📅 Published on May 162024 | 🕒 Last updated on November 122025
Overview of Leg Anatomy
The legs are a part of the lower limbs of the human bodylocated between the knee and ankle. They play a vital role in supporting body weight and maintaining balance.[1] It also enables movement such as standingwalkingrunningclimbingand even complex activities like dancing or jumping.[1] The parts of leg anatomy comprise several key componentsincluding bonesmusclestendonsligamentsjointsand nerves. They work together to provide strengthflexibilityand coordination.[1][11] The largest bone in the bodythe femur (thigh bone)connects the hip to the knee.[2] Below the kneethe tibia (shin bone) and the thinner fibula form the lower leg.[4][5] The thigh lies between the hip and the kneewhile the calf comprises the back portion of the lower leg.[1] The shin refers to the front part of the lower leg where the tibia is located.[1][4]
Human legs are unique in evolution because they are specially adapted for bipedal locomotion (walking on two feet). This adaptation gives us efficiency in movement compared to most animals.[1][2][19] Anatomical differences exist between male and female legs—for examplein hip angleknee alignmentand bone length—but the overall structure and function remain the same.[17][2]
In this articlewe will explore leg anatomy in detailcovering the major bonesmusclestendonsligamentsjointsand nervesto understand how our legs work and why they are so essential for daily activities and overall mobility.
Leg Anatomy Diagram

Parts of the Leg
Leg Muscles
- Thigh
- Gastrocnemius
- Soleus
- Tibialis Anterior
- Peroneus Longus
- Peroneus Brevis
Tendons
- Achilles Tendon
- Tibialis Posterior Tendon
Ligaments
- Anterior Cruciate Ligament (ACL)
- Posterior Cruciate Ligament (PCL)
- Medial Collateral Ligament (MCL)
- Lateral Collateral Ligament (LCL)
Leg Bone Anatomy
Femur
The femur or thigh bone is the longestheaviestand strongest bone in the human body. It plays a crucial role in supporting body weightmaintaining postureand enabling smooth movements like walkingrunningand jumping.[2][1]
The femur is divided into three main parts:
- Proximal end (upper part): It connects with the hip bone at the hip joint.[2][15]
- Shaft (middle portion): It is the longcylindrical body of the bone.[2][15]
- Distal end (lower part): It connects with the tibia and patella (knee cap) to form the knee joint.[2][15]
The femur also acts as a weight-bearing bonetransmitting forces from the hip to the knee and giving the body strength and stability.[2] It serves as an anchor point for several musclesligamentsand tendons that control leg movement and balance.[15]
Inside the femoral shaftthere are two types of bone marrow:
- Red bone marrow – It is responsible for producing red blood cellswhite blood cellsand platelets (essential for oxygen transport and immunity).[2]
- Yellow bone marrow – It mainly stores fat and serves as an energy reserve.[2]
Because of its strength and vital functionsthe femur is often studied in orthopedicsanatomyand sports medicine to understand mobilityfracturesand overall skeletal health.

Read More – Femur Anatomy: Complete Guide with PartsNamesFunctions & Diagram
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- How to do Femur fracture repair?
- All you need to know about the Femur X-Ray.
Patella
The patella or kneecap is a triangular and flat bone in a central position at the front of the knee joint. It helps to connect the femur and tibia in the knee area.[3][11][16]
The main role of the patella comes during the process of knee extension.[3][11][16] Alsoit has another critical functionwhich is to facilitate the easy movement of the knee during both flexion and extension.[3][11][16]
Additionallyit acts as a protective shield for the anterior surface of the knee jointsafeguarding it from potential harm.[16]
- Patella Fractures: Approach to Treatment.
- Patella fractures treated with suture tension band fixation.
Tibia
The tibiacommonly known as the shin boneis one of the two major bones in the lower leg. It serves as the main weight-bearing bone of the body. It is largerstrongerand more vital for support compared to the fibula.
