Biomechanics
– See: – Characteristics of Metals and Implants: – Elastic Strain – Metal Fatigue – Plates – Polyethylene – Screws – Strain – Stress – Ultimate Tensile Strength: … Read more
Data Trace Editor
Biomechanics of ACL
– See: Biomechanics Menu: – Anatomy of the ACL: – Biomechanics: – ultimate tensile load: 2160 ± 157 N – stiffness: 242 ± 28 N/mm; – passive knee extension produces forces along ACL only during last 10 degrees of knee extension; – hyper-extension: … Read more
Biomechanics of the Patello-Femoral Joint
– See: Role of Knee Joint During Gait: – Discussion: – patella increases the mechanical advantage of extensor muscles by transmitting forces across knee at greater distance (moment) from axis of rotation; – increases functional lever arm of quads as well as changing direction of pull of quad mechanism; … Read more
Biopsy of Musculoskeletal Tumors
– Discussion: – may be accomplished with a large needle or by open surgical methods; – things to consider before biopsy: – has the workup established metastatic dz (most common in patients over 40) vs isolated bone / soft tissue tumor vs infection (osteomyelitis); – studies that may be performed prior to biopsy: … Read more
Bigelow’s Maneuver: for Posterior Hip Dislocation
– See: – Closed Reduction – Gravity Method of Stimson – Discussion: – pt lies supine, & assistant applies countertraction by downward pressure on the ASIS; – surgeon grasps affected limb at ankle w/ one hand, places opposite forearm behind the knee, and applies longitudinal traction in line of deformity; – adducted & internally rotated … Read more
Bilateral InterFacet Dislocation
– Discussion: – integrity of all ligaments of cervical canal is lost, including posterior ligaments, anterior & posterior longitudinal ligaments, disc, and articular facet joints; – this type of injury occurs only when middle & posterior ligamentous structures are disrupted; – there are typically no frxs of facets because … Read more
Bilateral Knee Replacement
– Discussion: – multiple reviews have demonstrated that simultaneous vs. staged knee total knee arthroplasty offers similar results with lower overall costs. – prominent studies include Morrey, et al (1987) (N=1253), Ranawat, et al (1994) (N=155), Ritter (1987) (N=264), Brotherton, et al (1986)(N=94), and McLaughlin and Fisher (1985) (N=136). – above studies … Read more
BILIRUBIN
– Total: <0.2-1.0 mg/dL; Direct: <0.2 mg/dL; Indirect: <0.8 mg/dL Increased Total: Hepatic damage (Hepatitis, Toxins, Cirrhosis), Bililary Obstruction (stone or tumor), Hemolysis, Fasting; Increased Direct (Conjugated): Biliary obstruction/cholestasis (gallstone, tumor, stricture), Med induced Cholestasis, Dubin Johnson and Rotor’s syndrome; Increased Indirect (Unconjugated): “Hemolytic jaundice” from Transfusion RXN, HbS ect.; Gilbert’s dz, Crigler Najjar syndrome
Biodegradable Fixation of Ankle Fractures
– See: Bioabsorble Implant Discussion Fixation with Bioabsorbable Screws for the Treatment of Fractures of the Ankle. Surgical treatment of fracture-dislocations of the ankle joint with biodegradable implants: a prospective randomized study. Biodegradable fixation of ankle fractures. Complications in a prospective study of 25 cases. Intense granulomatous inflammatory lesions associated with absorbable internal fixation devices … Read more
Bicondylar Planteau Frx: Indirect Reduction
– Indirect Reduction Stratedgy: – statedgy forgoes attempts at meniscal reduction (or repair), ligamentous repair, or direct joint reduction; – longitudinal traction is used to align proximal tibial condyles over shaft; – depressed fragments are reduced w/ a bone tamp thru cortical window; – frx reduction is … Read more