AVANTEON. Operative Technique & Catalogue Information AVANTEON

Transcription

1 AVANTEON Operative Technique & Catalogue Information AVANTEON H I P S Y S T E M

2 Pre-operative Planning The overall aim of pre-operative planning is to establish anatomical data from the patient to guide the surgeon towards the optimal size of the femoral stem and acetabular component and their ideal position after implantation. Anteroposterior and lateral X-rays with the hip in neutral position are overlaid with the template film for full pre-operative evaluation. PICTURE ARCHIVING AND COMMUNICATION SYSTEMS (PACS) templates are also available via your PACS software provider. The X-ray templates for the AVANTEON Hip system are set at 115% magnification. During pre-operative planning, the surgeon will normally establish the appropriate osteotomy level and estimate the femoral and acetabular implant size, allowing for adequate and continuous cement mantles. 1

3 Femoral Head Resection Resection cutouts Head centres Stem sizes Central axis of the stem The centre of rotation of the femoral head can also be established, which will help determine appropriate offset and neck length to achieve correct soft tissue tension and leg length.the appropriate level to make the femoral neck osteotomy can be identified using the osteotomy guide, and this should be used in conjunction with reference to the pre-operative templating. The AVANTEON osteotomy guide is placed over the exposed proximal femur and positioned so that the alignment guideline on the device aligns with the longitudinal femoral axis. The guide can then be moved along the longitudinal axis superiorly or inferiorly so that the centre of the femoral head matches the appropriate stem offset as determined by preoperative templating. AVANTEON H I P S Y S T E M 42

4 Acetabular Cup Implantation Acetabular Preparation The acetabular rim is fully exposed, identifying and removing all peripheral and medial osteophytes. Starting with the smallest reamer, the articular cartilage is progressiveley reamed until bleeding subchondral bone becomes visible. It is important not to over-ream the anterior and posterior walls. In order to achieve a 3mm thick cement mantle, the final implant is downsized by 6mm from the final reamer size used. Several holes are then made around the acetabulum using the acetabular step drill. These holes are created to aid keying and fixation of the bone cement. Care should be taken to place the holes where the bone is at its thickest and to avoid perforation medially and anteriorly where it is at its thinnest. 3

5 Acetabular Cup Insertion The rings on the flange are set 2mm apart. Present the cup to the prepared acetabulum to assess the amount of flange to remove, and trim the flange so that the periphery of the flange sits just inside the acetabular rim. The bone cement is mixed as per the manufacturer s instructions and guidelines. Pulsed lavage and drying of the bone bed are recommended prior to cementation. Bone cement is introduced into the acetabulum in the normal manner. An acetabular pressuriser should be used to intrude the bone cement into the prepared acetabular bony bed, ensuring good cement-bone interdigitation. (Bone cement and pressuriser are not supplied in the standard AVANTEON hip system). The acetabular cup is attached to the cup inserter by pressing the pins on the inserter into the holes on the inner rim of the cup. The acetabular cup is introduced once the bone cement has reached the stage when its viscosity is suitable. 64

6 Acetabular Cup Insertion 45 The acetabular cup is introducted so the shaft of the inserter is at 90 to the sagittal plane of the body. The cup will then be located with 45 of abduction. The acetabular cup pusher engages with the acetabular cup inserter, and pressure is applied to the cup directly in line with the cup face or 45 to the vertical of the acetabular inserter handle. The anteversion handle can be used to confirm the degree of anteversion relative to the coronal plane of the body. The degree of anteversion is at the discretion of the surgeon. Note: The pressure applied to the acetabular pusher should be in line with the anteversion handle. 5

7 Pressure is maintained on the acetabular cup with the AVANTEON cup pusher, which attaches onto the AVANTEON cup inserter. After satisfactory placement of the cup in the acetabulum and confirmation of correct alignment, the inserter is ejected from the cup by depressing the button on the end of the inserter. Once the inserter has been ejected, the acetabular cup pusher must be immediately reintroduced directly into the cup to maintain pressure on the cement. Any extruded bone cement is removed from the periphery of the cup, and pressure is removed until the bone cement is adequately polymerised. After polymerisation is complete, the acetabular cup pusher is removed. Any cement debris and further cement extrusions must be removed from around the cup. AVANTEON H I P S Y S T E M 86

8 Femoral Canal Preparation Note: Pre-operative planning and templating, by either PACS or hard-copy x-rays is essential when using a tapered, polished femoral stem to ensure correct leg length, soft tissue tension, and restoration of anatomy. Variations in patient anatomy mean that using the same anatomical reference points in the same way in every patient is inappropriate. Attach the box osteotome to the broach handle and open up the medullary canal by aligning the cut of the osteotome with the piriformis. The appropriate degree of anteversion should be determined at this point. In preparation for broaching and distal cement insertion, the femoral canal is enlarged using one or both of the straight reamers. The reamers are used sequentially, smallest first, to widen the femoral canal until the required diameter and depth are achieved while maintaining neutral axial alignment within the femur. It is recommended that there is a 1-2cm depth of cement between the distal tip of the stem centraliser and the top of the cement plug. Therefore, as a guide, the reamer should be introduced to a depth of 20cm measured to the tip of the greater trochanter. 7

