Mr Derek Bennett

Mr. Bennett is a specialist in primary and revision hip and knee replacement surgery. He was the Irish pioneer of enhanced recovery joint replacement surgery and is a current board member of the European Board of Orthopaedic and Trauma Surgeons, representing Ireland at the European Hip Society. Additionally, he serves as the Irish representative on the European Accreditation Committee for Continuing Medical Education in orthopaedic surgery.

Mr. Bennett is the immediate past president of the Irish American Orthopaedic Society and a former chairman of the Irish AO Faculty. He founded and chaired the Orthopaedic Department at Mayo University Hospital and has also served as the Clinical Director of the Perioperative Division. He has been a member of the Council of the Irish Institute for Trauma and Orthopaedic Surgery.

He delivered the Sir John Charnley Memorial Lecture to the British Hip Society in 2024 and gave the Presidential Lecture to the Oxford University Girdlestone Society in 2022.

Mr. Bennett is the founder of Operation Walk Ireland, a charity that provides hip and knee replacement surgeries in Vietnam. He is also the Chairman of the Mayo Arthroplasty Conference, Ireland’s largest annual hip and knee replacement conference.

Education – MB, BCh, BAO, MCh, FRCS (Tr&Orth)

Specialties

Partial Knee Replacement, Rapid Recovery Hip Replacement, Rapid Recovery Knee Replacement, Revision Hip Replacement, Revision Knee Replacement, Medico-Legal Assessments

Rapid Recovery Programme

The Rapid Recovery Programme is designed to minimise pain and reduce the physiological impact of surgery on the patient. It involves administering pain management before the operation to control discomfort and minimising any physiological disruption after the procedure, allowing patients to mobilize as quickly as possible following joint replacement surgery.

Typically, patients are encouraged to get out of bed and walk about two hours after the procedure, which helps significantly shorten the average hospital stay.

Total Hip Replacement

The hip joint is one of the body’s largest weight bearing joints. It is a ball and socket type joint, formed where the head of the thigh bone (femur) joins the pelvis. In Total Hip Replacement surgery the damaged bone and cartilage is removed and replaced with prosthetic components. In the early stages of hip arthritis simple treatments such as pain relieving medications, weight loss or an exercise program may be of benefit. As the disease progresses more invasive treatments may be necessary. These may include a steroid injection into the hip joint. In order to guarantee that the injection has entered the hip joint, x-ray or ultrasound guidance is necessary. This procedure is generally carried out in a hospital setting. Total Hip Replacement Surgery If simple measures are ineffective you may want to discuss hip replacement surgery with your doctor. If the pain in your hip is preventing movement, disturbing sleep or impairing your ability to walk and do your daily activities then hip replacement may be suitable for you. At Mayo Medical Centre we have pioneered a Rapid Recovery process which will allow full weight bearing within a few hours of the surgery and independent walking with crutches on the same day. Most patients only require two or three days in hospital after modern Rapid Recovery hip surgery. The surgery is usually carried out under epidural anaesthesia but most patients will also choose to be asleep during the procedure. The hip is a ball and socket joint. During the surgery the ball at the top of the femur and the lining of the socket are removed and replaced with artificial components. The muscles, ligaments and skin are then replaced and repaired. A dissolvable suture is used so no stitches or clips ever need to be removed from the wound. A dressing is placed over the wound which is changed before the patient leaves the hospital and can be removed completely a week later. Rehabilitation post Total Hip Replacement The Rapid Recovery process minimizes post-operative pain and physiological disturbance and this allows patients to mobilize a few hours after their surgery. The patient is guided through their post-operative rehabilitation protocol by their physiotherapist. Although full weight bearing is allowed on the day of surgery, we recommend that patients protect the muscle repair by using crutches for 6 weeks after the operation. In order to avoid dislocation of the joint we advise patients to avoid high flexion movements of the hip for 12 weeks after the surgery. By 12 weeks after the surgery there are no restrictions at all on the patient’s activity level.

The Knee Joint and Total Knee Replacement Surgery

The knee is the largest joint in the human body, a hinge-type joint made up of a complex network of bones, ligaments, muscles, tendons, and cartilage that work together to allow flexibility and function. The knee joint consists of three bones: the femur (thighbone), the tibia (shinbone), and the patella (kneecap). The patella is attached to the muscles, allowing you to straighten your knee. The ends of these bones are covered in cartilage, a smooth substance that protects the bones and enables easy movement. Ligaments along the sides and back of the knee hold the bones in place, working with muscles and tendons to enable you to bend and straighten your knee. Bursae, fluid-filled sacs, cushion areas where skin or tendons glide over bone. The synovium, the lining of the knee, secretes synovial fluid, which lubricates the joint and reduces friction during movement.

