Bony impingement affects range of motion after total hip arthroplasty: A subject-specific approach

Oliver Kessler, Shantanu Patil, Stephan Wirth, Wirth Stefan, Eckart Mayr, Clifford W Colwell, Darryl D D'Lima
Journal of Orthopaedic Research: Official Publication of the Orthopaedic Research Society 2008, 26 (4): 443-52
Hip range of motion after total hip arthroplasty has been shown to be dependent on prosthetic design and component placement. We hypothesized that bony anatomy would significantly affect range of motion. Computer models of a current generation hip arthroplasty design were virtually implanted in a model of pelvis and femur in various orientations ranging from 35 degrees to 55 degrees cup abduction, 0 degrees to 30 degrees cup anteversion, and 0 degrees to 30 degrees femoral anteversion. Four head sizes ranging from 22.2 to 32 mm and two neck sizes ranging from 10-mm and 12-mm diameter were tested. Range of motion was recorded as maximum flexion-extension, abduction-adduction, and axial rotation of the femur before any contact between prosthetic components or bone was detected. Bony impingement preceded component impingement in about 44% of all conditions tested, ranging from 66% in adduction to 22% in extension. Range of motion increased as head size increased. However, increasing head size also increased the propensity for bony impingement, which tended to reduce the beneficial effect of increased head size on range of motion. Reducing neck diameter had a greater effect on prosthetic impingement (mean, 3.5 degrees increase in range of motion) compared to bone impingement (mean, 1.9 degrees ). This model allowed for a clinically relevant assessment of range of motion after total hip arthroplasty and may also be used with patient-specific geometry [such as that obtained from preoperative computed tomography (CT) scans] for more accurate preoperative planning.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"