For the past few years, robotic assistance in orthopedic surgery has become increasingly popular. National advertisement campaigns showing patients after robotic-assisted joint replacements recovering more quickly and gaining better function are filling internet searches for total hip and knee replacements. The real question is, does it matter? Does robotic assistance in hip and knee replacement really make a difference? Should you as a patient or family member seek out surgeons using this technology?

What is Robotic Surgery for Joint Replacement? 

Robotic surgery performed with the now common robotic arm, the MAKO by Stryker, had the first surgery performed in 2006. Since that time, marked advancement in the technology and application has been experienced. In 2013, MAKO was officially acquired by Stryker and the system now allows for total and partial knee replacements in addition to hip replacements. It utilizes a CT-guided plan to help guide component placement during the operation. It allows for next-generation levels of preparation and execution during surgery, ideally improving outcomes and recovery.

Similarly, in 2016, Smith & Nephew acquired the Navio, a handheld robotic system for partial and total knee replacement from Blue Belt Technologies. This imageless system utilizes advanced techniques for anatomic mapping and balancing to help execute a very precise plan during surgery. It provides direct feedback and guidance during surgery to help limit error.

Both of these technologies are completely surgeon controlled, but add another dimension of precision to a procedure. They provide constant feedback on location, similar to how a GPS system works in a car. The difference is that if the surgeon deviates from the plan without preparing to do so, the robotic controls will stop the deviation and help limit the risk of human error. 

Robotic Surgery for Hip/Knee Replacement Matter?

The reason for the robotic revolution in orthopedics is precision. Many patients and surgeons ask if robotic assistance is necessary or if it actually helps patients. Those who are proponents of robotics site the use of technology while driving. Now that we have GPS and phones to give directions, would you ever go back to using a paper map? Sure, you could definitely get from point to point B, and if you’ve driven the route thousands of times you would be comfortable, but if the plan changes or anatomy is slightly different than expected, would you be ready? If there was a better or more efficient route to be ready or anticipate issues, why wouldn’t you use it?

Literature repeatedly shows that the most experienced surgeons in the world have an error rate of >3% from acceptable during knee replacement, and the error rate is even higher in hip replacement when using conventional instruments. With robotic technology, that deviation from ideal/planned is <1%. With robotic technology, the window of error is 1mm! 

Patients and surgeons often ask if that matters. The most simple and honest answer right now is that we are not entirely sure. Research has shown that there are trends towards better outcomes, lower long-term costs, and greater implant longevity. Truthfully, the technology has not been around long enough to say that hips and knee will last forever because of the robotic technologies, but what we can say with complete confidence is that implants are placed with more precision because of them. If we can make the perfect and individualized plan for each patient, and execute it precisely, than there can be no better attempt at nearing the perfect, reproducible joint replacement.

The real key to success is the right patient, for the right surgery, with the right surgeon. If all of these metrics are met, and there is a tool that your “right” surgeon is using to be even better and more accurate, than the real question should be, why you would want it done any other way! 

Since 2017, Dr. Werger has been performing all varieties of hip and knee replacement with robotic assistance. He is one of the most experienced robotic surgeons in New England, and continues to work on optimizing the technology for every patient. 

Contact our office today to meet Dr. Werger and see if you are a good candidate for hip or knee replacement. 

In 2003, the American Dental Association (ADA) and the American Academy of Orthopaedic Surgeons (AAOS) first published guidelines regarding antibiotic use for dental procedures following hip and knee replacement. These recommendations have been addressed twice by this joint panel since that time, with the latest publication in 2012 suggesting that the data is not strongly for or against antibiotics before dental work. Ultimately, the decision to use antibiotics for dental procedures should be made with consideration of each patient’s health and surgery.

When do we recommend antibiotics?

Most dental procedures do not require antibiotics, but because you have an artificial joint, we often recommend extra precaution to limit the risk of mouth bacteria seeding the joint through the bloodstream.