Anatomy of the Knee Joint

The knee is the largest and one of the most complex joints in the human body. Acting like a hinge, it allows bending, straightening, and slight rotation—essential for walking, climbing stairs, sitting, and standing.
Key Components Include:

• Bones:
• Femur (thighbone)
• Tibia (shinbone)
• Patella (kneecap)
• Cartilage: Smooth tissue that allows gliding movement and absorbs shock.
• Ligaments:
• Medial & lateral: Support sides
• ACL & PCL: Control front-to-back motion
• Tendons & Muscles: Connect bones to muscles like the quadriceps and hamstrings.
• Bursae: Fluid-filled sacs that reduce friction.
• Synovium: Produces lubricating synovial fluid.

Common Causes of Knee Pain

One of the leading causes is osteoarthritis (OA), a degenerative condition involving the gradual breakdown of cartilage, leading to:

• Pain and swelling
• Stiffness
• Decreased mobility

Risk Factors for OA:

• Age-related wear and tear
• Obesity
• Past knee injuries
• Genetic predisposition

Early Management of Knee Osteoarthritis

Non-surgical treatments may slow progression and relieve symptoms:

Conservative Options:

• NSAIDs or pain relief medications
• Weight loss
• Low-impact exercises (e.g., cycling, swimming)

Advanced Treatment: Injection Therapy
Hyaluronic Acid Injections:

• Typically administered in a series of three, one week apart
• Aim to supplement joint lubrication
• No activity restrictions post-treatment for most patients

Hyaluronic Acid Injection

What It Is:

• Sterile solution of sodium hyaluronate, naturally found in joint fluid

How It Works:

• Lubricates and cushions the knee
• Reduces friction and stiffness
• May relieve pain for several months

Administration:

• Injections are administered either by MR. Bennett or a qualified member of his team, ensuring safe, effective, and timely pain relief as part of a comprehensive treatment plan.
• Quick, mild discomfort only

Post-Injection:

• Follow rest and icing instructions
• Monitor for unusual symptoms

Not a cure — it’s a symptom-management option

Cortisone (Steroid Injections)

What It Is:

• Corticosteroid injection that mimics natural cortisol
• Temporarily reduces inflammation in joints or soft tissue

Used For:

• Arthritis
• Tendinitis or bursitis
• Carpal tunnel
• Tennis elbow
• Trigger finger

What To Expect:

• Injections are administered either by MR. Bennett or a highly qualified member of his team, ensuring safe, effective, and timely pain relief as part of a comprehensive, personalised treatment plan.
• May use local anesthetic
• Relief in a few days to 1 week
• Results may last weeks to months

Side Effects:

• Temporary pain or swelling
• Increased blood sugar
• Bruising, skin thinning
• Rarely: infection, blood pressure rise, or bone weakening

Limitations:

• Usually limited to 3 shots/year
• Avoid if you have infection, are on blood thinners, or have poorly controlled diabetes

Call your doctor if:

• Pain worsens
• You have fever or signs of infection
• No relief after 10 days

Total Knee Replacement Surgery

If conservative treatments are ineffective and knee pain interferes with movement, sleep, or daily activities, knee replacement surgery may be an option. At Mayo Medical Centre, we have pioneered a Rapid Recovery process that allows patients to bear full weight within hours of surgery and walk independently with crutches on the same day. Most patients typically only require 2-3 days in the hospital after modern Rapid Recovery knee surgery.
The procedure is usually performed under epidural anaesthesia, though most patients choose to be asleep during the operation. During surgery, the knee joint is opened, and the surfaces of the lower femur (thighbone) and the tibia (shinbone) are removed and replaced with artificial metal and plastic components. The Rapid Recovery process at Mayo Medical Centre ensures that patients can bear weight almost immediately and many can achieve a 90-degree bend in their knee within hours of the procedure.

Pre-Surgical Preparation: Key Areas

1. Diet & Nutrition

• Eat a balanced, nutritious diet in the weeks leading up to surgery.
• Proper nutrition helps support wound healing, tissue repair, and immune response.

2. Smoking Cessation

• Smoking increases the risk of anesthesia-related complications and delays healing.
• Quitting even 1 week before surgery can significantly improve recovery.
• Ask your care team for help with quitting.

3. Blood Clot Prevention

• Surgery increases the risk of DVT or pulmonary embolism.
• You may receive compression stockings, blood-thinning medications, and guidance on early post-op mobility.

