Higher Risk Of Revision Research Articles

Predictors for venous sinus stent retreatment in patients with idiopathic intracranial hypertension

BackgroundVenous sinus stenting for dural sinus stenoses is an emerging alternative to cerebrospinal fluid diversion in cases of medically refractory idiopathic intracranial hypertension. Juxta-stent ‘re-stenoses’ have been reported and managed...

What is the lifetime risk of revision for patients undergoing total hip arthroplasty? a 40-year observational study of patients treated with the Charnley cemented total hip arthroplasty.

The purpose of this study was to determine the lifetime risk of revision surgery for patients undergoing Charnley cemented total hip arthroplasty (THA), with 40-year follow up, using death as a competing risk. We retrospectively reviewed 2000 cemented Charnley THAs, with 51 living hips available at 40 years. The cumulative risk of revision or removal for any reason was 13% (95% confidence interval (CI) 12 to 15). Patients aged under 50 years at the time of surgery had a 35% (95% CI 28 to 42) risk of revision or removal for any reason (Hazard Ratio (HR) 3.6; 95% CI 2.5 to 5.2; p<0.001), patients 50 to 59 years old had a 20% risk (95% CI 16 to 24) (HR 2.1; 95% CI 1.5 to 2.8; p < 0.0001), patients aged 60 to 69 years had a 9% risk (95% CI 7 to 11) (reference point), and patients ≥ 70 years old had a 5% risk (95% CI 4 to 7) (HR 0.96; 95% CI 0.6 to 1.5; p = 0.86) during their lifetime. Men had a higher risk of revision or removal for any reason (HR 2.1; 95% CI 1.7 to 2.7; p < 0.001). With almost all the patients in this series followed up till either death or revision, we have been able to develop a 'rule of thumb' for lifetime likelihood of revision or implant removal for the Charnley THA: one in three for patients < 50 years, one in five for patients 50 to 59 years, one in ten for patients 60 to 69 years, and one in 20 for patients ≥ 70 years. The results provide a benchmark for comparison of outcomes, for the newer designs of THA. Cite this article: Bone Joint J 2016;98-B:1436-40.

Three-year outcomes of intracapsular femoral neck fractures fixed with sliding hip screws in adults aged under sixty-five years

IntroductionIntracapsular femoral neck fractures remain associated with high rates of post-traumatic femoral head necrosis, non-union, and revision surgery. AimOur aim was to identify factors associated with revision surgery in intracapsular femoral neck fractures treated with sliding hip screws (SHS) in adults aged <65 years. Patients and methodsConsecutive admissions were identified retrospectively from the Royal Victoria Hospital, Belfast, which was the largest volume hospital on the National Hip Fracture Database. Of 2201 hip fractures between 1st August 2008 and 31st December 2010, 97 (4%) intracapsular fractures treated with SHS in adults <65 years were followed for a mean of 2.9 years (range 0–6.6). ResultsTwenty-one (22%) hips were revised to arthroplasty. Avascular necrosis developed in 28 (29%) femoral heads. Eight (8%) fractures proceeded to non-union. Displaced fractures (p<0.001, Fisher’s exact [FE]), posterior comminution (p=0.049, FE), chronic respiratory disease (p=0.006, FE) and residual distraction (p=0.011, χ2) were associated with revision to arthroplasty. Multiple regression found displaced fractures (p=0.006) and chronic respiratory disease (p=0.017) significant; in the latter 4 of 6 were revised (67%), including all four patients with chronic obstructive pulmonary disease (COPD). Eleven (11%) individuals required walking aids before injury, which rose to 34 (35%) at one year (p<0.0001, χ2). Eighty-nine (92%) individuals could walk alone outdoors before injury, but only 76 (78%) at one year (p=0.009, χ2). ConclusionsDisplaced fractures in individuals with chronic respiratory disease should be considered high risk for revision to arthroplasty. Posterior cortex deficiency should be evaluated prior to choice of operation. Fracture biology and revascularisation play a greater role than operation timing. A significant proportion of individuals do not recovery pre-morbid mobility by one year.

