Outcome After Tibial Plateau Fracture: How Important Is Restoration of Articular Congruity?

OBJECTIVES

Does restoration of articular congruity have any effect on long-term outcome following tibial plateau fracture?

DESIGN

Cohort study.

SETTING

A secondary hospital in New Zealand, which services a population of 150,000.

PATIENTS

All patients with a depressed tibial plateau fracture seen over a 6 year period were invited to participate in the study. There were 41 patients (average age 54 years) recruited from an eligible population of 97. Average follow-up was 3.9 years after injury.

INTERVENTION

Patients had either been treated operatively or nonoperatively after depressed tibial plateau fracture.

MAIN OUTCOME MEASUREMENTS

The primary outcome analyzed was residual articular depression (as measured on coronal plane tomogram) and its effect on clinical outcome [Oxford Knee Score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, Knee injury and Osteoarthritis Outcome Score (KOOS), Iowa knee score, and a visual analogue satisfaction score] and functional outcome (knee range of motion) at a minimum of 12 months after fracture. Patients were divided into 3 groups based on the amount of articular depression: <2.5, 2.5-5.0, and ≥5.0 mm. The secondary outcome analyzed was mechanical axis (as measured on weightbearing long leg alignment radiographs) and its effect on clinical and functional outcomes.

RESULTS

Statistical analysis found that patients with <2.5 mm of articular depression had significantly smaller losses in knee range of motion (P = 0.000), better Oxford (P = 0.006), Iowa (P = 0.003), and KOOS symptom (P = 0.011) and pain (P = 0.001) scores. We found that there was no significant relationship between restoration of mechanical axis and loss in range of motion (P = 0.126), Oxford (P = 0.584), WOMAC (P = 0.101), IOWA (P = 0.418), Visual Analogue Score (VAS) (P = 0.466) or any subgroup within the KOOS survey other than activities of daily living (P = 0.029).

CONCLUSIONS

This study found that patients with smaller amounts of residual articular depression at a minimum of 12 months after tibial plateau fracture had significantly smaller losses in knee range of motion and better functional outcomes than those with greater amounts of articular depression.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.