Rodilla/Knee: Si el menisco se lesiona, se resentirá el cartílago

Quantitative MRI T2 Relaxation Time Evaluation of Knee Cartilage: Comparison of Meniscus-Intact and -Injured Knees After Anterior Cruciate Ligament Reconstruction.
Li H, Chen S, Tao H, Chen S
Am J Sports Med. 2015 Jan 14. pii: 0363546514564151. [Epub ahead of print]


Abstract

BACKGROUND:
Associated meniscal injury is well recognized at anterior cruciate ligament (ACL) reconstruction, and it is a known risk factor for osteoarthritis.

PURPOSE:
To evaluate and characterize the postoperative appearance of articular cartilage after different meniscal treatment in ACL-reconstructed knees using T2 relaxation time evaluation on MRI.

STUDY DESIGN: Cohort study; Level of evidence, 3

METHODS:
A total of 62 consecutive patients who under ACL reconstruction were recruited in this study, including 23 patients undergoing partial meniscectomy (MS group), 21 patients undergoing meniscal repair (MR group), and 18 patients with intact menisci (MI group) at time of surgery. Clinical evaluation, including subjective functional scores and physical examination, was performed on the same day as the MRI examination and at follow-up times ranging from 2 to 4.2 years. The MRI multiecho sagittal images were segmented to determine the T2 relaxation time value of each meniscus and articular cartilage plate. Differences in each measurement were compared among groups.

RESULTS:
No patient had joint-line tenderness or reported pain or clicking on McMurray test or instability. There were also no statistically significant differences in functional scores or medial or lateral meniscus T2 values among the 3 groups (P > .05 for both). There was a significantly higher articular cartilage T2 value in the medial femorotibial articular cartilage for the MS group (P < .01) and the MR group (P < .05) compared with that of the MI group, while there was no significant difference in articular cartilage T2 value between the MS and MR groups (P > .05) in each articular cartilage plate. The medial tibial articular cartilage T2 value had a significant positive correlation with medial meniscus T2 value (r = 0.287; P = .024)

CONCLUSION:
This study demonstrates that knees with meniscectomy or meniscal repair had articular cartilage degeneration at 2 to 4 years postoperatively, with higher articular cartilage T2 relaxation time values compared with the knees with an intact meniscus.

Tobillo/Ankle/Knöchel/Cheville: Microfracturas por artroscopia en jóvenes con lesiones pequeñas

Functional and MRI Outcomes After Arthroscopic Microfracture for Treatment of Osteochondral Lesions of the Distal Tibial Plafond
Keir A. Ross, Charles P. Hannon, Timothy W. Deyer, Niall A. Smyth, MaCalus Hogan, Huong T. Do,  John G. Kennedy,
J Bone Joint Surg Am, 2014 Oct 15;96(20):1708-1715.

Abstract

Background: Osteochondral lesions of the distal tibial plafond are uncommon compared with talar lesions. The objective of this study was to assess functional and magnetic resonance imaging (MRI) outcomes following microfracture for tibial osteochondral lesions.

Methods: Thirty-one tibial osteochondral lesions in thirty-one ankles underwent arthroscopic microfracture. The Foot and Ankle Outcome Score (FAOS) and Short Form-12 (SF-12) general health questionnaire were used to obtain patient-reported functional outcome scores preoperatively and postoperatively. MRI scans were assessed postoperatively with use of the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score for twenty-three ankles.

Results: The average age was thirty-seven years (range, fifteen to sixty-eight years), and the average lesion area was 38 mm2 (range, 7.1 to 113 mm2). Twelve ankles had a kissing lesion on the opposing surface of the talus, and two ankles had a concomitant osteochondral lesion elsewhere on the talus. FAOS and SF-12 scores were significantly improved (p < 0.01) at the time of follow-up, at an average of forty-four months. The average postoperative MOCART score was 69.4 (range, 10 to 95), with a lower score in the ankles with kissing lesions (62.8) than in the ankles with an isolated lesion (73.6). Increasing age negatively impacted improvement in SF-12 (p < 0.01) and MOCART (p = 0.04) scores. Increasing lesion area was negatively correlated with MOCART scores (p = 0.04) but was not associated with FAOS or SF-12 scores. Lesion location and the presence of kissing lesions showed no association with functional or MRI outcomes.

Conclusions: Arthroscopic microfracture provided functional improvements, but the optimal treatment strategy for tibial osteochondral lesions remains unclear. The repair tissue assessed on MRI was inferior to normal hyaline cartilage. The MRI outcomes appeared to deteriorate with increasing lesion area, and both functional and MRI outcomes appeared to deteriorate with increasing age.

Level of Evidence: Therapeutic Level IV

General: El nuevo paradigma de la preartrosis

Osteoarthritis: From Palliation to Prevention: AOA Critical Issues.

