Incidence of and Risk Factors for 30-Day Readmission Following Elective Primary Total Joint Arthroplasty: Analysis From the ACS-NSQIP

Recently, the government has moved towards public reporting of 30-day readmission rates after elective primary total knee (TKA) and total hip arthroplasty (THA). We identified 11,814 and 8105 patients who underwent primary TKA and THA from the 2011 ACS NSQIP. Overall readmission rates within 30-days of surgery were 4.6% for TKA and 4.2% for THA. Complications associated with readmission were predominantly wound infections, sepsis, thromboembolic, cardiac, and respiratory related. In TKA, multivariate analysis identified age (P = 0.002), male gender (P = 0.03), cancer history (P = 0.008), elevated BUN (P = 0.002), a bleeding disorder (P < 0.001) and high ASA class (P < 0.001) as predictors of readmission. In THA, obesity (P = 0.008), steroid use (P = 0.037), a bleeding disorder (P = 0.002), dependent functional status (P = 0.022), and high ASA class (P < 0.001) predicted readmission. Understanding characteristics associated with readmission will be essential for equitable patient risk stratification.     

Changes in Blood Coagulation–Fibrinolysis Markers By Pneumatic Tourniquet During Total Knee Joint Arthroplasty With Venous Thromboembolism

This study investigated changes in blood coagulation–fibrinolysis markers during total knee arthroplasty (TKA). Preoperative 16-row multidetector row computed tomography (MDCT) revealed no asymptomatic venous thromboembolism (VTE) in the 42 patients recruited. Using MDCT postoperatively, patients were divided into thrombus (asymptomatic VTE, 19 patients) and no-thrombus (23 patients) groups. Blood taken at intervals before and after pneumatic tourniquet release revealed increased plasminogen activator inhibitor type-1 (PAI-1) at 30 s for both groups and at 90 s (both P = 0.01) in the thrombus group. d-dimer levels were highest at 30 and 90 s for both groups (P = 0.01). PAI-1 and d-dimer levels were strongly correlated at both time points in the thrombus group. Inactivating fibrinolysis due to PAI-1 may lead to asymptomatic VTE after TKA.     

Acetabular Component Positioning in Total Hip Arthroplasty With and Without a Computer-Assisted System: A Prospective,Randomized and Controlled Study

In a study of the acetabular component in total hip arthroplasty, 20 hips were operated on using imageless navigation and 20 hips were operated on using the conventional method. The correct position of the acetabular component was evaluated with computed tomography, measuring the operative anteversion and the operative inclination and determining the cases inside Lewinnek's safe zone. The results were similar in all the analyses: a mean anteversion of 17.4° in the navigated group and 14.5° in the control group (P = .215); a mean inclination of 41.7° and 42.2° (P = .633); a mean deviation from the desired anteversion (15°) of 5.5° and 6.6° (P = .429); a mean deviation from the desired inclination of 3° and 3.2° (P = .783); and location inside the safe zone of 90% and 80% (P = .661). The acetabular component position's tomography analyses were similar whether using the imageless navigation or performing it conventionally.     

Transfer of Hip Arthroplasty Patients Leads to Increased Cost and Resource Utilization in the Receiving Hospital

Factors other than complexity of care often drive the transfer of orthopedic patients to tertiary centers. We sought to compare the demographics, diagnoses, insurance data, peri-operative outcomes and institutional costs of total hip arthroplasty patients transferred from outside facilities with those of patients derived from our clinics. We analyzed 419 consecutive patients as part of a prospective risk study. Transferred patients were older (P = 0.01), less likely to have private insurance (P < 0.0001), and more likely to be admitted on weekends (P = 0.04). Both dislocation and fracture were more prevalent in transferred patients (P = 0.04; P = 0.003). Across all key metrics – including length of stay, mortality scoring, peri-operative complications, and direct and total costs – transferred patients more significantly strained the resources of our arthroplasty center.     

