Postural Assessment The ability to perform a postural evaluation accurately and thoroughly requires many skills on the part of the individual. The examiner must be able to separate the parts of the body from the whole and in turn assess the sum of these parts, in reference to their interaction in the entire anatomical structure. In correct posture, the gravity line passes through the axes of all joints, with the body segments aligned vertically. The gravity line is represented by a vertical line drawn through the body’s center of gravity, located at the second sacral vertebra (S2). The gravity line is an ever-changing reference line that responds to the constantly altering body position during upright posture. Although the gravity line generally does not pass through all joint axes of the human body, persons with excellent posture may come close to fulfilling that criterion. Therefore, the closer a person’s postural alignment lies to the center of all joint axes; the less gravitational stress is placed on the soft tissue components of the supporting system.
The strength and length of muscles involved in joint motion must be balanced. The balance is based on force couple (two or more translatory forces that in combination produce rotation) principle among muscles involved in the three cardinal planes of motion. When a force couple is out of balance, the segment moves off its axis of rotation and there is faulty joint motion. The head, trunk, shoulders and pelvic girdle serve as the foundations, from which forces are directed to the limbs.
Postural faults can be used as guidelines for identifying alterations in muscle and ligament length. This may occur when one muscle groups becomes tight and the antagonist elongated. Synergistic muscles around a joint may be unbalanced as well as the agonists.
Minor alignment faults in posture limit motion and lead to tightness of muscles and other soft tissues. Muscles that are elongated often develop their maximal force in the stretched position and are weak in the normal physiological position. Kendall calls this condition stretch weakness.
Alignment of body segments should be observed while the person is standing still and during such movements as walking, to detect faulty patterns of muscle activity and joint mobility. The better the quality of movement and the better the alignment of gravitational forces through joint’s axes, the better is the sequence of motion. When postural alignment improves, imbalances are minimized.
A systematic approach to postural analysis involves viewing the body’s anatomical alignment relative to a certain established reference line. This reference (gravity) line serves to divide the body into equal front and back halves and to bisect it laterally. In preparing to carry out postural assessment, the examiner should be aware of factors that will enhance the success and validity of the examination process. These factors are:
1. Postural assessment must be performed with the subject minimally clothed, in order to ensure a clear view of the contours and anatomical landmarks used for reference.
2. The examiner should instruct the subject to assume a comfortable and relaxed posture.
3. Subjects who use orthotic or assistive devices should be assessed with and without them to determine their effectiveness in correcting posture.
4. The examiner should note relevant medical history and other information that may account for certain postural abnormalities. Important information includes:
- Any history that accounts for present postural abnormalities.
- A complete description of present symptoms.
- All previous treatments for the presenting postural complaints, including orthopedic and neurological therapy.
- The upper limb dominance of the subject, which is often responsible for symptomatic postural deviations.
Postural examination is most commonly performed by assessing the body’s alignment in lateral, posterior and anterior views.
1) Standing Posture a) Lateral View
Lateral postural assessments should be performed from both sides to detect and rotational abnormalities that might go undetected if observed from only one lateral perspective. Ideally, the plumb line should pass through the ear lobe and shoulder joint.
1. Head and neck:
Plumb line: The line falls through the ear lobe to the acromion process. Common faults include:
* Forward head: The head lies anterior to the plumb line. It may be due to:
Plumb line: It falls midway between shoulders. Common faults include:
* Dropped shoulder: One shoulder is lower than the other. It may be due to:
- Hand dominance (dominant shoulder is lower).
- Lateral trunk muscles are short and hip is high and adducted.
- Tightness of the rhomboid and latissimus dorsi muscles.
* Elevated shoulder: One shoulder is higher than the other. This may be due to:
- Tightness in the upper trapezius and levator scapulae muscles on one side; hypertrophy may be noticed on the dominant side.
- Elongated and weak lower trapezius and pectoralis minor.
- Scoliosis of the thoracic vertebrae.
