The greater trochanter-head contact method: a cadaveric study with a new technique for the intraoperative control of rotation of femoral fractures

Acute Correction of Femoral Malrotation After Intramedullary Nailing Using an Intraoperative Digital Protractor

OBJECTIVE

 The goal of the study is to diagnose and accurately correct malrotation of femur fractures after intramedullary (IM) nailing.

MATERIALS AND METHODS

An institutional review board (IRB) approved prospective study that was performed at a U.S. level 1 trauma center. After IM nailing of comminuted femur fractures, a computed tomography (CT) scanogram was routinely performed to detect the difference in the postoperative femoral version. Patients with malalignment greater than 15 degrees compared to the contralateral side were informed about the discrepancy and offered to have it acutely corrected. A four-pin technique was used: two Schanz pins were used for measuring angles and two different pins were used to turn and correct the malalignment. The pin in the distal fragment is placed directly under the nail to prevent shortening in comminuted fractures. The nail was unlocked either proximally for retrograde nails or distally for antegrade nails. The Bonesetter Angle application was used as a digital protractor to intraoperatively measure the two reference pins and correct the malrotation. Alternate holes were used for relocking the nail. All patients received a CT scanogram after correction.

RESULTS

 19/128 patients with comminuted femoral fractures over five years with malrotations between 18 and 47 degrees were included in the study with an average malrotation of 24.7 + 8 degrees. All patients were corrected to an average of 4.0 +/- 2.1 degrees difference, as compared to the contralateral side (range 0-8). No patients required further surgeries to correct malrotation.

CONCLUSION

 Comminuted fractures with malrotation >15 degrees after femoral nailing have an incidence of 15% at our institution. This technique provides an efficient and accurate correction method with the use of an intraoperative digital protractor, avoiding the need for revision IM nailing or osteotomies.

Custom 3D-Printed Cutting Guides for Femoral Osteotomy in Rotational Malalignment Due to Diaphyseal Fractures: Surgical Technique and Case Series

Femoral shaft fractures are one of the most common injuries in trauma patients. The gold standard treatment consists of closed reduction and intramedullary nailing, providing a high fracture healing rate and allowing early mobilization. However, rotational malalignment is a well-known complication following this procedure, and excessive femoral anteversion or femoral retroversion can trigger functional complaints. In order to achieve the ideal degree of femoral rotation, a 3D planning and printing cutting guides procedure was developed to correct femoral malrotation. A patient series with malalignment after a femoral diaphyseal fracture was operated on with the customized guides and evaluated in this study. Computed tomography scans were performed to accurately determine the number of degrees of malrotation, allowing the design of specific and personalized surgical guides to correct these accurately. Once designed, they were produced by 3D printing. After surgery with the customized guides to correct femoral malrotation, all patients presented a normalized anteversion angle of the femur (average −10.3°, range from −5° to −15°), according to their contralateral limb. These data suggest that the use of customized cutting guides for femoral osteotomy is a safe and reproducible surgical technique that offers precise results when correcting femoral malrotation.

Use of Inherent Anteversion of an Intramedullary Nail to Avoid Malrotation in Comminuted Femur Fractures: A Prospective Case- Control Study

OBJECTIVES

To (1) evaluate using the inherent anteversion of a second or third generation femoral nail to set the version of the femur during locked intramedullary nailing of comminuted femoral shaft fractures (Espinosa Technique [ET]) and compare it with our traditional method (traditional group [TG]) and (2) assess the variation of anteversion because of the inherent play in the nail itself.

DESIGN

A prospective IRB-approved study.

SETTING

Academic US Level 1 Trauma Center.

PATIENTS

Fifty-two consecutive patients with comminuted femur fractures all completed the study.

INTERVENTION

The first 27 patients had the anteversion determined using the patellar shadow and lesser trochanter (TG), and the next 25 patients were treated by ET.

MAIN OUTCOME MEASURE

Computed tomography scanogram for femoral anteversion and length in the normal versus operated femur.

