Meniscus Surgery: Everything You Might Need to Know

With two prominent players, Mike Trout and J.T. Realmuto, just needing meniscus surgery, I examined hitter production before and after surgery. With a limited sample, some struggles should be expected.

I won’t waste words on fluff and get to the study. First, here is some background information.

• I’m able to search the historical Rotowire notes (2009 to 2023) to get all mentions of meniscus. I missed some players whose regular knee surgeries were meniscus-related but I couldn’t be sure.
• The sample count is on the low side (52 total). Even with the guys I found, several minor leaguers or quad-A talent so I couldn’t match MLB seasons. Since I collected the information, I ran the numbers but I understand if someone just ignores the information.
• I tried to remove all hitters who had another operation simultaneously. For example, Adam Eaton, Andrew McCutchen, and Wilson Ramos had ACL surgeries in addition to meniscus surgery.

Some general notes on the information.

• 45% of the surgeries were to catchers. 39% were Outfielders. A total of 84% from just the two spots.
• The average age at the time of the surgery was 28.3 years (median = 28). Over the time frame, the average age for the league varied from 27.9 to 28.9 so it’s not an older crowd needing to go under the knife.
• The average mid-season return was 58.2 days (median = 54) with the three quickest returns being 19 days (Jay Bruce in 2014) with 33 days and 43 days being the next two fastest. All three of these quick return dates were over ten years ago. The quickest return time since 2014 was Cristian Pache last season who returned in 49 days. Realmuto’s timeline is from 4 to 8 weeks depending on the sources.

With the limited sample of information, here is how hitters performed with the weighted (by PA) and median differences in OPS (18 points of OPS means a 5% change in production). I’d focus on the weighted values.

Notes

• The normal aging from age 27 to 29 is 30 points of OPS. Looking at the first line, the overall change points to hitters bouncing back from the operation once given enough rest and recovery.
• It seems it takes a complete offseason to regain previous production levels. The hitters don’t rebound from preseason and mid-season surgery (lines 2 and 7).
• Hitters tried to play through the injury and their production suffered before getting an operation (line 6). For those returning during the season, don’t expect a major rebound.

In conclusion, expect it to take a couple of months for a hitter to return from the IL, and don’t expect a rebound in production this season. Or ignore the information based on the small sample.