phantom5815 |
05-11-2006 12:31 PM |
Not very common for anyone under 30 to get a TKR he may nad one of these alternatives ( sorry but I haven't had time to track down a more current article. This is from 2000-2002): <BR><a href="http://www.medscape.com/viewarticle/420498" target="_blank">http://www.medscape.com/viewarticle/420498</a> <BR><i>Alternatives to Total Knee Arthroplasty <BR>William P. Barrett, MD <BR> <BR>Introduction <BR> <BR>Total knee arthroplasty (TKA) is a proven treatment for patients with arthritis of the knee, with 90% to 95% success at 15-year follow-up. However, in certain situations, there may be alternative treatments that also benefit the patient. Still, the role of these alternative procedures, such as arthroscopic debridement, proximal tibial osteotomy, unicompartmental replacement, and biologic resurfacing of the knee, continues to be debated. At the Contemporary Techniques and Issues of Orthopedics meeting, held in Coeur d'Alene, Idaho, September 14-16, 2000, a panel including the author of this summary discussed these alternative procedures. <BR> <BR>Arthroscopy <BR>The use of arthroscopy in the treatment of the arthritic knee remains controversial. It is thought that removal of inflammatory mediators (interleukins, metalloproteinases), degenerative cartilage, and meniscal fragments results in better function and less pain, at least in the short term. It is not clear whether these effects have long-term therapeutic benefit. <BR> <BR>Generally, the clinical and radiographic presentations associated with good outcomes following arthroscopy include: <BR> <BR> * short duration of symptoms <BR> <BR> * mechanical symptoms such as locking or catching <BR> <BR> * -x-ray films revealing loose bodies <BR> <BR> * minimal angular deformity, and <BR> <BR> * preservation of joint space. <BR> <BR>The following factors are generally associated with poor outcomes: <BR> <BR> * symptoms of chronic pain, lack of mechanical symptoms, and significant ligamentous laxity apparent on examination, and <BR> <BR> * x-ray films revealing significant angular deformity or loss of joint space, chondrocalcinosis, and multiple-compartment disease <BR> <BR>Several procedures can be performed arthroscopically on the degenerative knee: <BR> <BR> * partial meniscectomy <BR> <BR> * debridement, and <BR> <BR> * abrasion arthroplasty and microfracture techniques. <BR> <BR>Arthroscopic meniscectomy is beneficial initially, but results deteriorate with time. At 30-month follow-up, Jackson[1] reported 95% good or excellent results if no degenerative changes were noted at surgery and 80% good or excellent results if degenerative changes were present. In 131 knees treated with partial meniscectomy with limited debridement, Rand[2] found that there was 80% improvement in function after 1 year, but this fell to 67% after 5 years. <BR> <BR>In a series of 49 knees in 44 patients, two thirds of whom had severe arthritis, Baumgaertner and colleagues[3] found that 39% did not benefit from arthroscopic debridement. Nine percent did have temporary improvement (averaging 15 months) and good or excellent results were found in 52% of patients. This declined to 40% of patients at the end of follow-up, which averaged 33 months. Arthroscopic debridement--including removal of mechanical irritants such as chondral flap tears, degenerative meniscal tears, and hypertrophic synovium--has yielded an average 66% improvement in overall function.[2, 4] Factors associated with poor long term results are increasing age, severity of disease, and malalignment of the knee. <BR> <BR>Abrasion arthroplasty and microfracture techniques, which are based on the assumption that drilling eburnated bone stimulates reparative cartilage formation, have not produced consistent results. Rand[2] followed 28 patients that underwent debridement with abrasion arthroplasty and found that 11 patients were improved, 8 were unchanged, and 9 were worse. Fifty percent of these patients underwent TKA at a mean of 3 years after the abrasion procedure. <BR> <BR>It is unclear whether continuous passive motion and protected weight bearing following