Distal Humerus 30mm surgical technique

Transcription

1 Distal Humerus 30mm surgical technique

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3 Distal Humerus 30mm surgical technique MUTARS was developed in co-operation with Prof. Dr. W. Winkelmann (former director) and Prof. Dr. G. Gosheger (director), Clinic and Polyclinic for General Orthopedics and Tumororthopedics at the University Hospital of Münster, Germany. MUTARS has been in successful clinical use since Table of Contents Table of Contents... 1 Information about the Silver Coating... 2 System overview... 3 Assembling options/reconstruction length... 4 Surgical technique... 5 Implants Instruments Nota Bene: The described surgical technique is the suggested treatment for the uncomplicated procedure. In the final analysis the preferred treatment is that which addresses the needs of the individual patient. Copyright note: MUTARS, implavit and implatan are registered trademarks of implantcast GmbH. The use and copy of the content of this brochure are only allowed with prior permit given by the implantcast GmbH.

4 The Silver coating Early and late infections represent the most severe complications of tumour arthroplastic treatments. Although local and systemic antibiotic treatments are considered, the scientific literature reports of infection rates from 5 to 35 percent. Reasons for these high rates are, for example, the long surgery time, the large incisions and the immunosupression due to chemo therapy and radio therapy as well as the increasing resistance of the bacteria against antibiotic drugs. The anti-infective effect of silver ions has been known for centuries i.e. the disinfection of potable water is based on this principle. This special property of silver is used for the silver coated components of MUTARS to build an intelligent protection against bacteria. Until now only non-articulating surfaces and surfaces without direct bony contact are coated with silver. In the catalogue information of this brochure you can find the supplement *S indicating which MUTARS components are available in a silver coated version. The eight digit REF number receives an addition after the last digit (e.g S). Important Application Instructions for the Use of Silver-Coated Components It is not permitted to flush the wound with antiseptics that contain Iodine or heavy metals (such as Betaisodona ). Iodine and Silver form insoluble salt complexes not only with the silver ions that are released post-operatively but also with the silver layer of the implant that will be covered with an insoluble silver-iodine (AgI) film. This will destroy the anti-adhesive protective layer irreversibly. Iodine or heavy metal based antiseptics may not be used at any time. Alternatively solutions containing H 2 O 2 (like Lavasept, Prontosan or similar) can be used. The silver coating can be destroyed in its function by two factors: large amounts of albumin from seroma or hematoma can bind larger amounts of silver (1 mol Albumin inactivates 3 moles Silver ions). This should be minimized by using an attachment tube. In the instance that an infection is known pre-operatively, antibiotics like Vancomycin can be mixed with the bone cement. The intramedullary stems are not silver coated and cemented components are preferred in case of a septic revision. The TiN coating for allergy prophylaxis As the metallic components of total knee replacements, the articulating metallic parts of the MUTARS system are made of casted CoCrMo alloy. In the late 70 s and 80 s of the last century, some of the Cobalt Chromium implants had a small Nickel content to add strength to the implant. Nickel is the primary cause for metal sensitivity, although some patients have shown to be hypersensitive to other metals such as Cobalt and Chromium. The use of titanium components can t solve this problem, because the wear of the articulating polyethylene inlays will increase and so the survival time of the prosthesis is reduced. Since the end of the 1990 s TiN (Titanium Nitride coating) has been successfully applied to protect the body against metal ions that could cause allergic reactions. The metal ion release of TiN coated or TiNbN coated implants is reduced down to 10%. 1 In order to prevent allergic reactions, certain parts of the prosthesis may be supplied with a ceramic coating (TiN). Since almost all components of the tumor system consist of titanium alloy, this only concerns those components, which are made of a cast CoCr alloy (CoCrMo). The REF-numbers of the TiN coated implants have the suffix N after the last digit (e.g N). *S: For anti-infective treatment, silver coated implants are available. *N: For anti-allergic treatment, TiN coated implants are available. 1 Metal Ion Release from Non-Coated and Ceramic Coated Femoral Knee Components: Boil test 240h in NaCl-solution nach FMZ PhysWerk VA 97350, University Würzburg (D) (On File) 2

