Stanbridge - T4 - TE2 - W3 - The Hip

Therapeutic Exercise II: The Hip

• The course covers important aspects of hip structure and function.
• Students will learn to implement therapeutic exercise programs to manage soft tissue and joint lesions in the hip, considering the stages of recovery following inflammatory insults.
• Post-operative hip programs for common surgical procedures will be discussed.
• The course includes exercise progressions to improve range of motion (ROM), muscle performance, and functional use of the hip and lower extremity.

Hip Anatomy and Arthrokinematics

• The pelvis consists of the ilium, ischium, and pubic bones, with the pubic symphysis as the anterior joint and sacroiliac joints posteriorly.
• The femur transmits forces through the hips, pelvis, and trunk, supporting the weight of the head, trunk, and upper extremities.
• The hip joint is a ball-and-socket, triaxial joint, reinforced by three ligaments: iliofemoral (Y ligament of Bigelow, strongest), pubofemoral, and ischiofemoral.
• The iliofemoral ligament limits hip extension and external rotation.
• The pubofemoral ligament limits hip extension and abduction.
• The ischiofemoral ligament limits hip extension and internal rotation.
• The acetabulum is a concave surface, faced laterally, anteriorly, and inferiorly. It's reinforced by the acetabular labrum and articular cartilage (horse-shoe shape, thicker laterally).
• The femoral head is convex and attaches to the femoral neck, projecting anteriorly, medially, and superiorly.
• In open-chain movements, the convex femoral head slides in the opposite direction of the physiological motion of the femur. (e.g., flexion with internal rotation causes a posterior glide of the femur).
• In the distal fixation of the lower extremity (CKC), the concave acetabulum moves on the convex femoral head, gliding in the same direction as the osteokinematic motion.
• The pelvis connects the hip and lumbar spine, influencing movements across all three structures.

Pelvic Positions

• An anterior pelvic tilt results from the ASIS moving anterior and inferior, closer to the anterior aspect of the femur, creating hip flexion and lumbar extension.
• A posterior pelvic tilt results from the PSIS moving posterior and inferior, closer to the femur’s posterior aspect, creating hip extension and lumbar flexion.
• Lateral pelvic tilt involves frontal plane motion, defined by the weight-bearing extremity's opposite side elevating the pelvis. Weight bearing side adducts the hip and the opposite side abducts.

Review Questions

• What do each ligament do in the pelvis, and what motions stress each ligament?
• What are the arthrokinematics of the hip joint in closed vs. open chain?

Articulating Surfaces

• The acetabulum and femur articulate to form the hip joint. The shape, curvature, and relative position of the surfaces affect hip motion.

Hip Ligaments

• The three primary hip ligaments, iliofemoral, pubofemoral, and ischiofemoral, function to limit excessive ranges of motion, thereby supporting and stabilizing the joint.

Functional Relationships

• Lumbopelvic Rhythm involves the combined movement of the lumbar spine and pelvis during trunk flexion, with the pelvis shifting posteriorly to maintain center of gravity over the base of support.
• Muscle activation during gait or weight-bearing activities determines the efficiency of hip, knee, and ankle function and posture.

Lower Extremity Closed Kinetic Chain (CKC) Biomechanics

• Hip flexion in CKC is controlled by gluteus maximus & hamstrings.
• Hip extension in CKC occurs through screw home mechanism – internal rotation of femur on the fixed tibia.
• Hip rotation in CKC involves medial rotation (IR) with the force through the tibia causing eversion of the calcaneus & pronation of the foot during weight bearing.
• Hip rotation in CKC involves lateral rotation (ER) with force through tibia causing inversion of the calcaneus & abduction & dorsiflexion of the talus during weight bearing.

The Hip and Gait

• The movement of the hip flexors, extensors, and abductors influence gait.

Pathomechanics

• Decreased flexibility at the hip leads to increased force transmission to the spine
• Adaptively shortened hip flexors; Excessive lumbar extension as hip extends; excessive load on the knee unable to lock the knee if the hip is flexed; compensation occurs with excessive trunk flexion.
• Adaptively shortened hip adductors may result in contralateral hip drop and ipsilateral side bending of the trunk.
• Decreased strength of hip abductors creates excessive trunk motion and stress on the lumbar spine (Trendelenburg sign or compensatory Trendelenburg Sign).

Therapeutic Exercise Intervention

• Specific exercises are presented to address shortened muscle groups.

Muscle Imbalances

• Dominance of hip flexors (rectus femoris, TFL, sartorius) over ilioposas causes faulty hip mechanisms or knee pain.
• Limited glute maximus flexibility leads to increased tension on the ITB & PFJ, or trochanteric bursitis.
• Dominance of hamstrings over glute max leads to cramping with hip extensor exercises; increased muscle imbalance at the knee (overuse syndromes).

Hip Fractures

• Common hip fractures include intertrochanteric fractures (most common), subtrochanteric fractures, and intracapsular fractures (femoral head, subcapital, and femoral neck) that may cause disruption of vasculature and/or damage to joint cartilage.
• ORIF is a treatment option for hip fractures typically involving a displaced, non-displaced intra-capsular femoral neck fractures, fracture-dislocations, stable/unstable intertrochanteric sub-trochanteric fractures.
• ORIF management focuses on tissue protection—soft tissue healing takes about 6 weeks and bone healing up to 16 weeks depending on fracture site.

Hip Osteoarthritis

• OA, RA, traumatic arthritis, AVN, ankylosing spondylitis, non-union of a fracture, joint instability or deformity, bone tumors, or failure of previous procedures are some possible causes.

Hip Surgery and Post-operative Management

• Total Hip Arthroplasty (THA) and Hemiarthroplasty are surgical options.
• THA types include cemented and un-cemented, with indications, surgical approaches, and complications.
• Minimal invasive techniques & procedures.
• The post-operative management phases (Maximum Protection Phase, Moderate Protection Phase, and Minimum Protection Phase) include activities, and criteria to progress between phases.
• Motion precautions vary depending on the surgical approach (posterior vs. anterior) to prevent complications like dislocation
• Maximum protection phase focuses on preventing vascular and/or pulmonary complications, preventing dislocation, and achieving independent functional mobility thru transfer, bed, and gait training.
• Moderate Protection phases emphasizes restoring and increasing range of motion (ROM), regain strength/endurance, improve balance/postural awareness, progress WB activity to tolerance.
• Minimum phases (12 wks post-op): Improve muscle performance/cardiovascular endurance. Reinforce patients' knowledge of activity restriction to lessen excessive demands on the hip joint.

Review Questions

• What is the capsular pattern of the hip?
• Name a stretch to address loss of each movement due to the capsular pattern.
• What are some common exercises to activate glute max and glute med?