eChapters

Introduction

Nitrogen constitutes 78% of the atmospheric gases and there is about 75,000 Mg N on each hectare of land. However, 99% of the atmospheric N is as N₂ and is inert and non-reactive, while the rest 1% or even less is the reactive-N. Reactive-N is linked with H, O and C and is responsible for the creation and sustenance of all life on the planet Earth. Nitrogen is the key nutrient that separates proteins from carbohydrates and fats, the three major macronutrients for humans. As a component of proteins, N is present in DNA and RNA, which carry the hereditary characters and then as the major constitute of the body muscles of humans (and animals). Plant growth and crop production are also very much dependent on the adequate availability of N in soil.

SOIL WATER

Soil water and oxygen share the pore space in soil and generally the oxygen content is determined by the water content, which is added by irrigation or rains and then keeps on changing due to evapotranspiration. Water is the vehicle by which most nutrients move from the soil to root surface. But for the lowland rice, nutrients are most available to plants at ?eld capacity moisture (about 0.3 atmosphere soil water tension) and the availability decreases as the moisture content decreases to wilting point (about 15 atmosphere tension). That is why rainwater or irrigation increases nutrient availability, while extremely dry condition decreases it. There is thus a signi?cant interaction between water and nutrient availability in soil (Singh et al., 2014). In a study in India (Singh et al., 1980) the yield of wheat was signi?cantly affected by irrigation water and nitrogen treatments; maximum yield was obtained with irrigation at 50% available soil water in 60 cm soil depth and 120 kg ha ^–1 nitrogen addition. A study on wheat at Delhi (Kumar et al., 2015) very well shows the effect of irrigation water on yield and uptake of nutrients (NPK) (Table 5.1).

German chemist Justus Freiherr von Liebig (1803–1873), Professor at the University of Geissen and the French chemist Jean-Baptiste Joseph Dieudonne’ Boussingault (1801–1887), Professor at the University of Lyon and later Chair, Conservatoires des Artes et Matier in Paris are to be credited for analyzing the plants and coming with the idea that plants absorbed nitrogen and other mineral nutrients from the soil for their growth. D.I. Arnon and P.R. Stout, Plant Physiologists and Plant nutritionists at the University of California, Berkeley, USA, grew plants by hydroponics using pure chemical compounds and established following 3 criteria for the essentiality of nutrients for plant growth

All life on planet Earth is carbon centered; hereditary characters are controlled by DNA and RNA, growth by proteins and activities by energy from carbohydrates and fats – all these are carbon compounds. Not only this, but the life also ends as carbon compounds CO₂ or CH₄, depending on aerobic or anaerobic decomposition. Incidentally soil fertility also depends very much on soil organic carbon (SOC). In ancient days, farmers used to apply manure to maintain soil fertility and even now, urea, the nitrogen fertilizer used in the largest amounts, is a carbon compound. All living forms on the Earth including all plant and animal species and their activities are a part of global carbon cycle. The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the earth.

INTRODUCTION

In biology, fertility is de?ned as capacity to produce off-springs; however, in Soil Science a ?ne difference is made between a fertile and a productive soil. Soil Productivity is the ability of a soil to produce a crop using the entire spectrum of its physical, chemical and biological attributes, while Soil Fertility refers to the capacity of a soil to supply all essential plant nutrients in the desired amounts. Thus, soil fertility management is basically the nutrient management. To put it in simple words, a productive soil is always fertile, while a fertile soil may not be productive for a variety of factors, such as lack of adequate moisture in drier regions or lack of adequate air due to water-logging for most upland crops. Of late, a term ‘ Soil Health’ has been introduced. Soil Health is an assemblage of chemical, physical and biological parameters that closely relate to native or acquired production capacity and sustenance of ecologically important regulatory role (Katyal et al., 2016). It is measured against prede?ned parameters of soil’s status of fertility, compact ability, erodibility and biology. This again tends to relate soil fertility to nutrient content, availability and management.

