The treatment of femoral neck fracture in young patients still faces many challenges due to adverse clinical outcomes. In a survey of 540 orthopedic surgeons, 78% of surgeons prefer to use multiple cannulated screws to treat nondisplaced femoral neck fracture. For displaced fractures, multiple screws (46%) and sliding hip screws (SHS, 49%) were first taken into consideration for the majority of orthopedic surgeons .
The surgical approach includes open or closed reduction with internal fixation. Ghayoumi et al.  found no difference in nonunion or AVN rates in their meta-analysis of the literature when comparing open versus closed reduction techniques. Most of the studies were reported higher rates of avascular necrosis, premature epiphyseal fusion, and heterotopic ossifications after open reduction. Otherwise, the closed reduction has the advantages of less trauma, less intraoperative bleeding, and shorter operation time, theoretically reduced the risk of postoperative surgical complications . Consequently, closed reduction and internal fixation of fracture is the preferred method of treatment. In this study, all patients underwent Gotfried reduction (closed reduction) and cannulated screws fixation.
For younger patients (under 65 years), anatomical reduction, rigid fixation, and preservation of their hip joints are the primary treatment goals, especially to those who have an abundance of daily activities [6, 7, 9, 14]. There is a large body of literature repeatedly emphasized the importance of anatomical reduction. It has been regarded as a key to effective treatment [6, 10, 15]. Although achieving anatomical reduction is the goal of treating femoral neck fractures, it does not guarantee a good prognosis. It probably requires repeated manipulations to achieve anatomical reduction but instead appears to increase the odds of avascular necrosis and fracture nonunion .
The anatomical reduction was never challenged; however, Gotfried et al. believe that anatomical reduction is not strictly necessary . The anatomical reduction may not promote fracture healing and reduce the occurrence of femoral head avascular necrosis . In a group of young patients, there is a good reduction in postoperative radiography. However, nonunion occurred in 8%, 11.5% of avascular necrosis of the femoral head . Gotfried et al. proposed the concept of “non-anatomical reduction of femoral neck fractures” and expounded the following concepts in his literature: (1) positive buttress position a displaced subcapital femoral position, anteroposterior (AP) view, in which the distal femoral neck fragment is positioned medially to the lower-medial edge of the proximal fracture fragment; (2) negative buttress position a displaced subcapital femoral position, (AP) view, in which the proximal fracture fragment (femoral neck and head) is displaced medially to the upper medial edge of the distal femoral neck fragment. (3) Negative buttress position is highly correlated with failure of reduction.
Although Gotfried reduction method was first applied to subcapitated femoral neck fractures, the concept of positive buttress is not limited to this type of fractures. This study included both subcapital, transcervical, and basicervical fracture types. The results showed that the incidence of postoperative neck shortening and Harris score of the hip joint in the positive support reduction group were significantly better than those in the negative support reduction group.
Interestingly, in this study, we found that non-anatomical reduction with Gotfried positive buttress may lead to similar clinical results with anatomic reduction. The Harris scores and neck shorting in group A (anatomical reduction) was not statistically different from group B (positive buttress reduction). Nevertheless, the first two groups are statistically better than group C (negative buttress reduction). So, the patients’ good postoperative function may be related to the advantages of positive buttress reduction in preventing neck shortening.
Parallel cannulated screws fixation is sometimes associated with a risk of femoral neck shortening. The varus and shortening of the femoral neck negatively correlate with Harris hip scores, as reported in the literature. Patients with severe shortening of the femoral neck had significantly lower short (SF-36) physical functioning scores. Shortening also resulted in a significantly lower EuroQol questionnaire (EQ 5D) index score [3, 13].
The benefits of positive buttress may come from the special anatomy of the proximal femur. The direction of forces reflects the development of the femoral neck’s trabecular lines, which increased bone mineral density to specific areas of the hip. Ward’s area, or Ward’s triangle as initially called, is the space localized at the femoral neck formed by the intersection of three trabecular bundles, namely, the principal compressive, the secondary compressive, and the tensile trabeculae, an arched structure is formed on the medial side of the femoral neck . Adam’s arch plays an essential role in sustaining the stability of the femoral neck. The neck resides in an arch of compact tissue, which begins small where the globular head joins the under part of the neck, but which gradually enlarges downwards toward the lesser for the stability of the proximal femur . When the positive buttress is reached, the sliding pressure of the femoral head forms an insertion. The distal of cortex supports the proximal of the medial femoral neck. The special stress of the arch structure can effectively resist the longitudinal shear force between the fractured pieces and stabilize the fracture.
The limitations of this study are similar to those of all retrospective study designs. The retrospective study and the limited follow-up may lead to significant selection bias. Furthermore, this study is limited by the small number of case series. Besides, all types of fractures were included in the study. Theoretically, vertical femoral neck fractures have a higher failure rate than other types, which may influence the final result.
We would like to recommend this procedure as an available method of closed reduction before attempting open reduction. This procedure is used to treat irreducible femoral neck fractures encountered in our trauma center as part of routine procedures, and long term follow-up for the functional outcome will be obtained to confirm the therapeutic effectiveness of this procedure further.