Total Hip Arthroplasty Using Imageless Computer-Assisted Hip Navigation: A Prospective Randomized Study

In a prospective randomized study of two groups of 65 patients each, we compared the acetabular component position when using the imageless navigation system compared to the freehand conventional technique for cementless total hip arthroplasty. The position of the component was determined postoperatively on computed tomographic scans of the pelvis. There was no significant difference for postoperative mean inclination (P = 0.29), but a significant difference for mean postoperative acetabular component anteversion (P = 0.007), for mean deviation of the postoperative anteversion from the target position of 15° (P = 0.02) and for the outliers regarding inclination (P = 0.02) and anteversion (P < 0.05) between the computer-assisted and the freehand-placement group. Our results demonstrate the importance of imageless navigation for the accurate positioning of the acetabular component.     

A Comparison of Surgical Approaches for Primary Hip Arthroplasty: A Cohort Study of Patient Reported Outcome Measures (PROMs) and Early Revision Using Linked National Databases

The posterior and lateral approaches to primary hip arthroplasty were compared using national data from England and Wales. Specific component combinations of the most commonly used cemented and cementless implant brands were analysed separately. There was no significant difference between the approaches for all-cause revision risk (cemented: P = 0.726, cementless: P = 0.295) and revision for dislocation (P = 0.176, P = 0.695) at 12 months following 37,593 procedures, after adjusting for patient and surgical variables. Analysis of 3881 linked episodes found the posterior approach was associated with significantly higher improvement in function (Oxford Hip Score: 20.8 versus 18.9, P < 0.001 (cemented procedures); 21.7 versus 20.2, P = 0.008 (cementless), EQ5D index: 0.416 versus 0.383, P = 0.003; 0.431 versus 0.384, P = 0.003). The posterior approach may offer a functional benefit (albeit small clinically), without increased revision risk.     

The Effect of Payer Type on Clinical Outcomes in Total Knee Arthroplasty

This was a retrospective cohort analysis of 112 patients undergoing primary total knee arthroplasty, wherein baseline demographics, resource utilization, and outcomes were compared by insurance type: Medicaid, Medicare, or private. At the time of surgery, Medicaid patients were younger (P < .0001) and had lower preoperative Knee Society Scores than Medicare and private patients (P = .0125). Medicaid postoperative scores were lower than those of private patients (P = .0223). The magnitude of benefit received by Medicaid patients was similar to Medicare and private patients. Medicaid patients had a higher number of cancelled (P = .01) and missed (P = .0022) appointments relative to Medicare and private patients. Medicaid patients also had shorter average follow-up periods compared to private patients (P = .0003). Access to care and socioeconomic factors may be responsible for these findings.     

Persistent gastrocutaneous fistula: Factors affecting the need for closure

Purpose

The occurrence of gastrocutaneous fistula (GCF) is a well-known complication after gastrostomy tube placement. We explore multiple factors to ascertain their impact on the rate of persistent GCF formation.

Methods

We retrospectively reviewed patient records for all gastrostomies (GT) constructed at our institution from 2007 to 2011. Association of GCF with method of placement, concomitant fundoplication, neurologic findings, duration of therapy, and demographics was evaluated using logistic regression.

Results

Nine hundred fifty patients had GTs placed, of which 148 patients had GTs removed and 47 (32%) of 148 required surgical closure secondary to persistent GCF. Laparoscopic and open procedures comprised 79 (53%) of 148 and 69 (47%) of 148, respectively. Seventeen (22%) patients in the laparoscopic group developed persistent GCF, compared to 30 (43%) in the open group (P = 0.035, OR = 2.52). Seventy-one patients had concomitant Nissen fundoplication. Thirty-one (44%) developed GCF, compared to 16 (21%) without a Nissen (P = 0.002, OR = 4.94). Patients with button in place for 303 days had persistent GCF incidence of 23%, compared to 45% at 540 days (P < 0.001, OR = 3.51) and 50% at 850 days (P = 0.011, OR = 4.51). Patients with device placed at 1.8 months of age were more likely to develop GCF compared to those with device placed at 8.9 months of age (P = 0.017, OR = 2.35).

Conclusion

Open operations, concurrent Nissen and younger age at placement were all statistically significant factors causing persistent GCF.     