What Risks are Associated with Primary THA in Recipients of Hematopoietic Stem Cell Transplantation?

As patients who receive hematopoietic stem cell transplantation are at increased risk of avascular necrosis (AVN) and subsequent degenerative arthritis, THA may be considered in some of these patients, particularly as overall patient survival improves for patients undergoing stem-cell transplants. Patients receiving hematopoietic stem cell transplantation theoretically are at increased risk of experiencing complications, infection, and poorer implant survivorship owing to the high prevalence of comorbid conditions, immunosuppressive therapy regimens including corticosteroids, and often low circulating hematopoietic cell lines; however, there is a paucity of studies elucidating these risks. We asked: (1) What is the overall mortality of patients with hematopoietic stem cell transplantation who have undergone THA? (2) What is the complication rate for these patients? (3) What are the revision and reoperation rates and implant survivorship for these patients? Between 1999 and 2013, we performed 42 THAs in 36 patients who underwent stem-cell transplants. Other than those who died, all were available for followup at a minimum of 2 years; of the patients whose procedures were done more than 10 years ago and who are not known to have died, two (5%) had not been seen in the last 5 years and so are considered lost to followup. All patients underwent thorough evaluation by the transplant team before arthroplasty; general contraindications included active medical comorbidities or evidence of unstable end-organ damage, active rejection, and critically low circulating hematopoietic cell lines. Underlying primary diseases leading to hematopoietic stem cell transplantation included lymphoma (14/42; 33%), plasma cell disorders (10/42; 24%), leukemia (9/42; 21%), and amyloidosis (3/42; 7%). Complications, reoperations, revisions, and implant and patient survivorship, were recorded from chart review and data from the institutional total joint registry. Mean followup was 5 years (range, 2-15 years). Patient survivorship free of mortality was 91% (95% CI, 81%-100%) and 82% (95% CI, 68%-96%) at 2 and 5 years, respectively. Complications occurred in four of 42 THAs (10%); these complications included an intraoperative fracture and a venous thromboembolism. Revisions occurred in two of 42 (5%) THAs; there were no reoperations. Implant survivorship free of component revision for any reason or implant removal accounting for death as a competing risk was 93% (95% CI, 83%-100%) at 5 years. With appropriate medical evaluation and comanagement by transplant specialists, carefully selected patients with hematopoietic stem cell transplants may undergo elective primary THA, although complications do occur in this relatively fragile patient population. Although implant survivorship was modest at 93% at 5 years, there was not a high risk of revision for infection. Improved outcomes for these patients may be expected as their medical management advances and additional comparative studies may clarify other important patient factors. Level IV, therapeutic study.

Type and frequency of healthcare encounters can predict poor surgical outcomes in anterior cruciate ligament reconstruction patients

BackgroundSeveral challenges are associated with collecting clinically meaningful post-operative outcomes. The widespread implementation of electronic medical records (EMR) offers a new opportunity to evaluate surgical outcomes using routinely collected data in these systems. This study evaluated whether surgical outcomes can be ascertained from EMR’s hospital and outpatient encounters. Specifically, we evaluated anterior cruciate ligament reconstructions (ACLR) outcomes. MethodsA retrospective cohort study of 6985 ACLRs performed between 2/2005-9/2012 was conducted. Patient encounters during days 1–90 and days 91–180 after ACLR surgery were the exposures of interest. Nine hospital and eight outpatient encounter types were evaluated. The main endpoint of the study was revision surgery six months after ACLR. ResultsThe cohort was 66.7% male, the mean age was 28 (standard deviation=11) years-old, and the incidence of revision was 1.5% (n=105). After adjustments, in days 1–90 post-ACLR, compared to patients with 0–4 orthopedic office visits, patients with 5–9 (hazard ratio (HR)=9.9, 95% confidence interval(CI), 4.3–23.2) and those with 10 or more (HR=13.8, 95%CI, 5.6–33.8) visits had a higher risk of revision. In days 91–180, patients with any outpatient hospital encounters (HR=2.5, 95%CI 1.4–4.5) had a higher risk of revision than patients without visits. Additionally, patients with 4–5 regular office visits (HR=3.8 times, 95%CI, 2.0–7.0) had a higher risk of revision surgery than those with 0–1 visits. DiscussionThe number of post-operative outpatient visits was associated with ACLR revision surgery. Using EMR encounters to assess surgical outcomes is a viable option for monitoring ACLR patients. The simple assessment of visit types and number of encounters alone can provide valuable information regarding the normal course of rehabilitation of a surgical patient and possible deviation from this normal course. In large cohorts of patients, this type of patient surveillance can assist surgeons with monitoring their patients.