You should take preventive antibiotics before dental procedures if:

• You have an inflammatory type of arthritis such as rheumatoid arthritis or lupus
• Your immune system has been weakened by disease, drugs or radiation.
• You had a joint replacement less than 2 years ago
• You’ve had previous infections in your artificial joint
• You are undernourished or malnourished
• You have hemophilia
• You have cancer or are in remission

For procedures that have a higher risk of gum bleeding, we also advise antibiotic prophylaxis:

• Dental extractions
• Periodontal (gum disease) procedures
• Placement of dental implants
• Endodontic (root canal) surgery
• Initial placement of orthodontic bands (not brackets)
• Regular cleaning of teeth or implants where significant bleeding is anticipated

Antibiotics for Dental Procedures

• If you are NOT allergic to Penicillin, 2 grams of Amoxicillin or Cephalexin taken one hour prior to the procedure.
• If you ARE allergic to Penicillin, 600mg of Clindamycin taken orally prior to the procedure.

We are here to answer all of your questions and to address any of your hip/knee needs. Contact Dr. Werger for a consultation today!

Watters, W III, Rethman, MP, Hanson, NB, et al:  AAOS-ADA Clinical Practice Guideline Summary: Prevention of Orthopaedic Implant Infection in Patients Undergoing Dental Procedures. Journal of the American Academy of Orthopedic Surgeons. March 2013; 21:180-189.; doi:10.5435/JAAOS-21-03-180

Joint Replacement is a relatively major surgery. Not long ago, patients spent 1-3 days in the hospital following the procedure to work with physical therapy and monitor for issues with pain. The hospital setting has been very successful, so why change something that works?

Patient Experience

The hospital is a busy, and sometimes, chaotic environment, and the many moving parts are not always directed towards your care. In the ambulatory setting, there is considerably more surgeon control over the care episode. The teams are smaller and highly specialized, translating to an efficient and more personalized experience. Most centers that perform outpatient total joint procedures are highly specialized for orthopedic care.

For you, outpatient joint replacement will likely be a less stressful surgical experience….and this means a quicker recovery.

But What about the Risks?

Not all patients are appropriate candidates for outpatient surgery. Despite this, the projections from 2015 estimated that 50% of total hip and knee replacements would be performed in outpatient facilities by 2027. This is directly related to improved pain control options, less invasive surgical techniques, and more diligent management of risk factors known to complicate surgery.

The key to success for the patient is appropriate consideration and preparation by your surgical team. A thorough history and exam will be supplemented by the standard preoperative work-up including: EKG, a complete metabolic panel, complete blood count, and HgbA1c in diabetics.

Preparation is Key

Unlike hospital-based surgery, a lot of the work when performing same-day procedures is front-loaded, utilizing a multi-disciplinary team before the surgery. This means that you will have a well-defined plan for your post-surgery care before you even have the procedure.

You should select a family member or close friend to stay with you for the first 72 hours after you go home. Ideally, this person will attend your preoperative evaluations to better understand the plan after surgery.

Dr. Werger’s team includes an Arthroplasty Navigator to streamline the process. You will be contacted by our navigator after scheduling your surgery. This will be a friendly and consistent contact, who with your surgeon, will help manage perioperative expectations, coordinate logistics on the day of surgery, and plan for home care.

Home Health Care will often be coordinated to visit you at home. Their team will visit regularly and includes nurses and physical therapists to make your first week at home more comfortable.

Metal sensitivity(or metal hypersensitivity) is an allergic reaction triggered by the body’s immune system. Unlike the clear and immediate reaction one might experience to pollen and dust, allergies to metal present in a more delayed fashion. Basically, your body develops a negative memory regarding a specific antigen (i.e. metal) and overreacts when that metal shows up again. It’s not usually an immediate response like a bee sting, but rather, it can take several days or more before the signs begin to appear.

When a patient has a reported allergy to an orthopedic implant, it is usually a reaction to nickel, cobalt, or chromium. The incidence of sensitivity to nickel (usually seen as a skin reaction to cheap jewelry) is 10-15%, but to date, there is not a consensus between this type of reaction and issues with orthopedic implants containing nickel.

What are the Signs of a Metal Allergy?