The tibia connects with the femur at the knee joint and with the fibula and talus at the ankle joint. It is positioned on the inner side of the leg and runs parallel to the fibulastretching from just below the knee down to the ankle.[4]
From a functional perspectivethe tibia is responsible for supporting body weightmaintaining balanceand ensuring stability during standingwalkingand running.[4]
It acts as a crucial link between the thigh and the foot. It allows smooth movement while protecting the internal structures of the leg.[4]
- Cross-Union Surgery for Congenital Pseudarthrosis of the Tibia.
- Knee Pain After Intramedullary Nailing in the Tibia.
- Tibia (Shinbone) Shaft Fractures.
Fibula
The fibula is a longthin bone in the lower leglocated on the outer side next to the larger tibia. Unlike the tibiait does not carry much body weightbut it is essential for leg stabilitybalanceand ankle movement.[5]
- Upper End (Head & Neck): At the topthe fibula has a rounded head just behind the tibia’s headfollowed by a narrow neck.[5]
- Shaft: The middle section of the fibula is called the shaft. It is triangular in shape with three surfaces—lateral (outer)medial (facing the tibia)and posterior (back).
- Lower End (Lateral Malleolus): At the anklethe fibula widens to form the lateral malleolusthe bony bump on the outer side of the ankle. This part connects with the talus bonehelping form the ankle joint and preventing excessive side-to-side movement.
The fibula is tightly linked to the tibia by the interosseous membrane.[5] It is a strong sheet of connective tissue that runs between the two bones.
This connection provides stability and ensures proper leg function during walkingrunningand standing.[5]
- Nutrient foramina of human fibula: morphometric analysis and clinical relevance.
- Innovative approach to intramedullary nailing of the fibula: a technical note.
Leg Muscle Anatomy
Thigh
The thigh is the upper part of the leglocated between the hip and the knee. Its main bone is the femurthe longest and strongest bone in the human body. The femur supports body weight and helps with movement.
The thigh is divided into three main compartmentsand each has its own musclesnervesand blood vessels that work together for movement and stability:
- Anterior Compartment – It contains the quadriceps muscleswhich straighten the knee. They are important for walkingrunningclimbingand kicking.[7][15]
- Medial Compartment – It is known as the adductor group. These muscles pull the legs inward toward the body’s midline. They help with balanceside-to-side motionand controlled leg positioning.[7][15]
- Posterior Compartment – It includes the hamstring muscleswhich bend the knee and extend the hip. These muscles are essential for sittingstandingjumpingand sprinting.[7][15]
All these compartments are separated by a strong connective tissue called fasciawhich gives structureprotectionand support to the thigh muscle.

Read More – Complete Guide to Thigh Muscle Anatomy: Learn PartsNames & Diagram
Gastrocnemius
The gastrocnemius musclecommonly called the calf muscleis one of the largest and strongest muscles in the lower leg. It has two parts (the medial and lateral heads) that start just above the knee and join together at the back of the legattaching to the Achilles tendon at the heel.[6][10]
This muscle crosses three important joints:
- Knee Joint
- Ankle joint
- Subtalar joint (in the foot)
Because it spans multiple jointsthe gastrocnemius plays a key role in leg movement and stability. Its main functions are:
- Plantar flexion – pointing the toes downwardsuch as when standing on tiptoewalkingor pushing off the ground.[6][10]
- Knee flexion – helping bend the knee during movement.[6][10]
These actions make the gastrocnemius essential not only for daily activities like walkingclimbing stairsand standingbut also for athletic movements such as runningsprintingand jumping.
From a muscle fiber perspectivethe gastrocnemius is rich in fast-twitch fiberswhich are designed for quick and powerful movements. This makes the muscle highly effective for bursts of speed and strengththough less suited for long-term endurance compared to muscles with more slow-twitch fibers.[6]
For sportsexerciseand rehabilitationkeeping the gastrocnemius strong and flexible is crucial. Proper strengthening and stretching improve ankle stabilitybalancemobilityand overall athletic performance.