5 System Overview 90mm or 120mm Agilon Trauma stem ø6, ø8, ø10 and ø12mm cemented length: 90 and 120mm humeral reconstruction length: 30mm Distal Humerus 30mm ulna anchorage cementless Ulna anchorage (TiAl 6 V 4 ) length: cementless 70mm (TiAl 6 V 4 ) cemented (CoCrMo) cemented (CoCrMo) length: 70mm and 100mm 3

6 MUTARS Distal Humerus 30mm assembling options (length in mm) Humeral components Reconstruction length Distal Humerus 30mm extension piece extension piece Screw for dist. Humerus 30mm ,5 30 7, , , , , Note: Please notice that the amount of implants and instruments send with an individual shipment may differ from the information in the catalogue information of this brochure. Please make sure, during the preoperatively planning, that all necessary implants and instruments are available for the surgery. 4

7 Tumor resection Measure the size of the resected amount of bone. Compare the length to the preoperative planning. Remark In the case that the radius head is free of tumor it needn t be resected. figure 1 The minimum bone resection is 30mm. Preparation of the proximal ulna Observe the bony geometry and fit of the ulna anchorage (fig. 1). Remove obsolete cartilage and bone from the olecranon (fig. 2). figure 2 Open the medullary cavity at the appropriate position by the use of the 6mm drill with stop (fig. 3). figure 3 5

8 Implantation of the ulna anchorage Insert the guide wire into the medullary canal. Use the flexible drill 5mm guided by the rod until the depth is reached. The cementless implants are available in length of 70mm, the cemented implants are available in the length of 70mm and 100mm. The example shows the correct depth for a 100mm long implant (fig. 4). To implant the ulna anchorage in the exact depth, the entry has to be extended ventral at the Proc. Coronoideus and dorsal. The olecranon should be preserved, if possible. figure 4 Rasp the medullary cavity with the MUTARS rasp for ulna anchorage (fig. 5 and 6). figure 5 Remark Risk of the via falsa with cortical perforation. Control in 2 plains under x- ray is recommended. figure 6 6

9 Ulna implantation and screw fixation of the ulna anchorage It is recommended to enhance the fixation of the ulna anchorage by adding a bone screw, both for the cementless and the cemented implantation. figure 7 If a cemented implantation is planned, clean the ulnar cavity and insert some cement. Insert and impact the ulna anchorage cemented or cementless. Use either the straight or the cranked setting instrument for impaction (fig. 7). Please follow the steps shown on the left. Drill with the 2mm drill, measure the length of the 4 mm screw (fig. 8) and insert the screw (fig. 9). Remark The use of a cancellous screw is preferable, because the use of a cortical screw can lead to a skin impigment. figure 8 Make again a concluding x-ray control in 2 plains and check the proper positioning of the implant as in example fig. 10 figure 9 figure 10 7

10 Humeral bone preparation Cementless use Drill the medullary cavity with a trauma stem drill (7-13 mm, in 1 mm steps) stepswise up to the planned diameter (1 mm bigger than preoperatively chosen stem) and the correct length (90 or 120 mm, see the mark on the drill) (fig. 11a). Please use additionally the tapered drill when a stem smaller than 12mm is planned used to complete the bone preparation (fig. 11b). Cementing of the assembled distalen Humerus 30mm It is recommended to insert a cement restrictor of cancellous bone taken from the bone chips found during bone preparation of the medullary cavity. figure 11a and 11b Assemble the stem of the correct size to the distal Humerus 30mm and lock the components with the screw of the correct length (see table 3, page 8) (fig. 12a). Fill the cavity with bone cement and insert the implant (fig. 12b). Remove remaining bone cement before cement hardening. Remark Alternatively the following technique may be used to implant the components. figure 12a and 12b 8

