HIP RESURFACING
Hip Resurfacing
Hip resurfacing is a recent technology which is being used in young patients who needs a hip replacement. In a conventional total hip replacement the ball of the hip joint is cut along with the neck of the femur and is replaced by a metal implant. In hip resurfacing the ball of the hip joint is preserved to a large extent and is only reshaped to fit a metal cap. The femoral neck is not cut.
The main potential advantage in hip resurfacing is that there is preservation of bone stock for further revision surgery. Another potential advantage is that once the soft tissues have healed there is very less chance of hip dislocation because of the large size of the ball (compared to conventional total hip replacement) and they can lead an active lifestyle with very little restriction.

Hip Resurfacing

Conventional Total Hip Replacement
However, hip resurfacing has its own special issues compared to a conventional total hip replacements including that it is technically more difficult procedure, higher early failure rate and increased metal ion levels in the blood. Special complications include fracture of the femoral neck, femoral neck thinning, avascular necrosis of the resurfaced femoral head (due to decreased blood supply), increased risk of heterotopic ossification (new bone formation in the muscle) and metal ion related problems.
Computer guided hip resurfacing: Studies have shown that correct placement of the femoral component is important decrease the risk of femoral neck fractures following hip resurfacing. The accuracy of placement can be improved by using computer guidance. Mr. Ganapathi’s has published a study comparing the difference between the preoperative planned position and postoperative position. The study showed that computer navigation had a significantly lower error compared to manual placement. Mr. Ganapathi uses computer navigation routinely when doing hip resurfacing.
In addition, options are now available to use the large metal on metal bearings in a conventional type total hip replacements (which will provide the same stability but with lesser risk of early complications like femoral neck fractures (large head diameter total hip replacements).
Large Diameter Head & Hip Replacement
Metal ion issues: More recently a study from Oxford1 has reported cases of excessive fluid collection around the resurfaced hip with damage to the surrounding tissues in some patients (so called “pseudotumours”. The reasons are not entirely clear at this stage and may be related to allergic reaction or excessive metal ion/particles. Many factors have been associated with this including females, smaller components and placement of the components as well as the implant design and materials.
However, many centres have reported excellent results in men with larger components and there is also conflicting evidence regarding the influence of the gender. For example in the Australian national joint registry, the is higher failure in females. There are other studies suggesting the component size is more important than the gender. 3,6
Australian Joint Registry report (2009) showing higher failure rate in females
but good result in men
Very recently MHRA issued an alert on metal on metal bearings with advice about regularly following up patients and monitoring the outcome.
In light of the above factors, although hip resurfacing was used very frequently in young adults few years ago, more recently the patient selection has become more important. It is also important to understand that all type of hip replacements have some advantages and disadvantages and selecting the type of hip replacements essentially depends on the balance between potential advantages and disadvantages. It is important that a decision about hip resurfacing is made on an individual basis after discussing the benefits and risks with the patient.
To maintain the advantage of the large diameter bearing (better range of movement and better stability) while minimising the potential adverse effects of metal ions, implant companies are adopting various strategies. They include surface modification of the metal surface (which has been shown to have low metal ion levels in recent studies) and using ceramics as large diameter bearing option. Mr.Ganapathi would be happy to discuss with you regarding these newer developments and would be able to offer those options if appropriate.
Scientific Literature
The following are some relevant selected scientific references:
1. Risk factors for inflammatory pseudotumour formation following hip resurfacing.
J Bone Joint Surg Br. 2009 Dec;91(12):1566-
Glyn-
Department of Orthopaedics, Nuffield Orthopaedic Centre, University of Oxford, Oxford, England.
Abstract: Metal-
2. Canadian academic experience with metal- on- metal hip resurfacing.
Bull NYU Hosp Jt Dis. 2009;67(2):128-
O’Neill M, Beaule PE, Bin Nasser A, Garbuz D, Lavigne M, Duncan C, Kim PR, Schemitsch E.
Abstract: The current depth and breadth of experience in hip resurfacing in Canadian academic centers is not well known. This study endeavors to increase awareness of the prevalence of programs and current experience in a select number of representative teaching centers by examining the learning curve of high-
3. Sex as a Patient Selection Criterion for Metal- on- Metal Hip Resurfacing Arthroplasty.
J Arthroplasty. 2010 May 7. [Epub ahead of print]
Amstutz HC, Wisk LE, Le Duff MJ.
