Open reduction and internal fixation of irreducible displaced femoral neck fracture with femoral Neck System: a preliminary study

Background Most displaced femoral neck fractures can achieve satisfactory anatomical reduction by closed reduction, but there are still some that cannot reset satisfactorily after closed reduction, and open reduction are required. Such fractures that cannot be repositioned successfully by closed reduction are called irreducible displaced femoral neck fractures in this study. The objective of our study was to evaluate the efficacy of direct anterior incision with the Femoral Neck System in the treatment of irreducible displaced femoral fractures.Methods A total of 16 young and middle-aged patients with irreducible displaced femoral neck fractures involving Garden type III and IV were treated using Femoral Neck System fixation by open reduction through Direct Anterior Approach between January 2020 to September 2021. Functional outcomes and postoperative complications were assessed during follow-up. Clinical outcomes were evaluated by the Hip Harris score. The postoperative reduction was evaluated by the Garden Index. Observe postoperative complications.Results All patients were followed up with a mean follow-up time of 21.1(12-30) months, and according to radiological results, all patients achieved fracture healing, with a mean healing time of 4.25 months. All 16 patients received grade Garden I and II reductions, and there was no significant difference in the anteroposterior Garden reduction index between the first day after surgery (166.13 +/- 5.61) and the 12th month after surgery(164.94 +/- 4.49) (P>0.05) and no significant difference in lateral Garden index between the first day after surgery(171.06 +/- 4.46) and the 12th month after surgery(169.38 +/- 3.98) (P<0.05). According to the Hip Harris score scale, 13 patients received excellent and 3 patients received good. The postoperative Hip Harris Score(17.19 +/- 4.8) was significantly higher than the preoperative score(92.19 +/- 3.4), and the difference was statistically significant (P < 0.05). No or mild femoral neck shortness occurred in 12 (75%) patients, moderate shortening occurred in 3 (18.75%) patients, and severe shortening occurred in 1 (6.25%) patient. None of the patients experienced femoral head necrosis, fracture nonunion, or incision infection. One patient developed deep venous thrombosis of the lower extremity.Conclusions The Direct Anterior Approach combined with Femoral Neck System is an excellent treatment for irreducible displaced femoral neck fracture and achieved good functional outcomes and anatomical reduction with low complications.