The Fate of Morbidly Obese Patients With Joint Pain: A Retrospective Study of Patient Outcomes.

BACKGROUND: The number of obese patients seeking a total joint arthroplasty (TJA) continues to increase. Weight loss is often recommended to treat joint pain and reduce risks associated with TJA. We sought to determine the effectiveness of an orthopedic surgeon's recommendation to lose weight. METHODS: We identified morbidly obese (body mass index (BMI) 40-49.9 kg/m2) and super obese (BMI ≥50 kg/m2) patients with hip or knee osteoarthritis. Patients with less than 3-month follow-up were excluded. Patient characteristics (age, gender, BMI, comorbidities), disease characteristics (joint affected, radiographic osteoarthritis grading), and treatments were recorded. Clinically meaningful weight loss was defined as weight loss greater than 5%. RESULTS: Two hundred thirty morbid and 50 super obese patients were identified. Super obese patients were more likely to be referred to weight management (52.0% vs 21.7%, P < .001) and were less likely to receive TJA (20.0% vs 41.7%, P = .004). Each 1 kg/m2 increase in BMI decreased the odds of TJA by 10.9% (odds ratio = 0.891, 95% confidence interval: 0.833-0.953, P = .001). Forty (23.0%) of the nonoperatively treated patients achieved clinically meaningful weight loss, and 19 (17.9%) patients who underwent TJA lost weight before surgery. After surgery, the number of patients who achieved a clinically meaningful weight loss grew to 32 (30.2%). CONCLUSION: In morbid and super obese patients, increasing BMI reduces the likelihood that a patient will receive TJA, and when counseled by their orthopedic surgeon, few patients participate in weight-loss programs or are otherwise able to lose weight. Weight loss is an inconsistently modifiable risk factor for joint replacement surgery.

Preoperative Smoking Cessation as a Durable Form of Long-Term Smoking Cessation.

Smokers who undergo total joint arthroplasty (TJA) face increased rates of medical and surgical complications that can be reduced by preoperative smoking cessation. We investigated the long-term durability of preoperative smoking cessation among TJA patients. Twenty-seven TJA patients who were identified as having an active history of smoking at the preoperative appointment before TJA consented to telephone survey about their perioperative and current smoking status. Average time from operation to survey was 3.7 years. Of the 27 patients, 21 (77.8%) were identified as having quit smoking prior to surgery. Of these 21 patients, 10 (47.6%) self-reported continued abstinence from smoking at the time of survey. Our cessation rate was significantly lower than reported long-term smoking cessation rates with standard therapies (p < 0.001). Our results suggest that preoperative counseling and a requirement for smoking-cessation prior to elective TJA may have long-term durability that exceeds that of popular reported methods. (Journal of Surgical Orthopaedic Advances 29(2):103-105, 2020).

Risk Factors for Fungal Prosthetic Joint Infection.

Background: Fungal prosthetic joint infections (PJIs) are rare and often associated with poor outcome; however, risk factors are not well described. Methods: This was a retrospective case control study among all patients with PJIs from 2006-2016 at two major academic centers. Each fungal PJI case was matched 1:1 with a bacterial PJI control by joint (hip, knee, shoulder) and year of diagnosis. We compared demographics, comorbidities, and clinical characteristics between cases and controls using chi square/Fisher's exact or Wilcoxon rank sum test. Independent risk factors were identified with multivariable logistic regression. Results: Forty-one fungal PJIs occurred over the study and 61% were due to Candida albicans. The hip was involved in 51.2% of cases, followed by the knee (46.3%). Compared to bacterial PJI, fungal PJI cases were more likely to have received antibiotics within the previous 3 months (70.7% vs 34%, P=.001), wound drainage lasting >5 days (48% vs 9%, P=.0002), had a lower median CRP (2.95 mg/dl vs 5.99, P=.013) and synovial fluid white blood cell count (13,953 cells/mm3 vs 33,198, P=.007), and a higher proportion of prior two-stage exchanges (82.9% vs 53.6%, P=.008). After controlling for center, prolonged wound drainage (OR, 7.3; 95% CI, 2.02-26.95) and recent antibiotics (OR, 3.4; 95% CI, 1.2-9.3) were significantly associated with fungal PJI. Conclusion: In our study, Candida albicans was the most common species in fungal PJIs and prolonged wound drainage and recent antibiotics were independent risk factors. These clinical characteristics may help providers anticipate fungal PJI and adjust management strategies.

