< Back Dr. Alper DUNKI University of Health Sciences, Istanbul, Umraniye Research and Education Hospital Dr. Alper Dünki completed his medical education at Yeditepe University Faculty of Medicine and residency training in Orthopaedics and Traumatology at Tekirdağ Namık Kemal University. His primary fields of interest include orthopaedic oncology and trauma. He currently serves as an orthopaedic surgeon at SBÜ Ümraniye Training and Research Hospital. Dr. Dünki is a member of TOTBİD, the Foot and Ankle Surgery Society, and the Young Orthopaedic Surgeons Group (AGUH). Oncologic Orthopaedics alperdunki@gmail.com Previous Next

< Back Hallux Valgus hallux-valgus Previous Next

< Back Mirels' Score for Upper Limb Metastatic Lesions: Do We Need a Different Cutoff for Recommending Prophylactic Fixation? 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. JSES International (2022), Vol 6(4): 675–681 DOI:10.1016/j.jseint.2022.03.006 Previous Next

< Back Dr. Ali Erkan Yenigul Principles of Surgical Resection & Margins Tumour resection aims to achieve oncologic control while preserving function; margin status is critical for local recurrence risk. Historical Background Pre-1940s → Amputation was standard treatment. 1940s sonrası → Tumour resection 1970s → Chemotherapy + Radiotherapy + Limb-sparing surgery standard of care. Basic Principles Wide surgical margin = most important factor for local control. All imaging must be completed before surgery. Surgical planning should be based on imaging close to surgery date . Enneking’s Margin Classification Intralesional Curettage / piecemeal debulking / Macroscopic disease remains Marginal Shelling out via pseudocapsule- reactive zone / May leave satellite or skip lesions Wide En bloc with cuff of normal tissue / Adequate, but skip lesions possible Radical En bloc removal of whole compartment / No residual local disease Natural Barriers Bone: Cortical bone, articular cartilage Joint: Articular cartilage, capsule Soft tissue: Fascial septa, tendon origins/insertions Barrier effect : Fascia, tendon sheath, vascular sheath, cartilage act as protective margins Critical Points in Limb-Sparing Surgery Poor biopsy incision Major vascular involvement Motor nerve sacrifice Preoperative infection Expected poor motor function after resection ➡️ These complicate but do not always contraindicate limb-sparing surgery. Advanced Techniques Microsurgical reconstruction Tendon transfers, nerve/vessel grafts Flap coverage after large resections Role of Adjunctive Therapies Neoadjuvant chemotherapy/radiotherapy → may shrink tumour, improve margin status. Wide margins still required even after neoadjuvant treatment. Practical Margin Rules Bone tumours: ≥ 3 cm bone marrow margin on T1 MRI. Soft tissue tumours: Aim for ≥ 2 cm margin. References Enneking WF. Musculoskeletal Tumor Surgery. New York: Churchill Livingstone; 1983. Simon MA, Springfield DS. Surgery for Bone and Soft-Tissue Tumors. Philadelphia: Lippincott-Raven; 1998. Healey JH, Lane JM. Operative Techniques in Orthopaedic Surgical Oncology. Philadelphia: Lippincott Williams & Wilkins; 1996. (For the figures and the margin classification) Mankin HJ, Hornicek FJ. Diagnosis, classification, and management of soft tissue sarcomas. Cancer Control. 2005;12(1):5–21. O’Donnell RJ, Springfield DS, Motwani HK, et al. Recurrence of giant-cell tumors of the long bones after curettage and packing with cement. J Bone Joint Surg Am. 1994;76(12):1827–33. Previous Next

< Back Torticollis torticollis Previous Next

< Back Slipped Capital Femoral Epiphysis (SCFE) slipped-capital-femoral-epiphysis-scfe Previous Next

