BACKGROUND:
Anterior knee pain is the most common complication after intramedullary nailing of the tibia. Dissection of the patellar tendon and its sheath during transtendinous nailing is thought to be a contributing cause of chronic anterior knee pain. The purpose of this long-term follow-up of a prospective, randomized study was to assess whether the prevalence and intensity of anterior knee pain after intramedullary nailing of a tibial shaft fracture is different in transtendinous versus paratendinous incision technique.

METHODS:
Fifty patients with a tibial shaft fracture requiring intramedullary nailing were randomized equally (25 plus 25) to treatment with paratendinous or transtendinous nailing. Forty-two patients (21 plus 21) were reexamined an average of 3 years after nailing, whereas 28 patients (14 plus 14) could be now reexamined an average of 8 years after the nailing. As in the first reexamination, the patients at the 8-year follow-up used visual analog scales to report the level of anterior knee pain and the impairment caused by the pain. The scales described by Lysholm and Gillquist and by Tegner et al., the Iowa knee scoring system, and simple functional tests were used to quantitate the functional results. Isokinetic thigh-muscle strength was also measured.

RESULTS:
Four (29%) of the 14 patients treated with transtendinous nailing reported anterior knee pain at the 8-year follow-up evaluation. The number was the same for patients treated with paratendinous nailing. The Lysholm, Tegner, and Iowa knee scoring systems, the muscle-strength measurements, and the functional tests showed no significant differences between the two groups.

CONCLUSION:
Compared with a transpatellar tendon approach, a paratendinous approach for nail insertion does not reduce the prevalence of chronic anterior knee pain or functional impairment after intramedullary nailing of a tibial shaft fracture. In long term, anterior knee pain seems to disappear from many patients.