Optimal Length of Stay Following Total Joint Arthroplasty to Reduce Readmission Rates.

BACKGROUND: Length of stay (LOS) following total joint arthroplasty (TJA) continues to decrease. The effects of this trend on readmission risk and total cost are unclear. We hypothesize that optimal LOS following TJA minimizes index hospitalization, early readmission risk, and total cost. METHODS: Retrospective data from the South Carolina Department of Revenue and Fiscal Affairs was reviewed for patients who underwent primary TJA in South Carolina from 2000 to 2015 (n = 172,760). Data for readmissions within 90 days were included. Severity of illness was estimated by Elixhauser score (EH). Index LOS is defined as the surgery and the subsequent hospital stay. RESULTS: Patients with more significant medical comorbidities (EH ≥ 4) had significantly longer LOS than healthier patients (4.0 vs 3.4 days, P < .001). Independent of EH, readmitted patients had a significantly longer index LOS than those never readmitted (4.3 vs 3.6 days, P < .001). For healthier patients (EH ≤ 3), each additional inpatient day increased readmission risk, while among sicker patients, staying 2 days vs 1 day was protective against readmission risk. Since 2000, the total index cost of TJA has doubled and average cost per inpatient day has tripled, but readmission rates remain essentially unchanged (7.4% to 7.0%). CONCLUSION: Increased LOS was associated with increased readmission risk. Patients with greater medical comorbidities stay longer to protect against readmission. Optimal LOS after TJA is highly influenced by the patient's overall health. Despite a 300% increase in TJA daily cost, readmission rate has changed minimally over the last 15 years.

Surgical Complications Associated With Atypical Femur Fractures Attributed to Bisphosphonate Use.

Complications of atypical femur fractures (AFFs) are common. AFFs often receive the same treatment as other femoral fractures; however, there appears to be a higher rate of adverse outcomes. Nine patients sustained a total of 13 AFFs, had documented bisphosphonate use before fracture, and had surgery between 2006 and 2012. Complications included continued pain, surgical revision, nonunion, malunion, deformity, or heterotopic ossification. The overall complication rate was 33.3%, with four of the 12 surgeries performed at this institution resulting in one nonunion and three minor complications. None of the primary fixations required revision. There was a higher complication rate for AFFs when compared with non-bisphosphonate-related intramedullary nail femur fracture fixations. This cohort demonstrated a lower rate of major complications compared to the literature. Using a reamed, statically locked nail, halting bisphosphonate medication, and allowing early weight bearing is a safe and efficacious method to treat atypical femur fractures. (Journal of Surgical Orthopaedic Advances 27(1):14-20, 2018).

Prefrontal versus motor cortex transcranial direct current stimulation (tDCS) effects on post-surgical opioid use.

