Surgical treatment of supracondylar fractures in children: should the pins be buried or left exposed? Comparative study of functional and radiographic results of two surgical protocols

Introduction

The osteosynthesis of supracondylar fractures (SC) using pins buried under the skin (PB) or externalized (PE) is a subject of debate. The aim of this study was to compare two treatment protocols, one using PB and the other using PE, in terms of clinical and radiographic outcomes, complication rates.

Hypothesis

The hypothesis of the study was that both protocols are equivalent in terms of clinical, radiological outcomes, and complication rates.

Materials and methods

This was a retrospective bicentric comparative study analyzing 296 boys and 267 girls (mean age 6.2 ± 2.7 years) who underwent SC fracture surgery between 1/1/2010 and 31/12/2020 using two therapeutic protocols. The first protocol (group A; n = 210) involved osteosynthesis with PB, immobilization (6–7 weeks), and pin removal in the operating room under general anesthesia. The second protocol (group B; n = 353) was characterized by osteosynthesis with PE, immobilization (4–6 weeks), and pin removal in an outpatient setting. Functional outcomes were assessed using the QuickDASH questionnaire, radiographic outcomes [Baumann angle, lateral capitulum-humeral angle (LCHA), rotational disorders according to the Von Laer quotient], and postoperative complication rates (infection, recurrent fracture, stiffness, vasculo-nerve complications).

Results

No patients were lost to follow-up (n = 563) and the mean follow-up was 6.6 ± 7.3 months (3–70). The mean immobilization duration was longer in group A (45.8 ± 7.4 vs 39.7 ± 12.0 days; p < 0.001). Clinical and functional outcomes were similar (p = 0.316), and the pre- and postoperative complication rates were comparable between the two groups (A-B = 8 %/8.6 %-6 %/7.1 %; p = 0.733 and p = 0.512), while the postoperative Baumann angle, LCHA, number of rotational disorders, and Von Laer quotient were significantly different [A-B = 71.5°-74° (p < 0.001); A-B = 32.8°-35.6° (p < 0.001); A-B = 32–10 (p < 0.001); A-B = 0.2–0.1 (p = 0.020)].

Discussion

This retrospective study compared two surgical protocols for pediatric supracondylar (SC) fractures in 563 children. Functional and clinical outcomes were similar between groups, with no significant difference in complication rates. Group B had better radiographic results and a lower rate of postoperative rotational deformities. Pin buried (Group A) increased costs and required a second general anesthesia for removal. Group B's protocol allowed outpatient pin removal under nitrous oxide, reducing risks and costs. Infection rates were no significant different between both groups. Whereas the decrease of number of rotational disorsders, the increase of Baumann angle and decrease of LCHA in this patient show that decrease of rotational disorders is more likely related to osteolysis of rotational spur than bone remodeling. Despite limitations, this is the largest French series comparing these two protocols, showing equivalent functional outcomes but greater efficiency and safety in Group B.

Conclusion

Both therapeutic protocols have comparable clinical outcomes and complication rates. Leaving pins exposed does not increase the risk of infection.

Level of evidence

III comparative retrospective study