Increased rates of obesity in Europe lead to difficulties in delivering orthopaedic care

The rates of obesity have tripled in European countries since the 1980s and this trend poses as one of the greatest public health challenges for the 21st century, according to the World Health Organization Regional Office for Europe.

Based on WHO statistics, 2% to 8% of health costs and 10% to 13% of deaths in different parts of the European region are attributable to obesity.

In the United Kingdom, a study published in 2007, “The Foresight Report,” predicted about half of all U.K. citizens could be considered obese by 2050 if the current trends continue, at a cost of about £50 billion per year.

A high body mass index (BMI) can make certain surgeries much more difficult, Steven R. Bollen, MB, FRCS, FRCSEd Orth, FFSEM, told Orthopaedics Today Europe. For an ACL reconstruction procedure and other ligament reconstruction surgeries, obesity can certainly lead to a higher rate of revision or failure of the procedure, Bollen said.

“There has only been one published paper on the subject. The study showed that if you have a BMI over 30, then the failure rate for an ACL reconstruction surgery is about 35%. We did some work, which we presented a couple of years ago, that shows if you reach a weight of 100 kilos, just the forces you put through the joints and ligaments through daily living can exceed the strength of the fixation for the surgically reconstructed ligaments,” he said.

Treating an obese patient is entirely different – and more difficult – than treating a patient of less weight, spine surgeon Marek Szpalski, MD, PhD, told Orthopaedics Today Europe, agreeing with Bollen’s assessment.

“The first thing, with obese patients, imaging before surgery has some problems. In obese patients, for example, it is much more difficult to get quality preoperative imaging. Having a precise diagnosis is more difficult because you do not have the same quality of imaging as in non-obese patients,” Szpalski said. “Also, obese patients tend to have more medical problems, cardiac problems, metabolic problems, breathing problems, which makes all of the preoperative steps more difficult. It is also more difficult for the anesthesiologist. Having to negotiate the anesthesia for an obese patient is much more difficult, and can prove problematic if it is a real emergency.”

Images: Hintermann B

Obesity may affect anesthesia

Once an obese patient is under anesthesia, surgeons must face the challenge of positioning them in an appropriate way, Szpalski said. Surgeons always try to avoid putting pressure on the abdominal area to reduce bleeding, he said, and that is much more difficult to do in the obese patient. Even modern spine-specific operating tables are not made to accommodate the abdomen of a highly obese patient, he said.

There is increased bleeding during surgery among these patients because of the positioning problem and simply because they have more tissue to cut through, Szpalski said.

Some instruments can even be too short to use in a patient who is very obese, he said.

“You might even have problems with the length of the instrument during a procedure,” according to Szpalski.

Once you get to the spine, however, the procedure itself is typically not any different, but the time of surgery tends to be longer, he noted.

Outcomes not always worse

Although the overall surgical procedure can certainly be more difficult for an obese patient, Beat Hintermann, MD, told Orthopaedics Today Europe, the outcomes in this patient population may not necessarily be worse than those of a patient who is not obese.

A retrospective chart study by Hintermann and colleagues published in Foot and Ankle International in 2011 looked at 118 obese patients with a BMI of 30 or above who underwent total ankle replacement (TAR) between May 2000 and June 2008.

Hintermann said the survivorship of the prosthesis components was comparable to the results obtained in non-obese patients. Most of the literature claims that the outcomes for an obese patient after this type of procedure would be negative, but our study could not back up this claim, he said.

“From that point of view, we were just not able to confirm that,” Hintermann said.

Avoid ankle fusion, replacement

While results of the TAR procedure are typically the same for obese patients and patients with a BMI less than 30, Hintermann said it is not ideal to operate on an obese patient for an ankle replacement or ankle fusion.

Obese patients have a high rate of “flat feet,” which is basically a breakdown of the foot, according to Hintermann, and because of that he has had to refuse treatment or to perform foot and ankle procedures on an obese patient due to the high likelihood of failure or revision.

“Basically, when you implant a prosthesis it works only if the foot itself is stable. If the foot is collapsed or broken down, it affects the prosthesis greatly,” he said.

More comorbidities, more complications

Obese patients also tend to have more preoperative comorbidities and other maladies that may make the procedure much more difficult to complete. An obese patient’s comorbidities tend to be more difficult to address in a procedure than a non-obese patient’s comorbidities, Hintermann said.

Bollen agreed with Hintermann’s assessment and said he would refuse to perform an ACL reconstruction surgery in a patient with a very high BMI.

