UNITED STATES DISTRICT COURT 

NORTHERN DISTRICT OF INDIANA 

SOUTH BEND DIVISION 

IN RE: BIOMET M2a MAGNUM HIP ) 

IMPLANT PRODUCTS LIABILITY ) 

LITIGATION (MDL 2391) ) CAUSE NO. 3:12-md-2391 

) 

) 

This Document Relates to All Cases ) 

) 

AMENDED EXPLANT PRESERVATION ORDER

The Court ORDERS, effective immediately, that Defendants and Plaintiffs (collectively, the 

“Parties”) shall comply with the following directives relating to the preservation of explanted metalon-metal hip prostheses in the above-captioned case. This order does not address or resolve issues 

relating to admissibility under FED. R. EVID. 702, or any other state or federal rules of evidence or 

procedure. 

I. DEFINITIONS 

A. Biomet Devices Subject to this Order

The provisions of this order shall pertain to the following: 

1. “M2a Device” means the following Biomet M2a Hip System Device and 

components marketed and sold by defendants to plaintiffs in the United 

States: M2a Magnum and M2a 38. 

2. “Explanted M2

a Device” means the M2a Device explanted from a plaintiff in 

this litigation, and tissue samples, if any, that were retrieved during the 

explant surgery. 

II. RETRIEVAL ANALYSIS PROTOCOL

Pursuant to Section 522 of the Federal Food, Drug, and Cosmetic Act, 21 U.S.C. § 360l, 

Biomet is required by the Food and Drug Administration (“FDA”) to conduct post-market 

surveillance on the M2

a Devices at issue in this litigation (“Section 522 Postmarket Surveillance”). 

“Biomet’s Retrieval Analysis Protocol,” attached hereto as Exhibit A, represents a reasonable 

protocol (though not necessarily the only reasonable protocol) designed to enable preservation and 

analysis of Explanted M2

a Devices and surrounding tissues. 

Any initial inspection and analysis shall be non-destructive except to the extent Biomet 

might be required to conduct destructive testing under the Biomet Retrieval Analysis Protocol set 

forth in Exhibit A. Neither party will conduct destructive testing on an Explanted M2

a Device 

without prior written consent of the other party or by order of this court. A party intending on 

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performing destructive testing shall provide written notice of said intention to the opposing counsel 

set forth in Paragraph VIII herein and to the opposing party’s Lead MDL Counsel. If the party 

seeking destructive testing does not receive any objection to said destructive analysis within 30 days 

of issuing the initial notice in writing, that party may proceed. Any disagreement between the parties 

regarding destructive testing shall be resolved by the court. 

Reasonable compliance with Biomet’s Retrieval Analysis Protocol, or another retrieval 

analysis protocol that is non-destructive and consistent with methods and practices accepted by those 

in the field of the inspection and testing of orthopaedic devices, and with this Order shall not 

constitute spoliation of evidence. 

III. OBTAINING EXPLANTED M2

a DEVICES

A. M2

a Devices that have not been Explanted or are not in Either Party’s Possession 

With respect to M2

a Devices that have not yet been explanted or have been explanted but are 

not in either party’s possession, counsel for a plaintiff may elect to obtain plaintiff’s Explanted M2a 

Device from plaintiff’s surgeon or the hospital where the surgery occurred and send it to a contract 

laboratory of plaintiff’s choice or a designated storage facility. If plaintiff’s counsel does not elect 

to obtain an Explanted M2a Device within 60 days of the revision surgery, Biomet will make 

arrangements for it to be sent to Malcolm Naylor of Biomet in Warsaw, Indiana. 

The party that obtains the Explanted M2a Device shall comply with the requirement that the 

explant shall be preserved in accordance with either Biomet’s Retrieval Analysis Protocol or another 

retrieval analysis protocol used by an individual or institution in the field of orthopaedic device 

retrieval and analysis that uses a non-destructive method of explant retrieval and analysis. 

The Parties shall take reasonable measures to ensure that their respective contract 

laboratories and/or designated storage facilities maintain the Explanted M2a Devices, including all 

component parts, in the same condition as they were in when received, which includes refraining 

from altering the structure, existence, integrity, and nature of the device surfaces as explanted. 