Increased Risk of Postoperative Complications After Total Knee Arthroplasty in Patients With Previous Patellectomy

BackgroundFew studies have reported the results of total knee arthroplasty (TKA) in patients with previous patellectomy. The purpose of this study was to assess the risk of complications and survivorship of primary TKA in patients who previously had a patellectomy in comparison to those undergoing TKA with patellar resurfacing. MethodsThis was a historical cohort study and comprised 134 knees with previous patellectomy in a cohort of 17,946 primary TKA procedures at a single institution between 1985 and 2010. Multivariable Cox regression analyses were used to estimate the risk of complications and revisions in patients with previous patellectomy. ResultsWhen compared to TKA with patellar resurfacing, the risk of complications (hazards ratio: 1.38, 95% confidence interval: 1.05, 1.81) was significantly higher in post-patellectomy knees, but there was no difference in the risk of revisions (hazards ratio: 1.32, 95% confidence interval: 0.80, 2.18). There was no significant difference between the posterior-stabilized and cruciate-retaining designs in terms of both complications and revisions (P > .05). The most common complications in post-patellectomy knees were instability, delayed healing, and infection. ConclusionTKA patients with previous patellectomy have a higher risk of complications but not a higher risk of revisions.

Is Sternal Revision after Open Heart Surgery Predictable? Development of a Risk Assessment Score for Reoperation Caused by Sternal Wound Infection

Objectives: Despite the progress of surgical technique and postoperative wound care management, deep sternal wound infection (DSWI) is still associated with high mortality and morbidity. Diagnosis is often delayed and therapy is complicated by late and gradual onset of wound healing disturbances, even after discharge from hospital. The aim of this study was to develop a postoperative clinical tool to identify patients with high risk for sternal revision caused by sternal wound infection.

Age-Related Risk Factors for Revision Anterior Cruciate Ligament Reconstruction

Background: It is not clear whether risk factors for revision anterior cruciate ligament reconstruction (ACLR) are the same throughout patients’ lives. Purpose: To assess (1) the risk of revision ACLR by age and (2) age-specific risk factors for revision ACLR. Study Design: Cohort study; Level of evidence, 2. Methods: A cohort study using patients having undergone primary ACLR who were registered in the Kaiser Permanente ACLR Registry (February 2005 to June 2013) was conducted. Aseptic revision was the main endpoint. Age was evaluated as a risk factor for revision. The cohort was stratified into 4 age groups: <21, 21-30, 31-40, and >40 years. Graft type, sex, body mass index (BMI), and race were assessed as revision risk factors within each group. Survival analyses were conducted. Results: Of the 21,304 patients evaluated, 7026 (33%) patients were aged <21 years, 5762 (27%) were 21-30 years, 4656 (22%) were 31-40 years, and 3860 (18%) were >40 years. Allografts were used in 8671 (41%) patients, hamstring autografts in 6823 (32%), and bone–patellar tendon–bone (BPTB) autografts in 5260 (25%). The 5-year revision probability was highest in patients <21 years old (9.0%; 95% CI, 8.0%-10.1%) and lowest in those >40 years old (1.9%; 95% CI, 1.3%-2.7%). Compared with patients aged >40 years, the adjusted revision risk for patients aged <21 years was 7.76 (95% CI, 5.52-10.90). In patients aged <21 years, a lower revision risk was seen in female patients (hazard ratio [HR], 0.76; 95% CI, 0.61-0.93) compared with male patients, patients with a BMI of 30-35 kg/m2 (HR, 0.75; 95% CI, 0.59-0.95) and BMI >35 kg/m2 (HR, 0.49; 95% CI, 0.34-0.70) compared with those with a BMI <30 kg/m2, and black patients (HR, 0.55, 95% CI, 0.36-0.85) compared with white patients. Sex, BMI, and race were not associated with the risk of revision in older patients. In patients ≤40 years old, those with allografts had a higher risk of revision than those with BPTB autografts (HR, 2.69, 2.35, and 3.04 for patients aged <21, 21-30, and 31-40 years, respectively). Patients <21 years old with hamstring autografts had a 1.61 times (95% CI, 1.20-2.17) higher risk of revision than did patients with BPTB autografts; these differences were not identified in older patients. Conclusion: Age at the time of ACLR surgery is a strong risk factor for revision ACLR. Other risk factors for revision ACLR, such as graft type, sex, race, and BMI, may vary in strength and significance over a patient’s life. Understanding the age-related risk factors associated with revision ACLR may help with appropriate patient counseling and optimal graft choice when performing ACLR.