9 Femoral Rasping The AVANTEON broaching system is designed to provide a uniform continuous cement mantle of at least 2mm. The medial cement mantle increases from 2mm at the distal tip of the stem to 4mm in the calcar region. 150mm Preoperative planning will enable the surgeon to identify the correct offset stem to use. The medial curve of the broach and the stem vary depending on the stem offset. It is essential to use the correct broach that corresponds to the stem offset determined in the preoperative planning. The smallest broach (CDH) is used first to prepare the proximal femur. Further broaches increasing in size sequentially are used until the broach corresponding to the templated stem size is reached. Maintaining neutral axial alignment within the medullary canal is essential. The anteversion rod may be attached to the broach handle to aid alignment and for additional guidance while broaching. 8

10 Trial Reduction Note: The CDH and 38mm offset stems use the same trial neck The two small holes and the flat on the rasp where the trial neck sits correspond to the three depth markings on the definitive stem. The rasp can be inserted to the desired depth as indicated preoperatively, taking note of the depth marking when rasping. The correct offset trial neck is attached to the spigot on the rasp. The trial neck must be seated properly on the rasp to ensure that the appropriate trial neck has been selected. The trial head with the neck length required to re-establish the femoral head centre as measured in pre-operative x-ray templating is selected. The hip is reduced, and joint stability, leg length, and range of motion are checked. Further adjustments can be made using different neck length trial heads. 9

11 Cement Plug Insertion Stem 10mm to 20mm cement gap Typical distal cement plug The JRI intramedullary cement plug system can be used in conjunction with the AVANTEON cemented hip system. The intramedullary cement plugs are available in a comprehensive range of sizes from 10mm to 20mm maximum diameter in 1mm increments. Made from UHMWPE, when sized and fitted correctly the plugs provide a secure barrier against the ingress of bone cement distally down the femoral canal, enabling pressurisation. The size of cement plug to be used should be determined by using the intramedullary trials to estimate the diameter of the femoral medullary canal at a depth 10-20mm beyond where the tip of the distal centraliser is intended to be. This is approximately 190mm - 200mm from the greater trochanter. As a guide, if only the small intramedullary reamer was used to start with, trial for the size 10mm cement plug initially. Trial for the 14mm cement plug if the large intramedullary reamer was used. Increase the size of the trial until resistance is felt at a depth of approximately 18cm from the greater trochanter. It is recommended that a cement plug 1mm greater than the trial is used to ensure a secure fit. AVANTEON H I P S Y S T E M 10

12 Stem Implantation In preparation for cementing, the medullary canal is cleared of debris and cleaned using pulsed lavage and then dried. The cement is then inserted using a cement gun and a retrograde filling technique until the canal is almost filled. A pressurisation seal is then added, before completion of filling of the canal, to enable optimum cement pressurisation. The optimum time for insertion of the femoral stem will depend upon the cement manufacturer s guidelines. (Bone cement, cement gun, and the femoral cement pressuriser are not supplied with the AVANTEON cemented hip system). A separately packed stem centraliser is attached to the distal tip of the stem. The distal tip of the introducer is inserted into the aperture on the lateral shoulder of the stem. 11

13 The pressurisation seal is removed, ensuring that the proximal cement is clean and dry. The femoral stem is inserted to the predetermined depth, referencing the depth indication markings on the stem while ensuring a neutral axial alignment of the stem is maintained. The depth to which the stem is inserted and the degree of anteversion are at the discretion of the surgeon. The stem is held in place with the stem introducer until the bone cement has polymerised. (Refer to the bone cement manufacturer s guidelines). The stem introducer is gently removed while applying counter pressure on the stem. It is recommended that a further trial reduction is performed with the trial femoral head at this stage. The neck of the stem should then be cleaned and dried before the definitive femoral head of choice is placed onto the taper and impacted. 12

14 The definitive femoral head with the desired neck length is placed carefully onto the clean taper of the femoral stem using a twisting motion. The definitive femoral head is impacted using the head impactor, with a single firm blow, ensuring the surface of the head is not scratched or damaged in any way. After ensuring that the cup and femoral head are clean and free from debris, the hip is reduced and closed. 13

15 AVANTEON and Furlong Compatibility Chart AVANTEON H I P S Y S T E M BIOLOX delta Cups AVANTEON Cup If using with CoCr Femoral Head, use ONLY AVANTEON CoCr Femoral Head. CSF, CSF Plus and Cemented Mueller type cup Hemiarthroplasty Heads Heads AVANTEON CoCr BIOLOX delta Furlong CoCr Bi-Polar Mono-Polar Stem AVANTEON H I P S Y S T E M AVANTEON H I P S Y S T E M 14

