Cement distribution and initial fixability of trochanteric fixation nail advanced (TFNA) helical blades

Design innovation and rationale of the intramedullary implants for treating Intertrochanteric fractures: A review

Intertrochanteric fracture management require effective management strategies for early return to function and minimise complications. Intramedullary devices like proximal femoral nail have an biomechanical advantage, particularly in unstable intertrochanteric fractures. Such unstable injury patterns not only require precise reduction technique, but also right implant design to minimise the complications. Novel concepts of reduction like medial cortical support classification and antero-posterior reduction (Subtype classification system) refine the reduction strategies. Despite reporting of the reduction analysis, there has been continuing number of implant failures following proximal femoral nail implantation. Complications like 'Z' effect and reverse 'Z' effect are very well reported with the 2 screw Recon - Proximal femur nails. Analysis of failure and complications have constantly upgraded the designs of proximal femur nails. Design of the new generation intramedullary implants for treatment of intertrochanteric fractures like Gamma nail, PFNA-II (Proximal Femoral Nail Anterotation), Zimmer Natural Nail, Trigen Intertan nail and TFN - Advanced (Trochanteric Femoral Nail Advanced) are described in this review. While the new implant designs offer advancements, fundamental principles of reduction remains crucial for successful outcomes. Design rationale and instrumentation of each implant must be known at the time of application along with techniques of maintaining the reduction for a successful outcome.

Augmented versus non-augmented Trochanteric Fixation Nail-Advanced (TFNA) nails for treating trochanteric fractures in patients over sixty-five years of age

PURPOSE

Intramedullary nailing is a common treatment for pertrochanteric fractures. However, implant-related mechanical failures, such as cut-out and cut-through, lead to higher rates of revision surgery, loss of autonomy, and mortality. Cemented augmentation enhances the bone-implant interface. This study compared the frequency of mechanical failures between augmented and non-augmented Trochanteric Fixation Nail-Advanced (TFNA) nails.

METHODS

This descriptive, retrospective study at a level 1 trauma centre included patients aged > 65 years with pertrochanteric fractures treated by a short augmented or non-augmented TFNA nail. The primary outcome was the comparison of cut-out or cut-through rates between groups at three and six months postoperatively.

RESULTS

Of the 181 patients analysed, 103 had augmented TFNA nails and 78 had non-augmented TFNA nails. There were no statistically significant differences between groups in terms of demographic characteristics, AO/OTA classification, or quality of reduction. The failure rate was significantly lower in the augmented group than in the non-augmented group: 1 (0.97%) versus 9 (11.54%) (p = 0.005). At six months postoperatively, there was no significant difference between the two groups concerning functional recovery, as measured by the Parker and EuroQoL 5-Dimensions scores.

CONCLUSIONS

For patients aged over 65 years, the use of the augmented TFNA nail may reduce the risk of fixation failures such as cut-out.

Which head element is more effective for cement augmentation of TFNA? Helical blade versus lag screw

BACKGROUND

Early fixation and rehabilitation is the gold standard treatment for intertrochanteric femur fractures. Cement augmentation through perforated head elements has been developed to avoid postoperative complications such as cut-out or cut-through. The purpose of this study was to compare two head elements in terms of cement distribution using computed tomography (CT) and to examine their initial fixation and clinical outcomes.

METHODS

Elderly patients who had intertrochanteric fractures were treated with a trochanteric fixation nail advanced (TFNA) helical blade (Blade group) or a TFNA lag screw (Screw group). In both groups, 4.2 mL of cement was injected under an image intensifier (1.8 mL of cement was directed cranially and 0.8 mL each caudally, anteriorly, and posteriorly). Patient demographics and clinical outcome were investigated post-operatively. Cement distribution from the center of the head element was evaluated with CT. Maximum penetration depth (MPD) were measured in the coronal and sagittal planes. On each axial plane, the cross-sectional areas in the cranial, caudal, anterior and posterior directions were calculated. The sum of cross-sectional areas (successive 36 slices) was defined as the volume of the head element.

RESULTS

The Blade group included 14 patients, and the Screw group included 15 patients. In the Blade group, MPD in the anterior and caudal direction was significantly greater than that in the posterior direction (p < 0.01). In the Screw group, volume in the cranial and posterior direction was significantly greater than that in the Blade group (p = 0.03). Subsequently, the total volume in the Screw group was significantly larger than that in the Blade group (p < 0.01). No significant correlation was detected between bone mineral density, T score, young adult mean, and total cement volume. Change in radiographic parameters and clinical outcome such as Parker score and visual analog scale were similar in both groups. No patients suffered from cut-out / cut through or non-union.

CONCLUSIONS

The position of cement distribution through the lag screw is different from that through the helical blade, and the total volume of the head element is significantly larger in the lag screw. Both groups had similarly effective results in terms of mechanical stability after surgery, postoperative pain and early phase of rehabilitation.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN45341843, 24/12/2022, Retrospectively registered.

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.

Effectiveness of Cement Augmentation on Early Postoperative Mobility in Patients Treated for Trochanteric Fractures with Cephalomedullary Nailing: A Prospective Cohort Study

Fixation using cephalomedullary nails (CMNs) with additional cement augmentation (CA) was developed as a novel treatment option for the osteosynthesis of osteoporotic trochanteric fractures, though the effectiveness of CA on early postoperative mobility remains uncertain. This multicenter prospective cohort study aimed to estimate the effectiveness of CA on early postoperative mobility in patients with trochanteric fractures. We enrolled patients with femoral trochanteric fractures aged >60 years who were able to walk independently before the injury. The primary outcome was the postoperative 3-day cumulated ambulation score (CAS); the secondary outcome was the visual analog scale (VAS) pain score at rest and during movement on postoperative days 1−3. The outcomes of the patients treated using CMNs with or without CA were compared. Sixty-three eligible patients were categorized into CA (n = 32) and control (n = 31) groups. In univariate analysis, the CA group had significantly higher CAS values, lower VAS scores at rest on day 1 postoperatively, and lower VAS scores during movement on day 3. In multivariable linear regression analyses, the CA group had significantly higher CAS values (beta, 2.1; 95% confidence interval, 0.5 to 3.6; p = 0.01). The CA group had a negative adjusted beta value in their VAS scores during movement. This study indicated that CA was associated with a high CAS value in patients with geriatric trochanteric fractures. However, CA was not associated with pain reduction at rest and during movement during the initial postoperative days.