There are 5 Flexor and 9 Extensor Zones of the Hand. They are used to describe the location of a tendon injury, guide post-operative therapy and predict prognosis.
5 Key Points
- Origin: based on work by Kleinert and Verdan in the 1980s.
- Flexors: 5 volar zones described relative to soft tissue structures.
- Extensors: 9 dorsal zones described relative to bony structures.
- Thumbs: Different zones of the hand, referred to as "T".
- Use: describe injuries, guide rehabilitation, predict prognosis
Flexor Zones of the Hand
There are in total 5 flexor (volar) zones on the volar aspect of the hand1,2,3:
- Zone 1: Distal to FDP Insertion
- Zone 2: Proximal A2 Pulley to FDP Insertion
- Zone 3: Carpal Tunnel to Proximal A2 Pulley
- Zone 4: Carpal Tunnel
- Zone 5: Proximal to Carpal Tunnel
- T1: Distal to A2 Pulley
- T2: A2 Pulley to A1 Pulley
- T3: A1 Pulley to Carpal Tunnel
These flexor zones of the hand are illustrated below.
The location of flexor zones and their clinical significance are in the table below. For example:
- Zone II injuries are often explored through a Bruner's or mid-lateral incision.
- Zone I finger replants often have better post-operative outcomes
Extensor Zones of the Hand
Hint: odd-numbers = joints & even-numbers = bone.
- Zone 1: Distal Interphalangeal Joint (DIPJ)
- Zone 2: Middle Phalanx
- Zone 3: Proximal Interphalangeal Joint (PIPJ)
- Zone 4: Proximal Phalanx
- Zone 5: Metacarpophalangeal Joint (MCPJ)
- Zone 6: Metacarpals
- Zone 7: Wrist Joint
- Zone 8: Distal 1/3 of the arm.
- Zone 9: Proximal 2/3 of the arm.
These extensor (dorsal) zones of the hand are illustrated below.
The location of the extensor zones and their clinical significance can be seen in the table below. For example:
- Zone 3 injury often involves central slip & results in a Boutonniere Deformity.
- Patients with hand compartment syndrome will require incisions in zone 6.
Chief Contributor: Dr Harsh Shah
1. William R. Walsh. Repair and Regeneration of Ligaments, Tendons, and Joint Capsule. (2007) ISBN: 9781592599424
2. Donald Hugh Johnson. Practical Orthopaedic Sports Medicine and Arthroscopy. (2020) ISBN: 9781469878324
3. Kleinert HE, Verdan C. Report of the committee on tendon injuries. J Hand Surg. 1983;8:794.
4. Kotwal PP, Ansari MT. Zone 2 flexor tendon injuries: Venturing into the no man's land. (2012) Indian journal of orthopaedics. 46 (6): 608-15. doi:10.4103/0019-5413.104183 - Pubmed
5. Wilhelmi BJ, Snyder N, Verbesey JE, Ganchi PA, Lee WPA. Trigger finger release with hand surface landmark ratios: an anatomic and clinical study.Plast Reconstr Surg. 2001;108(4):908-915.