BACKGROUND: Pain is often a complaint that precedes total knee arthroplasty (TKA), however the procedure itself is associated with considerable post-operative pain lasting days to weeks which can predict longer-term surgical outcomes. Previously, we reported significant opioid-sparing effects of motor cortex transcranial direct current stimulation from a single-blind trial. In the present study, we used double-blind methodology to compare motor cortex tDCS and prefrontal cortex tDCS to both sham and active-control (active electrodes over non-pain modulating brain areas) tDCS. METHODS: 58 patients undergoing unilateral TKA were randomly assigned to receive 4 20-min sessions (a total of 80 min) of tDCS (2 mA) post-surgery with electrodes placed to create 4 groups: 1) MOTOR (n = 14); anode-motor/cathode-right prefrontal, 2) PREFRONTAL (n = 16); anode-left-prefrontal/cathode-right-sensory, 3) ACTIVE-CONTROL (n = 15); anode-left-temporal-occipital junction/cathode-medial-anterior-premotor-area, and 4) SHAM (n = 13); 0 mA-current stimulation using placements 1 or 2. Patient controlled analgesia (PCA; hydromorphone) use was tracked during the ∼72-h post-surgery. RESULTS: Patients in the sham group and the active-control group used 15.4 mg (SD = 14.1) and 16.0 mg (SD = 9.7) of PCA hydromorphone respectively. There was no difference between the slopes of the cumulative PCA usage curves between these two groups (p = 0.25; ns). Patients in the prefrontal tDCS group used an average of 11.7 mg (SD = 5.0) of PCA hydromporhone, and the slope of the cumulative PCA usage curve was significantly lower than sham (p < 0.0001). However, patients in the motor tDCS group used an average of 19.6 mg (SD = 11.9) hydromorphone and the slope of the PCA use curve was significantly higher than sham (p < 0.0001). CONCLUSIONS: Results from this double-blind cortical-target-optimization study suggest that anodal transcranial direct current stimulation (tDCS) over the left prefrontal cortex may be a reasonable approach to reducing post-TKA opioid requirements. Given the unexpected finding that motor cortex failed to produce an opioid sparing effect in this follow-up trial, further research in the area of post-operative cortical stimulation is still needed.

Fewer Complications Following Revision Hip and Knee Arthroplasty in Patients With Normal Vitamin D Levels.

BACKGROUND: Surgeons and hospitals increasingly face penalty for complications and readmission following total joint arthroplasty; therefore, optimization of modifiable risk factors is paramount. Literature associates low vitamin D with risk of periprosthetic joint infection, and we hypothesized low vitamin D to be predictive of increased rate of complications and readmissions. METHODS: A retrospective review of 126 revision total joint arthroplasty patients between 2010 and 2014 was performed. RESULTS: Low vitamin D was not associated with risk of 30-day readmission but was found to be associated with an increased risk of 90-day complications as well as periprosthetic joint infection as the reason for revision surgery. CONCLUSION: Preoperative vitamin D level should be considered a modifiable risk factor for complications following revision arthroplasty.

Process Improvement Project Using Tranexamic Acid Is Cost-Effective in Reducing Blood Loss and Transfusions After Total Hip and Total Knee Arthroplasty.

BACKGROUND: Tranexamic acid (TXA) has been associated with decreased blood loss and transfusion after total hip arthroplasty (THA) and total knee arthroplasty (TKA). The purpose of this study was to examine both transfusion utilization and the economic impact of a Process Improvement Project implementing TXA for THA and TKA. METHODS: After standardization of TXA administration in THA and TKA patients, retrospective data were compared from 12 consecutive months before (group A, n = 336 procedures) and after (group B, n = 436 procedures) project initiation. RESULTS: TXA administration increased with project implementation (group A = 3.57%, group B = 86.01%) and was associated with reductions in perioperative hemoglobin decrement (20.2%), patients transfused (45%), and number of units transfused per patient (61.9%). Cost savings were notable per patient ($128) and annually program wide ($55,884) with the primary THA subgroup contributing the most to the savings. No increase in adverse effects was observed. CONCLUSION: Standardized administration of TXA is an effective and economically favorable blood-reduction strategy for patients undergoing elective THA or TKA. Although reduction in transfusions with TXA may be greater after TKA, the economic and clinical impact of transfusion reduction is more substantial in THA patients.

Comparison of Lumbar Epidurals and Lumbar Plexus Nerve Blocks for Analgesia Following Primary Total Hip Arthroplasty: A Retrospective Analysis.