* Shoulder medial rotation: The medial epicondyle of the humerus is directed posteriorly. It may be due to:
- Joint limitation in lateral rotation.
- Tightness of the medial rotator muscles.
* Shoulder lateral rotation: Olecranon process faces posteriorly. It may be due to:
- Joint limitation in medial rotation.
- Tightness of the lateral rotators.
* Adducted scapulae: The scapulae are too close to the midline of the thoracic vertebrae. It may be due to:
- Shortened rhomboid muscles.
- Stretched pectoralis major and minor muscles.
* Abducted scapulae: The scapulae have moved away from the midline of the thoracic vertebrae. It may be due to:
- Tightness of the serratus anterior muscle.
- Lengthened rhomboid and middle trapezius muscles.
* Winging of the scapulae: The medial borders of the scapulae lift off ribs. It may be due to:
- Weakness of the serratus anterior.
Plumb Line: The line bisects the spinous process of the thoracic and lumbar vertebrae. Common faults include:
* Lateral deviation (Scoliosis): The spinous processes of the vertebrae are lateral to the midline of the trunk.
- Intrinsic trunk muscles are shortened on one side.
- Contralateral intrinsic trunk muscles are lengthened.
- Compression of vertebrae on the concave side.
- Structural changes in rips or vertebrae.
- Leg-length discrepancy and obliquity.
- Internal organ disorders.
4. Pelvis and Hip:
Plumb line: The line bisects the gluteal cleft and the posterior superior iliac spines are on the same horizontal plane; the iliac crests, gluteal folds and greater trochanters are level. Common faults include:
* Lateral pelvic tilt:One side of the pelvis is higher than the other due to:
- Scoliosis with ipsilateral lumbar convexity.
- Leg-length discrepancies.
- Shortening of the contralateral quadrates lumborum.
- Tight ipsi-lateral hip abductor muscles on the same side and tight contralateral hip adductor muscles.
- Weakness of the contralateral abductor muscles.
* Pelvic rotation: The plumb line falls to the right or left of the gluteal cleft. It may be due to:
- Tightness of medial rotator and hip flexor muscles on the rotated side.
- Ipsilateral lumbar rotation.
Abducted hip: The greater trochanter is higher on the involved side. It may be due to:
- Tightness of the hip abductor muscles.
- Tightness of contralateral hip adductor muscles.
- Weakness of contralateral adductors and ipsilateral abductors.
Plumb Line: The plumb line lies, equidistant between the knees. Common faults include:
Genu varum: The distal segment (leg) deviates toward midline in relation to the proximal segment (thigh); the knee joint lies lateral to the mechanical axis of the lower limb. It may be due to:
- Tightness of medial rotator muscles at the hip with hyper-extended knees, quadriceps and foot evertor muscles.
Genu Valgum: The mechanical axis for the lower limbs is displaced laterally. It may be due to:
- Tightness of ilio-tibial band and the lateral knee joint structures.
- Femoral ante-version.
- Lengthened medial knee joint structures.
- Compression of lateral knee joint.
- Foot pronation.
6. Ankle and Foot:
Plumb line: The line is equidistant from the malleoli, a line (Feiss’) is drawn from the medial malleolus to the first metatarsal bone and the tuberosity of the navicular bone lies on the line. Common faults include:
Pes planus (Pronated): There is decreased medial longitudinal arch, the Achilles tendon is convex medially and the tuberosity of the navicular bone lies below the Feiss line. It may be due to:
- Structural displacement of the talus, calcaneus and navicular bones.
Pes Cavus (supinated): The medial longitudinal arch is high and the navicular bone lies above Feiss’ line. It may be due to:
Shortened posterior and anterior tibial muscles.
Elongated peroneal and lateral ligaments.
c) Anterior View
Relationships can be posturally assessed from the anterior view with the plumb line bisecting the body into equal left and right halves.
1. Head and Neck:
Plume Line: The line bisects the head at the midline into equal halves. Common faults include:
Lateral Tilt: See section on posterior view.
