Unicompartmental knee arthroplasty surgery: 10-Year minimum follow-up period

Sixty knees in 54 patients were followed a minimum of 10 years after unicompartmental knee arthroplasty surgery. Follow-up periods ranged from 10 to 18 years (average, 12 years). In all cases, a Marmor prosthesis was used. Two patients required arthroplasty surgery after the 10-year mark. Seven knees required revision prior to 10 years, and the 10- to 12-year survivorship for the entire cohort was 93%. Slight undercorrection of varus alignment and adequate polyethylene thickness of the tibial component appear to be important contributors to a successful outcome.     

Unicompartmental knee arthroplasty

Recent increased interest in less invasive surgical techniques has led to a concurrent resurgence in unicompartmental knee arthroplasty. The procedure has evolved significantly over the past three decades. Proponents of unicompartmental knee arthroplasty cite as advantages lower perioperative morbidity and earlier recovery. Both clinical outcome and kinematic studies have indicated that successful unicompartmental knee arthroplasty functions closer to a normal knee. Recent reports have demonstrated success in expanding the classic indications of unicompartmental knee arthroplasty to younger and heavier patients. Both fixed- and mobile-bearing implants can yield excellent clinical outcomes at >10 years, but with different modes of long-term failure. Proper execution of surgical technique remains critical to optimizing outcome. Long-term studies are needed to appropriately define the role of less invasive unicompartmental surgical approaches as well as the role of computer navigation.     

Unicompartmental knee arthroplasty

Unicondylar knee arthroplasty is an alternative to tibial osteotomy for the treatment of medial or lateral compartment noninflammatory arthritis. It must be considered in the context of the other viable surgical options for treatment of this disorder. Appropriate patient selection and careful surgical technique will provide good to excellent results in over approximately 90% of individuals while preserving bone stock and ligamentous structures for revision if necessary.     

人工膝关节单髁关节置换术研究进展

单髁关节置换术治疗单间室骨关节炎近些年取得很大进展,引起越来越多的关注.文中综述了近年来最新的研究进展.研究表明经严格的病例选择,单髁关节置换术10年生存率达95%左右.术后关节功能好,并发症少,具有损伤小、恢复快、费用低、保存骨量等优点,是治疗单间室关节炎值得考虑的手术选择.     

Unicompartmental knee arthroplasty. Ten- to 13-year follow-up study

In the past decade, two concepts have caused considerable controversy in orthopedic surgery of the knee. Some orthopedic centers contend that osteotomy of the tibia is the procedure of choice for unicompartmental gonarthrosis of the knee and resist the concept of unicompartmental arthroplasty. The other concept is that if unicompartmental arthroplasty is necessary, the entire joint should be replaced, since the uninvolved compartment may develop arthritis in the future. This concept is illogical and contrary to the basic orthopedic principle of preserving normal structures whenever possible. It is obvious that joint replacements may not last the life of the patient and the need for revision must be considered; therefore, the original procedure should preserve as much bone stock as possible. The purposes of this review of unicompartmental replacement are to resolve these questions with data on long-term results of unicompartmental arthroplasty compared with data on high tibial osteotomy, to evaluate the cause of failures, and to improve future results. Eighty-seven consecutive unicompartmental arthroplasties were performed between November 1972 and April 1976. There were 60 knees available for study, with a minimum ten-year (average, 11-year) follow-up period. The results were evaluated using the Hospital for Special Surgery rating system, with 30 excellent, eight good, four fair, and 18 poor results. Seventy percent of the patients had satisfactory results, and pain relief was accomplished in 86.6% of patients. Of the 21 failures, the majority were due to material or technical problems and improper selection of the patients.(ABSTRACT TRUNCATED AT 250 WORDS)     

Polycentric total knee arthroplasty. A ten-year follow-up study

After review of the first 209 polycentric total knee arthroplasties (in 159 patients) performed at the Mayo Clinic between July 1970 and November 1971, we found that the calculated probability of the arthroplasty remaining successful ten years postoperatively was 66 per cent. Actual results showed 42 per cent of the arthroplasties to be successful in patients who were still alive at review; another 24 per cent were successful but were in patients who had died or were lost to follow-up before ten years postoperatively. In 34 per cent failure occurred, which we defined as reoperation for any reason, unacceptable pain, or loss of function. The most common causes of failure were instability or ligament laxity (13 per cent), loosening of a component (7 per cent), infection (3 per cent), and patellofemoral joint pain (4 per cent). Prior knee surgery significantly decreased the probability of success, as did axial malalignment of the prosthetic components at operation.     

Unicompartmental total knee arthroplasty

This article traces the evolution of unicondylar design and examines its indications, common aspects of surgical technique independent of design, results, and complications. The dichotomy of opinion concerning unicompartmental knee arthroplasty may reflect differences in patient selection, prosthesis selection, and surgical technique.     