Implant Optimisation for Primary Hip Replacement in Patients over 60 Years with Osteoarthritis: A Cohort Study of Clinical Outcomes and Implant Costs Using Data from England and Wales.

BackgroundHip replacement is one of the most commonly performed surgical procedures worldwide; hundreds of implant configurations provide options for femoral head size, joint surface material and fixation method with dramatically varying costs. Robust comparative evidence to inform the choice of implant is needed. This retrospective cohort study uses linked national databases from England and Wales to determine the optimal type of replacement for patients over 60 years undergoing hip replacement for osteoarthritis.Methods and FindingsImplants included were the commonest brand from each of the four types of replacement (cemented, cementless, hybrid and resurfacing); the reference prosthesis was the cemented hip procedure. Patient reported outcome scores (PROMs), costs and risk of repeat (revision) surgery were examined. Multivariable analyses included analysis of covariance to assess improvement in PROMs (Oxford hip score, OHS, and EQ5D index) (9159 linked episodes) and competing risks modelling of implant survival (79,775 procedures). Cost of implants and ancillary equipment were obtained from National Health Service procurement data.ResultsEQ5D score improvements (at 6 months) were similar for all hip replacement types. In females, revision risk was significantly higher in cementless hip prostheses (hazard ratio, HR = 2.22, p<0.001), when compared to the reference hip. Although improvement in OHS was statistically higher (22.1 versus 20.5, p<0.001) for cementless implants, this small difference is unlikely to be clinically important. In males, revision risk was significantly higher in cementless (HR = 1.95, p = 0.003) and resurfacing implants, HR = 3.46, p<0.001), with no differences in OHS. Material costs were lowest with the reference implant (cemented, range £1103 to £1524) and highest with cementless implants (£1928 to £4285).Limitations include the design of the study, which is intrinsically vulnerable to omitted variables, a paucity of long-term implant survival data (reflecting the duration of data collection), the possibility of revision under-reporting, response bias within PROMs data, and issues associated with current outcome scoring systems, which may not accurately reflect level of improvement in some patients.ConclusionsCement fixation, using a polyethylene cup and a standard sized head offers good outcomes, with the lowest risks and at the lowest costs. The most commonly used cementless and resurfacing implants were associated with higher risk of revision and were more costly, while perceptions of improved function and longevity were unsupported.