BACKGROUND: Total hip arthroplasty (THA) is associated with significant postoperative pain. Both lumbar epidurals and lumbar plexus nerve blocks have been described for postoperative pain control, but it is unclear if one technique is more beneficial. METHODS: Using electronic medical records, a randomly selected, cohort of 58 patients with lumbar epidurals were compared with 58 patients with lumbar plexus nerve blocks following primary THA. The primary end point was 48-hour postoperative opiate consumption. Secondary end points included time of first ambulation, distance ambulated, level of assistance with ambulation, presence of side effects, and time to discharge. Descriptive statistics were calculated to characterize subjects in the different block-type groups. Comparisons in morphine consumption were conducted using linear mixed models. Primary and secondary end points were examined in multivariable models. RESULTS: Patients with lumbar plexus blocks consumed less opiates at 24, 36, and 48 hours relative to patients that received lumbar epidural catheters (P = .047, .002, and .002, respectively). Patients with lumbar plexus blocks ambulated earlier (24.6 ± 2.01 hours vs 31.7 ± 3.01 hours) and farther relative to patients with epidurals (P < .001 for both) and had discharge orders written earlier (58.2 ± 6.68 hours vs 73.6 ± 6.35 hours). CONCLUSION: In comparison to lumbar epidural catheters, lumbar plexus nerve blocks are an effective pathway for postoperative pain control following primary THA. Furthermore, this clinical pathway expedites physical rehabilitation and is more compatible with postoperative prophylactic anticoagulants.

Complications of hip and knee joint replacement in solid-organ transplant patients.

This study investigated complication rates for 68 solid-organ transplant patients who had undergone 94 primary hip or knee joint replacements at a single institution from 1995 to 2008. There was a deep infection rate of 6.8% in the transplant patients compared to a 1.9% deep infection rate for all primary joint replacement patients at the Medical University of South Carolina over the same time period (odds ratio 4.48). All four infections in the transplant group occurred in diabetic patients. The joint revision rate for transplant patients was 13% (deep infection 6.8%, aseptic loosening 5.1%, instability 1.7%). Other complications included superficial infections (5.1%), deep venous thromboses (3.4%), and a nonfatal pulmonary embolus (1.7%). The deep infection rate for joint replacement in solid-organ transplant patients was higher than rates reported by most similar studies, and diabetic patients may be at particular risk.

The efficacy of automated intermittent boluses for continuous femoral nerve block: a prospective, randomized comparison to continuous infusions.

STUDY OBJECTIVE: To determine whether an automated intermittent bolus technique provides enhanced analgesia compared with a continuous infusion for femoral nerve block. DESIGN: Prospective, single-blinded, randomized controlled trial (ClinicalTrials.gov Identifier: NCT01226927). SETTING: Perioperative areas and orthopedic surgical ward of a university hospital. PATIENTS: 45 ASA physical status 1, 2, and 3 patients undergoing unilateral primary total knee arthroplasty. INTERVENTIONS: All patients received single-injection sciatic and femoral nerve blocks plus femoral nerve catheter placement for postoperative analgesia. Patients were randomly assigned to an automated intermittent bolus (5 mL every 30 min with 0.1 mL/hr basal rate) or a continuous infusion (10.1 mL/hr) delivery method of 0.2% ropivacaine. MEASUREMENTS: Consumption of intravenous patient-controlled analgesia (IV-PCA) and visual analog scale (VAS) pain scores were assessed postoperatively at set intervals until the morning of postoperative day (POD) 2. MAIN RESULTS: The mean (SEM) cumulative IV-PCA dose (mg of hydromorphone) for the 36-hour postoperative interval measured was 12.9 ± 2.32 in the continuous infusion rate group (n = 20) and 7.8 ± 1.02 in the intermittent bolus group [n = 21, t(39) = 2.04, P = 0.048; a 39 ± 14% difference in total usage]. Pain scores were statistically significantly lower in the intermittent bolus group in the afternoon of POD 1 (t(39) = 2.47, P = 0.018), but were otherwise similar. CONCLUSIONS: An automated intermittent bolus infusion technique for femoral nerve catheters is associated with clinically and statistically significantly less IV-PCA use (ie, an opioid-sparing effect) than a continuous infusion technique.