Joint Replacement Institute at St. Vincent Medical Center, Los Angeles, California.
Abstract: Short-
4. Eleven years of experience with metal- on- metal hybrid hip resurfacing: a review of 1000 conserve plus.
J Arthroplasty. 2008 Sep;23(6 Suppl 1):36-
Amstutz HC, Le Duff MJ.
Joint Replacement Institute at St Vincent Medical Center, Los Angeles, California 90057, USA.
Abstract: Hip resurfacing is currently the fastest growing hip procedure worldwide. We reviewed 1000 hips in 838 patients who received a Conserve Plus (Wright Medical Technology, Inc., Arlington, Tenn) resurfacing at a single institution. The mean age of the patients was 50.0 years with 74.7% male. The hips were resurfaced irrespective of femoral defect size or etiology. The mean follow-
5. Birmingham hip resurfacing: Five to eight year results.
Int Orthop. 2010 Jun 19. [Epub ahead of print]
Reito A, Puolakka T, Pajamäki J.
Abstract: Hip resurfacings have been performed in our hospital since May 2001, and in this retrospective study, we analysed the clinical and radiological outcome of the first 144 prostheses (126 patients). One hundred and seven patients have visited our hospital for regular follow-
6. The influence of head size and sex on the outcome of Birmingham hip resurfacing.
J Bone Joint Surg Am. 2010 Jan;92(1):105-
McBryde CW, Theivendran K, Thomas AM, Treacy RB, Pynsent PB.
Abstract: BACKGROUND: Hip resurfacing has gained popularity for the treatment of young and active patients who have arthritis. Recent literature has demonstrated an increased rate of revision among female patients as compared with male patients who have undergone hip resurfacing. The aim of the present study was to identify any differences in survival or functional outcome between male and female patients with osteoarthritis who were managed with metal-
7. Birmingham hip arthroplasty: five to eight years of prospective multicenter results.
J Arthroplasty. 2009 Oct;24(7):1044-
Khan M, Kuiper JH, Edwards D, Robinson E, Richardson JB.
Abstract: Pioneering centers report excellent results of Birmingham resurfacing arthroplasty. Results from pioneering surgeons are not usually reproduced when implants are used at other centers. We therefore studied patients’ satisfaction, postoperative hip function, and survival of Birmingham hip resurfacing in a group, operated by nonpioneering surgeons. The median first year postoperative Harris hip score was 95, and this score was sustained for a period of 8 years. The cumulative survival at 8 years was 95.7%. Most of the failures were in the first year; commonest cause of the first year failures was fracture of femoral neck. This complication is not seen as a substantial problem in the pioneering surgeons’ studies. We therefore conclude that this complication is not related to the prosthesis and that its occurrence can be reduced.
8. Birmingham hip resurfacing arthroplasty. A minimum follow- up of five years.
J Bone Joint Surg Br. 2005 Feb;87(2):167-
Treacy RB, McBryde CW, Pynsent PB.
Royal Orthopaedic Hospital, Birmingham, England.
Abstract: We report the survival at five years of 144 consecutive metal-
9. What is the Midterm Survivorship and Function After Hip Resurfacing?
Clin Orthop Relat Res. 2010 Jun 24. [Epub ahead of print]
Rahman L, Muirhead-
The London Hip Unit, 30 Devonshire Street, London, W1G 6PU, UK
Abstract: BACKGROUND: Hip resurfacing arthroplasty is a common procedure that improves functional scores and has a reported survivorship between 95% and 98% at 5 years. However, most studies are reported from the pioneering rather than independent centers or have relatively small patient numbers or less than five years followup. Various factors have been implicated in early failure. QUESTIONS/PURPOSES: Our purposes were to determine: (1) the midterm survival of the BHR; (2) the function in patients treated with hip resurfacing; and (3) whether age, gender, BMI, or size of components related to failure. METHODS: We reviewed the first 302 patients (329 hips) on whom we performed resurfacing arthroplasty. We assessed the survivorship, change in functional hip scores (HHS, OHS, WOMAC, UCLA), and analyzed potential risk factors (age, gender, BMI, component size) for failure. The mean age at the time of surgery was 56.0 years (range, 28.2-