Revision Risk After Allograft Anterior Cruciate Ligament Reconstruction

Background: Allograft tissue is a common graft choice for anterior cruciate ligament reconstruction (ACLR). Allograft sterilization methods vary widely across numerous commercial tissue vendors. Multiple studies, despite being limited in sample size, have suggested a higher rate of clinical failure associated with the use of allograft tissue in ACLR when compared with autograft. Purpose: To examine the association of graft processing techniques, patient characteristics, and graft type with risk of revision surgery after allograft ACLR. Study Design: Cohort study; Level of evidence, 3. Methods: A retrospective cohort study was conducted that used an integrated United States health care system’s ACLR registry to identify primary unilateral cases in which allografts were used. Aseptic revision was the endpoint of the study. Allograft type, processing methods (irradiation dose, AlloWash, AlloTrue, BioCleanse), and graft donor age were assessed as potential risk factors for revision, with adjustment for patient age, sex, and body mass index (BMI) by use of survival analysis. Hazard ratios (HR) and 95% confidence intervals (CIs) were calculated. Results: A total of 5968 primary ACLR cases with allograft were included in the study, of which 3688 (61.8%) were male patients. The median age of the cohort at the time of surgery was 34.1 years (interquartile range, 24.1-42.9 years). The mean time to follow-up (±SD) was 2.1 ± 1.5 years. There were 3751 (62.9%) allograft ACLRs using soft tissue, 1188 (19.9%) with Achilles tendon, and 1029 (17.2%) with bone–patellar tendon–bone (BPTB). Graft processing groups included BioCleanse (n = 367), AlloTrue or AlloWash (n = 2278), irradiation greater than 1.8 Mrad (n = 1146), irradiation up to 1.8 Mrad (n = 3637), and no irradiation (n = 1185). There were 156 (2.6%) aseptic revisions. After adjustment for patient age, sex, and BMI, the use of BioCleanse (HR = 2.45; 95% CI, 1.36-4.40) and irradiation greater than 1.8 Mrad (HR = 1.64; 95% CI, 1.08-2.49) were associated with a higher risk of revision when compared with all other methods of processing. BPTB allografts were at higher risk of revision (HR = 1.79; 95% CI, 1.20-2.66) when compared with soft tissue allografts. Conversely, with every 5-year increase in age, the risk of revision was 0.67 (95% CI, 0.61-0.73) times lower. Male patients were found to be at higher risk of revision when compared with females (HR = 1.47; 95% CI, 1.04-2.07). The use of AlloWash or AlloTrue processing, patient BMI, and graft donor age did not affect revision rate significantly. Conclusion: In the largest known study of its kind examining outcome after primary allograft ACLR, graft irradiation greater than 1.8 Mrad, BioCleanse graft processing, younger patient age, male patients, and BPTB allograft were all associated with a higher risk of clinical failure and subsequent revision surgery.

CORR Insights(®): Anterior and Anterolateral Approaches for THA Are Associated With Lower Dislocation Risk Without Higher Revision Risk.

T he direct anterior approach for THA has garnered substantial interest among total joint surgeons. A Google search for ‘‘anterior approach hip’’ returned 1,190,000 matches. The most common claims of superiority of direct anterior approach include: Decreased length of hospital stay, quicker rehabilitation, less blood loss, shorter surgery, less postoperative pain, lower risk of dislocation, more natural return to function and activity, and shorter incisions. In fact, one manufacturer’s website (http://www. aboutstryker.com/hip/procedures/procedures-daa.php) emphasizes that the new approach can be done through a three or four inch incision, compared to eight to 12 inches for a moretraditional approach, which the manufacturer also says ‘‘requires a significant disturbance of the joint and connecting tissues.’’ Ironically, direct anterior is considered a new approach even though the anterior approach (which is the lower limb of a classic Smith-Peterson approach) was described in 1949 and was used during my residency training and musculoskeletal oncology training (1979–1986). The approach was recommended for patients with higher risk of dislocation (dementia, neuromuscular disorders) and was used for treatment of benign and malignant disease of the hip. In practice, I have also used it in cases of simultaneous bilateral THA.

Anterior and Anterolateral Approaches for THA Are Associated With Lower Dislocation Risk Without Higher Revision Risk.

