Fracture healing

fracture healing and its medicolegal importance

1. FRACTURE HEALING By Dr.Nafeeya Department Of Forensic Medicine and Toxicology

2. overview Introduction Anatomy of bones Pathophysiology of bone healing Stages of fracture healing Medicolegal importance

3. Introduction Fracture is a break in the structural continuity of bone or periosteum.   Fracture results in loss of its mechanical stability and also partial destruction of blood supply   Fracture healing starts as soon as bone breaks and continues modelling for many years.

4. ANATOMY OF BONES Parts of long bones: Epiphyses: ends of a long bone that ossifies from secondary centers. Diaphysis: shaft of long bones that ossifies from primary center Metaphysis: part of diaphysis[zone of active bone growth] Structural components of bone: Mineralized matrix Osteoblast, osteocytes, osteoclasts Periosteum Endosteum Medullary Cavity Bone Marrow

5. FRACTURE HEALING DIRECT / PRIMARY : When there is direct contact between the bone ends, bone forms directly across the fracture line , by direct extension of osteons. Does not involve formation of fracture callus. Mechanism of bone healing seen when there is no motion at the fracture site (i.e. rigid internal fixation). INDIRECT/SECONDARY: Callus formation This callus is later replaced by bone. Mechanism for healing in fractures that are not rigidly fixed. Bridging periosteal (soft) callus and medullary (hard) callus re-establish structural continuity. It is comparable to healing of soft tissue by filling of gaps with vascular granulation tissue

6. Healing of cancellous bones: Creeping substitution” - New blood vessels can invade trabeculae of cancellous bone and bone opposition may take place directly on to the surface of trabeculum . Heals at the point of direct contact: Cancellous bone certainly can unite very rapidly, but it unites rapidly only at the points of direct contact. No bridging callus : Cancellous bone unites only by contact,not by throwing out callus even when it is cut of due to dense attachment of the periosteum. No death of osteocytes :blood supply is good and large surface area of the trabecular spaces combined with relatively thin trabeculae, keep the osteocytes nourished. Has tendency for late collapse :This lack of callus production by cancellous bone explains the tendency to late collapse which have been distracted.

7. Stages of fracture healing Tissue destruction and hematoma formation[Day-1] Inflamation and cellular proliferation[2weeks] Stage of callus formation[2-3 weeks] Stage of consolidation[3-6 weeks] Stage of remodeling[8-2yrs]

8. HEMATOMA FORMATION-1 Blood vessels torn –haemorrhage A mass of clotted blood (hematoma) forms at the fracture site Site becomes swollen, painful, and inflamed

9. Day-1-Broken bones ,blood clots .

10. INFLAMATION AND CELLULAR PROLIFERATION-2weeks Within [8 hrs-2weeks] inflammatory reaction starts. Proliferation and Differentiation of cells occurs. Secretion of TGF-B , PDGF and various factors.

11. Day 7 - Chondrogenesis and inflammatory response at the fracture site. chondrogenic response. bone formation from the periosteum.

12. Callus Formation 2-3 weeks  Fibro-cartilaginous callus is formed a few days after the fracture Capillaries grow into the tissue and phagocyte cells begin cleaning debris Connecting bridge across a bone fracture during repair.

13. Day 14 -Calcification of cartilage. callus and periosteal bone formation

14. CONSOLIDATION-[3-6weeks]   New bone trabeculae appear in the fibro-cartilaginous callus, which then converts into a bony callus. This occurs 3-6 weeks after injury and continues until firm union is formed 2-3 months later.

15. Day 21 - Most of the callus is composed of calcified cartilage

16. Remodelling[8-2yrs] Bone remodeling is a lifelong process where mature bone tissue is removed and new bone tissue is formed. Reshaping Or Replacement of bone following injuries. 4 phase -Bone remodeling: Activation, Resorption , Reversal formation Quiescence.

