Progressive Radiolucent Lines Research Articles

Clinical Performance, Patient Reported Outcome, and Radiological Results of a Short, Tapered, Porous, Proximally Coated Cementless Femoral Stem: Results up to Seven Years of Follow-Up

BackgroundThe primary aim of our study was to assess clinical performance, patient reported outcome and radiological results of cementless primary total hip arthroplasty using Tri-Lock Bone Preservation Stem. MethodsBetween March 2010 and June 2012, 163 consecutive patients, were enrolled in the study. Patients were assessed clinically and radiographically prior to surgery as well as at 6, 12, 24 months and then at 5, 6, and 7 years postoperatively. ResultsUsing the Dorr classification, 39 patients (23.9%) were classified as Dorr A, 116 patients (71.2%) as Dorr B, and 8 patients (4.9%) as Dorr C. A total of 139 patients (85.3%) received a high offset, whereas 24 patients (14.7%) received a standard offset stem. Total Harris Hip Score of the patients increased from a mean of 27.29 (±4.6) preoperatively, upto 97.28 (±9.0) after 5 years. Mean preoperative Short Form-12 (SF-12) Physical Health Composite Scale score was 27.31 (±3.8). After 5 year was 55.3 (34-57). The mean preoperative SF-12 Mental Health Composite Scale score was 57.02 (±5.9). After 5 year was 59.3 (28.7-60.8). Only one patient underwent revision surgery for dislocation and revision of the head. ConclusionTri-lock Bone Preservation Stem DePuy proved to be an easy-to-use device. Results obtained up to 7 years of FU show excellent clinical performance, as well as radiographic osseointegration, with no cases of aseptic loosening and no images of progressive radiolucent lines or periprosthetic osteolysis.

Minimum 20 Year Follow-Up of Semi-Constrained Total Ankle Arthroplasty

Category: Ankle Arthritis Introduction/Purpose: With the introduction of newer generations of total ankle arthroplasty (TAA) constructs, the incidence of TAA in the United States has been increasing. While TAA has emerged as an alternative to ankle arthrodesis for the management of end-stage ankle arthritis, long-term data evaluating clinical outcomes and the survivorship of ankle prostheses is lacking. The purpose of this study was to report the clinical outcomes and radiographic survivorship of a second-generation, semi-constrained titanium and cobalt-chromium total ankle prosthesis at minimum twenty-year follow-up in order to provide a benchmark comparison for future generations of TAA design. Methods: 132 total ankle replacements in 126 patients were performed by a single surgeon between July 1984 and October 1994. Follow-up evaluation consisted of determining revision status, completion of the validated ankle osteoarthritis scale, a short questionnaire, and a review of the available radiographs. All radiographs were evaluated for evidence of progressive radiolucent lines, osteolysis and component subsidence. Results: At minimum twenty-year follow-up, 37 patients were alive, 89 were deceased, and 5 were lost to follow-up. For living patients, average clinical follow up was 25.3 years. Average radiographic follow-up was 21.4 years. Over the minimum 20 year follow-up, 29 ankles were revised (23%). For living patients, 13 ankles were revised (35%). Conclusion: Twenty-three percent of all patients and 35% of living patients required a revision over the minimum 20 year follow up interval. 65% of living patients have retained their prosthesis and 75% of the entire cohort are still functioning with their original ankle replacement or died with the original ankle replacement in place. This study should provide a benchmark for newer designs when they obtain this length of follow-up.

Five-year clinical and radiological outcomes in 257 consecutive cementless Oxford medial unicompartmental knee arthroplasties

Our aim was to examine the clinical and radiographic outcomes in 257 consecutive Oxford unicompartmental knee arthroplasties (OUKAs) (238 patients), five years post-operatively. A retrospective evaluation was undertaken of patients treated between April 2008 and October 2010 in a regional centre by two non-designing surgeons with no previous experience of UKAs. The Oxford Knee Scores (OKSs) were recorded and fluoroscopically aligned radiographs were assessed post-operatively at one and five years. The median age of the 238 patients was 65.0 years (interquartile range (IQR) 59.0 to 73.0), the median body mas index was 30.0 (IQR 27.5 to 33.0) and 51.7% were male. There were no intra-operative complications. There was a significant improvement in the median OKS at six weeks (34, IQR 31.0 to 37.0), one year (38, IQR 29.0 to 43.0) and five years (37, IQR 27.0 to 42.0) when compared with the pre-operative scores (16, IQR 13.0 to 19.0) (all p = < 0.01). No patient had progressive radiolucent lines or loosening. A total of 16 patients had died by five years. The cumulative survival at five years was 98.8% and the mean survival time was 5.8 years (95% confidence interval 5.6 to 5.9). A total of seven OUKAs (2.7%) were revised; three within five years and four thereafter, between 5.1 and 5.7 years post-operatively. Five (1.9%) had re-operations within five years. The proportion of patients requiring revision at five years is lower than that generally reported for UKA. These findings add support for the use of the cementless OUKA outside the design centre. Longer follow-up is required. Cite this article: Bone Joint J 2017;99-B:623-31.

