Standardized total knee arthroplasty pathway improves outcomes in minority patients.

OBJECTIVES: Inferior total knee arthroplasty (TKA) outcomes are reported in minority populations. Standardized TKA pathways improve outcomes but have not been studied extensively in minority populations. This study evaluated the impact of TKA pathway standardization at an urban teaching hospital that predominantly treats minority patients. STUDY DESIGN: Retrospective cohort study. METHODS: This study compared primary TKA outcomes before and after implementation of a standardized multidisciplinary pathway that emphasized preoperative education and discharge planning, preemptive multimodal pain control, and early rehabilitation. Patients were grouped as "nonpathway" (n = 144) or "pathway" (n = 182) based on whether they underwent TKA before or after pathway implementation. Outcomes included length of stay (LOS), patient-controlled analgesia (PCA) use, blood transfusion, postoperative hemoglobin, complications, and discharge disposition. Analysis involved negative binomial and multiple logistic regression models, t tests, and Fisher's exact tests. RESULTS: Mean (SD) age was 61.6 (8.7) years, and 36.5% were men. Ethnicity of the patients included Hispanic (44.5%), African American (27.9%), Asian (14.1%), and White (12.9%). Pathway and nonpathway patients were similar demographically and racially. Pathway patients had shorter LOS (P = .04), less PCA use (P < .001), more frequent discharge home (P = .03), fewer transfusions (P = .002), and higher postoperative hemoglobin (P < .001). Overall incidence of complications was similar (P = .61). Nonpathway patients developed more cardiopulmonary complications (P = .02), whereas pathway patients had more wound dehiscence (P = .01). CONCLUSIONS: Compared with nonpathway patients, standardized TKA pathway patients had shorter LOS, decreased PCA use, increased discharge to home, fewer blood transfusions, and higher postoperative hemoglobin, with no difference in total incidence of complication.

Ultrasound-guided suprainguinal fascia iliaca compartment block versus periarticular infiltration for pain management after total hip arthroplasty: a randomized controlled trial.

BACKGROUND AND OBJECTIVES: Fascia iliaca compartment block (FICB) has been shown to provide excellent pain relief in patients undergoing total hip arthroplasty (THA). However, the analgesic efficacy of FICB, in comparison with periarticular infiltration (PAI) for THA, has not been evaluated. This randomized, controlled, observer-blinded study was designed to compare suprainguinal FICB (SFICB) with PAI in patients undergoing THA via posterior approach. METHODS: After institutional review board approval, 60 consenting patients scheduled for elective THA were randomized to one of two groups: ultrasound-guided SFICB block or PAI. The local anesthetic solution for both the groups included 60 mL ropivacaine 300 mg and epinephrine 150 µg. The remaining aspects of perioperative care, including general anesthetic and non-opioid multimodal analgesic techniques, were standardized. An investigator blinded to group allocation documented pain scores at rest and with movement and supplemental opioid requirements at various time points. Patients were evaluated for sensory changes and quadriceps weakness in the operated extremity. RESULTS: There were no differences between the groups with respect to demographics, intraoperative opioid use, duration of surgery, recovery room stay, nausea scores, need for rescue antiemetics, time to ambulation and time to discharge readiness as well as 48 hours postoperative opioid requirements. The pain scores at rest and with movement also were similar at all time points. Significantly more patients in the SFICB group experienced muscle weakness at 6 hours after surgery. CONCLUSIONS: Under the circumstances of our study, in patients undergoing THA, SFICB provided the similar pain relief compared with PAI, but was associated with muscle weakness at 6 hours postoperatively. TRIAL REGISTRATION NUMBER: NCT02658240.

Are patients being evaluated for periprosthetic joint infection prior to referral to a tertiary care center?

