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Knee arthrodesis—A review
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The Knee 15 (2008) 247 – 254
Review
Knee arthrodesis—A review H.S. Somayaji a,b,d,e,⁎, P. Tsaggerides a,d , H.E. Ware c,f , G.S.E. Dowd a,d a
f
Royal Free Hospital, Pond Street, London NW3 2QG, UK b NMC Speciality Hospital, Abu Dhabi, UAE c Chase Farm Hospital, London UK d Department of Orthopaedics, Royal Free Hospital, Pond Street, London NW3 2QG, UK e Department of Orthopaedics, NMC Speciality Hospital, Abu Dhabi, UAE Department of Orthopaedics, Chase Farm Hospital, The Ridgeway, Enfield, Middlesex, London EN2 8JL, UK Received 4 October 2007; received in revised form 18 March 2008; accepted 19 March 2008
Abstract Knee arthrodesis as a primary treatment method for knee arthritis has re-emerged as a salvage procedure for failed knee arthroplasty. This article is an overview of indications, contraindications, principles, preoperative preparation and surgical techniques of knee arthrodesis. Their advantages and disadvantages are discussed together with results and complications. An attempt has also been made to incorporate technical considerations, the author's preferred surgical techniques and indications for the various methods of arthrodesis. © 2008 Elsevier B.V. All rights reserved. Keywords: Arthrodesis; Knee arthroplasty; Intramedullary nail; External fixator; Bone loss
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Introduction . . . . . . . . . . . . . Indications . . . . . . . . . . . . . Contraindications . . . . . . . . . . Preoperative preparation . . . . . . Technical considerations . . . . . . 5.1. Energy expenditure . . . . . 5.2. Ideal alignment . . . . . . . 5.3. One or two stage procedure . 5.4. End point of arthrodesis . . . 5.5. Methods of fixation . . . . . Intramedullary fixation . . . . . . . 6.1. Long nail . . . . . . . . . . 6.2. Modular nail. . . . . . . . . 6.3. Non-modular nail . . . . . . 6.4. External fixation . . . . . . . 6.5. Monoplanar fixators . . . . . 6.6. Biplanar fixators . . . . . . . 6.7. Circular frames . . . . . . . 6.8. Compression plating . . . . . 6.9. Vascularised fibular graft . .
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⁎ Corresponding author. Department of Orthopaedics, Royal Free Hospital, Pond Street, London NW3 2QG, UK. Tel.: +44 7732715505. E-mail addresses: [email protected], [email protected] (H.S. Somayaji). 0968-0160/$ - see front matter © 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.knee.2008.03.005
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6.10. Authors preferred technique. 6.11. Newer prosthetic options . . 6.12. Alternate treatment options . Conflict of interest statement . . . . . . References . . . . . . . . . . . . . . . .
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1. Introduction Total knee replacement is an established and highly successful surgical procedure. However as the indications for primary knee replacements are increasing, so are the complications associated with them. Management of an infected total knee replacement is a universal problem faced by the orthopaedic surgeon. Nelson and Evarts [1] first described knee arthrodesis as a treatment option for failed knee arthroplasty in 1971. The irretrievably failed total knee replacement (TKR) is the main indication for knee arthrodesis at present. When successful, arthrodesis is effective in relieving pain, restoring stability and improving patient function and mobility. 2. Indications Like many reconstructive procedures, arthrodesis of the knee has undergone an evolution in both indications and techniques. In the late 19th and early 20th centuries, knee arthrodesis was the primary treatment for septic arthritis, tuberculosis and poliomyelitis [2–5]. It was also one of the mainstays of treating osteoarthritis and rheumatoid arthritis. Improved anti-tubercular medications have significantly reduced the involvement of knee joint with tuberculosis. Global vaccination programmes have tackled the problems associated with poliomyelitis. In addition excellent results achieved by modern knee arthroplasty surgery have replaced arthrodesis as the treatment option for osteoarthritis and rheumatoid arthritis. At present failed total knee replacement mainly due to infection is the most common indication for knee fusion [5]. The general indications for arthrodesis for an infected total knee replacement are the presence of resistant organisms, an immune compromised patient, gross instability, inadequate skin and soft tissue coverage, deficient extensor mechanism or where the patient is unwilling to consider a revision arthroplasty [5–8]. 3. Contraindications Contraindications for knee arthrodesis include contralateral knee amputation and presence of advanced degenerative changes in the ipsilateral hip or ankle [5,6]. Presence of arthrodesis of the contralateral hip or knee is a relative contraindication. Successful knee fusion is associated with compensatory mechanisms in the spine, hip and ankle. These are an increase in pelvic tilt, hip abduction and ankle dorsiflexion on the ipsilateral side. As a result, the degenerative changes in the ipsilateral hip or ankle affect the compensatory mechanisms and result in poor ambulation and increased energy expenditure [5]. Patients with severe degenerative changes in the spine are also poor candidates for
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knee fusion as compensatory mechanisms lead to increased forces on the lumbar spine resulting in worsening of the spinal problem. 4. Preoperative preparation Extensive preoperative preparation is essential to achieve overall success with the knee fusion. This includes assessment of systemic problems such as immuno-suppressive medication, diabetes mellitus, renal failure, liver disease, peripheral vascular disease, cardiac problems, chronic obstructive pulmonary disease etc. This is not only to optimise their health prior to anaesthesia and surgery but also to prepare them for increased energy expenditure required after knee fusion. Doppler assessment of the peripheral pulses, assessment of capillary refill, local neurological status, status of the overlying skin and soft tissues are crucial as in the case of any knee surgery. It is likely that patients requiring arthrodesis would have had multiple previous surgeries with multiple incisions. Careful assessment of all the scars is important. It is highly advisable to obtain advice from the plastic surgeon regarding placement of an appropriate incision. As most of the blood supply to the skin overlying the knee comes from the perforating vessels on the medial side, any further medial incisions should be avoided [6,9]. Assessment of the knee joint itself consists of alignment, fixed deformities, range of movement, extensor lag as well as ligamentous stability. Careful assessment of the function of the ipsilateral and contralateral hip joints, ipsilateral ankle, contralateral knee as well as examination of the spine is mandatory. Radiological investigations consist of standing anteroposterior view and a lateral view including long-leg films to assess alignment and limb length discrepancy. It is imperative to obtain all the previous surgical details as some of the implants in failed knee replacement may need special extraction devices. The use of a cylinder cast or a knee brace locked in extension during the preoperative period enables the patient to understand their post knee fusion status particularly with regards to ambulation and other day to day activities [6]. 5. Technical considerations 5.1. Energy expenditure Experimental studies have shown that energy required to walk with an arthrodesed knee is about 30% higher than that required for normal walking. The energy required to walk with an above-knee amputation is about 25% greater than that required with an arthrodesed knee. Patients with a knee arthrodesis use 0.16 mL/kg/min oxygen compared to 0.20 mL/kg/min following an above-knee amputation [5,10].
