REFERENCES FEMORAL REINFORCEMENT. A unique combination of modular revision hip prosthesis with locking intramedullary nail

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1 REFERENCES 1. Cannulated interlocking titanium prosthesis in pathological proximal femoral fractures: a prospective study. Thayur R. Madhusudhan, Sanath Kumar Shetty, B. Ramesh, I.C. Smith. European Journal of Orthopaedic Surgery & Traumatology. 2009, Vol. 19, No. 5, Experiences with a distally locked femoral component in revision hip arthroplasty. H. Tanaka, A. Wakisaka, T. Taguchi. 8th Congress of EFORT, Florence, May The use of a hydroxyapatite coated distally locking femoral prosthesis in revision hip surgery in the elederly. Butler, Major M. Williams, M.R. Traer, E. Keenan, J. Combined Services Orthopaedic Society Meeting, Cannulated inter locking titanium alloy and hydroxyapatite coated implant in periprosthetic fracture treatment. Middleton, F.R. Trikha, S. Matthews, H. Raynam, O. Lewis, J. Ward, D.A. 7th Congress of EFORT, Lisbon, June Use of an interlocking hydroxyapatite coated stem in a patient with an infected non-union of a periprosthetic femoral fracture with massive bone loss. Trikha, S. MRCS et al. Journal of Bone and Joint Surgery AM. 2004; 86: Preliminary experience of the Cannulok revision hip prosthesis in late periprosthetic fracture management. Charnley, G and Anderson, G. Hip International Vol 12; The Plymouth experience of periprosthetic fracture management with a cannulated distally locked revision hip modular implant. Charnley, G. Anderson, G. Goddard, J.C. Revision 2000 International Conference; June A new cannulated distally locked femoral revision component to treat periprosthetic fractures and massive proximal femoral bone loss in hip arthroplasty. Charnley, G. Anderson, G. Goddard, J.C. 4th Congress of EFORT, Brussels, June Periprosthetic fractures of the proximal femur treated with cannulated distally locked stem. Conhyea, D. Alexander, T. Shannon, F.T. Paper at BOA/IOA Congress Solutions for periprosthetic fractures. Narang, K and Craig, D.M. Orthopedic Product News. July/September 1995 Cannulok Conceived in association with Mr Andrew Quaile FRCS and further developments based upon the clinical work conducted in collaboration with Mr Godfrey C Charnley FRCS, and other valued customers. Cannulok Plus Further developed in collaboration with Mr David Ward FRCS and other valued customers Orthodynamics remains totally committed to the development of Solutions in Orthopaedics CANNULOK is a registered trademark of Orthodynamics Ltd Cannulok Plus FEMORAL REINFORCEMENT A unique combination of modular revision hip prosthesis with locking intramedullary nail Other products from Orthodynamics : Logic MaydayNail OTHER PRODUCTS FROM THE SUMMIT MEDICAL GROUP : ORTHOPAEDIC IMPLANTS Orthopaedic accessories and consumables incorporating : BONE CEMENT MIXING AND ACCESSORIES BLOOD MANAGEMENT WOUND DRAINAGE / THEATRE DISPOSABLES For more information on all Summit Medical products visit: Orthodynamics Limited 10 Airfield Road Christchurch Dorset BH23 3TG United Kingdom Tel: +44 (0) Fax: +44 (0) info@orthodynamics.co.uk Website: Orthodynamics - A Summit Medical Group Company

2 REVISION HIP PROSTHESIS A unique combination of modular revision hip prosthesis with locking intramedullary nail Revision hip system for a wide range of clinical indications Cannulated to assist closed fracture reduction Distal locking for improved fixation Anterior bow reduces risk of anterior perforation and maintains stem closer to the centre of the canal Anatomical design, anteverted for preferred use in the intact femur, available in 240, 300 and 360mm lengths Available in four stem diameters 11, 13, 15 and 17mm Fully hydroxyapatite coated for enhanced cementless fixation, particularly where the proximal femur is deficient Available with standard or 45mm offset Increased proximal body options enabling greater proximal fill Modular head choice with options to maximise leg length adjustments or retention of existing acetabular component Comprehensive, updated instrumentation including distal targeting jigs 3

