Lower Extremity Dysfunction (LED): Predictive Model of Lower Extremity Movement Impairment

“Lower Extremity Dysfunction (LED)" is an edit and update of previous postural dysfunction models (e.g. lower body posture, lower-crossed syndrome, pronation distortion, functional knee valgus, etc.). It is important to recognize that in these models the term "posture" is being used as an analogy for "ideal alignment". Similarly, when movement professionals refer to lower body posture, good posture, poor posture, better posture, etc. they are referring to this analogy of ideal alignment; not the rigid positioning implied by the colloquial use of the term "posture."

Postural dysfunction and movement impairment syndromes are likely the beginning of "modeling". Modeling has significant potential to aid in refining clinical decision-making, intervention selection, program design, and improve the reliability and effect size of outcomes. Models are especially conducive for assisting in interpreting multi-variant problems, which is how all clients and patients present. The Brookbush Institute recommends that all sports medicine professionals (personal trainers, fitness instructors, physical therapists, massage therapists, chiropractors, occupational therapists, athletic trainers, etc.) consider these models as an aid in refining decision-making in practice.

Additional Models:

• Upper Body Dysfunction (UBD)
• Lumbo Pelvic Hip Complex Dysfunction (LPHCD)

Definitions:

• Posture: Arthro- and osteo-kinematics alignment maintained by optimal myofascial activity and length, as a result of sensation, integration, and activation by the nervous system - both statically and dynamically.
• Postural Dysfunction: The absence of ideal posture as a result of maladaptation by one or multiple tissues within the human movement system.
  • Brookbush Institute Modern Definition: Modeling patterns of movement impairment correlated with orthopedic dysfunction, based on all available evidence, with the intent of predicting best-practice assessments and techniques, to optimize measured outcomes.

Summary:

Fascia (Reduction in Extensibility)

Myofascial Synergies (Altered Recruitment)

Arthorkinematics

Signs of Dysfunction

Overhead Squat Assessment :

• Feet flatten
• Feet turn-out
• Knees bow-in
• Knees bow-out
• Excessive lordosis (Anterior pelvic tilt)
• Excessive forward lean
• Asymmetrical Weight Shift

Goniometric Assessment

• Hip Internal Rotation at 90 Degrees of Hip Flexion < 35-45°
• Hip External Rotation at 90 Degrees of Hip Flexion < 35-45°
• Hip Extension < 0-10°
• Knee Extension with Hip Flexion (Hamstring Length  Test ) < 0-20°
• Dorsiflexion < 15-20°

Muscle Length Tests

• Ely's Test (Rectus Femoris )
• Ober's Test (Tensor Fasciae Latae )
• Thomas' Test (Iliacus/Psoas )
• Hamstring Length Test
• Gastroc/Soleus Length Test

Manual Muscle Tests

• Gluteus Medius
• Gluteus Maximus
• Tibial Internal Rotators
• Tibialis Posterior
• Tibialis Anterior

Correlated Injuries, Pathologies, and Pain

The Lower Extremity Dysfunction (LED) model is constructed based on research demonstrating the maladaptive alterations of tissues and motion associated with common impairments of the human movement system. Creating a list of these impairments adds to the definition of the LED model, as the model itself could be defined as the expected maladaptive changes to arise from those impairments.

• Ankle/Foot
  • Medial tibial stress syndrome (24, 34, 44)
  • Pronation (30, 34, 44)
  • Ankle Sprain (Inversion sprain) (62, 75, 123-124, 195, 198 -199, 203 - 204, 207, 211-212)
  • Ankle instability (19, 34, 71 - 74, 126, 196-197, 200 -202, 205-206, 208-210, 213, 218)
  • Achilles tendinopathy (31, 34, 42, 44, 156, 159-167)
  • Tibialis posterior tendinopathy (36 - 39, 110, 115-117, 121
  • Plantar fasciitis (plantar heel pain,) (43, 69, 111, 153-158)
• Knee
  • Anterior cruciate ligament injury (16, 230, 234)
  • Functional valgus (16 - 18, 23, 26-29, 234)
  • Knee pain (patellofemoral pain syndrome, jumper's knee ) (46, 48 - 51, 53-54,56, 58-59, 93, 102, 170, 225, 234-236)
  • Lateral knee pain (iliotibial band syndrome, runner's knee) (172, 215-216)
  • Knee osteoarthritis (217, 224, 227, 228)
  • Knee effusion (100)
  • Proximal tibiofibular joint pathology (215-217)
  • Tibiofibular joint subluxation/dislocation (218-222)
  • Medial and lateral heel whip (45)
• Hip
  • Trigger points (84)
  • Abductor tendon tear (87)
  • Adductor Groin Strain (94 - 97)
  • Femoral acetabular impingement (FAI) (238)
  • Hip Osteoarthritis (83, 239)
• Lumbosacral
  • Low Back Pain (76, 78, 128-129)
  • Sacroiliac joint pain (77)