Clinical Anatomy for Athletic Therapists: Foot, Leg, and Ankle Assessment

Recap and Course Orientation

The course recap highlights the diverse background of the students, noting that the time since their last anatomy course ranges from the previous semester to six years ago. The instructor emphasizes themes of kindness and patience among peers, particularly when practicing clinical and athletic therapy skills. Assessment data from a pre-course survey indicates varying levels of perceived knowledge. Students rated their confidence in identifying anatomical structures (bones, joints, muscles), identifying muscle origins, insertions, and innervations, performing surface palpation, classifying joints, and describing movements using planes and axes ($100\%$ range in responses). Practical skills such as performing Range of Motion (ROM), Manual Muscle Testing (MMT), posture observation, gait analysis, and applying anatomy to clinical scenarios also showed a spectrum of comfort levels. Regarding peer interaction, students reported varying comfort levels with practicing skills on peers, being assessed by peers, and working in small groups. Furthermore, the class average for the first quiz was a remarkably high $97.69\%$ with a standard deviation of $5.04\%$. A specific review question addressed the tarsal bone most likely involved in plantar fasciitis, which is the calcaneus. Plantar fasciitis involves the connective tissue band on the plantar surface stretching from the calcaneus to the base of the metatarsals, supporting the arch and acting like a spring. Pain is often associated with the pull on the calcaneus.

Learning Objectives

The primary goals for this session involve the observation of basic gait and functional movement patterns as they relate to foot and ankle function. Students are expected to perform surface anatomy palpation of key structures with improved accuracy and measure ankle and foot ROM using standardized goniometric techniques. Additionally, the objectives include performing MMT for major ankle and foot muscle groups using appropriate positioning, stabilization, and grading procedures. Finally, students must document findings from palpation, ROM, and MMT using appropriate clinical terminology and structured charting.

Clinical Case Study: The Soccer Player

A initial case study concerns a $19$-year-old soccer player who rolled their ankle during a game. By the next morning, they reported pain on the outside of the ankle and were walking with a limp. Five days later, the player presents with stiffness, difficulty squatting, pain descending stairs, and a feeling of the ankle being "blocked." Initial considerations involve identifying movement abnormalities (limping, swelling causing decreased ROM), identifying affected structures (such as the Anterior Talofibular Ligament or ATFL), and determining assessment priorities. Clinicians should observe movement, follow with anatomical knowledge to identify involved joints (such as the talocrural and subtalar joints), and then select palpation and assessment techniques to identify specific tissue restrictions or weakness.

Functional Demands of the Lower Extremity

The lower leg, ankle, and foot are essential for movement, force absorption, balance, stability, and propulsion during physical activity. These structures face repetitive loading, high-impact forces during running and jumping, and rapid directional changes or cutting. There are three primary functional demands: absorption, propulsion, and stability. Absorption involves controlling forces during heel strike, landing, and deceleration. This requires eccentric muscle control, joint motion, and tissue deformation, such as knee flexion during landing or pronation during gait. Propulsion occurs when muscles contract concentrically to generate force, pushing the body forward, examples of which include push-off during gait, sprint acceleration, and jump takeoffs. Stability, specifically dynamic stability, is the ability to maintain alignment and control movement while transitioning between absorption and propulsion. This is facilitated by muscles, tendons, ligaments, and neuromuscular control. In a clinical context, gait assessment allows professionals to see how force is absorbed, how movement is generated, and how stability is maintained. Abnormalities in these functions contribute to pain, compensation patterns, reduced performance, and increased injury risk. Common injuries include lateral ankle sprains, muscle strains, fractures, and overuse injuries, with repeated sprains potentially leading to chronic instability.

Anatomy and Mechanics of the Gait Cycle

Gait assessment provides clues about injury risk and movement dysfunction. Efficient gait depends on smooth transitions between absorption, propulsion, and stability. The gait cycle consists of two main phases: the Stance Phase ($\approx 60\%$) and the Swing Phase ($\approx 40\%$). During the Stance Phase, the foot is in contact with the ground and undergoes a sequence of absorption, stability, and then propulsion. Weight acceptance requires absorption, while single limb support involves transitioning from absorption to stability and then propulsion. The specific stages of the Stance Phase include: Initial Contact (hip flexed, knee extended, ankle dorsiflexed, and foot supinated for heel strike), Loading Response (foot lowers to the ground via controlled eccentric plantarflexion, foot pronates to absorb force, and the hip and knee eccentrically flex), Midstance (stability phase where the contralateral limb enters swing, requiring high frontal and transverse plane stability from the trunk, hip abductors, and external rotators), and Terminal Stance (propulsion phase where the heel rises and hip extensors and triceps surae—specifically the gastrocnemius—concentrically propel the body forward over the forefoot via the plantar fascia). The Swing Phase involves limb advancement and placement. Its stages include: Preswing (begins with initial contact of the opposite limb, marking double limb support), Initial Swing (foot leaves the ground, gastrocnemius assists knee flexion), Midswing (limb advances in front of the stance limb, and the anterior compartment concentrically dorsiflexes the ankle and supinates the foot for clearance), and Terminal Swing (knee extends, transitioning from propulsion to absorption, where hamstrings and hip extensors decelerate tibial progression in preparation for heel strike).

