Introduction A nonunion is an arrest in the fracture repair process progressive evidence of non healing of a fracture of a bone a delayed union is generally defined as a failure to reach bony union by 6 months post-injury this also includes fractures that are taking longer than expected to heal (ie. distal radial fractures) large segmental defects should be considered functional non-unions Pathophysiology multifactorial most commonly, inadequate fracture stabilization and poor blood supply lead to nonunion infection eradication needs to occur along with the achieving fracture union smoking location scaphoid, distal tibia, base of the 5th metatarsal are at higher risk for nonunion because blood supply in these areas pattern segmental fractures and those with butterfly fragments increased risk of nonunion like because of compromise of the blood supply to the intercalary segment Classification Types of nonunion septic nonunion caused by infection CRP test as the most accurate predictor of infection pseudoarthrosis hypertrophic nonunion caused by inadequate stability with adequate blood supply and biology abundant callous formation without bridging bone typically heal once mechanical stability is improved atrophic nonunion caused by inadequate immobilization and inadequate blood supply oligotrophic nonunion produced by inadequate reduction with fracture fragment displacement Presentation Symptoms important to discern injury mechanisms, non operative interventions, baseline metabolic, nutritional or immunologic statuses and use of NSAIDs and/or nicotine containing products assess pain levels with axial loading of involved extremity Physical exam important to complete a thorough neurovascular exam, including the status of the soft tissue envelope assess mobility of the nonunion assess extremity for the presence of deformity Imaging Radiographs plain radiographs are the cornerstone for evaluation of fracture healing; four views should be included full length weight bearing films should obtained if a limb length discrepancy is present CT if the status of union is in question, a CT scan should be obtained; hardware artifact may limit utility of the CT scan Treatment Nonoperative fracture brace immobilization bone stimulators contraindications synovial pseudoarthroses mobile nonunions greater than 1 cm between fracture ends Operative infected nonunion often associated with pseudoarthrosis chance of fracture healing is low if infection isn't eradicated staged approach often important modalities need to remove all infected/devitalized soft tissue use antibiotic beads, VAC dressings to manage the wound with significant bone loss, bone transport may be an option muscle flaps can be critical in wound management with soft tissue loss pseudoarthrosis may be found in association with infection modalities removal of atrophic, non-viable bone ends internal fixation with mechanical stability maintenance of viable soft tissue envelope hypertrophic nonunions often have biologically viable bone ends issue with fixation, not the biology modalities internal fixation with application of appropriate mechanical stability oligotrophic nonunions often have biologically viable bone ends may require biological stimulation modalities internal fixation atrophic nonunions often have dysvascular bone ends modalities need to ensure biologically viable bony ends are apposed fixation needs to be mechanically stable bone grafting autologous iliac crest (osteoinductive) is gold standard BMPs osteoconductive agents (ie. crushed cancellous chips, DBM) establishment of healthy soft tissue flap/envelope Techniques Bone stimulators four main delivery modes of electrical stimulation direct current decrease osteoclast activity and increase osteoblast activity by reducing oxygen concentration and increasing local tissue pH capacitively coupled electrical fields (alternating current, AC) affect synthesis of cAMP, collagen and calcification of carilage pulsed electromagnetic fields cause calcification of fibrocartilage combined magnetic fields bone simulators work through induction coupling, which stimulates bone growth through the following direct effects increasing expression of BMP7 increasing expression of BMP7 increasing expression of BMP2 increasing expression of TGF-beta1 increasing expression of osteoblasts proliferation
QUESTIONS 1 of 8 1 2 3 4 5 6 7 8 Previous Next (SBQ20TR.23) Figure A is the radiograph of a 52-year-old male who underwent open reduction and internal fixation (ORIF) of a both bone forearm fracture six months prior. He complains of persistent pain at the ulna fracture site. His C-reactive protein and erythrocyte sedimentation rate are within normal limits. What is the most appropriate definitive treatment for this patient? QID: 215831 FIGURES: A Type & Select Correct Answer 1 Observation with repeat radiographs in 6 months 2% (19/854) 2 Short arm cast immobilization 0% (1/854) 3 Removal of hardware with intramedullary nail placement 1% (12/854) 4 Revision ORIF without graft 20% (169/854) 5 Revision ORIF with autograft 76% (650/854) L 2 Question Complexity E Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 5 Review Tested Concept Review Full Topic Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (OBQ18.217) A 32-year-old man underwent open reduction and internal fixation for an open radial shaft fracture 6 months ago. He is now experiencing fevers and chills at night and pain and swelling over the surgical site. A current radiograph is depicted in Figure A. What is the most accurate laboratory test for assessing his most likely diagnosis? QID: 213113 FIGURES: A Type & Select Correct Answer 1 Interleukin-1 2% (39/1985) 2 White blood cell (WBC) count with differential 3% (52/1985) 3 C-Reactive Protein (CRP) 79% (1563/1985) 4 Interleukin-6 14% (268/1985) 5 Erythrocyte sedimentation rate (ESR) 2% (48/1985) L 2 Question Complexity A Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 3 Review Tested Concept Review Full Topic Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (OBQ15.250) Induction coupling stimulates bone growth through all of the following direct effects EXCEPT: QID: 5935 Type & Select Correct Answer 1 Increased proliferation of osteoblasts 4% (146/3475) 2 Decreased osteoclast differentiation 47% (1643/3475) 3 Increase release of TGF-beta1 25% (870/3475) 4 Increased expression of BMP2 6% (200/3475) 5 Increased expression of BMP7 17% (589/3475) L 4 Question Complexity C Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 2 Review Tested Concept Review Full Topic Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK
All Videos (7) Podcasts (1) Login to View Community Videos Login to View Community Videos 2022 Bobby Menges Memorial HSS Limb Deformity Course Bone Defect Management: BT Nail vs. Cable Transport - Stephen Matthew Quinnan, MD Stephen Quinnan Basic Science - Nonunion and Bone Defects 12/9/2022 103 views 4.0 (2) Bobby Menges Memorial HSS Limb Deformity Course 2021 Outpatient Nonunion Pathway - Joseph R. Hsu, MD Joseph Hsu Trauma - Nonunion and Bone Defects B 5/17/2021 678 views 0.0 (0) Login to View Community Videos Login to View Community Videos 2021 Orthopaedic Trauma & Fracture Care: Pushing the Envelope All Internal Bone Transport - Geoffrey Marecek, MD Geoffrey Marecek Basic Science - Nonunion and Bone Defects A 2/8/2021 1212 views 3.7 (3) Basic Science | Nonunion and Bone Defects Basic Science - Nonunion and Bone Defects Listen Now 18:32 min 7/3/2020 716 plays 4.5 (2) See More See Less
Bobby Menges Memorial HSS Limb Deformity Course 2021 Ankle Deformity s/p Infection in 16F (C101706) S. Robert Rozbruch Basic Science - Nonunion and Bone Defects A 1/27/2021 7583 27 9 Proximal Third Tibia Fx Nonunion in 62F (C101373) Jerrod Steimle Benjamin C. Taylor Basic Science - Nonunion and Bone Defects A 1/30/2020 9217 21 14 Femoral shaft nonunion in 26F (C101308) John Verre Basic Science - Nonunion and Bone Defects E 10/17/2019 258 9 4 See More See Less