METHODS: This prospective comparative study was conducted from 2009 to 2012. Patients with ACL injuries who underwent knee arthroscopy and MRI were included in the study. Two radiologists who were blinded to the clinical history and arthroscopic findings reviewed the pre-arthroscopic MR images. The presence and type of meniscal tears on MRI and arthroscopy were recorded. Arthroscopic findings were used as the reference standard. The accuracy, sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of MRI in the evaluation of meniscal tears were calculated.
RESULTS: A total of 65 patients (66 knees) were included. The sensitivity, specificity, accuracy, PPV, and NPV for the MRI diagnosis of lateral meniscal tears in our patients were 83, 97, 92, 96, and 90 %, respectively, whereas those for medial meniscus tears were 82, 92, 88, 82, and 88 %, respectively. There were five false-negative diagnoses of medial meniscus tears and four false-negative diagnoses of lateral meniscus tears. The majority of missed meniscus tears on MRI affected the peripheral posterior horns.
CONCLUSION: The sensitivity for diagnosing a meniscal tear was significantly higher when the tear involved more than one-third of the meniscus or the anterior horn. The sensitivity was significantly lower for tears located in the posterior horn and for vertically oriented tears. Therefore, special attention should be given to the peripheral posterior horns of the meniscus, which are common sites of injury that could be easily missed on MRI. The high NPVs obtained in this study suggest that MRI is a valuable tool prior to arthroscopy.
METHOD: A single, masked, controlled study was designed. This comprised two matched groups of 12 chronically ACLD patients awaiting reconstruction and a group of 12 matched uninjured control subjects. Only one ACLD group received a home-based exercise and educational programme. Assessment before and after the exercise intervention included: knee joint stability (clinical and KT1000 evaluation); muscle strength (Cybex II); standing balance and functional performance (agility, [corrected] and subjective tests).
RESULTS: At the time of initial assessment there were no statistically significant differences in any measures for the two ACLD groups but both ACLD groups were significantly different from the uninjured control group as regards quadriceps strength and function. Measures taken after six weeks showed no significant improvement in the untreated ACLD group or in the uninjured control group. The treated ACLD group showed significant improvement in the following measures: quadriceps strength measured at 60 degrees and 120 degrees per second (p < 0.001); single leg standing balance with eyes closed (p < 0.001); instrumented passive stability at 20 lb (89 N) force (p = 0.003); agility and subjective performance (p < 0.001). The incidence of unstable episodes had decreased in the treated ACLD group, reducing further damage to the joint.
CONCLUSION: This study leaves little doubt that pre-operative physiotherapy had a positive effect on motor function in ACLD subjects and should be prescribed routinely to maximize muscle stabilizing potential prior to reconstruction. Patients report improved stability and, in certain cases, may avoid surgery. The finding that exercise increased the passive stability of the joint was unexpected and requires further investigation.
METHODS: Medial femoral condyle defect was created in both knees of twenty-four mature New Zealand white rabbits, and the animals were divided into four groups containing six animals each. After 3 weeks, the right knees were transplanted with PVA-chitosan-MSC, PVA-chitosan scaffold alone, alginate-MSC construct or alginate alone. The left knee was kept as untreated control. Animals were killed at the end of 6 months after transplantation, and the cartilage repair was assessed through Brittberg morphological score, histological grading by O'Driscoll score and quantitative glycosaminoglycan analysis.
RESULTS: Morphological and histological analyses showed significant (p < 0.05) tissue repair when treated with PVA-chitosan-MSC or alginate MSC as compared to the scaffold only and untreated control. In addition, safranin O staining and the glycosaminoglycan (GAG) content were significantly higher (p < 0.05) in MSC treatment groups than in scaffold-only or untreated control group. No significant difference was observed between the PVA-chitosan-MSC- and alginate-MSC-treated groups.
CONCLUSION: PVA-chitosan hydrogel seeded with mesenchymal stem cells provides comparable treatment outcomes to that of previously established alginate-MSC construct implantation. This study supports the potential use of PVA-chitosan hydrogel seeded with MSCs for clinical use in cartilage repair such as traumatic injuries.