Results of the cemented Exeter femoral component in patients under the age of 40 : an update at ten to 20 years' follow-up.

We carried out a further study of the long-term results of the cemented Exeter femoral component in patients under the age of 40 with a mean follow-up of 13.6 years (10 to 20). We reviewed our original cohort of 104 cemented Exeter stems in 78 consecutive patients with a mean age of 31 years (16 to 39). Only one patient was lost to radiological follow-up. A total of six patients (eight hips) had died for reasons unrelated to their surgery. There had been one further periprosthetic fracture from a fall and one fractured femoral stem. No revisions for aseptic loosening were undertaken during the whole study period. Overall, 11 hips had progressive radiolucent lines in one or more zones. The Kaplan Meier survival percentages at ten and 17 years were 97.1% (95% confidence interval (CI) 91.3 to 99.1) and 92.1% (95% CI 74.1 to 97.8) with revision for any reason as the endpoint, and 100% at both ten and 17 years with aseptic loosening (95% CI 83.8 to 100) as the endpoint. No additional hips were classified as radiologically loose. The Exeter femoral component continues to function satisfactorily in young patients for up to 17 years after surgery. Cite this article: Bone Joint J 2017;99-B:192-8.

Results of Total Elbow Arthroplasty with Cementless Implantation of an Alumina Ceramic Elbow Prosthesis for Patients with Rheumatoid Arthritis.

We investigated the long-term clinical results of total elbow arthroplasty (TEA) by cementless fixation of alumina ceramic unlinked elbow prostheses (J-alumina ceramic elbows: JACE) for the reconstruction of elbow joints with rheumatoid arthritis (RA). Seventeen elbows in 17 patients (aged 44-72 years, average 54.8) replaced by JACE TEA without bone cement were investigated. The average follow-up period was 10.7 (range, 1.0-19.3) years. Clinical conditions of each elbow before and after surgery were assessed according to the Mayo Elbow Performance Index (MEPI). Radiographic loosening was defined as a progressive radiolucent line of more than 1 mm that was completely circumferential around the intramedullary stem. The average MEPI significantly improved from 46.8 points preoperatively to 66.8 points at final follow-up (p=0.0226). However, aseptic loosening was noted in 10 of 17 elbows (58.8%) and revision surgery was required in 7 (41.2%). Most loosening was observed on the humeral side. With radiographic loosening and revision surgery defined as the end points, the likelihoods of prosthesis survival were 41.2% and 51.8%, respectively, up to 15 years by Kaplan-Meier analysis. The clinical results of JACE implantation without bone cement were disappointing, with high revision and loosening rates of the humeral component.

Long-term results of total knee arthroplasty in haemophilic patients: an 18-year follow-up.

Total knee arthroplasty (TKA) for patients with end-stage haemophilic arthropathy is considered to be a successful procedure with satisfying mid- to long-term results. It was the purpose of this study to provide clinical and radiological long-term results of TKAs implanted in a consecutive cohort of haemophilic patients. Primary TKA was performed in 43 consecutive knees in 30 haemophilic patients. After a mean of 18 (SD±4) years, 15 patients (21 knees) with a mean age of 58 (SD±8) years were available for follow-up. The outcome was assessed using the Knee Society score, WOMAC, SF-36, Kaplan-Meier survivorship analysis as well as radiographic evaluation of radiolucency. In 13 (30%) of the 43 consecutive knees, revision surgery was necessary due to infection or aseptic loosening, among which eight (19%) due to aseptic loosening and five (12%) due to haematogenous infection. The calculated 20-year survival rates with revision for any reason or infection as the end points were 59 and 82%, respectively. All patients with the primary TKA in situ observed progressive radiolucent lines around the implants at the final follow-up. The Knee Society clinical and functional score significantly improved from pre- (36 points; SD±16 and 62 points; SD±19) to post-operatively (73 points; SD±15 and 78 points; SD±18; p<0.001). Eighty-six per cent rated their result as either good or excellent. Whereas flexion did not improve, flexion contracture could be reduced significantly from 18° (SD±12) to 6° (SD±5; p<0.001) post-operatively. Total knee arthroplasty in haemophilic patients is associated with high revision, loosening and infection rates after 18years. However, if revision can be avoided, joint replacement in haemophilic patients helps to relieve pain, achieve higher subjective satisfaction and to restore knee function. Level of evidence IV.