Lack of consensus continues regarding the benefit of anteriorly based surgical approaches for primary total hip arthroplasty (THA). The purpose of this study was to evaluate the risk of aseptic revision, septic revision, and dislocations for various approaches used in primary THAs from a community-based healthcare organization. (1) What is the incidence of aseptic revision, septic revision, and dislocation for primary THA in a large community-based healthcare organization? (2) Does the risk of aseptic revision, septic revision, and dislocation vary by THA surgical approach? The Kaiser Permanente Total Joint Replacement Registry was used to identify primary THAs performed between April 1, 2001 and December 31, 2011. Endpoints were septic revisions, aseptic revisions, and dislocations. The exposure of interest was surgical approach (posterior, anterolateral, direct lateral, direct anterior). Patient, implant, surgeon, and hospital factors were evaluated as possible confounders. Survival analysis was performed with marginal multivariate Cox models. Hazard ratios (HRs) and 95% confidence intervals (CIs) are reported. A total of 42,438 primary THAs were available for analysis of revision outcomes and 22,237 for dislocation. Median followup was 3 years (interquartile range, 1-5 years). The registry's voluntary participation is 95%. The most commonly used approach was posterior (75%, N = 31,747) followed by anterolateral (10%, N = 4226), direct anterior (4%, N = 1851), and direct lateral (2%, N = 667). During the study period 785 hips (2%) were revised for aseptic reasons, 213 (0.5%) for septic reasons, and 276 (1%) experienced a dislocation. The revision rate per 100 years of observation was 0.54 for aseptic revisions, 0.15 for septic revisions, and 0.58 for dislocations. There were no differences in adjusted risk of revision (either septic or aseptic) across the different THA approaches. However, the anterolateral approach (adjusted HR, 0.29; 95% CI, 0.13-0.63, p = 0.002) and direct anterior approach (adjusted HR, 0.44; 95% CI, 0.22-0.87, p = 0.017) had a lower risk of dislocation relative to the posterior approach. There were no differences in any of the outcomes when comparing the direct anterior approach with the anterolateral approach. Anterior and anterolateral surgical approaches had the advantage of a lower risk of dislocation without increasing the risk of early revision. Level III, therapeutic study.

CORR Insights ®: Metal-on-conventional total hip arthroplasty bearing surfaces have a higher risk of revision than metal-on-highly crosslinked polyethylene: results from a US registry.

H ighly crosslinked polyethylene (XLPE) has essentially supplanted conventional polyethylene for use in total hip arthroplasty (THA) during the past decade. There now exists good evidence to demonstrate a clear reduction in femoral head penetration (and presumably polyethylene wear) and periprosthetic osteolysis associated with the use XLPE compared to conventional polyethylene in THA [2, 3]. While the annual reports of Australian Orthopaedic Association National Joint Replacement Registry continue to show the clinical benefits of XLPE (demonstrating a reduction in revision rates) [1], other investigators have not demonstrated a clear reduction in revision rates with the use of XLPE at mid-term followup [4]. The current study by Paxton and colleagues attempts to demonstrate the clinical benefits resulting from the use of XLPE compared to conventional polyethylene through the analysis of a large US-based patient database. Their findings demonstrate that, for two specific implant designs, the revision rate was significantly decreased for XLPE compared to the use of conventional polyethylene. Therefore, this work essentially confirms the experience reported by the Australian Orthopaedic Association National Joint Replacement Registry during the past decade. While important work, this study is limited by the observational nature of the study, inherent to all registry or database analysis, and only provides information about two specific hip designs (both of which having been replaced by more recent designs by their respective manufacturers). Furthermore, analysis of this type does not provide any radiological, functional or patient-derived outcomes This CORR Insights is a commentary on the article ‘‘Metal-on-conventional Total Hip Arthroplasty Bearing Surfaces Have a Higher Risk of Revision Than Metal-on-highly Crosslinked Polyethylene: Results From a US Registry’’ by Paxton and colleagues available at: DOI: 10.1007/s11999-014-4105-9 The author certifies that he, or any member of his immediate family, has no funding or commercial associations (eg, consultancies, stock ownership, equity interest, patent/ licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article. All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research editors and board members are on file with the publication and can be viewed on request. The opinions expressed are those of the writers, and do not reflect the opinion or policy of CORR or the Association of Bone and Joint Surgeons. This CORR Insights comment refers to the article available at DOI: 10.1007/s11999-0144105-9

Metal-on-conventional polyethylene total hip arthroplasty bearing surfaces have a higher risk of revision than metal-on-highly crosslinked polyethylene: results from a US registry.