Common symptoms of a metal allergy condition are:

1. skin hives, eczema, redness and itching resulting from skin contact (from cheaper/costume jewelry)
2. inflammation and pain associated with a metal orthopedic or dental implant

The signs and symptoms of metal implant sensitivity are not well-defined. While there are a relatively small number of cases scattered around the internet and in clinical case reports of more profound reactions such as skin rash, blistering, significant warmth, and generalized weakness, the findings for deep orthopedic implants are often a diagnosis of exclusion.

How Can You Test for Hypersensitivity?

Patch Testing– involves the incorporation of different potential allergens onto an adhesive grid that is then left in place for 24-96 hours. The skin reaction is recorded from mild-severe. The benefit of this type of test is that its administration is common for trained dermatology and allergy clinics. The drawback is that this is a test of skin reaction to metal and does not assess the reactivity of deeper tissues. Additionally, there is varying standardization reported for this test.

Lymphocyte Transformation Test (LTT)– blood test which tests immune cell responses to different metals. Metal-LTT testing can identify which people are susceptible to metal sensitivity. Metal-LTT testing can also identify which specific metals cause sensitivity responses and which specific metals do not cause excessive immune reactions. The drawback is that this test requires a special kit and is only performed by a small number of laboratories. The benefit is a deeper and more clear assessment of hypersensitivity. See the links below to learn more and order the kit.

Orthopedic Analysis

MELISA-LTT

Are There Options for Patients with Allergies?

Studies have shown that 20-25% of people with well-performing total joint replacements have a metal hypersensitivity, and 60% of individuals with poorly performing implants have a metal hypersensitivity. While not all patients sensitive to implant-related metals will do poorly, there is a correlation between metal hypersensitivity and decreased post-operative satisfaction.

When a patient has a history of metal hypersensitivity, there may be lower risk implant options for joint replacement, and the patient should discuss these options with their surgeon. Patients with nickel allergies are often treated with implants containing mostly titanium and ceramics. Oxidized zirconium has been proposed as the lowest nickel implant option for knee replacements. Patients must understand that allergies may change the surgical options, and that not all complex procedures can be performed without the potential for using an implant that may incite a response.

Should You Be Tested?

Not every patient needs to be tested for metal allergies because the clinical incidence is relatively rare. If you have had a reaction to jewelry or other metals in the past, you should have a discussion with your surgeon about testing. I prefer the LTT for patients with a metal sensitivity history to confirm my proposed implant choices are safe. When in doubt, talk with your surgeon!

We are happy to assist you in making the best decision, and are here to answer all of your questions. Contact Dr. Werger  for a consultation and to learn which option may be best for you.

Hallab N, Merritt K, Jacobs JJ. Metal sensitivity in patients with orthopaedic implants. J Bone Joint Surg Am 2001; 83-A: 428-36

Guenther, D., Thomas, P., Kendoff, D. et al. Allergic reactions in arthroplasty: myth or serious problem? International Orthopaedics 2016;40: 239.

According to CDC data, in 2010 alone >310,000 hip replacements were performed in patients age 45 and older. Recent projections expect that number may reach almost 600,000 by 2030. We are seeing a significant increase in hip replacements for younger patients. From 2000-2010, the population with the largest volume increase was age 45-54. Additionally, by 2010, hip replacements in patients age 55-64 accounted for a higher percentage than those >75.

This translates to a younger, and often more physically-demanding, population receiving hip replacements. The components are a combination of ceramics, plastics, and metals. Increased physical demands classically translate to more rapid wear. Using a car analogy, if you drive your car harder and faster, you cannot expect your tires to last as long as they would if you never slammed on the gas or the breaks…. therefore, treat your joint right and it should last longer, right?

A common reply to the longevity question is that your hip will last 15-20 years. Most data now suggest that hip and knee replacements have an annual failure rate of 0.5-1%. This means that a joint replaced today will have a 90-95% chance of lasting 10 years and an 80-85% chance that it will last 20 years. Barring complication, we hope and expect that advances in technology and bearing surfaces will keep your new joint functioning much longer!

