< Back Dr. Enes KANAY Unicameral Bone Cyst (UBC) Unicameral bone cyst (UBC) is a benign, fluid-filled intramedullary lesion typically located in the metaphysis or diaphysis of long bones in children and adolescents. It is usually unilocular and adjacent to the cortex. Pathological fracture is the most common presentation. 1.Associated Conditions UBC may coexist with other lesions: Secondary aneurysmal bone cyst (ABC) Fibrous dysplasia Post-infectious cystic lesions Post-traumatic intramedullary cysts 2. Epidemiology Age: 5–15 years Sex: More common in males (~2:1) Most common sites: Proximal humerus (50–60%), proximal femur (25–30%) Rarely in other long bones, pelvis, or calcaneus 3. Pathogenesis The exact etiology is unclear; proposed mechanisms include intramedullary circulation disturbance and venous obstruction, leading to increased intramedullary pressure and cyst formation. Persistent fluid communication with the growth plate is seen in some cases. 4. Clinical Features Usually asymptomatic Most often presents with pathological fracture Pain typically related to fracture Cortical thinning in large cysts may cause deformity 5. Imaging Radiograph : Metaphyseal or diaphyseal intramedullary location Unilocular, well-defined, homogeneous radiolucency Marked cortical thinning “Fallen fragment sign” (bone fragment within cyst after fracture) CT : Shows cyst wall and cortical thinning MRI : T2 hyperintense fluid; thin cyst wall; septa are uncommon Simple bone cysts typically appear as well-defined, centrally located, intramedullary lucent lesions within the metaphysis of long bones, most often the proximal humerus or femur. They demonstrate a narrow zone of transition, thin sclerotic margins, and may cause mild endosteal expansion or cortical thinning without cortical destruction or periosteal reaction. On plain radiographs, they are usually unilocular, although pseudotrabeculation may occasionally be seen. In the presence of a fracture, a fallen fragment sign or rising bubble sign may be visible. CT confirms the cystic nature and extent of the lesion but adds little diagnostic advantage. On MRI, simple bone cysts show low signal intensity on T1-weighted and high signal on T2-weighted sequences, reflecting their fluid content. Post-contrast images demonstrate only thin peripheral enhancement corresponding to the cyst wall, without solid or nodular components. There is typically no marrow or soft-tissue edema, helping distinguish SBCs from more aggressive cystic or neoplastic processes. 6. Histology Gross : Thin-walled, unilocular, fluid-filled cyst Lined by fibrous tissue; inner surface smooth Microscopic : Thin cyst wall of fibrovascular connective tissue Sparse fibroblasts, macrophages, and foam cells within wall Hemosiderin deposits and cholesterol clefts may be present Variable inflammatory cell infiltrate Occasional new bone trabeculae within wall Differential Diagnosis : Aneurysmal bone cyst, intraosseous ganglion, fibrous dysplasia 7. Treatment and Natural History Small/asymptomatic : Observation Large/high fracture risk : Minimally invasive: Steroid injection, bone marrow aspirate injection Surgical: Curettage + bone graft ± internal fixation Recurrence rate: 10–30%; follow-up until growth plate closure recommended Coronal MRI images of the proximal humerus demonstrate a centrally located, well-defined intramedullary cystic lesion with homogeneous low signal on T1-weighted and high signal on T2-weighted images. The lesion shows thin peripheral enhancement after gadolinium administration, without internal solid components, cortical breach, or periosteal reaction. Findings are characteristic of a simple bone cyst (unicameral bone cyst). Previous Next

