Clinical Studies update January 2018 ID: NCT02503891



The MP-1™ Acetabular liners are intended to be used only against ceramic

femoral heads- Biolox Delta™

January 2018

THIRD CLINICAL STUDY will start in 1Q/ 2018 in a third Medical Center at in Haemeq Hospital in Afula Israel. This study will include 50 patients.

September 2017

SECOND CLINICAL STUDY begun in the 9/ 2017 in a second clinical center at Rambam hospital in Haifa Israel. This study will include 15 patients.

3 cases were already completed.

January 2013

FIRST CLINICAL Study started in New Zealand with Ethical Committee approval for  100 CASES and is ongoing.

So far, 77 patients were included in the clinical trial.    The follow-up showed 100% success.

The surgery was performed for the first time on young patients aged 42-45.

The surgeries were conducted by Dr James Burn FRACS , specialist orthopedic surgeon, in Christchurch, New Zealand.

Up-to-date all patients were released from hospital after 4 days. All primary and secondary endpoints   clinical results are excellent with no adverse events

The COBRA research group provided the funding. Cobra is in charge of the regulatory aspects and clinical support.

The clinical database is held securely in NZJR (New Zealand Joint Register).

Reports are available from the Ethics Committee at agreed timetables.







Improvement in Oxford Score after 2 years implantation


Ms. P C 63 years old

Patient History:

OLD – Ceramic head on Enduron(PE) Liner:

25.2.97 Bilat OA of the hips

6 .10.98 Left Total Hip Replacement Spectron cemented stem size 2 high offset with +4 mm 28 mm zirconia ceramic head

(S and N) and Duroloc 50 mm OD./ Enduron pressfit cup (J & J)

4.5.99 Right THR Spectron cemented stem, Zirconia 28 mm head, Duraloc 50 mm cup and Enduron liner.

23.9.05 wear was demonstrated in follow up films. Heads eccentric in acetabulum.

28.2.06 Revision of right hip to Reflection alumina ceramic on ceramic 32 mm articulation and new stem re-cemented in the same cement mantle and grafting of the defects medially with washed femoral head allograft. Partial weight bearing for 2 months due to the extent of bone loss medially. Cement used, Simplex antibiotic (Stryker)

NEW – Ceramic head on MP-1™ Acetabular Liner:

20.11.06   Revision of the left hip to new Spectron Stem ,Alumina ceramic Biolox head with a 52 Refection shell (Smith &Nephew) with 32 mm ID and MP-1™ POLYIMIDE LINER. Cement as above.

Histology showed no infection (only polyethylene debris from the previous surgery) and
5 day cultures was all clear for infection.

Patient discharged home after 3 days post operation and doing well.  Was reviewed at 5 weeks. No transfusion required and patient weight bearing 50% for first 5 weeks.

6 months Follow up- 6.4.07

Blood test result – Excellent results

X-RAY – Excellent results

3 years follow up -29.10.09

Blood test result – Excellent results

X-RAY –excellent results (see below)

Harris Score – excellent results

X- RAY Follow up – 3 years, the MP1™ liner is on the left side.

6 years Follow up- 6.10.12

Blood test result – Excellent results

X-RAY – Excellent results

Harris score: 100


Post THRs bilaterally. Routine follow up.


Acetabular and femoral components of the bilateral THRs and bilateral acetabular screws remain good and unchanged position.

Minimal lucency related to the right femoral component proximally is stable.

No evidence of interval complication seen.