LAND VERSUS SOIL

Land is a part of Earth’s surface that is not covered by water. It is used for agriculture, building houses, of?ce buildings, schools, hospitals, roads, railroads and even water canals. Land is measured by area [length (l) × width (w)] and the units are square meters (m²), square centimeters (cm²) etc. On the other hand, soil is Earth’s crust, which could vary from a few centimeters to a few meters in thickness (depth), needs a measure of volume [length (l) × width (w) × depth (d)] and the units are cubic meters (m³), cubic centimeters (cm³) etc. Soil is thus a three-dimensional natural body on Earth’s surface that provides anchorage to growing plants/ trees and shelter to soil biota and is responsible for the storage of water and plant nutrients, which are essential for crop production. In addition, it helps in the biodegradation of soil pollutants and puri?cation of ground water, the major source of drinking water in the world. Soil feeds all living beings on Earth and its degradation is one of the reasons for inadequate human nutrition

Physiotherapy may be defined as the use of physical techniques like massage, exercise, heat, cold, sound waves, electric current etc for the treatment of injuries and movement dysfunction. Physiotherapy deals with the treatment of diseases by physical methods. It is used for treating injuries, strain, spasm, painful conditions, sprain of tendons, paralysis, postoperative trauma etc. It improves functioning of nerve, muscles and bones. The aim of physical therapy is the restoration of function and promotion of tissue healing by assisting normal physiological processes. The physiological response to physical therapy is its effect on the vascular supply; this in turn reproduces similar changes in deeper tissues.

Bone grafting is important in the treatment of non-unions, delayed unions, joint arthrodesis, and filling of bone cavities and the replacement of bone lost due to cyst, trauma or tumours. An ideal bone graft or substitutes should be a material that is biologically inert or bioadaptable, a source of osteogenesis, having osteoconductive property, act as a mechanical support, readily available, easily adaptable to the site in term of shape and size and replaceable by the host bone. The beneficial effect upon osteogenesis of impregnating allograft bone with autogenous red marrow or autogenous citrated plasma has been the subject of current research. It is claimed that autogenous fresh bone marrow and citrated plasma are two useful contributors for osteogenesis. Biodegradable and bioadaptable ceramics like ALCAP (Aluminum-calcium-phosphorus oxide) seem to be the most promising biomaterials for correcting bone defects, since these ceramics encourage self-replacement by endogenous bone. However, use of bone grafts and ceramics with autogenous bone marrow or citrated plasma has not been investigated so far. This chapter is undertaken to evaluate bone marrow and plasma impregnated bone allografts and ceramic implants in fracture healing in goats.

Study protocol & grouping

Eighteen, locally available nondescript male/female goats of 12-14 months of age are selected on the basis of their clinical status and are kept under observation for a period of one month before start of experiment. The animals are housed in their shed and are allowed to graze in the surrounding pasture. They are kept on standard feed and fodder throughout the experiment. The animals are randomly divided into six groups consisting of three animals each. Two trials of a similar experiment are performed in each goat. A total of 36 trials are conducted to evaluate different bone grafts and ceramic implants (six trials for each group with three animals each): Group A, frozen decalcified allogenic bone grafts; Group B, frozen decalcified allograft impregnated with autogenous bone marrow (composite bone graft); Group C, frozen decalcified allograft impregnated with autogenous citrated plasma (composite bone graft); Group D, ALCAP ceramics; Group E, ALCAP ceramics impregnated with autogenous bone marrow; Group F, ALCAP ceramics impregnated with autogenous citrated plasma.

Healing of fracture is a consequence of cellular behaviour in a living organism and as such can be modified by almost all endogenous or exogenous factors that affect the metabolic function of cells. These factors include transforming growth factor-β, bone morphogenetic proteins, hormones, vitamins and prostaglandins. The anabolic hormones like thyroxine and insulin accelerate bone formation in experimental animal. Hence, this chapter is proposed to evaluate the effects of thyroxine and insulin therapy in the management of tibial metaphyseal fracture in dogs.

Clinically healthy, adult mongrel dogs (15) of either sex are randomly divided into three groups (A₁, A₂ and A₃) of 5 animals each. In all the animals, unilateral metaphyseal fracture is created in the proximal tibia and then immobilized with cross intramedullary pinning with interfragmentary wiring under thiopental (5%) anaesthesia. All the animals are administered broad-spectrum antibiotic (streptopenicillin @ 1 g intramuscularly /dog/day) and analgesic (5 ml I/M daily) and surgical wounds are dressed daily with Povidone iodine and Lorexane cream for 5 days postoperatively. In group A₂, thyroxine sodium tablets (0.013 mg/kg body wt, orally) and in A₃, insulin injection (2 IU/kg body wt, s/c) are given on day 7 and then on every alternate day till day 45 postoperatively, at one specific time. Group A₁, is remained as control, in this group no hormonal therapy is given.

Craniocaudal and mediolateral radiographs of the fracture site are taken immediately after surgery and subsequent on days 15, 30, 45 and 60 postoperatively. The radiographs are observed for status of fracture reduction and fixation immediately after surgery and subsequently for the maintenance of reduction, progress of fracture healing and complication, if any, at different intervals.

