FSHP Academy
Human Anatomy — all lessons

Foundations of Anatomy

Anatomical terminology, planes, axes and movement directions

The Skeletal System

Skeletal system: structure and functionsBone structure, remodelling and adaptation to loading

Joints and the Muscular System

Joint types and classificationJoint mechanics: arthrokinematics and stabilityThe muscular system: organisation and major muscle groupsMuscle architecture: pennation, length and cross-sectional areaMuscle fibre types

Regional Functional Anatomy

Spine and postureThe shoulder complexThe hip complexThe knee complexThe ankle and foot complexCore and pelvic stabilityElbow and wrist functional anatomyCervical and thoracic spine functional anatomy

The knee complex

Tibiofemoral and patellofemoral joints, cruciate and collateral ligaments, menisci and the muscles that control the knee — with evidence on valgus, ACL injury and prevention.

Intermediate Evidence: Strong evidence 3 min read Reviewed 2026-10-31 Status: draft

Learning objectives

  • Describe the tibiofemoral and patellofemoral joints and their passive stabilisers
  • Explain the roles of the menisci and the four major ligaments
  • Discuss dynamic knee valgus and its relationship with ACL injury
  • Apply knee anatomy to squatting, landing and change of direction

Before this lesson

Why this matters

The knee sits between two long levers and carries large forces in running, landing and cutting. ACL injuries are among the most consequential in sport. Accurate anatomy and an honest reading of the prevention evidence help trainers coach landing and squatting well.

Fundamental concepts

  • Tibiofemoral joint — femoral condyles on the tibial plateau; a modified hinge with rotation possible when flexed.
  • Patellofemoral joint — the patella glides in the femoral trochlea; as a sesamoid bone it increases the quadriceps’ moment arm.
  • Menisci — medial and lateral C-shaped fibrocartilages that deepen the plateau and spread load.
LigamentMain restraint
ACLAnterior tibial translation; rotation
PCLPosterior tibial translation
MCLValgus (knee pushed inward)
LCLVarus (knee pushed outward)

Muscles: quadriceps (extension), hamstrings (flexion; resist anterior tibial translation), gastrocnemius (flexion), popliteus (unlocks the knee from full extension) [neumann2017].

Knee valgus and ACL injury

Most ACL injuries are non-contact, occurring in deceleration, cutting or landing with the knee near extension and moving into valgus and rotation. In a frequently cited prospective cohort of female athletes, greater knee valgus angles and moments during a drop-jump landing were associated with later ACL injury [hewett2005]. However, a larger later study in elite female players found the drop-jump test was a poor screening tool — it could not identify which individuals would be injured [krosshaug2016].

What does work at group level: neuromuscular training programmes (strength, plyometrics, balance and landing technique) reduce ACL injury rates, as summarised across multiple meta-analyses [webster2018].

Practical application

Common mistakes and misconceptions

Case study

A youth netball club wants ACL screening. The coach explains that screening tests do not reliably predict which individuals will be injured, and instead implements a 15-minute neuromuscular warm-up three times weekly for the whole squad, with coaching on landing and deceleration — the approach with the strongest evidence.

Further learning: video lessons

Video links are only marked “verified” after a human has watched them. Unverified entries open a YouTube search for that channel and topic rather than a guessed link.

Introductory needs verification — opens a YouTube search

Knee joint anatomy

Kenhub

You will understand: bones, ligaments and menisci of the knee

Why: Clear anatomical visuals.
Practical demo needs verification — opens a YouTube search

ACL injury mechanisms and prevention

Oslo Sports Trauma Research Center / FIFA 11+ resources (search)

You will understand: how injuries happen and how prevention programmes work

Why: From the research groups that study ACL injury.

Knowledge check

Knowledge check · 0/5

1. The anterior cruciate ligament mainly resists…

Answer B. The ACL limits anterior translation of the tibia relative to the femur and contributes to rotational stability.

2. The menisci…

Answer A. The C-shaped fibrocartilage menisci deepen the tibial surface and distribute load.

3. In a large prospective study of elite female players, the drop vertical jump screening test…

Answer B. Krosshaug et al. (2016) found the test could not usefully identify players who would later tear their ACL.

4. Allowing the knees to travel past the toes in a squat…

Answer B. Forward knee travel redistributes torque toward the knee; it is a training variable, not a fault in itself.

5. The patella improves quadriceps function by…

Answer A. As a sesamoid bone it displaces the tendon away from the axis, increasing leverage.

Short-answer & application questions

  1. Describe the passive and active stabilisers that resist anterior tibial translation.
  2. Explain why screening tests have limited ability to predict individual injuries but prevention programmes still work at group level.
  3. Plan a progression for teaching landing mechanics to youth netball players.

Key takeaways

  • The knee includes the tibiofemoral and patellofemoral joints, stabilised by cruciate and collateral ligaments, menisci and muscles.
  • The ACL resists anterior tibial translation and rotational loads; most ACL injuries are non-contact (cutting, landing).
  • Dynamic knee valgus during landing was associated with ACL injury in one influential cohort, but screening tests predict injury poorly in larger studies.
  • Neuromuscular training programmes reduce ACL injury rates.
  • “Knees over toes” is not inherently dangerous; it shifts load from hip to knee.

Connected topics

anatomy

The hip complex

anatomy

The ankle and foot complex

corrective exercise

Knee

prehab rehab

Injury prevention programmes

assessment

Limits of movement screens and postural assessment

References

  1. Neumann DA (2017). Kinesiology of the Musculoskeletal System: Foundations for Rehabilitation (3rd ed.). Elsevier. Textbook check pending
  2. Hewett TE, Myer GD, Ford KR, et al. (2005). Biomechanical measures of neuromuscular control and valgus loading of the knee predict anterior cruciate ligament injury risk in female athletes. American Journal of Sports Medicine, 33(4):492–501. doi:10.1177/0363546504269591 Cohort check pending
  3. Krosshaug T, Steffen K, Kristianslund E, et al. (2016). The vertical drop jump is a poor screening test for ACL injuries in female elite soccer and handball players. American Journal of Sports Medicine, 44(4):874–883. doi:10.1177/0363546515625048 Cohort check pending
  4. Webster KE, Hewett TE (2018). Meta-analysis of meta-analyses of anterior cruciate ligament injury reduction training programs. Journal of Orthopaedic Research, 36(10):2696–2708. Meta-analysis check pending

Educational content only — not medical advice. Consult a qualified clinician for diagnosis or treatment.