“I would not do it. If you want to have anything stabilized, they have to lose weight before the surgery. BMI is a difficult thing. If you look at most of the rugby players, their BMI puts them into the obesity category, because muscle is heavier than fat,” Bollen said. “They have the muscle control to control the weight, but if you have just fat rather than muscle, that is just a weight that puts abnormal forces on your joints and ligaments. It is more difficult for an obese patient. They are carrying all that weight around. Fortunately, you do not see too many obese patients who tear their ligaments, since they do not do too many sports or exercises that have the violent twisting or cutting movements that lead to the injuries.”

While some procedures are typically the same when carried out in obese patients, Anne Lübbeke, MD, DSc, told Orthopaedics Today Europe that during total joint reconstruction procedures, obese patients have more revisions.

“The problem we see here mainly is an increase in early revisions, especially after total hip replacements (THRs),” she said. “Early revisions are generally due to infection or dislocation, and some due to a technically more challenging intervention. These revisions are more prevalent in patients with a BMI over 35.”

In patients who undergo total knee replacement (TKR), a BMI more than 35 also tends to result in increased rates of infection and revision. Lübbeke said obesity leads to a more difficult THR and TKR surgical procedure for the patient and surgeon alike.

“Regarding surgical difficulties in THR, visualization and implant positioning can be more difficult, which partly explains the higher dislocation rate,” Lübbeke said. Moreover, instruments may sometimes not be adapted. It is not well known yet which technique performs best in very obese patients, she said.

Soft tissue handling may be another problem, according to Lübbeke. “Injuries to the soft tissues can lead to more infections. Wound closure in multiple layers is recommended in obese patients.”

Also, pre-surgery antibiotic dosage may be insufficient in patients with a BMI more than 35 and dosage adjustment may help to decrease infection rates, she said, but this needs to be verified in future studies.

However, Lübbeke stressed that patient satisfaction, pain relief and functional improvement are substantial in obese patients, and most studies have reported similar results to those obtained in non-obese patients.

Losing weight is key

Despite this evidence, Lübbeke stressed it is important for a surgeon or physician to urge an obese patient to lose weight before the procedure.

“Preoperatively, weight loss should be recommended, and encouraging the patient to maintain some form of exercise, so they do not lose so much muscle mass before surgery is key,” she said. “Even a weight loss of 5% to 10% of body weight, together with exercise, has been shown to be effective in reducing pain and functional disability.”

Bollen agreed with Lübbeke. He said an ACL or ligament reconstruction procedure for an obese patient can lead to more complications for the patient. The procedure itself, he said, is also more difficult to perform when a patient is obese.

Just getting to the damaged ligament is much more difficult with an obese patient, he said, since cutting through several inches of fat is a much more complicated process.

“They have bigger problems with wound healing, as well,” Bollen said. “Technically, the procedure is also more difficult because you have to go through several inches of fat to get to knee. Of course you have problems with anesthesia for an obese patient. Quite often they are diabetic, as well.”

Losing weight preoperatively is key for obese patients if they wish to have a successful surgery, he said, and weight loss can make the rehabilitation process a lot easier.

However, obese patients have fewer options when it comes to rehabilitation, Bollen said, as certain exercises can be dangerous for someone who has a reconstructed ligament.

“I am all for people who are overweight doing more exercise and getting their weight under control, but they have to be careful what they do. Jumping around on a netball court when you are 17 or 18 stone increases your risk of injury. Swimming, bicycling, rowing — they are all great for obese patients because they do not put much stress on the joints or ligaments,” he said. – by Robert Linnehan

• References:
• Barg A. Foot Ankle Int. 2011;doi:10.3113/FAI.2011.0925.
• Hage, WK, Bollen SR. Can ACL reconstruction be justified in the obese? Presented at the British Orthopaedic Association and the Irish Orthopaedic Association Combined Meeting. Sept. 13-16, 2011. Dublin.
• Messier SP. JAMA. 2013;doi:10.1001/jama.2013.277669.
• State of the nation’s waistline. Obesity in the UK: Analysis and expectations. http://www.nationalobesityforum.org.uk/media/PDFs/StateOfTheNationsWaistlineObesityintheUKAnalysisandExpectations.pdf. Published January 2014. Accessed Oct. 22, 2014.
• World Health Organization. Regional Office for Europe. Obesity. http://www.euro.who.int/en/health-topics/noncommunicable-diseases/obesity/obesity. Accessed Oct. 22, 2014.

