Internal fixation of undisplaced femoral neck fractures in the elderly: A retrospective comparison of fixation methods

BACKGROUND: There has been no report related to comparison of fixation methods using minimally invasive dynamic hip screw (MIDHS), conventional dynamic hip screw (CDHS), and multiple cannulated screws (MCS) for treating the undisplaced femoral neck fractures. METHODS: The study retrospectively evaluates the comparison of fixation methods. Ninety elderly patients (>60 years) with the undisplaced intracapsular femoral neck fractures were treated with osteosynthesis by either dynamic hip screw (DHS) or MCS. The patient distribution was regarded as randomized. A new minimally invasive technique of DHS (MIDHS) was presented. Pauwels' classification was used to evaluate the fracture verticality. Singh index was used to evaluate the bone quality. All patients were followed up retrospectively for at least 12 months to compare the clinical results among the MIDHS, CDHS, and MCS groups. RESULTS: Pauwels types and Singh index were similar among the three groups (all p values ≥0.78). The CDHS group had significantly larger wound incision, greater hemoglobin level drop, and longer hospital stay than either the MIDHS or MCS groups (all p values ≤0.014). Differences in hip score, incision length, surgery time, hemoglobin level drop, and hospital stay between the MIDHS and MCS groups were not significant (all p values ≥0.28). The MIDHS group showed a trend of an increased rate of overall success compared with the MCS group, although this was not statistically significant (97% vs. 84.4%, p = 0.11). CONCLUSION: CDHS had more disadvantages related to more soft tissue stripping than either MIDHS or MCS. MIDHS showed a trend of an increased rate of overall success in an elderly patient with undisplaced femoral neck fracture when compared with MCS.