B. Explanted M2

a Devices in a Party’s Possession

With respect to Explanted M2a Devices that were obtained by either party prior to the entry 

date of this Order: 

1. A party that has an Explanted M2a Device in its possession shall provide 

notice to the other party, including information as to the corresponding 

plaintiff’s name and surgeon, date of explantation, location of explant, and 

whether synovial fluid and/or whole blood/serum was retained. 

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2. To the extent that plaintiff’s counsel has a reasonable belief that Biomet, 

directly or indirectly through an independent distributor or associated third 

party, retrieved a plaintiff’s Explanted M2

a Device after removal, plaintiff’s 

counsel may send a written request to Biomet for information relating to the 

location and condition of said removed device components and any related 

pathology or specimens. Biomet shall undertake a reasonable search for the 

location of such plaintiff’s Explanted M2a Device and shall make good faith 

efforts to ensure the same is preserved consistent with this order including, 

refraining from destructive testing without notice and the opportunity to 

object. 

3. If a party inspected or tested an Explanted M2a Device that was obtained 

prior to the entry of this Order, the results of such inspection and testing shall 

be provided to the other party pursuant to this Order or the Parties’ mutual 

agreement. 

C. Access to Explanted M2

a Devices

A party has the right to obtain an Explanted M2a Device after the completion of inspection 

and testing by the other party’s contract laboratory(s) or expert(s). Each party shall make reasonable 

efforts to assure that its testing is completed within a reasonable amount of time. Upon written 

request and at the expense of the requesting party, after the completion of the inspection and testing 

of the Explanted M2a Device, the party in possession of the Explanted M2a Device shall send the 

device to the requesting party. Handling and packaging of the Explanted M2a Device by the plaintiff 

shall be performed either in accordance with Biomet’s Retrieval Analysis Protocol or in accordance 

with another retrieval analysis protocol that is non-destructive and consistent with methods and 

practices accepted by those in the field of the inspection and testing of orthopaedic devices. 

IV. RETRIEVAL AND ANALYSIS OF EXPLANTED M2a DEVICES

The procedures set forth in Biomet’s Retrieval Analysis Protocol represent one reasonable 

protocol for (1) retrieval, handling, and packaging of Explanted M2

a Devices; (2) the collection of 

clinical history of the plaintiff and the M2a Device; (3) collection of tissue and fluid samples near 

the M2

a Device; (4) photographic record of the Explanted M2a Device and tissues; (5) containing, 

labeling, cleaning, decontaminating, packaging, and shipping of retrieved implant, tissue, or fluid 

samples; (6) analysis of tissue and fluids; and (7) analysis of retrieved components. 

The Parties will not object to retrieval and analysis of an Explanted M2a Device that is either 

reasonably consistent with Biomet’s Retrieval Analysis Protocol or another retrieval analysis 

protocol that is non-destructive and consistent with methods and practices accepted by those in the 

field of the inspection and testing of orthopaedic devices and with this Order. 

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V. INSPECTION RESULTS

The Parties shall exchange all inspection and analysis results including data, 

photographs, and other information generated as a result of the retrieval and analysis 

of the Explanted M2

a Devices conducted pursuant to the Case Management Order of 

this court and this Order. The agreement to exchange the results of inspection and analysis 

does not require the exchange of drafts, privileged communications, or facts or opinions of 

a consulting expert employed for trial preparation. 

VI. COMPLIANCE 

A plaintiff shall make good faith efforts to ensure that non-party medical 

practitioners, hospitals, and vendors engaged to facilitate device preservation preserve his 

or her Explanted M2

a Devices that may be relevant to the claims, defenses, or subject matter 

of his or her case consistent with this order. The Defendants will not take steps that 

interfere with requests by or on behalf of a plaintiff to have the plaintiff’s surgeon and/or 

hospital retain and preserve any Explanted M2

a Device(s), tissue, or any other physical 

evidence. 

The Parties agree that they will not promote or encourage third parties, including, 

but not limited to, physicians and hospital personnel, to act in a way that is inconsistent 

with this Order. 

