Thank you. So why are RAMP lesions important? So RAMP lesions firstly are defined as posterior meniscus capsular lesions of the medial meniscus. We think they're important because there's a large number of biomechanical studies which demonstrate that they're associated with significantly increased anteroposterior and rotational knee laxity that is not restored by isolated ACL reconstruction. We also know that these lesions are biomechanically associated with increased ACL strain. If you repair them, you can restore normal kinematics if you do an ACL reconstruction at the same time, and as a result of that, you can reduce the strain in the ACL. The problem with RAMP lesions is that they're hard to diagnose. There's no specific physical examination test. The early MRI studies had even lower sensitivity than those that are included in this table, but you can see that even recent studies, as recent as 2017, that was only 48%. Diagnosis through arthroscopy also has its challenges. In this study from Sonnery-Cote published in 2014, when they performed a standard anterior viewing, they identified 60% of all medial meniscal tears. When they did a posterior medial compartment evaluation, they identified an extra 23%, and then when they needled that lesion, or that region rather, with a needle, they found an additional 17% of tears. The video demonstrates posterior medial compartment viewing. There's a subtle abnormality there that we've probed with a needle, and we think there's a RAMP lesion, and you can see that when you address that with a shaver, that tissue really opens up very easily, and that wouldn't happen if the meniscus was normal. That's a type 3 lesion. Image A shows a standard view of the medial compartment from anterior portal viewing. When we do a posterior medial compartment viewing, we put our scope exactly where that probe is, between the medial femoral condyle and the PCL, and D is what you see when you put your scope in there, and that's a fairly obvious RAMP lesion, different to the last one we saw in the video. So the objectives of this study were to evaluate the incidence of RAMP lesions in a large series of patients undergoing a systematic posterior medial compartment evaluation at the time of ACL reconstruction to determine the risk factors and the secondary meniscectomy rate. The methods, well, this is a retrospective analysis of all patients in the SONTI study group database who underwent primary or revision ACL reconstruction between 2012 and 2018. Exclusion criteria were major concomitant procedures and other types of meniscal lesions including root tears, horizontal tears, radial tears, vertical tears, more centrally located than the red-white zone. How we repair the lesions is with a suture hook 25 degrees through the posterior medial portal, a number zero PDS, and usually between one and three passes or one in three sutures to fix the repair. We had 3,214 patients overall in the study group, 769, or 24%, had RAMP lesions that were repaired. We only had 416 patients with a minimum of two-year follow-up, and the secondary meniscectomy rate analysis was restricted to those patients only. You can see in our multivariate analysis that we identified several important risk factors, so male gender, age less than 30, increase in chronicity of injury, whether it's a revision ACL, high degrees of pre-op laxity in terms of AP translation, and whether they had a lateral meniscal lesion were all important risk factors. In the literature, it's been suggested that spontaneous healing can occur, but we identified a 21% rate of lesions in acute knees and 26% in chronic knees, and what we also found was that at every single time point there, from three months onwards to two years, there was a statistically significant increase in the incidence of these lesions, which suggests that probably spontaneous healing doesn't account for a lot of these cases. In our secondary meniscectomy analysis, the overall rate was 10.8%, but just as we mentioned in my previous talk, if you do an ALL reconstruction, it confers a protective effect on medial meniscal repairs, and we found that that rate was 6.6% compared to in the isolated group of 14.8%, so it's a T-fold reduction, which is statistically significant. So previous studies have reported a range of ramp lesions between 9 and 30%, but this study has a significantly larger population than those previous studies, so we believe it gives a much more reliable estimate of the true incidence. There's also methodological differences, so many of the previous studies haven't probed the meniscus with a needle, but reassuringly there are other studies that have reported a very similar rate to us. For example, Kim et al. published in Arthroscopy last year, but the difference in their methodology was that they used a 70 degree scope, but they found a very similar incidence. Although the overall secondary meniscectomy rates after ACL reconstruction vary between approximately 5 and 40%, ours is the first study to our knowledge that specifically reports rates following ramp repair. So in conclusion, ramp lesions are common and occur in almost one in four ACL injured knees. A knowledge of the epidemiology and important risk factors allows an appropriate index of suspicion to be held, but despite that, we consider post-remedial compartment evaluation a mandatory part of arthroscopic evaluation in all ACL injured knees. The final point is that anterolateral ligament reconstruction at the time of ACL reconstruction confers a protective effect on medial meniscal repairs, including ramp lesions. Thank you.

RAMP lesions

knee laxity

ACL strain

diagnosis challenges

incidence and risk factors