4. Infection Prevention

Tell your care team before surgery if you have:

• Chest or urinary tract infections
• Skin issues near the knee (e.g., eczema, ulcers, psoriasis)
• A history of MRSA, VRE, or contact with infected individuals

5. Exercise & Physical Conditioning

• Stronger muscles leads faster recovery.
• A personalised physiotherapy programme will help:
• Strengthen muscles
• Improve flexibility
• Boost cardiovascular fitness

What to Expect After Joint Replacement Surgery

What It Can Do:

• Over 90% of patients experience improved mobility and pain relief

Realistic Expectations:

• May not fully restore natural knee motion
• High-impact activities (e.g., running, contact sports) are discouraged
• Kneeling or crouching may remain difficult

Recovery Timeline & Healing

• Initial swelling/bruising: May last up to 3 months
• Recovery progress over 12 months:
• Pain reduction
• Increased strength and stability
• Greater confidence in movement

Spine Assessment & Physiotherapy Support

At The Mayo Medical Centre, we have a dedicated Spine Assessment Clinic and a specialist physiotherapist available to support your recovery. This service is designed to help ensure a safe, effective, and speedy rehabilitation following your operation, with personalised guidance every step of the way.
Post-Operative Wound Care at The Mayo Medical Centre

If you have any concerns about your wound following surgery, please contact us immediately. It is important that you do not start antibiotics unless advised by MR. Bennett or a member of his team, as this can affect your treatment and recovery plan.

• 2 Weeks: Wound check with nurse
• 6 Weeks: X-ray and clinical assessment
• 6 Months: Functional evaluation
• 2 Years & Beyond: Long-term follow-ups every 5 years

Complex and Revision Joint Replacement Surgery

When hip or knee replacements fail or develop complications such as loosening, bearing wear, infection, or recurrent dislocation, patients are often referred to a specialist in hip and knee reconstruction, such as Mr. Bennett. With extensive experience in treating complex hip and knee issues, Mr. Bennett has lectured widely both in Ireland and internationally on this subject.
When a hip or knee replacement implant becomes problematic, the first step is to identify the root cause of the issue. Once this is determined, a treatment plan can be developed. This often involves further surgery to remove and replace an implant that is not functioning properly.
Although revision surgeries are more extensive than primary joint replacements, they are also performed using the Rapid Recovery process, which minimizes pain and physiological disturbance for the patient. The principles of preserving bone and minimizing injury to the muscles and ligaments around the joint are followed. Depending on the underlying cause of the issue with the implant, revision surgery may take 2-5 times longer than a primary hip or knee replacement. Consequently, the length of stay in the hospital is typically longer than with primary joint replacement surgeries.

Self-Pay Injection Packages

MR. Bennett offers self-pay packages for hyaluronic acid and cortisone injections, with prices starting from €200.00. This option is ideal for patients without health insurance who wish to access expert care quickly and affordably.

For further details or to arrange a consultation, please contact Helen at 094 90 20202 (ext. 3) or email [email protected].

Knee Replacement Surgery Options

Overview

MR. Bennett has extensive experience in primary knee and revision knee arthroplasty, treating a range of conditions including osteoarthritis, rheumatoid arthritis, and joint damage resulting from trauma. He utilises high-performance prosthetic implants alongside evidence-based surgical techniques to maximise mobility, reduce pain, and support long-term joint function. His patient-focused approach is designed to achieve optimal outcomes and restore quality of life.

When Is Knee Surgery Recommended

Surgery is usually advised when conservative treatments fail.

Common Indications:

• Persistent severe pain or swelling
• Limited mobility or daily activity challenges
• Pain interfering with sleep
• Difficulty working or socialising

Partial Knee Replacement (PKR)

• For: Damage in a single knee compartment (often inner side)
• Procedure: Replaces only the damaged portion
• Benefits:
• Smaller incision
• Preserves healthy bone & ligaments
• Faster recovery, shorter hospital stay
• More natural movement
• Targeted pain relief
• Keeps the ACL intact

Total Knee Replacement (TKR)

• For: Damage or arthritis across the entire joint
• Procedure: Full resurfacing with metal and plastic components
• Benefits:
• Long-lasting pain relief (implants last 15–20 years)
• Improved mobility and function
• Relieve pain
• Restore function
• Improve mobility
• Enable return to daily activities

Revision Knee Replacement (RKR)

• For: Failed prior implants, instability, infection
• Procedure: replace a previously implanted knee prosthesis that has failed due to wear
• loosening, infection, instability, or mechanical issues
• Challenges: More technically demanding than primary knee surgery
• Wear of implant components
• Infection
• Persistent pain or instability
• Stiffness or swelling

• Benefits:
• Restore function,
• Relieves pain from a failed or worn knee implant
• Restores stability and function to the knee joint
• Corrects issues such as implant loosening, wear, or infection
• Improves mobility and walking ability
• Addresses joint stiffness or instability
• Corrects alignment or deformity in the knee
• Enhances quality of life and daily function
• Uses modern implant techniques for improved durability

Mr. Bennett offers self-pay packages for hip or knee surgery, with prices starting from just under €6,000. This option is ideal for patients without health insurance who wish to access expert care without delay.

For further details or to arrange a consultation, please contact Helen at 094 90 20202 (ext. 3) or email [email protected].