Modern unicompartmental knee arthroplasty with cement: a three to ten-year follow-up study

BACKGROUND: Unicompartmental arthroplasty is a treatment alternative when only one compartment of the knee is affected with arthritis, but the reported results of this procedure have been variable. The purpose of the present study was to evaluate the results of a modern unicompartmental knee arthroplasty performed with use of a cemented metal-backed prosthesis and surgical instrumentation comparable with that used for total knee replacement. METHODS: The indications for the procedure were osteonecrosis or osteoarthritis associated with full-thickness loss of cartilage that was limited to one tibiofemoral compartment as evaluated on standing and stress radiographs. One hundred and sixty consecutive cemented metal-backed Miller-Galante prostheses in 147 patients were evaluated after a mean duration of follow-up of sixty-six months (range, thirty-six to 112 months). The mean age of the patients at the time of the index procedure was sixty-six years. RESULTS: Three knees were revised because of progression of osteoarthritis in the patellofemoral joint (two knees) or the lateral tibiofemoral compartment (one knee). Two knees had revision of the polyethylene liner. The average Hospital for Special Surgery knee score improved from 59 points preoperatively to 96 points at the time of the review. According to Kaplan-Meier analysis, the ten-year survival rate (with twenty-nine knees at risk) was 94% +/- 3% with revision for any reason or radiographic loosening as the end point. CONCLUSIONS: A modern unicompartmental knee arthroplasty is a valid alternative for patients with unicompartmental tibiofemoral noninflammatory disease. The patient selection must be strict with regard to the status of the patellofemoral joint. The preoperative planning includes stress radiographs to assess the correction of the deformity and the status of the uninvolved compartment. Continued long-term follow-up is necessary to evaluate long-term polyethylene wear.     

Unicompartmental knee arthroplasty following patellectomy

Patients with total knee arthroplasty following patellectomy have been reported to experience pain and instability. The results of ten patients with 11 knee arthroplasties using the Marmor knee were excellent in seven patients and good in three with an average follow-up period of nine years. It is extremely important to preserve the cruciate ligaments or to use a total knee prosthesis that has inherent anteroposterior stability.     

Unicompartmental knee arthroplasty. Eight- to 12-year follow-up evaluation with survivorship analysis

One hundred consecutive unicondylar knee arthroplasties were reviewed after eight to 12 years of follow-up evaluation. Eighteen patients (19 knees) had died, four patients (four knees) were lost to follow-up evaluation, and 13 patients (13 knees) had revision. Survivorship analysis revealed 90% survivorship of the prostheses at nine years, 85% at ten years, and 82% at 11 years. Sixty-four knees in 51 patients were studied clinically and roentgenographically at final follow-up study. Of these, 87% had no significant pain. The average knee flexion was 115 degrees. Anatomic knee alignment averaged 3 degrees of valgus for the knees with preoperative varus alignment and 8 degrees of valgus for knees with preoperative valgus alignment. Fifteen percent of these elderly patients (mean age, 80 years) used a cane outdoors, but only 8% because of their knee. Sixty percent had radiolucent lines at the tibial bone-cement interface, and these lines were incomplete in 96% of cases.     

Unicompartmental Oxford Meniscal knee arthroplasty

Unicompartmental knee arthroplasty is an attractive concept, but some reports on its use are unfavorable. A meniscal bearing prosthesis has many advantages in this mode of arthroplasty. The authors present preliminary results of 25 unicompartmental knee replacements done with the Oxford Meniscal knee, with a follow-up period of 12-54 months (mean, 21 months). They discuss the scientific basis of unicompartmental knee arthroplasty, which they conclude may be the most appropriate treatment for selected cases of degenerative arthritis of the knee.     

Unicompartmental and total knee arthroplasty

Pain is the main indication for a total knee arthroplasty, and the choice of prosthesis should depend on the arthritic involvement of the joint. There is no substitute for early motion after the operation to regain knee motion. Unicompartmental replacement is valuable to preserve ligament and bony stock in properly selected cases. Excellent results can be expected in even elderly patients with severe arthritis if the operation is well performed.     

Review of the all-polyethylene tibial component in total knee arthroplasty. A minimum seven-year follow-up period

A retrospective analysis of 144 total knee arthroplasties was performed between 1975 and 1981 with a minimum follow-up period of seven years. A posterior cruciate condylar prosthesis was used in each procedure. Patients were followed clinically and roentgenographically, and a set of statistical variables was established based on elevation in joint line, tibial component angular alignment, overall limb alignment, and position of the tibial component on anteroposterior and lateral roentgenograms. Review of the study group found that the Hospital for Special Surgery knee scores improved from a preoperative score of 55 to a postoperative score of 88, with 94.5% having good or excellent results. The mean postoperative range of motion was 106 degrees with a mean extension of -0.3 degrees. Radiolucencies developed in 41% of the knees with 5% of the knees having progressive radiolucencies. Eight knees were considered failures based on clinical and roentgenographic evaluations. Factors found to significantly affect the formation of radiolucent lines included a shift of the tibial component medially by greater than 4 mm, a varus tilt of the tibial component greater than 2 degrees, and the diagnosis of rheumatoid arthritis. The only variable associated with aseptic loosening was an elevation of the joint line by greater than 8 mm.     

