Macroscopic causes behind more than half of ACL revisions
SAN DIEGO After a review of the largest cohort of revision anterior cruciate ligament surgery from a single institution currently available in the literature, investigators from the Harvard Sports Medicine Service at Massachusetts General Hospital in Boston, M.A. have found macroscopic causes for graft failure in more than half of the revisions analyzed.
It was noted, however, that inappropriate tunnel placement was also identified in most patients and also may be related to graft failure.
Amon T. Ferry, MD, presented his groups findings at the 2011 Specialty Day of the American Orthopaedic Society for Sports Medicine.
Ferry and his team identified 173 patients who underwent revision ACL reconstruction between 1999 and 2009. Twenty of these patients, it was reported in the abstract, had previous revision ACL surgery and were excluded. The team obtained data on the remaining 153 patients. According to Ferry, this cohort displayed an average time from primary to revision ACL reconstruction of 6.5 years and an average age of 32.6 years at the time of revision.
We performed revision ACL reconstruction via an endoscopic, single-incision technique, Ferry said. This technique was used in 90.8% of patients, with the graft fixation occurring through sole utilization of an interference screw method in 96.1% of patients.
According to Ferry, bone-patellar tendon-bone (BPTB) autograft was used at the time of primary ACL reconstruction 49.2% of the time, with hamstring autograft being used 23.1% of the time and allograft being used 27.7% of the time. During revision, BPTB allograft was used 79.1% of the time, BPTB autograft was used 19.6% of the time and hamstring allograft was used 1.3% of the time.
Macrotraumatic events were associated with knee instability in 59.3% of cases, Ferry said. At the time of revision surgery, 62.7% of patients displayed evidence of meniscal injury with 74.5% displaying significant chondral damage. Around 68.6% of patients displayed a completely disrupted graft, with 7.2% displaying a partially torn graft and 22.2% displaying a graft that was intact but attenuated.
Three patients had a competent graft sacrificed because of nonanatomic tunnel placement and arthrofibrosis. Patients with tibial revision and femoral revision represented 65.4% and 80.5% of the cohort, respectively, and 87.6% of these patients underwent tunnel revision.
Avoid non-anatomic tunnels
Ferry said the authors believe appropriately-placed tunnels are capable of being reused, however, non-anatomic tunnels will be encountered and must be bypassed entirely. Allograft or bone substitute can be used in tunnel widening, and although an interference screw could be used to achieve adequate fixation surgeons should be aware that additional tibial fixation could be necessary.
This study contributes to the body of literature the largest cohort for revision ACL reconstruction from a single location, Ferry concluded. We found that nonanatomic tunnels are often encountered, might be predictors of graft failure, and when found should not be reused. by Robert Press
- Ferry AT, Van de Velde S, Li G, et al. Revision anterior cruciate ligament reconstruction: A review of 153 cases. Paper #9554. Presented at the 2011 Specialty Day of the American Orthopaedic Society of Sports Medicine. Feb. 19. San Diego.
- Amon T. Ferry, MD, can be reached at Valley Orthopedics, 9250 N 3rd Street #2030, Phoenix, AZ 85020; 623-882-1292; email: firstname.lastname@example.org.
- Disclosure: The authors have no relevant financial disclosures.