To the extent an explanted Biomet metal-on-metal device and any surrounding 

tissues has been preserved, but no longer needs to be retained for litigation purposes by a 

plaintiff, the device and surrounding tissue should be delivered to Biomet. The cost of 

transporting the device by Federal Express to Biomet will be paid by Biomet. Any 

plaintiffs’ counsel who is going to ship an explanted device to Biomet should coordinate 

with Biomet’s liaison counsel identified in this Amended Explant Preservation Order 

regarding the logistics of returning an explanted device to Biomet. 

VII. PROTOCOLS SHALL NOT BE BINDING

Neither party’s protocols for the retrieval, transport, storage, inspection, and 

testing of the M2

a Devices shall be binding on the other party. As long as either party’s 

protocols or practices for the retrieval, transport, storage, inspection, and testing of M2

a 

Devices are non-destructive and consistent with methods and practices accepted by those 

in the field of the inspection and testing of orthopaedic devices, that party shall be deemed 

to be in compliance with this Order, and those actions shall not constitute spoliation of 

evidence. 

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VIII. COURT OVERSIGHT

The process of obtaining Explanted Biomet M2a Devices from surgeons and 

hospitals and sending them to contract laboratories for inspection and testing is likely to 

involve complications that the Parties and this Court have not anticipated. To assist 

in the resolution of potential complications, the Court shall remain actively involved in 

this process, and the Parties shall keep the Court apprised, in writing, of encountered 

complications. In the event a dispute arises between a surgeon or hospital and a party or 

a party’s counsel regarding an Explanted M2a Device, the party’s counsel shall seek relief 

in this court, and this court will intervene, consistent with the Federal Rules of Civil 

Procedure, to resolve the dispute. To facilitate the Court’s involvement in resolving any 

complications arising from this Order, the Court designates Plaintiff’s Executive Committee 

Member Justin Presnal (JustinP@fisherboyd.com) of Fisher Boyd Johnson & Huguenard 

LLP, and Defendants’ Liaison Counsel John LaDue (jladue@lck-law.com) of LaDue 

Curran & Kuehn LLC as the contact persons who will field any questions and bring to the 

Court those issues requiring court involvement. 

SO ORDERED. 

ENTERED: November 24, 2015 

 

 /s/ Robert L. Miller, Jr. 

 Judge 

 United States District Court 

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Biomet’s Retrieval Analysis Protocol 

EXHIBIT A 

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1. SCOPE 

This document describes the protocol for the retrieval and analyses of Explanted Biomet 

Devices. The objective of this protocol is to enable preservation and analysis of Explanted 

Biomet Devices and surrounding tissues in a manner that may constitute evidence related to 

this litigation, as well as to permit Biomet to comply with its postmarket surveillance 

obligations pursuant to Section 522 of the Federal Food, Drug and Cosmetic Act, 21 U.S.C. 

3601. The investigation of the Explanted M2a Devices is non-destructive and will be 

performed on all reasonably available Explanted M2a Devices. 

2. REFERENCES 

ASTM F561 – 05a (Reapproved 2010): Standard Practice for Retrieval and Analysis of 

Medical Devices, and Associated Tissues and Fluids 

ISO 12891-1: 2011 Implants for surgery – Retrieval and analysis of surgical implants, Part 1: 

Retrieval and handling 

ISO 12891-2: 2000 Implants for surgery – Retrieval and analysis of surgical implants, Part 2: 

Analysis of retrieved metallic surgical implants 

ASTM E860 – 07: Standard Practice for Examining and Preparing Items That Are Or May 

Become Involved in Criminal or Civil Litigation 

ASTM E1188 – 05: Standard Practice for Collection and Preservation of Information and 

Physical Items by a Technical Investigator 

ASTM E620: Standard Practice for Reporting Opinions of Scientific or Technical Experts 

ASTM E678: Standard Practice for Evaluation of Scientific or Technical Data 

3. TERMS AND DEFINITIONS 

Metal on metal component: a component of a total hip replacement whereby the articulating 

surfaces of both the ball and socket are intended to be Co-28Cr-6Mo per ASTM F75 or 

F1537. 