Early Death Following Primary Total Hip Arthroplasty

This study aims to describe the timing, cause of death, and excess surgical mortality associated with primary total hip arthroplasty when compared to a population awaiting primary total hip arthroplasty. Mortality rates were calculated at cutoffs of 30 and 90 days post-operation or following the addition to the waiting list. Cause of death was recorded from the death certificate. An excess surgical mortality of 0.256% at 30 days (P = 0.002) and 0.025% at 90 days post-operation (P = 0.892), unaffected by age or gender, was seen with myocardial infarction and pneumonia the cause of death in the majority of cases. By using a more appropriate control population, an excess surgical mortality at 30 days post-operation is demonstrated; the effect diminishes at 90 days post-operation.     

Teriparatide and the risk of nonvertebral fractures in women with postmenopausal osteoporosis

Purpose

In the Fracture Prevention Trial, the risks of any nonvertebral fracture (relative risk [RR] 0.65, P = 0.04) and any fragility nonvertebral fracture (RR 0.47, P = 0.02) were significantly reduced in the teriparatide 20 μg/day (teriparatide) versus placebo group. The purpose of this analysis was to examine the efficacy of teriparatide versus placebo on a variety of other nonvertebral fracture outcomes.

Materials and methods

The Fracture Prevention Trial was a double-blind trial of postmenopausal women with osteoporosis and vertebral fractures randomly assigned to teriparatide (N = 541) or placebo (N = 544) administered by daily self-injection for a median of 19 months and a median follow-up of 21 months. All patients received calcium and vitamin D supplementation. Reports of nonvertebral fractures were collected from patients at each visit and confirmed by review of a radiograph or written radiology report. Nonvertebral fractures were recorded for the following sites: distal radius/wrist, humerus, rib/clavicle, hip, ankle, distal foot, pelvis, or other. Pathological fractures and fractures of the face, skull, metacarpals, fingers and toes were excluded. Fractures were classified by investigators as fragility or traumatic fractures. The three endpoints considered were six nonvertebral sites (nonvert-6), a set of common nonvertebral fractures described in a Food and Drug Administration Guidance document for the treatment and prevention of postmenopausal osteoporosis (FDA), and a European Union major set (major) of nonvertebral fractures.

Results

For teriparatide versus placebo, the point estimates for the RR of nonvert-6 (RR 0.54, P = 0.06; fragility RR 0.32, P = 0.014), FDA (RR 0.60, P = 0.15; fragility RR 0.38, P = 0.05), and major (RR 0.52, P = 0.02; fragility RR 0.38, P = 0.02) nonvertebral fracture endpoints were smaller than for the all nonvertebral fracture endpoint. Lower RRs were observed when the outcomes were limited to fragility fractures, and significant reductions in traumatic nonvertebral fractures were not observed.

Conclusion

In the Fracture Prevention Trial, the risk reduction for nonvertebral fracture in patients treated with teriparatide versus placebo depended on the set of nonvertebral fractures included in the analysis; lower RRs were observed for nonvertebral fractures most likely to be of osteoporotic origin. No significant reductions in traumatic nonvertebral fractures were observed.     

Periprosthetic Joint Infections Treated with Two-Stage Revision over 14 Years: An Evolving Microbiology Profile

Late periprosthetic joint infection (PJI) occurs in 0.3%–1.7% of total hip arthroplasties (THAs) and 0.8%–1.9% of total knee arthroplasties (TKAs). Surgical debridement, explant, and appropriate antibiotics are imperative for successful treatment. We analyzed organisms from PJIs at one institution for temporal trends over 14 years. Poisson regression model demonstrated a linear increase in infection rate for the following bacteria as the primary organism: MRSA (incidence rate ratio [IRR] = 1.11, P = 0.019), Streptococcus viridans (IRR = 1.18, P = 0.002), and Propionibacterium acnes (IRR = 1.21, P = 0.024). The increase in proportion of these organisms may warrant further discussion on pre-surgical MRSA screening and empiric therapy to include MRSA coverage, increased incubation time to detect P. acnes, and dental prophylaxis against S. viridans.     