3 ADVANTAGES SOLUTIONS Closed procedure with standard guide wire technique helps preservation of blood supply with improved conditions for fracture healing Smaller exposure leads to reduced blood loss and reduced risk of infection Reduced soft tissue damage enables earlier mobilisation Fixation of the distal fragment controls rotation and shortening with earlier and more secure ambulation Multiple revision operations inevitably lead to the loss of proximal bone stock, particularly when associated with cement removal. The Cannulok Plus solution allows effective distal fixation allowing recovery of proximal bone stock over time. Apposition fit at the Isthmus with a fully HA coated prosthesis provides an elegant solution to this problem Periprosthetic femoral fractures below rigid metal hip prostheses are an increasing problem. Treatment with a conventional long stem prosthesis is less than satisfactory, due to the difficulties in guiding the stem through the fracture site during insertion and the problems of stabilising the distal femur without introducing bone cement around the fracture which compromises bony union The operative technique is simplified by design features which give the surgeon a degree of comfort in this difficult surgical area Cannulated reamers prepare the femur for the intended prosthesis Cannulated rasps ensure proximal profiling for press fit Cannulated trials allow impaction grafting to be considered Modular head components allow trial reduction to assess stability Distal targeting device facilitates placement of up to three locking screws (use of an image intensifier should be considered especially when implanting longer, slimmer stems) Distal locking screws have been designed specifically for the Cannulok Plus implant and have a shallow thread profile with self tapping flutes. This configuration achieves a balance of strength in both screws and femoral stem and eases insertion allowing for minor variations in alignment Primary proximal femoral fractures may present similar problems when treated with a conventional hip prosthesis or cause concern over survival of the femoral head when treated by intramedullary nailing or internal fixation alone 4 5

4 pre-operative planning SURGICAL TECHNIQUE CLINICAL INDICATIONS POSITIONING PREPARATION OF THE ACETABULUM Management of the grossly deficient proximal femur as a result of osteolysis Reinforcement of the femur where bone stock is depleted as a result of previous surgery Periprosthetic fractures around both total hip and hemiarthroplasty implants Femoral fractures and fractures around the trochanteric region complicated by metastatic bone disease Intraoperative fracture of the femur during hip arthroplasty Note: Use of an anatomical prosthesis is particularly indicated in situations where the femur remains intact and there would otherwise be a risk of perforating the anterior distal femoral cortex with any straight component. pre-operative planning The use of templates is recommended to establish the optimum size of prosthesis. The largest possible diameter implant should be used; this typically correlates to 1mm less than the final femoral reamer. Implant length should be selected to allow adequate bridging of the most distal defect. It is recommended that distal locking holes should be a minimum of 40mm below any femoral defect to avoid excessive stress concentration. Due to variations in patient anatomy, the bow of longer length femoral stems should be checked on a medial lateral X-ray. Fully HA coated stems are now offered in a choice of 240, 300 and 360mm lengths with standard or 45mm head offset. The shorter stem may be more suited to routine revision, where the femur is not fractured but reinforcement of the proximal region only is required. The existing femoral head diameter must be specified if the surgeon intends to retain the original acetabular component and the preferred head diameter advised where revision of both components is likely to occur. Multiple neck length adjustments are possible for 22.25, 26, 28 and 32mm metal heads. 