9 years follow up -29.10.15

Blood test result – Excellent results

X-RAY –excellent results

Harris Score – excellent results


Mr. I D A, 65 DOB: 23.05.1943 CHRISTCHURCH

Accident (10.07.00) – Right femur femoral neck fracture

05.09.07 OPERATION

OPERATION: Removal of right CHS and anti rotation screw -conversion to total hip replacement Synergy STEM /Reflection SHELL/ ceramic BIOLOX S&N /MP-1 polyimide

Surgeon: James Burn Anesthetist: Mr. C O

Hospital: Burwood Hospital

PROCEDURE: General anesthetic. Patient positioned right side up. The hip was exposed through a posterior approach extending into the old scar. The CHS plate and screws were removed. They were very tight and there was an asnis screw, which had to be taken out with pliers due to non-availability of any suitable screwdrivers for this particular implant in Christchurch. The hip was dislocated prior to the final removal of the metal ware to make sure there was no spiral fracture risk of the femur. The capsule was released anteriorly and the neck resected, it was collapsed right down due to the avascular necrosis of the head. The leg was short about 12-5mm. The acetabulum was reamed to 50 and deepened at 49 and a 50 Reflection ceramic shell was inserted. New trial liner used, the femur was reamed up to take a Size 13 high offset Synergy stem. The range of motion was checked with a standard head Size 32 and then the definitive polyimide liner 50 was inserted, the 32 ceramic biolox forte Smith and Nephew head was then applied. The hip was stable in all positions. The capsule was repaired posteriorly with fibrewire through trans osseous sutures using the Star drill. The leg was lengthened approximately 11 mm and no change in off-set. Closure over two Lovac drains. Patient has got arterial disease and is for Clexane 20mg daily, Aspirin and foot pumps.

Report from Surgeon: Dr. P. James Burn FRACS

Mr. A is a 65 yr. old retired air traffic controller who sustained a subcapital fracture of his right femoral neck on 10 July 2000. He underwent a compression hip screw fixation at the time. This healed but he was left with a shortened right leg of 10 mm and an arthritic hip. Cement less total hip replacement was recommended by myself.

He was offered a ceramic on ceramic hip and as well the possibility of having the 2nd polyimide on ceramic articulation total hip replacement in the world. He chose the latter to help medical science understanding that there were no known toxic effects in animals, but that the tissue response of wear products was unknown, and should this occur he would be changed to ceramic on ceramic.

Surgery was uncomplicated, but his hip was stiff and required lengthening. No modification to a standard surgery or rehabilitation was made. He noticed an occasional “squeak” from his hip in the first 2 weeks and this has disappeared. I postulate this being due to the hip being tight and poor lubrication from no micro-separation occurring. This disappeared and has not returned.

6 months Follow up

A CT scan was done at 6 months post operatively. This was in response to the patient having some buttock pain which subsequently was considered to be referred from the lower lumbar spine.

The CT scan shows the holes in the acetabular cup for screws ( Smith and Nephew Reflection FSO for ceramic inserts) which have no “blanking” caps. No osteolysis is seen though this is very early but promising.

The patient continues to be asymptomatic with no restrictions and remains under close clinical follow-up. The 9-month blood results are normal apart from a marginally raised gamma GT at 57 IU/L (n 0-50)

1 Year Follow up -29.10.08

Excellent Blood test results.

X-RAY –Excellent results

2 years follow up – 14.9.09

Excellent blood tests results

X-RAY –Excellent results

Harris score 100 out of 100.

Clinical report – video film demonstrating excellent walking and climbing steps

5 years follow up – 14.9.12

Excellent blood tests results

X-RAY –Excellent results

Harris score 97 out of 100.

Blood screening (screen, LFTs,U&E, RFTs and CRPs), serial radiographic weight-bearing films, Modified Harris Hip scores and Oxford Hip scores. There have been no features to suggest particle disease and osteolysis, or interference with osseointegration. Wear on magnified weight bearing radiographs is not seen.

Video film demonstrating excellent walking and climbing steps

The second patient passed away on 2014 from heart disease (not connected to the implant).

He donated his body to the science.

Histology results after 6.5 years of implantation showed:

  • No Osteolysis,
  • No osteoclasts
  • No measurable wear
  • The soft tissues around the hip were very bland without fibrosis or reactive macrophages.

The CT scan of the specimen showed:

  • No osteolysis even through the cup screw holes.

The MP1 liner implant was undamaged and had no dimensional change after 6.5 years.

Adjacent bone X4 power:

“The adjacent bone shows” minimal remodeling of the cement lines but is essentially normal.