Reasonably available retrieval: any Explanted M2

a Device obtained by a Party pertaining to a 

Plaintiff in this litigation. 

4. PROCEDURES FOR RETRIEVAL, HANDLING AND PACKAGING 

Institutional guidelines for the retrieval, handling and packaging of potentially infectious 

materials shall be utilized. In situations where institutional guidelines do not exist, the 

specifications outlined in ISO 12891-1 can be utilized. 

Specific requirements for this retrieval study: 

 When handling, packaging and shipping the retrieved components, the hospital or 

clinic should avoid putting all the components in the same container without 

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separating packaging. Ideally, each retrieved component should be individually 

wrapped and stored in its own container, then placed in a larger container with all the 

other retrieved components. This will prevent further damage to the explants, which 

can be difficult to distinguish from in situ damage. 

 Shortly after removal, a detailed record of any damage caused to the components 

during extraction should be performed, especially in the presence of the operating 

surgeon. Adequate ‘macro’ photography can also be helpful. This information should 

be labeled adequately and should accompany the explanted components. This will 

make it easy to differentiate between damaged regions caused in vivo and those caused 

during extraction. 

 It is imperative to label the retrieved parts adequately for future identification. 

 The retrieved components should be marked in a non-destructive way to indicate their 

orientation in situ before removal. If the implants are not marked before extraction or 

immediately after, then the true location of the wear scars can only be guessed. This 

can be avoided easily by marking the superior rim of the cup and the base of the 

femoral head. 

 Sterilization of metal on metal components should be performed utilizing cold 

techniques. Do NOT sterilize metal on metal components by steam autoclave as this 

may alter features or surfaces which may be essential in determining failure modes. 

o In situations where the device has already been sterilized by steam autoclave 

prior to coming into Biomet’s control, the investigator may still perform the 

retrieval analysis taking into consideration the potential confounding factors 

introduced by the steam autoclave procedure. 

o Where residual tissues are retained on or within the components, fixation by 

10% buffered formalin and/or ethanol and/or other fixative will be included 

in the sterilization procedure. 

5. COLLECTION OF CLINICAL HISTORY OF THE IMPLANT AND 

PATIENT 

Whenever possible, the clinical history of the Plaintiff and the Explanted M2a Device shall be 

obtained and recorded. 

This clinical history shall include at least the following, if available: 

 the name or identification number of the patient as permitted by HIPAA or other 

applicable national regulations; 

 the original diagnosis which resulted in the use of the surgical implant; 

 the identification of the components inserted, including part number and lot number; 

 an X-ray of the surgical implant in situ taken after the insertion operation; 

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 an X-ray of the surgical implant in situ taken prior to the retrieval operation; 

 the patient's activity level including the ability to perform work, sports and recreational 

activities; 

 metal ion analysis of blood or serum for levels of cobalt and chromium; 

 the patient's medical history relevant to the surgical implant, including the hospital or 

clinic at which the surgical implant was implanted; 

 information on the patient's experience with the surgical implant just before surgical 

implant retrieval including any audible noises emanating from the joint; 

 sex, height and weight of the patient; 

 the date of the insertion operation; 

 the date of the retrieval operation; 

 observations during the retrieval operation including stability of the cup or dark 

staining of the surrounding tissues; 

 the reason for explantation of the components; 

 the hospital or clinic at which the surgical implant was inserted; 

 the hospital or clinic at which the surgical implant was retrieved. 

The information obtained will be treated as confidential by the Parties. 

6. COLLECTION OF TISSUE AND FLUID SAMPLES NEAR THE 

IMPLANT 

In order to assist in the determination of the failure mode for the retrieval, it is recommended 

that local tissue and fluid samples are obtained during the retrieval operation. The general 

procedure for this collection is contained within section 3.4 of ISO 12891-1 which is 

excerpted below: 

Taking into account the need for patient safety, if tissue and/or fluid samples are to be collected for 

analysis, then these shall be retrieved in a manner which causes as little damage as possible to both the 

surgical implant and the tissues. 

