What is the treatment for a partial laceration of a flexor tendon?

Treatment for Partial Laceration of Flexor Tendon

For partial flexor tendon lacerations, the recommended treatment is non-surgical management with early mobilization for lacerations involving less than 50-60% of the tendon cross-section, while surgical repair is indicated for lacerations greater than 60% to prevent complications such as entrapment, rupture, or triggering.

Diagnostic Assessment

Before determining treatment, accurate assessment of the laceration extent is crucial:

• MRI is the preferred imaging modality for evaluating tendon injuries with high sensitivity and specificity for flexor tendon injuries 1
• Ultrasonography can be used to identify high-grade partial flexor tendon lacerations (>60%) but tends to underestimate the percentage of tendon involvement by approximately 18% 2
• Dynamic ultrasound allows direct visualization of tendon integrity during movement 1

Treatment Algorithm Based on Laceration Severity

1. Partial Lacerations <50-60% of Tendon Cross-Section:

• Non-surgical management with early controlled mobilization 3
  • Early mobilization promotes optimal healing and prevents adhesions
  • No suturing of the tendon is required
  • This approach has shown excellent functional outcomes in 16 out of 17 patients with partial lacerations ranging from 25-95% 3

2. Partial Lacerations >60% of Tendon Cross-Section:

• Surgical repair is indicated 2
  • Primary repair with appropriate suture technique
  • Early controlled mobilization protocol following repair
  • Consider referral to a hand specialist for optimal surgical management

3. Complete Lacerations:

• Immediate surgical repair is required
• In chronic cases where direct repair is not possible, tendon grafting may be necessary using intrasynovial tendon grafts 4

Rehabilitation Protocol

Following either non-surgical management or surgical repair:

1. Initial Phase (0-4 weeks):

   • Pain control
   • Protected range of motion exercises
   • Avoid overuse of the injured area for 24 hours post-treatment 5

2. Intermediate Phase (4-8 weeks):

   • Progressive strengthening exercises
   • Eccentric training 5

3. Advanced Phase (8-12 weeks):

   • Occupation-specific training
   • Functional exercises 5

Potential Complications

Be vigilant for these complications in untreated partial lacerations:

1. Entrapment: Tendon flaps may become entrapped in the flexor tendon sheath
2. Rupture: Delayed rupture can occur when force is applied to the partially lacerated tendon
3. Triggering: Abnormal tendon movement through the pulley system 6

Follow-up Assessment

• Regular assessment at 2,6, and 12 weeks to evaluate:

  • Pain levels
  • Range of motion
  • Functional improvement
  • Signs of complications 5

• Consider surgical intervention if no improvement occurs after 3-6 months of well-managed conservative treatment 5

Return to Activity Criteria

Return to full activity is permitted when the patient demonstrates:

• Complete resolution of pain
• Full range of motion
• Strength symmetry >90% compared to the uninjured side
• Successful completion of occupation-specific functional tests 5

This evidence-based approach balances the risks of surgical intervention against the potential complications of untreated partial tendon lacerations, with treatment decisions primarily guided by the extent of tendon involvement.