Abnormal tibiofemoral kinematics following ACL reconstruction are associated with early cartilage matrix degeneration measured by MRI T1rho

University of California San Francisco, School of Medicine, USA.
The Knee (Impact Factor: 1.94). 07/2011; 19(4):482-7. DOI: 10.1016/j.knee.2011.06.015
Source: PubMed


Altered kinematics following ACL-reconstruction may be a cause of post-traumatic osteoarthritis. T(1ρ) MRI is a technique that detects early cartilage matrix degeneration. Our study aimed to evaluate kinematics following ACL-reconstruction, cartilage health (using T(1ρ) MRI), and assess whether altered kinematics following ACL-reconstruction are associated with early cartilage degeneration.
Eleven patients (average age: 33 ± 9 years) underwent 3T MRI 18 ± 5 months following ACL-reconstruction. Images were obtained at extension and 30° flexion under simulated loading (125 N). Tibial rotation (TR) and anterior tibial translation (ATT) between flexion and extension, and T(1ρ) relaxation times of the knee cartilage were analyzed. Cartilage was divided into five compartments: medial and lateral femoral condyles (MFC/LFC), medial and lateral tibias (MT/LT), and patella. A sub-analysis of the femoral weight-bearing (wb) regions was also performed. Patients were categorized as having "abnormal" or "restored" ATT and TR, and T(1ρ) percentage increase was compared between these two groups of patients.
As a group, there were no significant differences between ACL-reconstructed and contralateral knee kinematics, however, there were individual variations. T(1ρ) relaxation times of the MFC and MFC-wb region were elevated (p ≤ 0.05) in the ACL-reconstructed knees compared to the uninjured contralateral knees. There were increases (p ≤ 0.05) in the MFC-wb, MT, patella and overall average cartilage T(1ρ) values of the "abnormal" ATT group compared to "restored" ATT group. The percentage increase in the T(1ρ) relaxation time in the MFC-wb cartilage approached significance (p=0.08) in the "abnormal" versus "restored" TR patients.
Abnormal kinematics following ACL-reconstruction appear to lead to cartilage degeneration, particularly in the medial compartment.