28 and 36mm ceramic heads are also available. Biarticular and hemiarthroplasty head options ranging from 40-58mm may be specified. An image intensifier should be to hand, enabling: 1. The appropriate positioning of the reaming guide wire 2. Assistance with distal locking 3. Correct alignment It is important that the surgeon is familiar with closed intramedullary nailing techniques. The majority of cases involve the presence of a fracture around or below an implant or femoral deficiency requiring distal fixation and the technique described will reflect this. The patient is positioned on their side, on a radiolucent fracture table. The standard position used for total hip arthroplasty is eminently suitable. The patient is draped in the normal way incorporating any skeletal traction pins employed in the initial management as handles. The position of the image intensifier should be clarified with the radiographer at this stage. INCISION If appropriate, the old incision should be used. Alternatively, a standard lateral incision is recommended, the same as that used for total hip replacement. APPROACH Either a posterior or anterior type approach can be used. It is recommended however that the anterior approach be used to ease imaging. A modified Hardinge approach appears to give excellent access. This requires splitting of the fascia lata and tensor fascia lata, dissection of the gluteus medius and minimus from the greater trochanter and opening of the hip capsule. The Cannulok Plus system can be used with a wide variety of head sizes including hemiarthroplasty heads. The decision can therefore be made as to the most appropriate procedure required for the acetabulum. The size of the intended head is at the surgeon s discretion. The 28mm option allows up to 4 intraoperative neck length adjustments to maximise stability. Should a cup already be in place, secure and undamaged, then the appropriate head to match the existing implant should be requested when booking. 6 7

5 Distal locking jig handle SURGICAL TECHNIQUE Main body Proximal screw Centre screw Distal screw Barrel SURGICAL TECHNIQUE PREPARATION OF THE FEMUR TRIAL REDUCTION Image intensification is employed for preparation of the femur. For the anterior approach, the leg is swung over the table away from the surgeon. In the posterior approach, the leg is angled away from the lower leg on the table to provide visualisation. The X-ray picture is taken to check the fracture geometry and proximal femur. The original prosthesis is removed and any cement excavated proximally using dedicated revision instrumentation. A long drill may be employed to locate and drill through the centre of the proximal cement restrictor, taking care to image in multiple planes to ensure centralisation of the drill bit. A reaming guide wire should be passed at this stage, checking its passage on X-ray and that it is resting centrally in the distal femur with the fracture site reduced. Cannulated Orthodynamics reamers may be used to ream the femoral canal. For cementless fixation, over reaming by 1mm is recommended. This ensures optimal apposition of the HA coated implant to the host femur. If difficulty is experienced during trial or implant insertion, further reaming may be required. 4 Cannulated rasps are also an important consideration when optimising press fit of a HA coated prosthesis, and the appropriately sized rasp should always be selected to match the intended prosthesis. The proximal femur is then profiled with the cannulated rasp which passes over the guide wire. The correct amount of anteversion is controlled by the use of the rasp. 5 6 The femur should now be lavaged thoroughly to remove all debris. A cannulated trial prosthesis is passed over the guide wire using the 8mm trial introducer. A trial reduction is then performed with a suitable trial stem and test head. At this stage, it is often useful to employ some means of prophylactic cerclage to stabilise the fracture prior to insertion of the definitive prosthesis. Leg length is checked, and a landmark selected on the trial prosthesis for reference to the actual implant. JIG ASSEMBLY Once a suitably sized trial has been selected, the scrubbed assistant should set up the distal locking jig on the definitive prosthesis, and adjust the jig to ensure perfect alignment with the distal locking holes. The intended prosthesis is removed from its sterile packaging within the sterile field. The distal locking jig which corresponds to the implant length is selected. 