Progressive radiolucent lines following the implantation of the cemented Rimfit acetabular component in total hip arthroplasty using the rimcutter technique: cause for concern?

The highly cross-linked polyethylene Exeter RimFit flanged cemented acetabular component was introduced in the United Kingdom in 2010. This study aimed to examine the rates of emergence of radiolucent lines observed when the Rimfit acetabular component was implanted at total hip arthroplasty (THA) using two different techniques: firstly, the 'rimcutter' technique in which the flange sits on a pre-prepared acetabular rim; and secondly, the 'trimmed flange' technique in which the flange is trimmed and the acetabular component is seated inside the rim of the acetabulum. The radiographs of 150 THAs (75 'rimcutter', 75 'trimmed flange') involving this component were evaluated to assess for radiolucencies at the cement/bone interface by three observers. Rimfit acetabular components implanted using the rimcutter technique had significantly higher rates of radiolucency than those introduced using the 'trimmed flange' technique one year post-operatively (one zone: 63/75 (84%) vs 17/75 (23%); two zones 42/75 (56%) vs 0/75 (0%); all three zones 17/75 (23%) vs 0/75 (0%):(all p < 0.001). On the basis of these findings, we have stopped using the 'rimcutter' technique when implanting the Rimfit acetabular component and have reverted to the 'trimmed flange' technique. Surgeons should be vigilant of the performance of the Rimfit acetabular component when used alongside the rim cutter device due to an observed higher rate of progressive radiolucencies with this combination of component / technique.

Glenoid cement mantle characterization using micro–computed tomography of three cement application techniques

Numerous studies have documented the concern for progressive radiolucent lines, signifying debonding and subsequent aseptic loosening of the glenoid component. In this study, we compared 3 cementation methods to secure a central peg in 15 cadaveric glenoids. Cement application techniques consisted of (1) compression of multiple applications of cement using manual pressure over gauze with an Adson clamp, (2) compression of multiple applications of cement using a pressurizer device, and (3) no compression of a single application of cement. Each glenoid was then imaged with high-resolution micro-computed tomography and further processed by creating 3-dimensional computerized models of implant, bone, and cement geometry. Cement morphology characteristics were then analyzed in each of the models. There were no significant differences detected between the 2 types of compression techniques; however, there was a significant difference between compression methods and use of no compression at all. All morphologic characteristics of a larger cement mantle were significantly correlated with greater cortical contact. We demonstrate that compression techniques create a larger cement mantle. Increased size of the cement mantle is associated with increased contact with cortical bone at the glenoid vault. This method for characterizing the cement mantle by micro-computed tomography scanning techniques and 3-dimensional analysis may also be useful in future finite element analysis studies.

Hydroxyapatite-coated collars reduce radiolucent line progression in cemented distal femoral bone tumor implants.

