HR Issues

Pseudotumours Risk For Hip Resurfacing Highlights Need For Regular Clinical Follow-up For New Devices

Link  http://www.medicalnewstoday.com/articles/114601.php

July 11, 2008

As the incidence of metal-on-metal hip resurfacing has increased in recent years, especially in younger patients, research published in the Journal of Bone and Joint Surgery - British Volume (JBJS-Br) discusses occurrences of "pseudotumours" as a result.

The researchers estimate that approximately 1% of patients who have metal-on-metal hip resurfacings develop pseudotumours within five years of treatment. A pseudotumour is 'a soft-tissue mass associated with the implant…neither malignant nor infective in nature', but that causes pain and discomfort to the patient.

Most worryingly for patients and doctors is that the causes of the tumours are unknown. The research discusses possible causes including 'toxic reaction to an excess of particulate metal wear debris.' The article stresses the need for further research to be done into the incidence of pseudotumours in patients who have had this treatment.

The paper concludes that the incidence of pseudotumours must be related to metal-on-metal hip resurfacing highlighting 'the need for regular clinical follow-up for new devices'. Such follow-up would follow NICE recommendations, but the current NHS climate makes this difficult, if not impossible, to achieve.

Read the research abstract

Notes

- The Journal of Bone and Joint Surgery - British Volume is a world leading orthopaedics journal with an Impact Factor of 1.868

- JBJS-Br publishes twelve issues a year of high-quality, peer-reviewed research, overseen by an international editorial board led by Editor James Scott

- The Journal was first published in 1948 by The British Editorial Society of Bone and Joint Surgery, a registered charity (No. 209299), with the object of the advancement and improvement of education in orthopaedic surgery and allied branches of surgery and the diffusion of knowledge of new and improved methods of teaching and practicing orthopaedic surgery in all its branches

- You can find out more about the Journal at http://www.jbjs.org.uk

Journal of Bone and Joint Surgery, British Volume

Link  http://www.medicalnewstoday.com/articles/114601.php

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11, 2008

As the incidence of metal-on-metal hip resurfacing has increased in recent years, especially in younger patients, research published in the Journal of Bone and Joint Surgery - British Volume (JBJS-Br) discusses occurrences of "pseudotumours" as a result.

The researchers estimate that approximately 1% of patients who have metal-on-metal hip resurfacings develop pseudotumours within five years of treatment. A pseudotumour is 'a soft-tissue mass associated with the implant…neither malignant nor infective in nature', but that causes pain and discomfort to the patient.

Most worryingly for patients and doctors is that the causes of the tumours are unknown. The research discusses possible causes including 'toxic reaction to an excess of particulate metal wear debris.' The article stresses the need for further research to be done into the incidence of pseudotumours in patients who have had this treatment.

The paper concludes that the incidence of pseudotumours must be related to metal-on-metal hip resurfacing highlighting 'the need for regular clinical follow-up for new devices'. Such follow-up would follow NICE recommendations, but the current NHS climate makes this difficult, if not impossible, to achieve.

Read the research abstract

Notes

- The Journal of Bone and Joint Surgery - British Volume is a world leading orthopaedics journal with an Impact Factor of 1.868

- JBJS-Br publishes twelve issues a year of high-quality, peer-reviewed research, overseen by an international editorial board led by Editor James Scott

- The Journal was first published in 1948 by The British Editorial Society of Bone and Joint Surgery, a registered charity (No. 209299), with the object of the advancement and improvement of education in orthopaedic surgery and allied branches of surgery and the diffusion of knowledge of new and improved methods of teaching and practicing orthopaedic surgery in all its branches

- You can find out more about the Journal at http://www.jbjs.org.uk

Journal of Bone and Joint Surgery, British Volume

AAOS SAN FRANCISCO, March 7, 2008 - Some of the purported advantages of hip resurfacing over standard arthroplasty, though not all, seem to be real, researchers found in a randomized trial.

But other pluses in activity and function can probably be chalked up to patient selection bias and expectations, reported Martin Lavigne, M.D., of the University of Montreal, and colleagues, at the American Academy of Orthopaedic Surgeons meeting here.

In the randomized trial, patients who had hip resurfacing were significantly more likely to return to work and sports and had better step and hop test scores than standard arthroplasty patients did.

But functional scores and range of motion were no better than with hip replacement, the investigators found.