7 The main body of the jig has a short spigot, which is inserted into the cannulation of the prosthesis. NOTE: occasionally the spigot needs lubricating with a gellonet type proprietary product. The 6mm distal locking jig handle passes through the jig and screws into the prosthesis securing the jig firmly in position. The jig must now be adjusted to match the definitive implant. 1. Slacken the distal, centre and proximal locking screws 2. Insert the 3-holed barrel into the distal section of the jig 3. Insert the 3 drill guides into the barrel and insert the 3 drill bits 4. On a flat and clean surface adjust the jig to allow the 3 drills to pass vertically through the distal locking holes in the implant 5. Tighten the locking screws in the following order: centre, proximal & distal ensuring that ALL drills pass smoothly through the stem after each adjustment 6. Remove drills and drill guides and set aside. Carefully unscrew the 6mm distal locking jig handle and place all components on a clean flat surface 8 9

6 SURGICAL TECHNIQUE SURGICAL TECHNIQUE 8 9 INTRODUCTION OF THE DEFINITIVE PROSTHESIS Do not use the jig as a stem introducer as doing so will result in unreliable screw positioning. Stem insertion must only be carried out with the prosthesis mounted on the 6mm implant introducer. Anteversion can be adjusted finally by means of the introducer The fracture rotation is checked on image intensifier once again. The reduction can be corrected by rotation of the distal fragment by the surgeon s assistant. TRIAL REDUCTION AND ADJUSTMENT OF NECK AND LEG LENGTH The surgeon has an extensive choice of femoral heads, both in terms of head diameter and neck length options. A trial reduction is carried out at this stage using the test heads provided and any adjustment for length established. DISTAL LOCKING Implant stability is usually achieved using the two most proximal screw holes. This also reduces stress concentration at the tip of the stem. A third distal screw hole is available should further fixation be required. Distal locking can be achieved by two means: By reattaching the distal locking jig. A small incision followed by soft tissue deflection using mosquito forceps will allow the drill guides to appose the lateral cortex of the femur. It is important to secure the drill guides by tapping gently. Once the drill guides are in position and secured, the middle hole is drilled. This drill bit is left in situ by detaching it from the drill chuck. THIS PROVIDES CRITICAL EXTRA STABILISATION OF THE JIG for preparing the proximal screw hole. Drill the proximal screw hole and remove the drill bit. NEVER REMOVE MORE THAN ONE DRILL BIT AT A TIME. Insert the depth gauge to identify the correct choice of self tapping distal locking screw and insert the screw. Remove the central drill bit, insert the depth gauge to identify the correct choice of self tapping distal locking screw and insert the screw. Additional fixation can be achieved by inserting the distal screw. Prepare and insert the screw using the method previously described. The jig can now be removed and the guide wire inserted to check that the proximal screw has passed through the implant. 2. Traditional means by free hand techniques. These vary to suit the particular technique and facilities, such as the availability of radiolucent drill guides or laser targeting devices available to the surgeon. The leg is positioned on the table to allow visualisation of a true lateral. The fracture reduction is again checked with particular regard to rotation. The radiographer is requested to visualise the distal portion of the prosthesis and to orientate the intensifier to reveal three perfectly round holes. A free hand technique using a sharp awl or K wire is recommended to find the point of entry central to the first hole. Both cortices are then drilled to 3.2mm using a standard European style hand drill guide. If the bone is particularly hard, a 3.9mm drill bit supplied in the Cannulok Plus instrument set is recommended for enlargement. The drill bit is removed from the drill chuck to check the position, making use of the image intensifier. If the surgeon is satisfied that the drill bit has engaged the hole in the prosthesis via both cortices, the drill bit may be used as a parallel reference for the second and the third [optional] locking screw. A depth gauge indicates the