Soleus
The soleus muscle is important in the lower leglocated deep in the calfand works closely with the gastrocnemius muscle. Togetherthese two muscles form the triceps surae.[10]
The soleus has a complex structure. It has many muscle fibers that attach to different places on the leg bones. Most of these fibers start below the knee and go down to the heel bonewhile some start at various spots on the back of the leg bones.[10]
Some of them attach to a flat structure called the anterior aponeurosis.[10] In contrastothers connect to another similar structure called the posterior aponeurosis. This muscle helps us stand and walk.[10]
Tibialis anterior
The tibialis anterior muscle is the largest in the front part of the lower leg. It starts from the upper section of the shin bone (tibia) and extends downward toward the foot.
This muscle performs two main movements:
- Dorsiflexion – lifting the foot upward toward the shin.
- Inversion – turning the sole inward.
Although the tibialis anterior is a muscleit works closely with important foot and ankle bones such as the calcaneus (heel bone)talus (ankle bone)navicularcuneiform bonesand the first three metatarsals.[8][11] Togetherthey make smooth and controlled foot movement possible.
The tibialis anterior is vital for walkingrunningclimbing stairsand balance. It lifts the foot during movementsupports the natural archand helps reduce strain on the lower leg and foot.[8][12]
A strong tibialis anterior is crucial for maintaining healthy gait mechanicsfoot stabilityand preventing injuries. Weakness or injury in this muscle may cause issues such as foot dropshin painor walking instability.[8][12]
Peroneus Longus
The peroneus longus is one of the two main muscles on the outer side of the lower legalong with the peroneus brevis. It is supplied with blood by the fibular artery and branches of the tibial artery. Its movements are controlled by the superficial fibular (peroneal) nervewhich comes from the spinal nerves L5–S2.[3][5]
This muscle begins at the upper and outer surface of the fibula (the long bone of the leg) and extends downward toward the foot. It attaches at the base of the first metatarsal and the medial cuneiform bone near the big toe.[3][5]
Key Functions of the Peroneus Longus
- Plantarflexion – pointing the foot downward.
- Eversion – turning the sole outward.
- Arch support – helping stabilize the transverse arch of the foot.
This muscle works together with the peroneus brevis & ensures smooth foot movementsbalanceand stability during walkingrunningand side-to-side activities.[3][5]
The peroneus longus can be affected by:
- Strains or tears – often from sudden twisting motions.
- Tendonitis – inflammation caused by overuse or repetitive stress.
- Ankle sprains – especially in sports like basketballfootballor running.
Symptoms may include pain in the outer ankleswellingweaknessor difficulty moving the foot.
Peroneus Brevis
The peroneus brevis is an important muscle on the outer side of the lower leg. It is located just beneath the peroneus longus.
Its main role is to help turn the foot outward (eversion) and point the toes downward (plantar flexion). These movements are essential for walkingrunningand keeping proper balance.[9][5]
This muscle gets its nerve supply from the superficial peroneal nerve and its blood supply from the peroneal artery.
It begins from the lower part of the fibula (the thin bone on the outside of the leg) and attaches to the base of the fifth metatarsal bone on the outer edge of the foot.[9][5]
Unlike the longer and slimmer peroneus longusthe peroneus brevis is shorter and thickerwhich makes it more stable. Its tendon runs slightly above the outer ankle bone (lateral malleolus)curves around the ankleand firmly attaches to the fifth metatarsal.
This strong attachment helps stabilize the ankle and protects it from common injuries such as ankle sprains.[9][5]

Read More – Hip Muscle Anatomy – Complete Guide with PartsNamesFunctions & Diagram
Leg Anatomy: Joint
Hip Joint
The hip joint is also known as a ball-and-socket joint. It has a “ball” at the top of the thigh bone (femur) that fits into a “socket” in the hip bone (acetabulum).[13]
This design allows the hip joint to move in many directions. It can bend and straighten (flexion and extension)rotate (internal and external rotation)and move sideways (abduction and adduction).
One of the primary functions of the hip joint is to support the body’s weight when standingwalkingor running. It also helps transfer force from your upper body to your legsallowing you to move.[13]
The hip joint is strong and stablepartly because of the deep socket that holds the femur in place. There is also a ring of tough cartilage called the acetabular labrum around the edge of the socketwhich helps keep the joint secure.[13]
This cartilage has a few important roles:
- It helps spread the pressure when you put weight on your hips.
