BMHR

Information from Dr. Bose at the Asian Regional Center for Hip Resurfacing

Introduction:

The Birmingham Mid Head Resection prosthesis is a recently developed hip prosthesis for patients who are keen on having metal on metal hip resurfacing but do not have enough bone stock in their femoral head to accept a resurfacing implant. The BMHR, by its resection level is suitable for these patients thereby opening an avenue for these patients to benefit from the resurfacing technology.

Asian regional center for hip resurfacing is the only center in Asia where currently BMHR surgeries are being performed. Dr. Vijay C. Bose of ARCH is one of the very few surgeons in the world to perform this surgery.

 

Concept:

It was increasingly becoming obvious that some younger active patients were not candidates for resurfacing due to some technical issues. In these patients only a stemmed component was possible by removing bone stalk. The new BMHR –Birmingham Mid Head Resection device is the ideal prosthesis for this patient group as it retains almost all the advantages of resurfacing. It is feasible even in patients who have large cysts or other structural abnormalities of the proximal femur.

 

The BMHR Prosthesis:

The acetabular component of the Birmingham Mid Head Resection prosthesis is the same as that of the BHR prosthesis. The femoral side is constituted by two modular components - a stout stem with a fusicone contour in the proximal portion and anti – rotation splines at the distal end . The special BMHR head goes over the taper adapter present at the top.

 

Current Indications

The Birmingham Mid Head Resection Prosthesis( BMHR) is used in the following clinical conditions -

• Avascular necrosis of the femoral head with significant bone loss.
• Femoral neck deformity (Valgus neck, Femoral Head Retroversion)
• When the cysts in the femoral neck are large, hip resurfacing cannot be performed. The BMHR is the choice of implant for such patients.
• This implant is suitable for abnormal pathologies like Perthes and SUFE.

Benefits and comparison:

• The BMHR prosthesis does not violate the femoral canal. Hence it can be revised to total hip replacement if required at a later stage.
• Loading at the head and neck junction is similar to BHR hence the benefits of BHR prosthesis also applies to the BMHR.
• Recent finite element analysis studies have proven that the load distribution in BHR is very similar to that of BMHR.

What is the BMHR and Why do we need it?

View Youtube Video about BMHR by Mr. McMinn by click below:

BMHR Video Part 1

BMHR Video Part 2

BMHR Video Part 3

Derek McMinn talks about the Birmingham Mid Head Resection prosthesis and its applied use in patients with Avascular Necrosis.

For patients with osteonecrosis involving a larger volume of the femoral head, an uncemented short-stemmed prosthesis, the Birmingham Mid Head Resection, BMHR, (MMT Ltd, Birmingham, United Kingdom, now Smith and Nephew Orthopaedics Ltd, Bromsgrove, United Kingdom) was developed.

Mr. McMinn has implanted about 40 BMHRs to date March 2008.

Illustration showing the three types of prostheses implanted in patients with femoral head avascular necrosis