length of the screw required and the appropriate length 4.5mm selftapping screw is inserted with a standard hex screwdriver engaging both cortices. Before the hip is reduced, ensure that the appropriate femoral head is impacted to securely fit on the prosthesis. WOUND CLOSURE This is at the discretion of the surgeon, but suction drainage is recommended for the femur. POST OPERATIVE REGIME After postoperative X-rays have been taken to confirm satisfactory placement of the Cannulok Plus prosthesis, it is possible to mobilise the patient if the distal fixation is thought adequate. It is recognised that many patients to be treated with this technique will be unable to manage co-ordination of crutches or frames and partially weight bear. Otherwise it is advised that full weight bearing commence on the appearance of callus. Where proximal/mid femoral bone quality is compromised, restricted weight bearing is advised until reasonable bone quality and support is restored. 14 Before the hip is reduced, ensure that the appropriate femoral head is impacted to securely fit on the prosthesis

7 Case Histories Case Histories female, 59 female, 57 male, 64 female, 84 male, 69 female, 92 A woman with seropositive rheumatoid arthritis underwent revision hip surgery to a long stem cemented implant following early aseptic loosening. 7 years later the patient sustained an atraumatic unstable periprosthetic fracture. The stem was revised to a fully HA coated implant. 2 months postoperatively, a second stable periprosthetic fracture was sustained, and fixed with cable/plate fixation with use of autogenous iliac-crest bone graft. 2 years later, the patient presented with an infected non-union. All metalwork was removed leaving a grossly deficient proximal femur, ectatic in nature, with combined cavitary and segmental bone loss and discontinuity mid-shaft. 16 months postoperative, reconstruction with an HA coated Orthodynamics Cannulok Stem confirms fracture union and bone ingrowth in all areas of the prosthesis. Courtesy of Mr. S. Trikha Investigation performed at Worthing and Southlands Hospitals Trust, West Sussex This patient suffered from TB of the right hip in childhood. 7 years after a Girdlestone excision arthroplasty of the right hip a revision for coagulase negative Staphylococcal infection produced a right total hip with periprosthetic fracture. Preoperative an aspiration, plasma viscosity, CRP, and MRI scan were performed. Intraoperatively the Trident all poly constrained cemented acetabular component was fitted with a 15 / 300 mm Cannulok HA coated stem and locked distally. At the 4 month review, the patient was showing excellent post operative pain relief but was slow to mobilise due to shoulder problems Courtesy of Mr. Jonathan Keenan FRCS Derriford Hospital, Plymouth This patient sustained a closed, mid-shaft femoral fracture amongst multiple other injuries. His femoral fracture was fixed with a locked intramedullary nail and he underwent exchange intramedullary nailing for non-union 21 months after fracture. The non-union persisted and he later developed symptomatic osteoarthritis of the ipsilateral hip. At 33 months from initial injury a custom made, fully HA coated Cannulok femoral stem was inserted across the non-union with a ceramic head and an uncemented cup. Autograft from reaming the femoral head and acetabulum was placed at the fracture site. Femoral union was achieved by 7 months and the hip arthroplasty functions well at 6 years. Courtesy of Mr. C Andrews FRCS Scarborough Hospital, East Yorkshire This lady presented with a periprosthetic fracture of the right femur (Vancouver B1) following the implantation of a Charnley primary stem. Initially, the fracture was fixed using Zimmer cable grip system and bone graft. This fixation failed. The metalwork was removed and a trochanteric osteotomy performed. A Cannulok hydroxyapatite coated stem was implanted with strut graft. The latest review was 3.5 years post surgery and the patient was able to mobilise independently using 1 stick, pain free. Courtesy of Mr. Jonathan Keenan FRCS Derriford Hospital, Plymouth This patient has had a right cemented total hip replacement in 1985 and a left cemented total hip replacement in Both hips required revision due to aseptic