Correlation between Post-Operation Center-Trochanteric Distance (CTD) and Tip Apex Distance (TAD) changes in Intertrochanteric Fractures Treated by Dynamic Hip Screw

One of the most common injuries and an important cause of mortality and morbidity in the elderly is intertrochanteric fracture. The dynamic hip screw (DHS) is one of the best procedures for fixation of these fractures; however, using DHS is accompanied by failure risk. Therefore, with the purpose of reducing failure risk, this study aimed to evaluate the correlation between post-operation CTD and TAD, NSA changes in patients with intertrochanteric fractures. In this case series study, patients with intertrochanteric fracture treated with DHS between September 2015 and January 2016 were included. The exclusion criteria were pathologic fracture, multiple fractures, greater trochanter fracture, soft-tissue issues, A3OTA type, patients who missed the follow-up period, history of previous hip fracture or dislocation, and TAD>25mm. Ultimately, 24 patients were included in this study. Two surgeons reviewed the anteroposterior (AP) and lateral (Lat) radiographs. The measures of TAD, CTD, and NSA after six-months of follow-up were assessed. In addition, variables such as demographic data, fracture side, duration of operation, blood loss volume, weight bearing day, and Harris hip score (HHS) were analyzed. The relationship between post-operation CTD and TAD, NSA changes after six months of follow-up was analyzed. All data was analyzed using SPSS 20 software (SPSS, IBM Inc., USA). The significance level for all tests was considered to be 0.05. This study evaluated 24 patients. The mean age of the patients was 69.9 ± 12.00 years, and 15 (62.5%) of them were male. No significant correlations were seen in the collected data, especially CTD and NSA changes after six-months of follow-up (p>0.05). Maximum and minimum TAD values after surgery were 25.6 and 11.0, respectively. Maximum and minimum TAD values at the six-month follow-up were 34.9 and 11.0, respectively. Mean TAD was constant at 19.8±5.3 in postoperative and follow-up measurements. This shows that patients experienced increases in TAD and others experienced decreases in TAD within the six months of follow-up. The results showed that despite the abnormal CTD after surgery, the risk of TAD changes increased. Generally, TAD is a well-established radiographic measurement for predicting the risk of cut-out. CTD and TAD can be used together or separately to predict the risk of DHS screw cut-out in patients with intertrochanteric fractures in future studies.