A prospective, single arm, open label study assessing the
performance and safety of the Birmingham Hip Resurfacing
system in relatively young males with primary arthritis of the
hip requiring hip replacement.

The Birmingham Hip Resurfacing (BHR) prosthesis (manufactured by Smith &
Nephew) is a so-called Metal-on-Metal (MoM) prosthesis that was released in the
market 15 years ago and is successfully implanted worldwide ever since. MoM is
very durable and therefore ideal for the relative young, active patients with
an end stadium of primary arthritis of the hip. These type of patients have
high demands on their new hip prosthesis.
Because of the success of the BHR hip prosthesis, many orthopaedic
manufacturers have developed and marketed similar prostheses. Unfortunately
these prostheses appeared to be of incorrect design. Also in the Netherlands
these erroneous prostheses have been implanted, including the ASR (Johnson &
Johnson) and MoM total hip prosthesis (THP, Biomet) and have been implanted in
high numbers. Due to the failure of these prostheses the MoM technology has
received a lot of negative publicity in the Netherlands. The Dutch Orthopaedic
Association (NOV) has reacted to this publicity by issuing a guideline to her
members regarding the use of MoM prostheses.

However, various publications and national registries, including those from
England & Wales and Australia, show that the BHR is a safe and good hip
prosthesis, provided that it is well placed (see 2.6) with the correct
indication (Murray, 2012) (Holland, 2012) (Treacy, 2011) (Matharu, 2013 ).
Looking at the group of demanding patients, who currently receive a traditional
total hip, the BHR would perform even better (Baker, 2011). Also, the BHR is
compliant with the benchmark of the National Institute for Health and Clinical
Excellence (NICE); a revision level of less than ten percent after ten years
for primary THP (Weegen, 2011). In a recent review (Haddad, 2011) of MoM hip
implants, the BHR shows the lowest failure rates compared with other MoM
implants.

In this paper (Haddad, 2011) the authors also emphasize that the result of MoM
hip resurfacing largely depend on appropriate surgical technique and patient
selection. Also, current data suggests that correct surgical technique in an
appropriate selected cohort of patients is associated with a low incidence of
adverse soft-tissue reactions. High-risk factors for developing complications
include small component sizes, female gender and significant anatomical
variations due to for example, dysplasia, where positioning may be difficult.

The advice of the NOV of January 17 2012 indicates that there is still a
possibility to use MoM-prostheses, provided that they are implanted within the
setting of a clinical trial that complies with GCP (see attachment I).

With this study we are aiming to confirm that the BHR is indeed a safe implant,
when used in an appropriately selected patient group and when implanted with
the appropriate surgical technique.
Therefore, only patients with a primary diagnosis of arthritis of the hip will
be included and female patients and males with a small femoral head size will
be excluded. Besides that, the performing orthopaedic surgeon and investigator
has exceptional experience in resurfacing procedures with the BHR system (see
2.6).
Combined with the extensive safety measures in this protocol we provide a safe
and beneficial environment for the selected study patients.

The primary objectives of this study are to assess the performance of the
Birmingham Hip Resurfacing in young active men with large femoral heads as
measured with the Oxford Hip Score (OHS) and to evaluate the safety of this
device as assessed by the incidence of complications of hip resurfacing.

This is a non-randomized, interventional study with a CE marked device.
Patients are followed up to 10 years and annually x-ray images are made,
physical examination is done and blodd will be drawn (to determine cobalt
levels). Besides that, the patients are requested to complete 3 questionnaires
annually (HOOS, EQ-5D and OHS). At 1, 5 and 10 years post-operative an MRI and
utrasound imaging of the hip will be done for additional checks on device
related adverse events.
In case the patients has any complaints that could be in any way related to the
device or if there are any findings on the x-ray images, further assessments
will be done to check for device related adverse events.

The selected patient group in this study is already qualfied for a hip
replacement. The intervention in this trail is the implantation of the BHR
resrurfacing implant instead of the standard total hip replament implant.

Burden:
Since only patienst are included who are in need of a hip replacement only the
study specific burden is lised below:
- During the annual visits blood is drawn for determination of cobalt levels.
- Pre-operatively and annually post-operatively patients are requested to
complete 3 questionnaires.
- During the 1, 5 and 10 year post-operative visits an MRI scan and ultrasound
imaging will be done to identify any incipient adverse device effects.
It is anticipated that the annual visits will take about 0,5-1 hour more than
usual.

Risks
The related risks can be categorized into 3 categories: general surgery
related, general hip replacement related and specifically device related.
Since all patients will undergo a hip replacement anyway, only the specific
device related risks are listed below:
Risico's
- Adverse reactions to metal debris (ARMD)
- Peri-prosthetic aseptic lymphocyte dominated vasculitis associated lesions
(ALVAL)
- Soft tisue masses (pseudotumoren)
- Avascular necrosis
- Femoral neck fractures

In the group of patients included in this study the above mentioned adverse
events are rare. This specific patient group is relatively young and are still
very active and therefore have high demands on a prosthesis. The BHR prosthesis
is very wear resistant and in case a future revision is needed (due to the
relatively young age a lot of patients outlive their prosthesis) it will be
much easier compared to a initial total hip prothesis (because the femoral head
is left in place and no femoral shaft is used).