17. Days 28-35 after fracture. Calcified cartilage and newly formed bone

18. Complications of fracture healing Delayed union: Healing of bone does not take place in normal rates. Inadequate blood supply Several soft tissue damage Infection Insufficient splintage Excessive traction

19. Medicolegal importance

20. Grievious hurt 320 ipc Establising the mode of injury by analysing type of fracture Differentiate antemorterm and post-mortem fracture Age of fracture Medical negligence Battered baby syndrome Puppe’s rule

21. Grievious hurt : -320 IPC Fracture or dislocation of a bone or teeth. Mode of injury: Fall from height- thoracic and lumbar fracture ,ring fracture and comminuted fracture are common RTA- shaft fractures more common Judicial hanging C1-C2 fracture common Old age- neck of femur fracture common

22. Features Antemorterm Postmorterm Effusion of blood Present Absent Muscles around fracture Lacerated ,edematous,contused Not so Signs of healing Present Absent Histology Active cellular infiltration Not so Sequelae Fat embolism Not so

23. Age of skull fractures Healing of skull fractures Time since injury Edges of fissures stick together 1weeks Edges slightly eroded ,inner table of skull shows pitting 2weeks Edges become smooth ,bands of osseous tissue formed 3-5weeks Complete healing occurs 3months

24. Radiological changes-Features Time since injury wks Rounded fracture margin 1 Subperiosteal new bone formation Less than 2 Soft callus 2 Calcified callus 4 Fracture margin resorption 4-6 Sclerosis 4-6 Bridging – partial 8 Decrease in fracture gap 8 Bridging -complete 10 Density of callus equal to surrounding compact bone 10 New bone formation incorporate into cortex 10 Remodelling 12 Radiological changes observed in healing

25. Battered baby syndrome : Non accidental injury Direct beating -Skull fractures – occipito-parietal region, Long bones- transverse and spiral fracture common Traction lesions- periosteal hematomas, epiphyseal separation,avulsion of metaphysis . Anteroposterior and side to side compression of chest Rib fractures-NOBBING FRACTURE Delay in seeking treatment Can able to different stages of healing Autopsy-old fractures,epiphseal and metaphyseal injury (stages of healing)

26. C.P.Sreekumar M.S (Ortho) vs S.Ramanujam on 1 May, 2009 Supreme Court Of India A CASE OF NEGLIGENCE  A hairline fracture developed into displaced fracture due to wrong handling in the hospital Performed a hemiarthroplasty on a young patient of 42 years without consideration open reduction and internal fixation and against established medical practices The post-operative infection was not properly treated with the result that prosthesis got loosened within a period of two months. Compensation of rs.3 lac fine.

27. Madras High Court A. Narayanan vs Dr .Saravanan on 24 February, 2020 Condition did not improve and the swelling on his lower jaw increased. He suffered a fracture in his lower jaw.  Broken stitching needle was embedded in his lower jaw during the suturing procedure.  The x-ray revealed the presence of the broken needle in the petitioner's lower jaw.  Liable to compensate him for their negligence in performing the surgery which resulted in a needle being broken and embedded in his jaw He is suffering great hardship and undergoing psychological trauma. Grant compensation and awarded a sum of rs.10,00,000/- as compensation on account of medical negligence .

28. Used to determine sequence of shots ,blunt trauma or glass window shots. Principle: Bullet will cause fracture line to radiate from hole it causes. The fracture line emanating from second bullet hole will stop at the line of first hole. Fracture line emanating from third bullet will stop at the line caused by first and second. Also applicable to blunt force caused by any objects,like iron rod,etc Also applicable to other flat bones- Sternum and hip bone Also determine sequence of shots in glass window or similar objects

29. references The essential of forensic medicine and toxicology.K.S.Narayana reddy Textbook of forensic medicine and toxicology – anil agarwal The essential orthopedics J.maheswari A Qualitative Analysis for Sex Determination in Humans The science of fracture healing thomas A. Einhorn ,  determination of medicolegal significance from suspected osseous and dental remains J orthop trauma • volume 19, number 10 supplement, november / december 2005 Maria L. Hillier,1 M.Sc. and Lynne S. Bell,2 Ph.D. Differentiating Human Bone from Animal Bone: A Review of Histological Methods.J of forensic science Journal of Evolution of Medical and Dental Sciences/ Volume 2/ Issue 23/ June 10, 2013 Slice and algee-hewitt . modeling bone surface morphology for age estimation 837 Some Medico-Legal Aspects of the Fracture of Bone Sir Lenthal Cheatle ,