THR: Acetabular Component Anteversion:


- Discussion:  
     - see native acetabular anteversion and femoral anteversion and acetabular component position
     - general considerations:
              - simple visualization of length of anterior/posterior walls gives an accurate measure of native anteversion;
              - references:
                      - Femoral anteversion in THA and its lack of correlation with native acetabular anteversion.
                      - The effect of the orientation of the acetabular and femoral components on the range of motion of the hip at different head-neck ratios.
                      - Does Acetabular Retroversion Affect Range of Motion after Total Hip Arthroplasty?
                     
- The 2014 Frank Stinchfield Award: The 'landing zone' for wear and stability in total hip arthroplasty is smaller than we thought: a computational analysis.

       - effect of decreased/insufficient anteversion:          
             
- psoas tendonititis:
              - references:
                  - Influence of component positions on dislocation: computed tomographic evaluations in a consecutive series of total hip arthroplasty.
                  - Dislocation After Total Hip Arthroplasty. Causes and Prevention.
                  - Factors predisposing to dislocation after primary total hip arthroplasty. A multivariate analysis.
                  - Acetabular revision for recurrent dislocations: results in 14 cases after 3 years of follow-up.
                  - Position, orientation and component interaction in dislocation of the total hip prosthesis
                  -
Iliopsoas Impingement After Primary Total Hip Arthroplasty: Operative and Nonoperative Treatment Outcomes.

      - effect of increased/excessive anteversion:
 (see painful hip replacement
              - impingement will occur in hip extension/ER during the toe off phase;
              - posterior impingement (due to increased anteversion) will be increased with addition of posterior positioning of the extended rim;  
              - references:
                      - Increased anteversion of press-fit femoral stems compared with anatomic femur. 
                      - Anterior dislocation of a total hip replacement. Radiographic and CT-scan assessment. Behavior following conservative management.
                      - Posterior femoral neck impingement secondary to excess acetabular anteversion in hip resurfacing arthroplasty.
                      - The spatial location of impingement in total hip arthroplasty
                      - Cup-neck impingement due to the malposition of the implant as a possible mechanism for metallosis in metal-on-metal total hip arthroplasty.
                      - Anterior Subluxation after Total Hip Replacement Confirmed by Radiographs: Report of Two Cases
                      - Anterior Dislocation Following Primary THR by the Posterior Approach — Aetiology and Treatment
                      -
Increased Anteversion of Press-fit Femoral Stems Compared With Anatomic Femur

     - Intraoperative Determination of Component Anteversion:
              - patient position:
                     - note that it can be difficult to judge component flexion on the OR table due to patient position; 
                     - if the patient is tilted posteriorly, there will be a tendency to ream the component in retroversion (and vice versa); 
                     - in the lateral position, if the patient's pelvis is flexed relative to the torso, the surgeon the ream the component in a
                               retroverted position (if degree of anteversion is calculated off of patient's torso); 
                     - references:
                               - Accuracy of intraoperative assessment of acetabular prosthesis placement
                               - Combined Anteversion Technique for Total Hip Arthroplasty
              - Native Anteversion:
                     - Does Native Hip Anatomy Fit Recommendations for Safe Component Orientation in THA?
                     - Femoral Anteversion in THA and its Lack of Correlation with Native Acetabular Anteversion.
                     - Comparison of native anatomy with recommended safe component orientation in total hip arthroplasty for primary osteoarthritis.

              - McCollum's line extends from anterosuperior iliac spine to the sciatic notch; 
                       - this gives a reproducible landmark to help the surgeon gage the proper angle of reaming; 
                       - generally the line of reaming and cup insertion is either perpendicular to McCollum's line or is slightly anterior to the line;
                        - safe rande for flexion was 20 degrees to 40 degrees; 
                        - when cup was positioned in 20 deg flexion impingement was occasionally noticed w/ hip flexed to 90 deg & IR to 90 deg;
                        - to eliminate impingement of prosthetic neck against the prosthetic cup, flexion was increased to 30 degrees; 
              - Transverse acetabular ligament as a refererence for anteversion:
                        - The Transverse Acetabular Ligament: Optimizing Version
                        - Anteversion of the acetabular component aligned with the transverse acetabular ligament in total hip arthroplasty.
                        - Is transverse acetabular ligament an anatomical landmark to reliably orient the cup in primary total hip arthroplasty
                        - The role of the transverse acetabular ligament for acetabular component orientation in total hip replacement: an analysis of acetabular component position and range of movement using navigation software.
                        - The transverse acetabular ligament may be used to align the acetabular cup in total hip arthroplasty
                        - Acetabular component positioning using the transverse acetabular ligament: can you find it and does it help?
                        - The relationship of the orientation of the transverse acetabular ligament and acetabular labrum to the suggested safe zones of cup positioning in total hip arthroplasty.                        - Reducing the rate of early primary hip dislocation by combining a change in surgical technique and an increase in femoral head diameter to 36 mm.
                        -
Total hip replacement through a posterior approach using a 22 mm diameter femoral head : the role of the transverse acetabular ligament and capsular repair in reducing the rate of dislocation.

Postoperative Radiographic Evaluation:
       - see postoperative radiographic evaluation of cup position
       - measurement of postoperative anteversion:
              - Anteversion of the acetabular cup. Measurement of angle after total hip replacement.
              - A simplified method to determine acetabular cup anteversion from plain radiographs.

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 Influence of the sagittal balance of the spine on the anterior pelvic plane and on the acetabular orientation.



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Tuesday, September 5, 2017 8:31 am