Although studies have reported lower radiological wear in highly crosslinked polyethylene (HXLPE) versus conventional polyethylene in total hip arthroplasty (THA), there is limited clinical evidence on the risk of revision of these polyethylene THA bearing surfaces. We asked: (1) Do primary THAs with a metal-on-conventional polyethylene bearing surface have a higher risk of revision (all-cause or aseptic) than metal-on-HXLPE? (2) Is the risk of revision (all-cause or aseptic) higher for conventional polyethylene versus HXLPE when the effect of femoral and acetabular components is controlled for in prosthesis-specific analyses? The Kaiser Permanente's Total Joint Replacement Registry was used to identify metal-on-conventional polyethylene and metal-on-HXLPE primary THAs (N = 26,823) performed between April 2001 and December 2011. The registry has 95% voluntary participation and 8% were lost to followup during the 10-year study period. Endpoints of interest were all-cause and aseptic revisions. Descriptive statistics and marginal Cox regression models with propensity score adjustments were applied to compare risk of revision for metal-on-conventional polyethylene versus metal-on-HXLPE THAs and to evaluate two specific manufacturers' hip implant designs while controlling for femoral and acetabular components. Of the 26,823 THAs included in the study, 1815 (7%) were metal-on-conventional polyethylene and 25,008 (93%) were metal-on-HXLPE. At 7 years followup, the cumulative incidence of revision was 5.4% (95% confidence interval [CI], 4.4%-6.7%) for metal-on-conventional and 2.8% (95% CI, 2.6%-3.2%) for metal-on-HXLPE. There was a higher adjusted risk of all-cause (hazard ratio [HR], 1.75; 95% CI, 1.37-2.24; p < 0.001) and aseptic (HR, 1.91; 95% CI, 1.46-2.50; p < 0.001) revisions among metal-on-conventional polyethylene bearing surface hips compared with metal-on-HXLPE. Results were similar within manufacturer hip designs with the same femoral and acetabular components. Conclusions Metal-on-conventional polyethylene THA bearing surfaces have a higher risk of revision compared with metal-on-HXLPE bearing surfaces. Clinicians should consider the use of HXLPE when using a polyethylene bearing in THA. Level II, cohort study.

Outcome and risk of revision following shoulder replacement in patients with glenohumeral osteoarthritis

This thesis includes four studies focusing on the functional outcome, shoulder-specific quality of life and risk of revision following shoulder replacement in patients with glenohumeral osteoarthritis without symptomatic rotator cuff pathology. The Danish version of WOOS, translated according to international standardized guidelines, had substantial psychometric properties comparable to the original version. It is recommendable to use WOOS in the evaluation of patients with glenohumeral osteoarthritis treated with shoulder replacement. Data from DSR showed that the shoulder specific quality of life following total shoulder arthroplasty was superior to that of hemiarthroplasty (resurfacing hemiarthroplasty and stemmed hemiarthroplasty). The difference between stemmed hemiarthroplasty and resurfacing hemiarthroplasty was small and did not exceed the minimal clinically important difference. The revision rate following resurfacing hemiarthroplasty was surprisingly high compared with previous reports but there were no statistical significant differences in revision rate between arthroplasty designs. The shoulder specific quality of life and revision rate in patients under the age of 55 was worrying. The use of resurfacing hemiarthroplasty has relied on the results from case series only. The efficacy in the treatment of glenohumeral osteoarthritis has been promising but the CMS found in the randomized clinical trial indicate that the functional outcome may be inferior to that of stemmed hemiarthroplasty and less favourable than previously reported. However, the limited number of patients may have influenced the results and a larger definitive RCT is needed.Shoulder replacement is relevant and effective in the treatment of glenohumeral osteoarthritis; however, resurfacing hemiarthroplasty was associated with a poorer outcome and a higher risk of revision than previously assumed especially in patients under the age of 55. Based on data from this thesis, and based on existing knowledge, it seems like total shoulder arthroplasty should be preferred in the treatment of glenohumeral osteoarthritis. Shoulder replacement is rarely indicated in younger patients where other treatment options (e.g., physiotherapy; intraarticular injections of hyaluronate; and joint preserving surgery) should be considered until the efficacy of shoulder replacement has been more thoroughly documented.