< Back Joint Preservation vs Replacement Previous Next

< Back Thoracic Spine Fractures kocaelispor Previous Next

< Back Forearm Malunion & Osteotomy forearm-malunion-osteotomy Previous Next

< Back Postoperative Rehabilitation Previous Next

< Back Microsurgery Basics microsurgery-basics Previous Next

< Back Dr. Omer POLAT Anatomy & Biomechanics Overview The human spine is a complex, segmented column providing both mobility and stability for the body. It consists of 33 vertebrae: 7 cervical, 12 thoracic, 5 lumbar, 5 fused sacral, and 4 fused coccygeal segments. These vertebrae are interconnected through discs, ligaments, and muscles, forming a biomechanically dynamic structure that supports axial load, enables movement, and protects the spinal cord. Each vertebra comprises a vertebral body and a posterior arch. The body, primarily cancellous bone, functions as the main weight-bearing element. The posterior arch, composed mainly of cortical bone, includes pedicles, laminae, and spinous and transverse processes, which provide attachment points for ligaments and muscles. Between adjacent vertebral bodies lie the intervertebral discs, acting as flexible cushions that absorb compressive forces while allowing controlled motion. Cervical Spine The cervical spine includes seven vertebrae (C1–C7) , forming a lordotic curve in the sagittal plane. C1 (Atlas): ring-shaped, lacks a body, and transmits cranial load through its lateral masses. The atlanto-occipital joint allows flexion–extension (“nodding”) but limited rotation. C2 (Axis): characterized by the odontoid process (dens) , which forms a pivot for C1 rotation, allowing approximately 50% of total cervical rotation. C7: has a prominent, non-bifid spinous process; vertebral arteries typically do not pass through its transverse foramen. Cervical motion includes flexion, extension, lateral bending, and rotation , made possible by the facet orientation and ligamentous configuration. Major cervical ligaments include: Anterior longitudinal ligament (ALL): runs along anterior vertebral bodies, limits hyperextension. Posterior longitudinal ligament (PLL): along posterior vertebral bodies, limits hyperflexion. Ligamentum flavum (LF): connects adjacent laminae; elastic fibers assist in returning to extension. Interspinous and supraspinous ligaments: resist flexion. Nuchal ligament: a continuation of the supraspinous ligament from C1–C7, providing attachment for deep cervical muscles. Transverse ligament of the atlas: stabilizes the dens, maintaining atlantoaxial integrity. Thoracic Spine Composed of 12 vertebrae (T1–T12) , the thoracic spine is kyphotic and articulates with the ribs via costovertebral and costotransverse joints . Typical vertebrae (T2–T8) are heart-shaped and smaller than lumbar bodies. Facet joints are oriented in the coronal plane , permitting limited rotation but restricting flexion–extension. The rib cage enhances structural rigidity, reducing mobility but protecting thoracic organs. Normal thoracic kyphosis ranges between 20° and 50° (average ~35°). Lumbar Spine The five lumbar vertebrae (L1–L5) form a lordotic curve , designed to bear increasing axial loads toward the sacrum. Vertebral bodies enlarge caudally to support greater weight. Facet joints are oriented in the sagittal plane , allowing flexion–extension while limiting rotation. The vertebral foramen is triangular, smaller than cervical but larger than thoracic. Intervertebral discs constitute about 20% of total spinal length , consisting of the annulus fibrosus , nucleus pulposus , and cartilaginous endplates . Discs are largely avascular in adults , adapted for compression but less resistant to torsion. Under normal conditions: The vertebral body carries ~80% of axial load. Facet joints bear the remaining ~20%. In degenerative disc disease, disc height loss shifts up to 70% of load to the facets, increasing posterior stress. Flexion contribution: 75% at L5–S1 , 15–20% at L4–L5 , 5–10% at L1–L4 . Ligaments of the Lumbar Spine Lumbar stability depends on both static (ligamentous) and dynamic (muscular) structures. Anterior longitudinal ligament (ALL): limits hyperextension; major stabilizer of the anterior column. Posterior longitudinal ligament (PLL): resists hyperflexion and confines disc herniation, especially posterolaterally. Ligamentum flavum (LF): elastic, connects laminae; thickens with age, contributing to spinal stenosis. Interspinous ligament (ISL): between spinous processes; tenses during flexion. Supraspinous ligament (SSL): connects the apices of spinous processes from C7 to sacrum; resists excessive flexion. Muscles of the Lumbar Spine Lumbar musculature plays a vital role in postural control, motion, and load transfer . Erector spinae group (spinalis, longissimus, iliocostalis): composed mainly of slow-twitch type I fibers; maintain posture and control trunk extension. Multifidus muscle: short, segmental fibers with a large physiological cross-sectional area, providing segmental stability . Rich connective tissue increases endurance and contributes to passive stiffness. Dysfunction or atrophy is strongly linked to chronic low back pain. Sacrum and Coccyx The sacrum consists of five fused vertebrae forming a wedge-shaped bone that articulates laterally with the iliac bones via the sacroiliac joints . The sacral canal continues from the lumbar spinal canal, terminating at the sacral hiatus , where the coccyx begins. There are four pairs of anterior and posterior foramina , through which the sacral spinal nerves exit. The coccyx , formed by fusion of four small vertebrae, represents the vestigial tailbone and provides attachment for pelvic floor muscles. The sacrum serves as the keystone of the pelvis , transferring spinal load to the lower extremities and contributing to the stability of the lumbopelvic complex. References: Gray H, Standring S. Gray’s Anatomy: The Anatomical Basis of Clinical Practice. 42nd ed. Elsevier, 2020. White AA, Panjabi MM. Clinical Biomechanics of the Spine. 2nd ed. Lippincott Williams & Wilkins, 1990. Bogduk N. Clinical Anatomy of the Lumbar Spine and Sacrum. 5th ed. Elsevier, 2012. Adams MA, Dolan P. Spine biomechanics. J Biomech. 2005;38(10):1972–1983. Pal GP, Routal RV. Anatomy and biomechanics of the human vertebral column. Clin Anat. 1999;12(5):324–339. Previous Next