Research on bearing surfaces is often hard to control, and most is performed in the lab on a motion/impact simulator. It is important to recognize that claims made by industry are not entirely validated once that joint is implanted into a patient. While the components make up a large part of the longevity of your new joint, the implanted position of the components among other patient specific factors significantly influence the life of the replacement. With this in mind, the marketing claims are based on lab data and should not entirely be taken literally.

The best way to learn about options for you is to contact a trained professional. Contact Dr. Werger  today to learn more!

Kurtz S et al. Projections of primary and revision hip and knee arthroplasty in the United States from 2005 to 2030. J Bone Joint Surg Am. 2007 Apr;89(4):780-5.

Wolford ML, Palso K, Bercovitz A. Hospitalization for total hip replacement among inpatients aged 45 and over: United States, 2000–2010. NCHS data brief, no 186. Hyattsville, MD: National Center for Health Statistics. 2015.

I personally prefer the direct anterior approach for most of my primary hip replacement procedures. In certain circumstances, I will also utilize a direct lateral or posterior approach, but I plan for each and every case on an individual basis based on specific patient characteristics. There are benefits and disadvantages to every approach, and despite what marketing campaigns have proposed, no approach is infallible.

The direct anterior approach allows for a patient to be positioned on his/her back. Some surgeons require a special table to help with exposure, though I avoid this additional table to limit more moving parts and complexity in the operating room. Having a patient supine (on their back) is beneficial for anesthesia and allows me to directly compare leg lengths during surgery. It also makes using intraoperative xray to confirm desired component placement a whole lot easier and more reliable. For the patient, multiple high quality studies have proven that the anterior approach is better than posterior and lateral approaches with regards to pain and mobility in the first 6 weeks after surgery. The reality is that this published benefit is equalized by 6 weeks after surgery. With the anterior approach, there are no motion or position-related restrictions after surgery. The main complications attributed to this approach are numbness along the thigh and an increased risk of fracture of the bone during surgery. Despite the media promoting this as the solution to dislocations more commonly associated with the posterior approach (2-4%), there are a very small number of anterior hip dislocations that occur as well (<1%). Critics also cite a more difficult ability to extend the exposure during complex cases, however this approach has been used by the vast majority of European surgeons for decades for all primary and revision cases without issue. Extension is absolutely possible and extension in this position still offers the benefit of a visible assessment of leg lengths and easy xray confirmation of component position.

Posterior and lateral approaches are the workhorse approaches for most surgeons in complex cases and the majority of primary procedures in the US (>80%). They easily allow for wide exposure and can be readily extended if the case dictates a change in plan. The common critique is that the posterior approach has a higher rate of dislocation after surgery, and many patients are frustrated with the mobility restrictions during recovery. The lateral approach involves moving and reattaching muscles around the hip. It is excellent for exposure and the rate of dislocation after this approach is minimal at best. The major critique is pain, sometimes chronic, with pressure on the side of the hip which can be associated with an occasional limp. There are also immediate motion restrictions in most cases after this approach.

One additional approach, the superior approach, is also being used by select surgeons. This approach adopts a muscle-sparing variation to the posterior approach. It requires specialized instrumentation, but proposes the benefits of a very low dislocation and fracture rate. The patient is typically lying on his/her side during this procedure which makes direct assessment of leg lengths more difficult.

Patients should choose their surgeon based on their personal comfort and after weighing the risks and benefits of each option. My preferred approach is direct anterior because I believe it helps my patients more quickly become active, and I prefer to directly evaluate leg length during the surgery using cues from the hip anatomy, xray confirmation, and also direct comparison with the opposite leg.

We are happy to review your case and discuss surgical and nonsurgical options.