RESULTS

A >15 degree difference from native to operated legs was found in 8/27 TG (29%, 95% CI 15.3%-54.2%), with a mean difference of 11.6 ± 10.2 degrees (95% CI 8.8-16.17) verses 1/25 in the ET group (2.5%, 95% CI 0%-15.3%), with a mean difference of 4.8 ± 6.2 degrees (95% CI 1.38-8.9) (P = 0.0068). There was a 5 degree variability in our ability to center the proximal locking screw in the femoral head and 5 degrees variation in distal locking.

CONCLUSIONS

The inherent anteversion of a second generation nail can be used to minimize malrotation of the femur after comminuted fractures during locked intramedullary nailing in patients with normal anteversion and is superior to our present fluoroscopic technique.

LEVEL OF EVIDENCE

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

Reliable Method for Avoiding Malrotation Deformity After Intramedullary Nailing of Comminuted Femur Fractures: Clinical Validation of a Previously Described Technique

OBJECTIVES

To evaluate a previously described technique using the inherent anteversion of intramedullary nail (IMN) to avoid malrotation in comminuted femur fractures and describe the use of magnetic resonance imaging (MRI) as an alternative method for assessing postoperative femoral version.

DESIGN

Prospective consecutive cohort study.

SETTING

Level I trauma center.

PATIENT/PARTICIPANTS

Twenty-five consecutive patients with comminuted femur fractures (Winquist III/IV, OTA/AO 32-B/32-C) treated by a single surgeon with IMN between September 1, 2011, and February 28, 2015.

INTERVENTION

IMN on a fracture table with intraoperative femoral version set by the inherent version of the implant. All patients received a postoperative computed tomography (CT) or MRI to assess femoral version.

MAIN OUTCOME MEASUREMENTS

Mean difference in postoperative femoral anteversion (DFA) between injured limb and uninjured limb as measured by CT or MRI. Mean difference in postoperative femoral version of the injured femur from the inherent version of the implant (12 degrees) was measured with CT or MRI.

RESULTS

The mean postoperative DFA was 9.1 ± 5.6 degrees. Postoperative DFA greater than 15 degrees was found in 2 (8.0%) patients. Mean difference in postoperative version of the injured femur from the inherent 12 degrees of the implant was 7.1 ± 5.4 degrees. Patients tolerated MRI studies well.

CONCLUSIONS

Our previously described technique using the inherent anteversion of an IMN is effective and leads to a very low rate of malrotation, even in highly comminuted fractures. The technique is particularly useful in treating bilateral femur fractures. MRI can be used safely and effectively to assess anteversion after fixation of femur fractures.

LEVEL OF EVIDENCE

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

A Simple Method for Measurement of Femoral Anteversion-Validation and Assessment of Reproducibility

OBJECTIVES

To propose a simple method for measurement of femoral anteversion (AV) with a conventional fluoroscope, to evaluate the interobserver and intraobserver reliability of this method on the basis of human cadaver femurs, and to validate such method on the basis of computed tomography (CT).

METHODS

Fourteen human cadavers with 28 intact femurs were included in the study. Three blinded observers measured femoral AV of the specimen with a fluoroscope. The session was repeated 8 weeks later and CT of the femurs were performed. Mean AV values and the difference between single and mean AV values were calculated. Interobserver/intraobserver reliability of the proposed method was assessed. Correlation between AV values measured with fluoroscope and CT was calculated.

RESULTS

Mean AV was 18.1° when measured with fluoroscope and 19.2° when measured with CT. Mean differences between single AV values were 2.2° with fluoroscope and 2.5° with CT. The mean maximum observer variation per specimen was 8.8°. Interobserver reliability was excellent (intraclass correlation coefficient: 0.853) and intraobserver reliability was good (intraclass correlation coefficient: 0.682). A high correlation was found between AV values measured with fluoroscope and CT (rho = 0.739, P < 0.01).

CONCLUSION

The presented technique allows reliable and simple measurement of femoral AV with a conventional fluoroscope. The mean interobserver variation is comparable to what has been reported for CT. Maximum interobserver variation was <15° in all specimens. A clinical study will be necessary to prove the value of this technique for intraoperative adjustment of femoral AV according to the intact contralateral side.