these procedures are beneficial. Arthroscopic treatment of the arthritic knee yields the best results in the patient with recent onset of mechanical symptoms, mild degenerative changes, and minimal angular deformity. <BR> <BR>Tibial Osteotomy <BR>The use of high tibial osteotomy has decreased in recent years due to the success of TKA. However, studies evaluating high tibial osteotomy continue to demonstrate good outcomes. Rinonapoli and colleagues[5] found that 80% to 90% of patients had good results at 2-year follow-up; this decreased to 50% to 60% good results at 10-year follow-up and this percentage declined even further after 15 years.[5] In a group of patients younger than 50 years at the time of osteotomy, with preoperative range of motion greater than 120°, Naudie and colleagues[6] found 95% good results at 2-year follow-up and 80% good results at 10-year follow-up. <BR> <BR>Good outcomes have been associated with more rather than less correction, internal fixation, early range of motion, and younger age. Poor outcomes are associated with undercorrection, workers' compensation, and minimal preoperative varus deformity. <BR> <BR>The goal of tibial osteotomy is anatomic (tibiofemoral) alignment of 7° to 10° valgus or a mechanical axis passing through 30% to 40% of the lateral tibial plateau. Stable fixation, which allows early range of motion and weight bearing should be obtained. A midline incision, which can be used for subsequent conversion to TKA, is preferable. The procedure can be performed using either a closing lateral osteotomy, which is most common, or an opening medial osteotomy. <BR> <BR>The indications for tibial osteotomy include the following: <BR> <BR> * a young patient (less than 50 years of age) with a vigorous lifestyle or a job that involves heavy labor <BR> <BR> * primarily medial compartment pain <BR> <BR> * varus malalignment of the knee <BR> <BR> * relative preservation of the lateral compartment and patellofemoral joint. <BR> <BR>The procedure is contraindicated in patients with flexion contractures greater than 15° or suffering from inflammatory arthritis. <BR> <BR>Unicompartmental Arthroplasty <BR>The utility of unicompartmental knee replacement is controversial, although the procedure is very popular in Europe and is showing increased popularity in the United States due to the advent of minimally invasive techniques. Pain relief with unicompartmental replacement is similar to that of TKA, and range of motion is improved over TKA. However, the failure rate, due to polyethylene wear, progression of disease in the opposite compartment, and loosening of implants, is higher than what is found in comparable TKA series.[7] This has resulted in the limited role of unicompartmental replacement in the United States. Long-term results are not available, requiring close follow-up of patients who undergo the procedure.[8] <BR> <BR>The indications for unicompartmental replacement include the elderly patient with the following: <BR> <BR> * unicompartmental disease <BR> <BR> * a sedentary lifestyle <BR> <BR> * fixed flexion contracture less than 15° <BR> <BR> * an intact anterior cruciate ligament[9] <BR> <BR>Contraindications include the following: <BR> <BR> * inflammatory arthritis <BR> <BR> * obesity <BR> <BR> * significant ligamentous laxity <BR> <BR>The introduction of minimally invasive unicompartmental replacement has allowed its use in younger patients with unicompartmental arthritis, for whom a unicompartmental replacement can serve as the first stage in a series of arthroplasty operations. Dr. Charles Engh, of the Anderson Orthopaedic Research Institute in Alexandria, Virginia, reviewed the challenges of using minimally invasive techniques. They include the following: <BR> <BR> * the difficulty of evaluating the opposite compartment and patellofemoral joint <BR> <BR> * the inability to use intramedullary devices for alignment <BR> <BR> * difficulty balancing soft tissues. <BR> <BR>Minimally invasive techniques require tibial components with shorter pegs and modified cementing techniques due to the limited exposure. Dr. Engh recommended that