1. Bergin PF, Doppelt JD, Kephart CJ, Benke MT, Graeter JH, Holmes AS, Haleem-Smith H, Tuan RS, Unger AS. Comparison of minimally invasive direct anterior versus posterior total hip arthroplasty based on inflammation and muscle damage markers. J Bone Joint Surg Am. 2011; 93(15):1392-8.
2. Rodriguez JA, Cooper HJ, Robinson J. Direct anterior approach to THR: what it is and what it is not. Current Reviews in Musculoskeletal Medicine. 2013;6(4):276-278
3. Sheth D, Cafri G, Inacio MC, Paxton EW, Namba RS. Anterior and Anterolateral Approaches for THA Are Associated With Lower Dislocation Risk Without Higher Revision Risk. Clin Orthop. 2015; 473(11):3401-8.
4. Taunton, Michael J. et al. Direct Anterior Total Hip Arthroplasty Yields More Rapid Voluntary Cessation of All Walking Aids: A Prospective, Randomized Clinical Trial. J Arthroplasty. 2014; 29(9):169-72.

A 2016 Washington Post/Kaiser Family Foundation survey found that 1 in 3 patients who took opioids for at least two months reported feeling addicted or dependent on the drugs. In addition, patients taking opioids prior to surgery have greater post-surgical pain, and face a higher risk of pneumonia, over-sedation and even death. It is not uncommon to have post-surgical patients report they felt symptoms of “withdrawal” after they stopped taking their pain medications only a few weeks following surgery.

According to the U.S. Department of Health and Human Services, more people died from drug overdoses in 2014 than in any year on record, and the majority of drug overdose deaths (more than six out of ten) involved an opioid. Since 1999, the rate of overdose deaths involving opioids (including prescription pain relievers and heroin) nearly quadrupled. On an average day in the U.S., more than 650,000 opioid prescriptions are dispensed, 3,900 people initiate nonmedical use of prescription opioids, and 78 people die from an opioid-related overdose. According to the CDC, in 2015 alone, more than 22,000 people died from prescription opioid overdoses, and countless more have had their lives influenced by dependence.

How did we get here?

In 1996, the American Pain Society coined the concept of “pain as the 5^th vital sign”. This came over a decade after a letter to the New England Journal of Medicine stated that “the development of addiction is rare in medical patients with no history of addiction.” In the early 90s, narcotic prescriptions increased by 2-3 million each year, and by 1996, that figure jumped to 8 million. Purdue Pharma (maker of OxyContin) released an advertising campaign in 1998 called “I Got My Life Back.” It followed six people who suffered from chronic pain and were treated with OxyContin. In this video, they stated about OxyContin “They don’t wear out; they go on working; they do not have serious medical side effects….So, these drugs, which I repeat, are our best, strongest pain medications, should be used much more than they are for patients in pain.”

A year after this video campaign was distributed, over 11 million opioid prescriptions were distributed. In 2007, the Purdue Pharma and three of its executives were charged with misbranding OxyContin and downplaying the possibility of addiction. Three executives pleaded guilty, and the company settled with the U.S. government for $635 million.

In March 2016, CDC Director Tom Frieden wrote in the New England Journal of Medicine that data about long-term use of prescription opioids is lacking. But, he wrote, “We know of no other medication routinely used for a nonfatal condition that kills patients so frequently.” Several more studies have shown that use of opioids for chronic pain may actually worsen pain and functioning, possibly by increasing pain perception.

Where are we today?

Now nearly 2 decades since the medical push for little or no pain, we have an opioid industry that is 2^ndworldwide to cancer medications in profitability for big pharmaceutical companies. 80% of the world’s narcotics are consumed through prescriptions in the US, which represents only 5% of the world’s population [Nation In Pain]. According to IMS Health, Vicodin and non-branded hydrocodone combination painkillers are the most commonly prescribed drugs in the US.

While effective for controlling severe pain, we now recognize that opioid medications are best utilized in short duration and with a defined course. They are notthe optimal treatment for chronic pain conditions. Chronic pain from arthritis should not be managed with opioid medications, especially as patients await joint replacement to treat these conditions. Additionally, the duration of use following surgery should be limited and controlled to help avoid the known tolerance and addiction effects of these medications. Under careful supervision and with appropriate indications, these can be very effective medications for patient care.

To highlight the potential dangers of opioids, the American Academy of Orthopedic Surgeons (AAOS) created a campaign to educate providers and patients. Their message:  “Painkillers are easy to get into. Hard to escape.”

If you or a loved one is struggling with pain medications, contact your physician to discuss safe alternatives before it is too late.