• For more information:
• Steven R. Bollen, MB, FRCS, FRCSEd Orth, FFSEM, can be reached at The Yorkshire Clinic, Bradford Road, Bingley, West Yorkshire, United Kingdom, BD16 1TW; email: kath.kenny@ramsayhealth.co.uk.
• Beat Hintermann, MD, can be reached at the Clinic for Orthopaedics and Traumatology at Kantonsspital Baselland, Rheinstrasse 26, 4410 Liestal, Switzerland; email: beat.hintermann@ksbl.ch.
• Anne Lübbeke, MD, DSc, can be reached at the Division of Orthopaedics and Trauma Surgery, Geneva University Hospitals, 4, rue Gabrielle-Perret-Gentil, 1211 Geneva, Switzerland; email: Anne.LubbekeWolff@hcuge.ch.
• Marek Szpalski, MD, PhD, can be reached at the Department of Orthopedic and Trauma Surgery at IRIS South Teaching Hospitals, Rue Dejoncker 46 1060, Brussels, Belgium; email: mszp@skynet.be.

Disclosures: Hintermann receives royalties for the HINTEGRA ankle prosthesis from Integra ILS. Szpalski is a consultant for Integra, Nanovis and LFC. Bollen and Lübbeke have no relevant financial disclosures.

Should patients with a BMI at a certain level only be operated on at specific centers by experienced surgeons?

Many factors should be considered

This question cannot be answered with a definite “yes” or a definite “no”. First of all you should define the level of body mass index of concern. For example, in a patient with a slightly increased body mass index (BMI) of between 25 and 30 kg/m², foot and ankle surgery can be performed without any definite risk. Patients with a BMI of more than 30 are definitely at higher risk for preoperative, intra-operative or postoperative complications.

Here, also, the surgeries should be separated. There are definitely different types of surgeries. There is an easy surgery, such as ankle arthroscopy, and in this patient group I do believe obese patients can also be operated on at a usual foot and ankle center without any specialist.

However, for complex surgery, which includes a realignment surgery, ankle fusion or ankle replacement, those patients definitely belong in a special center or in the hands of a surgeon who has a certain degree of experience.

If I have a patient of a normal weight and I say they are allowed to perform partial weight bearing for 6 weeks postoperatively, it can happen that the patient makes a wrong step and places full weight-bearing on the operated foot. Usually nothing should happen. However, in obese patients that means twice the normal weight and it means that the fixation should be absolutely perfect in order to withstand such forces. You cannot do the perfect fixation, you cannot do the perfect reposition, if you do not have a high degree of experience with such complex surgeries.

Another point that applies to the complex surgeries is if you correct the deformity or implant a foot and ankle replacement joint, sometimes it is possible to over or under correct the deformity. In the case of foot and ankle replacement, you may not achieve the absolute perfect alignment of the prosthesis components. I strongly believe such slight mistakes are absolutely harmless in patients with a normal weight, but may be clinically significant in patients with obesity because of the different forces placed across the joint and across the prosthesis once the patients start to walk.

Alexej Barg, MD, is at the Clinic of Orthopaedic Surgery, Kantonsspital, in Liestal, Switzerland.
Disclosure: Barg has no relevant financial disclosures.

Prior weight loss is key

A number of factors influence outcome following elective joint arthroplasty, including patient factors such as gender and medical comorbidity, technical factors such as positioning of the prosthesis, and provider factors such as hospital and surgeon procedure volumes.

There is a relationship between increasing body mass index (BMI) and worsening outcome following elective joint arthroplasty. Studies have shown when potential confounding factors such as surgeon volume are taken into account, increasing BMI is independently predictive of worse outcomes for operating time, thromboembolism, blood loss, postoperative infection, dislocation and patient reported measures. We should, therefore, expect poorer outcomes across the board in obese patients, even when they are operated on at specific centers by experienced surgeons.

The present evidence suggests the results of elective joint arthroplasty in patients with a BMI between 30 kg/m² and 40 kg/m² are probably comparable with the results of the procedure in non-obese patients. Morbidly obese patients may expect improvement in pain and function following elective joint arthroplasty, although the overall results are inferior when compared with non-obese patients. Regardless of surgeon experience, patients with a BMI greater than 40 kg/m² should be advised to lose weight prior to surgery or be counselled regarding the inferior results before proceeding with surgery. Bariatric surgery may have a role in patients with morbid obesity refractory to conventional lifestyle adaption measures. There is evidence bariatric surgery can reduce joint pain and functional limitation and may also lower the risks of complications following any subsequent arthroplasty procedures.

Ewan Goudie, StR, Trauma and Orthopaedic Surgery, is at Victoria Hospital, in Kirkcaldy, United Kingdom.
Disclosure: Goudie has no relevant financial disclosures.