Loss of Reduction after Cephalomedullary Nail Fixation of Intertrochanteric Femoral Fracture: A Brief Report

Increased 1-Year Revision Rates Among Left-Sided Intertrochanteric Femur Fractures

OBJECTIVES

To compare 1-year revision rates among left-sided and right-sided intertrochanteric femur fractures.

METHODS

DESIGN

Retrospective.

SETTING

120+ contributing centers to multicentered database.

PATIENT SELECTION CRITERIA

Patients who sustained intertrochanteric femur fracture (ITFF) and had a cephalomedullary nail (CMN) from 2015 to 2022 were identified. Patients were then stratified based on left-sided or right-sided fracture. Patients were excluded if younger than 18 years with <1-year follow-up. The intervention investigated was CMN on left or right side.

OUTCOME MEASURES AND COMPARISONS

One-year revision surgery, comparing CMN performed on left or right side for ITFFs.

RESULTS

In total, 113,626 patients met inclusion criteria, with 55,295 in the right-sided cohort and 58,331 in the left-sided cohort. There was no difference between cohorts with respect to age, gender, diabetes, osteoporosis, chronic kidney disease, or congestive heart failure (P > 0.05 for all). Patients who sustained a left ITFF and treated with a CMN were more likely to have revision surgery at 1 year (Left: 1.24%, Right: 0.90%; OR: 1.24; 95% confidence interval [CI], 1.15-1.1.33) or develop a nonunion or malunion (Left: 1.30%, Right: 0.98%; OR: 1.31; 95% CI, 1.14-1.52). The most common revision surgery conducted for both cohorts was conversion total hip arthroplasty (Left: 70.4% and Right: 70.0%).

CONCLUSIONS

Patients who sustained a left intertrochanteric femur fracture and were treated with a CMN were more likely to undergo revision at 1 year due to nonunion. There were no differences in demographics and comorbidities between cohorts. Though left-sided versus right-sided confounding variables may exist, the difference in nonunion rate may be explained by clockwise torque of the lag screw used in most implants. Increased awareness, implant design, and improved technique during fracture reduction and fixation may help lower this disproportionate nonunion rate and its associated morbidity and financial impact.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

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.

Is Nail-Canal Diameter Discordance a Risk Factor for the Excessive Sliding of Cephalomedullary Nails in Geriatric Intertrochanteric Fracture Surgery?

Background and Objectives:: There were limited studies which investigated nail diameter as a predictor for cephalomedullary nail (CMN) failure in intertrochanteric fracture (ITF). We aimed to evaluate the surgical outcomes of CMN in fragility ITF following nail-canal (N-C) diameter discordance. Materials and Methods: From November 2010 to March 2022, we retrospectively reviewed 120 consecutive patients who underwent CMN surgeries due to fragility ITF. We included patients with acceptable reduction and a tip-apex distance ≤ 25 mm. The N-C diameter differences both in anterior-posterior (AP) and lateral-view X-rays were measured, and we compared the number of excessive sliding instances and the rate of implant failure between the N-C concordance (≤3 mm) and discordance (>3 mm) group. Simple linear regression was used to determine the strength of the relationship between the N-C difference and sliding distance. Results: The sliding distance showed no differences between the groups in the AP (3.6 vs. 3.3 mm, p = 0.75) and lateral view (3.5 vs. 3.4 mm, p = 0.91). For analyses in the AP view, the AP-concordance and AP-discordance groups had 14 (25%) and 14 patients (22%) with a sliding distance of >5 mm (p = 0.69), while treatment failure occurred in 3 (5%) and 3 (3%) patients, respectively (p = 0.66). For analyses in the lateral view, the lat-concordance and lat-discordance groups had 8 (27%) and 20 patients (22%) with a sliding distance of >5 mm (p = 0.62), while treatment failure occurred in 1 (3%) and 4 (4%) patients, respectively (p = 1.00). Linear regression analyses showed that the N-C difference in either views was not a significant predictor of sliding distance in both the AP (R² = 0.002, p = 0.60) and lateral views (R² = 0.007, p = 0.35). Conclusions: If appropriate fracture reduction and fixation are achieved, the N-C discordance of short CMN does not affect treatment outcomes in ITF.