Aseptic loosening of massive bone tumor implants is a major cause of prosthesis failure. Evidence suggests that an osteointegrated hydroxyapatite (HA)-coated collar would reduce the incidence of aseptic loosening around the cemented intramedullary stem in distal femoral bone tumor prostheses. Because these implants often are used in young patients with a tumor, such treatment might extend the longevity of tumor implants. Questions/purposes We asked whether (1) HA-coated collars were more likely to osteointegrate; (2) HA collars were associated with fewer progressive radiolucent lines around the stem-cement interface; and (3) HA-coated collars were associated with less bone loss at the bone-shoulder implant junction? Twenty-two patients were pair-matched to one of two groups--either (1) implants with a HA-coated ingrowth collar (HA Collar Group); or (2) implants without an ingrowth collar (Noncollar Group). Age, sex, and length of followup were similar in both groups. HA-coated collars were developed and used at our institution from 1992 to address the high failure rate attributable to aseptic loosening in patients with massive bone tumor implants. Before this, smooth titanium shafts were used routinely adjacent to bone at the transection site. The minimum followup was 2 years (mean, 7 years; range, 2-12 years). Radiographs obtained throughout the followup period were analyzed and osteointegration at the shaft of the implant quantified. Radiolucent line progression around the cemented stem was semi-quantitatively assessed and cortical bone loss at the bone-shoulder implant junction was measured during the followup period. Comparison of the most recent radiographs showed nine of 11 patients had osteointegrated HA collars, whereas only one patient in the Noncollar Group had osteointegration (p > 0.001). The radiolucent line score quantified around the cemented stem was lower in the HA Collar Group when compared with the Noncollar Group (p = 0.001). Results showed an increase in cortical bone loss at the bone-shoulder implant junction in the Noncollar Group when compared with the HA Collar Group (p < 0.001). Osteointegration at the implant collar resulted in fewer radiolucent lines adjacent to the intramedullary cemented stem and decreased cortical bone loss immediately adjacent to the transection site. These results suggest that the HA collar may help reduce the risk of aseptic loosening in patients with this type of implant, but longer followup and a larger prospective comparison series are necessary to prove this more definitively.

Long-term survival of the glenoid components in total shoulder replacement for arthritis.

Aseptic glenoid component loosening remains a common problem in total shoulder arthroplasty (TSA). This study presents long-term prospective follow-up after implantation of a glenoid component using the "cancellous compaction technique" and its effect on clinical outcome and presence and progression of radiolucent lines (RLLs). Thirty-nine TSAs were performed for primary osteoarthritis by one surgeon using the same technique. For the glenoid side, a keeled, polyethylene, convex-backed component was implanted using the "cancellous compaction technique" consisting of minimal reaming, compaction bone grafting of the glenoid and minimal addition of cement. Postoperative clinical outcome was analysed using Constant scores and patient's subjective evaluation. Independent observers evaluated postoperative X-rays for radiolucent lines (RLL) around the base plate and keel. At an average follow-up of 8.5years (range 4.7-12.5), the Constant score improved from 33.5 to 73.0 points (P < 0.0001). Active anterior elevation improved from an average 95 ° to 140° (P < 0.0001), and active external rotation improved from 20° to 45° (P < 0.0001). Pain score improved from 3.1 to 13.6 (P < 0.0001). Radiologically, the RLL score increased from 1.09 (range, 0-3) postoperative to 5.7 (range, 0-18) (P < 0.0001) at final follow-up. The occurrence of definite radiological glenoid loosening was 15.5%. Constant scores deteriorated with the progression of RLLs (P = 0.006). The rate of revision surgery for glenoid loosening was 2.5%. This study showed highly satisfactory clinical outcomes and low rates of revision for glenoid loosening using a bone-saving compaction technique for implantation of an all-polyethylene glenoid component.

Revision total knee arthroplasty using metaphyseal sleeves at short-term follow-up.

The treatment of bone loss in revision total knee arthroplasty (TKA) has involved using revision implants in association with cement, augments, particulate, and structural allograft. Newer metaphyseal augments were introduced to allow for metaphyseal fixation of the prosthesis while managing significant bone loss. The purpose of the current study was to evaluate the outcome of revision TKA using metaphyseal sleeves. The authors prospectively followed 96 knees that underwent revision TKA with metaphyseal sleeves. Eighty-three knees met the minimum 2-year criteria for follow-up. Thirty-six sleeves were used in femoral revisions and 83 sleeves were used in tibial revisions. The defects were classified according to the Anderson Orthopaedic Research Institute classification. Femoral defects were classified as type I in 4 knees, type IIb in 25 knees, and type III in 7 knees. Tibial defects were classified as type I in 9 knees, type IIa in 1 knee, type IIb in 68 knees, and type III in 5 knees. The patients were followed for an average of 2.4 years (range, 2.0-3.7 years). Mean Knee Society function score improved from 47.9 to 61.1 points. Mean Short Form 36 physical score improved from 43.3 to 56.3 points. Mean Western Ontario and McMaster Universities Arthritis Index improved from 55.3 to 25.9 points. None of the implants demonstrated progressive radiolucent lines around the metaphyseal sleeves. At final follow-up, only 2 (2.7%) tibial components required revision for aseptic loosening. At short-term follow-up, revision TKA with metaphyseal sleeves provided reliable fixation. This is especially encouraging given the severe nature of bone loss in the majority of patients in whom a metaphyseal sleeve was used. Long-term follow-up is needed to demonstrate the true effectiveness of these devices.

