While a first time kneecap dislocation can usually be treated non-surgically, recurring dislocations often necessitate surgical intervention. MPFL (medial patellofemoral ligament) reconstructions have become a common surgical option and have seen improved outcomes and a high rate of return to sport.
However, it was previously unknown if this procedure is effective for people with trochlear dysplasia. Those who have recurrent patellofemoral -- or kneecap -- instability have a high incidence of trochlear dysplasia, the most common bony problem.
A new study from Hospital for Special Surgery (HSS), shared at this year's annual meeting of the American Academy of Orthopaedic Surgeons (AAOS) on March 16, seeks to determine if isolated MPFL reconstructions work for patients with trochlear dysplasia, sparing these patients larger more complicated bony procedures. It was a retrospective review of 105 patients who underwent MPFL reconstructions with Beth E. Shubin Stein, MD, sports medicine surgeon at HSS, with a 10 year follow up.
The study found high patient outcomes scores (87.2 on the Kujala Anterior Knee Pain Scale) and a high return to sports at one year (89 percent of those who participated in sports preoperatively). There was a 97 percent success rate; only 3 patients reported a postoperative dislocation.
"As surgeons, we like to do the least invasive surgery possible to fully fix the problem," said Dr. Shubin Stein, lead investigator. "With this study, we found that MPFL reconstruction is a safe and effective treatment for patients with patellofemoral instability even if in patients that have trochlear dysplasia."
In addition to MPFL reconstructions (a soft tissue procedure), surgeons can also perform a tibial tubercle osteotomy or trochleaplasty (both bony procedures) to regain stability in a patellar dislocation.
Both soft tissues and bony constraints maintain patellofemoral stability together. As such, surgeons in the past were sometimes reluctant to only perform a soft tissue procedure since it doesn't address the bony pathology that may also contribute to the instability.
"Equally as important, we showed that this technique can be done in patients who might previously be advised to undergo a bony procedure such as tibial tubercle osteotomy or trochleoplasty, which can be high risk surgeries," added Dr. Shubin Stein.
Additional HSS authors include: Joseph N. Liu, MD; Irene L. Kalbian, BA; Sabrina M. Strickland, MD; and Joseph T. Nguyen, MPH.
About Hospital for Special Surgery
Hospital for Special Surgery (HSS) is the world's largest academic medical center focused on musculoskeletal health. HSS is nationally ranked No. 1 in orthopedics and No. 2 in rheumatology by U.S. News & World Report (2016-2017), and is the first hospital in New York State to receive Magnet Recognition for Excellence in Nursing Service from the American Nurses Credentialing Center four consecutive times. HSS has one of the lowest infection rates in the country. HSS is an affiliate of Weill Cornell Medical College and as such all Hospital for Special Surgery medical staff are faculty of Weill Cornell. The hospital's research division is internationally recognized as a leader in the investigation of musculoskeletal and autoimmune diseases. Hospital for Special Surgery is located in New York City and online at http://www.