Six-year study shows 19% drop in success with all-inside meniscal repair

Researchers discovered an average of two failures per year with the Meniscus Arrow.

Although inside-out procedures for meniscal repair remain the gold standard, the field has recently experienced a surge in all-inside approaches. Short-term studies using the Meniscus Arrow, an all-inside device, reported comparable success rates to inside-out techniques. But new long-term research reveals that the success of the Arrow dropped from 90% to 71%.

At 6.6 years follow-up, researchers discovered eight failures in 28 patients. Patients averaged 43 months between new symptoms and additional repair. “As a result of this experience, we feel that the utilization of the arrow should be critically reassessed,” said David R. Diduch, MD, an orthopedist with the University of Virginia. “And we no longer use the Arrow.” He presented his findings at the 2005 International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine Congress.

The latest study sheds new light on Diduch and colleagues’ 2002 publication, which reported that the Meniscus Arrow (Linvatec) proved successful in 90% of concomitant ACL reconstruction patients at 2.3 years. The initial study included 32 patients. Researchers evaluated 87.5% of the original group for longer follow-up and found a 19% drop in success. “Extended follow-up reveals a substantial attrition to the success rate of meniscal repair with the Arrow.” The new research constitutes one of the first long-term studies on all-inside repairs, Diduch said.

Extended study, revised implications

A single surgeon performed the initial surgeries, which all included ACL reconstruction, using patella tendon autograft, Diduch said. The patients required an average of 2.5 arrows. An independent observer analyzed participants at follow-up using KT-2000, IKDC and VAS scales. Researchers determined failure as the need for additional meniscectomy. “A history of recurrent mechanical symptoms coupled with a positive meniscal finding on an exam constituted a clinical failure,” Diduch said.

After six years, investigators found eight failures involving the medial meniscus, he said. “Linear regression analysis revealed a failure rate of roughly two per year with a very high co-efficient of determination,” Diduch said.

Researchers determined that meniscal failure was not linked to ACL laxity, he said. “The KT-2000 evaluation did not demonstrate a statistically significant difference in the knees with successful meniscus repair and the knees in which the repair failed,” he said. “In fact, the knees in which the repair failed had a slightly tighter KT value than the other group.”

The Arrow was introduced in 1996. In just three years, surgeons used the device in 34% of all meniscal repairs, Diduch said. The research findings provide cautionary evidence to the widespread use of the Arrow. “Although we did not attempt to directly compare the Arrow to inside-out suture, the long-term success rate of 71% is inferior to the inside-out literature standard of roughly 90%,” he said. Diduch also said that many other reports about the Arrow noted complications, “mostly related to it being a rigid device.”

For more information:
Diduch DR, Lee GP, Hart J. Outcomes after meniscal repair using the Meniscal Arrow in knees undergoing concurrent anterior cruciate ligament reconstruction: analysis of durability of repair. #97. Presented at the 2005 International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine Congress. April 3-7, 2005. Hollywood, Fla.