Risk factors for cut-outs in geriatric intertrochanteric fractures with cephalomedullary nailing after obtaining acceptable reduction: a case-control study

The role of postoperative piriformis fossa and greater trochanter tubercle distance to predict cutout failure after cephalomedullary nail fixation

BACKGROUND

This study investigated the association between postoperative piriformis fossa and greater trochanter tubercle distance (distance from the deepest point of piriformis fossa to the most lateral greater trochanter tubercle [PG]) and cutout failure after cephalomedullary nail (CMN) osteosynthesis for intertrochanter fracture (ITF). A rotating femur model was designed to analyze PG variation during femur rotation.

METHODS

From 2005 to 2010, 311 patients diagnosed of ITF (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association [AO/OTA] 31-A2 and A3) underwent CMN fixation at our institute were reviewed. Of these, 281 (90.3%) patients achieved union without complication, 21 (6.8%) had cutout failure, six (1.9%) had femoral head osteonecrosis, and three (1%) had nonunion during postoperative 2-year follow-up. The side difference of postoperative PG compared to contralateral uninjured hip (dPG) was analyzed between patients who had cutout failure and those who did not. In the rotating femur model, the PG was measured for every 2.5° increments of internal and external rotation from 0° to 50°.

RESULTS

The dPG was significantly higher in the failure group (10.2 ± 4.2 vs 6.6 ± 3.5 mm, p <0.001). The odds ratio for lag screw cutout was 6.35 (95% CI, 1.10-11.6, p =0.003) for every 1 mm dPG increment. dPG exhibited high diagnostic performance in predicting cutout failure according to receiver operating characteristic curve analysis. The area under the curve was 0.774 (95% CI, 0.711-0.837). dPG yielded the greatest sensitivity (78.4%) and specificity (78.4%) to predict lag screw cutout when cutoff value being 8.65 mm. In rotating femur model, PG change from baseline demonstrated significant ( p <0.001) positive and negative correlation with increased external and internal rotation, respectively.

CONCLUSION

Increased dPG is a risk factor of cutout failure for ITF osteosynthesis with CMN. In conjunction with tip-apex distance, fracture displacement, and reduction quality; dPG can help surgeons interpret postoperative radiograph and predict failure. However, it should be noticed that a proper and standard patient positioning is critical for accurate dPG measurement.

Trochanteric fractures: Tip-Apex distance, Calcar Tip-Apex distance, and Chang criteria-a multiple variable analysis

Failure of osteosynthesis is a common complication of the nailing of trochanteric fractures which typically occurs through form of cut-out. Tip-Apex distance (TAD), Calcar Tip-Apex distance (CalTAD), and Chang criteria are validated variables to predict failure of cephalomedullary nailing. This is a retrospective study which analyzes treatment of trochanteric fractures from 2018 to 2020 (n = 296) evaluating postoperative radiographs and factors of mechanical failure. Our objective was to assess correlation among these variables and their influence on mechanical failure, either individually or creating a new score. Our results support the CalTAD and Chang's criteria as valid predictors of mechanical failure. Furthermore, they empathize the importance of fracture reduction and proper placement of cervical screw. To our knowledge, this is the first study performing multivariate analysis including these 3 variables.

Reduction quality in lateral view of X-ray and hypoalbuminemia are associated with postoperative mortality in elderly pertrochanteric fracture patients

Background

Pertrochanteric fracture is one of the most prevalent public health issues across the world for the elderly population. The purpose of this study was to investigate the association between surgical factors and postoperative mortality in patients with intramedullary nail-treated pertrochanteric fractures.

Methods

A retrospective cohort study was designed to evaluate the pertrochanteric fracture patients treated with intramedullary nail between January 2016 to February 2021. The surgical factors included the Dorr morphology, Arbeitsgemeinschaft für Osteosynthesefragen/Orthopedic Trauma Association (AO/OTA) classification of fractures, the tip-apex distance (TAD), location of the cephalic screw, reduction quality in anterior-posterior (AP) and lateral views, the integrity of the lateral wall, and the design of cephalic screws. Using univariate and multivariate Cox proportional hazard models, the association between these risk factors and postoperative mortality in patients with this type of fractures was evaluated.

