For over 40 years, the LUBINUS SP II Hip System has held the distinction of being one of the most reliable cemented hip prosthesis systems.1 Its design and diverse sizes allow to provide the best possible cemented prosthesis for virtually every patient.1
The curved shape of the stem enables it to finds its way into the femoral canal, where it adapts perfectly to the anatomy.6 This means that stress peaks, as occur with three-point locking of straight shafts, are avoided and the stem has greater rotational stability.2
Developed in 1978, and available with a modular prosthesis head since 1984, this femoral stem was a great success and had a major influence on the principle of the anatomical hip prosthesis.1 The S‑shaped curvature, which follows the natural anatomy of the femur, has proved highly successful in this system. This has been repeatedly confirmed over the last 40 years in numerous publications, including the Swedish Hip Arthroplasty Register.1, 3 The outstanding clinical history was the reason for developing the SP-CL, based on the same principle.
The anatomical shape of the stem enables it to fit centrally in the medullary canal. This helps to ensure a uniform cement coating, which can envelop the implant optimally.7 At the same time, anteroposterior and mediolateral ribs contribute to rotational stability.2, 8, 9, 10
The SP II offers a system with great modularity. The multiplicity of possible variations in CCD angle, neck length, and stem length gives maximum flexibility for reconstruction of the anatomical structures in primary and revision arthroplasties. The stem tip is curved on the lateral side in order to prevent impacts when it is introduced into the medullary canal. The slender stem design meets all the requirements for minimally invasive, soft tissue, and bone-conserving implantation.
Many long-term outcomes with survival rates of up to 92.3 percent after 23 years emphasize the success and great reliability of the SP II Stem.1
* www.odep.org.uk; Orthopaedic Data Evaluation Panel
The SP-CL Hip Prosthesis System, with its anatomical, cementless design and its different versions, is aimed at the treatment of a wide range of patients. In order to meet the heavy demands put on the implants in a special way, the femoral components consistently follow the principle of the anatomical stem shape4, which has been in successful use for decades.
The anatomical S-shape helps to reduce stress peaks, which are a familiar problem with three-point fixation of straight stems. At the same time, it gives the implant greater rotational stability.1,5, 6
Metaphyseal fixation of the SP-CL is assisted by the HX coating (CaP).8 At the same time, the polished distal stem region protects against thigh pain.9,10 Medially the SP-CL rests along the length of the calcar (Shenton’s line) and is intended to promote a physiological distribution of forces.
The successful ribbed structure provides initial fixation in the compressed cancellous bone. This makes it possible to achieve a design elasticity in spite of the proven “fit and fill” principle in the proximal femur. Thus the ribs not only provide high primary stability,7 but in combination with the LINK Tilastan- S alloy, they also achieve double elasticity. This can lead to a reduction in “stress shielding”.1
Anatomically shaped stems necessitate anatomically shaped instruments. The compressors in the SP-CL System follow exactly the anatomical design of the stems and prepare the bone bed for the SP-CL stem according to the natural contours of the intramedullary canal in the proximal femur.
While the flat, lateral implant profile is designed to protect the greater trochanter during implantation, cancellous bone compressors help to preserve valuable bone substance during resection.11
The hip prosthesis stems of the LCU System follow the concept of a straight stem with tapered lateral shoulder and an osteoconductive coating.4 The straight profile with rectangular cross-section provides the implant with proximal stability. The HX coating promotes bone integration.1 Two types of stem are available for the purpose of adaptation to the patient’s anatomy2:
The following materials and coatings are used for the hip prosthesis stems of the LCU System:
A tapered distal end reduces distal bone contact and facilitates introduction of the stem into the medullary canal.1,5,6
The self-anchoring shape of the stem is an optimization of the standard design in the proximal region in order to promote mechanical stability and favorable load transmission to the bone surface. The horizontal ribs in the proximal section of the stem serve to counteract subsidence of the stem and to promote primary stability. The distal region has vertical ribs to counteract the rotational forces.7
Meta-diaphyseal support and fixation provided by a large medial curvature with a 100 mm radius of curvature for anatomical adaptation is the prerequisite for primary and secondary stability.
