Background:
A spectrum of anterolateral rotatory laxity exists in anterior cruciate ligament (ACL)–injured knees. Understanding of the factors contributing to a high-grade pivot shift continues to be ...refined.
Purpose:
To investigate factors associated with a high-grade preoperative pivot shift and to evaluate the relationship between this condition and baseline patient-reported outcome measures (PROMs).
Study Design:
Cross-sectional study; Level of evidence, 3.
Methods:
A post hoc analysis was performed of 618 patients with ACL deficiency deemed high risk for reinjury. A binary logistic regression model was developed, with high-grade pivot shift as the dependent variable. Age, sex, Beighton score, chronicity of the ACL injury, posterior third medial or lateral meniscal injury, and tibial slope were selected as independent variables. The importance of knee hyperextension as a component of the Beighton score was assessed using receiver operator characteristic curves. Baseline PROMs were compared between patients with and without a high-grade pivot.
Results:
Six factors were associated with a high-grade pivot shift: Beighton score (each additional point; odds ratio OR, 1.17; 95% CI, 1.06-1.30; P = .002), male sex (OR, 2.30; 95% CI, 1.28-4.13; P = .005), presence of a posterior third medial (OR, 2.55; 95% CI, 1.11-5.84; P = .03) or lateral (OR, 1.76; 95% CI, 1.01-3.08; P = .048) meniscal injury, tibial slope >9° (OR, 2.35; 95% CI, 1.09-5.07; P = .03), and chronicity >6 months (OR, 1.70; 95% CI, 1.00-2.88; P = .049). The presence of knee hyperextension improved the diagnostic utility of the Beighton score as a predictor of a high-grade pivot shift. Tibial slope <9° was associated with only a high-grade pivot in the presence of a posterior third medial meniscal injury. Patients with a high-grade pivot shift had higher baseline 4-Item Pain Intensity Measure scores than did those without a high-grade pivot shift (mean ± SD, 11 ± 13 vs 8 ± 14; P = .04); however, there was no difference between groups in baseline International Knee Documentation Committee, ACL Quality of Life, Knee injury and Osteoarthritis Outcome Score, or Knee injury and Osteoarthritis Outcome Score subscale scores.
Conclusion:
Ligamentous laxity, male sex, posterior third medial or lateral meniscal injury, increased posterior tibial slope, and chronicity were associated with a high-grade pivot shift in this population deemed high risk for repeat ACL injury. The effect of tibial slope may be accentuated by the presence of meniscal injury, supporting the need for meniscal preservation. Baseline PROMs were similar between patients with and without a high-grade pivot shift.
Objectives:
The combination of anterior cruciate ligament (ACL) reconstruction plus lateral extra-articular tenodesis (LET) has shown promising results during preclinical biomechanical and clinical ...testing at reducing anterolateral rotatory laxity; however, no studies have examined its effectiveness during a dynamic functional task. Therefore, we used the drop vertical jump (DVJ) to compare in vivo biomechanics of ACL reconstructed patients with and without LET from a subset of patients within the Stability randomized clinical study. We hypothesized that there would be a difference in peak knee abduction moment (KAM) between the two treatment groups at six months following surgery.
Methods:
This is a subset of patients taken from one center, within a pragmatic, multicenter prospective randomized clinical trial. Thirty patients were randomized to receive ACL reconstruction alone (n=16) or ACL reconstruction plus LET (n=14). At six months postoperative, all patients performed a drop vertical jump test and knee kinetics and kinematics were measured using three-dimensional motion analysis. Biomechanical variables of interest included peak initial contact and stance values for knee abduction moment and angle, knee flexion moment and angle and knee internal rotation moment and angle. Independent groups t-tests were used to assess kinetic and kinematic differences between the injured limbs of both treatment groups.
Results:
There was no significant difference in peak KAM between those who received ACL reconstruction alone (1.31 %BW×ht) and those who received an ACL reconstruction plus LET (1.14 %BW×ht) (Mean Difference, 0.17; 95% CI, -0.50 to 0.84, p = 0.60). Similarly, there were no differences in peak knee flexion moment or peak knee internal rotation moment between treatment groups (p=0.59 and p=0.37 respectively). There were also no significant differences in knee abduction angle, knee flexion angle or knee internal rotation angle at initial contact (p=0.40, p=0.08, p=0.23 respectively) or peak stance phase (p=0.10, p=0.44, p=0.19 respectively).
Conclusion:
We found no significant biomechanical differences between treatment groups at six months postoperative. However, these are the preliminary results of a larger continuing study and, at this time, no definitive conclusions can be made.
Toll-like receptor-4 (TLR4) has been implicated in the pathogenesis of different renal diseases in rodent models. However, in human kidney disease, TLR4 expression and regulation is not well ...understood. We hypothesized that renal TLR4 expression plays a role in chronic kidney disease (CKD) and is associated with proteinuria, kidney function, histological diagnosis, and inflammatory mediators.
We quantified TLR4 mRNA as well as expression of macrophage chemoattractant protein-1 (MCP-1), transforming growth factor-β₁ (TGF-β₁) and interleukin-6 (IL-6) in human kidney biopsies from 70 patients with CKD. We measured kidney function, urinary MCP-1 protein excretion, and the amount of chronic damage. Macrophage load was quantified by CD68 and vascularization by CD34 immunostaining.
TLR4 expression correlated significantly with MCP-1 and TGF-β₁ expression. High TLR4 expression was associated with high IL-6 expression. TLR4 expression was significantly upregulated in patients with severe proteinuria, and in patients with chronic ischemic renal damage and IgA nephropathy, when compared to patients with thin glomerular basement membrane disease. TLR4 expression did not correlate with creatinine clearance, renal outcome, macrophage load or chronic damage.
We show for the first time that renal TLR4 expression was significantly associated with the pro-inflammatory marker MCP-1 and the profibrotic molecule TGF-β₁ in kidney biopsies from patients with CKD, suggesting that increased expression of TLR4 is an important feature of CKD.