Hip replacement surgery is a surgical procedure to remove the part of the original hip joint that is degenerated, dead bone, or fractured, and replace it with an artificial hip joint (Prosthesis) to allow movement that is as close to the movement of a real joint as possible.

Causes of Chronic Hip Pain

The common causes of chronic hip pain include avascular necrosis, osteoarthritis, rheumatoid arthritis, and degenerative disease from accidents.

• Avascular necrosis is a condition where the blood supply to the hip head is cut off, causing the hip head to collapse. It is commonly found in people aged about 30-40 years. Causes are often related to alcohol consumption, steroid medication, hip dislocation or fracture, and radiation therapy in the hip area.
• Osteoarthritis usually occurs in patients over the age of 50 and often with a family history of the disease. Sometimes it may be due to developmental stimulation leading to an uneven joint surface. When the uneven hip joint surfaces rub against each other, it causes hip pain and movement difficulties.
• Rheumatoid Arthritis is a disease that causes inflammation of the joint lining, leading to aseptic inflammation. It can happen in various joints throughout the body, with fluctuating inflammation causing joint surface damage. Patients often have multiple joint symptoms, commonly in the finger joints and have had inflammatory symptoms for a long time.
• Traumatic Arthritis occurs following an injury or broken bone around the hip joint which may destroy the joint surface or cause avascular necrosis, eventually leading to hip arthritis.
• Femoral neck fracture can occur in all age groups but is more common in the elderly, especially in those with osteoporosis who experience hip impact accidents.
• Congenital Hip diseases are degenerative conditions resulting from abnormal hip development in childhood, worsening with age.

When Hip Replacement Surgery is Needed

The decision to undergo surgery should be made jointly by the patient, the patient’s family, and the surgeon. Most patients who need hip replacement surgery are between 60 and 80 years old. The indications for surgery depend on the severity of the disease, pain, disability, and the patient’s overall health. The physician will evaluate the patient’s surgical indications and consider them on a case-by-case basis.

Indications for Hip Replacement Surgery

• Severe hip pain that limits everyday activities, such as walking or bending.
• Hip pain that occurs at rest, both during the day and at night.
• Stiffness in the hip joint that limits the ability to move or lift the leg.
• Inadequate pain relief from full-dose medication, along with physical therapy and the use of walking aids.
• Severe side effects from medications.
• Inappropriate bone fracture for treatment with metal fixation.

New Technique for Muscle-Sparing Hip Replacement Surgery

A new technique for hip replacement surgery that spares muscles, hides incisions, reduces scarring, causes less pain, recovers faster, and makes movement convenient (Direct Anterior Approach Cosmetic Incision Hip Replacement) or Direct Anterior Approach (Minimally Invasive) Total Hip Replacement has several advantages, including:

• Reduced pain.
• Faster recovery due to no muscle cutting.
• Smaller surgical scars.
• Surgeons can place the artificial hip joint more accurately than with traditional surgery.
• Low dislocation rate of the artificial hip joint.
• During surgery, special X-ray equipment can be used to ensure the artificial hip joint is correctly positioned.
• Use of Computer Navigation for precise placement of the artificial hip joint.
• Easy assessment of leg length after surgery for equal leg length.

Contraindications for Hip Replacement Surgery

1. Active infection with ongoing inflammation in the joint.
2. Patients with very weak hip muscles that could easily lead to dislocation of the hip.
3. Patients with neurological and muscle diseases that would affect the hip joint to be operated on.
4. Patients with blood or vascular diseases that have a high risk of complications.
5. Patients with severe osteoporosis in the hip area.
6. Extremely obese patients.

Components of the Artificial Hip Joint

The artificial hip joint has four main components:

1. The artificial hip socket made of metal, attached to the pelvic bone.
2. The socket surface made of special plastic that interfaces with the artificial hip head.
3. The artificial hip head made of metal, shaped similarly to the original hip head.
4. The artificial hip stem made of metal, anchored into the top part of the thigh bone.

Securing the Artificial Hip Joint to the Bone

There are two methods for securing the artificial hip joint to the bone, depending on the condition of the patient’s hip bone and the surgeon’s discretion:

1. Using a special cement for fixing bone to the prosthesis.
2. Securing the prosthesis to the bone without using cement, where the prosthesis has a rough surface that the bone will grow into.

Results of Hip Replacement Surgery

Most patients who undergo hip replacement surgery will experience significant reduction in hip pain and improvement in mobility and daily activities. However, hip replacement surgery cannot restore activities beyond what was possible before hip pain issues.

Lifespan of Artificial Hip Joint

The durability of the artificial hip joint varies among patients due to several factors, such as daily activities, weight, and surgical technique. Generally, artificial hip joints have an average lifespan of about 20 – 25 years if performed by experienced surgeons without complications.

Preparing for Hip Replacement Surgery

• Patient should be informed prior to surgery. Patients must be informed about the details of the prosthesis, the advantages, and benefits of the surgery, as well as possible disadvantages and complications.
• General health assessment is required once the patient decides to undergo hip replacement surgery, including detailed physical examination and health check-up to evaluate the body’s readiness before surgery.
• Laboratory tests will be conducted, such as blood tests, urine tests, chest X-ray, electrocardiogram, and other necessary exams.
• Preparation of surgical site involves ensuring the skin area to be operated on is free from infection or inflammation. If there is such a condition, inform the doctor before surgery.
• Blood donation might be required as surgeries could lead to blood loss. Some patients with high red blood cell percentage may choose to store their own blood for later use.
• Medications in use should be disclosed to the doctor to receive advice on which medications need to be stopped or can be continued until the day of surgery. Medicines and herbal supplements that affect blood clotting should be stopped at least 7 days before surgery.
• Weight reduction may be advised by the doctor for patients who are overweight to reduce the risk of complications during surgery.
• Dental and oral health assessment is necessary to ensure no infection in the mouth or teeth.
• Urine test is essential for patients with a history of urinary tract infections or men with prostate abnormalities to consult a urologist for evaluation before surgery.