< Back Pilon Fractures pilon-fractures Previous Next

< Back Radial Head Fractures radial-head-fractures Previous Next

< Back Alper DUNKI Articular Cartilage Articular cartilage is a specialised connective tissue covering joint surfaces, providing a low-friction, load-bearing interface essential for joint motion and integrity. Structure and Composition: Composed of chondrocytes embedded in an extracellular matrix (ECM) of collagen (mainly type II) , proteoglycans , and water (up to 80%). Organised into four histological zones: Superficial (Tangential) Zone – flat chondrocytes, high collagen, resist shear Middle (Transitional) Zone – rounder chondrocytes, high proteoglycans Deep Zone – vertical collagen fibres, resist compressive forces Calcified Zone – anchors cartilage to subchondral bone Functions: Provides smooth articulation and shock absorption Distributes mechanical loads across the joint Lacks blood vessels, lymphatics, and nerves → limited intrinsic repair capacity Biomechanical Properties: Viscoelastic behaviour due to proteoglycan-water interaction Maintains joint congruity and lubrication Damage leads to increased friction and joint degeneration Injury and Degeneration: Can occur due to trauma , overuse , or inflammatory conditions Partial-thickness defects often do not heal Full-thickness defects may undergo limited fibrocartilage repair Assessment Modalities: MRI with cartilage-sensitive sequences (e.g., dGEMRIC, T2 mapping) Arthroscopy provides direct visualisation Scoring systems : Outerbridge classification, ICRS grading Repair Techniques: Microfracture : promotes fibrocartilage repair Osteochondral autograft/allograft transplantation Autologous chondrocyte implantation (ACI) Matrix-assisted ACI (MACI) Biologic adjuncts (e.g., PRP, stem cells) under research Orthopaedic Relevance: Central to sports injuries , osteoarthritis , and joint preservation surgery Success of cartilage procedures depends on patient age , defect size , and mechanical alignment Previous Next

< Back Alper DUNKI Bone Grafts, BMP, and Bone Substitutes Purpose: Enhance fracture healing, treat nonunion, arthrodesis, fill bone defects Mechanisms: Osteogenesis → viable bone-forming cells Osteoinduction → growth factors (e.g., BMP) Osteoconduction → scaffold for bone growth Gold Standard: Autograft (provides all three mechanisms) Alternatives: Allograft, DBM, ceramics (HA, β-TCP), collagen, bone marrow aspirate BMPs: rhBMP-2 & rhBMP-7 → used in spinal fusion, long bone nonunion Limitations: Risk of ectopic bone, swelling, variable efficacy, cost issues Adjuncts: Electromagnetic stimulation, low-intensity ultrasound (experimental) Bone Healing Primary healing Occurs with fixation that provides absolute stability. In open reduction and internal fixation, disruption of the fracture hematoma may delay early healing. Direct healing occurs through cortical remodeling. Areas lacking direct contact are initially filled with woven bone, which later remodels into lamellar bone. Secondary healing Takes place in the periosteum and surrounding soft tissues. Both endochondral and intramembranous ossification may occur simultaneously. Phases of bone healing Inflammation: Hematoma formation, migration of inflammatory cells, angiogenesis, BMP-mediated mesenchymal stem cell differentiation. Reparative phase: Formation of woven bone (soft callus), osteoid seam, cartilaginous bridge, and calcification. Remodeling phase: Resorption and formation occur concurrently; Wolff’s law is the guiding principle. Factors impairing healing: Excessive instability, poor vascularity, periosteal damage, use of NSAIDs/corticosteroids, smoking, systemic metabolic bone disease. 