Dissatisfied patients after total knee arthroplasty: A registry study involving 114 patients with 8–13 years of follow-up

Background and purpose

In 2003, an enquiry by the Swedish Knee Arthroplasty Register (SKAR) 2–7 years after total knee arthroplasty (TKA) revealed patients who were dissatisfied with the outcome of their surgery but who had not been revised. 6 years later, we examined the dissatisfied patients in one Swedish county and a matched group of very satisfied patients.

Patients and methods

118 TKAs in 114 patients, all of whom had had their surgery between 1996 and 2001, were examined in 2009–2010. 55 patients (with 58 TKAs) had stated in 2003 that they were dissatisfied with their knees and 59 (with 60 TKAs) had stated that they were very satisfied with their knees. The patients were examined clinically and radiographically, and performed functional tests consisting of the 6-minute walk and chair-stand test. All the patients filled out a visual analog scale (VAS, 0–100 mm) regarding knee pain and also the Hospital and Anxiety and Depression scale (HAD).

Results

Mean VAS score for knee pain differed by 30 mm in favor of the very satisfied group (p < 0.001). 23 of the 55 patients in the dissatisfied group and 6 of 59 patients in the very satisfied group suffered from anxiety and/or depression (p = 0.001). Mean range of motion was 11 degrees better in the very satisfied group (p < 0.001). The groups were similar with regard to clinical examination, physical performance testing, and radiography.

Interpretation

The patients who reported poor response after TKA continued to be unhappy after 8–13 years, as demonstrated by VAS pain and HAD, despite the absence of a discernible objective reason for revision.The results of TKA are regarded as being favorable (Robertsson et al. 2000, Kane et al. 2005, Nilsdotter et al. 2009, Carr et al. 2012) with few surgical complications and a revision rate of less than 5% after 10 years (Vessely et al. 2006, Robertsson et al. 2010). Poor outcome after primary TKA, apart from the revision, is between 6% and 14% (Anderson et al. 1996, Hawker et al. 1998, Heck et al. 1998, Robertsson et al. 2000, Robertsson and Dunbar 2001, Brander et al. 2003, Noble et al. 2006, Fisher et al. 2007, Wylde et al. 2008, Kim et al. 2009, Bourne et al. 2010, Scott et al. 2010). The reason for poor outcome after TKA may be related to problems with the knee surgery itself, although it has been suggested that extra-articular causes such as hip disease, spine disorder, vascular disease, or reflex sympathetic dystrophy may contribute. Some studies have suggested that factors not primarily related to structural tissue changes, but of psychological nature instead, may be involved (Wylde et al. 2007, Rolfson et al. 2009).The Swedish Knee Arthroplasty Register (SKAR) registers primary arthroplasties performed in Sweden as well as revisions, and has been estimated to capture 97% of the surgeries performed (SKAR 2012). The SKAR sends questionnaires regarding satisfaction to patients who were operated on during certain time periods (Robertsson et al. 2000, and Dunbar 2001). We used the SKAR to identify patients who had not undergone revision surgery and who were dissatisfied with their outcome 2–7 years after TKA surgery. As a reference we chose an age-, sex-, date-of-surgery-, and hospital-matched control group of highly satisfied patients who were operated during the same period. Our aim was to assess the differences between these 2 patient groups.     

Association of body mass index and clinical outcome 2 years after unicompartmental knee arthroplasty

Introduction  Unicompartmental knee arthroplasty (UKA) has gained in popularity during the last years. However, the body mass index (BMI) of patients undergoing UKA is controversially discussed in the literature. There is, moreover, a paucity of information available concerning the association of BMI with early clinical outcomes after UKA. Materials and methods  We retrospectively reviewed the clinical data of 83 consecutive UKA, 2 years after surgery, and investigated the potential association of BMI and the outcome variables Knee Society Score (KSS), University of California at Los Angeles (UCLA) activity levels, anterior knee pain (AKP), range of motion, and implant failure. Results  The KSS and UCLA significantly increased from 132 and 4.7 preoperatively to 187.5 and 7.1, respectively, after surgery. Knee flexion significantly improved from 123.7 to 128.4° and the prevalence of extension deficiencies significantly decreased from 28.9 to 15.7%. Three knees (3.6%) failed and were converted to total knee arthroplasty. Failures were not associated with increased BMI (P = 0.387). The BMI had no significant association with KSS values, UCLA levels, and implant failure. We found a weak negative correlation between BMI and postoperative knee flexion (r = −0.285, P = 0.009) and a moderate positive correlation between BMI and the intensity of AKP (r = 0.525, P < 0.001). Conclusion  The results of the present study suggest that the BMI of patients undergoing UKA has no major impact on the early clinical outcome 2 years after surgery. There was, however, a definite correlation between the BMI and AKP. Longer follow-up is necessary to determine if overweight and obesity may increase revision rates after UKA.     

