Is Hip Resurfacing a Viable Option for Patients with Hip OA?
Dr. George Grammatopoulos and Dr. Paul Beaulé answer questions from ICJR about their indications and experience with hip resurfacing as an alternative to total hip arthroplasty in patients with hip osteoarthritis.
ICJR: What are your indications for a hip resurfacing procedure?
Paul E. Beaulé, MD, FRCSC: Modern, third-generation metal-on-metal hip resurfacings (MoMHRAs) have now been available for 20 years. Over this period, results from designer series, [1-3] independent centers, [4,5] and registry data  have allowed us to confidently identify the optimal candidates for the procedure.
In our practice, the most common indication for a MoMHRA (more than 90% of patients) is a young (age 55 or younger), highly active male with end-stage hip osteoarthritis (OA). These patients tend to have cam-type of proximal femoral morphology with the associated early-development of OA (Figure 1).
Figure 1. Preoperative (left) and postoperative (right) AP radiographs of a 55-year-old male patient who was happy with his uncemented hip resurfacing arthroplasty on the left side (performed in 2012) and presented for the hip resurfacing on the contralateral side.
On the whole, a MoMHRA is offered to all male patients younger than age 65. The decision on whether to proceed with a MoMHRA rather than a total hip arthroplasty (THA) is always patient-oriented. Young men who have active lifestyles (sports as a hobby/favorite past-time) are more encouraged to consider a MoMHRA than those with sedentary lifestyles.
Uncommon indications for offering a MoMHRA include:
- Presence of metalwork in the hip that would require removal prior to proceeding with a THA
- Abnormal proximal femoral morphology that prevents accurate restoration of anatomy or the ability to implant a femoral component appropriately
Lastly, although a MoMHRA is not offered to any of our female patients, a very small number of MoMHRAs are performed each year in young (less than 50 years old), athletic females. These patients have either had a successful MoMHRA and have end-stage primary OA on the ipsilateral side or have reviewed the literature and are very keen to proceed with the MoMHRA despite the well-described risks.
Among the well-characterized factors influencing outcome is femoral head size.  All patients who are due for a MoMHRA are aware that if the femoral component size suitable for their anatomy is less than 48 mm, we will have to convert to a THA. This is not a common occurrence, however, especially with the use of templating software.
ICJR: What does the literature say about continuing to offer hip resurfacing?
George Grammatopoulos, MRCS: Independent centers and registry data continue to support the use of MoMHRA, although the indications have narrowed. Furthermore, as not all MoMHRAs are the same, only Food and Drug Administration-approved designs with good track record should be used.
There is general agreement in national guidelines and consensus statements  on whether hip resurfacings should be continued and what the indications should be. A MoMHRA is a suitable joint reconstruction option for young males (less than 55 years old) with primary OA and excellent long-term survival.
Hip resurfacing should be performed only by surgeons who have had the appropriate training in the procedure. There is little doubt that hip resurfacing is more technically challenging than THA, and particular attention must be given to:
- Preservation of vascularity [9,10]
- Improvement of the anterior head-neck offset 
- Appropriate component sizing [11,12]
- Appropriate component orientation 
ICJR: What outcomes have you observed with your hip resurfacing patients?
Dr. Grammatopoulos: Zylberberg et al  reported on Ottawa’s experience with hip resurfacing in 2015. The study included 548 consecutive hip resurfacings (458 patients) performed with the Conserve Plus design. The majority of patients were male (n=350, 76%).
At a mean follow-up of 6.6 years, 30 patients required conversion to THA. The 5-year implant survival was 94.5% (95% CI: 93.5 – 95.5%) and the 8-year survival was 93.5 (95% CI: 92.5 – 94.5%). Reasons for failure included:
- Acetabular component loosening (n=10)
- Femoral neck fracture (n=5)
- Femoral component loosening (n=5)
- Pseudotumor (n=5)
- Unexplained pain (n=4)
- Infection (n=1)
There was significant improvement in functional outcome following surgery, with the HHS improving from 53.6 (19) to 87 (15) (P<0.001). In addition, the HOOS scores improved from:
- 43 (17) to 86 (18) for pain
- 40 (18) to 81 (19) for symptoms
- 46 (20) to 86 (18) for function of daily living
- 24 (18) to 76 (23) for sporting ability
- 21 (17) to 70 (25) for quality of life
We have also published a randomized trial comparing cemented versus cementless femoral fixation. The study showed good functional outcome and favorable bone remodelling on the femoral side.  As a result, most of our femurs are implanted without cement.
ICJR: What percentage of hip resurfacings have you had to revise due to issues with the metal component?
Dr. Beaulé: At our center, all patients are followed up regularly after their MoMHRA. Any patient who complains of discomfort has additional soft-tissue imaging testing to determine if a soft-tissue reaction or pseudotumor has developed. An ultrasound scan is our investigation of choice for such patients. The prevalence of a revision due to a soft-tissue reaction among patients with MoMHRAs in our center is 1.5%.
The Ottawa experience of outcomes following revision of a failed MoMHRA has previously been reported.  Regular patient review and prompt revision on identification of a malfunctioning MoMHRA leads to good functional outcomes following revision.
This is in agreement with other reports in the literature,  indicating that there have been great advancements since the original description of the problems associated with such revisions. 
