Anterior cruciate ligament
reconstruction with remnant preservation: a prospective, randomized controlled

Hong L, Li X,
Zhang H, Liu X, Zhang J, Wei Shen J, and Feng H. Am J Sports Med.

Recent claims
suggest that a surgical procedure, which uses the remnant of the ruptured
anterior cruciate ligament (ACL), would be beneficial to the long-term outcome
of patients with an ACL rupture. Therefore, Hong and colleagues completed a
randomized controlled trial to compare the short-term clinical outcome of remnant-preservingACL reconstruction (ACLR) to the standard ACLR. Patients were included if (a) there was a complete ACL injury, (b) the tibial insertion of the ACL remnant was intact, and (c) arthroscopy confirmed that the remaining ACL length and diameter were adequate to perform the remnant-preserving procedure. Patients were excluded if (a) a bilateral knee injury was sustained; (b) there was a concurrent posterior cruciate ligament injury, posterolateral corner
injury, or grade III medial collateral ligament injury; (c) total meniscectomy,
and (d) history of knee surgery. From 525 consecutive patients, the authors
excluded 435 patients. The remaining patients were randomly assigned to either
the remnant-preserving ACLR group (45 patients) or the standard ACLR group (45
patients). Both groups underwent testing (Lachman test, pivot-shift test, and
KT-1000 arthrometer) under anesthesia, as well as a single-bundle ACLR
technique with 4-strand allografts. Patients in the remnant-preserving group
had the allograft sutured to the remnant of the native ACL (moredetailed description available in Ahn JH et al 2009). Following surgery,
all patients followed the same rehabilitation protocol and were reevaluated
using Lysholm and International Knee Documentation Committee grading systems at 3, 6, 9, 12, 18, and 24
month post-surgery. Clinical evaluations were completed preoperatively and at
least 2 years post-surgery. The authors used a Biodex detector to assess knee
proprioception (specifically, passive angle reproduction test with a target angle of 15 degrees). Final analysis
showed that ACLR with remnant-preservation was not superior to ACLR without
remnant-preservation with respect to all variables. While there were no
differences in clinical scores, physical examination, or proprioception the
ACLR with remnant-preservation required a longer tourniquet time (~90 minutes vs
~75 minutes) compared to the standard ACLR.

Overall, this
study provides some interesting data indicating that ACLR with
remnant-preservation is not superior to a single-bundle ACLR without remnant preservation. While this data can be applied clinically, one must be
careful when attempting to identify a “gold standard” of ACLR.  In this study both groups underwent a single-bundle
ACLR procedure but research has suggested that the double-bundle ACLR technique
is superior to the single-bundle procedure in terms of patient’s outcome.
Therefore, it would be beneficial to compare the remnant-preserving technique to
a double-bundle technique to truly assess patient outcomes. Further, one should
be cautious when evaluating the applicability to a certain population. In this
study over 80% of initially considered patients were not eligible. The sample
they included should represent an optimal population for the procedure but they
still found no differences between groups. It should also be noted that the
remnant -preserving technique has not been studied with regards to early onset
osteoarthritis. While the data should be interpreted cautiously, the
applicability of the study is admirable. These findings, despite the
limitations noted above, suggest that the overall outcomes are not affected by
the status of the ACL remnant; therefore, clinicians can consider this in terms
of return to play in the short-term. If a patient is considering finishing a
season with an ACL deficient knee then clinicians can rest assured that the
remnant of the injured ACL is of no concern to the overall outcome following
surgery. Tell us what you think. Have you had patients who have undergone this
ACLR with remnant preservation? If so, what was your experience with the

Written by:
Kyle Harris

Hong L, Li X, Zhang H, Liu X, Zhang J, Shen JW, & Feng H (2012). Anterior cruciate ligament reconstruction with remnant preservation: a prospective, randomized controlled study. The American Journal of Sports Medicine, 40 (12), 2747-55 PMID: 23075805