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5.2. Ideal alignment The application of sound fracture management principles will result in a better outcome at any attempted knee fusion. Success depends on achieving good bony contact, preservation of vascularity and rigid fixation. The aim should be to attain an overall limb alignment with the knee in 5–7° of valgus and 15 ± 5° of flexion [5,6,11]. Knee arthroplasty cutting instrumentation may facilitate such a position but their usefulness in the presence of extensive bone loss is limited. Although anterior bow of a long intramedullary nail can provide slight flexion, such a device requires the position of near full extension. The ideal position of flexion and valgus can however be achieved with modular nailing, external fixation and plating techniques [12–14]. It is imperative that minimal bony resection is undertaken to maintain leg length. Bone loss at the time of surgery can be classified according to the system proposed by Klinger et al. [15]. 1. Mild—full bony contact possible. 2. Moderate—incomplete bony contact. 3. Severe—minimal or no bony contact. If there is severe bone loss, additional bone grafting procedures including vascularised fibular graft or allograft techniques should be considered. Application of ring fixators is another option. 5.3. One or two stage procedure
projections [15,18]. After union is achieved overall alignment of the limb should be measured using long-leg films (Fig. 1). 5.5. Methods of fixation The success rate of arthrodesis depends on the method, surgical technique and host factors. Massive bony defects, vascular insufficiency and inadequate soft tissue envelope may compromise any situation. Options for fixation of a knee arthrodesis include external fixators of various configurations, long or short intramedullary nails and internal fixation with plates or combination of implants. Supplemental bone graft should follow the principles of general infection management. The application of graft is not recommended in acutely infected sites [5–8]. Autograft and allograft have been used to supplement large defects in many cases. A vascularised fibular graft has been used successfully in a small number of patients in conjunction with internal fixation [19,20]. 6. Intramedullary fixation Intramedullary devices can either be long nails or short nails of modular and nonmodular types. Rigid fixation, early mobilisation and shorter times to achieve fusion have been reported to be the advantages of intramedullary nailing [21,22]. Additional advantages of intramedullary fixation are lower reported rates of major complications such as recurrent infection, wound breakdown, failure of hardware and the need for additional bone grafting. The complication rate after knee arthrodesis using other methods has been as high as 85% [21].
Knee arthrodesis in cases of infection can be performed either as a single stage or as a two stage procedure. A single stage arthrodesis consists of adequate debridement of any infected tissue and insertion of a fixation device. Following prior surgical procedures resulting in a failed and infected arthroplasty, knee arthrodesis should ideally be attempted as a two stage procedure [16]. The first stage consists of surgical debridement, removal of components and insertion of an antibiotic impregnated cement spacer. This is followed by 6– 8 weeks of antibiotic treatment based on microbiology results from the tissues and serial estimation of inflammatory markers. Antibiotics are then discontinued for about two weeks and inflammatory markers are rechecked. Second stage of arthrodesis is subsequently carried out using the chosen mode of fixation. Several authors have demonstrated that one stage arthrodesis using an intramedullary nailing is safe and effective and not associated with recurrent infection in the absence of virulent organisms, polymicrobial infection or gram negative organisms [11,17]. External fixators, particularly ring fixators are more appropriate in such adverse situations [5,6,13,14]. 5.4. End point of arthrodesis Arthrodesis is considered to be successful when bony trabeculae traverse from tibia to femur in at least two radiographic
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Fig. 1. 4 months post-operative radiograph.
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Wilde and Stearns [22] in their series described a mean time to fusion of 6.6 months using an intramedullary nail. The mean time to fusion following nailing in the study by Waldman et al. [16] was 6.3 months with no patient requiring more than 11 months achieving fusion. Intramedullary nailing has numerous potential disadvantages. The surgical technique is challenging and requires extensive exposure of the joint. Care must be taken to assure maximum bony contact between the two bony surfaces. Shortening of the limb is of concern. However, structural bone graft or an artificial spacer can be placed if significant shortening is anticipated [23]. Recurrence of infection is always a danger. It can present itself as persistent pain in spite of successful union achieved during arthrodesis. The presence of an implant in the intramedullary canal would pose special problems if the infection recurred. An infected nail can be removed by making a large anterior cortical window and removing it in segments using a high speed drill. An additional potential problem is the lack of compression applied at the time of nailing. Although weight bearing does provide some compression, the nail may not achieve the compression force that a dynamic compression plate or an external fixator can provide. However, the reasonable time to fusion observed in the various reports suggest that adequate compression is probably achieved [5,6]. Migration of the nail has been reported. Donley et al. [24] reported this complication in their series of twenty patients treated with an intramedullary nail introduced through the pyriform fossa. In their study, twelve patients had the nail secured proximally and eight did not. Two of the eight unsecured nails migrated proximally necessitating removal of the nail. A secure fit between the intramedullary canal and the nail in addition to the proximal flutes helps to prevent migration. Proximal migration can also be prevented by using the locking mechanism. 6.1. Long nail Use of a long intramedullary nail inserted via pyriform fossa approach is a technically demanding procedure. This is accomplished by inserting a nail in an antegrade fashion down the length of femur passing through the knee joint up to the distal third of tibia [24,25]. Another technique is to pass the nail in a retrograde manner from the knee joint through the femur out of the buttock region followed by its antegrade insertion down the tibia. Both these techniques require prolonged operating time and are associated with increased blood loss [5,6,11,17]. Other potential complications include problems with sterilisation, migration of the nail, breakage, neurovascular injury, intraoperative fractures of the femur or tibia, delayed or nonunion and gluteal pain [11,17]. Contraindications for such devices include the presence of an ipsilateral total hip replacement, gross deformity of the femur or tibia or the presence of active infection [5]. Puranen et al. [11] in their series of 33 patients with knee fusion by a long intramedullary nail, reported union in 87% of patients. Fifteen of the procedures were done for a failed knee arthroplasty; eight had failed because of infection and seven because of aseptic loosening. Twenty-nine of the thirty-three
knees united 3 to 4 months after the first attempt at arthrodesis and three united after technical errors were corrected. One attempt at arthrodesis resulted in a broken nail and nonunion. The functional results were satisfactory in all patients. In a recent report, Bargiotas et al. [25] reviewed the outcome of a staged approach for arthrodesis of the knee with a long curved intramedullary nail after the failure of a total knee arthroplasty due to infection. They reported the results for twelve patients who underwent knee arthrodesis after an average follow up of 4.1 years. Solid union was achieved in 10 of the 12 knees. The average time to union was 5.5 months. The average limblength discrepancy was 5.5 cm. The mean WOMAC score improved from 41 to 64 points. They recommend an arthrodesis with the technique involving convex-to-concave preparation of bone ends to provide a painless functional gait with low complication and re-operation rates. 6.2. Modular nail A modular system is attractive as a fusion device. In contrast to a one-piece intramedullary nail, the modular system has two components with a stable coupler, which allows for a more accurate fit of the nail in the intramedullary canal by accommodation of the nail to the contour of the femoral shaft, thus reducing the risk of fracture during insertion. Intramedullary fixation with this device has the advantage of allowing debridement of the knee followed by insertion of the nail using one of the previous knee incisions. This avoids the need for making a surgical approach to the pyriform fossa as required with an antegrade nail. It also allows for an alteration in size between the intramedullary canals of the femur and tibia and to obtain correct alignment [26,27]. Bone loss can be addressed with a metal or polyethylene spacer or bone grafting. One of the key advantages of such devices is the ability to allow immediate full weightbearing which allows compression across the arthrodesis site resulting in faster fusion. White et al. [27] reported the use of customised coupled nail (Mayday Arthrodesis Nail) in nine patients of which five were for infected arthroplasty. Union was achieved in all patients (100%) at a mean time of 10 months using the customised implant. There were no complications despite early weightbearing. No further procedures were required. This contrasted with a rate of union of 53% and a complication rate of 76% with alternative techniques. They conclude that a customised coupled intramedullary nail can give excellent stability allowing early weightbearing and results in a high rate of union with minimal postoperative complications. Arroyo et al. [28] reported a 90% success rate in 19 of 21 knees treated with a modular nailing system. Their study included patients who underwent arthrodesis after tumour resection and patients with aseptic loosening following total knee replacement. They reported a mean time to fusion of 8.4 months and an overall satisfaction rate of 94%. Hinarejos et al. [29] reported a case of femoral and tibial fractures at each end of a modular nail in a solidly fused knee 8 months after an arthrodesis. They had to remove the Wichita fusion nail used for arthrodesis via the femoral fracture site and