Distal femoral varus osteotomy for lateral osteoarthritis of the knee: a minimum ten-year follow-up

Distal femoral varus osteotomy (DFVO) may be indicated for symptomatic lateral compartment gonarthrosis associated with valgus deformity in younger, active patients. Thirty-three consecutive DFVOs (31 patients) with a minimum follow-up of ten years (mean 15.1, range 10–25) were reviewed. Fifteen DFVOs were converted to total knee arthroplasty (TKA) and one DFVO was awaiting TKA, reaching an overall failure rate of 48.5% at a mean of 15.6 years (range 6–21.5). Of the remaining 17 DFVOs, ten (58.8%) had good or excellent results, two (11.8%) had fair results and five (29.4%) had poor results. Mean modified Knee Society scores improved significantly (p < 0.01) from 36.8 preoperatively to 77.5 at one year post DFVO. DFVO is a viable treatment alternative for lateral compartment gonarthrosis. Conversion to TKA is expected to be required in approximately half of the patients at a mean of 15.6 years.     

Excellent results with cementless total hip arthroplasty and alumina-on-alumina pairing: minimum ten-year follow-up

Ceramic-on-ceramic coupling is thought to be a durable alternative to metal- or alumina-on-polyethylene pairing. No evidence exists suggesting superior clinical and radiological results for hydroxyapatite-coated stems versus uncoated stems. The aim of this study is to report the performance of an alumina-on-alumina bearing cementless total hip arthroplasty and to compare stems with a tapered design with and without hydroxyapatite coating. We prospectively analysed the results of cementless tapered femoral stems (40 hydroxyapatite-coated versus 22 uncoated stems), a metal-backed fibre mesh hydroxyapatite-coated socket and alumina-on-alumina pairing. Of 75 hips studied, 62 were available for follow-up (mean of 10.5 years after surgery). The average Harris hip score was 90. Only one hydroxyapatite-coated stem was revised for aseptic loosening. One instance of non-progressive osteolysis was detected around a screw of a cup. All other components showed radiographic signs of stable ingrowth. Hydroxyapatite coating of the stem had no significant impact on the clinical or radiological results. Total hip arthroplasty with the presented implant and pairing provides a durable standard for all patients requiring hip joint replacement against which all newer generations of cementless implants should be judged.     

单髁膝关节置换治疗膝关节单间室病变

[目的]了解单髁膝关节置换治疗单问室膝关节病变的早期疗效,探讨单髁膝关节置换手术的手术适应证和手术技术难点.[方法]采用轻度矫正不足(slightly undercorrect)原则和内侧有限松解技术对15例各类单间室膝关节病变患者行单髁膝关节置换术,对术前和随访时HSS评分,股胫角,最大关节活动度进行统计分析,并测量胫骨假体后倾角度.[结果]HSS评分,股胫角,最大关节活动度均较术前有显著改善,胫骨平台后倾角度平均4.2°.[结论]单髁膝关节置换治疗膝关节病变的早期疗效可靠,严格把握手术适应证是单髁膝关节置换疗效的保证,内侧有限松解技术能有效改善屈曲挛缩.     

Roentgenographic evaluation of geometric total knee arthroplasty with a six-year average follow-up period

The geometric total knee prosthesis was used in the reconstruction of 70 damaged knee joints in 56 patients from November 1973 through March 1979. The average follow-up period extended to six years and seven months. Eleven patients had died and four could not be located. Eighty-one percent of the remaining knees had little or no pain at the time of the review. Pain in the patellofemoral joints was an insignificant problem in this series. The femorotibial shaft angle ranged from 0 degrees to 10 degrees of valgus in 43 (82.7%) of 52 knees. Six knees showed varus deformity at the time of follow-up examination. Stress fracture of the medial condyle of the tibia was found in two of these six knees. The absence of a radiolucent zone at the tibial cement-bone interface was noted in only ten (19.2%) of the 52 knee roentgenograms. New formation or progression of a radiolucent zone from six to 12 months after the operation was found in 36.5%. Positional abnormality of the marker wires seen in serial roentgenograms existed in 51.9% of the knees. Nine knees (17.3%) disclosed a gap between the metallic articular surface and the tibial component and also showed the collision of the tibial intercondylar eminence against the femur in the standing position. The tibial component of the prosthesis was fractured in one knee.