The primary stability of the implant is additionally enhanced by the characteristic metaphyseal V-shape, while the rectangular cross-section neutralizes torsion forces.1,5
The flat, tapering prosthesis neck allows a large scope of movement between prosthesis stem and acetabular cup.2 The 12/14 taper is designed for the use of modular LINK prosthesis heads made of ceramic or metal with various lengths and diameters.
Furthermore, the highly polished neck region reduces abrasion in the event of unintentional contact with the acetabular cup9.
The concept of double mobility was developed by Prof. Gilles Bousquet in 1975 with the aim of treating habitual hip luxation.13 The system consists of a metal casing with a highly polished internal surface and a movable polyethylene inlay, in which a press-fitted prosthesis head moves. This provides a greater range of motion with less abrasion14, 15, 16 and reduced risk of luxation.15, 17, 18 It was on the basis of this principle that the BiMobile Acetabular Cup System came about.
The development of the bimobile acetabular cup system drew on many years of experience with successful implant systems and fixation concepts plus state-of-the-art material and coating technologies. The result is the versatile BiMobile Acetabular Cup System.
The cementless BiMobile Acetabular Cup is available with a TiCaP double coating. The TiCaP double coating combines the properties of a highly porous layer of pure titanium for primary fixation and calcium phosphate coating, which together provide optimal primary and secondary implant stability.4, 5 A special macrostructure on the cup equator increases primary stability.9
The BiMobile Dual Mobility System is available in two versions, either cemented or cementless. The metal casings in both versions are fabricated from biocompatible, sturdy EndoDur CoCrMo material.1, 2 The inner surface is highly polished in order to minimize wear.
The cemented BiMobile Acetabular Cup has a finely matt-finished SatinLink surface, which is also a feature of the SP II stems. Latitudinal and longitudinal groove-like structures reinforce the fixation and allow air to escape when the implant is pressed into the cement bed.
The UHWMPE inlay can be combined with LINK prosthesis heads made of CoCrMo or ceramic with a 22 mm or 28 mm diameter.
The IP Polyethylene Acetabular Cup is a cemented acetabular cup made of UHMWPE. The direct stability of the cup in the cement coating permits rapid postoperative mobilization of the patient. This, in turn, means shorter recovery times and shorter hospitalization for the patient.1
LINK has decades of experience in the use of UHMWPE, and this was particularly valuable in the design of the cemented acetabular cups. The high quality of the polyethylene demonstrably minimizes abrasion suffered by the components, and thereby reduces the risk of osteolysis. Consequently, the incidence of component loosening is very low. 2, 3, 6, 7
In addition to the material properties, the external shape of the acetabular cups helps to prevent loosening. Radial notches in the surface create a high degree of cement contact and allow air to escape when the implant is pressed into the cement bed.4 Furthermore, spacers on the rear surface of the acetabular cup permit a uniform cement coating. This surface design increases the stability of the cup in the acetabulum, thereby largely eliminating the risk of loosening.8
Another feature of the cemented polyethylene acetabular cups is the high cup rim, which projects beyond the spherical shape. This gives the patient a wider range of mobility because the neck of the prosthesis strikes the cup rim later5. In combination with the Lubinus SP II Stem, this system offers an outstanding, anatomically adapted cemented hip implant.
The MP Reconstruction System gives the surgeon the intraoperative flexibility and certainty1 that is essential for a successful revision procedure with pronounced bone loss. The system’s unique design has produced outstanding outcomes for decades.2, 3, 4
With just three instrument trays, the MP System enables a simple and fast surgery and a smooth process in five steps. The modular system gives the surgeon a high degree of flexibility in terms of adapting leg length, offset, and anteversion, independently of the distal cementless anchoring of the stem. This permits a quick and uncomplicated intraoperative response to the individual anatomy and defect.5
The stems in all six lengths have a 3° angulation, which facilitates following the anatomical curvature of the femur. The 2° tapered stem with peripheral longitudinal ribs gives outstanding stability in the femur, even with large proximal defects.2
The PowerLock toothed connection allows the stem length to be adjusted intraoperatively by means of spacers in 10 mm increments up to 30 mm for revision arthroplasties. The absence of a taper connection means that the stem length and also the anteversion and offset can be adjusted retrospectively without endangering the distal fixation of the stem.