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use a custom made femoro-tibial interlocking nail as a definitive treatment. 6.3. Non-modular nail Lai et al. [17] reported the results of their series involving 33 patients where arthrodesis was attempted using a short nonmodular Huckstep nail after failure of a non-constrained total knee arthroplasty. Three knees had earlier failed attempts at arthrodesis using external fixation. The Huckstep nail was inserted through the knee, retrograde into the femur, and then antegrade into the tibia. Local bone graft was used in all knees. After an average follow up of 47 months, 91% of their patients had radiological signs of union. The average time to union was 5.2 months. In their series of 17 patients, Goldberg et al. [30] achieved fusion in 13 patients using Huckstep nail for failed knee arthroplasty. Their technique involved using a long Huckstep nail in an antegrade manner similar to the use of a long straight Kuntscher nail, which was the original technique described by Huckstep. 6.4. External fixation A knee arthrodesis can be achieved in an infected total knee arthroplasty using an external fixator. They can be of monolateral monoplanar, bilateral monoplanar, monolateral biplanar, bilateral biplanar or multiplanar types [31,32]. In addition, circular frames such as Ilizarov as well hybrid fixator frames have been used in achieving knee arthrodesis. The use of wireless computer navigation system in achieving knee arthrodesis using external fixators has also been reported [33]. 6.5. Monoplanar fixators External fixators were pioneered as a method of achieving knee arthrodesis by Charnley and Baker [2]. His technique consisted of using two femoral pins, two tibial pins and a Thomas splint to maintain compression at the site of fusion [2,5]. However, this technique was used mainly for the primary treatment of osteoarthritis and infective arthritis. He reported an excellent result which was due to the optimal bony contact between the femoral and tibial segments as well as compression obtained using the external fixation. However, use of monoplanar fixators to achieve fusion in a failed knee arthroplasty has not met with similar success. This is attributed to the minimal stability offered by such devices in the sagittal plane. Hak et al. [18] reported failure of 9 monoplanar fixators in achieving fusion in 19 patients. 6.6. Biplanar fixators This system consists of transfixation pins in the femur and tibia as well as additional pins placed anteriorly. Compared to uniplanar fixators, biplanar fixators provide optimal mediolateral stability [31]. Knutson et al. [34] reported that fixator configuration with sagittal pins connected to an anterior fixator provide the greatest
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stiffness. They also reported increased stability and better fusion rates compared to unilateral fixator design. However, Hak et al. [18] reported a similar union rate but higher complication rate in their series of 17 patients who had knee arthrodesis with biplanar external fixators. 6.7. Circular frames Although conventional monoplanar and multiplanar fixators are easier to apply, the poor rate of fusion achieved with such devices and the higher complication rate has resulted in their infrequent use to-date. Application of circular frames requires considerable surgical skill to obtain stable compression with good alignment. However, they offer potential advantages. The main advantages of Ilizarov method are the ability to provide a mechanical stimulus for bone formation, to provide rigid fixation and vary the rigidity during treatment, to modify alignment of the arthrodesis using hinges and to perform a simultaneous limb lengthening [21,35–37]. In addition, their use has no risk of intramedullary dissemination of the infection and allows easy removal of the hardware. The disadvantages of arthrodesis and subsequent bone transport using the Ilizarov technique include pin loosening, pin site infection, delayed weightbearing, delayed fusion and the inconvenience associated with a long treatment period. In their study, Manjotti et al. [37] reported the fusion rate to be 100% using Ilizarov frames to achieve knee fusion. Despite studies showing a need for bone grafting in 5% to 42% of patients in some series treated with an external fixator, no patient in their study required bone grafting to achieve union. Arthrodesis was achieved after a mean duration of 6.8 months, which is consistent with that found in other studies using external fixation or an intramedullary nail. The problem of delayed weightbearing was addressed by modifying the technique to use half-pins. In the patients in whom half-pins were used, full weightbearing was allowed immediately after surgery. Oostenbroek et al. [36] reported their experience of using the Ilizarov technique in 15 patients, achieving a rate of union of the arthrodesis of 93%. They reported that 53% of these patients had undergone earlier attempts at arthrodesis and most had long-standing osteomyelitis and were elderly. The rate of complications related to their treatment was 80%. In their experience many complications were related to poor quality and quantity of available bone. The mean total duration of treatment with their technique was 51 weeks. They also reported that when the arthrodesis was performed under adverse clinical conditions, for example where the infection was difficult to control, the treatment time was more than a year. An Ilizarov arthrodesis has the advantage that it can be performed in the presence of active infection. The infection subsides with continuous axial compression and treatment with antibiotics, with the arthrodesis proceeding to union [36]. 6.8. Compression plating Use of one or two plates after preparing the femoral and tibial segments for arthrodesis has also been attempted [38–40].
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Advantages of this technique include combining debridement and implantation with the same incision and the ability to achieve compression at the site of arthrodesis. In the series published by Pritchett et al. [38], 26 patients had an arthrodesis of the knee using a single anterior tension band compression plate of which six were for failed knee arthroplasties. After a minimum of 2 year follow-up period solid osseous union occurred in all patients. Munzinger et al. [39] achieved successful union in 27 of 34 knees with the use of a single large laterally applied plate. Nichols et al. [40] used a dual plating technique where dynamic compression plates were applied on the medial and lateral sides. All 11 patients achieved union at a mean duration of 5.6 months. Kuo et al. [41] reported the use of a dual locking compression plating technique to achieve fusion in three patients who had failed infected non-reconstructable total knee arthroplasties with 100% success rate. It is important to note that these patients were kept non-weightbearing in a long-leg cast for 3 months followed by a hinged knee brace locked in extension. Weightbearing was gradually allowed to full over 1 month period. 6.9. Vascularised fibular graft It is not uncommon to encounter the problem of large osseous defects in the knee following multiple attempts at reconstructive surgery. Conventional methods of achieving arthrodesis are unlikely to result in successful outcome as gross shortening of the extremity or nonunion are more likely. Use of vascularised ipsilateral fibular graft in addition to an intramedullary fixation device is an option [19,20]. The repair process is likely to be more rapid and the strength and stiffness are likely to be superior to the joints which have been treated with an autogenous non-vascularised graft (iliac crest bone graft). These procedures are technically demanding and should be performed in conjunction with a microvascular surgeon. In a study published by Rasmussen et al. [19], 12 of the 13 patients achieved fusion after an average follow up of 51 months. The other patient who had multiple previous reconstructive attempts required an amputation. The average duration of surgery was 8.5 h and average blood loss was 2322 mL. Usui et al. [20] in their series of 17 patients achieved successful union in 16 patients using vascularised fibular graft. Use of allograft and sliding femoral and tibial grafts are also the other means of filling any large bony defects [6]. 6.10. Authors preferred technique We prefer the modular nailing system (Mayday arthrodesis nail—(Orthodesign, Christchurch, UK) for achieving knee arthrodesis in our units. This is a two part nail, where both components are inserted via a single knee incision often through the original incision from previous knee surgery. Subsequently two components are joined by a single antero-posterior locking pin to form a solid nail. The tibial component is locked by means of a targeting device, whilst the femoral component is
