Critical-sized defect in the tibia: is it critical? Results from the SPRINT trial

Area of Science:

• Orthopedic surgery
• Trauma care
• Bone healing research

Background:

• The SPRINT trial defined critical-sized defects in tibial fractures as gaps >= 1 cm and >50% cortical involvement.
• The clinical significance and healing potential of these defects require further investigation.

Purpose of the Study:

• To validate the SPRINT definition of a critical-sized tibial defect.
• To identify predictors of reoperation in patients with these defects.
• To compare patient-based outcomes between critical-sized defects and non-critical defects.

Main Methods:

• Therapeutic cohort study conducted at Level 1 and 2 trauma centers.
• Evaluated 37 patients with critical-sized defects from the SPRINT trial for secondary interventions.
• Compared outcomes and characteristics with a larger cohort of patients without critical defects.

Main Results:

• 47% of critical-sized tibial defects healed without additional surgery.
• Reamed nailing and female sex were associated with lower reoperation rates.
• Critical defects were linked to high-energy mechanisms, AO-OTA types 42B/C, and middle-third tibial location.
• Patients with critical defects had significantly worse 12-month SF-36 physical component scores.

Conclusions:

• The SPRINT definition of a critical-sized tibial defect is not absolute, as many heal spontaneously.
• Patients with these defects experience higher reoperation rates and poorer functional outcomes compared to those without.
• Further research is needed to identify predictive factors for union in critical-sized defects to optimize treatment and avoid unnecessary surgeries.