Transcranial direct current stimulation (tDCS) reduces postsurgical opioid consumption in total knee arthroplasty (TKA).

BACKGROUND: Although pain is often a symptom that precedes total knee arthroplasty (TKA), the procedure itself is associated with considerable postoperative pain lasting days to weeks. Postoperative pain control is an important factor in determining recovery time, hospital length of stay, and rehabilitation success. Several brain stimulation technologies including transcranial direct current stimulation (tDCS) have demonstrated promise as treatments for a variety of pain conditions. The present study examined the effects of 4 sessions of tDCS on post-TKA pain and opioid consumption. MATERIALS AND METHODS: Forty patients undergoing unilateral TKA were randomly assigned to receive a total of 80 minutes of real (n=20) or sham tDCS (n=20) with the anode over the knee representation of the motor strip (C1h or C2h corresponding to the target knee) and cathode over the right dorsolateral prefrontal cortex (F3; located by the EEG 10-20 System). Patient-controlled analgesia ( hydromorphone) use was tracked during the ∼48 hours postsurgery. RESULTS: Patients in the real tDCS group used an average of 6.6 mg (SD=5.3) of patient-controlled analgesia hydromorphone, whereas those in the sham group used 12.3 mg (SD=6.6; t37=2.93, P=0.006). Despite using less opioid medication, participants in the real tDCS group reported no pain exacerbation or worse mood with respect to those in the sham tDCS group. CONCLUSIONS: Results from this pilot feasibility study suggest that tDCS may be able to reduce post-TKA opioid requirements. Although these results are preliminary, the data support further research in the area of adjunctive cortical stimulation in the management of postsurgical pain.

A biomechanical comparison of periprosthetic femoral fracture fixation in normal and osteoporotic cadaveric bone.

Several techniques are described for fixation of Vancouver B1 femoral shaft fractures after total hip arthroplasty. Twenty-four femurs were scanned by dual x-ray absorptiometry scanned and matched for bone mineral density. Femurs were implanted with a cemented simulated total hip prosthesis with a simulated periprosthetic femur fracture distal to the stem. Fractures were fixed with Synthes (Paoli, Pa) 12-hole curved plates and 4 different constructs proximally. Each construct was loaded to failure in axial compression. Constructs with locking and nonlocking screws demonstrated equivalent loads at failure and were superior in load at failure compared with cables. Cable constructs failed proximally. No proximal failures occurred in specimens fixed with screws and cables. A combination of locked or nonlocked screws and supplemental cable fixation is recommended for the treatment of Vancouver B1 periprosthetic femur fractures.

Platelet-rich and platelet-poor plasma: development of an animal model to evaluate hemostatic efficacy.

Hemostasis is important for any surgical procedure. One method uses autologous platelet-rich and/or platelet-poor plasma sprayed on the wound site. Although effective, there are little quantitative data available to fully document the extent to which these autologous products function as hemostats. Also, limitations in current animal models make quantitative study of topical hemostats difficult. A porcine partial-thickness skin wound model was developed to compare the hemostatic ability of these treatments with untreated control wounds. Rectangular partial-thickness dermal wounds were created in the back of a pig, which was then sprayed with activated platelet-rich plasma, activated platelet-poor plasma, or left untreated. Bleeding was quantified by two methods: 1) gravimetric measurement of exudate transfer to a sponge over a 15-minute interval, and 2) iron assay of the exudate over this same interval. Values for treated wounds were normalized to those of control wounds to minimize interanimal variability. Both gravimetric and iron assay measurements demonstrated that platelet-rich plasma was effective within 5 minutes after application with normalized bleeding values of approximately 35% and 20%, respectively, of the untreated controls. Corresponding values for platelet-poor plasma were approximately 90% and 65%, respectively, with differences only significant for the iron assay method measured on 10- and 15-minute wound exudate. Although both platelet-rich and platelet-poor plasma demonstrated hemostatic potential, the effect was more robust with the former. Iron assay was a more accurate method of measuring bleeding than gravimetric analysis.