unlocked to facilitate compression with early weightbearing. However patients are discouraged from applying excessive rotational forces on the components and a knee brace is used for 3 weeks to assist compliance. Each nail is customised to suit individual patient's anatomy. The femoral component is designed to be stable in rotation although supplementary locking remains an option. 6.11. Newer prosthetic options It is imperative to carefully analyse an unsuccessful TKR to accurately determine the reason for failure. Once this has been done, it is necessary to determine, on a case-by-case basis, whether revision surgery is reasonable. A team approach is often useful for this process and may involve advice from the physicians, anaesthetic team, plastic surgeons, vascular surgeons, microbiologist and inputs from the patient and family. Availability of new prosthetic materials allows the surgeon to consider reconstruction rather than amputation or resection if encountered with severe bony or soft-tissue defects [42]. Developments in tumour surgery have also contributed to the reconstructive efforts in failed knee replacement surgery. Structural allograft composites, custom prostheses fabricated from porous tantalum or massive prostheses can address some of the problems associated with extensive bone loss. Structural allograft composites have shown satisfactory intermediate-term results, but long-term results are still awaited [42–44]. The introduction of porous tantalum offers another option for the reconstruction of bony defects. Identical cell structure to cancellous bone, availability in complex shapes, fatigue resistance, excellent frictional characteristics and long term stability are some of the key advantages of this material [45]. Gupta et al. [46] have reported the use of a non-invasive growing endoprosthesis to achieve limb length equality and pain free walking in one of their patient who had a failed complicated second revision knee arthroplasty. However it is important to note that none of the available treatments absolutely rule out the possibility of recurrent infections in the limb. 6.12. Alternate treatment options The other alternatives to arthrodesis are chronic antibiotic suppression, artificial arthrodesis, resection arthroplasty and amputation. Antibiotic suppression is usually not effective with an overall success rate of about 27% [5,6,47]. Voss in 2001[47] reported the new concept of artificial arthrodesis in the management of severely infected knee arthroplasty. It consists of inserting a long intramedullary nail through a large cement spacer in the knee and to allow immediate full weightbearing. Amputation or resection arthroplasty should be considered in cases of life-threatening infection, persistent infection, irreparable soft-tissue deficiency, extensive bone loss and the wishes of the patient following multiple failed attempts at reconstructive surgery. Resection arthroplasty is best tolerated by low
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demand patients who are already disabled because of multiple joint involvements [48]. The prevalence of amputation following total knee arthroplasty ranges from 0.02% to 0.18%, but it can be as high as 6% in patients with a chronic infection at the site of a total knee replacement [40,49]. Isiklar et al. [49], in a study of amputation following total knee replacement, found that patients had undergone an average of six surgical procedures prior to having an amputation. In a series of patients who had a repeated infection following insertion of revision components for an infection at the site of a total knee replacement, Hansen et al. [50] found that patients had undergone an average of thirteen surgical procedures. Conflict of interest statement This is to confirm that we have not received any outside funding or grants in support of our research or preparation of the manuscript. We or a member of our immediate family, have not received from any commercial entity any payments or any pecuniary, in kind, or other professional or personal benefits any commitment or agreement to provide such Benefits that were related in any way to the subject of the work or the research that we conducted in connection with the work. References [1] Nelson CL, Evarts CM. Arthroplasty and arthrodesis of the knee joint. Orthop Clin North Am 1971;2(1):245. [2] Charnley J, Baker SL. Compression arthrodesis of the knee: a clinical and histological study. J Bone Joint Surg Br 1952;34-B(2):187. [3] Hibbs RA. The treatment of tuberculosis of the joints of the lower extremities by operative fusion. J Bone Joint Surg 1930;12:749. [4] Soto-Hall R. Fusion in charcots disease of the knee: new technique for arthrodesis. Ann Surg 1938;108:124. [5] Conway JD, Mont MA, Bezwada HP. Arthrodesis of the knee. J Bone Joint Surg Am 2004;86-A(4):835. [6] MacDonald JH, Agarwal S, Lorei MP, Johanson NA, Freiberg AA. Knee arthrodesis. J Am Acad Orthop Surg 2006;14(3):154. [7] Vlasak R, Gearen PF, Petty W. Knee arthrodesis in the treatment of failed total knee replacement. Clin Orthop Relat Res 1995;321:138. [8] Windsor RE. Knee arthrodesis. Surgery of the knee. New York, NY: Churchill Livingstone; 1993. p. 1103. [9] Vince KG. Revision knee arthroplasty technique. Inst Course Lect 1993;4242:325. [10] Waters RL, Perry J, Antonelli D, Hislop H. Energy cost of walking of amputees: the influence of level of amputation. J Bone Joint Surg Am 1976;58(1):42. [11] Puranen J, Kortelainen P, Jalovaara P. Arthrodesis of the knee with intramedullary nail fixation. J Bone Joint Surg Am 1990;72(3):433. [12] Incavo SJ, Lilly JW, Bartlett CS, Churchill DL. Arthrodesis of the knee: experience with intramedullary nailing. J Arthroplasty 2000;15(7):871. [13] Salem KH, Keppler P, Kinzl L, Schmelz A. Hybrid external fixation for arthrodesis in knee sepsis. Clin Orthop Relat Res 2006;451:113. [14] Wiedel JD. Salvage of infected total knee fusion: the last option. Clin Orthop Relat Res 2002;404:139. [15] Klinger HM, Spahn G, Schultz W, Baums MH. Arthrodesis of the knee after failed infected total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc 2006;14(5):447. [16] Waldman BJ, Mont MA, Payman KR, Freiberg AA, Windsor RE, Sculco TP, et al. Infected total knee arthroplasty treated with arthrodesis using a modular nail. Clin Orthop Relat Res 1999;367:230.
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[17] Lai KA, Shen WJ, Yang CY. Arthrodesis with a short Huckstep nail as a salvage procedure for failed total knee arthroplasty. J Bone Joint Surg Am 1998;80(3):380. [18] Hak DJ, Lieberman JR, Finerman GA. Single plane and biplane external fixators for knee arthrodesis. Clin Orthop Relat Res 1995;316:134. [19] Rasmussen MR, Bishop AT, Wood MB. Arthrodesis of the knee with a vascularized fibular rotatory graft. J Bone Joint Surg Am 1995;77(5):751. [20] Usui M, Ishii S, Naito T, Wada T, Nagoya A, Takahashi T, et al. Arthrodesis of knee joint by vascularised fibular graft. Microsurgery 1996;17(1):2. [21] Garberina MJ, Fitch RD, Hoffmann ED, Hardaker WT, Vail TP, Scully SP. Knee arthrodesis with circular external fixation. Clin Orthop Relat Res 2001;382:168. [22] Wilde AH, Stearns KL. Intramedullary fixation for arthrodesis of the knee after infected total knee arthroplasty. Clin Orthop Relat Res 1989;248:87. [23] Leone JM, Hanssen AD. Management of infection at the site of a total knee arthroplasty. J Bone Joint Surg Am 2005;87:2335. [24] Donley BG, Matthews LS, Kaufer H. Arthrodesis of the knee with an intramedullary nail. J Bone Joint Surg Am 1991;73(6):907. [25] Bargiotas K, Wohlrab D, Sewecke JJ, Lavinge G, Demeo PJ, Sotereanos NG. Arthrodesis of the knee with a long intramedullary nail following the failure of a total knee arthroplasty as the result of infection. J Bone Joint Surg Am 2006;88(3):553. [26] McQueen DA, Cooke FW, Hahn DL. Knee arthrodesis with the Wichita Fusion Nail: an outcome comparison. Clin Orthop Relat Res 2006;446: 132. [27] White SP, Porteous AJ, Newman JH, Mintowt-Czyz W, Barr V. Arthrodesis of the knee using a custom-made intramedullary coupled device. J Bone Joint Surg Br 2003;85(1):57. [28] Arroyo JS, Garvin KL, Neff JR. Arthrodesis of the knee with a modular titanium intramedullary nail. J Bone Joint Surg Am 1997;79(1):26. [29] Henarejos P, Ginés A, Monllau JC, Puig L, Cáceres E. Fractures above and below a modular nail for knee arthrodesis. A case report. Knee 2005;12(3): 231. [30] Goldberg JA, Drummond RP, Bruce WJ, Viglione W, Lennon WP. Huckstep nail arthrodesis of the knee: salvage for infected total knee replacement. Aust N Z J Surg 1989;59(2):147. [31] Bose WJ, Gearen PF, Randall JC, Petty W. Long-term outcome of 42 knees with chronic infection after total knee arthroplasty. Clin Orthop Relat Res 1995;319:285. [32] Brooker Jr AF, Hansen Jr NM. The biplane frame: modified compression arthrodesis of the knee. Clin Orthop Relat Res 1981;160:163. [33] Hernadez-Vaquero D, Suarez-Vazquez A. Knee arthrodesis with navigation: a new indication for computer assisted surgery? A case report. Knee 2007;14(2):162. [34] Knutson K, Bodelind B, Lidgren L. Stability of external fixators used for knee arthrodesis after failed knee arthroplasty. Clin Orthop Relat Res 1984;186:90. [35] Gunes T, Sen C, Erdem M. Knee arthrodesis using circular external fixator in the treatment of infected knee prosthesis: case report. Knee Surg Sports Traumatol Arthrosc 2005;13(4):329. [36] Oostenbroek HJ, Roermund PM. Arthrodesis of the knee after an infected arthroplasty using the Ilizarov method. J Bone Joint Surg Br 2001;83(1): 50. [37] Manzotti A, Pullen C, Deromedis B, Catagni MA. Knee arthrodesis after infected total knee arthroplasty using the Ilizarov method. Clin Orthop Relat Res 2001;389:143. [38] Pritchett JW, Mallin BA, Matthews AC. Knee arthrodesis with a tensionband plate. J Bone Joint Surg Am 1988;70(2):285. [39] Munzinger U, Knessl J, Gschwend N. Arthrodesis following knee arthroplasty. Orthopaed 1987;16(4):301. [40] Nichols SJ, Landon GC, Tullos HS. Arthrodesis with dual plates after failed total knee arthroplasty. J Bone Joint Surg Am 1991;73(7):1020. [41] Kuo AC, Meehan JP, Lee M. Knee fusion using dual platings with the locking compression plate. J Arthroplasty 2005;20(6):772. [42] Christie MJ, DeBoer DK, McQueen DA, Cooke FW, Hahn DL. Salvage procedures for failed total knee arthroplasty. J Bone Joint Surg Am 2003;85-A(Suppl 1):S58.
