Isolated Meniscus Tears in Adolescent Patients Treated with Platelet-Rich Plasma Intra-articular Injections: 3-Month Clinical Outcome.

OBJECTIVES: Meniscus repair is a challenge for a practitioner, as an injured meniscus can lead to osteoarthritic joint changes with a greatly disabling outcome. Platelet-rich plasma has been regarded as a promising therapy to help induce healing. The purpose of the study is to clinically assess the effectiveness of PRP treatment in adolescents with meniscal lesions. METHODS: This retrospective study analyzed 30 patients with meniscal tears, aged 12 to 17 years, who had documented MRI meniscal lesion and persistent knee pain. In order to evaluate the outcome, the Lysholm knee scoring scale and numerical rating scale were used before injection and 3 months after treatment. RESULTS: Patients had a mean age of 13.93 years, 70% girls and 30% boys. The most affected was the medial meniscus. The mean value before injection on the numerical rating scale (NRS) of pain was 7.73, after the treatment being of 2.0. After treatment, 76.7% of the patients had "excellent" and "good" outcomes, while before injection, just 3% of the patients had a "good" score. CONCLUSIONS: Platelet-rich plasma treatment can be effective in improving the clinical outcomes of adolescent patients with meniscus tears, for whom conservative management and physical therapy have failed to achieve pain relief.

Comparison of T2* mapping between regular echo time and ultrashort echo time with 3D cones at 3 tesla for knee meniscus.

The objectives of this study were to compare the ultrashort T2* relaxation time with the T2* relaxation time using the 3 dimensional (3D) cones sequence in 3 groups of patients with normal, degenerated, and torn knee menisci, and to demonstrate the additional effect of the ultrashort echo time (UTE) signal intensity.Following institutional review board approval, 42 knee magnetic resonance imaging (MRI) scans of 42 patients who presented with knee pain and underwent knee MRIs, with the 3D Cones of UTE sequence (minimum TEs: 32 µs) and a 3T MRI scanner (Discovery 750, GE Healthcare, Waukesha, WI), were analyzed. The enrolled patients were classified into 3 subgroups:normal meniscus on conventional MRI, with no positive meniscus-related physical examination in medical records;meniscal degeneration with signal changes on conventional MRI; andmeniscal tear.For the quantitative assessment, the mean values inside user-drawn regions of interest (ROIs) of the medial menisci were drawn on UTE T2* map and T2* map. For statistical analyses, 1-way analysis of variance (ANOVA) with post-hoc analysis using the Tukey HSD test was conducted to compare groups, and effect size was used to compare the discrimination power.The ultrashort T2* relaxation times were higher in patients with meniscal tear than in those with normal and degeneration groups (P <.05, respectively) whereas T2* relaxation times were not statistically significantly different. The ultrashort T2* relaxation times showed higher effect sizes than the T2* times between tear and normal/degeneration.The ultrashort T2* relaxation times showed better delineation of meniscal degeneration or tears than T2* relaxation times. The ultrashort T2* relaxation times could be more sensitive at differentiating between normal and pathologic meniscal conditions in patients.

Nerve growth factor inhibition with tanezumab influences weight-bearing and subsequent cartilage damage in the rat medial meniscal tear model.

OBJECTIVE: To investigate whether the effects of nerve growth factor (NGF) inhibition with tanezumab on rats with medial meniscal tear (MMT) effectively model rapidly progressive osteoarthritis (RPOA) observed in clinical trials. METHODS: Male Lewis rats underwent MMT surgery and were treated weekly with tanezumab (0.1, 1 or 10 mg/kg), isotype control or vehicle for 7, 14 or 28 days. Gait deficiency was measured to assess weight-bearing on the operated limb. Joint damage was assessed via histopathology. A second arm, delayed onset of treatment (starting 3-8 weeks after MMT surgery) was used to control for analgesia early in the disease process. A third arm, mid-tibial amputation, evaluated the dependency of the model on weight-bearing. RESULTS: Gait deficiency in untreated rats was present 3-7 days after MMT surgery, with a return to normal weight-bearing by days 14-28. Prophylactic treatment with tanezumab prevented gait deficiency and resulted in more severe cartilage damage. When onset of treatment with tanezumab was delayed to 3-8 weeks after MMT surgery, there was no increase in cartilage damage. Mid-tibial amputation completely prevented cartilage damage in untreated MMT rats. CONCLUSIONS: These data suggest that analgesia due to NGF inhibition during the acute injury phase is responsible for increased voluntary weight-bearing and subsequent cartilage damage in the rat MMT model. This model failed to replicate the hypotrophic bone response observed in tanezumab-treated patients with RPOA.