Among the epiphyseal and metaphyseal fractures of the different long bones, fractures of the proximal tibia are quite commonly reported and require special attention due to their proximity to the compound stifle joint. Hence, a standard fixation technique is needed to treat such fractures, which also permit early ambulation and preserve range of joint motion in addition to providing rigid fracture fixation. Different treatment modalities have been tried for fixation of metaphyseal fractures with variable results. No single method is appropriate in all circumstances and treatment indication often overlaps. Therefore, in this present chapter, an attempt has been made to evolve a standard technique for the management of such fractures.

Ten clinically healthy mongrel dogs are maintained under uniform housing, feeding and management conditions, acclimatized, immunized against rabies, dewormed and randomly divided into two groups (A and B) of five animals each. In all the animals unilateral metaphyseal fracture is created in the proximal tibia under general anaesthesia with intravenous thiopental sodium (5%). In the animals of group A, the fracture is immobilized with cross intramedullary Steinmann pinning with interfragmentary wiring, whereas, single intramedullary pinning along with interfragmentary wiring is performed in the animals of group B. Antiseptic dressing of the wounds is done daily for 1 week with povidone-iodine. All the animals are administered Enrofloxacin at the dose rate of 5 mg/ kg b.wt intramuscularly daily for 5 days posoperatively. Skin sutures are removed on day 10 post-operation

One of the most common fractures seen in the dog is comminutuion of femoral shaft, often related to sever impact from an automobile accident or jump from a height. Comminuted fractures are characterized by one or more butterfly fragments and assorted small bone chips that are especially difficult to align accurately and stabilize completely. These complicated fractures require sophisticated repair technique that are capable to resisting compression, bending and rotational forces. Rebuilding of comminuted fractures so that all fragments are accurately aligned and gaps are eliminated is often impossible. Non-union and osteomylitis have their highest incidence in these fractures. Over the years, several techniques are tried to treat comminuted femoral fractures with different success rate and there is a lack of uniform fracture presentation. Hence, it will be difficult to compare different techniques in a particular type of fracture. The present chapter is, therefore, undertaken to evaluate radiographically and histopathologically the efficacy of three different internal fixation techniques in the management of comminuted diaphyseal femoral fracture in dogs.

Clinically healthy, adult mongrel dogs (15) of either sex are randomly divided into groups A, B and C of 5 animals each. In all the animals unilateral comminuted diaphyseal femoral fractures is created under general (thiopental - 5%) anaesthesia and is immobilized with intramedullary (IM) pinning with cerclage wiring (Gr. A), neutralization bone plating (Gr. B) and neutralization bone plating with cerclage wiring (Gr. C) respectively. All the animals are administered broad spectrum antibiotic (streptopenicillin @ I g intramuscularly (dog/day) and analgesic (diclophenac sodium @ l mg/ kg b. wt. daily) and surgical wounds are dressed daily with povidone iodine and antibiotic cream for 5 days postoperatively.

Lateral and oblique views of radiography are taken at the operated site just after the operation and subsequently on days 15, 30, 45 and 60 postoperatively. The radiographs are observed for status of fracture reduction and fixation, progress of healing at the fracture site and complications like fixation failure, osteomylitis etc., if any, at different intervals. Bone sections are collected from the fracture site including adjacent normal bone after sacrificing the animals on day 60. The sections are decalcified using Goodling and Stewart’s solution (80% distilled water, 15% formic acid and 5% formalin) and then processed routinely for H & E staining for histopathological studies

Minimally invasive percutaneous osteosynthesis (MIPO), or minimally invasive fracture repair, was introduced into human orthopedic surgery during the 1990s because of several distinct advantages over traditional open reduction techniques. In MIPO, large incisions to facilitate open reduction are avoided and implants are introduced through small stab incisions in the skin. This led to advent to more biology friendly techniques. These biological techniques lay stress upon maximal preservation of blood supply around the fractured bone by minimal direct handling of the fracture environment. MIPO offer advantages which include preservation of the fracture hematoma; less surgical trauma to the surrounding soft tissues, reduced operative time therefore, decreased risk of infection and ultimately leading to indirect bone healing with abundant callus. Minimally invasive plate osteosynthesis (MIPO) is a novel technique for application of principles of biological fracture healing with a philosophy of dealing with soft tissues with utmost respect. Following advancements in implant technology and development of techniques of indirect fracture reduction this technique gained more popularity. The evolution of MIPO began with the use of bridge plating. Initially a conventional plate is applied for comminuted femoral fractures using long incisions but with preservation of the vastus lateralis muscle resulting in healing with abundant callus. Subsequently, the size of incisions got decreased, rather two small incisions are given at proximal and distal ends and plates are bridged sub muscularly over the fracture fragments. This technique causes minimal distress to soft tissues and bone, provides access to the bone through soft tissue windows, with minimal or no contact with the fracture by indirect reduction tools and leaving behind minimal foot prints.