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[43] Clatworthy MG, Ballance J, Brick GW, Chandler HP, Gross AE. The use of structural allograft for uncontained defects in revision total knee arthroplasty. A minimum five-year review. J Bone Joint Surg Am 2001; 83-A(3):404. [44] Nelson CL, Lonner JH, Rand JA, lotke PA. Strategies of stem fixation and the role of supplemental bone graft in revision total knee arthroplasty. J Bone Joint Surg Am 2003;85:52. [45] Cohen R. A porous tantalum trabecular metal: basic science. Am J Orthop 2002;31(4):216. [46] Gupta A, Meswania J, Blunn G, Cannon SR, Briggs TW. Stanmore noninvasive growing arthrodesis endoprosthesis in the reconstruction of complicated total knee arthroplasty: a case report. Knee 2006;13(3):247.
[47] Voss FR. A new technique of limb salvage after infected revision total knee arthroplasty: artificial fusion. J Arthroplasty 2001;16(4):524. [48] Falahee MH, Matthews LS, Kaufer H. Resection arthroplasty as a salvage procedure for a knee with infection after a total arthroplasty. J Bone Joint Surg Am 1987;69(7):1013. [49] Isiklar ZU, Landon GC, Tullos HS. Amputation after failed total knee arthroplasty. Clin Orthop Relat Res 1994;299:173. [50] Hanssen AD, Trousdale RT, Osmon DR. Patient outcome with reinfection following reimplantation for the infected total knee arthroplasty. Clin Orthop Relat Res 1995;321:55.
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Review
Knee arthrodesis—A review H.S. Somayaji a,b,d,e,⁎, P. Tsaggerides a,d , H.E. Ware c,f , G.S.E. Dowd a,d a
f
Royal Free Hospital, Pond Street, London NW3 2QG, UK b NMC Speciality Hospital, Abu Dhabi, UAE c Chase Farm Hospital, London UK d Department of Orthopaedics, Royal Free Hospital, Pond Street, London NW3 2QG, UK e Department of Orthopaedics, NMC Speciality Hospital, Abu Dhabi, UAE Department of Orthopaedics, Chase Farm Hospital, The Ridgeway, Enfield, Middlesex, London EN2 8JL, UK Received 4 October 2007; received in revised form 18 March 2008; accepted 19 March 2008
Abstract Knee arthrodesis as a primary treatment method for knee arthritis has re-emerged as a salvage procedure for failed knee arthroplasty. This article is an overview of indications, contraindications, principles, preoperative preparation and surgical techniques of knee arthrodesis. Their advantages and disadvantages are discussed together with results and complications. An attempt has also been made to incorporate technical considerations, the author's preferred surgical techniques and indications for the various methods of arthrodesis. © 2008 Elsevier B.V. All rights reserved. Keywords: Arthrodesis; Knee arthroplasty; Intramedullary nail; External fixator; Bone loss
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Introduction . . . . . . . . . . . . . Indications . . . . . . . . . . . . . Contraindications . . . . . . . . . . Preoperative preparation . . . . . . Technical considerations . . . . . . 5.1. Energy expenditure . . . . . 5.2. Ideal alignment . . . . . . . 5.3. One or two stage procedure . 5.4. End point of arthrodesis . . . 5.5. Methods of fixation . . . . . Intramedullary fixation . . . . . . . 6.1. Long nail . . . . . . . . . . 6.2. Modular nail. . . . . . . . . 6.3. Non-modular nail . . . . . . 6.4. External fixation . . . . . . . 6.5. Monoplanar fixators . . . . . 6.6. Biplanar fixators . . . . . . . 6.7. Circular frames . . . . . . . 6.8. Compression plating . . . . . 6.9. Vascularised fibular graft . .
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⁎ Corresponding author. Department of Orthopaedics, Royal Free Hospital, Pond Street, London NW3 2QG, UK. Tel.: +44 7732715505. E-mail addresses: [email protected], [email protected] (H.S. Somayaji). 0968-0160/$ - see front matter © 2008 Elsevier B.V. All rights reserved. doi:10.1016/j.knee.2008.03.005
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6.10. Authors preferred technique. 6.11. Newer prosthetic options . . 6.12. Alternate treatment options . Conflict of interest statement . . . . . . References . . . . . . . . . . . . . . . .