before surgeons begin performing minimally invasive procedures, they become comfortable with open unicompartmental replacements. <BR> <BR>The basic technique of unicompartmental replacement involves a measured resection technique, with care taken to match implant-to-implant alignment and rotation (Figure 1). Slight undercorrection of deformity is desirable to avoid failure in the opposite compartment. Cemented fixation has yielded better results when compared with cementless fixation. Minimally invasive techniques use shorter incisions and arthrotomies, modified implants, and outpatient or overnight hospital stays. <BR> <BR> Figure 1. Postoperative x-ray film of unicompartmental replacement demonstrating excellent implant-to-implant alignment and slight undercorrection of the varus deformity. <BR> <BR>Biologic Resurfacing <BR>Impact and torsional joint loading can injure articular cartilage, resulting in pain, joint dysfunction and effusions, and, sometimes, progressive joint degeneration. Clinical evaluation of the patient with a cartilage injury includes the following: <BR> <BR> * defining the size, depth, and location of the lesion <BR> <BR> * establishing the origin and pathogenesis of the injury <BR> <BR> * correlating the lesion with symptoms <BR> <BR> * determining where the affected joint is on the cartilage disease continuum <BR> <BR> * evaluating the patients goals and expectations. <BR> <BR>If it is determined that the patient would benefit from biologic resurfacing, there are several options: <BR> <BR> * microfracture <BR> <BR> * autologous osteochondral transplantation <BR> <BR> * autologous chondrocyte transplantation <BR> <BR> * osteochondral allograft transplantation. <BR> <BR>Successful biologic resurfacing is dependent on the following factors: <BR> <BR> * lesions less than 4 cm2 <BR> <BR> * treatment within 3 months of injury <BR> <BR> * postoperative protected weight bearing for 6 weeks following surgery <BR> <BR> * the use of continuous passive motion. <BR> <BR>Microfracture is thought to stimulate tissue regeneration by making drill holes in the subchondral bone. Clinical follow-up of 235 patients indicates that at 3-5 years, 75% of the patients were improved, 20% unchanged, and 5% worse.[10] <BR> <BR>Osteochondral autologous transfer (mosaicplasty) demonstrates better results than abrasion arthroplasty, with a higher percentage of patients able to return to sports or work following surgery.[10] Clinical data on 57 patients who underwent mosaicplasty indicated that 91% had good or excellent results at 3 year follow-up. <BR> <BR>Results of autologous chondrocyte implantation (Carticel Genzyme Tissue Repair, Cambridge, Massachusetts) have been good or excellent in 92% of patients with isolated femoral condyle lesions and in 89% of those with osteochondritis dissecans.[11] Poor results were correlated with multiple lesions, patellar lesions, and femoral condylar lesions associated with anterior cruciate ligament deficiency. Peterson and colleagues[11] found an overall 80% improvement (to normal or near-normal function) in a 9-year retrospective review of 101 patients who underwent autologous chondrocyte transplantation. <BR> <BR>Fresh osteochondral allografts have been reserved, at tertiary care centers, for patients with larger lesions involving osteochondral defects, avascular necrosis, or secondary arthrosis. <BR> <BR>The algorithms for cartilage repair depend on the size, depth, and location of the lesion, as well as the biologic and mechanical status of the joint. <BR> <BR>Revision to TKA <BR>Because high tibial osteotomy and unicompartmental arthroplasty are usually done as an intermediary step, easy conversion to TKA should be considered when doing the initial procedure. For example, the results of converting prior proximal tibial osteotomies to TKAs have been generally inferior to primary TKAs. Mont and colleagues,[12] in a review of 73 knees converted from high tibial osteotomy to TKA with an average follow-up of 6.1 years, noted 64% good or excellent results; this was inferior to an age-matched set of primary TKAs. Factors in the study group that