Standard postoperative management of animals with fractures includes the use of nonsteriodal anti-inflammatory drug (NSAID). Nonsteriodal anti-inflammatory drug inhibits inflammatory responses by blocking prostaglandin (PG) synthesis via the Cyclooxygenase pathway of arachidonic acid metabolism. However, PG is important factor in early phase of bone healing. A local increase of PG concentration is a response of bone to trauma and PG (particularly PG₂) may stimulate differentiation and proliferation of osteoprogenitor cells during early bone healing. It has been reported that NSAID, such as Diclofenac acid, ibuprofen, indomethacin, aspirin, salicylic acid decreased ingrowths of bone into porous coated implants and decreased mineral content in rabbits. In view of the above fact, this chapter is undertaken to investigate the effects of one potent NSAID (Flunixin Meglumine) on fracture healing.

The study is conducted in ten clinically healthy adult New Zealand White rabbits of either sex divided into two groups (A and B) consisting of five animals each. In all animals, mid-shaft simple transverse fracture is created in both the ulnae under thiopental (2.5%) anaesthesia. In animals of group A, 0.25ml (12.5 mg) Flunixin Meglumine (Ilium Flunixil) is injected intramuscularly on alternate days from day 5-20 postoperatively whereas, in group B no drug is given. Lateral and anterio-posterior radiographs are taken on day 0, 10, 20, 30 and 40 post-fracture. The radiographs are observed for progress of fracture healing and complication, if any, at different interval. The specimen for histopathological study is collected from the healed site of test bones immediately after euthanizing the animals on day 40. Every specimen is consisted of both healing and adjacent host bone. The bone sections are preserved in 10% formalin for 9-10 days and then are decalcified using Goodling and Stewart’s solution (15% formic acid, 5% formalin and 80% distilled water). Completely decalcified sections are then processed routinely for H&E staining. These sections are observed for the status of healing at the fracture site, at cellular level.

Bone healing can be modified by variety of endogenous or exogenous factors that affect the metabolic function of bone cells. The Food and Drug Administration is approved the use of low-intensity ultrasound for the accelerated healing of fresh fractures in October 1994 and for the treatment of established nonunion in February 2002. The first regulatory approval is based primarily upon two rigorous, double - blind, placebo controlled clinical trials, which shows that the rate of healing of fresh fracture is accelerated by treatment with ultrasound. Therapeutic ultrasound has been able to improve functional activity, reduce post-ambulatory period, alleviate suffering and restore the animal’s health early. It has been used frequently for acceleration of healing in various musculotendinous injuries in animal. However, the role of ultrasound therapy in different dose levels in fracture healing has not been elucidated properly. In view of the above fact, this chapter is undertaken to investigate the effects of therapeutic ultrasound in two different doses, on cortical bone healing in rabbits.

Twelve clinically healthy adult New Zealand white rabbits of either sex are divided equally into three groups A, B and C, and kept on standard diet and uniform management. In all animals, mid-shaft simple transverse fracture is created in both the ulnae under thiopental (2.5%) anaesthesia. All the animals are administered broad-spectrum antibiotic and analgesic and surgical wounds are dressed daily with povidone iodine and antibiotic cream for 4 days postoperatively. Group A animal is received pulsed ultrasound therapy @ lW/ cm² (1:1) whereas, group C animals is received continuous ultrasound therapy @ 3 W/cm², starting on day 4 after the creation of fracture. Ten treatments, each consisting of 5 min duration, are given on alternate days. Group B animals are served as control. In both the test groups (A and C), the transducer head of the ultrasound machine is moved in a linear fashion along the length of the bone after applying ultrasound gel.

The action of the sex hormone is not confined to the growth and development of the sex organ alone, but the normal body growth as well as the growth of the skeleton are to a great extent influenced by these hormones. It is well documented that following oopherectomy, female experience a “rapid phase” of bone loss for the next few years. Of the female gonadial hormones, the action of estrogen on skeletal growth has been studies by various workers and shows that estrogen replacement therapy can help to prevent the postmenopausal stage of accelerated rate of bone loss. The effects of progesterone on bone healing or bone growth has not yet been studies in detail. The objective in this chapter is thus undertaken to investigate the effects of progesterone supplement on cortical bone healing in spayed rabbits.