NexGen® LPS mobile bearing total knee arthroplasty: 10-year results.

Mobile bearing (MB) knee prostheses were designed to improve the performances of the total knee arthroplasties (TKA). The clinical superiority of MB prosthesis compared to its fixed bearing counterpart has remained elusive. This study prospectively evaluates the cumulative survivorship, clinical, radiographic results, and complications of a large series of MB TKAs in relation to patient age, sex, severity of arthritis, and patellar resurfacing. This study evaluates the 5- to 10-year cumulative survival rate of the NexGen(®) LPS MB. Between 2000 and 2005, we performed a consecutive series of 332 MB, posterior-stabilized TKA in 249 patients (mean age 71.2 years, SD 6.9). The implants were clinically evaluated with the Hospital Special Surgery Knee Score (HSS-KS) and radiographically with the Knee Society Roentgenographic Evaluation System (KS-RES). The mean follow-up was 76.3 months (minimum 5 years). The HSS-KS improved from 55 pre-operatively to 86 at the end of follow-up. According to the KS-RES, the implants were anatomically aligned and progressive radiolucent lines appeared in four knees (1.2 %). The patella was selectively resurfaced in 162 of 332 knees. Patients with the patella resurfaced had better clinical results compared to those not resurfaced, but there was no difference in terms of survival. The cumulative survival rate was 98.4 % at 10 years (Kaplan-Meier's analysis). This MB implant provided reliable and durable clinical results with a survivorship of over 98 % at 10 years, in unselected patients regardless of age, sex, severity of disease, and patellar treatment.

A 5-22-year follow-up study of stemmed alumina ceramic total elbow arthroplasties with cement fixation for patients with rheumatoid arthritis

BackgroundWe determined mid to long-term results of total elbow arthroplasty (TEA) by use of unlinked elbow prostheses with solid alumina ceramic trochleae, and ceramic ulnar stems (stemmed Kyocera type I; SKC-I) for patients with rheumatoid arthritis. Patients and methodsFifty-four elbows of 39 patients were available for detailed clinical and radiographic review after a follow-up period of at least 5 years. The mean follow-up period was 12.6 years (range 5-22 years). Clinical condition before and after surgery was assessed by use of a modified version of the Mayo Elbow Performance Score (MEPS; 0-100 points) and a Japan Orthopaedic Association Elbow score (JOA score; 0-100 points). The radiographs were reviewed and loosening was defined as a progressive radiolucent line >1 mm wide that was completely circumferential around the prosthesis. Clinical records of post-operative events affecting the elbows were used for survival analysis of the prostheses using the Kaplan-Meier method. ResultsThe average modified MEPS and JOA scores improved significantly from 39.7 ± 14.3 to 44.7 ± 9.4, respectively, pre-operatively, to 89.7 ± 15.4 and 83.1 ± 12.8, respectively, post-operatively (P< 0.0001). The functional assessment score also improved from 4.9 ± 2.8 to 8.5 ± 3.3 points (P < 0.0001). With loosening or implant revision defined as end points, the likelihood of survival of the prosthesis for up to 20 years was 92.6 % (95 % confidence interval (CI), 85.6-100.0) or 86.3 % (95 % CI 75.0-97.6), respectively. ConclusionSatisfactory clinical results were obtained after TEA using SKC-I prostheses, which provided excellent pain relief and functional range of motion. The results of our study reveal the high reliability over a long period of the cemented SKC-I prosthesis with an alumina ceramic component.

Endo-Modell Rotating-hinge Total Knee for Revision Total Knee Arthroplasty

The goal of this study was to analyze the clinical and radiographic results and the survival rate of a series of rotating-hinge implants used for revision total knee arthroplasties in mild and severe instability. Between December 1991 and June 2004, fifty-three revision total knee arthroplasties were performed using the Endo-Modell (Waldemar LINK GmbH and Co, Hamburg, Germany) rotating-hinge prosthesis; 7 (13.2%) patients underwent partial revision of a previous Endo-Modell. All patients were evaluated preoperatively, 3 and 6 months postoperatively, and annually thereafter using the Hospital for Special Surgery (HSS) knee score and the Knee Society Roentgenographic Evaluation System (KS-RES). Mean follow-up was 155.2±40.1 months (range, 78-240 months), with 32 patients examined at the final follow-up. All HSS knee scores increased from preoperatively to last follow-up. No statistically significance differences were found in the HSS knee scores between septic and aseptic revisions and between total or partial revisions. Progressive radiolucent lines were detected in 8 (25%) patients. Implant failure occurred in 11 (20.7%) patients; the cumulative survival of the implants was 80.4% at 150 months for the final 32 patients. The authors recommend use of this implant for revision total knee arthroplasty, especially in patients with severe instability and bone loss.