2. Role of Bone Grafts Indications: Fracture healing, delayed union/nonunion, arthrodesis, repair of bone defects. Physiologic mechanisms: Osteogenesis: Provides viable bone-forming cells (e.g., autograft, bone marrow aspirate). Osteoinduction: Provides factors stimulating cell differentiation (e.g., BMP). Osteoconduction: Provides a scaffold for new bone formation (e.g., cancellous bone). 3. Bone Graft Materials Autograft Harvested from the same individual; considered the gold standard with osteogenic, osteoinductive, and osteoconductive properties. Types: Cortical (high structural support, low cellular/factor content), cancellous (low structural support, high cellular/factor content), corticocancellous. Iliac crest graft is most common; complications include pain, hematoma, nerve injury, infection, fracture. Local autograft (e.g., lamina after laminectomy) is limited in quantity. Allograft Harvested from cadavers; weak osteogenic potential; sterilization reduces osteoinductivity. Types: Fresh (rarely used), frozen, freeze-dried, demineralized bone matrix (DBM). DBM: Mineral removed, collagen structure preserved; osteoinductive potential varies with processing, provides no structural support. Autologous bone marrow aspirate Source of mesenchymal stem cells; used alone or combined with grafts. Collagen Supports mineralization and vascularization; does not provide structural support; often used as a carrier. Inorganic compounds and bioceramics HA, β-TCP, bioactive glass; compressive strength, osteoconductive; resorption rates differ. 4. Bone Morphogenetic Proteins (BMP) Members of the TGF-β superfamily; only certain types are osteoinductive (e.g., BMP-2, BMP-7). Recombinant forms: rhBMP-2 (used in spinal fusion, tibial fractures), rhBMP-7 (used in long bone nonunions). Efficacy: Comparable clinical outcomes to ICBG; some studies report higher radiological fusion rates. Complications: Ectopic bone formation, regional swelling, increased complication rates with some fusion techniques. 5. Combined Graft Use Different grafts may be combined to complement properties or compensate for insufficient volume (e.g., cortical allograft + DBM + local bone). 6. Other Methods to Enhance Bone Healing Electromagnetic stimulation: Based on alteration of bioelectric potentials at the healing site; clinical efficacy is variable. Types: Pulsed electromagnetic field, capacitive coupling, direct current stimulation. Low-intensity ultrasound: Potentially beneficial; not widely used in clinical practice. References 1. Zhang, J., Wang, Y., & Jin, D. (2025). Research progress of bone grafting: A comprehensive review. International Journal of Nanomedicine, 2. Von Benecke, J. P., & ark. (2024). A narrative review on recombinant human bone morphogenetic protein-2: Where are we now? Cureus , Article e.g. 2024. Previous Next