Failed unicompartmental knee replacement to total knee replacement conversion: Can you achieve a primary outcome?

This review provides an overview of aetiology, diagnosis and management of failed UKRs and highlights key aspects of the decision making process and operative technique to ensure satisfactory outcome after UKR revision surgery.With correct diagnosis and management, in the majority of revision UKR cases outcome similar to primary TKR can be achieved. Unexplained pain, aseptic loosening, infection, progression of arthritis and bearing dislocation are the commonest reasons needing further intervention after UKR. Key messages are about how to reduce the revision risk, methods to critically analyze a painful UKR and when and how to revise a UKR.     

Isolated acetabular revision after total hip arthroplasty: results at 5–9 years of follow-up

The purpose of the study was to determine whether isolated revision of the acetabular component can be successfully performed without disturbing the femoral stem and to determine the fate of the unrevised femoral stem following revision. Fifty-seven hips in 55 patients underwent isolated acetabular revision without removal of the femoral component. Thirty-three hips with minimal acetabular deficiency required no bone grafting; the remaining 24 hips were treated by morselized or structural allograft in addition to a new acetabular component. Twenty-two of these 24 hips demonstrated incorporation of the bone graft. A mean follow-up of 5.8 (5–9) years, all femoral and acetabular components were judged to be stable and well fixed.

---

Résumé Le but de létude est de déterminer si la révision isolé du composant acétabulaire peut être exécutée avec succès sans déranger la tige fémorale et, deuxièmement, de déterminer lavenir de la tige fémorale laissée en place, après cette révision. Cinquante-sept hanches chez cinquante-cinq malades ont subi une révision acétabulaire isolée sans ablation du composant fémoral. Trente-trois hanches avec une déficience acétabulaire minime nont exigé aucune greffe osseuse; les 24 hanches restantes ont été traitées par une allogreffe morcelée ou structurelle associée à un nouveau composant acétabulaire. Vingt-deux de ces 24 hanches ont montré une incorporation de la greffe dos. A un suivi moyen de 5,8 ans (5 à 9 ans) tout les composants fémoraux et acétabulaires ont été jugés stables et bien fixés.

     

Patellar height before and after unicompartmental knee arthroplasty: association with early clinical outcome?

Introduction  There is paucity of information available concerning the role of patellar height in unicompartmental knee arthroplasty (UKA). The present study was conducted to determine the patellar height before and after UKA and to assess possible effects on the early clinical outcome. Materials and methods  We measured the patellar height before and after UKA in 83 consecutive knees using the Blackburne–Peel (BP) index and Insall–Salvati (IS) ratio and investigated the impact of the patellar height on the clinical outcome 2 years after surgery. Results  BP values significantly decreased from 0.81 before surgery to 0.76 postoperatively (P < 0.001). IS ratios did not significantly decrease from 1.02 to 1.01 (P = 0.108). Lower preoperative BP values were negatively correlated with the postoperative knee extension (r = −0.357, P = 0.026), while higher preoperative BP values were negatively associated with the postoperative Knee Society Score (r = −0.302, P = 0.046). Lower preoperative IS values were negatively correlated with postoperative Knee Scores (r = −0.394, P = 0.019). Conclusion  After UKA, the patellar height decreased significantly according to the BP index, but not significantly according to the IS ratio. We found only weak and inconsistent correlations between the patellar height and clinical outcome parameters. Hence, based on the present results, the patellar height seems not to be a strict separate patient-selection criterion for UKA.     

A 5 to 8 year follow-up study of the Rotaglide mobile bearing total knee arthroplasty

We report the medium-term outcomes of the Rotaglide mobile bearing total knee arthroplasty (RTK). Between 1994 and 1999, 357 RTK prostheses were implanted at our institution. Of 150 knees attending for follow-up, none had needed revision. Mean American Knee Society Score (AKSS), Oxford knee score and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score at 8 years were 153.6, 23.1 and 16.5, respectively. Radiological analysis revealed no prosthesis with signs of impending failure requiring revision. Survivorship was 100% in those attending. However, we are aware of two failures requiring revision, both of which were due to infection. We have no reported failures requiring revision due to aseptic loosening. This may be a result of the implant design. Limitations of the study include loss to follow-up and radiological analysis. The RTK gives good to excellent medium-term results and we support its continued use.