11 Cementing of the stem Mount the impactor sleeve and the impactor to the stem of the correct size. Fill in bone cement into the cavity. Insert the stem up to the correct depth (fig. 13a). Remove remaining bone cement before cement hardening. Make sure that the teeth mechanism of the components is free of bone cement. Remove the impactor and the impactor sleeve during cement hardening. Assembling of the distal Humerus 30mm Combine the distal Humerus 30mm and the distance sleeve occasionally with the stem. Insert the screw of the correct length and lock the components in the stem (see table 3) (fig. 13b). figure 13a and 13b Add. length Distance sleeve Screw 0mm none 15mm 5mm 5mm 15mm 7,5mm 7,5mm 20mm 10mm 10mm 20mm 12,5mm 5+7,5mm 25mm 15mm 5+10mm 25mm 17,5mm 7,5+10mm 30mm 20mm 10mm+10mm 30mm table 1 Use the hex driver 3,5mm to tighten the screw (fig. 14). figure 14 9

12 Trial reduction For trialing the cemented distale Humerus 30mm (fig. 15) and the previously implanted ulna anchorage will be combined (fig. 16). figure 15 figure 16 Interlock the joint components by inserting the trial axle (fig. 17a and 17b). Perform a trial range of motion test and stability test. Make sure that the correct rotational alignment is achieved. figure 17a figure 17b 10

13 Remove the trial axle after successful trial reduction. Add the counter screw and tighten it by the use of the small socket wrench (fig. 18a). Impact the ulna stop with the impaction instrument (fig. 18b) or a punch. The ulna stop has to be fully seated to achieve a full range of motion of the joint. figure 18a figure 18b Final reduction Connect the distal humerus 30mm to the ulna anchorage by inserting the articulating axle (fig. 19a). Locking of the hinge mechanism After coupling of the joint components (fig. 19b) please insert the locking screws on both sides in order to cover the articulating mechanism and to protect the axle Therefore the small socket wrench is used (fig. 20a and 20b). figure 19a figure 19b figure 20a figure 20b 11

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15 IMPLANTS *S: For anti-infective treatment, silver coated implants are available. *N: For anti-allergic treatment, TiN coated implants are available. Agilon Trauma stem cemented *N mat.: implavit ; CoCrMo-casting alloy according to DIN ISO 5832/ mm 6mm mm 8mm mm 10mm mm 12mm mm 6mm mm 8mm mm 10mm mm 12mm Agilon extension piece mat.: implatan ; TiAl 6 V 4 according to DIN ISO 5832/ mm mm mm MUTARS Distal humerus 30 mm incl. axle, safety screw and 2 lock screws mat.: implatan ; TiAl 6 V 4 according to DIN ISO 5832/3 axle CoCrMo-wrought alloy according to DIN ISO 5832/ Screw for dist. Humerus 30mm M6 mat.: implatan ; TiAl 6 V 4 according to DIN ISO 5832/ mm mm mm mm MUTARS ulna stop mat.: UHMWPE according to DIN ISO 5834/

16 IMPLANTS MUTARS ulna anchorage cementless mat.: implatan ; TiAl6V4 according to DIN ISO 5832/3 with cpti and HA-coating left 70mm right 70mm MUTARS ulna anchorage cemented *N mat.: implavit ; CoCrMo-casting alloy according to DIN ISO 5832/ left 70mm right 70mm left 100mm right 100mm cancellous bone screw 4mm mat.: implatan ; TiAl 6 V 4 according to DIN ISO 5832/ mm mm mm mm mm 13

17 INSTRUMENTS MUTARS Distal Humerus 30mm M6 instrument tray MUTARS Distal Humerus instrument tray left and right left right 14

18 INSTRUMENTS MUTARS rasp for ulna anchorage left right MUTARS instrument for ulna anchorage straight MUTARS instrument for ulna anchorage cranked MUTARS trial axle for distal humerus depth measuring instrument small drill 2 mm hexagon head screw driver 2,5 mm flexible drill 5 x 190 mm MUTARS 6mm-drill with stop

19 INSTRUMENTS AGILON guide rod AGILON traum shoulder reamer tapered AGILON trauma shoulder drill mm mm mm mm mm mm mm ic-t-handle A/O AGILON stem impactor AGILON impaction sleeve torque wrench 15Nm 5mm MUTARS socket wrench small MUTARS distal humerus 30mm trial

20 Your local distributor: implantcast GmbH Lüneburger Schanze 26 D Buxtehude Germany phone: fax: internet: MUTD6OPE *+E1ICMUTD6OPE++* *+$$E1IC *