decision making and treatment of partial ulnar collateral ligament tears. These are my disclosures. Certainly ulnar collateral ligament injuries are a very lucrative and concerning issue for not only Major League Baseball but also amateur athletes. So how do we diagnose partial thickness tears, the degree from full thickness to partial? Thickness tears are more likely to require surgical treatment. Does location of partial tear predict treatment? And we have an athlete with a partial tear, now what? So obviously this is a major, major problem. So we are all very familiar with the clinical symptoms of partial ulnar collateral ligament tears, medial elbow pain during the late cocking and early acceleration phase. Athletes may describe loss of velocity or control. They may have pain with minimal gapping of valgus stress and maybe even have pain with dynamic valgus stress test. These are examples of the dynamic valgus stress test. This is just another technique to perform a dynamic moving valgus stress test. So several studies have been published looking at outcomes in professional athletes. This is a study out of the Colorado Rockies organization with 43 UCL injuries from one organization over a five-year period. Thirty-five players had incomplete injuries, 24 were pitchers, 28 players with non-operative treatment had both returned to play and returned to the same level of play and not returned to a lower level. Ten of these position players returned to the same level at 90 percent, 18 pitchers returned to the same level of 94 percent. So players with incomplete UCL injuries who completed non-operative rehabilitation had an 84 percent overall success rate of return to play. This is a study out of the Cleveland Clinic that looked at reliability of MRI-based classification. They looked at six-stage MRI over nine fellowship-trained specialists from multiple institutions, found a very high agreement among those that are fellowship-trained. They essentially graded Type 1 as proximal injuries, Type 2 as mid-substance injuries and Type 3 as distal injuries. Grade A were partial and B were complete in these classifications. Again another study out of the Cleveland Clinic looking at predictors of failure and non-operative management of ulnar-collateral ligament injuries. This is in 32 pitchers with a mean age of 22. Partial treatment was non-operative for all UCL injuries. Eleven of the 32 failed and required UCL reconstruction. Twenty-one or 66 percent were successfully returned to the same level of play for one year without surgical intervention. Of this group, nine of the 11 that failed non-operative treatment were distal tears and 17 of the 21 who did not fail were proximal tears. High-grade tears and distal location, 88 percent or 7 out of the 8 failed. So this is indicative of more proximal injuries were more likely to be able to be treated non-operatively. Again another study out of the Cleveland Clinic looking at the prognostic utility of the MRI-based classification. They looked at 80 patients, 29 patients completed non-operative management, 59 percent of the tears were treated non-operatively, 100 percent of the partial proximal tears were successfully treated non-operatively, however 97 percent of the distal tears were treated operatively. So complete and distal tears had an increased risk of failing non-operative treatment compared with proximal and partial tears. Again this is looking at the same group out of the Cleveland Clinic, 40 baseball players, 16 MRI with partial tears and essentially found that if you had a proximal tear you were much more likely to be successful whereas the mid-substance and distal tears were much more likely to fail. We performed a stress ultrasound evaluation of medial elbow instability in a cadaveric model in 2014 with 12 cadaveric elbows. We released the anterior band of the anterior bundle and that resulted of 2 millimeters of ulnar humeral gapping whereas release of the posterior band of the anterior bundle resulted in a gapping of 1.4 millimeters. When you release the entire anterior bundle this caused a gapping of nearly 3.5 millimeters. A study out of the Cleveland Clinic looked at biomechanical analysis in 16 cadaveric specimens. They created intact partial and distal tears. The posterior distal insertion of the ulnar collateral ligament contributed most to rotational stability and stiffness of the medial elbow when subjected to vagus stress both at 90 and 120 degrees. At higher flexion angles the posterior insertion contributed more to stability. Anterior insertions had a greater stability at the lower flexion angles so 30 and 60 degrees which is the area that we see most of our injuries in our throwers. Looking at distal blood supply, Luteal Farrow published this study in 2011. Chris Camp also published another study looking at the proximal portion contributed to more vascularity as opposed to distally and Brandon Erickson also confirmed this with load disbursement studies looking at the load more focal on the distal side than the proximal side. So size does matter in treatment of partial tears. Location matters. Type of participation matters. So how do we treat these? Active rest for how long? Somewhere between four and six weeks typically. For more chronic treatment we can talk about PRP and mesenchymal stem cells. We want to certainly look at the core and the kinetic chain looking at the elbow, the shoulder and the lower extremity. You want to have a return to throwing program that's appropriate for the athlete. For partial tears that are operatively treated these may be in acute setting or a healthy ligament that has an avulsion consider a repair with internal brace however a more chronic injury that shows chronic laxity may consider a reconstruction. Well how about PRP? This is a Leuka-Podesta study out of Kerlin-Job that looked at 34 MRI documented partial UCL tears all failed a minimum of two months of non-operative treatment. They looked at typical baseline measures to get back. All had a single PRP injection. The average time to return to play was 12 weeks in this group. All their patient reported outcome scores were improved and 88% overall return to prior performance. Chris Camp and the Major League Baseball study group published this in 2019 looking at 544 non-operatively treated UCL injuries. 133 of these had PRP injections, 411 with no PRP injections. Those who returned to play actually had a higher rate if you did not receive PRP so 57% versus 46% and those that failed non-operative treatment again higher in the PRP group versus the non-PRP group. Overall time to surgery if you did require surgery in the PRP group was shorter than the non-PRP group. Again this is just looking at those that failed versus those that did not have surgery. So use of PRP, the MRI grade and tear location were not statistically significant in this study. There were some limitations. This was a retrospective study. The spectrum of PRP techniques and protocols was not provided. Multiple radiologists reviewing MRI grades of UCL. These are relatively smaller number of grade 2 and 3 injuries for comparison and the percentage of study patients, there was a percentage of study patients who either retired or were released. This was systematic review published in 2019 looking at 7 studies. Return to play after conservative treatment range from 42 to 100%. Components of rehab included periods of rest, stretching, strengthening and thrower programs. PRP was included in 71% of the 7 protocols. Factors such as age, grade of tear, level of play and athlete's perceived well-being all need to be considered when returning to treatment. So in conclusion conservative treatment of partial UCL tears is a viable option. Degree and location of partial tears can guide treatment. Non-surgical treatment options include active rest, shoulder and a core and a kinetic chain program. Non-operative treatment is reserved for higher grade tears, increased ulnar-humeral gapping and failure to respond to non-operative treatment. Repair versus reconstruction, we can certainly consider these as we go further down the road. I thank you very much for your attention.

partial ulnar collateral ligament tears

diagnosis

treatment

athletes

baseball players