---

Résumé  Nous rapportons les résultats à moyen terme de la prothèse à plateau mobile de type Rotaglide. Entre 1994 et 1999, 357 prothèses ont été implantées dans notre établissement. Sur 150 genoux pris en compte dans le suivi aucun n’a nécessité de révision. Les scores AKSS, Oxford et Womac à 8 ans ont été respectivement de153.6, 23.1 et de 16.5. L’analyse radiologique n’a pas montré de signes de faillite nécessitant une révision. La courbe de survie est de 100% sur cette période. Nous surveillons deux échecs qui ont nécessité une révision dont tous les deux sont secondaires à une infection. Nous n’avons pas non plus rapporté d’échecs nécessitant une révision pour descellement aseptique. Ces bons résultats sont secondaires au design de l’implant. Les limites de cette étude sont les perdus de vue de l’analyse radiologique. Nous pouvons conclure que la prothèse totale du genou de type Rotaglide RTK permet de bons et d’excellents résultats à moyen terme et nous sommes encouragés à poursuivre son utilisation.

     

Volumetric measurement of periprosthetic bone remodeling: prospective 5 years follow-up after cemented total hip arthroplasty

Introduction Periprosthetic bone remodeling after total hip arthroplasty (THA) is a well recognized phenomenon. Many authors have published osteodensitometric data with DEXA analysis. This study based on computerized tomography (CT). Materials and methods The objective of the current project is to collect prospective volumetric bone density data with a clinical CT study in six patients after cemented THA (titanium alloy stem). The follow-up time is 5 years. A data set of about 100,000 bone voxels for each femur was collected. Bone density was observed by dint of an osteodensitometric computer program. The median results were shown in seven regions of interest (ROI) around the prosthesis stem, according to Gruen. Results The statistical analysis of the six cases after 60 months with respect to the postoperative control demonstrated a significantly lower density in ROI 2 (−125.5HU, P = 0.014), ROI 3 (−116.7HU, P = 0.023), ROI 4 (−54.5HU, P = 0.023), ROI 5 (−90.9HU, P = 0.014) and ROI 6 (−104.9HU, P = 0.014). Maximum density decrease was observed in ROI 2 and 3. The statistical analysis of the six cases after 60 months with respect to the 24 months control demonstrated a significantly lower density in ROI 2 (−62.6HU, P = 0.014), ROI 5 (−62.9HU, P = 0.023). There was a density decrease in ROI 3, 4, 6, 7 which was not significant and a slight increase in ROI 1. Conclusion To our knowledge, this is the first collection of fully prospective 5 years 3D periprosthetic density data. The CT method used in the study presented here measures three-dimensionally, while the frequently used DEXA (dual X-ray absorptiometry) method measures two-dimensionally. The data are also unique as they are suitable for direct patient-specific 3D finite element meshing and biomechanical calculation. They can be graphically post-processed in order to obtain cross-sectional or 3D displays of density patterns.     

Cementless modular hip revision arthroplasty using the MRP Titan Revision Stem: outcome of 79 hips after an average of 4 years’ follow-up

Introduction As primary total hip replacements (THRs) become more common in older patients and younger, physically active patients, the number of revision arthroplasties will also increase. Femoral bone loss, joint instability and possible infections are a challenge for a surgeon performing revision arthroplasty of the hip. The severe proximal femoral bone loss indicates the use of revision stems with a distal fixation.Materials and methods In this study the clinical and radiological outcomes of 79 cementless stem revisions using the MRP Titan Revision Stem with an average follow-up time of 4 years were prospectively examined.Results The Harris Hip Score improved from preoperative 50.8±25.2 to postoperative 86.8±13.2. In all cases healing of bony defects could be found. For stem diameters larger than 17 mm, atrophy of the proximal femur and non-progressive radiolucent lines in zones 1 and 7 according to Gruen were detected. No disadvantages or complications of the Morse taper junctions were observed, and no osteolysis was detected in this region. Primary stable fixation was achieved in all but two cases. Three cases were revised again due to periprosthetic fracture (1) and persisting infection (2).Conclusion Given the encouraging results with the MRP Titan Revision Stem, the principle of uncemented diaphyseal fixation appears to solve most of the technical problems in cases of significant bone loss and obviously offers good preconditions for bony restoration.     

Evaluation of clinical outcomes of cementless total hip arthroplasty in patients under 30 years of age

Background

Historically, performing a successful hip joint replacement in patients aged fewer than 30 years has been an orthopedic challenge. The newer generation of prostheses and surgical techniques has the potential to increase the longevity of implants. The purpose of this study was to evaluate the outcomes of cementless hip arthroplasty in patients aged fewer than 30 years.

