Background Anterior cruciate ligament (ACL) injury can lead to reduced function, meniscal lesions, and early joint degeneration. Preservation of a torn ACL using the Internal Brace technique might re-establish normal knee kinematics, avoid donor-site morbidity due to tendon harvesting, and potentially maintain proprioception of the knee. Methods Fifty subjects were recruited for this study between December 2015 and October 2016. Two groups of individuals who sustained a unilateral ACL rupture were included: Those who underwent surgery with preservation of the injured ACL (Internal Brace technique; IB) and those who underwent ACL reconstruction using a hamstring tendon graft (all-inside technique; AI). Subjective self-Administered scores were used: The German version of the IKDC Subjective Knee Form (International Knee Documentation Committee), the German version of the WOMAC (Western Ontario and McMaster Universities Arthritis Index), SF-36 (short form), the German version of the KOOS (Knee Osteoarthritis Outcome Score), and the German version of themodified Lysholm Score by Lysholm and Gillquist. Anterior tibial translation was assessed using the KT-1000 Arthrometer (KT-1000 Knee Ligament Arthrometer, MEDmetric Corp., San Diego, CA, USA). Magnetic resonance evaluation was performed in all cases. Results Twenty-Three subjects (46 Š%) were men, and the mean age was 34.7 years. The objective IKDC scores were normal in 15 and 14 patients, nearly normal in 11 and 7 patients, and abnormal in 1 and 2 patients, in the IB and AI groups, respectively. KT-1000 assessment showed a sideto-side difference of more than 3 Šmm on maximum manual testing in 11 (44 Š%) and 6 subjects (28.6 Š%) in the IB and AI groups, respectively. In the postoperative MRI, 20 (74 Š%) and 22 subjects (96 Š%) in the IB and AI groups had an intact ACL. Anterior tibial translation was significantly higher in the IB group compared with the AI group in the manual maximum test. Conclusions Preservation of the native ACL with the Internal Brace primary repair technique can achieve comparable results to ACL reconstruction using Hamstring autografts over a short term. Clinically relevant limitations such as a higher incidence of pathologic laxity, with patients more prone to pivot-shift phenomenon were observed during the study period.
- anterior cruciate ligament
- knee injuries