The purpose of total joint arthroplasty of the hip and knee is to safely
and effectively relieve pain, restore motion, and improve function. In less
than three months, the vast majority of patients can return to the activities
of daily living and can participate in certain sports. As a result, total
joint arthroplasty has become one of the most successful and widely acclaimed
procedures of the modern era.
Recently, minimally invasive surgery, which involves a smaller incision
(defined as <10 cm) or multiple smaller incisions, has been introduced to
both hip and knee replacement
The premise is to reduce the trauma of surgery while maintaining the perceived
high levels of safety, efficacy, and durability of the procedure. If it is
done successfully, patients can expect a shorter hospital stay, quicker
recovery, faster rehabilitation, improved function, and better cosmetic
appearance, which should all translate to lower costs and higher patient
Minimally invasive surgery is not a new concept. The minimally invasive
direct coronary artery bypass surgery (MIDCAB) was pioneered by cardiac
surgeons in the early
1990s4. With use of
tiny incisions scattered around the chest, cardiac revascularization was
accomplished without the need for sternotomy and the pump. The results were
truly impressive. The length of stay was reduced by two days, and the costs
were substantially lowered. Promotional marketing of this new surgery was done
with great fanfare.
However, almost ten years after the introduction of the minimally invasive
direct coronary artery bypass procedure, only about 25% of cardiac surgeons
use this technique5.
Wound infection, myocardial infarction, atrial fibrillation, stroke, and
mortality continue to be problems. Properly done prospective, comparative
studies are lacking. The safety, efficacy, and durability of the procedure
have not been demonstrated
time, the minimally invasive direct coronary artery bypass procedure has
evolved and has now become more widely accepted with sternotomy and without
This raises a question. Will we follow the same path, or will we learn from
the cardiac experience and do the appropriate prospective controlled studies,
which will, in turn, give us the knowledge to provide the best care for our
Minimally invasive surgery for total joint arthroplasty should not be used
to benefit an individual surgeon, a manufacturing company, or a hospital.
Unfortunately, minimally invasive surgery seems to have become a marketing
tool for these groups.
To become accepted by and acceptable to the majority of orthopaedic
surgeons, minimally invasive surgery must be subjected to properly designed
and rigorously controlled studies to test its safety, efficacy, and
durability. Before minimally invasive surgery can be adopted as a standard of
care, statistical data from multiple centers must be collected, analyzed, and
subjected to peer review.
The concept of minimally invasive surgery is a good one. Technological
advances, including new surgical procedures, encourage better patient care.
Minimizing tissue trauma is desirable, but not at the expense of safety,
efficacy, durability, and overall patient satisfaction. The precision and
position of component implantation cannot be compromised. To gain widespread
acceptance, any new procedure must meet these stringent criteria.
Total joint arthroplasty has many complications; some of the more serious
ones are irreversible. The only good solution for many of these poor outcomes
is prevention through technical excellence, which may be more difficult with
minimally invasive surgery.
Although minimally invasive surgery may appeal to younger, more active
patients (those who are between thirty and sixty years old), their primary
concern should be function and durability. Moreover, minimally invasive
surgery may be contraindicated in this subgroup since many of them have
protrusio deformities, fibrous or osseous ankylosis, or a hip scarred by
previous surgery or they are obese, thereby making minimally invasive surgery
technically more difficult.
If its safety and efficacy can be established, minimally invasive surgery,
like minimally invasive direct coronary artery bypass surgery, may become the
procedure of choice for elderly or high-risk
Until we have sufficient scientific evidence to support its universality,
minimally invasive surgery should be performed only by surgeons who can
evaluate the procedure and thus compare it with the conventional technique.
Unless the safety and efficacy of the procedure are validated scientifically,
no promotional or marketing support of minimally invasive surgery should be
condoned. Otherwise, as orthopaedists, we will have failed in our duty to
provide our patients with the best possible care.