Materials and methods

In this cross-sectional study, 41 patients (46 hips) were studied with a mean age of 24, 4 (from 17 to 30 years) of whom underwent cementless metal–polyethylene hip arthroplasty from 2004 to 2007. The Harris hip score (HHS) was used to assess the functional consequences. Patients were followed up in terms of early complications (thrombophlebitis of the lower limbs, dislocation, hematoma and infection) and late complications (aseptic loosening, dislocation and reoperation) at weeks 3 and 6, at 3 and 6 months, 1 year after surgery and annually thereafter.

Results

Patients were followed for an average of 5 years and 2 months (from 51 to 82 months). One early complication (symptomatic thrombophlebitis) and one late dislocation (2.2 %) were observed. There were no cases of aseptic loosening or osteolysis at the end of follow-up. The preoperative HHS was 59.6 (from 41 to 76), which rose to 82 and 83.5 after the 1-year and final follow-up, respectively, which was a significant increase.

Conclusions

Hip arthroplasty using a new generation of cementless proximal porous prosthesis with resistant polyethylene to cover the joint surfaces in patients aged fewer than 30 years is satisfactory and is accompanied by low complications.     

No detrimental effect of ligament balancing on functional outcome after total knee arthroplasty: a prospective cohort study on 129 mechanically aligned knees with 3 years’ follow-up

Background and purpose — In the classical mechanical alignment technique, ligament balancing is considered a prerequisite for good function and endurance in total knee arthroplasty (TKA). However, it has been argued that ligament balancing may have a negative effect on knee function, and some authors advocate anatomic or kinematic alignment in order to reduce the extent of ligament releases. The effect of the trauma induced by ligament balancing on functional outcome is unknown; therefore, the aim of this study was to investigate this effect.

Patients and methods — 129 knees (73 women) were investigated. Mean age was 69 years (42–82), and mean BMI was 29 (20–43). Preoperatively 103 knees had a varus deformity, 21 knees had valgus deformity, and 5 knees were neutral. The primary outcome measure was the Knee injury and Osteoarthritis Outcome Score (KOOS). Secondary outcome measures were the Oxford Knee Score (OKS) and patient satisfaction (VAS). All ligament releases were registered intraoperatively and outcome at 3 years’ follow-up in knees with and without ligament balancing was compared

Results — 86 knees were ligament balanced and 43 knees were not. Ligament-balanced varus knees had more preoperative deformity than varus knees without ligament balancing (p = 0.01). There were no statistically significant differences in outcomes between ligament-balanced and non-ligament-balanced knees at 3 years’ follow-up. No correlation was found between increasing numbers of soft tissue structures released and outcome.

Interpretation — We did not find any negative effect of the trauma induced by ligament balancing on knee function after 3 years.     

Improvement in range of movement after total knee replacement: do patients realize?

Introduction

This study was an attempt to see if patients can detect any change in the range of movement after a knee replacement and how much can the surgeon rely upon the patient’s self-assessment.

Materials and methods

One hundred and forty-two patients with arthritic knees who were waiting for total knee replacement (TKR) were chosen and range of movement (ROM) of their arthritic knee was measured. All these patients were called back into clinics for regular follow-up after TKR but only 112 attended. Their ROM was measured and all of them were asked whether they felt that the ROM of their knee had improved after replacement. The measurements and their answers were recorded.

Results

Of the 112 patients, 78 (70%) felt that ROM had improved, 32 (28%) felt that ROM did not improve and 2 (2%) of them were not sure. Our measurements showed that only 38 (34%) patients had improved ROM whereas 74 (66%) had no improvement, in some cases, decreased ROM after TKR. On comparing the patients’ assessment to our measurements, it was found that only 35 patients (31%) were right in their self-assessment whereas 75 patients (67%) were wrong.

Conclusion

We conclude that patients overestimate the change in ROM after knee replacement. An improvement in knee pain following TKR appears to have a positive influence on the patient’s perception of change in knee ROM.     

Total knee arthroplasty at 15–17 years: Does implant design affect outcome?

Purpose

A study was conducted to compare minimum 15-year survivorship and outcome of the Genesis I and II implants for total knee arthroplasty (TKA).

Methods

We retrospectively reviewed 245 consecutive TKA implanted between January 1995 and October 1997. Genesis I was implanted in 156 knees and Genesis II in 89 knees.