The Impact of Body Mass Index on Patient Reported Outcome Measures (PROMs) and Complications Following Primary Hip Arthroplasty

Influence of BMI upon patient outcomes and complications following THA was examined across a national cohort of patients. Outcomes were compared by BMI groups (19.0–29.9 kg/m² [reference], 30.0–34.9 kg/m² [obese class I], 35.0 kg/m²+ [obese class II/III]), adjusted for case-mix differences. Obese class I patients had a significantly smaller improvement in OHS (18.9 versus 20.5, P < 0.001) and a greater risk of wound complications (odds ratio [OR] = 1.57, P = 0.006). For obese class II/III patients, there were significantly smaller improvements in OHS and EQ-5D index (P < 0.001), and greater risk of wound complications (P = 0.006), readmission (P = 0.001) and reoperation (P = 0.003). Large improvements in patient outcomes were seen irrespective of BMI, although improvements were marginally smaller and complication rates higher in obese patients.     

National trends in approach and outcomes with appendicitis in children

Background/Purpose

Appendicitis is one of the most common surgical conditions in children. Laparoscopy has become the standard approach to appendectomy over the past decade. Some critics cite a lack of evidence documenting clear advantages to laparoscopy. To define the pattern of approach compared to outcomes in the United States, we analyzed the Pediatric Health Information System (PHIS) database to document the impact on outcomes with the rise in laparoscopy.

Methods

After IRB approval, we queried the PHIS database for all patients over 12 years. The percentages of cases performed open (OA) and laparoscopically (LA) were established for each year. Annual complication percentages were identified for wound infection, intra-abdominal abscess, subsequent laparotomy, and obstruction. For each complication, trend comparisons between LA and OA were made with generalized linear models.

Results

There were 111,194 appendectomies with a positive trend in percentage of laparoscopy from 1999 (22.2%) to 2010 (90.8%), P < 0.0001. Over 12 years, there were significant differential trends between LA and OA in rates of wound infection, abscesses, bowel obstructions, and laparotomies within 30 days (P < 0.0001 for each). There was no trend in wound infection rates within OA over time (P = 0.31), while there was a decrease in infection rates within LA over time (P < 0.0001).

Conclusions

On the basis of a national database analysis, laparoscopy has increased for appendectomy in children over the past 12 years and is associated with a significant decrease in post-operative complications.     

Factors Influencing Revision Risk Following 15 740 Single-Brand Hybrid Hip Arthroplasties : A Cohort Study From a National Joint Registry

This retrospective cohort study of a National Joint Registry data examines survival time to revision following the commonest brand of primary hybrid THA, exploring risk factors independently associated with failure. Overall 5-year revision was 1.56%. In the final adjusted model, revision risk was significantly higher with standard polyethylene (PE) liners (metal-on-PE: hazard ratio [HR] = 2.52, P = 0.005, ceramic-on-PE: HR = 2.99, P = 0.025) when compared to metal-on-highly-cross-linked (XL) PE. Risk of revision with ceramic-on-ceramic bearings was borderline significant (HR = 1.86, P = 0.061). A significant interaction between age and acetabular shell type (solid or multi-hole) was found (P = 0.022), suggesting that solid shells performed significantly better in younger patients. In summary, we found that there were significant differences in implant failure between different bearing surfaces and shell types after adjusting for a range of covariates.     

Staphylococcus aureus bacteremia after thermal injury: The clinical impact of methicillin resistance

Objective

To evaluate the impact of methicillin resistance in Staphylococcus aureus bacteremia (SAB) on mortality and length of stay in burn patients.

Design

Retrospective cohort study.

Setting

A 750-bed tertiary care university hospital in Cologne, Germany.

Patients

Patients registered in the database of the burn intensive care unit (BICU) between 1989 and 2009 with complete data sets (n = 1688).