For microbiological investigation, swabs, tissue and/or fluid samples shall be taken from a location 

adjacent to the implant as soon as possible after the surgical implant has been exposed. Where and how the 

specimens are taken shall be recorded. 

For histological examination, tissue samples shall be taken from a location adjacent to the implant and/or 

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from other relevant sites (e.g. lymph nodes or any tissue with abnormal appearance). When possible, tissue 

samples for histological examination shall include portions extending into the normal tissue. 

The site of the tissue excision and the orientation of the tissue relative to the surgical implant shall be 

indicated and recorded. Where possible, the proximal end of the tissue shall be marked (e.g. with a suture). 

Where necessary, the original length of the tissue shall be maintained (e.g. with plastic muscle biopsy clamps 

or by pinning the tissue to a corkboard or by other means, which avoid contact with metal which could 

corrode). 

The tissue samples for histological examination shall be transferred as early as possible to an appropriate 

fixative or other media. The type of fixative used and the time between excision and placement in the 

fixative or media shall be documented. The tissue sample shall be treated in a routine manner as required 

for histological examination, unless a special method is needed for special investigations. If appropriate, the 

media used to preserve tissue attached to a retrieved surgical implant shall be selected so as not to affect the 

surgical implant. When it is not possible to preserve the tissues without affecting the retrieved surgical 

implant, the portions of the retrieved surgical implant to be analyzed should be determined and the tissue 

preserved accordingly. 

Fluids obtained by aspiration shall be appropriately preserved for examination unless a special method is 

needed for special investigations. The preservation method should be chosen taking into account the intended 

analysis. 

7. PHOTOGRAPHIC RECORD OF THE EXPLANTED DEVICE AND 

TISSUES 

Where appropriate, photographic records shall be made of the surgical implant in situ, of the 

surgical site and of the explanted surgical implant and any associated tissue specimens. 

Where appropriate, the orientation of all removed surgical implant components in relation to 

each other and their placement in relation to the body and associated excised material shall be 

recorded. If not self-explanatory, the proximal end and the orientation in the transverse plane 

of the implant shall be marked and documented. Any observed abnormalities in the 

appearance or condition of the device shall be recorded. 

8. CONTAINING, LABELING, CLEANING, DECONTAMINATING, 

PACKAGING AND SHIPPING OF RETRIEVED IMPLANT, TISSUE, OR 

FLUID SAMPLES 

General instructions for labeling, cleaning, decontaminating, packaging and shipping of 

retrieved implants, tissue, or fluid sample are found in sections 3.6, 3.7, 3.8, 3.9, & 3.10 of ISO 

12891-1. 

In addition to these general instructions 

 When handling, packaging and shipping the retrieved components, the hospital or 

clinic should avoid putting all the components in the same container without 

separating packaging. Ideally, each retrieved component should be individually 

wrapped and stored in its own container, then placed in a larger container with all the 

other retrieved components. This will prevent further damage to the explants, which 

can be difficult to distinguish from in situ damage. 

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 Shortly after removal, a detailed record of any damage caused to the components 

during extraction should be performed, especially in the presence of the operating 

surgeon. Adequate ‘macro’ photography can also be helpful. This information should 

be labeled adequately and should accompany the explanted components. This will 

make it easy to differentiate between damaged regions caused in vivo and those caused 

during extraction. 

 It is imperative to label the retrieved parts adequately for future identification. 

 The retrieved components should be marked in a non-destructive way to indicate their 

orientation in situ before removal. If the implants are not marked before extraction or 

immediately after, then the true location of the wear scars can only be guessed. This 

can be avoided easily by marking the superior rim of the cup and the base of the 

femoral head. 

 Sterilization of metal on metal components should be performed utilizing cold 

techniques. Do NOT sterilize metal on metal components by steam autoclave as this 

may alter features or surfaces which may be essential in determining failure modes. 