About the Experts
George Grammatopoulos, MRCS, and Paul E. Beaulé, MD, FRCSC, are from Division of Orthopaedic Surgery at The Ottawa Hospital, Ottawa, Ontario, Canada.
Dr. Grammatopoulos has no disclosures relevant to this article. Dr. Beaulé has disclosed that he is a consultant for MatORTHO, MicroPort, CORIN, Medacta, and Zimmer Biomet and that he receives royalties from CORIN, Medacta, and MicroPort.
- Amstutz, H. C.; Le Duff, M. J.; Campbell, P. A.; Gruen, T. A.; and Wisk, L. E.: Clinical and radiographic results of metal-on-metal hip resurfacing with a minimum ten-year follow-up. J Bone Joint Surg Am, 92(16): 2663-2671, 2010.
- McBryde, C. W.; Theivendran, K.; Thomas, A. M.; Treacy, R. B.; and Pynsent, P. B.: The influence of head size and sex on the outcome of Birmingham hip resurfacing. J Bone Joint Surg, 92A(1): 105-112, 2010.
- McMinn, D. J.; Daniel, J.; Ziaee, H.; and Pradhan, C.: Indications and results of hip resurfacing. Int Orthop, 35(2): 231-237, 2011.
- Murray, D. W.; Grammatopoulos, G.; Pandit, H.; Gundle, R.; Gill, H. S.; and McLardy-Smith, P.: The ten-year survival of the Birmingham hip resurfacing: an independent series. J Bone Joint Surg Br, 94(9): 1180-6, 2012.
- Van Der Straeten, C.; Van Quickenborne, D.; De Roest, B.; Calistri, A.; Victor, J.; and De Smet, K.: Metal ion levels from well-functioning Birmingham Hip Resurfacings decline significantly at ten years. Bone Joint J, 95-B(10): 1332-8, 2013.
- AOANJRR: Annual Report 2016. In AOA NJRR Annual Report. Edited by Graves, P. S., Adelaide, 2016.
- Shimmin, A. J.; Walter, W. L.; and Esposito, C.: The influence of the size of the component on the outcome of resurfacing arthroplasty of the hip: a review of the literature. J Bone Joint Surg Br, 92(4): 469-76, 2010.
- Van Der Straeten, C., and De Smet, K. A.: Current expert views on metal-on-metal hip resurfacing arthroplasty. Consensus of the 6th advanced Hip resurfacing course, Ghent, Belgium, May 2014. Hip Int, 26(1): 1-7, 2016.
- Beaule, P. E.; Campbell, P.; Lu, Z.; Leunig-Ganz, K.; Beck, M.; Leunig, M.; and Ganz, R.: Vascularity of the arthritic femoral head and hip resurfacing. J Bone Joint Surg Am, 88 Suppl 4: 85-96, 2006.
- Beaule, P. E.; Campbell, P.; and Shim, P.: Femoral head blood flow during hip resurfacing. Clin Orthop Relat Res, 456: 148-152, 2007.
- Beaule, P. E.; Harvey, N.; Zaragoza, E. J.; LeDuff, M.; and Dorey, F. J.: The femoral head/neck offset and hip resurfacing. J Bone Joint Surg Br, 89(1): 9-15, 2007.
- Grammatopoulos, G.; Pandit, H.; Murray, D. W.; and Gill, H. S.: The relationship between head-neck ratio and pseudotumour formation in metal-on-metal resurfacing arthroplasty of the hip. J Bone Joint Surg Br, 92(11): 1527-34, 2010.
- Grammatopoulos, G.; Pandit, H.; Glyn-Jones, S.; Lardy-Smith, P.; Gundle, R.; Whitwell, D.; Gill, H. S.; and Murray, D. W.: Optimal acetabular orientation for hip resurfacing. J Bone Joint Surg Br, 92(8): 1072-1078, 2010.
- Zylberberg, A. D.; Nishiwaki, T.; Kim, P. R.; and Beaule, P. E.: Clinical results of the conserve plus metal on metal hip resurfacing: an independent series. J Arthroplasty, 30(1): 68-73, 2015.
- Tice, A.; Kim, P.; Dinh, L.; Ryu, J. J.; and Beaule, P. E.: A randomised controlled trial of cemented and cementless femoral components for metal-on-metal hip resurfacing: a bone mineral density study. Bone Joint J, 97-B(12): 1608-14, 2015.
- Desloges, W.; Catelas, I.; Nishiwaki, T.; Kim, P. R.; and Beaule, P. E.: Do revised hip resurfacing arthroplasties lead to outcomes comparable to those of primary and revised total hip arthroplasties? Clin Orthop Relat Res, 470(11): 3134-41, 2012.
- De Smet, K. A.; Van Der Straeten, C.; Van Orsouw, M.; Doubi, R.; Backers, K.; and Grammatopoulos, G.: Revisions of metal-on-metal hip resurfacing: lessons learned and improved outcome. Orthop Clin North Am, 42(2): 259-69, ix, 2011.
- Grammatopoulos, G.; Pandit, H.; Kwon, Y. M.; Gundle, R.; McLardy-Smith, P.; Beard, D. J.; Murray, D. W.; and Gill, H. S.: Hip resurfacings revised for inflammatory pseudotumour have a poor outcome. J Bone Joint Surg Br, 91(8): 1019-24, 2009.