Table 2

Level of evidence and type of surgery performed in included studies

StudyStudy designLevel of evidenceSubjectsType of surgery
Surgical treatment only (athletes vs matched non-athletes)
Mochida, et al32Retrospective cohort study4Elite athletes vs matched non-athletesPercutaneous nucleotomy/discectomy
Surgical treatment only (athletes vs manual labourers)
Matsunaga, et al33Retrospective cohort study4Club team or professional athletes vs manual labourersPercutaneous discectomy
Surgical treatment only (athletes only)
Sakou et al34Retrospective cohort study4Athletes in various sports participating in national meetsPercutaneous discectomy
Savage, et al37Retrospective cohort study4NFL athletesLD
Watkins and Williams35Retrospective cohort study4Professional and Olympic athletesMicrodiscectomy
Watkins, et al36Retrospective cohort study4Professional athletesMicrodiscectomy
Yoshimoto, et al29Retrospective cohort study4Elite athletesMicrodiscectomy
Surgical vs conservative treatment (athletes only)
Earhart, et al30Retrospective comparative study3bMLB athletesMicrodiscectomy and/or laminotomy/foraminotomy
Hsu26Retrospective cohort study4NFLLD
Hsu, et al27Retrospective cohort study4Elite athletes in NFL, NBA, NHL and MLBLD
Schroeder, et al28Descriptive epidemiological study3bNHL athletesLD
Weistroffer and Hsu31Case series: Retrospective cohort study4NFL linemenOpen or tubular laminectomy
Surgical treatment vs control group (matched asymptomatic athletes without intervention)
Anakwenze, et al25Retrospective case–control3bNBA athletesLD
Wang, et al14Retrospective cohort study4NCAA athletesMicrodiscectomy, percutaneous discectomy
  • LD, lumbar discectomy; NBA, National Basketball Association; NFL, National Football League; NHL, National Hockey League; RTS, return to sport.