Results

A total of 169 pertrochanteric fracture patients treated with intramedullary nails were included in our study, with the average age of 82.68±5.93 years. The mortality rates at 3 months, 1 year, and the end of follow-up were 4.14%, 11.24%, and 26.04%, respectively. According to the univariate Cox analysis, age, gender, preoperative levels of hemoglobin (Hb) and albumin (Alb) were associated with a poor overall survival (OS) (P<0.05). After multivariate adjustment, the pre-operative level of Alb (P<0.001) and the reduction in lateral view (P<0.001) were shown to be independent risk factors for poor OS.

Conclusions

The preoperative hypoalbuminemia and reduction quality in lateral view were associated with postoperative mortality in our study. Therefore, optimizing both parameters could improve the prognosis in elderly pertrochanteric fracture patients.

[Research progress on evaluation methods for head-neck nail position in femoral intertrochanteric fractures]

Objective

To summarize the research progress on the evaluation methods of head-neck nail positions in femoral intertrochanteric fractures.

Methods

The literature about the evaluation methods of head-neck nail positions for femoral intertrochanteric fractures in recent years was extensively reviewed, and research progress in the aspects of evaluation methods, clinical applications, and limitations were summarized.

Results

The position of head-neck nails in femoral intertrochanteric fractures is closely related to postoperative complications of head-neck nail cutting. Currently, the tip-apex distance (TAD) and femoral head zoning are widely used to evaluate the position of head-neck nails. The main opinion in the literature is that the use of TAD and femoral head zoning can effectively reduce the incidence of head-neck nails cutting. Parker's ratio, as one of the evaluation methods, has been controversial in subsequent studies and has not been widely used in clinical practice. The TAD as referenced to the calcar (CalTAD), which was modified based on TAD, has been gradually accepted by the clinic, but whether it is better than the TAD has not yet been conclusively determined. In recent years, new evaluation methods have been proposed to supplement the previous evaluation methods, such as the tip-neck distance ratio (TNDR) and the standardized TAD (STAD) to avoid the limitations of the TAD and the CalTAD by the volume of the femoral head, and the axis-blade angle (ABA) to supplement the direction of the head-neck nails channel, but at present the clinical application is relatively underutilized, and the validity of the method needs to be further verified.

Conclusion

Currently, there are many methods for evaluating the position of head-neck nails in femoral intertrochanteric fractures, TAD<25 mm combined with head-neck nails placed in the middle-middle quadrant or lower-middle quadrant of the femoral head division is currently a highly recognized assessment in the literature, but the optimal assessment is still controversial, and further research needs to be studied.

Eccentric distance zone analysis system: New regional evaluation of cephalic fixator tip location for predicting cut-out in geriatric intertrochanteric fractures with internal fixation

Objective

The aim of this study was to investigate an eccentric distance (ED) zone analysis system for regional evaluation of the cephalic fixator tip based on the ED of the cephalic fixator tip referenced to the radius of its own femoral head to predict cut-out in intertrochanteric fractures (ITF) with internal fixation.

Methods

First, we assumed all the femoral heads were regular spheres with the radius (R_FD) of “3” for a complete match of the Cleveland zone system and calculated the ED of the cephalic fixator tip by measuring the distances from the cephalic fixator tip to the geometric central axis in the femoral neck and head on both anteroposterior (AP) view and lateral view radiographs. Second, we defined the maximum transverse section of the femoral head into three zones named ED Zone A with ED less than “1,” Zone B with ED ranging in “1–2,” and Zone C with ED ranging in “2–3” in turns by concentric circles (circles A, B, and C) with the radius of 1/3, 2/3, and 3/3 times of R_FD, respectively. Third, we evaluated the ED zones according to the ED and location of the cephalic fixator tip in the eligible 123 ITF patients with single-screw cephalomedullary nail (SCMN) fixation and then analyzed the correlation between the cut-out rate and the ED zones.

Results

The cut-out rates in ED Zones A, B, and C were 4.17%, 38.46%, and 100%, respectively. Multivariate logistic regression indicated that ED Zone A had at least a 14 times lower rate of cut-out compared with ED Zone B. The cephalic fixator tip located in ED Zone A has a lower cut-out rate than that in Cleveland Zone 5. The cut-out rate in ED Zone A is significantly lower than that in the region inside Cleveland Zone 5 but outside ED Zone A.

Conclusion

ED zone analysis system is a reliable regional evaluation of the cephalic fixator tip position for predicting cut-out in geriatric ITF patients with SCMN fixations and potentially an artificial intelligence measurement during surgery. For decreasing the cut-out rate, the cephalic fixator tip should be located in ED Zone A.