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.
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.
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.
Clinical relevance
Zone 1
Distal interphalang joint (DIP)
Mallet injury: Mallet finger is an injury to the thin tendon that straightens the end joint of a finger or thumb. This joint is called the distal interphalangeal (DIP) joint in the fingers and the interphalangeal (IP) joint in the thumb.
The injury can happen when an unyielding (rigid or solid) object (like a baseball) strikes the tip of a finger or thumb and forces it to bend further than it is intended to go
Zone 2 Middle phalanx
Central slip insertion: Extensor injuries of the hand are common in young, otherwise healthy males.[1] Various injury mechanisms include hyperflexion, direct blunt trauma and penetrating trauma.
Zone 3 proximal interphangeal joint
Boutonniere deformity: A boutonnière deformity can affect the index, middle, ring, and little fingers. It is often the result of an injury to the tendon that straightens the middle joint (the proximal interphalangeal, or PIP joint) of the finger. This can occur:
Due to trauma, such as a laceration or a dislocation
Because of damage to soft tissue caused by a rheumatologic condition such as rheumatoid arthritis
Zone4 proximal phalanx
(Can involve central slip and lateral bands) describe above central slip
Zone 5 Metacarpophalangeal joint
Can involve saggital joint and joint capsule
Ulnar collateral ligament injury : The ulnar collateral ligament of the thumb (first metacarpophalangeal joint) is frequently injured in sporting pursuits, leading to pain and instability in the thumb
Zone 6 Metacarpals
Distal to junctura ( Tendon can retract)
Zone 7 wrist joint
Involvement of extensor retinaculum
By extending fascial attachments to the underlying bones and periosteum, the retinaculum forms six osseofascial compartments over the dorsal wrist.
Zone 8 Distal 1/3 of forearm
Can involve musculotendinous junction
Zone 9 proximal 2/3 of forearm
Involve muscles belly
Physiotherapy management
The ultimate aim of any rehabilitation is to obtain healing with minimal gapping and prevent adhesions. Static mobilisation was the traditional method of postoperative rehabilitation but complications including tendon rupture, adhesion formation requiring tenolysis, extension lad, loss of flexion and decreased grip strength have all been documented
Early mobilisation rehabilitation programmes can be in two categories
(1) early active mobilisation
(2) early controlled mobilization using a dynamic splint.
Early controlled motion with a dynamic extensor splint has been found to decrease adhesions and subsequent contractures. Only two randomized controlled trial studies have compared early mobilisation versus early active mobilisa
3) Manual therapy with Active release technique and muscle energy techniques to make muscles quality improvement and increase blood circulation and ultimately helps to heal .
4) Electro modalities ( Tens Ift and ust ),
Helps to reduce pain on the working mechanism of pain gate theory.
5) Laser therapy helps to heal the muscles and also help to improve joint mobility