The Three Major Rockers of Gait

Clinical observation focuses on three major rockers which facilitate smooth movement. The Heel Rocker controls forward momentum for initial absorption. The Ankle Rocker involves the tibia progressing over the foot through controlled dorsiflexion and pronation. The Forefoot Rocker occurs as the heel rises, creating a rigid lever for propulsion. While walking utilizes all three rockers, running typically reduces or eliminates the heel rocker. Clinicians observe variables such as step width and length; a wide base of support or reduced step length can indicate poor balance, pain, or weakness. Excessive pelvic drop (Trendelenburg gait) often suggests weak hip abductors (gluteus medius). Movement quality should be smooth, symmetrical, and quiet; loud ground contact suggests poor eccentric control or reduced absorption capacity. Common deviations include Drop Foot Gait (poor dorsiflexion during swing leading to toe drag or foot slap) and Antalgic Gait (reduced stance time on a painful limb). Most abnormalities occur during the stance phase.

Postural Assessment Principles

Ideal alignment is assessed from anterior, sagittal, and posterior views. From the anterior view, the head should be neutral, the shoulders level, the pelvis level (ASIS in the same transverse plane), and the knees and ankles neutral without excessive valgus, varum, inversion, or eversion. In the sagittal view, the plum line should be in line with the malleolus. Landmarks include a normal cervical curve (convex anteriorly), scapulae flat against the thorax, and a neutral pelvis. The posterior view requires a straight spine, level PSIS, and vertical tendo calcaneus. Faulty postures include pronated feet, which often coincide with medial rotation of the femur (inward-facing patellae), and supinated feet, where weight is borne on the lateral borders and the long arches are higher than normal. Clinicians utilize these observations alongside patient history to guide rehabilitation.

Clinical Palpation and ROM Definitions

Palpation must be performed bilaterally to assess eight specific factors: temperature (for infection or blood flow issues), swelling (dips in skin or growths), point tenderness (painful areas), crepitus (crunching sensations indicative of fractures or air), deformity (inflammatory growths), muscle spasm (tightness), cutaneous sensation (sharp or dull), and pulses (circulation issues such as compartment syndrome). Range of Motion (ROM) measurement involves goniometry, which quantifies joint angles. Osteokinematics refers to the gross movement of bones (e.g., ankle dorsiflexion), while Arthrokinematics refers to the motion between joint surfaces, classified by the convex-concave rule. If a convex surface moves on a concave one, roll and glide occur in opposite directions; if concave moves on convex, they occur in the same direction. ROM includes Active (AROM), Passive (PROM), and Active-assisted (AAROM). A clinical pearl notes that full PROM with limited AROM suggests weakness or neural issues, while limitations in both suggest joint or tissue restriction. Pain in AROM but not PROM indicates contractile (muscle) tissue involvement.

Joint End Feels and Restrictions

End feels provide diagnostic information regarding the quality of resistance at the end range of motion. Normal end feels include: Soft (soft-tissue approximation, e.g., elbow flexion), Firm (muscular, capsular, or ligamentous stretch, e.g., hip extension or forearm supination), and Hard (bone-to-bone contact, e.g., elbow extension). Abnormal end feels include: Boggy (soft-tissue edema), Early Firm (increased muscle tonus or shortening), Bony Block (hard feeling sooner than expected due to fracture or osteoarthritis), and Empty (no resistance felt because the patient stops the movement due to intense pain from acute inflammation or bursitis). Restricted motion can follow a Capsular Pattern, which is a predictable proportional restriction involving the entire joint capsule, or a Non-Capsular Pattern, which indicates a specific structural involvement. Muscle length also influences ROM; for example, the hamstrings may limit hip flexion when the knee is extended, a concept known as passive insufficiency.

Goniometric Measurement Protocols

For the Talocrural Joint (Ankle), Dorsiflexion (non-weight bearing) has a normal ROM of $15-20\,^\circ$. The patient sits with the knee flexed to $90\,^\circ$ and the foot at $0\,^\circ$. The clinician stabilizes the tibia and fibula and pushes on the bottom of the foot, avoiding the 5th metatarsal. The fulcrum is the lateral malleolus, the proximal arm is the midline of the fibula aligned with the head, and the distal arm is parallel to the 5th metatarsal. The end feel is firm. Plantarflexion has a normal ROM of $45-50\,^\circ$. The clinician pushes downward on the dorsum of the foot, avoiding inversion or eversion. The goniometer alignment remains the same as dorsiflexion. The end feel is firm or hard (contact between the talus and tibia). For the Subtalar Joint, Inversion has an active ROM of $5-15\,^\circ$ and passive ROM of $25\,^\circ$. The patient is prone with the foot over the edge. The fulcrum is over the posterior malleoli, the proximal arm is the posterior midline of the leg, and the distal arm is the posterior midline of the calcaneus. The end feel is firm. Eversion has an active ROM of $8-9\,^\circ$ and passive of $12\,^\circ$. The calcaneus is pulled laterally, and the end feel is hard (calcaneus to sinus tarsi) or firm (deltoid ligaments).

Manual Muscle Testing (MMT) Grading

The MMT grading system ranges from $0$ to $5$. A grade of $5$ (Normal) represents complete ROM against gravity with maximal overload. $4$ (Good) is complete ROM against gravity with moderate overload. $3+$ (Fair +) is complete ROM against gravity with minimal overload. $3$ (Fair) is complete ROM against gravity with no overload. $3-$ (Fair -) means the patient initiates motion against gravity or has some but not complete ROM. $2+$ (Poor +) indicates complete ROM with some assistance and gravity eliminated. $2$ (Poor) means the patient can only initiate motion if gravity is eliminated. $1$ (Trace) shows evidence of slight muscular contraction but no joint motion. $0$ (Zero) indicates no muscle contraction is palpated. Testing instructions require defining the individual muscle’s origin, insertion, innervation, and action, followed by appropriate hand positioning and stabilization to isolate the target muscle.