Extension tendon repair post-op rehabilitation
Mallet injury –
- Complete full time immobilization for 8 weeks.
Zone III injury (closed rupture of central slip)–
- Complete full time immobilization for 8 weeks.
Zone VIII & IX –
- Immobilization
Zone III – V –
- Immobilization protocols have greater chances of adhesions
- Limited early active motion protocol (given by Evans) – also called “Short arc motion” – reduces chances of adhesion.
- Three splints are used. One for rest and two for exercise.
At rest –
- Affected digit immobilized with wrist in extension and 0° extension of DIP & PIP
During exercise –
- Splint used – which blocks PIP flexion to 30° and DIP flexion to 20-25°.
- 20 repetitions of active and passive movement.
- Third splint is now used – which fixes PIP in 0° extension and allows only DIP movement.
- Patient now actively extends and flexes DIPJ x 20 times.
Exercise continued for 3 weeks. During 2nd and 3rd week – PIPJ flexion gradually increased to 40-50°.
Zone V-VIII –
- Passive extension by rubber band system with active flexion of the affected digits
- Protocol termed – Reverse Washington or Reverse-Kleinert.
Active flexion by patient and passive extension by rubber band – 10 times per hour for 3 weeks
Flexion of MP joint restricted first to 30° and then gradually increased to 60° at end of 3 weeks
Active motion initiated after 3 weeks
Splint removed after 6 weeks.
Short arc motion regimen based on –
- Short amount of tendon excursion prevents adhesion formation – a 3-5 mm tendon excursion is required to prevent adhesion
- A 60° PIPJ flexion achieves 5mm excursion.
- Earlier immobilization protocols were/are based on theory that –
- Extrasynovial nature of extensor tendon limits adhesion formation.
- Close proximity to bone and tissue in zone III – VIII increases chances of adhesion and are better rehabilitated with active motion protocol.
Relative motion splint –
- Relative tendon extensor splint – affected finger in 15-20° “extra” MCP extension than other fingers.
- Relative tendon flexor splint – affected finger in 15-20° “extra” MCP flexion than other fingers.
- Allows early active use of hand.
- Relative splinting gives rest to the tendon repair during motion as the extensor tendons are joined/conjoint and acts as one unit.