Hip resurfacing gained popularity with patients and some orthopedic surgeons on the basis of assumptions about better clinical function and ability to return to a high level of activity.

While retrospective cohort studies reinforced this perceived benefit, Dr. Lavigne said, "obviously there was a bias in the patient selection for hip resurfacing." Patients who sought hip resurfacing tended to be younger, more active, healthier, and expected a more active life after surgery, he said.

The newer procedure is still controversial among orthopedic surgeons despite rapid increases, commented Tom Schmalzried, M.D., of the Orthopaedic Hospital in Los Angeles, in a press conference where there was debate over the two approaches.

"The results of good, modern total hip replacement are really, really good," he said. "So for resurfacing to have a favorable risk-to-benefit ratio, you have to show you are getting something you don't get with total hip replacement."

For a more objective answer to this issue, Dr. Lavigne's group randomized 210 patients who were candidates for either procedure to undergo either uncemented 28-mm metal-on-metal total hip arthroplasty or hybrid metal-on-metal hip resurfacing.

All procedures were done by the same three surgeons with a posterior approach. Patients were informed which surgery they underwent only afterward.

Patients had a mean age around 50. Body mass index was higher in the total hip arthroplasty group.

Functional scores were slightly worse in the hip replacement group at six months (17 versus 11 on the WOMAC scale) but identical by two years (5 for both).

At six months after surgery, hopping on the affected leg was significantly easier for resurfacing group patients ("easy" or "very easy" 91.7% versus 78.9% and "difficult" or "impossible" 8.3% versus 21.1%, P=0.023).

Likewise, climbing stairs in a step test was easier at six months in the resurfacing group compared with the replacement group ("easy" or "very easy" 94.4% versus 76.3% and "difficult" or "impossible" 5.6% versus 23.7%, P=0.015).

Hip resurfacing group patients were also more likely to return to their prior work (96% versus 83%, P=0.02).

The young age of the patients made this an important outcome, Dr. Lavigne said.

Among the patients, 152 had data on activity level pre- and post-procedure.

Despite similar activity levels before surgery (P=0.22), more hip resurfacing than hip replacement patients returned to sports activities by one year after surgery (15% versus 7% high impact and 38% versus 28% moderate impact activity, P=0.022).

On a scale that included activities of daily living as well as sports, the difference tended to favor hip resurfacing but was not significant at one year (P=0.074).

"Both groups returned to a high level of activity," Dr. Lavigne said. "Hip resurfacing patients seem to be more active, but not as much as expected."

Type of surgery had no significant impact on what factors patients reported as limiting their return to sports activities, including implant protection, discomfort, fear of instability, and thigh pain.

Hip range of motion -- including total arc, arc of rotation, flexion-extension arc, and abduction-adduction arc -- was also similar for both groups among the 122 patients with data on this outcome (P>0.05).

Satisfaction with the procedure was uniformly high over time and across treatments.

While resurfacing is a more aggressive technique, Dr. Lavigne said, the rate of complications was similar between groups.

Long-term follow-up will be important to determine whether there are differences in need for revision between the procedures, he concluded.

Dr. Lavigne reported receiving research or institutional support from Zimmer, Stryker Howmedica, Biomet, DePuy, and Smith & Nephew and consulting for Zimmer.

Dr. Schmalzried reported receiving research or institutional support from Stryker, DePuy, Johnson & Johnson, Corin, and Wright Medical Technology; receiving miscellaneous funding from Stryker, DePuy, Johnson & Johnson, Corin, Wright Medical Technology, Zimmer, and Smith & Nephew; receiving royalties from Stryker, DePuy, Johnson & Johnson, Corin, and Wright Medical Technology; holding stock options in Stryker, DePuy, Johnson & Johnson, Corin, Wright Medical Technology, Zimmer, Biomet, Bristol-Myers Squib, and Pfizer; and being a consultant for Stryker.

Primary source: American Academy of Orthopaedic Surgeons meeting
Source reference:
Lavigne M, et al "Range of motion after hip resurfacing and THA: A single-blind randomized clinical study" AAOS meeting 2008; Abstract 058.

Additional source: American Academy of Orthopaedic Surgeons meeting
Source reference:
Lavigne M, et al "A randomized study comparing surface replacement arthroplasty to total hip arthroplasty" AAOS meeting 2008; Abstract 056.

