The present invention relates to a surgical instrument for avasclar necrosis of the femoral head (AVN) capable of improving the recovery of a patient after surgical operation by carrying out the implant without exhausting a hip joint bone of a patient.
The present invention relates to a modular FHSR, a modular femoral neck stem, and related sleeve, adapter and osteoconducting rod, which are used to perform total hip replacement.
Background and unmet needs
Many implants have been developed to treat intertrochanteric femoral fractures which are basically based on a hip nail or screw that is inserted from the side of the femur through the femoral neck and into the head. Afterwards it is fixed either to an intramedullary nail positioned inside the femoral shaft, or to a side plate.
Bone contact was insufficient to support a patient's weight, resulting in an increased risk of bending or breaking of the implanted hip nail. This, together with the shape of the hip nail, distributed too much pressure over the femoral neck and head bone tissue, causing the implant to cut through the cancellouse tissue of the femoral neck or head in a condition known as "cut out", causing the nail to pierce the surface of the femoral neck or head, or at the least to lose proper alignment of the bone fracture.
To solve one of these difficulties, collapsible implants were developed.
Discovery and Achievements
The total hip replacement, which is the final treatment method of osteoarthritis and AVN of the femoral head, is the most successful treatment to relieve pain, recover stability and increase the range of motion. However, as time goes, because of progressive wear of the plastic liner, osteolysis resulted in the pelvis and femur by abraded particles, causing a reduction in the range of motion of the hip joint and increased dislocation rate of the hip due to a small femoral head and instability.
Simple and fixed-type big femoral heads or FHSR are commonly used in the world medical market, but a modular femoral head surface replacement according to the present invention gives convenience and support to a surgeon to choose a straight or tapered, fluted type stem according to the patient's bone state.
Now is the time to challenge the market of medical appliances owing to development of the metal industry and ceramic technology. The most important factor for the surgeon in choosing the implant is the design.
The various types of FHSR or modular big femoral head can be selected according to the patients' conditions. The sleeves of various types can be applied according to the degree of AVN to prevent breakage of the femoral neck support femoral neck stem metal.