No Tendon Cutting —
Walking Out in 5 Days
A tendon-sparing approach to joint replacement surgery is letting patients at Wellton Hospital stand up four hours after the procedure and go home unaided on day five.
As South Korea's elderly population continues to grow, knee arthritis and hip pain have become increasingly common concerns for older adults. Knee arthritis not only causes significant pain but severely restricts mobility, dealing a serious blow to quality of life. Hip injuries — typically the result of a fall — force patients to remain bedridden for extended periods, often triggering medical complications such as sepsis, pneumonia, and heart failure that can prove fatal. It is for this reason that doctors routinely warn: "A hip fracture in an elderly patient is dangerous."
Against this backdrop, joint replacement surgery for both the knee and hip has grown substantially in recent years. Simplified procedures and lower costs have contributed to the surge in patients seeking this option.
Specializing exclusively in joint replacement since 2003 — over two decades of focused expertise. Dr. Song has performed more than 6,000 knee replacement surgeries and over 6,000 hip replacement surgeries.
The "1·4·5 Method"
Wellton Hospital is proud of what it calls the 1·4·5 Method — a system designed to compress surgery time, accelerate rehabilitation, and get patients home faster than conventional approaches allow.
The Secret: Leaving the Tendons Intact
The key to this remarkably swift recovery lies in a single principle: never cut the tendons.
Supporting the hip joint is a group of gluteal muscles that includes the piriformis — a critical core stabilizing muscle. The piriformis is the muscle that engages when a golfer's foot pushes into the ground during a swing, absorbing what biomechanists call "ground reaction force." Four tendons attach directly to this muscle.
In conventional hip replacement surgery, those tendons are cut to gain access to the joint capsule. After the artificial implant is placed, the severed tendons are reattached and sutured. Dr. Song takes a different approach: using specialized retractors to pull the tendons aside and work through the resulting window of visibility, leaving the tendons entirely intact.
Preserving the tendons maintains the function of the piriformis, which prevents dislocation — the femur slipping out of the socket. Sutured tendons also risk re-tearing if the knee is bent beyond 90 degrees, which complicates rehabilitation. By keeping the tendons whole, we eliminate that risk entirely and can begin rehab the very next day.
Rehabilitation on the Wattbike
Patients recovering from joint replacement surgery at Wellton Hospital use a specialist training tool called the Wattbike — a high-precision stationary cycling system. Dr. Song, a cycling enthusiast himself, was introduced to the device through a former national cycling team representative he met at a cycling academy.
Unlike a regular stationary bike, the Wattbike captures over 1,000 data points per second, displaying precise real-time rehabilitation metrics that help both therapist and patient track progress objectively. Starting from the second day after surgery, hip replacement patients at Wellton Hospital undergo a month of customized Wattbike-based rehabilitation under the guidance of a dedicated physical therapist.
Dr. Song explains the mechanics: "Patients with hip problems often have a shortened leg on the affected side, which causes limping. The limp then reduces activity, which weakens the surrounding muscles, which worsens the limp — a vicious cycle. Cycling lets the saddle carry the body's weight, taking the load off the knee while simultaneously strengthening the muscles around it. With cycling shoes clipped into the pedals, you're not just pushing down — you're also pulling back through the stroke. That trains both the front and back muscles of the leg in a balanced way."
Recovery Tips from Dr. Song
Post-Surgery Guidance for Joint Replacement Patients
- Don't fixate on how far the knee bends. Korean sitting culture leads many patients to judge surgical success by how deeply they can flex their knee. In the UK and US — where joint replacement has a longer history — aggressive bending exercises are actually discouraged. Reaching 90–100 degrees of flexion is sufficient for full daily functioning.
- Avoid positions that stress the joint. Squatting, lifting heavy objects, and descending stairs or slopes all place heavy loads on the artificial joint, accelerating wear. These movements should be minimized in daily life.
- Cycling is the best low-impact exercise. For those with knee discomfort or who find running or hiking difficult, cycling is Dr. Song's top recommendation for weight management without joint strain. "I've been cycling for three years myself — I lost weight and can now hike mountains that once felt impossible," he shares.
- Stretch to straighten, not just to bend. Dr. Song recommends a triangular wedge stretching device placed behind the heel to encourage full knee extension. The principle: correcting bow-leg (O-leg) alignment distributes body weight evenly across the inner and outer knee, reducing uneven loading.
A Legacy of Expertise
Dr. Song closes with a reflection on where the field is headed: "There are many excellent surgeons working on the knee. The hip, though, still has much room for development. My hope is to refine the techniques that give patients the most comfortable surgery and the fastest possible recovery — and to pass that knowledge on to the next generation of surgeons."