Torsional malalignment, how much significant in the trochanteric fractures?

OBJECTIVES

The rotational alignment is definitely important in the long bones such as tibias and femurs. We also predict the importance of rotational alignment in the trochanteric fractures. So we measured torsional malalignment in trochanteric fracture and anlaysed their risk factors and their clinical significance.

METHODS

A total of 109 inpatients who had undergone internal fixation following trochanteric fracture and a postoperative pelvic CT scan between 2008 and 2013, with at least one year follow-up, were selected. Factors that affect torsional malalignment, such as age, gender, fracture stability, injured area, operative time, time of surgery after admission, and ASA status, were investigated. Factors that affect the patients' clinical results in malrotation, including ambulation time after surgery, postoperative complication rates, pain assessment of VAS one year postoperatively and Koval score, were also investigated.

RESULTS

Of the 109 subjects, torsional malalignment was observed in 28 (25.7%) subjects with a mean torsional malalignment angle of 20.7° (range: -31.2° to 27.1°). Torsional malalignment risk factors were fracture stability (p=0.021) and operative time (p=0.043). In terms of the time to ambulation after surgery, the postoperative complication rates, and the VAS and Koval scores at one year postoperatively, no statistically significant difference was observed between the torsional malalignment patients and the non-deformity patients.

CONCLUSIONS

In this study, 25.7% of the patients who had undergone internal fixation following trochanteric fracture experienced torsional malalignment. Major factors of the torsional malalignment were an unstable fracture and the consequent delay in the operative time. But the torsional malalignment was deemed to have no effect on clinical results.

Important tips and numbers on using the cortical step and diameter difference sign in assessing femoral rotation--should we abandon the technique?

Rotational malalignment during femoral nailing is common despite having various intraoperative assessment methods. The cortical step sign and diameter difference sign (CSSDDS) is commonly used because of convenience, yet it lack proper scientific scrutiny and is thought to be error prone. Using a software algorithm, cross-sectional dimensions were obtained from CT scans of 22 intact adult femurs at the proximal, mid and distal diaphysis. With multiple simulated scenarios the sensitivity of CSSDDS was comprehensively determined at all possible C-arm positions. At rotation, cortical width changed most significantly around the thick linea aspera and femoral diameter changed most significantly at the sagittal plane. At 15 degrees of rotation and with the linea aspera in view, CSSDDS thresholds of 0.3mm, 0.6mm and 1mm had sensitivities of 98.8%, 93.1% and 73.8%. With the linea aspera masked behind the femur and out of view, the sensitivities significantly deteriorated to 96.4%, 77.1% and 44.1% respectively. CSSDDS is sufficiently sensitive only when strict rules are followed. It is imperative that the operator position the image intensifier in lateral view under proper magnification so that steps of less than 0.6mm around the linea aspera may be appreciated.

Management of distal femur fractures with modern plates and nails: state of the art

Fractures of the distal femur, even those with articular extension, are well suited to surgical fixation with modern precontoured anatomic plates and nails. Numerous adjuvant techniques are available to the treating surgeon to obtain and maintain reduction while preserving fracture biology. Yet despite their proven track record and benefits over older implants, technical errors are common and must be overcome with proper preoperative planning and intraoperative attention to detail. This review summarizes the current state of the art regarding distal femur fractures, with an emphasis on relevant modern plate and nail surgical techniques, tempered by our current understanding of implant biomechanics, fracture healing, and long-term outcomes.

Use of inherent anteversion of an intramedullary nail to avoid malrotation in femur fractures

Rotational malalignment after intramedullary (IM) nailing of femoral fractures remains a significant problem. A technique using intraoperative fluoroscopy and the anteversion inherent to the IM nail for obtaining appropriate femoral rotational alignment is presented. The technique is advocated as a simple alternative to more complex methods for estimation of femoral anteversion during placement of femoral IM nails. This method is simple and requires intraoperative fluoroscopy on the injured extremity alone. It reliably sets the femoral anteversion within a normal physiologic range with minimal additional intraoperative steps and without preoperative measurements.