< Back Proximal Humerus Proximal humerus fractures are common in elderly patients, often related to osteoporosis and low-energy trauma such as a fall from standing height. These fractures represent approximately 5% of all fractures and are the third most common in elderly patients. The Neer classification is commonly used, based on the number of displaced parts (>1 cm or >45° angulation). Non-displaced fractures are treated conservatively with early mobilisation. Surgical options for displaced fractures include ORIF with locking plates, intramedullary nails, and shoulder arthroplasty (hemiarthroplasty or reverse TSA) in cases of complex multi-part fractures or poor bone quality. Key complications include avascular necrosis, stiffness, malunion, and rotator cuff dysfunction. proximal-humerus Previous Next

< Back Nonunion & Malunion Management nonunion-malunion-management Previous Next

< Back Monteggia Fractures monteggia-fractures Previous Next

Literature Update Topics Long-Term Patient-Reported Outcomes After Nonoperative Treatment of Distal Radial Fractures: What CT-Based Gaps and Step-Offs Can Be Accepted? Journal: European Journal of Trauma and Emergency Surgery (2025) The historical 2 mm “rule” was originally based on plain radiographs linking step-off > 2 mm to radiographic osteoarthritis, not to functional outcome. Modern CT evaluation allows more precise measurement of intra-articular displacement, revealing that slightly greater incongruities can be tolerated without long-term disability. Nonoperative management remains valid for selected moderately displaced fractures after shared decision-making, potentially reducing unnecessary surgeries. 🧠 Key Points: CT-based evaluation shows that intra-articular gaps up to 4 mm and step-offs up to 2 mm can be safely managed nonoperatively , achieving excellent 10-year functional outcomes. The traditional 2 mm rule for surgical indication, derived from plain radiographs, may be overly restrictive in modern CT-guided fracture assessment. DOI: 10.1007/s00068-025-02954-z Quality of Life and Outcomes After Treatment Failure for Recurrent PJI of TKA The Journal of Arthroplasty (2025) Multicenter retrospective study comparing outcomes of above-knee amputation (AKA), permanent spacers, and knee arthrodesis in patients with recurrent periprosthetic joint infection (PJI) of the knee after failed revisions. A total of 86 patients (35 AKA, 43 spacer, 8 arthrodesis) were evaluated for quality of life (SF-36), pain (VAS, DN4), complications, and functional outcomes. 🧠 Key Points AKA patients had better quality of life scores (higher SF-36 general health and role-physical scores) compared to spacers. Pain relief was superior in AKA (lower VAS and DN4) than both spacer and arthrodesis. Complication and reoperation rates were highest with spacers (53% and 42%) vs. lowest with AKA (14% each). Functional mobility: AKA patients more often walked >1 mile (26% vs. 5% with spacer) and were more frequently able to drive (42% vs. 23%). Mortality and reinfection rates were similar across groups at 2 years. Conclusion: AKA should not only be a last resort —it offers better pain control, fewer complications, and improved QoL in selected patients. doi.org/10.1016/j.arth.2025.08.017 Short-term contemporary outcomes for staged versus primary lower limb amputation in diabetic foot disease Journal of Vascular Surgery (2020) In the setting of infected diabetic foot disease, a staged lower extremity amputation achieves quality outcomes superior to a one-stage amputation, despite the former cohort’s greater illness acuity level. SA should be considered in all diabetic patients presenting with active foot infection. 🧠 Key Points: Staged amputation (SA) was compared with primary amputation (PA) in diabetic foot patients with severe infections. • SA showed lower 30-day readmission (17% vs 27%) and 30-day unplanned reoperation (11% vs 13%). • Length of stay and major adverse cardiovascular events were similar. • SA may provide better short-term quality outcomes in selected patients. doi.org/10.1016/j.jvs.2019.10.083 The Femoral Head Edema Zone: A Novel Classification Scheme to Better Predict Osteonecrosis Progression The Journal of Arthroplasty (2025) Retrospective single-institution study evaluating whether a new Edema Zone classification (based on extent of femoral head edema on MRI) predicts conversion to total hip arthroplasty (THA) after core decompression for osteonecrosis of the femoral head (ONFH). Compared against the established Japanese Investigation Committee (JIC) classification. 