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1. Introduction Total knee replacement is an established and highly successful surgical procedure. However as the indications for primary knee replacements are increasing, so are the complications associated with them. Management of an infected total knee replacement is a universal problem faced by the orthopaedic surgeon. Nelson and Evarts [1] first described knee arthrodesis as a treatment option for failed knee arthroplasty in 1971. The irretrievably failed total knee replacement (TKR) is the main indication for knee arthrodesis at present. When successful, arthrodesis is effective in relieving pain, restoring stability and improving patient function and mobility. 2. Indications Like many reconstructive procedures, arthrodesis of the knee has undergone an evolution in both indications and techniques. In the late 19th and early 20th centuries, knee arthrodesis was the primary treatment for septic arthritis, tuberculosis and poliomyelitis [2–5]. It was also one of the mainstays of treating osteoarthritis and rheumatoid arthritis. Improved anti-tubercular medications have significantly reduced the involvement of knee joint with tuberculosis. Global vaccination programmes have tackled the problems associated with poliomyelitis. In addition excellent results achieved by modern knee arthroplasty surgery have replaced arthrodesis as the treatment option for osteoarthritis and rheumatoid arthritis. At present failed total knee replacement mainly due to infection is the most common indication for knee fusion [5]. The general indications for arthrodesis for an infected total knee replacement are the presence of resistant organisms, an immune compromised patient, gross instability, inadequate skin and soft tissue coverage, deficient extensor mechanism or where the patient is unwilling to consider a revision arthroplasty [5–8]. 3. Contraindications Contraindications for knee arthrodesis include contralateral knee amputation and presence of advanced degenerative changes in the ipsilateral hip or ankle [5,6]. Presence of arthrodesis of the contralateral hip or knee is a relative contraindication. Successful knee fusion is associated with compensatory mechanisms in the spine, hip and ankle. These are an increase in pelvic tilt, hip abduction and ankle dorsiflexion on the ipsilateral side. As a result, the degenerative changes in the ipsilateral hip or ankle affect the compensatory mechanisms and result in poor ambulation and increased energy expenditure [5]. Patients with severe degenerative changes in the spine are also poor candidates for
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knee fusion as compensatory mechanisms lead to increased forces on the lumbar spine resulting in worsening of the spinal problem. 4. Preoperative preparation Extensive preoperative preparation is essential to achieve overall success with the knee fusion. This includes assessment of systemic problems such as immuno-suppressive medication, diabetes mellitus, renal failure, liver disease, peripheral vascular disease, cardiac problems, chronic obstructive pulmonary disease etc. This is not only to optimise their health prior to anaesthesia and surgery but also to prepare them for increased energy expenditure required after knee fusion. Doppler assessment of the peripheral pulses, assessment of capillary refill, local neurological status, status of the overlying skin and soft tissues are crucial as in the case of any knee surgery. It is likely that patients requiring arthrodesis would have had multiple previous surgeries with multiple incisions. Careful assessment of all the scars is important. It is highly advisable to obtain advice from the plastic surgeon regarding placement of an appropriate incision. As most of the blood supply to the skin overlying the knee comes from the perforating vessels on the medial side, any further medial incisions should be avoided [6,9]. Assessment of the knee joint itself consists of alignment, fixed deformities, range of movement, extensor lag as well as ligamentous stability. Careful assessment of the function of the ipsilateral and contralateral hip joints, ipsilateral ankle, contralateral knee as well as examination of the spine is mandatory. Radiological investigations consist of standing anteroposterior view and a lateral view including long-leg films to assess alignment and limb length discrepancy. It is imperative to obtain all the previous surgical details as some of the implants in failed knee replacement may need special extraction devices. The use of a cylinder cast or a knee brace locked in extension during the preoperative period enables the patient to understand their post knee fusion status particularly with regards to ambulation and other day to day activities [6]. 5. Technical considerations 5.1. Energy expenditure Experimental studies have shown that energy required to walk with an arthrodesed knee is about 30% higher than that required for normal walking. The energy required to walk with an above-knee amputation is about 25% greater than that required with an arthrodesed knee. Patients with a knee arthrodesis use 0.16 mL/kg/min oxygen compared to 0.20 mL/kg/min following an above-knee amputation [5,10].
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5.2. Ideal alignment The application of sound fracture management principles will result in a better outcome at any attempted knee fusion. Success depends on achieving good bony contact, preservation of vascularity and rigid fixation. The aim should be to attain an overall limb alignment with the knee in 5–7° of valgus and 15 ± 5° of flexion [5,6,11]. Knee arthroplasty cutting instrumentation may facilitate such a position but their usefulness in the presence of extensive bone loss is limited. Although anterior bow of a long intramedullary nail can provide slight flexion, such a device requires the position of near full extension. The ideal position of flexion and valgus can however be achieved with modular nailing, external fixation and plating techniques [12–14]. It is imperative that minimal bony resection is undertaken to maintain leg length. Bone loss at the time of surgery can be classified according to the system proposed by Klinger et al. [15]. 1. Mild—full bony contact possible. 2. Moderate—incomplete bony contact. 3. Severe—minimal or no bony contact. If there is severe bone loss, additional bone grafting procedures including vascularised fibular graft or allograft techniques should be considered. Application of ring fixators is another option. 5.3. One or two stage procedure
projections [15,18]. After union is achieved overall alignment of the limb should be measured using long-leg films (Fig. 1). 5.5. Methods of fixation The success rate of arthrodesis depends on the method, surgical technique and host factors. Massive bony defects, vascular insufficiency and inadequate soft tissue envelope may compromise any situation. Options for fixation of a knee arthrodesis include external fixators of various configurations, long or short intramedullary nails and internal fixation with plates or combination of implants. Supplemental bone graft should follow the principles of general infection management. The application of graft is not recommended in acutely infected sites [5–8]. Autograft and allograft have been used to supplement large defects in many cases. A vascularised fibular graft has been used successfully in a small number of patients in conjunction with internal fixation [19,20]. 6. Intramedullary fixation Intramedullary devices can either be long nails or short nails of modular and nonmodular types. Rigid fixation, early mobilisation and shorter times to achieve fusion have been reported to be the advantages of intramedullary nailing [21,22]. Additional advantages of intramedullary fixation are lower reported rates of major complications such as recurrent infection, wound breakdown, failure of hardware and the need for additional bone grafting. The complication rate after knee arthrodesis using other methods has been as high as 85% [21].
Knee arthrodesis in cases of infection can be performed either as a single stage or as a two stage procedure. A single stage arthrodesis consists of adequate debridement of any infected tissue and insertion of a fixation device. Following prior surgical procedures resulting in a failed and infected arthroplasty, knee arthrodesis should ideally be attempted as a two stage procedure [16]. The first stage consists of surgical debridement, removal of components and insertion of an antibiotic impregnated cement spacer. This is followed by 6– 8 weeks of antibiotic treatment based on microbiology results from the tissues and serial estimation of inflammatory markers. Antibiotics are then discontinued for about two weeks and inflammatory markers are rechecked. Second stage of arthrodesis is subsequently carried out using the chosen mode of fixation. Several authors have demonstrated that one stage arthrodesis using an intramedullary nailing is safe and effective and not associated with recurrent infection in the absence of virulent organisms, polymicrobial infection or gram negative organisms [11,17]. External fixators, particularly ring fixators are more appropriate in such adverse situations [5,6,13,14]. 5.4. End point of arthrodesis Arthrodesis is considered to be successful when bony trabeculae traverse from tibia to femur in at least two radiographic
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Fig. 1. 4 months post-operative radiograph.