- It creates a suction that helps keep the joint stablelike a vacuum seal.
- It also helps control the fluid flow that lubricates the jointwhich keeps everything moving smoothly.

Read More – Hip Bone Anatomy – Complete Guide with PartsNamesFunctions & Diagram
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- What is Hip Replacement Surgery & why is it needed?
- How to do a Hip joint replacement?
- What are Hip Injuries and Disorders?
- How to take care of your new hip joint?
- What are the Hip Dislocation treatments?
Knee Joint
The knee is the largest joint in our body. It mainly operates as a hinge for bending and straightening the leg. Its structure involves two key articulations: the tibiofemoral and patellofemoral jointswhich create a compound synovial joint together.[18][15]
This joint is essential for efficient walkingrunningand jumping. The bones involved in knee articulation are complex.
The femur has a slight inward slantwhile the tibia is almost vertical. The patellathe largest sesamoid bone in the bodysits at the front of the knee. It serves as the endpoint for the quadriceps tendon and shields the front surface of the femur.[18][15]
The articulating surfaces at the knee include the lateral and medial condyles of the femur and tibiaand the front-to-back connection between the patella and femur.[18]

Read More – Knee Anatomy: Complete Guide to PartsNamesFunctions & Diagram
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- What are the Knee Injuries and Disorders?
- How to do a Knee Replacement?
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- How To Do Knee Arthrocentesis?
Ankle Joint
The ankle joint is formed by joining three bones: the talustibiaand fibula. It is a socket where the talus bone sitssurrounded by the tibia and fibula. The bony prominence on the lower fibulathe malleolihelps form the edges of this joint.[5][11]
During walkingthe ankle adjusts to different surfaces. It can move in four main ways: pushing your toes down (plantarflexion)pulling them up (dorsiflexion)tilting the sole of your foot inwards (inversion)or tilting it outwards (eversion).[5][11]
- What is Ankle Pain? Causes & Care.
- How to do an Ankle Replacement?
- What are the Ankle Injuries and Disorders?
- What is an Ankle Fracture & how to diagnose it?
Subtalar Joint
The subtalar joint is also known as the talocalcaneal joint. It is where the talus bone and the calcaneus bone meet in the foot.
There are three points where they connecttwo in the front and one in the back. These connection points are called facetswith one at the backone in the middleand one in the front.[11]
At the front and middle connectionsthe shape of the talus fits into the shape of the calcaneuswith the talus being convex and the calcaneus being concave. In the back connectionthe talus is concaveand the calcaneus is convex.[11]
The middle connection has a structure called the sustentaculum tali as its floorand the front connection fits snugly against the head of the talus.
Sometimesthe middle and front connections are combined into one. The back connection is the largest and is separated from the others by a tarsal canal structure.
This joint allows the foot to move from side to side (inversion and eversion). Howeverit does not have much to do with moving the foot up or down (dorsiflexion or plantarflexion).[11]
FAQ’s
The human leg consists of bones (femurtibiafibulapatella)muscles (quadricepshamstringscalf musclestibialis anteriorperoneal musclesetc.)joints (hipkneeanklesubtalar)ligamentstendonsblood vesselsand nerves.[1][4][5][7][11]
Each lower limb’s main long bones include the femurtibiafibulaand patellaplus numerous tarsalmetatarsaland phalangeal bones in the foot. The major weight-bearing leg bones are the femurtibiafibulaand patellareferenced above.[1][4][5]
Major leg muscles include the quadriceps and hamstrings in the thighand the calf muscles (gastrocnemius and soleus)tibialis anterior in the anterior compartmentand the peroneal (fibularis) muscles in the lateral compartment; additional deeper muscles control toe and foot movements.[7][6][8][9]
The tibia is commonly called the shin bone because it forms the front portion of the lower leg. It bears most of the body’s weight and connects the knee to the ankle.[4]
The tibia is largerweight-bearingand forms the shin. The fibula is thinnerlies beside the tibiaand provides stability to the ankle but does not bear much weight.[4][5]