Results

Over the 21-year study period, 74 patients with SAB were identified; 33 patients had methicillin-resistant S. aureus (MRSA) and 41 methicillin-susceptible S. aureus (MSSA). Comparing the MRSA with the MSSA population the following parameters were significantly different in the univariate analysis: BMI (27.2 kg/m² vs. 23.6 kg/m²; P = 0.05), extent of deep partial thickness burns (17.8% vs. 9.0% of total body surface area; P = 0.007), antibiotic requirement on admission (45.5% vs. 22.0%; P = 0.046), median length of hospitalization prior SAB (24 days vs. 7 days; P < 0.001), packed red blood cells administration (47.6 units vs. 26.1 units; P = 0.003), intubation requirement (100% vs. 80.5%; P = 0.007), intubation period (43.5 days vs. 26.8 days; P = 0.008), catecholamine requirement (90.9% vs. 61.0%; P = 0.004), sepsis (60.6% vs. 34.1%; P = 0.035) and organ failures (81.8% vs. 39.0%; P < 0.001). Regarding outcome parameters, methicillin resistance was not significantly related with mortality (adjusted OR 1.55, 95% CI 0.56–4.28; P = 0.40) and length of BICU stay after SAB (Kaplan–Meier analysis log-rank test P = 0.32; Cox's proportional hazards regression HR 1.22, 95% CI 0.65–2.27, P = 0.535) in the univariate and multivariate analyses.

Conclusion

Our data suggest that methicillin resistance is not associated with significant increases in mortality and length of BICU stay among burn patients with SAB.     

Intestinal ischaemia/reperfusion upregulates β-defensin-2 expression and causes acute lung injury in the rat

Objective

Human β-defensin-2 (BD-2) is a positive ion antimicrobial peptide. We investigated the effects of intestinal ischaemia/reperfusion (II/R) on rat BD-2 mRNA and protein expressions in rat lung to address the potential role of BD-2 in acute lung injury (ALI) induced by II/R.

Methods

Rats were randomly divided into two groups (n = 36 each). (i) Sham control and (ii) II/R group (1 h superior mesenteric artery clamping, followed by reperfusion of different durations). In II/R group, 6 animals were sacrificed at 0 min, 15 min, 30 min, 60 min, 3 h and 6 h after reperfusion, and serum, lung tissue and bronchoalveolar lavage fluid were harvested. Samples were taken at the corresponding time points in the sham group. Lung histological changes were observed under microscope and the pulmonary permeability index (PPI) was calculated. The lung tissue levels of TNFα were detected by ELISA. BD-2 mRNA and protein expressions were examined by RT-PCR and western blotting techniques, respectively.

Results

ALI induced by II/R was confirmed by pathological examination and significantly increased PPI (P < 0.05 or 0.01). II/R significantly increased the lung TNFα levels and upregulated the expressions of BD-2 mRNA and protein expressions (P < 0.05 or 0.01). BD-2 mRNA expression was significantly positively correlated to the lung TNFα level (r = 0.823, P < 0.01) and negatively correlated to PPI (r = −0.615, P < 0.05).

Conclusion

II/R can upregulate BD-2 mRNA and protein expressions in rat lung. BD-2 could be an innate protective factor against II/R-induced lung injury.     

Success of Different Knee Arthrodesis Techniques After Failed Total Knee Arthroplasty: Is There a Preferred Technique?

Arthrodesis is a widely accepted treatment for failed total knee arthroplasty when further revision is contraindicated. In this study, we retrospectively review the pre-operative characteristics, operation techniques, treatment plans, and eventual outcomes in 42 consecutive patients (43 knees) who underwent knee arthrodesis at a single institution. Femorotibial fusion was achieved in 30 cases (75.0%). No cases of implant failure were recorded. Post-operative complications occurred in 20 cases (46.5%). Repeat arthrodesis was performed in 4 cases, and 2 patients eventually required above-the-knee amputation. Comparing the cases with successful vs. unsuccessful outcomes, there was a significant difference in days until hospital discharge following arthrodesis (P = .026), mean erythrocyte sedimentation rate prior to arthrodesis (P = .012), and the proportion of patients with post-operative wound complications (P = .021).     