Chu CR, Millis MB, Olson SA.

J Bone Joint Surg Am. 2014 Aug 6;96(15):e130. [Epub ahead of print]

Abstract

Osteoarthritis is a leading cause of disability. The traditional focus on late-stage osteoarthritis has not yielded effective disease-modifying treatments. Consequently, current clinical care focuses on palliation until joint replacement is indicated. A symposium format was used to examine emerging strategies that support the transformation of the clinical approach to osteoarthritis from palliation to prevention. Central to this discussion are concepts for diagnosis and treatment of pre-osteoarthritis, meaning joint conditions that increase the risk of accelerated development of osteoarthritis. The presentation of translational and clinical research on three common orthopaedic conditions-anterior cruciate ligament tear, intra-articular fracture, and hip dysplasia-were used to illustrate these ideas. New information regarding the use of novel quantitative magnetic resonance imaging (MRI) in the form of ultrashort echo time enhanced T2* (UTE-T2*) mapping to evaluate the potential for articular cartilage to heal subsurface damage in a mechanically sound environment was presented. These data indicate that improved diagnostics can both identify cartilage at risk and evaluate the effectiveness of early treatment strategies. With use of a new mouse model for intra-articular fracture, it was shown that inflammation correlated to fracture severity and that super-healer mice avoided early posttraumatic osteoarthritis in part through an enhanced ability to dampen inflammation. These findings suggest that there is a role for acute and sustained anti-inflammatory treatment in the prevention of osteoarthritis. For long-term treatment, contemporary gene-therapy approaches may offer an effective means for sustained intra-articular delivery of anti-inflammatory and other bioactive agents to restore joint homeostasis. To illustrate the potential of early treatment to prevent or delay the onset of disabling osteoarthritis, the positive clinical effects on articular cartilage and in long-term clinical follow-up after operative correction of structural abnormalities about the hip highlight the role for targeting mechanical factors in delaying the onset of osteoarthritis. Given that orthopaedic surgeons treat the full spectrum of joint problems, ranging from joint trauma to pre-osteoarthritic conditions and end-stage osteoarthritis, an awareness of the paradigm shift toward the prevention of osteoarthritis is critical to the promotion of improved clinical care and participation in clinical research involving new treatment strategies.

Rodilla/Knee/Knie: Cuidado al interpretar la RMN ante el fracaso de una ligamentoplastia

A Radiographic Assessment of Failed Anterior Cruciate Ligament Reconstruction: Can Magnetic Resonance Imaging Predict Graft Integrity?

Waltz RA, Solomon DJ, Provencher MT

Am J Sports Med 2014 May 12

Abstract

BACKGROUND: Magnetic resonance imaging (MRI) showing an "intact" anterior cruciate ligament (ACL) graft may not correlate well with examination findings. Reasons for an ACL graft dysfunction may be from malpositioned tunnels, deficiency of secondary stabilizers, repeat injuries, or a combination of factors. 

PURPOSE: To evaluate the concordance/discordance of an ACL graft assessment between an arthroscopic evaluation, physical examination, and MRI and secondarily to evaluate the contributing variables to discordance. 

STUDY DESIGN: Case series; Level of evidence, 4.

METHODS: A total of 50 ACL revisions in 48 patients were retrospectively reviewed. The ACL graft status was recorded separately based on Lachman and pivot-shift test data, arthroscopic findings from operative reports, and MRI evaluation and was categorized into 3 groups: intact, partial tear, or complete tear. Two independent evaluators reviewed all of the preoperative radiographs and MRI scans, and interrater and intrarater reliability were evaluated. Concordance and discordance between a physical examination, arthroscopic evaluation, and MRI evaluation of the ACL graft were calculated. Graft position and type, mechanical axis, collateral ligament injuries, chondral and meniscal injuries, and mechanism of injury were evaluated as possible contributing factors using univariate and multivariate analyses. Sensitivity and specificity of MRI to detect a torn ACL graft and meniscal and chondral injuries on arthroscopic evaluation were calculated. 

RESULTS: The interobserver and intraobserver reliability for the MRI evaluation of the ACL graft were moderate, with combined κ values of .41 and .49, respectively. The femoral tunnel position was vertical in 88% and anterior in 46%. On MRI, the ACL graft was read as intact in 24%; however, no graft was intact on arthroscopic evaluation or physical examination. The greatest discordance was between the physical examination and MRI, with a rate of 52%. An insidious-onset mechanism of injury was significantly associated with discordance between MRI and arthroscopic evaluation of the ACL (P = .0003) and specifically with an intact ACL graft on MRI (P = .0014). The sensitivity and specificity of MRI to detect an ACL graft tear were 60% and 87%, respectively. 

CONCLUSION: Caution should be used when evaluating a failed ACL graft with MRI, especially in the absence of an acute mechanism of injury, as it may be unreliable and inconsistent.