led to difficulties with exposure during conversion to TKA were multiple and inappropriate skin incisions and scarring of the extensor mechanism and patella baja. Proximal tibial deformity with elevation of the medial joint line, loss of posterior slope, and retained hardware make placement of the tibial component more difficult; they require careful preoperative templating before the conversion procedure (Figure 2). <BR> <BR> Figure 2: Postoperative x-ray film following high tibial osteotomy demonstrating loss of lateral bone, which makes conversion to total knee arthroplasty more difficult. <BR> <BR>Revision of failed unicompartmental arthroplasty to TKA has also yielded inferior results compared with a series of primary TKAs.[9] The main problem encountered at the time of revision is bone loss of both the tibia and the femur (Figure 3); residual deformity and contracted soft tissues were also noted. Current revision recommendations include attention to balancing the flexion-extension gap, ensuring proper rotation of the femoral component, and treating defects appropriately with either metal augmentation or bone grafting.[13] Conversion to a cruciate-retaining or cruciate-substituting prosthesis is based on surgeon preference (Figure 4). <BR> <BR> Figure 3: Intraoperative photograph demonstrating contained bony defect on femoral and tibial side following removal of failed unicompartmental replacement. <BR> <BR> Figure 4: Postoperative anterior-posterior x-ray film, status post conversion of failed unicompartmental replacement to total knee arthroplasty. <BR> <BR>Conclusion <BR>Although there are several alternatives to TKA for treatment of the patient with arthritis of the knee, they are limited to conditions involving only one compartment of the knee. This narrows the number of indications appropriate for these procedures. When considering the options, a surgeon must consider age, activity, lifestyle, bone quality, deformity, patient expectations, and the likely effects on subsequent procedures. <BR> <BR>References <BR> <BR> 1. Jackson RW. The role of arthroscopy in the management of the arthritic knee. Clin Orthop. 1974;101:28-35. <BR> 2. Rand JA. Role of arthroscopy in osteoarthritis of the knee. Arthroscopy 1991;7:358-363. <BR> 3. Baumgaertner MR, Cannon WD Jr, Vittori JM, et al. Arthroscopic debridement of the arthritic knee. Clin Orthop. 1990;253:197-202. <BR> 4. Harwin SF. Arthroscopic debridement for osteoarthritis of the knee: predictors of patient satisfaction. Arthroscopy. 1999;15:142-146. <BR> 5. Rinonapoli E, Mancini G, Corvaglia A, Musiello S. Tibial osteotomy for varus gonarthrosis: a 10-21 year follow-up study. Clin Orthop. 1998;353:185-193. <BR> 6. Naudie D, Bourne R, Rorabeck C, Bourne T. Survivorship of the high tibial valgus osteotomy: a 10-22 year follow-up study. Clinic Orthop. 1999;367:18-27. <BR> 7. Schai PA, Suh JT, Thornhill TS, Scott RD. Unicompartmental knee arthroplasty in middle-aged patients: a 2-6 year follow-up evaluation. J Arthroplasty. 1998;13:365-372. <BR> 8. Repicci JA, Eberle RW. Minimally invasive surgical technique for unicondylar knee arthroplasty. J South Orthop Assoc. 1999;8:20-27. <BR> 9. Thornhill TS, Scott RD. Unicompartmental total knee arthroplasty. Orthop Clin North Am. 1989;20:245-256 <BR> 10. Orthopaedic knowledge update. In: Pellicci PM, Tria AJ, Garvin KL eds. Hip and Knee Reconstruction. Rosemont, Illinois: American Academy of Orthopaedic Surgeons; 2000. <BR> 11. Peterson L, Minus T, Brittberg M, Nilsson A, Sjogren-Jansson E, Lindahl A. Two to nine-year outcome after autologous chondrocyte transplantation of the knee. Clinic Orthop. 2000;374:212-234. <BR> 12. Mont MA, Antonaides S, Krackow KA, et al. Total knee arthroplasty after failed high tibial osteotomy: a comparison with a matched group. Clin Orthop. 1994;299:125. <BR> 13. Barrett WP, Scott RD. Revision of failed unicondylar unicompartmental knee arthroplasty. J Bone Joint Surg Am. 1987;69:1328-1335. <BR> <BR> <BR> <BR></i><img src="http://www.wakeworld.com/MB/Discus/messages/65919/325645.jpg" alt="Upload">
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