The prevalence of knee injuries ipsilateral to tibial shaft fractures and their impact on clinical outcome.

OBJECTIVE

The purpose of this prospective study was to examine the prevalence of occult knee injuries in patients with ipsilateral tibial shaft fractures and determine their impact on clinical outcome.

MATERIALS AND METHODS

Preoperative knee MRI examination was performed in 41 patients (42 knees) with isolated tibial shaft fractures. Menisci, cruciate ligaments, collateral ligaments, extensor mechanism, osteochondral lesions, bone contusions and knee effusion were evaluated. All patients were treated with reamed and locked intra-medullary tibial nailing without an additional surgical procedure for knee injuries. All patients were followed to at least fracture union and were evaluated with knee examination and Lysholm knee score.

RESULTS

Of the 42 knees, 41 (97.6 %) showed at least one defined injury around the knee. There was only one patient who had totally normal knee MRI findings. One or more ligamentous injuries of the knee were identified in 35 (83.3 %) of the knees. Five patents (11.9 %) had medial meniscal tear in posterior horn. Extensor mechanism injuries were seen in two patients. Mild to marked joint effusion was observed in 35 (81 %) knees. Twenty-two knees demonstrated bone bruise; femoral condyle (n = 7), tibial plateau (n = 12), patella (n = 2) and fibular head (n = 1). No patients had osteochondral lesion. Patients were followed with a mean of 13.2 ± 3.6 (range 8-22) months. Clinical knee examination revealed Grade II (+) anterior drawer test in two patients. The mean Lysholm knee score was 99.1 ± 2.14 (range 91-100) at the final follow-up.

CONCLUSIONS

Ipsilateral intra-articular, extra-articular or combined knee injuries may occur at the time of injury with tibial shaft fractures. However, most of these injuries are not clinically relevant and heal without any sequel or remain asymptomatic late after fracture union. Routine use of preoperative knee MRI examination in patients with tibial shaft fractures is not necessary.