loosening of the cemented femoral implants in 1991 and again cemented implants were used. In 2004 the patient presented again with aseptic loosening of the implants on both sides. The second revision of right hip with an uncemented stem and acetabular constraint. Uneventful recovery but readmission with periprosthetic fracture dislocation 14 days after discharge. The femoral component was exchanged to the Cannulok system with distal locking with an uneventful recovery. A second revision of left hip with the Cannulok distal locking stem and a press fit acetabular cup in Patient still plays golf with a single figure handicap. Courtesy of Mr. LM Koch Dewsbury and District Hospital 45 months after successful cemented total hip replacement this patient fell and sustained femoral periprosthetic fracture with loosening of the femoral component. The femoral component was revised with a 300 x 15mm HA coated Cannulok stem and 22.25mm cobalt chrome head through a trochanteric osteotomy. Weight bearing was protected for 6 weeks. The fracture and osteotomy united by 6 months. The hip functioned well. Courtesy of Mr. C Andrews FRCS Scarborough Hospital, East Yorkshire 12 13

8 (Ti-6Al-4V/HA) Femoral stems LEFT ANTERIOR BOW LEFT and Anteverted RIGHT ANTERIOR BOW RIGHT and Anteverted Stem Length Stem Diameter Standard Offset 45 Offset Standard Offset 45 Offset 11mm CLKLHA 11/240 CLKLHA 11/ CLKRHA 11/240 CLKRHA 11/ mm 13mm CLKLHA 13/240 CLKLHA 13/ CLKRHA 13/240 CLKRHA 13/ mm CLKLHA 15/240 CLKLHA 15/ CLKRHA 15/240 CLKRHA 15/ mm CLKLHA 17/240 CLKLHA 17/ CLKRHA 17/240 CLKRHA 17/ mm CLKLHA 11/300 CLKLHA 11/ CLKRHA 11/300 CLKRHA 11/ Ordering information 300mm 360mm Screw Diameter 4.5mm (Ti-6Al-4V) Distal locking Screws Screw length mm 13mm CLKLHA 13/300 CLKLHA 13/ CLKRHA 13/300 CLKRHA 13/ mm CLKLHA 15/300 CLKLHA 15/ CLKRHA 15/300 CLKRHA 15/ mm CLKLHA 17/300 CLKLHA 17/ CLKRHA 17/300 CLKRHA 17/ mm CLKLHA 11/360 CLKLHA 11/ CLKRHA 11/360 CLKRHA 11/ mm CLKLHA 13/360 CLKLHA 13/ CLKRHA 13/360 CLKRHA 13/ mm CLKLHA 15/360 CLKLHA 15/ CLKRHA 15/360 CLKRHA 15/ mm CLKLHA 17/360 CLKLHA 17/ CLKRHA 17/360 CLKRHA 17/ Part Number 25 DLS DLS DLS DLS DLS DLS DLS DLS DLS 65 HEMIARTHROPLASTY HEADS (Ti-6A1-4V) Head Diameter FEMORAL HEADS (CoCr) Neck Length Product Code Reduced Standard Extended Extended Extended 22mm Co 22 FH Co 22 FHE Co 22 FHEE 26mm Co 26 FH Co 26 FHE Co 26 FHEE 28mm Co 28 FHR Co 28 FH Co 28 FHE Co 28 FHEE 32mm Co 32 FHR Co 32 FH Co 32 FHE Head Diameter 28mm 36mm CERAMIC FEMORAL HEADS (ZrO 2 ) Neck Length (Includes Standard & Extended Neck Sleeves) Product Code Zr 28 FH/E Zr 36 FH/E BIARTICULAR HEADS (CoCr/UHMWPE/Ti-6A1-4V) Head Diameter Product Code Head Diameter Product Code 40mm SI HAH 40 40mm SI BAH 40 42mm SI HAH 42 42mm SI BAH 42 44mm SI HAH 44 44mm SI BAH 44 CUSTOM PROSTHESES The Cannulok Plus prosthesis is one of the more common templates upon which many of our custom manufactured components are based. This often includes: - Supplementary distal locking options Anterior screw holes Exaggerated anatomic bows Increased and intermediate stem lengths Variations to HA coatings MATERIALS SPECIFICATION The Cannulok Plus system is manufactured in high strength forged Titanium (Ti-6A1-4V) for maximum fatigue strength. Recommendations to clinicians The Cannulok revision system has been used successfully in a large number of patients since The number of stem failures experienced during this period has been extremely small (<0.06%) Laboratory fatigue testing under simulated clinical conditions in accordance with International Standards suggests: 1) That even the smallest diameter implant is safe provided a moderate level of femoral support is achieved 2) That where proximal/mid femoral bone quality is compromised, restricted weight bearing is advised until reasonable bone quality and support is restored. These recommendations are directed principally towards use of smaller diameter prostheses. It is recommended that the largest diameter stem should always be selected, consistent with patient anatomy and bone preservation. custom prostheses 46mm SI HAH 46 46mm SI BAH 46 48mm SI HAH 48 48mm SI BAH 48 50mm SI HAH 50 50mm SI BAH 50 52mm SI HAH 52 52mm SI BAH 52 54mm SI HAH 54 54mm SI BAH 54 56mm SI HAH 56 56mm SI BAH 56 58mm SI HAH 58 58mm SI BAH