Results

At 15–17 years, 75 patients (31 %) had died, 28 patients (11 %) were lost to follow-up and 11 TKA were revised (4.6 %), including ten Genesis I (6.4 %) and one Genesis II (1.1 %); 131 TKA (53 %) were available for follow-up. Cumulative survivorship was 92.4 % at 15.7 years. Survival in patients <69 years at surgery was lower (88.0 %) compared with patients ≥69 years (98.5 %; p = 0.023). In patients <69 years, Genesis I survival (84.3 %) was worse compared with Genesis II (97.1 %) (p = 0.018). Polyethylene (PE) Insert thickness ≤11 mm had significantly better survivorship (97.1 %) compared with PE >11 mm (56.7 %) (p < 0.0001)

Conclusions

At a minimum of 15 years, the overall (92.4 %) survivorship of Genesis TKA was good, with excellent (98.1 %) survivorship of the Genesis II design. Revision rates were higher with Genesis I in the younger age group and with insert thickness >11 mm, possibly due to longer shelf life of less frequently used sizes.     

The use of a dual-articulation acetabular cup system to prevent dislocation after primary total hip arthroplasty: analysis of 384 cases at a mean follow-up of 15 years

The concept of a dual articulation acetabular cup was developed by Prof. Bousquet in 1974. This concept has been shown to provide high stability after revision and primary total hip arthroplasty. The aim of our study was to evaluate the incidence of prosthetic instability in a consecutive homogeneous series of 384 primary dual mobility cups. Incidence of instability and implant survival were evaluated. Mean follow-up was 15.3 years (range, 12–20). There was no early or late instability. On the acetabular side there were 13 aseptic loosenings, 14 intraprosthetic dislocations, and seven polyethylene wear cases that required replacement of the liner. The cumulative survival rate of the dual-articulation acetabular cup using surgical revision for aseptic loosening as the endpoint was 95.9% ± 4.1% at 18 years postoperatively. Our series proves the good long term behaviour of dual-articulation acetabular components in primary arthroplasty. Their excellent survivorship rate and the absence of episodes of prosthetic instability increase our confidence in this concept.

---

Résumé  Le concept de cupule à double mobilité a été inventé par le Professeur Gilles BOUSQUET en 1974. Ce concept a permis de mettre en évidence une importante stabilité des hanches, notamment après révision mais également dans les prothèses totales de hanches de première intention. Le but de cette étude est d’évaluer l’incidence et l’instabilité sur une série homogène consécutive de 384 hanches traitées avec cupule à double mobilité. Le taux d’instabilité des implants sur les patients survivants a été évalué. Le suivi moyen a été de 15,3 ans (de 12 à 20 ans) au plus long recul, il n’y a aucune instabilité ni primaire, ni tardive. Par contre, il existe 13 descellements aseptiques acétabulaires, 14 luxations intra prothétiques, 7 usures du polyéthylène qui ont nécessité un remplacement du PE. Le taux de survie cumulé de cette cupule à double mobilité est de 95,9% ± à 18 ans si l’on prend comme critère la révision pour descellement aseptique. Cette série prouve le bon devenir à long terme de cette articulation dans les prothèses totales primaires, avec un excellent taux de survie et l’absence de phénomènes de luxation inhérentes à ce concept.

     

Does obesity influence the clinical outcome at five years following total knee replacement for osteoarthritis?

A total of 370 consecutive primary total knee replacements performed for osteoarthritis were followed up prospectively at 6, 18, 36 and 60 months. The Knee Society score and complications (perioperative mortality, superficial and deep wound infection, deep-vein thrombosis and revision rate) were recorded. By dividing the study sample into subgroups based on the body mass index overall, the body mass index in female patients and the absolute body-weight. The outcome in obese and non-obese patients was compared. A repeated measures analysis of variance showed no difference in the Knee Society score between the subgroups. There was no statistically-significant difference in the complication rates for the subgroups studied. Obesity did not influence the clinical outcome five years after total knee replacement.     

Cementless cup fixation in total hip arthroplasty after 5–8 years

A series of 199 total hip arthroplasties was performed using a porous-coated, hemispherical press-fit acetabular cup. At a mean follow-up of 91.5 months 158 cups were available for clinical and radiological review. The mean age of the patients at the time of the index arthroplasty was 62.5 years. The mean Harris Hip score at final follow-up was 87.3. No shells were revised although eccentric polyethylene wear prompted liner replacement in two cases. Osteolysis was noted in six cases but predominantly in relation to the femoral stem. Focal pelvic osteolytic lesions were rare. All the cups were classified as stable on radiography.