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Wilde and Stearns [22] in their series described a mean time to fusion of 6.6 months using an intramedullary nail. The mean time to fusion following nailing in the study by Waldman et al. [16] was 6.3 months with no patient requiring more than 11 months achieving fusion. Intramedullary nailing has numerous potential disadvantages. The surgical technique is challenging and requires extensive exposure of the joint. Care must be taken to assure maximum bony contact between the two bony surfaces. Shortening of the limb is of concern. However, structural bone graft or an artificial spacer can be placed if significant shortening is anticipated [23]. Recurrence of infection is always a danger. It can present itself as persistent pain in spite of successful union achieved during arthrodesis. The presence of an implant in the intramedullary canal would pose special problems if the infection recurred. An infected nail can be removed by making a large anterior cortical window and removing it in segments using a high speed drill. An additional potential problem is the lack of compression applied at the time of nailing. Although weight bearing does provide some compression, the nail may not achieve the compression force that a dynamic compression plate or an external fixator can provide. However, the reasonable time to fusion observed in the various reports suggest that adequate compression is probably achieved [5,6]. Migration of the nail has been reported. Donley et al. [24] reported this complication in their series of twenty patients treated with an intramedullary nail introduced through the pyriform fossa. In their study, twelve patients had the nail secured proximally and eight did not. Two of the eight unsecured nails migrated proximally necessitating removal of the nail. A secure fit between the intramedullary canal and the nail in addition to the proximal flutes helps to prevent migration. Proximal migration can also be prevented by using the locking mechanism. 6.1. Long nail Use of a long intramedullary nail inserted via pyriform fossa approach is a technically demanding procedure. This is accomplished by inserting a nail in an antegrade fashion down the length of femur passing through the knee joint up to the distal third of tibia [24,25]. Another technique is to pass the nail in a retrograde manner from the knee joint through the femur out of the buttock region followed by its antegrade insertion down the tibia. Both these techniques require prolonged operating time and are associated with increased blood loss [5,6,11,17]. Other potential complications include problems with sterilisation, migration of the nail, breakage, neurovascular injury, intraoperative fractures of the femur or tibia, delayed or nonunion and gluteal pain [11,17]. Contraindications for such devices include the presence of an ipsilateral total hip replacement, gross deformity of the femur or tibia or the presence of active infection [5]. Puranen et al. [11] in their series of 33 patients with knee fusion by a long intramedullary nail, reported union in 87% of patients. Fifteen of the procedures were done for a failed knee arthroplasty; eight had failed because of infection and seven because of aseptic loosening. Twenty-nine of the thirty-three
knees united 3 to 4 months after the first attempt at arthrodesis and three united after technical errors were corrected. One attempt at arthrodesis resulted in a broken nail and nonunion. The functional results were satisfactory in all patients. In a recent report, Bargiotas et al. [25] reviewed the outcome of a staged approach for arthrodesis of the knee with a long curved intramedullary nail after the failure of a total knee arthroplasty due to infection. They reported the results for twelve patients who underwent knee arthrodesis after an average follow up of 4.1 years. Solid union was achieved in 10 of the 12 knees. The average time to union was 5.5 months. The average limblength discrepancy was 5.5 cm. The mean WOMAC score improved from 41 to 64 points. They recommend an arthrodesis with the technique involving convex-to-concave preparation of bone ends to provide a painless functional gait with low complication and re-operation rates. 6.2. Modular nail A modular system is attractive as a fusion device. In contrast to a one-piece intramedullary nail, the modular system has two components with a stable coupler, which allows for a more accurate fit of the nail in the intramedullary canal by accommodation of the nail to the contour of the femoral shaft, thus reducing the risk of fracture during insertion. Intramedullary fixation with this device has the advantage of allowing debridement of the knee followed by insertion of the nail using one of the previous knee incisions. This avoids the need for making a surgical approach to the pyriform fossa as required with an antegrade nail. It also allows for an alteration in size between the intramedullary canals of the femur and tibia and to obtain correct alignment [26,27]. Bone loss can be addressed with a metal or polyethylene spacer or bone grafting. One of the key advantages of such devices is the ability to allow immediate full weightbearing which allows compression across the arthrodesis site resulting in faster fusion. White et al. [27] reported the use of customised coupled nail (Mayday Arthrodesis Nail) in nine patients of which five were for infected arthroplasty. Union was achieved in all patients (100%) at a mean time of 10 months using the customised implant. There were no complications despite early weightbearing. No further procedures were required. This contrasted with a rate of union of 53% and a complication rate of 76% with alternative techniques. They conclude that a customised coupled intramedullary nail can give excellent stability allowing early weightbearing and results in a high rate of union with minimal postoperative complications. Arroyo et al. [28] reported a 90% success rate in 19 of 21 knees treated with a modular nailing system. Their study included patients who underwent arthrodesis after tumour resection and patients with aseptic loosening following total knee replacement. They reported a mean time to fusion of 8.4 months and an overall satisfaction rate of 94%. Hinarejos et al. [29] reported a case of femoral and tibial fractures at each end of a modular nail in a solidly fused knee 8 months after an arthrodesis. They had to remove the Wichita fusion nail used for arthrodesis via the femoral fracture site and
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use a custom made femoro-tibial interlocking nail as a definitive treatment. 6.3. Non-modular nail Lai et al. [17] reported the results of their series involving 33 patients where arthrodesis was attempted using a short nonmodular Huckstep nail after failure of a non-constrained total knee arthroplasty. Three knees had earlier failed attempts at arthrodesis using external fixation. The Huckstep nail was inserted through the knee, retrograde into the femur, and then antegrade into the tibia. Local bone graft was used in all knees. After an average follow up of 47 months, 91% of their patients had radiological signs of union. The average time to union was 5.2 months. In their series of 17 patients, Goldberg et al. [30] achieved fusion in 13 patients using Huckstep nail for failed knee arthroplasty. Their technique involved using a long Huckstep nail in an antegrade manner similar to the use of a long straight Kuntscher nail, which was the original technique described by Huckstep. 6.4. External fixation A knee arthrodesis can be achieved in an infected total knee arthroplasty using an external fixator. They can be of monolateral monoplanar, bilateral monoplanar, monolateral biplanar, bilateral biplanar or multiplanar types [31,32]. In addition, circular frames such as Ilizarov as well hybrid fixator frames have been used in achieving knee arthrodesis. The use of wireless computer navigation system in achieving knee arthrodesis using external fixators has also been reported [33]. 6.5. Monoplanar fixators External fixators were pioneered as a method of achieving knee arthrodesis by Charnley and Baker [2]. His technique consisted of using two femoral pins, two tibial pins and a Thomas splint to maintain compression at the site of fusion [2,5]. However, this technique was used mainly for the primary treatment of osteoarthritis and infective arthritis. He reported an excellent result which was due to the optimal bony contact between the femoral and tibial segments as well as compression obtained using the external fixation. However, use of monoplanar fixators to achieve fusion in a failed knee arthroplasty has not met with similar success. This is attributed to the minimal stability offered by such devices in the sagittal plane. Hak et al. [18] reported failure of 9 monoplanar fixators in achieving fusion in 19 patients. 6.6. Biplanar fixators This system consists of transfixation pins in the femur and tibia as well as additional pins placed anteriorly. Compared to uniplanar fixators, biplanar fixators provide optimal mediolateral stability [31]. Knutson et al. [34] reported that fixator configuration with sagittal pins connected to an anterior fixator provide the greatest
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stiffness. They also reported increased stability and better fusion rates compared to unilateral fixator design. However, Hak et al. [18] reported a similar union rate but higher complication rate in their series of 17 patients who had knee arthrodesis with biplanar external fixators. 6.7. Circular frames Although conventional monoplanar and multiplanar fixators are easier to apply, the poor rate of fusion achieved with such devices and the higher complication rate has resulted in their infrequent use to-date. Application of circular frames requires considerable surgical skill to obtain stable compression with good alignment. However, they offer potential advantages. The main advantages of Ilizarov method are the ability to provide a mechanical stimulus for bone formation, to provide rigid fixation and vary the rigidity during treatment, to modify alignment of the arthrodesis using hinges and to perform a simultaneous limb lengthening [21,35–37]. In addition, their use has no risk of intramedullary dissemination of the infection and allows easy removal of the hardware. The disadvantages of arthrodesis and subsequent bone transport using the Ilizarov technique include pin loosening, pin site infection, delayed weightbearing, delayed fusion and the inconvenience associated with a long treatment period. In their study, Manjotti et al. [37] reported the fusion rate to be 100% using Ilizarov frames to achieve knee fusion. Despite studies showing a need for bone grafting in 5% to 42% of patients in some series treated with an external fixator, no patient in their study required bone grafting to achieve union. Arthrodesis was achieved after a mean duration of 6.8 months, which is consistent with that found in other studies using external fixation or an intramedullary nail. The problem of delayed weightbearing was addressed by modifying the technique to use half-pins. In the patients in whom half-pins were used, full weightbearing was allowed immediately after surgery. Oostenbroek et al. [36] reported their experience of using the Ilizarov technique in 15 patients, achieving a rate of union of the arthrodesis of 93%. They reported that 53% of these patients had undergone earlier attempts at arthrodesis and most had long-standing osteomyelitis and were elderly. The rate of complications related to their treatment was 80%. In their experience many complications were related to poor quality and quantity of available bone. The mean total duration of treatment with their technique was 51 weeks. They also reported that when the arthrodesis was performed under adverse clinical conditions, for example where the infection was difficult to control, the treatment time was more than a year. An Ilizarov arthrodesis has the advantage that it can be performed in the presence of active infection. The infection subsides with continuous axial compression and treatment with antibiotics, with the arthrodesis proceeding to union [36]. 6.8. Compression plating Use of one or two plates after preparing the femoral and tibial segments for arthrodesis has also been attempted [38–40].
