmer 1b” lesions ^1-3.

Usage

Peripheral lesions are more amenable to surgical repair, because the periphery is better vascularized than the central portion and the radial attachment, and thus can better heal once repaired, whereas lesions in the central avascular zone do not ⁴.

This classification comprises clinical, radiographic and arthroscopic criteria and it subclassifies lesions in respect to distal radioulnar joint (DRUJ) stability, the involvement of distal (styloid),  proximal (foveal) or both triangular fibrocartilage complex (TFCC) attachments and the different treatment options for those tears ^1-3. 

It also offers clear therapeutic recommendations for each category, which is a distinctive strength of this classification ^1-3.

Classification

Atzei class 1

• isolated tear of the styloid attachment
  • clinically stable distal radioulnar joint *
  • arthroscopically peripheral tear, negative Hook test
  • normal distal radioulnar joint cartilage
• recommended therapy: suture

Atzei class 2

• complete but repairable tear of both the styloid and foveal attachments 
  • clinical signs of instability of the distal radioulnar joint *
  • arthroscopically peripheral tear, positive hook test
  • normal distal radioulnar joint cartilage
• recommended therapy: suture and foveal refixation

Atzei class 3 

• isolated tear of the foveal attachment or bony avulsion fracture of the styloid
  • clinical signs of instability of the distal radioulnar joint *
  • arthroscopically, normal appearance, positive hook test
  • normal distal radioulnar joint cartilage
• recommended therapy: foveal reattachment or styloid fixation in case of an avulsion fracture

Atzei class 4

• extensive tear or tear with poor healing properties not suitable for repair
  • clinical signs of instability of the distal radioulnar joint *
  • arthroscopically extensive tear with degenerated or frayed edges, positive hook test
  • normal distal radioulnar joint cartilage
• recommended therapy: reconstruction e.g. with tendon-graft

Atzei class 5

• peripheral tears associated with distal radioulnar joint arthritis or osteochondral injury
  • variable clinical signs
  • arthroscopically, peripheral tear, positive hook test
  • degenerative or traumatic cartilage defect of the distal radioulnar joint 
• recommended therapy: arthroplasty or joint replacement

*distal radioulnar joint stability clinically assessed by the ulnar fovea sign and ballottement test

History and etymology

This classification of peripheral triangular fibrocartilage complex (TFCC) tears has been first described by the Italian wrist surgeon Andrea Atzei ^1-3.

See also

• triangular fibrocartilage complex (TFCC)
• triangular fibrocartilage complex (TFCC) injury
• Palmer classification of TFCC abnormalities