OA of hip

Osteoarthritis is a complex, active, degenerative joint disease involving bone, cartilage, synovium, ligament, surrounding muscles and surrounding affected joint.

Or

Age related wear and tear of joints.

Commonly involved joints are hip and knee due to weight bearing activities.

Epidemiology

The prevalence of OA increases with age:

10% of adults aged 35-45 years

40% of adults of age 45-55 years

Over 80% and rising rapidly in older than 65 which is creating fear of gray tsunami.

Types

There are 2 types-

  • Primary OA- Occurs in old age, mainly in weight bearing joints(knee and hip).
  • Secondary OA- Occurs due to underlying primary disease, often many years later. Common at the hip joint.

Etiology-

Biomechanical insult to the cartilage and underlying bone, causing degeneration at a faster rate than repair.

Hip is commonly involved in the population with western living habits.

Relevant anatomy-

Fig- Anatomy of hip

Causes of secondary OA-

  • Avascular necrosis
  • Coxa vara
  • Alcoholism
  • Post-traumatic e.g., fracture of femoral neck
  • Chronic liver failure
  • Patient on steroids
  • Patient on dialysis
  • Sickle cell anaemia

Pathology

  • First change- increase in water content and depletion of proteoglycans from cartilage matrix.
  • Repeated weight bearing- cartilage fibrillation.
  • Gridding mechanism- cartilage gets abraded until the underlying bone is exposed.
  • Joint margin gets hypertrophic- osteophytes formation.
  • Synovial inflammation and thickening of capsule- deformity and stiffness of joint.

Clinical features-

  • Pain (earliest symptom)- Initially after exertion or by the end of the day but later as the condition worsens it is felt even during rest.
  • Crepitus- felt on passive joint movement.
  • Swelling- Joint is swollen due to synovitis.
  • Stiffness
  • Feeling of instability

Prognosis-

Milder cases have 3 possible outcomes, these are-

  1. 25% cases will improve or resolve
  2. 50% cases will remain unchanged
  3. 25% cases will worsen with time

Very little changes are seen in the first 3 years and then further worsening progress.

Fig- Stages of osteoarthritis

Differential diagnosis-

  • AVN hip
  • Tb of femur
  • Other arthritic conditions
  • Fracture
  • Tumours
  • Infection
  • Dislocation of hip joint
  • Perthes disease
  • Gout

Diagnosis-

On physical examination-

  • Prominent articular margins due to osteophytes.
  • Crepitus sound produced in passive movements
  • Painful restricted movements
  • Decreased range of motion
  • Gait deviation
  • Groin pain on passive abduction and adduction

On Radiological examination-

X-ray-

  • Joint space narrowing
  • Osteophytes at articular margin
  • Sclerosis (dense bone under the articular surface) and cyst in subchondral bone
Fig- X-Ray showing OA of hip

For further investigation-

  • CT scan
  • MRI
  • Bone scan

Measurement scales-

  • Western Ontario and McMaster(WOMAC) OA index is used for pain and physical function examination.
  • Lower extremity function scale(LEFS)
  • Patient specific functional scale(PSFC)
  • Six minute walk test
  • Visual analogue scale

Management-

Medical management-

Pain management- 

Long acting analgesics-

  • NSAIDS
  • Steroids ( hydrocortisone)

Chondroprotective agents-

  • Glucosamine
  • Chondroitin sulphate

Viscosupplementation-

  • Sodium Hylarunon

Counter irritants and liniments.

Surgical management-

  • Osteotomy
  • Total joint replacement
  • Joint debridement
  • Arthroscopy
  • Arthrodesis
  • Pauwel’s varus osteotomy in patients with coxa valga
  • McMurry’s displacement in patients with coxa vara

Physiotherapy management-

Depending upon the severity of the disease, management can be

  • Preventive/ delay occurrence of disease
  • Stall progress of disease
  • Rehabilitate with or without surgery (surgery prevention if possible)

There is no particular treatment of OA but some studies have shown the evidence of recovery by symptomatic treatment along with proper nutritional support, adequate rest and ideal growth conditions in patients receiving a combination of medical management along with physical therapy.

  1. Lifestyle modification-
  • Weight and obesity management
  • Activity modification
  1. Education-

It is important to break myths about the disease and its course so educating patients is not so improving, still a significantly important step.

  1. Pain relief-
  • In acute stage- 
  • ice packs
  • Ice massage
  • Intermittent traction(not suitable for every patient)
  • Deep heating modalities- Ultrasound, pulsed SWD, TENS etc.
  • Aquatic therapy
  1. Mobilisation-
  • Start with relaxed passive motion by a therapist carrying the total weight of the limb to avoid voluntary contractions of the muscles in spasm.
  • Progress to active assisted by the help of ped-o cycle, stationary bike, pulley, knee ratchets or manual assisted to build muscle control, prevent compensatory pelvic tilt due to stiffness of affected hip.
  • Maitland low grade mobilisation progressed to high grades for early mobilisation and pain relief as it reduces compressive forces and intracapsular pressure.
  • Once muscle control is achieved then the patient is made to move throughout range independently to build his confidence and improve range of motion.
  • After achieving required range, strengthened by resisted movements, isometrics, weight bearing and weight transfer.
  1. Exercise therapy-

It is the best possible and cost effective treatment in osteoarthritis hip and knee which has been proven many times in various research and studies.

Moderately strong doses of well prescribed and monitored exercise therapy protocol is beneficial and gives tremendous outcomes.

Hydrotherapy and pnf are also few of the best techniques for hip and knee osteoarthritis.

Few of the mandatory interventions are-

  • Side stepping
  • Forward-backward walking
  • Shuttle walking
  • Quadriceps drills
Fig- Quadriceps drills
  • Cat-camel
Fig- Cat- Camel exercise
  • Clamshell
Fig- Clamshell exercise
  • Hip swings
Fig- Hip swing
  • Wall supported squats
Fig- Wall supported squats
  • Donkey kicks
Fig- Donkey kicks
  • Bridging
  • SLR (supine prone and side lying)
  • Gentle self stretch of gluteal muscle and IT band.

6.Gait training-

Fig- Gait cycle

Walking on markings or walking in parallel-bar with a visual feedback mirror is required for gait training next to pre-gait training.

Patients can walk with a cane support depending upon age and condition of the patient.

Reference-

  • Mark Dutton ( Dutton’s orthopaedic )
  • Mohit Bhandari ( Evidence based orthopaedics)
  • David J. Magee and Robert C. Manske ( Orthopaedic physical assessment)
  • Jayant Joshi and Prakash Kotwal ( Orthopaedics and applied physiotherapy)
  • J. Maheshwari and Vikram A. Mhaskar ( Essential orthopaedics