Rotation: See section on posterior view.
Mandibular asymmetry: The upper and lower teeth are not aligned and the mandible is deviated to one side. It may be due to:
- Tightness of the mastication muscles on one side.
- Stretched mastication muscles on the contralateral side.
- Mal-alignment of temporo-mandibular joints.
- Mal-alignment of teeth.
Plumb Line: A vertical line bisects the sternum and xiphoid process. It may be due to:
Dropped ore elevated shoulder: See section on posterior view.
Clavicle and joint asymmetry: It may be due to:
- Prominences secondary to joint trauma.
- Subluxation or dislocation of sterno-clavicular or acromio-clavicular joints.
- Clavicular fractures.
A line bisects the upper limbs and forms an angle of 5° to 15° laterally at the elbow with the elbow extended. This angle is normal and is referred to as the carrying angle. Common faults include:
Cubitus valgus: The forearm deviates laterally from the arm at angle greater than 15° (female) and 10° (male). It may be due to:
- Elbow hyperextension.
- Distal displacement of trochlea in relation to capitulum of humerus.
- Stretched ulnar collateral ligament.
Cubitus varus: The forearm deviates medially (adducts) from the arm, at an angle of less than 15° for females and 10° for males. It may be due to:
- Fracture about the elbow joint.
- Inferior displacement of the humeral capitulum.
- Stretched radial collateral ligament.
Plumb line: Common faults include:
Lateral rotation: The patellae angle out. It may be due to:
- Tightness of the lateral rotators and gluteus maximus muscles.
- Weakness of the medial rotator muscles.
- Femoral retroversion.
- Internal tibial torsion (compensated).
Medial rotation: The patellae face inward. It may be due to:
- Tightness of the ilio-tibial band and the medial rotator muscles.
- Weakness of the lateral rotator muscles.
- Femoral ante-version.
- External tibial torsion (compensated).
Plumb Line: The legs are equidistant from a vertical line through the body. Common Faults include:
External tibial torsion: Normally, the distal end of the tibia is rotated laterally 25° from the proximal end. Excess of 25° rotation is an increase in torsion and is referred to as lateral tibial torsion (toeing out). It may be due to:
- Tightness of the tensor fasciae latae muscle or ilio-tibial band.
- Bony mal-alignment.
- Cruciate ligament tear.
- Femoral retroversion.
Internal tibial torsion: The feet face directly forward or inward.
- Tightness of the medial hamstring and gracilis muscles.
- Structural deformities of the tibia (traumatic or developmental).
- Anterior cruciate ligament tear.
- Femoral ante-version.
- Foot pronation.
- Genu valgus.
6. Ankle and Foot:
Plumb line: Common Faults include:
Hallux valgus: Lateral deviation of the first digit at the metatarso-phalangeal joint. It may be due to:
- Excessive medial bone growth of the first metatarsal head.
- Joint dislocation.
- Tight adductor hallucis muscle.
- Stretched abductor hallucis muscle.
Claw toes: Hyperextension of the metatarso-phalangeal joint and flexion of the proximal interphalangeal joints, associated with pes cavus. It may be due to:
- Tightness of the long toe flexors.
- Shortness of the toe extensor muscles.
Hammer toes: Hyperextension of the metatarsophalangeal joints and distal interphalangeal joints and flexion of the proximal interphalangeal joints. It may be due to:
- Shortness of the toe extensors.
- Lengthened lumbricals.
2) Sitting Posture
Hip and Pelvis:
Observation: The pelvis assumes a posterior tilt with the posterior inferior iliac spines in the same horizontal plane as the superior pubic ramus. Common faults include:
Posterior pelvic tilt: The superior pubic ramus is superior to the posterior inferior iliac spines. It may be due to:
- Lumbar vertebrae flexed excessively.
- Tightness of the hamstring muscles.
- Elongated low back extensors.
Anterior pelvic tilt: The superior pubic ramus lies inferior to the posterior inferior iliac spine. It may be due to: