Hip osteoarthritis

Osteoarthritis of the hip is a degenerative condition of the hip joint, which progressively leads to loss of articular cartilage of the femoral head and acetabulum.

Osteoarthritis is the most frequent form of arthritis concerning millions of individuals worldwide. Often osteoarthritis of the hip involves other joints of the body including the knee, spine, hands and fingers. Hip osteoarthritis is a pathology resulting from the erosion of the joint due to ongoing destruction of the cartilage surrounding the bones (femoral head and acetabulum) with consequent joint deformity. The condition is generally progressive and becomes problematic in the population over 50s years. Women are generally more frequently affected than men. Hip osteoarthritis can arise following a traumatic event that alters the alignment of the hip eventually causing wear and tear of the joint. Ongoing local inflammation may also stimulate the growth of bone spurs. When the cartilage is worn out or injured, the hip fails to absorb impact during movement triggering pain and reducing mobility. Occasionally, hereditary factors may predispose to osteoarthritis of the hip.

Primary osteoarthritis is a global condition affecting joints of the hand, fingers, spine, hips and knees.Secondary osteoarthritis results from a traumatic injury, overuse, chronic inflammation and medical conditions that alter the composition of the joint cartilage (e.g. haemochromatosis). ;

The causes underlying hip osteoarthritis are not known. Some factors have been identified as a possible origin of the pathology:Overuse and repetitive stress to the hip in strenuous physical work and sportTraumaPrevious hip fractureCongenital malformation of the hipGenetic predisposition to osteoarthritis

The risk factors for a hip osteoarthritis include:Age > 50 yearsFemale genderObesity due to stress to the hip jointsHip injuriesCartilage abnormalities Chronic medical and inflammatory conditions (diabetes, rheumatoid arthritis, gout)Lack of physical training (muscle weakness)Race (Asian population and African Americans less prone)

In hip osteoarthritis, the clinical symptoms develop gradually with pain and stiffness building up and changing from sporadic to chronic. The main symptoms of this pathology are:Pain in the groin, thigh, buttocks, kneePain during or after movementTenderness at touchSwelling Stiffness of the hip joint particularly after inactivity (sleep, prolonged sitting) Reduced flexibility and range of movementLimpMalalignment of the jointGrating sensation during motionBone spur formation

The diagnosis of hip osteoarthritis begins with medical examination including the history of chronic conditions, past injuries and familiar predisposition. Radiologic evaluation with X-rays and MRI is used to establish the degree of cartilage damage, presence of spurs, changes in joint alignment and possibly avascular necrosis of the femoral head. Understanding the stage of joint degeneration will assist the orthopaedic surgeon in devising a suitable treatment, from conservative to surgery, relative to the patient age and general health.Laboratory blood tests are recommended to exclude chronic inflammatory autoimmune conditions (e.g. Rheumatoid arthritis). To ascertain the possibility of local infection to the hip or gout, the hip synovial fluid is drawn with a needle inserted in the joint for analysis.

As there is no cure for hip osteoarthritis, nonoperative therapy aims at reducing pain, improve movement and delay cartilage degeneration. Conservative management is recommended in the initial stages of the disease and consists of:Antiinflammatory therapy (NSAIDs)PainkillersGlucosamine and chondroitin sulphate (cartilage supplements)Local steroid injection (limited amount to prevent further cartilage degeneration)Physical rehabilitation

Surgical management of an osteoarthritic hip is necessary when the cartilage damage is so advanced to cause severe pain and limit ambulation. Different methods are available having gradually invasive interventions such as hip arthroscopy, osteotomy and prosthetic total hip replacement. ;Hip arthroscopy is used for various conditions of the degenerative hip in case of developed articular damage or osteoarthritic changes. Due to the small access to the hip with keyhole incisions, it is less invasive than open surgery and shortens the recovery period. An endoscope (camera) is placed through one incision while the surgical tool inserted through a second incision. The surgeon uses a monitor to visualise the area of interest during surgery. The procedure consists of rinsing the hip joint with a saline solution and removing fragments of cartilage that may be floating in the joint. This simple procedure brings a temporary relief of the symptoms.Osteotomy is performed when misalignment of the hip joint caused by an injury is the cause of arthritis. In order to reduce pressure between the articular bones, the surgeon resects part of the acetabulum and/or femoral head to establish a new anatomical relationship and reduce pressure. This method preserves the hip joint for longer and delays a prosthetic hip replacement.

Particularly in elderly people it is critical that immediately after surgery the patient begins rehabilitative therapy with gradual and assisted walking to prevent medical complications. This phase may require the patient to be admitted to a cared facility or receive regular in-home visits by an occupational therapist. A wheelchair, crutches, walking stick, or walker may be necessary to support the patient during the first weeks up to 12 months following a hip prosthesis. Rehabilitation during the first 6-12 weeks post surgery may also include:Ice/heat treatmentAntiinflammatory therapy (NSAIDs)Physical exercise to strengthen quadriceps, hamstrings and gluteal musclesHydrotherapyMassageJoint mobilisationGuided return to activityUse of high chairs and walking devicesWeight loss in overweighed patients

Hip osteoarthritis is not easily preventable, as the causes of the disease are not fully understood. There are however simple changes in life style can keep hip osteoarthritis under control and delay joint degeneration. These preventive measures include:Exercise and maintenance of muscular strength (walking, swimming) to support the hip and prevent cartilage damageMaintain a healthy weight Avoid injuries by reducing strenuous, repetitive physical activityStretch and warm up before exerciseAvoid running on hard surfaceUse of walking devices in the elderlyWearing suitable fitting shoesAdherence to occupational health and safety procedures for labourersFrequent monitoring of chronic inflammatory diseases and pharmacological use Improve nutrition with supplements (omega-3 fatty acids or fish oil, vitamins C and D)Treat pain with NSAIDs to reduce chronic inflammation Preventing the dislocation of a hip prosthesis To avoid displacement of hip prosthesis changes in the arrangement of furniture and in the bathroom may help preventing risky movements. This is achieved by elevating the furniture to avoid bending. The following rules, which depend on the surgical approach used, either anterior or posterior, will support the rehabilitative care post surgery. Anterior approach - avoid:Bending/stretching the hip backwards Turning or swing leg/foot outwardThe hip backward Walk with short stepsKneeling on one knee (use both) Place a pillow by the hip while lying on the backDon™t twist the body away from the operated hip ;Posterior approach - avoid:Crossing legs when in a sitting positionRolling leg and foot internally (use a cushion)Twisting upper body towards the hipBending hip over 90 degrees When standing up from seating swivel the upper body (do not bend)