Clinical Scorecard: Assessing the Anatomical Diversity of the Proximal Femur

At a Glance

Key Highlights

• Native femoral version (NFV) does not reliably predict prosthetic femoral version (PFV) due to anatomical variability.
• A sex-specific statistical shape model (SSM) was developed to quantify 3D morphological variability of the proximal femur pre- and post-operatively.
• Patient-specific femoral neck osteotomy guides enable accurate simulation and execution of planned osteotomy cuts.

Guideline-Based Recommendations

Diagnosis

• Use preoperative CT imaging to assess proximal femoral anatomy and plan osteotomy.
• Segment native proximal femur, post-osteotomy femur, and intramedullary canal for detailed morphological analysis.

Management

• Consider variability in femoral canal shape when selecting cementless femoral stem design.
• Use patient-specific osteotomy guides to improve accuracy of femoral neck cuts.
• Aim for prosthetic femoral version (PFV) target of 20° ± 5°, recognizing intraoperative adjustment limitations.

Monitoring & Follow-up

• Perform post-operative CT scans to evaluate reconstructed femur and stem positioning.
• Use statistical shape models to correlate anatomical variations with surgical outcomes.

Risks

• Inaccurate prediction of PFV may lead to suboptimal biomechanics and fixation.
• Limited intraoperative ability to adjust stem rotation may affect final implant orientation.

Patient & Prescribing Data

62 patients (31 male, 31 female) undergoing cementless THA with Quadra®–H stem for osteoarthritis

Despite targeting a PFV of 20° ± 5°, achieved PFV varies widely due to anatomical differences and limited rotational control during surgery.

Clinical Best Practices

• Utilize patient-specific femoral neck osteotomy guides to replicate preoperative plans accurately.
• Incorporate 3D imaging and segmentation to understand individual femoral morphology before stem selection.
• Recognize the limitations of current cementless stem designs in restoring optimal biomechanics due to anatomical variability.

References

• Medacta International Quadra®–H stem
• Simpleware ScanIP Medical software
• Patient-specific femoral neck osteotomy guide (MyHip)