Additional source: American Academy of Orthopaedic Surgeons meeting
Source reference:
Lavigne M, et al "Return to sports after hip resurfacing and total hip arthroplasty: A randomized clinical trial" AAOS meeting 2008; Abstract 053.

Hip, knee implant makers agree to pay $311M settlement

Link  http://blog.nj.com/ledgerupdates/2007/09/hip_knee_implant_makers_to_pay.html

Posted by John P. Martin and Jeff Whelan  September 27, 2007

The nation's largest manufacturers of hip and knee implants today agreed to pay $311 million to settle allegations that they bribed top surgeons to recommend their products.

Agents gathered evidence that orthopedic surgeons routinely accepted lavish vacations, gifts and annual "consulting fees" as high as $200,000 from medical device makers in return for endorsing their implants or using them in operations.

The 30-month investigation, headed by federal prosecutors in New Jersey, marks one of the larger settlements of its kind and follows a wave of cases to spotlight questionable ethics within the health care industry.

"With these agreements in place, we expect doctors to make decisions based on what is the best interest of their patients - not the best interest of their bank account," U.S. Attorney Christopher Christie said in a statement.

The agreements covered five firms, including DePuy Orthopaedics, a subsidiary of New Jersey-based Johnson and Johnson. Together, the companies control more than 90 percent of the U.S. market in reconstructive implants, a billion-dollar field expected to surge in coming years.

Three of the manufacturers -- DePuy, Zimmer Holdings and Biomet, Inc. -- are based in Warsaw, Ind. The others are Stryker Corp., of Kalamazoo, Mich. and Smith and Nephew PLC, of London.

The civil settlements ranged from $169 million for Zimmer to $26.9 million for Biomet, based in part on the market share of each defendant, authorities said. Stryker will not pay any money.

In criminal complaints filed in federal district court in Newark, the companies admitted paying surgeons consulting fees that violated the federal Medicare Fraud Statute. The law prohibits companies from offering inducements to doctors who participate in Medicare. About two-thirds of the 700,000 knee and hip replacement surgeries performed each year are covered by Medicare.

As part of the agreement, each will also pay for a federal monitor to supervise their practices for 18 months. The monitors include former U.S. Attorney General John Ashcroft and the former U.S. Attorneys for New York and Los Angeles.
 

Dr. De Smet

Vicky Marlow, Patient Advocate/Technical Contributor, asks "What is your opinion on cementless devices for resurfacing?"


Maybe they are good, but we do not know yet. Cement is a shock absorber between prosthesis and bone or between prosthesis/ bone+cement/ bone, so maybe a good thing, certainly taking in account that Chrome Cobalt has not the same elasticity as bone and is quite stiff!

So

1. we have to wait and see

2. certainly not all patients would be good to do uncemented

3. history has shown that cemented resurfacing works very well.

Greetz   KOEN

---

Read More Doctors Opinions About Cementless Hip Resurfacing Here

March 2008

SAN FRANCISCO -  A study indicates that having a metal-on-metal bearing surface and performing high-impact activities preoperatively may be positive predictors for participating in high-impact sports after total hip arthroplasty.

To determine which patients would participate in high-impact sports activity following total hip arthroplasty (THA) and to examine the factors linked to participation in these sports, David R. Marker, BS, and colleagues submitted pre- and postoperative questionnaires to 303 THA patients who had a mean follow-up of 3 years.

The investigators found that 30% of patients participated in at least one or more high-impact sport postoperatively for an average of 4.3 hours per week.

A regression analysis revealed that a preoperative high activity level and metal-on-metal bearing surface were the only statistically significant factors to predict participation in high-impact sports postoperatively. Moreover, while a comparison of patients participating in high- and low-impact sports revealed similar preoperative Harris Hip Scores, the investigators discovered that the high-impact sport participating patients had higher postop Harris Hip Scores.

"There are many patients participating in these high-impact sports, up to 30% in our cohort," Marker said during his presentation at the American Academy of Orthopaedic Surgeons 75th Annual Meeting, held here. "The preoperative participation, as well as the metal bearing surface, were found to be predictive of postoperative participation. We found [in] the short-term follow-up that the high-impact sports patients had similar and better outcomes."

