Proximal tibial replacement with megaprosthesis in the setting of proximal tibial nonunion: A case report.

Background: Fracture nonunion is a major concern among an orthopaedic patient population, especially in those who have sustained traumatic fractures involving the tibia. Strong risk factors for nonunion include age, smoking history, and a poor diet. The incidence of nonunion also increases with each additional failed surgical intervention.

The Surgical Outcomes of Pedicle Subtraction Osteotomy per Different First Assistant: Retrospective Analysis of 312 Cases.

Introduction: Pedicle subtraction osteotomies (PSOs) are complex spinal deformity surgeries that are associated with high complication rates. They are typically done by an experienced spine surgeon with another attending, resident, or physician assistant serving as the first assistant. The purpose of this study was to determine whether selecting a surgical team for single-level PSO based on case difficulty and fusion length could equalize intraoperative and perioperative outcomes among three groups: dual-attending (DA), attending and orthopaedic resident (RS), and attending and physician assistant (PA).

Superficial Femoral Artery Pseudoaneurysm After Intra-articular Adductor Canal Pain Catheter Placement for Total Knee Arthroplasty.

Vascular injury following total knee arthroplasty (TKA) is a rare complication. The authors present a case of superficial femoral artery aneurysm in a 60-year-old man following elective TKA in the setting of intra-articular On-Q* (Avanos Medical) pain catheter placement into the adductor canal for postoperative pain control. This is the second reported case of pseudoaneurysm secondary to adductor canal block.

Expansion of myeloid-derived suppressor cells contributes to metabolic osteoarthritis through subchondral bone remodeling.

Background: Osteoarthritis (OA) subsequent to acute joint injury accounts for a significant proportion of all arthropathies. Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of myeloid progenitor cells classically known for potent immune-suppressive activity; however, MDSCs can also differentiate into osteoclasts. In addition, this population is known to be expanded during metabolic disease.

Low Incidence of Postoperative Complications With Navigated Total Knee Arthroplasty.

Background: A number of postoperative complications of navigated total knee arthroplasty (TKA) have been discussed in the literature, including tracker pin site infection and fracture. In this article, we discuss the low postoperative complication rate in a series of 3100 navigated TKAs and the overall complication rate in a systematic analysis of the literature.

Methods: Three thousand one hundred consecutive patients with navigated TKAs from 2001-2016 were retrospectively evaluated for complications specific to navigation.

Short Term Outcomes of a Hydroxyapatite Coated Metal Backed Patella.

We retrospectively evaluated the records and radiographs of 101 knees with a hydroxyapatite coated metal backed patella (HAP) and 50 knees with a cemented polyethylene patella (CP) with minimum two year clinical follow up. There were no patellar revisions during the study period. Patients in both the HAP and CP groups had similar clinical outcomes at final follow-up.

Torsion deformity and joint loading for medial knee osteoarthritis.

Purpose: The consequences of lower limb torsion deformity on knee loading in knee osteoarthritis are poorly understood. The purpose of this study was to quantify the associations between the mechanical axis, tibial torsion and knee loading in subjects with medial knee OA and in controls.

Methods: Twenty-four subjects: end-staged medial knee osteoarthritis (OA) with apparent torsion deformity (TKO, n=6) and without torsion deformity (KOA, n=8) and controls (CON, n=10) were imaged using long standing lower extremity (LSLE) radiographs and computed tomography (CT).

Passive knee kinematics before and after total knee arthroplasty: are we correcting pathologic motion?

The change in coronal plane deformity throughout a range of flexion before and after total knee arthroplasty (TKA) has not been reported. Unlike most alignment assessments traditionally reporting coronal plane alignment in a standing position under static conditions, this study reports deformity throughout the flexion arc before and after deformity correction. One hundred fifty-two TKA patients using the anteroposterior axis for femoral component rotation and computer navigation techniques were included in the study.

Reliability of measuring long-standing lower extremity radiographs.

The mechanical axis of the lower extremity was measured using preoperative long-standing radiographs in 56 patients undergoing total knee arthroplasty with the Stryker Navigation System (Stryker, Kalamazoo, Mich). Each radiograph was measured by four physicians, three times, in random order, and at delayed intervals. Measurements from each physician produced intraclass correlation coefficients of 0.

Effect of one- and two-pin reference anchoring systems on marker stability during total knee arthroplasty computer navigation.

Objective: This study investigated different infrared marker reference base attachments in cadaveric bone and their effects on alignment outcome when different loads were applied.

Material And Methods: Five cadaveric specimens were used to test four reference base attachments: a locking one-pin (4.0 mm and 5.

Enhancing femoral cement fixation in total knee arthroplasty.

Several factors have been shown to be associated with early development of radiolucent lines at the bone-cement interface in total knee arthroplasty (TKA). The posterior condylar surfaces, in particular, seem subject to poor cement technique, which could lead to early loosening. This study compares two cementation techniques in TKA, with respect to depth of cement penetration and radiolucency in the posterior condyles.

A radiographic study of the detection limits of bone-cement remnants in total joint arthroplasty.

Management of an infected hip prosthesis typically requires that all associated cement be removed. In the absence of gross mantle loosening, the surgeon frequently resorts to intraoperative radiographs to assess the completeness of removal. For this reason, we undertook a study to determine limits of detection of retained cement by routine radiography.

Preoperative administration of epoetin alfa to total joint arthroplasty patients.

Epoetin alfa is indicated to reduce allogeneic transfusions in patients undergoing major operations. This study included 40 patients undergoing total joint arthroplasty who received 600 IU/kg doses of epoetin alfa 21, 14, and 7 days preoperatively. Statistically equal matches were obtained according to preoperative hemoglobin, operation, sex, and age.

Reliability and validity of a new caliper for measuring patellar thickness.

The process of patellar resurfacing during total knee arthroplasty involves measuring patellar thickness. The optimal residual patellar bone thickness has been questioned. The surgeon's ability to measure patellar thickness currently rests on a standard caliper.