Minimizing Opioids After Joint Operation: Protocol to Decrease Postoperative Opioid Use After Primary Total Knee Arthroplasty.

Background: For decades, opioids have been the mainstay in pain management after total joint arthroplasty despite evidence that their use should be curtailed. To limit unnecessary prescribing of opioids, the US Department of Veterans Affairs (VA) Portland Health Care System Total Joints Service implemented the Minimizing Opioids After Joint Operation (MOJO) postoperative pain protocol in 2018 to reduce opioid use following total knee arthroplasty (TKA). This protocol included reductions of inpatient and outpatient opioid prescribing, preoperative optimization, use of perioperative nerve blocks, and surgery without a tourniquet.

Axial load weightbearing radiography in determining lateral malleolus fracture stability: a cadaveric study.

Background: Ankle fractures are the most common fracture treated by orthopaedic surgeons in the United States. Isolated lateral malleolus fractures are treated nonoperatively, while associated deltoid disruption injuries are unstable and usually treated by fixation of the fracture. Various stress radiographs and MRI have been used to determine deltoid competency and the subsequent need for operative stabilization of lateral malleolus fractures.

Subcutaneous methylnaltrexone for treatment of acute opioid-induced constipation: phase 2 study in rehabilitation after orthopedic surgery.

Background: Methylnaltrexone has been shown to be effective for treating opioid-induced constipation (OIC) in chronic settings, but its effects on acute OIC have not been studied.

Objective: To assess safety and efficacy of subcutaneous methylnaltrexone in patients with acute OIC after orthopedic procedures.

Design: Double-blind, randomized, parallel-group, placebo-controlled, hypothesis-generating phase 2 study.

New technique for humerus shaft fracture retrograde intramedullary nailing.

Humeral shaft fracture intramedullary nailing is less invasive than plates and screws. Antegrade technique has postoperative shoulder pain, increased rehab time, and frequent reoperation for rod removal. Published retrograde technique is not collinear with the shaft, has insertion site fractures (5% to 15%), and radial nerve palsies (5%).

A quantitative analysis of tension band plating of the femur diaphysis.

Objectives: To measure quantitatively the strains in the concave and convex sides of a femur to substantiate the Arbeitsgemeinschaft für Osteosynthesefragen (AO) tension band principle.

Methods: Eight cadaveric fresh-frozen femurs were cleaned of soft tissue and prepared for mounting the strain gages (Vishay, Raleigh, NC). The student strain gages were mounted at the anterior, lateral and medial surfaces of a femur.

Biomechanics of humerus fracture fixation by locking, cortical, and hybrid plating systems in a cadaver model.

The goal of this study was to discover how locking or cortical screws or a hybrid of both would perform in stabilizing a simulated humerus fracture. We simulated stripping of screw threads or poor bone quality by overdrilling the screw hole, and also studied a control group with no overdrilling. A total of 38 fresh frozen cadaver humeri were divided into 2 groups: 16 undergoing overdrilling with a drill bit 0.

Primary cortical brain cells influence osteoblast activity.

The presence of neuropeptides and neuroreceptors in the bone have been reported in several studies. Bone turn-over seems to be controlled by the nervous system. The actual pathway or the control mechanism is still under investigation.

Elevated serum concentrations of cobalt, chromium, nickel, and manganese after metal-on-metal alloarthroplasty of the hip: a prospective randomized study.

In this prospective randomized study, we investigate metal ion concentrations and clinical outcome 2 years after metal-on-metal (28 patients) or metal-on-polyethylene (26 patients) hip arthroplasty with 28-mm modular heads. Metal ion concentrations in patient serum were analyzed by high-resolution plasma mass spectrometry. The clinical outcome was almost identical in both groups with respect to the Harris hip score and the Medical Outcome Study Short Form-36; and on plain radiography, no signs of loosening occurred in any group.

A new biodegradable polyester elastomer for cartilage tissue engineering.

The objective of this study is to assess whether a new biodegradable elastomer, poly(1,8-octanediol citrate) (POC), would be a suitable material to engineer elastomeric scaffolds for cartilage tissue engineering. Porous POC scaffolds were prepared via the salt-leaching method and initially assessed for their ability to rapidly recover from compressive deformation (% recovery ratio). Controls consisted of scaffolds made from other materials commonly used in cartilage tissue engineering, including 2% agarose, 4% alginate, non woven poly(glycolic acid) (PGA) meshes, and non woven poly(L-lactide-co-glycolide) (PLGA) meshes.

Low IGF-I in synovial fluid and serum in patients with aseptic prosthesis loosening.

Background: We have previously shown that proliferation in primary cultures of human osteoblast-like cells is lower after exposure to synovial fluid from patients with aseptic prosthesis loosening than after exposure to synovial fluid from patients with osteoarthrosis.

Materials And Methods: Insulin-like growth factors (IGF) I and II and IGF binding proteins (IGFBP) 3-6, were measured with radioimmunoassy in synovial fluid and in serum from patients with aseptic prosthesis loosening or osteoarthrosis. Proliferation in osteoblast-like MG-63 cells was studied with the CyQUANT assay.

Cobalt ions influence proliferation and function of human osteoblast-like cells.

Cobalt is the major component in many orthopedic implants and the introduction of a second generation of metal on metal bearing prosthesis systems actualizes the toxicity and biocompatibility of this compound. We studied the effect of cobalt ions on primary cultures of human osteoblast-like cells. Cobalt ions dissolved in cell culture medium caused a dose-dependent decrease in proliferation of human osteoblasts measured as (3H)thymidine incorporation.