Minimally Invasive Surgery (MIS)

The concept of MIS is one of the true revolutions in surgical technique in recent times. It is applied to most surgical specialties including orthopedic surgery. At OA we strive to achieve excellence in surgery and to offer cutting edge techniques. This is balanced by a commitment to patient safety and scientifically proven advances. Our surgeons describe below how they incorporate MIS technology into surgical care at Orthopedic Associates of Portland.

Minimally Invasive Hip Surgery

The surgeons of the Maine Joint Replacement Institute of OA have taken a leadership role both nationally and in the state of Maine to investigate, understand, and offer minimally invasive hip surgery. Dr. McGrory recently chaired a task force for the AAHKS (American Association of Hip and Knee Surgeons) that produced two position statements regarding MIS surgery of the hip and knee. These statements are intended for patients and surgeons, and outline the salient issues of this type of surgery. Dr. McGrory presented these statements to other orthopedic surgeons in Maine at the annual fall meeting of the Maine Society of Orthopedic Surgeons, on September 9, 2004 at the Colony Resort in Kennebunk.

• AAHKS MIS Position Statement (patients) (146 KB)
• AAHKS MIS Advisory Statement (surgeons) (156 KB)
• AAHKS Release Notice about MIS (100 KB)

Arthroscopic hip surgery is performed more commonly at OA than any practice in the state of Maine. This type of surgery has very specific indications, and patient selection is of utmost importance. During the procedure the hip joint is distracted, and arthroscopic tools are placed in the joint (figure 1). Arthroscopic images of a chronic radial labral tear (figure 2a and b), and a traumatic radial tear (figure 3a and b) are demonstrated below. In figure 3b the tear had been debrided. Figure 4a and b show a degenerative labral tear and subsequent debridement.

Minimally invasive hip replacement surgery is offered at OA, and ongoing clinical research in this area will allow understanding of potential benefits and risks.

Dr. Brian McGrory has trained at the Zimmer Institute to perform 2 incision MIS hip surgery. After cadaver surgery at both the Zimmer Institute and the University of New England gross anatomy laboratory, Dr. McGrory performed the first 2-incision total hip replacement in Maine in August 2003. This type of surgery is currently being critically evaluated with a follow-up study of patients through Zimmer, Inc., and Dr. McGrory is participating in the national project. Dr. George Babikian has also recently trained for the 2-incision technique and plans to offer this surgery in the future.

Contemporary hip surgery continues to evolve, and currently there is a continuum with MIS surgery. In a recent study evaluating the role of MIS surgery in his practice, Dr. McGrory evaluated the height, weight, sex, and surgical incision length of 115 consecutive total hip replacement patients. The medial hospital length of stay was 3 days, and the average skin incision length measured at the completion of surgery was 13 cm (5.1 inches) with a range of 9 cm (3.5 inches) to 20 cm (7.8 inches). Skin incision length was significantly related to a patient's body mass index, with more obese patients requiring larger incisions (figure 5 [incisiongraph.doc]). Overall, patients were very pleased with the cosmetic result of the surgical scar, and there were no complications of component malposition, infection, blood clot, or failure of the hip replacement at early follow-up.