Download full-text


Available from: Bryan Haughom, Mar 21, 2015
  • Source
    • "Current surgical treatments for antero-posterior laxity and rotational instability of the human knee, typically via reconstruction of the anterior cruciate ligament (ACL), allow a satisfactory correction and an acceptable subjective sensation of joint stability [1]. However, secondary degenerative changes occur as in non-surgically treated ACL lesions [2], these being due to inadequate restoration of physiological knee mobility and stability [3,4]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The comprehension of human knee laxity and of the failures of relevant surgical reconstructions of the anterior cruciate ligament (ACL) can be enhanced by the knowledge of the laximetric status of the contralateral healthy knee (CHK). Rarely this is available in patients, directly from the skeletal structures, and for a number of the standard clinical tests. The general aim of this study was to measure the extent to which laxity occurs immediately before surgery in the ACL deficient knee (ADK) with respect to CHK, in a number of standard clinical evaluation tests. Thirty-two patients with ACL deficiency were analyzed at ADK and at CHK by a navigation system immediately before reconstructions. Knee laxity was assessed based on digitized anatomical references during the antero-posterior drawer, Lachman, internal-external rotation, varus-valgus, and pivot-shift tests. Antero-posterior laxity was normalized based on patient-specific length of the tibial plateau. In the drawer test, statistical significance (p < 0.05) was found for the larger antero-posterior laxity in ADK than in CHK, on average, of 54' in the medial and 47' in the lateral compartments, when measured in normalized translations. In the Lachman test, these were about 106' and 68'. The pivot-shift test revealed a significant 70' larger antero-posterior central laxity and a 32' larger rotational laxity. No statistically relevant differences were observed in the other tests. The first conclusion is that it is important to measure also the antero-posterior and rotational laxity of the uninjured contralateral knee in assessing the laxity of the injured knee. A second is that the Lachman test shows knee laxity better than the AP drawer, and that the pivot-shift test was the only one able to reveal rotational instability. The present original measurements and analyses contribute to the knowledge of knee joint mechanics, with possible relevant applications in biomedical and clinical research.
    Full-text · Article · Jun 2014 · BioMedical Engineering OnLine
  • [Show abstract] [Hide abstract]
    ABSTRACT: Studies have reported that knee kinematics and rotational laxity are not restored to native levels following traditional anterior cruciate ligament (ACL) reconstruction. This has led to the development of anatomic ACL reconstruction, which aims to restore native knee kinematics and long-term knee health by replicating normal anatomy as much as possible. The purpose of this review is to give an overview of current dynamic knee laxity measurement devices with the purpose of investigating the significance of dynamic laxity measurement of the knee. Gait analysis is not included. The subject was discussed with experts in the field in order to perform a level V review. MEDLINE was searched according to the discussions for relevant articles using multiple different search terms. All found abstracts were read and scanned for relevance to the subject. The reference lists of the relevant articles were searched for additional articles related to the subject. There are a variety of techniques reported to measure dynamic laxity of the knee. Technical development of methods is one important part toward better understanding of knee kinematics. Validation of devices has shown to be difficult due to the lack of gold standard. Different studies use various methods to examine different components of dynamic laxity, which makes comparisons between studies challenging. Several devices can be used to evaluate dynamic laxity of the knee. At the present time, the devices are continuously under development. Future implementation should include primary basic research, including validation and reliability testing, as well as part of individualized surgery and clinical follow-up. Diagnostic study, Level V.
    No preview · Article · Dec 2011 · Knee Surgery Sports Traumatology Arthroscopy
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: BACKGROUND:Cartilage repair (CR) procedures are widely accepted for treatment of isolated cartilage defects in the knee joint. However, it is not well known whether these procedures prevent degenerative joint disease. HYPOTHESIS:Cartilage repair procedures prevent accelerated qualitative and quantitative progression of meniscus degeneration in individuals with focal cartilage defects. STUDY DESIGN:Cohort study; Level of evidence, 2. METHODS:Ninety-four subjects were studied. Cartilage repair procedures were performed on 34 patients (osteochondral transplantation, n = 16; microfracture, n = 18); 34 controls were matched. An additional 13 patients received CR and anterior cruciate ligament (ACL) reconstruction (CR&ACL), and 13 patients received only ACL reconstruction. Magnetic resonance imaging at 3.0-tesla with T(1ρ) mapping and sagittal fat-saturated intermediate-weighted fast spin echo (FSE) sequences was performed to quantitatively and qualitatively analyze menisci (Whole-Organ Magnetic Resonance Imaging Score [WORMS] assessment). Patients in the CR and CR&ACL groups were examined 4 months (n = 34; n = 13), 1 year (n = 21; n = 8), and 2 years (n = 9; n = 5) after CR. Control subjects were scanned at baseline and after 1 and 2 years, ACL patients after 1 and 2 years. RESULTS:At baseline, global meniscus T(1ρ) values (mean ± SEM) were higher in individuals with CR (14.2 ± 0.5 ms; P = .004) and in individuals with CR&ACL (17.1 ± 0.9 ms; P < .001) when compared with controls (12.8 ± 0.6 ms). After 2 years, there was a statistical difference between T(1ρ) at the overlying meniscus above cartilage defects (16.4 ± 1.0 ms) and T(1ρ) of the subgroup of control knees without cartilage defects (12.1 ± 0.8 ms; P < .001) and a statistical trend to the CR group (13.3 ± 1.0 ms; P = .09). At baseline, 35% of subjects with CR showed morphological meniscus tears at the overlying meniscus; 10% of CR subjects showed an increase in the WORMS meniscus score within the first year, and none progressed in the second year. Control subjects with (without) cartilage defects showed meniscus tears in 30% (5%) at baseline; 38% (19%) increased within the first year, and 15% (10%) within the second year. CONCLUSION:This study demonstrated more severe meniscus degeneration after CR surgery compared with controls. However, progression of T(1ρ) values was not observed from 1 to 2 years after surgery. These results suggest that CR may prevent degenerative meniscus changes.
    Full-text · Article · Oct 2012 · The American Journal of Sports Medicine
Show more