Total Hip Arthroplasty with Porous Metal Cups following Acetabular Fracture

Total hip arthroplasty (THA) after acetabular fracture presents unique challenges, including acetabular fixation. Twelve patients with a history of acetabular fracture underwent THA with porous metal cups. The average age was 57 years (range 24-88). THA was performed at an average 20 months from initial fracture. Average follow-up was 39 months (range 24-49). Average WOMAC scores improved from 32 to 79; UCLA scores improved from 1.75 to 5.25. There was one case of acetabular loosening in a renal transplant patient with rheumatoid arthritis. No other patients showed progressive radiolucent lines. At average three-year follow-up, porous metal components afforded improved clinical and radiographic outcomes in the majority of patients. Longer follow-up will determine whether porous metal is a durable option in the management of prior acetabular fracture.

The Oxford Unicompartmental Knee Fails at a High Rate in a High-volume Knee Practice

The Oxford knee is a unicompartmental implant featuring a mobile-bearing polyethylene component with excellent long-term survivorship results reported by the implant developers and early adopters. By contrast, other studies have reported higher revision rates in large academic practices and in national registries. Registry data have shown increased failure with this implant especially by lower-volume surgeons and institutions. In the setting of a high-volume knee arthroplasty practice, we sought to determine (1) the failure rate of the Oxford unicompartmental knee implant using a failure definition for aseptic loosening that combined clinical features, plain radiographs, and scintigraphy, and (2) whether increased experience with this implant would decrease failure rate, if there is a learning curve effect. Eighty-three Oxford knee prostheses were implanted between September 2005 and July 2008 by the principal investigator. Radiographic and clinical data were available for review for all cases. A failed knee was defined as having recurrent pain after an earlier period of recovery from surgery, progressive radiolucent lines compared with initial postoperative radiographs, and a bone scan showing an isolated area of uptake limited to the area of the replaced compartment. Eleven knees in this series failed (13%); Kaplan-Meier survivorship was 86.5% (95% CI, 78.0%-95.0%) at 5 years. Failure occurrences were distributed evenly over the course of the study period. No learning curve effect was identified. Based on these findings, including a high failure rate of the Oxford knee implant and the absence of any discernible learning curve effect, the principal investigator no longer uses this implant.

Mid term results of LCS knee: The Indian experience

Background:The low contact stress rotating platform (LCS RP) knee (DePuy Orthopedics, Inc, Warsaw, Indiana), in use for last four decades in Western population, is reported to have a survival of more than 95% at 15 to 20 years. The reported Indian experience of this knee is limited to 5 years. Our aim was to report the clinical and radiological results of the LCS RP TKA design in the Indian population with a minimum followup of 10 years.Materials and Methods:Fifty-five LCS knees (45 patients) operated between February 1997 and October 2001 were evaluated retrospectively. LCS design was generally selected if the patient was young (≤65 years of age), active and had no severe deformity. There were 40 female (88.9%) and 5 male (11.1%) patients; 47 knees had osteoarthritis (85.5%) and 8 knees had rheumatoid arthritis (14.5%). Knee Society Scores (KSS) and outcome questionnaire were filled at followup and radiographs were analyzed using Knee Society radiographic evaluation and scoring system.Results:Of 45 patients (55 knees) enrolled, 37 patients (44 knees; 80%) were available for followup at 10 years. Average age was 59.6 years (range 40 to 77). Minimum followup was 10 years (average 12.3 years; range 10 to 15.3 years.). Three knees (6.8%) had been revised, one each for aseptic loosening, bearing dislocation and infection. Mean preoperative KSS of 33 improved to 91 postoperatively. Mean preoperative functional score of 45 improved to 76 postoperatively. Mean preoperative flexion of 113° (90°-140°) reduced to 102° (80°-135°) postoperatively. Erratic femoral rollback and tighter flexion gap to prevent spin out are the probable factors for decreased postoperative range of motion. Five (12%) patients could sit cross-legged and sit on the floor. Anterior knee pain was present in 4.6% (2/44 knees). The survival was 93.2% at 12.3 years. One patient (1.8%) had spin-out of the rotating bearing. No knee had osteolysis or progressive radiolucent lines on X-rays.Conclusion:LCS implant has given good survival (93.2% at 12.3 years) with low rates of spin-out and anterior knee pain and no incidence of osteolysis. Limited flexion post surgery (104°) with only 12% managing to sit cross legged on the floor is a drawback.