The sciatic nerve is the largest nerve supplying the leg. It branches into the tibial and common peroneal nerveswhich control movement and sensation in the thighcalfand foot.[14][20]
Leg muscles (quadricepshamstringscalvesglutealsand intrinsic foot muscles) stabilize joints and coordinate movements that maintain posture and enable safebalanced gait and stance.[6][11][20]
References-
- Berry Ket al. (2024). AnatomyBony Pelvis and Lower Limb: Leg Bones. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK537024/
- Berry Ket al. (2023). AnatomyBony Pelvis and Lower Limb: Femur. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK532982/
- Lezak BVaracallo M. (2023). AnatomyBony Pelvis and Lower Limb: Calf Peroneus Longus Muscle. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK546650/
- Johnson ECet al. (2023). AnatomyBony Pelvis and Lower Limb: Tibia. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK526053/
- Gupton Met al. (2023). AnatomyBony Pelvis and Lower Limb: Fibula. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK470591/
- Bordoni Bet al. (2023). AnatomyBony Pelvis and Lower Limb: Gastrocnemius Muscle. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK532946/
- Berry Ket al. (2022). AnatomyBony Pelvis and Lower Limb: Thigh Muscles. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK482445/
- Juneja Pet al. (2023). AnatomyBony Pelvis and Lower Limb: Tibialis Anterior Muscle. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK513304/
- Khawaji MTet al. (2023). AnatomyBony Pelvis and Lower Limb: Foot Peroneus Brevis Muscle. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK535427/
- Binstead JTet al. (2023). AnatomyBony Pelvis and Lower Limb: Calf. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK459362/
- Manganaro Det al. (2023). AnatomyBony Pelvis and Lower LimbFoot Joints. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK536941/
- Juneja PHubbard J. (2023). AnatomyBony Pelvis and Lower Limb: Tibialis Anterior Muscles. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK513304/
- Gold Met al. (2023). AnatomyBony Pelvis and Lower LimbHip Joint. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK470555/
- Machi Met al. (2023). AnatomySciatic Nerve. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK482431/
- Cleveland Clinic Medical Education Team. (2022). Femur (Thighbone): AnatomyFunction & Common Conditions. Cleveland Clinic. https://my.clevelandclinic.org/health/body/22503-femur
- Berry KVaracallo M. (2023). AnatomyBony Pelvis and Lower LimbKneePatella. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK519534/
- Tetsworth Ket al. (2017). Gender-related differences in lower limb alignmentrange of joint motionand the incidence of sports injuries in Japanese university athletes. Knee Surg Sports Traumatol Arthrosc. PMC. https://pmc.ncbi.nlm.nih.gov/articles/PMC5300795/
- Berry Ket al. (2023). AnatomyBony Pelvis and Lower LimbKnee. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK500017/
- Lovejoy COSuwa MSpurlock Let al. (2009). Fossilsfeetand the evolution of human bipedal locomotion. J Anat. PMC. https://pmc.ncbi.nlm.nih.gov/articles/PMC1571304/
- Varacallo Met al. (2023). AnatomyBony Pelvis and Lower Limb: Nerves. StatPearls. NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK532304/
Read More-
Lower Limb
- Hip Bone Anatomy – Complete Guide with PartsNamesFunctions & Diagram
- Complete Guide on Leg Anatomy with PartsFunctions & Diagram
- Complete Guide to Thigh Muscle Anatomy: Learn PartsNames & Diagram
- Knee Anatomy: Complete Guide to PartsNamesFunctions & Diagram
- Femur Anatomy: Complete Guide with PartsNamesFunctions & Diagram
- Hip Muscle Anatomy – Complete Guide with PartsNamesFunctions & Diagram
Upper Limb
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- Wrist Anatomy: Ultimate Guide to PartsNamesFunctions & Diagram
- Complete Guide to Nail Anatomy with all PartsNames & Diagrams
- Spine Anatomy: Complete Guide with PartsNamesFunctions & Diagram
Official websites of the United States government.
- How to do a Leg MRI scan?
- AnatomyBony Pelvis and Lower Limb: Leg Bones
- Leg skeletal anatomy
- What is Restless Legs Syndrome?
- How To Measure Compartment Pressure in the Lower Leg
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