16 Implant Range Information CAT. NO STEM * CDH 36mm offset Size 0 38mm offset Size 1 38mm offset ISO Size 2 38mm offset Size 3 38mm offset Size 4 38mm offset Size 0 45mm offset Size 1 45mm offset Size 2 45mm offset Size 3 45mm offset Size 4 45mm offset * ATTENTION WARNING - AVANTEON cemented hip CDH stem has a weight limit of 56kg and must not be used with femoral heads of more than +4mm neck length Size 1 50mm offset Size 2 50mm offset Size 3 50mm offset DESCRIPTION CAT. NO Distal Centralizer with Tantulum bead Material Size 10-18mm PMMA DESCRIPTION CAT. NO DIAMETER Cement Plug mm mm mm mm mm mm mm mm mm mm mm 15

17 CAT. NO HEAD DIAMETER NECK LENGTH mm mm mm + 4 * mm + 8 * ATTENTION WARNING - AVANTEON cemented hip CDH has a weight limit of 56kg and must not be used with femoral heads of more than +4mm neck length. CAT. NO CUP SIZE STD 40mm STD 42mm STD 44mm STD 48mm STD 52mm Acetabular cups are available as Standard (STD) or Long Posterior Wall (LPW) STD 56mm STD 60mm LPW 40mm LPW 42mm LPW 44mm LPW 48mm LPW 52mm LPW 56mm LPW 60mm 16

18 Instrumentation DESCRIPTION CAT NO. 1 Osteotomy Guide Box Osteotome Small Large Acetabular Step Drill Acetabular Cup Inserter Acetabular Cup Pusher Anteversion Handle

19 DESCRIPTION 1 Intramedullary Reamer CAT NO. Small 10mm Large 14mm Broach CDH 36mm offset Size 0 38mm offset Size 1 38mm offset Size 2 38mm offset Size 3 38mm offset Size 4 38mm offset Size 0 45mm offset Size 1 45mm offset Size 2 45mm offset Size 3 45mm offset Size 4 45mm offset Size 1 50mm offset Size 2 50mm offset Size 3 50mm offset Broach Handle Trial Necks CDH and 38mm Offset mm offset mm offset Stem Inserter Femoral Head Impactor Trial Heads Neck Length 28mm - 3.5mm mm 0mm mm + 4mm mm + 8mm mm + 12mm AVANTEON H I P S Y S T E M 18

20 Mueller Cup Range DESCRIPTION PRODUCT NO. Cemented Acetabular Cup - UHMW polyethylene 28mm I/D 44mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D Cemented Acetabular Cup - UHMW polyethylene 32mm I/D 47mm O/D mm O/D mm O/D mm O/D mm O/D Cemented Acetabular Cup - CLP75 highly cross-linked UHMW polyethylene 36mm I/D 50mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D Furlong Hemiarthroplasty Heads 12/14 Taper DESCRIPTION PRODUCT NO. Bipolar Heads 40mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D Physiological Heads 39mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D mm O/D

21 Furlong THR Ceramic Femoral Head 12/14 Taper PRODUCT NUMBER HEAD DIAMETER NECK LENGTH c 28mm -4mm c 28mm 0mm c 28mm +4mm c 28mm +8mm c 32mm -4mm c 32mm 0mm c 32mm +4mm c 32mm +8mm c 36mm -4mm c 36mm 0mm c 36mm +4mm c 36mm +8mm c 40mm -4mm c 40mm 0mm c 40mm +4mm c 40mm +8mm Furlong THR CoCr Femoral Heads 12/14 Taper PRODUCT NUMBER HEAD DIAMETER NECK LENGTH mm -4mm mm 0mm mm +4mm mm +8mm mm +12mm mm +16mm mm -4mm mm 0mm mm +4mm mm +8mm mm +12mm mm +16mm mm -4mm mm 0mm mm +4mm mm +8mm mm +12mm mm +16mm 20

22 Polyethylene CLP75 Bearing Cup Range Standard Liners (I/D) Cup/Reamer size (O/D 44mm mm mm mm mm mm mm mm mm mm mm 32mm 36mm H-A.C. CSF Plus - Liner/ head size combination chart CLP75 Polyethylene Hooded Liners (I/D) 28mm 32mm 36mm

23 CSF Plus Ceramic Bearing Cup Range Cup/Reamer size (O/D 44mm mm mm mm mm mm mm mm mm mm mm 32mm 36mm 40mm H-A.C. CSF Plus - Liner/head size combination chart Biolox delta Ceramic AVANTEON H I P S Y S T E M 22

24 JRI Services/Education Nurse Training Factory Visits Basic, instructional, and advanced hip courses On demand loan sets In-service technical support Consignment stock audits Instrumentation checks and maintenance Digital PACS and hard-copy X-Ray templates JRI Orthopaedics is wholly owned by Orthopaedic Research UK Manufactured & Distributed by For further information and training resources visit 18 Churchill Way, 35A Business Park, Chapeltown, Sheffield S35 2PY T: F: W: AVANTEON/OPTEC/V1/06/2017