Surgery and Postoperative Care for Hip Replacement

Day of Surgery

An anesthesiologist will take care of pain management and anesthesia. The surgeon will spend about 2 – 3 hours performing the surgery, opening the skin on the side of the hip, cutting the head of the thigh bone, preparing the bone cavity for the prosthesis, using trial components to select the appropriate size and test movement, followed by implanting the prosthesis with the stem in the thigh bone cavity, and attaching the prosthesis head to the stem. Afterward, the doctor will clean, place a drain, and close the incision. The patient will stay in the recovery room to monitor postoperative symptoms for about 2 hours before transferring to a special care room for one night and then to a regular patient room for another 4 – 5 days before being allowed to go home.

After Surgery

• The patient will wake up from surgery with various medical devices attached to the body.
• There may be symptoms of nausea or vomiting, side effects from anesthesia and pain medication.
• Cooperate and follow the instructions of the doctor and nurse caring for you post-surgery.
• Patients will be provided with adequate pain relief, but if the pain becomes unbearable, it’s important to inform the doctor or nurse immediately.
• Avoid postoperative pulmonary complications by taking deep breaths and coughing if there’s phlegm.
• To prevent dislocation of the new hip joint, post-operative positioning, such as using a pillow between the legs, is necessary.
• Most patients are trained to walk on the next day with the help of walking aids; early sitting, standing, and walking can aid in faster recovery and reduce the risk of complications.
• Physical therapists will teach the patient exercise programs to strengthen the hip joint and improve mobility.

Postoperative Complications

The rate of complications after hip replacement surgery is relatively low. The medical team follows treatment standards to prevent and reduce the risk of complications as much as possible. Possible complications include:

• Surgical site infection.
• Instability of the joint, prosthesis loosening or displacement.
• Bone fracture around the prosthesis.
• Damaged prosthesis, breakage, or calcification around the prosthesis.
• Pain in the operated area.
• Unequal leg length or abnormal leg alignment after surgery.
• Pathologies of blood vessels, nerves.
• Blood clot formation.
• Inadequate hip flexion.
• Complications from anesthesia, complications from pre-existing diseases.

Preparing for Postoperative Recovery

Once the patient is allowed to leave the hospital, they can walk using a cane or walking aids, but must be cautious in performing various routines. Adjusting the home environment can make life at home more convenient.

• Install grab bars in the bathroom and shower area.
• Install grab bars along corridors and stairs.
• Prepare a sturdy chair with armrests and a backrest. The chair should have an appropriate height, with knees slightly lower than the hips when seated.
• Prepare a raised toilet seat.
• Prepare a sturdy chair for bathing.
• Prepare soap on a rope and a handheld showerhead.
• Prepare a grabber to easily pick up items from low levels.
• Prepare equipment to assist with wearing shoes to avoid excessive bending of the hip.
• Rearrange objects to clear the pathways.
• Avoid getting the wound wet or damp.
• Eat easily digestible food high in fiber to prevent constipation.
• Exercise to improve movement and muscle strength as recommended by the doctor.
• During the first 2 – 3 weeks, patients still need to use a cane or walking aids while gradually increasing walking distance slowly.
• Some patients may feel numbness around the surgical incision or tightness, especially when bending the hip excessively, but these symptoms will improve over time.
• Patients may drive and exercise lightly after 4-6 weeks post-surgery, with the surgeon providing specific guidance for each patient.
• Generally, patients feel fully recovered 3 – 6 months after surgery.

Immediate Medical Attention for Abnormal Symptoms

• High fever, chills, or redness swelling around the surgical incision.
• Blood or pus seeping from the surgical incision.
• Increased hip pain during movement or at rest.

Precautions

To ensure smooth recovery and to prevent dislocation of the artificial hip joint, patients must:

• Avoid crossing legs.
• Use a pillow between legs when sleeping at night until the doctor permits discontinuation.
• Prevent falls by using a cane or walking aids until the hip joint is strong enough and moves well.
• Avoid bending the hip more than 90 degrees, such as sitting too low or picking items from the floor.
• Avoid twisting the foot excessively inward or outward.
• Avoid running or jumping as it may cause the joint to loosen or break.
• Avoid lifting heavy objects, pushing heavy things, and vigorous twisting movements.
• Avoid leaning while supporting weight, such as climbing steep hills or ladders.

Recommended Practices

• Regularly attend doctor’s appointments.
• Continue exercising and muscle strengthening around the joint as practiced in the hospital.
• Maintain appropriate weight, avoid obesity.
• Inform the dentist prior to dental procedures that you have an artificial hip joint to receive antibiotics beforehand.
• Patients should carry a card indicating the presence of metal prosthesis when passing through security devices, such as airports.

New hip replacement surgery techniques that spare muscle, hide scars with small incisions, reduce pain, recover quickly, and make movements convenient.