For more information:

Marker DR, Seyler TM, Ulrich SD, et al. High-impact sports after THA: Is the bearing type and independent predictor of activity level? Paper #16. Presented at the American Academy of Orthopaedic Surgeons 75th Annual Meeting. March 5-9, 2008. San Francisco.

April 2008

Using potent anticoagulants such as low-molecular-weight heparin to prevent pulmonary embolism in total hip or knee arthroplasty patients, as recommended by the Chest Physicians Consensus Statement, may actually increase the risk of all-cause mortality compared to multimodal prophylaxis measures, according to a systematic literature review published in Clinical Orthopaedics and Related Research.

"We believe the American College of Chest Physicians should reconsider their guidelines to reflect the fact that PE (pulmonary embolism) occurs despite the use of potent anticoagulants and may, in fact, expose patients to increased mortality after surgery," the authors said in the study.

Nigel E. Sharrock, BMedSci, MB, ChB, and colleagues at the Hospital for Special Surgery, New York, conducted the systematic review, which included 20 English language studies published during the last 9 years. The researchers focused on studies that involved patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA) and divided publications into three categories based on the venous thromboembolism prophylaxis regimen.

Specifically, Group A included the use of low-molecular-weight heparin, ximelagatran, fondaparinux or rivaroxaban, Group B included the use of a multimodal prophylaxis, and Group C included the use of warfarin.

"Multimodal prophylaxis (Group B) was defined as a protocol consisting of intention to use regional anesthesia (epidural or spinal) with or without intraoperative heparin during surgery or pneumatic compression and aspirin after surgery," the study authors noted.

The researchers found that the lowest number of deaths occurred among patients in Group B. Patients in Groups A and C were more than two times as likely to die compared to those in Group B, with no significant difference between Group A and Group C.

Patients in Group A also had a 60% to 70% higher risk of nonfatal PE compared to patients in Group B.

Nonfatal PE occurred in 94 of 15,839 patients in Group A (0.6%) vs. 25 of 7,193 patients in Group B (0.35%), according to the study.

"We show clinical PE occurs despite the use of powerful anticoagulants. The rate of 0.6% is comparable to the rate of 1% previously described with warfarin and low-molecular-weight heparin in cohort studies.

"This literature cannot support the use of powerful anticoagulants to prevent PE, although they clearly reduce the risk of venographically evident deep vein thrombosis," the study authors wrote.

For more information:

Sharrock NE, Gonzalez Della Valle A, Go G, et al. Potent anticoagulants are associated with a higher all-cause mortality rate after hip and knee arthroplasty. Clin Orthop Relat Res. 2008;466:714-721.

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

March 11, 2008

Both total hip replacement or total hip arthroplasty (THA), and hip resurfacing procedures continue to spark a lively ongoing discussion among orthopedic surgeons. Some are calling hip resurfacing a more effective alternative, while others are saying complications associated with resurfacing far outweigh its effectiveness.

Total hip replacement involves an orthopedic surgeon removing the head (or ball) and neck of the femur (thigh bone) and replacing them with a metal implant. The resurfacing procedure reshapes the head of the thigh bone and covers it sparing part of the bone with a metal and plastic implant.

"Hip resurfacing is not new to orthopedics it has been around for more than 10 years now," said William Maloney, MD, professor of surgery and chair of the Department of Orthopedic Surgery at Stanford, University. "We are now starting to acquire experience and measurable data associated with the procedure and its outcomes. One reason for this discussion is because orthopedic surgeons are dealing with more direct to consumer advertising today when it comes to resurfacing. Patients are coming into our offices and asking for the procedure without really understanding what is involved or even if they are a suitable candidate."

Those who perform hip resurfacing procedures say:

•It is a less invasive surgery with a shorter hospital stay and recovery time

•Patients experience a better range of motion after surgery

•Patients experience a longer implant life

Those who perform total hip replacement say:

•It is no more invasive than resurfacing

•Healing time is much the same as for resurfacing patients

•More of the patient population stands to benefit from total hip replacement

Maloney moderated a frank and fact filled discussion on the merits of both procedures at a media briefing entitled: "Getting Hip to Hip Surgery: Resurfacing and Replacement," last week at the 75th Annual Meeting of the American Academy of Orthopedic Surgeons (AAOS).

The panel of presenters included: Paul Beaule, MD, Robert Trousdale, MD, Paul Lachiewicz, MD, and Tom Schmalzried, MD.