BACKGROUND: Patients with a painful or failed total joint arthroplasties should be evaluated for periprosthetic joint infection (PJI). The purpose of this study is to determine if patients referred to a tertiary care center had been evaluated for PJI according to the American Academy of Orthopaedic Surgeons (AAOS) clinical practice guidelines. METHODS: One hundred thirteen patients with painful hip (43) or knee (70) arthroplasties were referred to a single provider by orthopaedic surgeons outside our practice between 2012 and 2014. We retrospectively evaluated the workup by referring physicians, including measurement of serum erythrocyte sedimentation rate and C-reactive protein, performance of a joint aspiration if these values were abnormal, and obtainment of synovial fluid white blood cell count, differential, and cultures. RESULTS: Sixty-two of 113 patients (55%) did not have a workup that followed AAOS guidelines. Serum erythrocyte sedimentation rate and C-reactive protein were ordered for 64 of the 113 patients (57%). Of 25 patients with elevated inflammatory markers warranting aspiration, 15 (60%) had an aspiration attempted, with synovial fluid white blood cell, differential, and cultures obtained in 9 of 12 (75%) aspirations that yielded fluid. Of the 62 patients with an incomplete infection workup, 11 (18%) had a bone scan, 6 (10%) a computed tomography scan, and 3 (5%) a magnetic resonance imaging. Twelve of the 113 patients (11%) were ultimately diagnosed with PJI, with 5 undiagnosed prior to referral. CONCLUSIONS: The AAOS guidelines to evaluate for PJI are frequently not being followed. Improving awareness of these guidelines may avoid unnecessary and costly evaluations and delay in the diagnosis of PJI.

Three-dimensional printing for preoperative planning of total hip arthroplasty revision: case report.

Three dimensional (3D) printing can be used to create material models to aid preoperative planning of complex orthopedic procedures as exemplified by this case of total hip arthroplasty failure due to infection with resulting severe acetabular bone stock deficiency. The 3D model allowed for trialing of the acetabular component to determine cup size, position, and screw placement. Most importantly, the model confirmed that there was not a pelvic discontinuity and the revision shell would be sufficient for the reconstruction. Previously, the cost and complexity of utilization of 3D printers were prohibitive. Recent improvements in commercially available 3D printers have made rapid prototype model creation a realistic option, which can facilitate difficult surgery.

Taper Failure After Large-Diameter Metal-on-Metal Total Hip Arthroplasty.

The use of metal-on-metal bearing surfaces for total hip arthroplasty increased dramatically in the past decade for a variety of reasons, including the advantage of using larger-diameter femoral heads to reduce instability. However, recent research suggesting negative outcomes and high failure rates associated with some of these implants has decreased their use. Further, the use of larger-diameter femoral heads on relatively small femoral neck tapers has caused concern about localized corrosion at this junction, particularly with varus femoral alignment and longer femoral neck and head lengths. Although the advent of modular components offers the surgeon greater intraoperative flexibility, this modularity may prove to be a weak link when coupled with large-diameter femoral heads. This report describes a patient with a history of bilateral metal-on-metal total hip arthroplasty complicated by failure of the right hip as a result of fretting and mechanically assisted crevice corrosion. Notching of the femoral neck and head dissociation occurred 10 years after the primary procedure. The authors describe the patient's presenting symptoms, the possible etiology of the catastrophic failure, and the method of treatment and provide a brief review of metal-on-metal implants that may shed some light on the complications in this case. [Orthopedics.2016; 39(5):e984-e987.].

Lrp5-independent activation of Wnt signaling by lithium chloride increases bone formation and bone mass in mice.

One of the well characterized cell biologic actions of lithium is the inhibition of glycogen synthase kinase-3beta and the consequent activation of canonical Wnt signaling. Because deficient Wnt signaling has been implicated in disorders of reduced bone mass, we tested whether lithium could improve bone mass in mice. We gavage-fed lithium chloride to 8-week-old mice from three different strains (Lrp5(-/-), SAMP6, and C57BL/6) and assessed the effect on bone metabolism after 4 weeks of therapy. Lrp5(-/-) mice lack the Wnt coreceptor low-density lipoprotein receptor-related protein 5 and have markedly reduced bone mass. Lithium, which is predicted to act downstream of this receptor, restored bone metabolism and bone mass to near wild-type levels in these mice. SAMP6 mice have accelerated osteoporosis due to inadequate osteoblast renewal. Lithium significantly improved bone mass in these mice and in wild-type C57BL/6 mice. We found that lithium activated canonical Wnt signaling in cultured calvarial osteoblasts from Lrp5(-/-) mice ex vivo and that lithium-treated mice had increased expression of Wnt-responsive genes in their bone marrow cells in vivo. These data lead us to conclude that lithium enhances bone formation and improves bone mass in mice and that it may do so via activation of the canonical Wnt pathway. Lithium has been used safely and effectively for over half a century in the treatment of bipolar illness. Prospective studies in patients receiving lithium should determine whether it also improves bone mass in humans.