Block-step asymmetry 5 years after large-head metal-on-metal total hip arthroplasty is related to lower muscle mass and leg power on the implant side.

BACKGROUND Metal-on-metal articulations mimic the human hip anatomy, presumably lower dislocation rates and increase the range-of-motion. This study aims to measure the muscle mass and power of both legs in patients with unilateral metal-on-metal total hip arthroplasty, and to investigate their effect on block-step test, spatio-temporal gait parameters and self-reported function. METHODS Twenty-eight patients (7 women), mean age 50 (28-68) years, participated in a 5-7 year follow-up. Patients had received one type unilateral large-head metal-on-metal total hip articulation, all of which were well-functioning at follow-up. Mean muscle mass was measured by the total-body Dual energy X-ray Absorption scans, and muscle power was measured in a leg extensor power rig. Block-step test and spatio-temporal gait parameters were measured with an inertial measurement unit. Self-reported function was assessed by the Hip Disability and Osteoarthritis Outcome Score. FINDINGS We found a significant difference between the mean muscle mass of the implant-side leg and the non-implant-side leg in hip, thigh and calf areas (P<0.008) and in mean muscle power (P=0.025). Correlations between mean muscle mass and mean muscle power were significant for both the implant-side leg (r=0.45, P=0.018) and the non-implant-side leg (r=0.51, P=0.007). The difference in mean muscle power between legs correlated with block-step test asymmetry during ascending (r=0.40, P=0.047) and descending (r=0.53, P=0.006). Correlations between self-reported function and power of the implant-side leg were not significant. INTERPRETATIONS Young patients have not fully regained muscle mass, muscle power and function 5-7 years after metal-on-metal total hip arthroplasty.

[1]  P. Costigan,et al.  Hip moments during level walking, stair climbing, and exercise in individuals aged 55 years or older. , 1999, Physical therapy.

[2]  B J McFadyen,et al.  Three-dimensional gait analysis in women with a total hip arthroplasty. , 2000, Clinical biomechanics.

[3]  C. Jinks,et al.  Health status after hip or knee arthroplasty , 2003, Annals of the rheumatic diseases.

[4]  H. Berg,et al.  Reduced muscle radiological density, cross-sectional area, and strength of major hip and knee muscles in 22 patients with hip osteoarthritis , 2007, Acta orthopaedica.

[5]  E Byrne,et al.  Quadriceps muscle wasting persists 5 months after total hip arthroplasty for osteoarthritis of the hip: a pilot study , 2001, Internal medicine journal.

[6]  A. Hof,et al.  Assessment of spatio-temporal gait parameters from trunk accelerations during human walking. , 2003, Gait & posture.

[7]  Nico Verdonschot,et al.  Preoperative Ambulatory Measurement of Asymmetric Leg Loading During Sit-to-Stand in Hip Arthroplasty Patients , 2014, IEEE Transactions on Neural Systems and Rehabilitation Engineering.

[8]  Douglas G. Altman,et al.  Practical statistics for medical research , 1990 .

[9]  Dodd,et al.  Lateral pelvic displacement during walking: retest reliability of a new method of measurement. , 1998, Gait & posture.

[10]  M. Elia,et al.  Modeling Leg Sections by Bioelectrical Impedance Analysis, Dual‐Energy X‐ray Absorptiometry, and Anthropometry: Assessing Segmental Muscle Volume Using Magnetic Resonance Imaging as a Reference , 2000, Annals of the New York Academy of Sciences.

[11]  B. Stulberg,et al.  Early return to function after hip resurfacing: is it better than contemporary total hip arthroplasty? , 2010, The Journal of arthroplasty.

[12]  V. Licari,et al.  No Difference in Gait Recovery After THA With Different Head Diameters: A Prospective Randomized Study , 2013, Clinical orthopaedics and related research.

[13]  Julie Nantel,et al.  Center of Mass Compensation during Gait in Hip Arthroplasty Patients: Comparison between Large Diameter Head Total Hip Arthroplasty and Hip Resurfacing , 2011, Rehabilitation research and practice.

[14]  D. Hurwitz,et al.  Do gait adaptations during stair climbing result in changes in implant forces in subjects with total hip replacements compared to normal subjects? , 2008, Clinical biomechanics.

[15]  M. Kennedy,et al.  Introduction of a new critical p value correction method for statistical significance analysis of metabonomics data , 2013, Analytical and Bioanalytical Chemistry.

[16]  G. Bannister,et al.  Patient-reported outcomes after total hip and knee arthroplasty: comparison of midterm results. , 2009, The Journal of arthroplasty.

[17]  Rafael C González,et al.  Real-time gait event detection for normal subjects from lower trunk accelerations. , 2010, Gait & posture.

[18]  K. Pfeifer,et al.  Walking patterns of hip arthroplasty patients: some observations on the medio-lateral excursions of the trunk , 2003, Disability and rehabilitation.