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Advantages of this technique include combining debridement and implantation with the same incision and the ability to achieve compression at the site of arthrodesis. In the series published by Pritchett et al. [38], 26 patients had an arthrodesis of the knee using a single anterior tension band compression plate of which six were for failed knee arthroplasties. After a minimum of 2 year follow-up period solid osseous union occurred in all patients. Munzinger et al. [39] achieved successful union in 27 of 34 knees with the use of a single large laterally applied plate. Nichols et al. [40] used a dual plating technique where dynamic compression plates were applied on the medial and lateral sides. All 11 patients achieved union at a mean duration of 5.6 months. Kuo et al. [41] reported the use of a dual locking compression plating technique to achieve fusion in three patients who had failed infected non-reconstructable total knee arthroplasties with 100% success rate. It is important to note that these patients were kept non-weightbearing in a long-leg cast for 3 months followed by a hinged knee brace locked in extension. Weightbearing was gradually allowed to full over 1 month period. 6.9. Vascularised fibular graft It is not uncommon to encounter the problem of large osseous defects in the knee following multiple attempts at reconstructive surgery. Conventional methods of achieving arthrodesis are unlikely to result in successful outcome as gross shortening of the extremity or nonunion are more likely. Use of vascularised ipsilateral fibular graft in addition to an intramedullary fixation device is an option [19,20]. The repair process is likely to be more rapid and the strength and stiffness are likely to be superior to the joints which have been treated with an autogenous non-vascularised graft (iliac crest bone graft). These procedures are technically demanding and should be performed in conjunction with a microvascular surgeon. In a study published by Rasmussen et al. [19], 12 of the 13 patients achieved fusion after an average follow up of 51 months. The other patient who had multiple previous reconstructive attempts required an amputation. The average duration of surgery was 8.5 h and average blood loss was 2322 mL. Usui et al. [20] in their series of 17 patients achieved successful union in 16 patients using vascularised fibular graft. Use of allograft and sliding femoral and tibial grafts are also the other means of filling any large bony defects [6]. 6.10. Authors preferred technique We prefer the modular nailing system (Mayday arthrodesis nail—(Orthodesign, Christchurch, UK) for achieving knee arthrodesis in our units. This is a two part nail, where both components are inserted via a single knee incision often through the original incision from previous knee surgery. Subsequently two components are joined by a single antero-posterior locking pin to form a solid nail. The tibial component is locked by means of a targeting device, whilst the femoral component is
unlocked to facilitate compression with early weightbearing. However patients are discouraged from applying excessive rotational forces on the components and a knee brace is used for 3 weeks to assist compliance. Each nail is customised to suit individual patient's anatomy. The femoral component is designed to be stable in rotation although supplementary locking remains an option. 6.11. Newer prosthetic options It is imperative to carefully analyse an unsuccessful TKR to accurately determine the reason for failure. Once this has been done, it is necessary to determine, on a case-by-case basis, whether revision surgery is reasonable. A team approach is often useful for this process and may involve advice from the physicians, anaesthetic team, plastic surgeons, vascular surgeons, microbiologist and inputs from the patient and family. Availability of new prosthetic materials allows the surgeon to consider reconstruction rather than amputation or resection if encountered with severe bony or soft-tissue defects [42]. Developments in tumour surgery have also contributed to the reconstructive efforts in failed knee replacement surgery. Structural allograft composites, custom prostheses fabricated from porous tantalum or massive prostheses can address some of the problems associated with extensive bone loss. Structural allograft composites have shown satisfactory intermediate-term results, but long-term results are still awaited [42–44]. The introduction of porous tantalum offers another option for the reconstruction of bony defects. Identical cell structure to cancellous bone, availability in complex shapes, fatigue resistance, excellent frictional characteristics and long term stability are some of the key advantages of this material [45]. Gupta et al. [46] have reported the use of a non-invasive growing endoprosthesis to achieve limb length equality and pain free walking in one of their patient who had a failed complicated second revision knee arthroplasty. However it is important to note that none of the available treatments absolutely rule out the possibility of recurrent infections in the limb. 6.12. Alternate treatment options The other alternatives to arthrodesis are chronic antibiotic suppression, artificial arthrodesis, resection arthroplasty and amputation. Antibiotic suppression is usually not effective with an overall success rate of about 27% [5,6,47]. Voss in 2001[47] reported the new concept of artificial arthrodesis in the management of severely infected knee arthroplasty. It consists of inserting a long intramedullary nail through a large cement spacer in the knee and to allow immediate full weightbearing. Amputation or resection arthroplasty should be considered in cases of life-threatening infection, persistent infection, irreparable soft-tissue deficiency, extensive bone loss and the wishes of the patient following multiple failed attempts at reconstructive surgery. Resection arthroplasty is best tolerated by low
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demand patients who are already disabled because of multiple joint involvements [48]. The prevalence of amputation following total knee arthroplasty ranges from 0.02% to 0.18%, but it can be as high as 6% in patients with a chronic infection at the site of a total knee replacement [40,49]. Isiklar et al. [49], in a study of amputation following total knee replacement, found that patients had undergone an average of six surgical procedures prior to having an amputation. In a series of patients who had a repeated infection following insertion of revision components for an infection at the site of a total knee replacement, Hansen et al. [50] found that patients had undergone an average of thirteen surgical procedures. Conflict of interest statement This is to confirm that we have not received any outside funding or grants in support of our research or preparation of the manuscript. We or a member of our immediate family, have not received from any commercial entity any payments or any pecuniary, in kind, or other professional or personal benefits any commitment or agreement to provide such Benefits that were related in any way to the subject of the work or the research that we conducted in connection with the work. References [1] Nelson CL, Evarts CM. Arthroplasty and arthrodesis of the knee joint. Orthop Clin North Am 1971;2(1):245. [2] Charnley J, Baker SL. Compression arthrodesis of the knee: a clinical and histological study. J Bone Joint Surg Br 1952;34-B(2):187. [3] Hibbs RA. The treatment of tuberculosis of the joints of the lower extremities by operative fusion. J Bone Joint Surg 1930;12:749. [4] Soto-Hall R. Fusion in charcots disease of the knee: new technique for arthrodesis. Ann Surg 1938;108:124. [5] Conway JD, Mont MA, Bezwada HP. Arthrodesis of the knee. J Bone Joint Surg Am 2004;86-A(4):835. [6] MacDonald JH, Agarwal S, Lorei MP, Johanson NA, Freiberg AA. Knee arthrodesis. J Am Acad Orthop Surg 2006;14(3):154. [7] Vlasak R, Gearen PF, Petty W. Knee arthrodesis in the treatment of failed total knee replacement. Clin Orthop Relat Res 1995;321:138. [8] Windsor RE. Knee arthrodesis. Surgery of the knee. New York, NY: Churchill Livingstone; 1993. p. 1103. [9] Vince KG. Revision knee arthroplasty technique. Inst Course Lect 1993;4242:325. [10] Waters RL, Perry J, Antonelli D, Hislop H. Energy cost of walking of amputees: the influence of level of amputation. J Bone Joint Surg Am 1976;58(1):42. [11] Puranen J, Kortelainen P, Jalovaara P. Arthrodesis of the knee with intramedullary nail fixation. J Bone Joint Surg Am 1990;72(3):433. [12] Incavo SJ, Lilly JW, Bartlett CS, Churchill DL. Arthrodesis of the knee: experience with intramedullary nailing. J Arthroplasty 2000;15(7):871. [13] Salem KH, Keppler P, Kinzl L, Schmelz A. Hybrid external fixation for arthrodesis in knee sepsis. Clin Orthop Relat Res 2006;451:113. [14] Wiedel JD. Salvage of infected total knee fusion: the last option. Clin Orthop Relat Res 2002;404:139. [15] Klinger HM, Spahn G, Schultz W, Baums MH. Arthrodesis of the knee after failed infected total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc 2006;14(5):447. [16] Waldman BJ, Mont MA, Payman KR, Freiberg AA, Windsor RE, Sculco TP, et al. Infected total knee arthroplasty treated with arthrodesis using a modular nail. Clin Orthop Relat Res 1999;367:230.
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