Achilles Tendon Injuries in Major League Soccer: A 10-year Analysis of Injury Rate, Return to Play, and Performance Metrics
Orthopaedic journal of sports medicine · 2026
MLS Achilles ruptures cost 229 days to return, but the flashy position-specific performance findings rest on single-digit subgroup sizes.
The paper
Retrospective matched-cohort study (Level 3), MLS Injury Surveillance database 2010-2021; n=20 Achilles ruptures and n=352 nonruptured Achilles injuries, each compared to uninjured controls matched 2:1 by age, position, and MLS experience.
What they found
Ruptures took a mean 229 days to RTP versus 14.9 days for nonruptured injuries (p<.001, adjusted 95% CI 171-264 days). Younger players (≤26) had longer RTP than older players (303.6 vs 168.1 days, p=.017). The paper also reports position-specific performance subanalyses (e.g. forwards showing declines in games played post-rupture, with goalkeeper-specific clean-sheet and games-played declines reportedly persisting into a second season) drawn from an n=20 rupture cohort split across three positions; exact effect sizes for these subgroups should be checked against the full text before being quoted precisely.
The appraisal
This is a registry-based Level 3 cohort with no blinding possible and RTP decisions made by clubs rather than standardized criteria, so selection and ascertainment bias are real concerns. The headline rupture-vs-nonrupture RTP gap is clinically obvious and not surprising, but the position-specific performance subanalyses split only 20 ruptures into forwards, midfielders and goalkeepers, meaning each subgroup is likely 4-7 players; several reported means carry standard deviations similar in size to the mean itself, which signals a handful of outliers driving 'significant' results rather than a stable effect. No correction for multiple comparisons is mentioned despite testing many outcomes across three positions and two follow-up years.
The gap
The goalkeeper and midfielder subgroup effects need replication in a larger multi-league sample before they mean anything, because with single-digit subgroup sizes one or two players' career trajectories (which can be driven by age, contract status, or team quality rather than tendon healing) can flip the result entirely.
Landmark context
This sits within a growing body of professional-sports Achilles rupture registry studies (NFL, NBA and similar analyses) that consistently show RTP in the 200-260 day range and measurable performance decline afterward; this paper extends that literature to MLS and is the first to break performance outcomes down by soccer-specific position, but it does not overturn or meaningfully add power to the existing evidence base.
What to do Monday
Use the 229-day mean rupture RTP (95% CI 171-264) as a benchmark for setting timeline conversations with players, families and club medical staff, sitting alongside criteria-based progression rather than replacing it. Flag younger players (≤26) as trending toward longer, not shorter, RTP than age alone would predict, which should temper any urge to fast-track return-to-training load in this group. The position-specific performance-decline data (goalkeepers, forwards) comes from an n=20 rupture cohort split three ways and is too underpowered to guide individual case management; use it only as a prompt to extend post-RTP performance monitoring in these roles, not as a prognosis.
In practice
This applies to any elite/sub-elite team-sport athlete post-Achilles rupture, not just MLS players, and to a lesser extent to non-rupture Achilles soreness/tendinosis where the 14.9-day figure confirms these are genuinely minor, fast-turnaround presentations rather than something to over-manage. In the clinic, use 229 days as the conversation-setting number with the athlete and surgeon, but keep discharge criteria-based (calf raise endurance and symmetry, hop testing, tendon loading capacity) rather than date-based, and specifically flag younger players to the surgical and coaching staff as a group who may need more time, not less, since that cuts against the usual assumption that youth heals faster. On the S&C floor, don't restructure programming by position off this paper, the goalkeeper/forward subgroup numbers are too thin to act on, but do use the signal to justify keeping returned players (especially goalkeepers and forwards) in extended late-stage reconditioning and performance monitoring through a second season rather than discharging them from S&C oversight at RTP clearance. The caveat in application: treat the position-specific decline as a reason to watch more closely, not as a basis for load-restriction decisions or team-selection conversations, since a couple of players' contract or role changes could easily be driving the numbers instead of tendon healing.
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