[19]  Mario Lamontagne,et al.  Comparison of joint mechanics of both lower limbs of tha patients with healthy participants during stair ascent and descent , 2011, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[20]  D. Murray,et al.  Outcomes after metal-on-metal hip resurfacing: could we achieve better function? , 2008, Archives of physical medicine and rehabilitation.

[21]  J. Allum,et al.  Improvements in balance after total hip replacement. , 2005, The Journal of bone and joint surgery. British volume.

[22]  Rachel Senden,et al.  Acceleration-Based Motion Analysis as a Tool for Rehabilitation: Exploration in Simulated Functional Knee Limited Walking Conditions , 2011, American journal of physical medicine & rehabilitation.

[23]  S A A N Bolink,et al.  Inertial sensor motion analysis of gait, sit–stand transfers and step-up transfers: differentiating knee patients from healthy controls , 2012, Physiological measurement.

[24]  K. Meijer,et al.  Acceleration-based gait test for healthy subjects: reliability and reference data. , 2009, Gait & posture.

[25]  Andrew Gelman,et al.  Why We (Usually) Don't Have to Worry About Multiple Comparisons , 2009, 0907.2478.

[26]  J. M. Davies,et al.  Strength, power and related functional ability of healthy people aged 65-89 years. , 1994, Age and ageing.

[27]  A. Hof Scaling gait data to body size , 1996 .

[28]  W. Zijlstra,et al.  Recovery of gait after short-stay total hip arthroplasty. , 2007, Archives of physical medicine and rehabilitation.

[29]  R. Pietrobon,et al.  Metal-on-Metal Hip Resurfacing Compares Favorably with THA at 2 Years Followup , 2006, Clinical orthopaedics and related research.

[30]  T. Vail,et al.  Stair ascending and descending in hip resurfacing and large head total hip arthroplasty patients. , 2013, The Journal of arthroplasty.

[31]  D C Voaklander,et al.  Health related quality of life outcomes after total hip and knee arthroplasties in a community based population. , 2000, The Journal of rheumatology.

[32]  Chris Kirtley,et al.  Chapter 3 – Three-dimensional gait analysis , 2006 .

[33]  M. Klässbo,et al.  Hip disability and osteoarthritis outcome scoreAn extension of the Western Ontario and McMaster Universities Osteoarthritis Index , 2003, Scandinavian journal of rheumatology.

[34]  E. Roos,et al.  Agreement and Reliability of Functional Performance and Muscle Power in Patients with Advanced Osteoarthritis of the Hip or Knee , 2012, American journal of physical medicine & rehabilitation.

[35]  M. Elia,et al.  Assessment of limb muscle and adipose tissue by dual-energy X-ray absorptiometry using magnetic resonance imaging for comparison , 1999, International Journal of Obesity.

[36]  Meg E Morris,et al.  Lateral pelvic displacement during gait: abnormalities after stroke and changes during the first month of rehabilitation. , 2003, Archives of physical medicine and rehabilitation.

[37]  E. Bassey,et al.  A new method for measuring power output in a single leg extension: feasibility, reliability and validity , 2004, European Journal of Applied Physiology and Occupational Physiology.

[38]  H. Berg,et al.  Muscle strength, gait, and balance in 20 patients with hip osteoarthritis followed for 2 years after THA , 2010, Acta orthopaedica.

[39]  R. Emerson,et al.  Outcomes of total hip arthroplasty: a study of patients one year postsurgery. , 2002, The Journal of orthopaedic and sports physical therapy.

[40]  R. Christensen,et al.  Postoperative effects of neuromuscular exercise prior to hip or knee arthroplasty: a randomised controlled trial , 2013, Annals of the rheumatic diseases.

[41]  H. Berg,et al.  Persisting muscle atrophy two years after replacement of the hip. , 2009, The Journal of bone and joint surgery. British volume.

[42]  Roland Starr,et al.  Gait analysis of patients with resurfacing hip arthroplasty compared with hip osteoarthritis and standard total hip arthroplasty. , 2007, The Journal of arthroplasty.

[43]  E. Roos,et al.  Hip disability and osteoarthritis outcome score (HOOS) – validity and responsiveness in total hip replacement , 2003, BMC musculoskeletal disorders.

[44]  Wiebren Zijlstra,et al.  Accelerometry based assessment of gait parameters in children. , 2006, Gait & posture.

[45]  J. Varmarken,et al.  Similar range of motion and function after resurfacing large–head or standard total hip arthroplasty , 2013, Acta orthopaedica.

[46]  T. Rantanen,et al.  Muscle strength before and mortality after a bone fracture in older people , 2002, Scandinavian journal of medicine & science in sports.

[47]  M. Lavigne,et al.  Biomechanical reconstruction of the hip: a randomised study comparing total hip resurfacing and total hip arthroplasty. , 2006, The Journal of bone and joint surgery. British volume.

[48]  Aaron G Rosenberg,et al.  Changing Demographics of Patients with Total Joint Replacement , 2006, Clinical orthopaedics and related research.