How Superior Placement of the Joint Center in Hip Arthroplasty Affects the Abductor Muscles

This study examines the effects of a superiorly placed hip center on the strength of the abductor muscles. A 3-dimensional computer model of the hip and the surrounding musculature was used to calculate the moment arms, forces, and moments generated when the hip abductor muscles are maximally activated. A representation of a hip prosthesis was implanted into the computer model with altered hip center positions and a range of prosthetic neck lengths. Analysis of these simulated hip replacements demonstrated that superolateral placement of the hip center (2 cm superior and 2 cm lateral) decreases the moment arms of the hip abductor muscles by an average of 28%. This decrease in moment arm cannot be restored by increasing prosthetic neck length, resulting in an unrecoverable loss of abduction strength with superolateral displacement. By contrast, a 2-cm superior displacement of the hip center changes the moment arms and force generating capacities of the abductors by less than 10% if prosthetic neck length is increased to compensate for decreased muscle length. The results of this study suggest that superior positioning of the hip center, without lateral placement, does not have major, adverse effects on abduction moment arms or force generating capacities when the neck length is appropriately increased.

[1]  V. T. Inman.  Functional aspects of the abductor muscles of the hip. , 1947, The Journal of bone and joint surgery. American volume.

[2]  R C Johnston,et al.  Mechanical analysis and optimization of a cup arthroplasty. , 1969, Journal of biomechanics.

[3]  Biomechanics of cup arthroplasty. , 1969, Clinical orthopaedics and related research.

[4]  Biomechanics of cup arthroplasty. , 1969 .

[5]  J. Charnley,et al.  Total hip replacement by low-friction arthroplasty. , 1970, Clinical orthopaedics and related research.

[6]  M. Müller.  Total hip prostheses. , 1970, Clinical orthopaedics and related research.

[7]  Müller Me.  Total hip prostheses. , 1970 .

[8]  G. Smidt,et al.  The maximum torque generated by the eccentric, isometric, and concentric contractions of the hip abductor muscles. , 1972, Physical therapy.

[9]  S B Sepic,et al.  Roentgenographic measurements after Müller total hip replacement. Correlations among roentgenographic measurements and hip strength and mobility. , 1977, The Journal of bone and joint surgery. American volume.

[10]  S. Simon,et al.  Total hip replacement with and without osteotomy of the greater trochanter. Clinical and biomechanical comparisons in the same patients. , 1978, The Journal of bone and joint surgery. American volume.

[11]  G. Goldspink,et al.  Changes in sarcomere length and physiological properties in immobilized muscle. , 1978, Journal of anatomy.

[12]  R. Crowninshield,et al.  Reconstruction of the hip. A mathematical approach to determine optimum geometric relationships. , 1979, The Journal of bone and joint surgery. American volume.

[13]  Murray Mp,et al.  Anterolateral compared to posterior approach in total hip arthroplasty: differences in component positioning, hip strength, and hip motion. , 1982, Clinical orthopaedics and related research.

[14]  V. Edgerton,et al.  Muscle architecture of the human lower limb. , 1983, Clinical orthopaedics and related research.

[15]  P. D. Wilson,et al.  Results of revision for mechanical failure after cemented total hip replacement, 1979 to 1982. A two to five-year follow-up. , 1985, The Journal of bone and joint surgery. American volume.

[16]  L. Latta,et al.  Abductor muscle performance in total hip arthroplasty with and without trochanteric osteotomy. Radiographic and mechanical analyses. , 1985, Clinical orthopaedics and related research.

[17]  C. Ranawat,et al.  Total hip arthroplasty in juvenile rheumatoid arthritis. Two to eleven-year results. , 1986, The Journal of bone and joint surgery. American volume.

[18]  American Academy of Orthopaedic Surgeonsʼ Atlas of Orthotics—Biomechanical Principles and Application , 1987 .

[19]  R. Brand,et al.  Total hip acetabular component position affects component loosening rates. , 1988, Clinical orthopaedics and related research.

[20]  F. Zajac.  Muscle and tendon: properties, models, scaling, and application to biomechanics and motor control. , 1989, Critical reviews in biomedical engineering.

[21]  C. Arnoldi,et al.  Arthroplasty for congenital hip dislocation. Techniques for acetabular reconstruction. , 1989, Acta orthopaedica Scandinavica.

[22]  F. Convery,et al.  Acetabular augmentation in primary and revision total hip arthroplasty with cementless prostheses. , 1990, Clinical orthopaedics and related research.

[23]  R. N. Stauffer.  Bone Stock Deficiency in Total Hip Replacement: Classification and Management , 1990 .

[24]  R. Brand,et al.  Muscle fiber architecture in the human lower limb. , 1990, Journal of biomechanics.

[25]  F.E. Zajac,et al.  An interactive graphics-based model of the lower extremity to study orthopaedic surgical procedures , 1990, IEEE Transactions on Biomedical Engineering.

[26]  G. Wolfgang,et al.  Femoral head autografting with total hip arthroplasty for lateral acetabular dysplasia. A 12-year experience. , 1990, Clinical orthopaedics and related research.

[27]  C. Engh,et al.  Cementless total hip arthroplasty with femoral head bone grafting for hip dysplasia. , 1990, The Journal of arthroplasty.

[28]  R. Barrack,et al.  Uncemented total hip arthroplasty with superior acetabular deficiency. Femoral head autograft technique and early clinical results. , 1990, The Journal of arthroplasty.

[29]  D. Winter,et al.  Control of Balance of Upper Body During Gait , 1990 .

[30]  W. Harris,et al.  Salvage total hip reconstruction in patients with major acetabular bone deficiency using structural femoral head allografts. , 1990, The Journal of bone and joint surgery. British volume.

[31]  W. Harris,et al.  Proximal placement of the acetabular component in total hip arthroplasty. A long-term follow-up study. , 1991, The Journal of bone and joint surgery. American volume.

[32]  J. D’Antonio.  Periprosthetic bone loss of the acetabulum. Classification and management. , 1992, The Orthopedic clinics of North America.

[33]  E. Salvati,et al.  Bone graft and total hip arthroplasty. A review. , 1992, The Journal of arthroplasty.

[34]  D'Antonio Ja.  Periprosthetic bone loss of the acetabulum. Classification and management. , 1992 .

[35]  S. Delp,et al.  Effects of hip center location on the moment-generating capacity of the muscles. , 1993, Journal of biomechanics.

[36]  S. Delp,et al.  Superior displacement of the hip in total joint replacement: Effects of prosthetic neck length, neck‐stem angle, and anteversion angle on the moment‐generating capacity of the muscles , 1994, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[37]  W H Harris,et al.  High placement of porous-coated acetabular components in complex total hip arthroplasty. , 1994, The Journal of arthroplasty.

[38]  S. Kelley.  High hip center in revision arthroplasty. , 1994, The Journal of arthroplasty.