Hip Anatomy and Ligaments

• Hip Notes Module date 2025-03-23 for Ortho Tx FT400 PT at 5:17 PM.

Anatomy

• The acetabulum is formed by portions of all three bones.
• The acetabulum includes the lunate surface, acetabular fossa, and labrum.
• Acetabular labra increase joint coaptation force.
• Clinically relevant bursae are the iliopectineal, trochanteric, and ischial/ischiogluteal.
• Anterior hip bursae include iliopsoas.
• Trochanteric bursae are located at the greater trochanter of the femur.
• Glute med, glute min, piriformis, obturator internus, superior gemellus, and inferior gemellus attach to the trochanter.
• The glute max tendon passes over the top of the bursae posterolaterally.
• The femoral triangle is formed by the inguinal ligament superiorly, adductor longus medially, and sartorius laterally.
• The femoral triangle contains the femoral artery, nerve, and lymph glands.

Ligaments

• Iliofemoral ligament prevents excessive extension and internal rotation.
• Ischiofemoral ligament prevents extension and internal rotation.
• Pubofemoral ligament prevents abduction and internal rotation.
• The iliofemoral ligament is the strongest in the human body.
• Ligamentum teres makes no contribution to stability (minor adduction).
• Transverse acetabular ligament makes no contribution to stability.

Resting Position

• Three degrees of freedom: Flexion/Extension and Rotation.
• Femoral head is convex, acetabulum is concave.

Close-Packed Position

• Slight extension, abduction, and internal rotation.
• Flex AB IR > Ext-AD-ER

Capsular Pattern

• ER-50°: F-1-35°1 AB-25°IR

Accessories

• Assists joint nutrition by facilitating blood and synovial fluid flow.
• Forms foramen for acetabular artery.

MMT Review

• Hamstrings, Quads group, Rec Fem, Psoas major, Sartorius, TFL.
• Adductor group, Glute med, Glute min, Glute max.
• Internal rotators group, External rotators group.

Biomechanics

• Angle of Inclination is measured in the frontal plane, between the femoral neck and shaft (normal adult is 125 degrees, child is 150 degrees).
• Decreased angle is Coxa vara and leads to genu valgum.
• Increased angle is Coxa valga and leads to genu varum.
• Coxa vara is less common than coxa valga.
• Anteversion is measured in the transverse plane between head/neck axis and transcondylar axis of the femur (normal is 8-15 degrees).
• Excessive Anteversion ranges from 15-30 degrees and creates a positional change causing apparent excess medial rotation and decreased external rotation.
• Retroversion ranges from 5-8 degrees and creates a positional change with a backward lateral orientation of the femur.
• Anteversion is assessed with Craig's test (Ryder's sign).
• Excess anteversion can lead to compensatory toe-out or non-compensatory toe-in gait.
• Compensatory gait is trying to keep the foot forward.
• Retroverted hip would have apparent excess external rotation and decreased medial rotation.
• Retroverted hip can lead to unnatural compensatory toe-in or natural non-compensatory toe-out gait.
• Angle of Declination (Torsion) is measured in the transverse plane (normal is 15 degrees).
• Increased angle of declination to 30 degrees is antetorsion (medial twist).
• Decreased angle of declination to 5 degrees is retrotorsion (lateral twist).

Intrinsic Stability contributing factors are

• The acetabulum and labrum.
• Coaptation force creating 25kg of pressure.
• Strong ligaments.
• Dislocation requires a force in the medial direction.
• Dislocation is difficult in a closed pack position (Extension, Abduction, Internal rotation).
• Position of most vulnerability & dislocation is Flexion, Abduction & Internal rotation
• Abduction and internal rotation: poor congruency of joint surfaces
• Dashboard injury (MVA).

Weight bearing forces on the hip

• Two legs - receives force equivalent to half the weight of the upper body.
• One leg - each femoral head supports 3 times the weight of the body.
• The Centre of Mass is midline whereas the femoral heads are lateral.
• This creates a rotary force.
• Strong abductor muscles are needed to counteract this rotary force.
• With abductor weakness, the stance leg dips into adduction.
• Glute med, glute min, TFL are abductors primarily responsible for single leg stance strength.
• Pelvis drops due to weak abductors results in noticeable drop to the opposite side.
• The torso will lurch forward toward the side of weakness.
• Using a cane held in the hand of the unaffected side.
• High prevalence of OA at the hip.
• In normal stance, the acetabulum and femoral head are both oriented anteriorly.
• Posterior aspect of the femoral head is weight bearing and the anterior aspect is not.
• The anterior aspect is effectively undernourished leading to degeneration and arthritis.