Laparoscopic versus open appendicectomy in children: A UK District General Hospital experience

Aims

The aim of this study was to evaluate the potential role of laparoscopic appendicectomy in reducing morbidity and length of stay in children compared to open procedures in a UK District General Hospital setting.

Methods

A three-year retrospective review of children ≤ 15 years with histologically confirmed appendicitis who underwent laparoscopic (LA) and/or open (OA) appendicectomy was performed. Choice of operation was based on individual surgeon’s preference and on patient’s body size. Data collected included rate of histologically complicated appendicitis, post-operative length of stay (LOS), and collective and differential morbidity rates, i.e., wound infection, intra-abdominal collection, and ileus. Chi-square and Mann–Whitney tests were used for statistical analysis. P < 0.05 was regarded as significant.

Results

Eighty children (70% male) were identified at median age 11 (3–15) years. They could be divided into complicated (n = 18, 22%) and simple appendicitis (n = 62, 78%). Appendicectomy was performed in all as an OPEN (n = 53, 66%) or LAPAROSCOPIC (n = 27, 34%) procedure. Both groups were comparable in gender distribution (P = 0.11) and rate of complicated appendicitis (30% vs. 19%, respectively; P = 0.27). Median age was significantly lower in the OPEN group [10 (3–15) vs. 12 (7–15) years; P < 0.004]. Laparoscopic appendicectomy had a significantly lower rate of collective morbidity (3.8% vs. 25.9%; P < 0.003), including lower rate of intra-abdominal collection (1.9% vs. 14.8%; P < 0.01). Median LOS was not significantly different (1 day vs. 2 days; P = 0.14).

Conclusion

Laparoscopic appendicectomy in children in a UK District General Hospital is safe and was associated with significantly less post-operative morbidity than the open technique.     

Évaluation des pratiques professionnelles de la prise en charge de la douleur postopératoire à court,moyen et long terme

Objectives

To evaluate the short medium and long-term impact of a quality-improvement program (QIP) in a university hospital using a validated reference tool.

Methods

Seven surgical departments were audited before and after implementation of a QIP in postoperative pain management. Audits were conducted in 2005, 2007, 2009 and 2012. In each audit, 10 medical charts from each surgical department were analyzed for 9 quality criteria. A surgical department score (SDS) was calculated for each department (maximum score = 90). The surgical departments with a SDS < 45 received targeted training sessions.

Results

In 2005, three surgical departments had a SDS < 45. After the first audit, a targeted training sessions was conducted in the three surgical departments, all seven departments improved their scores with a SDS > 45 in 2007. Between 2007 and 2009, all seven departments improved their scores. Conversely, between 2009 and 2012, the SDS diminished in six of the seven surgical departments and four of the nine evaluated quality criteria decreased significantly: right detailed order for postoperative pain analgesia (prescriber identifier, agent used, unit doses, mode of administration; 100% versus 53; P = 0.027), appropriate dosing of steps I and II analgesics (96% versus 80%; P = 0.041), morphine (90% versus 76%; P = 0.039), based on corresponding physician orders and monitor morphine side effects (87% versus 29; P = 0.027).

Conclusion

Audits should be performed regularly (at least every two years) for detecting postoperative pain management degradation. Lack of targeted training sessions can explain partially this degradation.     

The Protective Effect of Pulsed Lavage Against Implant Subsidence and Micromotion for Cemented Tibial Unicompartmental Knee Components: An Experimental Cadaver Study

Cemented UKAs were performed in 12 pairs of human cadaver legs and the bone bed was cleansed using pulsed lavage (group A) and conventional syringe lavage (group B). Subsidence and micromotion of the loaded tibial trays were measured. There was a significant effect of BMD on subsidence (P = 0.043) but not on micromotion. Cement penetration of group A was significantly increased (P = 0.005). Group A showed a reduced implant subsidence (P = 0.025) and micromotion (P = 0.026) compared to group B. The group differences in micromotion and implant subsidence of UKA tibial components were statistically significant but rather small and might clinically be of minor importance. Nevertheless a worse bone quality adversely affected implant subsidence and pulsed lavage had a protective effect in these specimens.