Impacts of Fracture Types on Success Rate of Closed Reduction and Percutaneous Pinning in Pediatric Lateral Condyle Humerus Fractures Displaced >4 mm

Abstract

Background: Closed reduction and percutaneous pinning (CRPP) is a promising treatment for pediatric lateral condyle humerus fractures (LCHFs) displaced > 4 mm. However, few studies discussed roles of fracture types on success of CRPP in LCHFs. This study aimed to analyze the impacts of types of LCHFs displaced > 4 mm on the success rate of CRPP. Methods: We retrospectively reviewed 66 consecutive pediatric LCHFs attempted CRPP at our center. Song, Milch, Jakob, and Weiss classification were used to classify LCHFs. The fracture gap ≤ 2 mm and step of articular surface ≤ 2 mm were deemed as a successful CRPP. Otherwise, open reduction and internal fixation (ORIF) would be performed. Different fracture types and preoperative displacement were analyzed for their roles on success rate of CRPP in treating LCHFs displaced > 4 mm. Results: Fifty patients met the inclusion criteria were finally included in this study. Results showed that Milch type II LCHFs had a higher success rate of CRPP than type I LCHFs (P = 0.03, <0.05). Correlation was found between Milch types and success rate of CRPP displaced > 4 mm. No difference was found between Song stage 4 and 5 LCHFs displaced > 4 mm in success rate of CRPP (P = 0.90, > 0.05), also no difference was found in preoperative displacement between CRPP group and ORIF group. Conclusions: Milch classification is more important than Song classification in the success rate of CRPP when treating LCHFs displaced > 4 mm. Milch type II LCHFs are recommended to be treated with CRPP, while Milch type I LCHFs are recommended to be treated with ORIF. The current study confirm Song's initial report that closed reduction can be successful and should be attempted for fractures with such displacement rather than going directly to ORIF. Level of Evidence: Level III.

Commentary: A comparative study on closed reduction vs. open reduction: Techniques in the surgical treatment of rotated lateral condyle fractures of the distal humerus in children

“…Xie et al ( 5 ) reported an overall closed reduction and percutaneous pinning (CRPP) rate of 74% for LHCFs with >4 mm displacement. There was no difference in the CRPP rate between Song stage 4 (75%; 15 of 20 cases) and stage 5 cases (73%; 22 of 30 cases) but there was a significant difference between Milch type I (50%; 6 of 12 cases) and II (82%; 31 of 38 cases) fractures.…”

“…Information on the length of the individual procedures was not provided. Xie et al ( 5 ) concluded that a closed reduction should always be attempted and that the fracture anatomy, as identified by the Milch classification, is more important for the success rate than the Song classification. We would like to ask Weng et al if they could identify the Milch types for their fractures and if there was an association between Milch type I and increased ORPP rate?…”

Impacts of Fracture Types on Success Rate of Closed Reduction and Percutaneous Pinning in Pediatric Lateral Condyle Humerus Fractures Displaced >4 mm

“…We read with interest the recent publication by Xie and colleagues 1. Xi et al2 already published data from the same patients in 2021 but stated in their current publication1 that all 50 fractures were a Jakob type III, which is equivalent to a Song stage 5 (displaced and rotated fragment) 1,3. We would like to ask the authors how they explain the inconsistency of them having reported that only 30 of 50 fractures were a Song type 51 and what the Song type 5 rate was for each Milch type group, since malrotation might be a contributing factor to the failed closed reduction rate?…”

“…In conclusion, we think that there is a need for a lateral condyle fracture classification which considers the anatomy, displacement, and malrotation. Xi et al’s1,2 fair Flynn outcomes with mean loss of flexion of 12.9 degrees for their closed and failed closed reduction groups and 13.3 degrees for their primary open reduction group indicates a possible need for the authors to reassess and change their management strategy. Areas we are concerned about because of a potential negative impact on functional recovery are: accuracy of intraoperative arthrogram assessment of post-reduction displacement, acceptance of an articular step of up to 2 mm, the use of 3 or 4 wires (all of Xi et al’s1,2 depicted fixations) in these small children (mean age 5.6 y) which increases potential damage to the soft tissues and growth plate, and leaves wires in place for a mean of >15 weeks following open reduction 2…”

“…We would like to ask the authors how they explain the inconsistency of them having reported that only 30 of 50 fractures were a Song type 51 and what the Song type 5 rate was for each Milch type group, since malrotation might be a contributing factor to the failed closed reduction rate? We also would like to ask Xie et al1 why they compared the Milch with the Song3 classification, despite the latter not considering Milch type I fracture patterns, which are the result of abduction forces and Song et al4 themselves having abandoned their own classification already in 2010, when the authors used the Jakob classification without referencing their own classification, indicating that the Song classification is deficient and not adequate to classify the spectrum of lateral condyle fractures.…”