Excellent Fixation Achieved With Cementless Posteriorly Stabilized Total Knee Arthroplasty

Cementless posteriorly stabilized (PS) total knee arthroplasty has not been widely accepted primarily because of prior unpredictable results and concern about micromotion at the tibial fixation interface caused by the cam/post interaction. A prospective consecutive series of 114 cementless, tricompartmental periapatite-coated single-radius PS implants in 110 patients with a mean age 62 years was performed to determine if initial stability and biologic fixation could be achieved. At a mean follow-up of 36 months, all implants demonstrated radiographic evidence of stable biologic fixation with no evidence of loosening, osteolysis, stress shielding, or progressive radiolucent lines. Based on these early results, cementless, periapatite-coated single-radius PS total knee arthroplasty offers marked promise.

Ceramic Femoral Components in Total Knee Arthroplasty - Two Year Follow-Up Results of an International Prospective Multi-Centre Study

Background: Total knee arthroplasty can be considered as a reliable surgical procedure with a good long-term clinical result. However, implant failure due to particle induced aseptic loosening as well as the aspect of hypersensitivity to metal ions still remains an emerging issue.Methods: The purpose of this prospective international multi-centre study was to evaluate the clinical and radiological outcomes and the reliability of the unconstrained Multigen Plus Total Knee System with a new BIOLOX® delta ceramic femoral component. Cemented total knee arthroplasty was performed on 108 patients (110 knees) at seven hospitals in three countries. Clinical and radiological evaluations were performed preoperatively, and after 3, 12 and 24 months postoperatively using the HSS-, WOMAC-, SF-36-score and standardised X-rays.Results: The mean preoperative HSS-Score amounted to 55.5 ± 11.5 points and improved significantly in all postoperative evaluations (85.7 ± 11.7 points at 24 months). Furthermore, improvements in WOMAC- and SF-36-score were evaluated as significant at all points of evaluation. Radiolucent lines around the femoral ceramic component at 24 months were found in four cases. Progression of radiolucent lines was not seen and no implant loosening was observed. During the 24 month follow-up eight patients underwent subsequent surgery due to reasons unrelated to the implant material.Conclusions: The observed clinical and radiological results are encouraging for a long-term survival of the ceramic femoral component. Therefore, ceramic implants could be a promising solution not only for patients with allergies against metallic implant materials, but also for the osteoarthritic knee joint. Long-term follow-up is necessary to draw conclusions regarding the superiority of the ceramic knee implants concerning in vivo wear and long-term survivorship.

Heat Generated With Pegged or Keeled Glenoid Components Fixed With Defined Amounts of Cement

Glenoid component loosening is a common complication of total shoulder arthroplasty and has been associated with the progression of radiolucent lines at the glenoid bone-cement interface. Generation of heat during the exothermic reaction of cement curing may cause osteonecrosis of bone, potentially leading to the development of radiolucent lines. The purpose of this study was to measure the heat generated with various defined amounts of cement used for glenoid component fixation.Ten fresh-frozen cadaver scapulas were randomized to receive a keeled or pegged component with 1, 2, 3, 5, or 7 g of cement for fixation. An infrared camera was used to record the surface temperature generated during the cement curing process to an accuracy of ±2.0°C. Computed tomography was used to evaluate the cement mantle. The maximum temperatures generated did not exceed the critical value for osteonecrosis (56°C) in any of the specimens. The 4 specimens without a complete mantle were those fixed with a smaller quantity of cement (1, 2, or 3 g), and the largest cement mantle thicknesses were observed with the use of 7 g of cement.Up to 7 g of cement can be used without significant concern for thermal necrosis. Incomplete cement mantles were observed when ≤3 g of cement was used for fixation. Our results suggest that surgeons should use >3 g of cement to avoid incomplete cement mantles and that up to 7 g of cement can safely be used for glenoid fixation.