FRI0216 Therapeutic Education and Functional Readaptation in Obese Patients on A Waiting List for Total Knee Replacement. A Case-Control Study

BackgroundStudies show patients with knee osteoarthritis (OA) on waiting list for total knee replacement (TKR) underused conservative treatment, did not adhere to clinical guidelines on knee OA management, and potentially...

Risk Factors for Total Hip Arthroplasty Aseptic Revision

The purpose of this study was to evaluate patient, operative, implant, surgeon, and hospital factors associated with aseptic revision after primary THA in patients registered in a large US Total Joint Replacement Registry. A total of 35,960 THAs registered from 4/2001–12/2010 were evaluated. The 8-year survival rate was 96.7% (95% CI 96.4%–97.0%). Females had a higher risk of aseptic revision than males. Hispanic and Asian patients had a lower risk of revision than white patients. Ceramic-on-ceramic, ceramic-on-conventional polyethylene, and metal-on-conventional polyethylene bearing surfaces had a higher risk of revision than metal-on-highly cross-linked polyethylene. Body mass index, health status, diabetes, diagnosis, fixation, approach, bilateral procedures, head size, surgeon fellowship training, surgeon and hospital volume were not revision risk factors.

Cost-effectiveness of unicondylar versus total knee arthroplasty: a Markov model analysis

Unicondylar knee arthroplasty (UKA) is believed to lead to less morbidity and enhanced functional outcomes when compared with total knee arthroplasty (TKA). Conversely, UKA is also associated with a higher revision risk than TKA. In order to further clarify the key differences between these separate procedures, the current study assessing the cost-effectiveness of UKA versus TKA was undertaken. A state-transition Markov model was developed to compare the cost-effectiveness of UKA versus TKA for unicondylar osteoarthritis using a Belgian payer's perspective. The model was designed to include the possibility of two revision procedures. Model estimates were obtained through literature review and revision rates were based on registry data. Threshold analysis and probabilistic sensitivity analysis were performed to assess the model's robustness. UKA was associated with a cost reduction of €2,807 and a utility gain of 0.04 quality-adjusted life years in comparison with TKA. Analysis determined that the model is sensitive to clinical effectiveness, and that a marginal reduction in the clinical performance of UKA would lead to TKA being the more cost-effective solution. UKA yields clear advantages in terms of costs and marginal advantages in terms of health effects, in comparison with TKA.

Patient Selection in Outpatient and Short-Stay Total Knee Arthroplasty

The purpose of the current study is to identify patients who are at high risk for rehospitalization, revision, complications, and mortality after outpatient and short-stay total knee arthroplasty (TKA). The Medicare 5% limited data set sample was used to identify patients with a TKA procedure who were treated in an outpatient setting or who were discharged within 1 or 2 days in the hospital setting. Rehospitalization risk increased with higher Charlson score (i.e., poorer health status), older patients, inpatients (vs. outpatients), patients not receiving a femoral nerve block, earlier (vs. recent) year of surgery, and those with a recent history of heart failure. The findings of this study suggest that existing comorbidities, particularly heart failure, have the greatest effect on event risk after outpatient and short-stay TKA. The information obtained from this study should assist with patient selection for TKA performed on an outpatient basis.

Joint Registries as Continuous Surveillance Systems: The Experience of the Catalan Arthroplasty Register (RACat)

The aim was to present results on prosthesis performance in Catalonia for the period 2005-2010. All publicly funded hospitals submit in an electronic format data on hip and knee arthroplasties: patients' insurance identification number, hospital, joint (hip/knee), type of arthroplasty (primary/revision), side (right/left), date of surgery and prosthesis (manufacturer name and catalogue number). A standard survival analysis based on Kaplan-Meier estimation was carried out. Fifty-two hospitals have sent information to the RACat which has data on 36,951 knee and 26,477 hip arthroplasties. Cumulative prostheses revision risks at 3 years were 3.3% (95% CI: 3.1-3.6) for knee, 2.9% (95% CI: 2.5-3.3) for total hip and 2.5% (95% CI: 2.0-3.1) for partial hip. When compared to other registries a higher risk of revision was observed.