 As soon as possible, ship the following: 

o Clinical information per section 5 

o Photographic records per section 7 

o Retrieved implants 

o Tissue or fluids, if applicable 

To the following address: 

 Clinical Studies – MOM Litigation Retrieval 

 Biomet Orthopedics 

 56 E. Bell Drive 

 Warsaw, IN 46582 

9. ANALYSIS OF TISSUE AND FLUIDS 

Analysis of tissue and fluids will be performed per ISO 12891 and/or ASTM F561. In 

addition to these protocols, an ALVAL histological score for the tissue shall be made pursuant 

to the following reference: 

Campbell P, Ebramzadeh E, Nelson S, Takamura K, De Smet K, & Amstutz HC, 

Clinical Orthopaedics and Related Research, 2010; 468(9):2321-7. 

*A number of new consensus standards are currently under development within ASTM 

committee F04. Where appropriate and reasonable, new standards will be considered for 

studies. 

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10. ANALYSIS OF RETRIEVED COMPONENTS – VISUAL ANALYSIS 

Visual analysis will be performed on all reasonably available retrievals. Visual analysis shall 

include the observation of the components with the unaided eye or with the aid of a 

stereomicroscope. If the retrieval contains more than one component, each component 

should be analyzed. The following information shall be recorded: 

 Unique retrieval code to identify the components 

 Catalogue and lot number of each component along with device description 

 Markings found on the implant, such as logos, part numbers, or lot numbers 

 Date of analysis 

 Date retrieved 

 Implant duration, if available 

 Reason for explantation, if available 

Examination of the component will include all surfaces of the components looking for 

evidence of in service or iatrogenic damage. The following features shall be documented for 

presence, size/area, location, and severity/degree: 

 Bearing surface(s) 

o Wear 

o Scratches 

o 3rd body damage 

o Corrosion 

o Embedded particles 

o Discoloration or staining 

o Impingement 

o Edge damage/subluxation 

o Equatorial contact 

o Stripe wear formations, both superior and inferior stripes on cup and head 

o Evidence of, or exclusion of, a polished main wear zone 

o Surface pitting 

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o Wear scars exceeding to the cup rim and beyond 

 Taper junction(s) 

o Fretting 

o Corrosion 

o Discoloration or staining 

o Evidence of head or adapter stuck on neck taper 

 Non-bearing surfaces 

o Cup front face damage 

o Cup edge/rim damage, both superior and inferior edges 

o Backside damage, i.e. any damage to the backing of the cup (e.g. removal of 

porous coating) or bottom face of the femoral head 

o Fretting damage caused by fixation screws, if present 

The location of these features will be indicated by performing concise wear mapping of the 

worn features on both articulating and non-articulating surfaces. 

11. ANALYSIS OF RETRIEVED COMPONENTS AND RECORDS – 

PHYSICAL ANALYSIS 

If the following minimal clinical history/information is available: 

 Date of implantation 

 Date of explantation 

 X-rays 

o Post-operative 

o Prior to explantation 

 Cup inclination 

 Cup anteversion 

 Sex, Height and weight of patient 

 Activity level of patient 

and after patient consent has been obtained, the following physical analyses will be 

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performed: 

 If an explanted device is determined to have been well-positioned in situ and is 

associated with adverse tissue reactions, or has obvious high wear/damage, then every 

effort should be made to estimate the total volumetric wear from the explanted 

components. A suggested technique includes a three-dimensional coordinate 

measuring machine (CMM) to measure changes in component radius of curvature of 

both worn and unworn surfaces. Estimations of volumetric wear can then be 

determined using 3D modeling software. 

 Surface roughness measurements of damaged and undamaged Co-Cr-Mo surfaces, 

including at least: average roughness (Ra or Sa), surface texture (Rz or Sz), maximum 

scratch height (Rp or Sp) and skewness (Rsk or Ssk), plus be accompanied by close-up 

photographs for each measurement site to provide a visual indication of the amount of 

wear that took place and what wear processes were involved 

 Scanning electron microscopy to examine microstructural features such as topography, 

carbide morphology, grain structure (if visible), along with EDS to determine surface 

chemistry, for both the bearing surfaces and the taper junction. The analysis should 

include investigation of any material transfer, embedded debris or corrosion product 

on the surfaces. 

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