Anterior knee pain after tibial intramedullary nailing using a medial paratendinous approach.

OBJECTIVES

To determine the incidence, severity, and etiology of anterior knee pain after tibial intramedullary (IM) nailing using a medial paratendinous approach and to investigate the association between anterior knee pain and functional impairment.

DESIGN

Retrospective study with current clinical and radiographic assessments.

SETTING

Level I trauma center.

PATIENTS: Forty-five patients with unilateral, tibial diaphyseal fractures treated with tibial IM nailing between August 2005 and January 2009. The mean follow-up was 22.3 months (range, 12-52 months).

INTERVENTION: All patients underwent tibial IM nailing using a medial paratendinous approach.

MAIN OUTCOME MEASUREMENTS: Anterior knee pain based on a visual analog scale and functional outcomes based on the Tegner activity score and the modified Lysholm score.

RESULTS

Of the 45 patients, 16 (36%) were painless (N group), 16 (36%) had mild pain (M group), and 13 (28%) had moderate to severe pain (MS group). No group differences were found with respect to age, sex, body mass index, mode of injury, or type of fracture. With regard to nail prominence, superior nail prominence was greater in the MS group than in the other two groups (P = 0.042). There were no significant differences among the three groups in terms of anterior nail prominence (P = 0.221). The nail-apex distance in the MS group was significantly greater than in the other two groups (P = 0.033), and no significant difference was found between the N and M groups. The descending order of the activities with respect to severity of knee pain was kneeling, squatting, running, and stair ascending. Visual analog scale analysis revealed that the MS group had significantly more severe pain for all eight activities examined than the M group. At latest follow-up, the Tegner activity score was significantly lower in the MS group than in the other two groups (P = 0.008), and there were statistically significant intergroup differences in the modified Lysholm score (P < 0.001).

CONCLUSION

Anterior knee pain after tibial IM nailing using a medial paratendinous approach was a frequent complication that was not uncommonly moderate to severe (28%) in Asian patients. Although the etiology of anterior knee pain is undoubtedly multifactorial, it may be related to nail prominence. Furthermore, the severity of anterior knee pain was significantly associated with functional outcome.

LEVEL OF EVIDENCE: Therapeutic Level IV. See page 128 for a complete description of levels of evidence.