Assessment

• Location of true hip joint pain is groin area.
• The lumbopelvichip complex suggests that the hip, pelvis and lumbar Spine Function together Clinically.
• Asymmetry at the AF joint indicates a possible hip issue.
• If trochanters are level, but there is asymmetry at the ASIS, PSIS.
• High side may have coxa valga or long femoral neck.
• Low side may have coxa vara, short femoral neck, cartilaginous narrowing from hip joint degeneration.
• Nelaton's Line a line is drawn from ASIS to same side isch tuber.
• A positive finding is that the trochanter is palpated well above the line.

Pathologies

• Strains.
• Sudden onset/clear MO.
• Either overstretched, overloaded, or heavy eccentric contraction.
• Most commonly at musculotendinous junction the muscle belly.
• Aggravated by lengthening, contracting against resistance, or palpation.

Observation

• Sharp and swelling if it's an acute strain.
• Swelling has gone down if its a late subacute strain.
• Function has improved since the injury if its a chronic strain.

Palpation

• Red/blue/purple bruising if it's an acute strain.
• Yellow/green/brown bruising if it's a late-subacute strain.
• No bruising & back to normal if its a chronic strain.

Movement

• Motion/ROM is limited an painful throughout with acute strain.
• Painful only at end-range of movement POP if it's a Late-Subacute strain.
• Possible to have pain with tissue stress if its a chronic strain.
• Hip flexor strain typically occurs proximal or mid-belly.
• A common quad problem involves two joint action sprinting, kicking, and jumping.
• Assess the adductor longus from cutting movements or sudden loss of balance.
• Groin Strain is a lay person's term for medial anterior thigh pain which has origin from lumbar.

Iliotibial Band & TFL Injuries

• ITB Sprain has Localised pain around greater trochanter which is normally from a fall or blunt impact.
• ITB Fasciitis has Diffuse pain around lateral thigh due to overuse of TFL.
• ITB Friction Syndrome involves diffuse radiating pain through the thigh.

Tendonitis (Tendinopathy):

• Difference is the MOI.
• If tendon thickens.
• Joint involvement is bursitis-tendon pathology.

Bursitis

• Trochanteric bursitis has Painful to touch and is aggravated by eccentric load.
• Iliopectineal bursitis has Palpable pain deep in the groin because of overuse of iliopsoas, especially when trying to flex against resistance.
• Ischiogluteal bursitis is superficial to bursa.
• Fractures has high risk of avascular necrosis following hip fracture due to compromised circumflex arteries

Fracture of the:

• Femoral head and joint capsule will occlude.
• Femoral neck (subcapital or intracapsular fracture) has high risk of non-union.

Joint Pathologies:

• Osteoarthritis (Degenerative arthritis) is common at the hip which erodes or creates pain
• Primary is idiopathic (aging).
• Secondary follows trauma.
• Mobility is lost to osteoarthritis
• In normal stance, the acetabulum and femoral head are both oriented anteriorly while both head
• Signs & Symptoms are Insidious onset and AM stiffness.
• Painful with prolonged use and relieved by rest while pain is deep in the groin area.
• Stiffness becomes worse over time while capsular pattern of restriction.
• Total Hip Arthroplasty (replacement) is very common.
• Very High rate of dislocation or injury post surgery and it's vulnerable to dislocation for 12 weeks post surgery.
• Avoid Flexion past 90, Adduction past neutral as well as avoid lying on the operated side.
• Classic is DashbBoard injury.

Types of Femoroacetabular Impingement (FAI):

• Cam-type involving abnormal bone morphology, which causes abnormal contact.
• Pincer-type abnormal acetabulum.
• Combined-both femoral neck and acetabulum.
• Diagnosis of Fall is symptomatic hip and x-ray findings.

Capsular Sprains

• Limited to mostly flexion and internal rotation and is created by twisting or impact.

Piriformis syndrome

• Review your PNS Tx.

Orthopedic Tests

• Craig's test is used when there is internal rotation.
• Hip scour test is done when the patient feels Hip/joint pathology and tests that the hip can internally rotate
• FABER test is done to confirm Hip Joint pathology.
• FADIR test tests hip joint pathology or acetabulum.
• Ober's test tests the ITB or TFL to search for shortness in TFL or decreased hip extension.

Home Care

• Principles include not causing pain and start as early as possible but also strengthen the glutes.

Program Selection

• Loaded exercises can be Performed in mid-range, isometrics before and bilateral.
• Gravity is removed exercises like clamshells.
• Discomfort post exercise occurs for more than 2 hours in acute subacute stage.
• Hip OA or joint pathology exercises are supine with band above knee, Short lunges for load acceptance in quads as well as Sit to stand out of chair
• Supine with
• Sit in rocking chair.
• Hip circles, pelvic rocking while the common stretch is for Glutes, quads as well as adductors.
• Glute strengthening:
• Clamshells are the best glute isolation exercise.
• Fire hydrant also good, but challenging and harder to progress.
• Bridges are good general strengthening for hamshings
• Two-legged squats.
• Crab walking with band above knee