🧠 Key Points Study Population: 94 hips with ONFH treated with core decompression (20 converted to THA within 26 months, 74 did not). Edema Zone vs JIC: Edema Zone classification correlated with THA conversion, while JIC did not (P < 0.001 vs P = 0.83). Predictive accuracy: AUC 0.71 for Edema Zone vs 0.52 for JIC → better prognostic tool . Reliability: Excellent inter-rater reliability for Edema Zone (κ = 0.87), outperforming JIC and other systems. Risk association: Higher Edema Zone grades (≥3) had significantly greater THA conversion rates (e.g., 67% for grade 4). Clinical implication: The Edema Zone classification provides a simple, MRI-based, reliable system to guide surgical decision-making and avoid ineffective core decompressions in high-risk patients. doi.org/10.1016/j.arth.2025.08.035 Optimal Tightrope Positioning for Adequate Syndesmotic Stabilization in Simulated Syndesmotic Injuries Foot & Ankle Orthopaedics (2025) Use of syndesmotic suture button fixation has gained in popularity for treating an injury to the tibiofibular syndesmosis. Biomechanical fixation stability with suture button device (TightRope; Arthrex, Naples, FL) placed at 4 distances from the tibiotalar joint line (0.5, 1.5, 2.5, and 3.5 cm) and 3 trajectories (anterior, medial, and posterior) were studied using cadaveric lower extremities with created syndesmotic injuries. Fixation placed at 0.5 or 1.5 cm from the joint line in medial or posterior trajectories resulted in the lowest increases in fibular rotation. More proximal or anterior placements led to increased fibular motion and decreased rotational stability. 🧠 Key Points Syndesmotic suture button placement 0.5–1.5 cm from the joint line provides the most rotationally stable fixation. Medial and posterior trajectories are more stable than anterior placements. Proximal placements beyond 1.5 cm increase fibular motion and reduce stability. Ankle width changes were minimal but increased slightly with anterior or proximal placement. Biomechanical cadaveric testing simulates in vivo weightbearing and rotational loads. DOI: 10.1177/24730114251342243 Mirels' Score for Upper Limb Metastatic Lesions: Do We Need a Different Cutoff for Recommending Prophylactic Fixation? JSES International (2022), Vol 6(4): 675–681 Conclusions: This study demonstrates moderate to substantial agreement between and within raters using Mirels’ score on upper limb radiographs. However, Mirels’ score had a poor ensitivity and specifity in predicting upper extremity fractures. Until a more valid scoring system has been developed, based on our study, we recommend a Mirels’ threshold of 7/12 for considering prophylactic fixation of impending upper limb pathologic fractures. This contrasts with the current 9/12 cutoff, which is recommended for lower limb pathologic fractures. 🧠 Key Points: Mirels score was originally proposed for metastatic lesions in the lower extremities; its applicability to the upper extremity has been questioned. A score of ≥7 may be sufficient to consider prophylactic fixation in upper extremity metastases. This was a retrospective study analyzing 138 cases. DOI:10.1016/j.jseint.2022.03.006 Body Mass Index > 40 Is Not Correlated With Early Complications in Patients Undergoing Primary Total Joint Arthroplasty at an Ambulatory Surgical Center The Journal of Arthroplasty (2025) Retrospective study of 2,367 patients undergoing primary total hip or knee arthroplasty (THA/TKA) at an ambulatory surgical center. Patients were stratified by BMI groups (normal, overweight, obesity classes I–III including ≥40). Outcomes assessed: early (24h) and 1–90 day complications, perioperative times, PACU course, and pain scores. 🧠 Key Points Complication rates at 24h and 1–90 days were not significantly different across BMI groups, including BMI ≥40. Operative and pre-op times were longer in higher BMI patients, but PACU discharge was earlier . Pain scores before discharge were higher in obesity groups, but without increased adverse events. Estimated blood loss was similar across BMI groups. Conclusion: With proper preoperative optimization, BMI ≥40 should not be an exclusion criterion for outpatient TJA; outcomes are comparable to lower BMI patients. doi.org/10.1016/j.arth.2025.08.065 Alignment Techniques in Total Knee Arthroplasty Journal of Joint Surgery and Research (2023), Vol 1: 108–116 Wide range of clinical results exist for new alignment techniques in the short term. The safe range of alignment for long-term survivorship remains unknown. Further high-quality studies should be performed to warrant the widespread use of new alignment techniques. 🧠 Key Points: • Mechanical alignment remains standard in TKA but doesn’t consider individual pre-arthritic alignment. • Newer techniques (kinematic, restricted, inverse, modified, functional alignment) aim to restore native joint line and improve satisfaction. • Most RCTs show comparable or better short-term outcomes with novel techniques. • Long-term survivorship data are still lacking; alignment “safe zones” remain debated. • Robotic and navigation systems are key tools in implementing newer alignment methods. doi.org/10.1016/j.jjoisr.2023.02.003

< Back Ligament Injuries (UCL, LCL) elbow-ligament-injuries Previous Next

Trauma General Principles 1.Polytrauma Evaluation 2.ATLS & Resuscitation 3.Compartment Syndrome 4. Crush Syndrome 5. Open Fracture Management Upper Extremity 1. Clavicle Fractures 2. Proximal Humerus 3. Humeral Shaft 4. Supracondylar (Peds) 5. Elbow Injuries 6. Forearm (Monteggia, Galeazzi) 7. Distal Radius/Ulna 8. Scaphoid 9. Hand & Fingers Lower Extremity 1. Pelvic Ring 2. Acetabular Fracture 3. Hip Fractures 4 .Femoral Shaft 5. Tibial Plateau 6. Tibial Shaft 7. Ankle Fractures 8. Calcaneus 9. Talus 10. Foot & Toes Special Considerations 1. Pediatric Trauma 2. Geriatric Patterns 3. Classifications 4. Surgical Timing 5. Damage Control

< Back Imaging Q shoulder-elbow-imaging Previous Next