[Effectiveness of extended Carlson approach in treatment of lateral femoral condylar Hoffa fractures].

Objective: To investigate the effectiveness of the extended Carlson approach in the treatment of lateral femoral condylar Hoffa fractures.

Methods: The clinical data of 17 patients with lateral femoral condyle Hoffa fractures between September 2012 and January 2019 were retrospectively analyzed. There were 10 males and 7 females, with a mean age of 43 years (range, 32-68 years). Fractures were caused by traffic accident in 9 cases, by falling from height in 6 cases, and by the other mechanism in 2 cases. According to the Letenneur's classification, there were 8 cases of typeⅠ, 6 cases of type Ⅱ, and 3 cases of type Ⅲ. The mean time from injury to operation was 7 days (range, 3-32 days). All patients were treated with extended Carlson approach. Patients with Letenneur types Ⅰ and Ⅲ were fixed by a posterior antigliding plate combined with headless compression screws from anteroposterior direction, and patients with Letenneur typeⅡ were fixed by headless compression screws from anteroposterior direction. The anteroposterior and lateral X-ray films, CT and three-dimensional reconstruction of the knee joint were taken after operation to assess fracture healing and position of the internal fixators. The knee function was evaluated according to Letenneur's functional assessment system.

Results: All patients were followed up 13-28 months (mean, 15 months). All the incisions healed by first intention, and no complication such as fracture redisplacement, fracture nonunion, internal fixator fracture, and common peroneal nerve injury occurred. The mean time of fracture healing was 18 weeks (range, 16-32 weeks). At last follow-up, according to Letenneur's functional assessment system, the knee function was excellent in 12 cases and good in 5 cases, with an excellent and good rate of 100%.

Conclusion: The extended Carlson approach for the treatment of lateral femoral condylar Hoffa fractures has the advantages of clear exposure, easy reduction and fixation, high fracture healing rate, few complications, and good recovery of knee joint function.