The study is conducted on ten clinically healthy female adult New Zealand White rabbits divided into two equal groups (A and B) consisting of five animals each. All animals are spayed and kept in standard diet and management throughout the experiment. In all animals, midshaft simple transverse fractures are created in both the ulnae under thiopental (2.5%) anaesthesia. In test group (gr A), 1mg (=1ml) of progesterone is injected subcutaneously in alternate days for upto 35 post fracture days. Lateral and anterio-posterior radiographs are taken on days 0, 7, 14, 21, 28 and 35 post-fracture. These radiographs are observed for progress of fracture healing and complications, if any, at different intervals.

Bone being a dynamic tissue undergoing constant biological changes, organic and mineral phases of fracture healing need an optimum general body metabolism and even a slight deviation from normal condition of the body is likely to cause considerable alterations in the healing process. Facture healing can be modified by variety of endogenous or exogenous factors that affect the metabolic function of cells. These factors include transforming growth factor beta, bone morphogenetic proteins, hormones, vitamins and prostaglandins. Anabolic steroids have the property of preventing the destruction and elimination of nitrogenous substances and minerals from the body. They help, thus, to have a positive nitrogen and mineral balance which is essential for healing and regeneration of any kind of tissue in a living organism. This chapter is undertaken to observe the effect of anabolic steroid (Durabolin) on fracture healing.

This study is conducted on ten clinically healthy adult New Zealand White rabbits of either sex divided into two equal groups (X and Z) consisting five animals each. All the animals are kept in standard diet and management throughout the experiment. In all animals, midshaft segmental defect (1cm) are created in both the ulnae under thiopental (2.5%) anaesthesia. In test group (Gr X), 10mg of Nandrolone phenyl propionate (durabolin) is injected intramuscularly in 5 days interval at 7 occasions. Lateral and anterio-posterior radiographs are taken on days 0, 7, 14, 21, 28 and 35 postoperative days. The radiographs are observed for progress of fracture healing and complications, if any, at different intervals.

Inflammation at the fracture site is increased upto 4^th postoperative days in all the animals of both groups, and then the limb is normal in appearance by day 7. Surgical wound healing is by first intention in all the animals. Earliest return of weight bearing is seen in animals of test group followed by control. Body weight and food intake are increased two-fold in the test group of animals.

India is bestowed with an enormous wealth of medicinal plants and has a rich heritage of treating human and animal ailments by using herbal medicines. However, there is need for a systemic, scientific approach to validate the authenticity of claims on plant-based medicaments. This approach has paid rich dividends in developing cheaper, safer, effective and eco-friendly remedies, which recently has gained worldwide attention. Cissus quadrangularis, Linn (Syn. Vitis quadrangularis, Wall; Heliotropium indicum, Linn) is a tender climber with fleshy quadrangular stems and grows in the hotter parts of Indian subcontinent, Sri Lanka and East Africa. In Hindi it is known as hardjore; in English as adamant creeper, bonesetter; in Ceylon as hiressa; in China as di xanh voung; in Burma as shazam-lese and in Bangladesh as harbhanga. Considering the advantage of herbal medicines, it is planned in this chapter to investigate the efficacy of Cissus quadrangularis, Linn, in one of the most commonly encountered problem of fractures in small animals.

Dried ethanolic extract of Cissus quadrangularis (CQ) is obtained from 500g of dried finely powered stems using soxhlet apparatus. It is dissolved in a vanishing base to make a semi-solid paste for local application. For parental use, this extract is reconstituted with distilled water (100 mg/ml) and filtered.

Twelve clinically healthy mongrel adult dogs aged 2-3 years and weighing 10-15 kg is randomly divided into two equal groups (A and B). In all animals operative site is prepared for aseptic surgery. Premedication is done with atropine sulphate @ 0.06 mg/ kg body weight subcutaneously and anaesthesia is achieved with a combination of Xylazine hydrochloride @ 1 mg/kg body wt. and Ketamine hydrochloride @ 10 mg/kg body wt. intravenously. Unilateral comminuted diaphyseal femoral osteotomy is created under general anaesthesia and the bone defect is immobilized with neutralization bone plating (AO/ASIF technique). All the animals are administered 5 mg/kg b wt Enrofloxacin intramuscularly for 5 d and 1 mg/ kg b wt Diclofenac sodium injection intramuscularly for 5 d postoperatively. Skin sutures are removed after 10 days. In the animals of group B, in addition to the postoperative treatment, the ethanolic extract of the herb, Cissus quadrangularis is applied on the skin twice daily along with subcutaneous injection (50 mg/ kg body wt.) on every alternate day for 20 d postoperatively.

The action of the gonadial hormone is not confined to the growth and development of the sexual organs alone, but the normal body growth as well as the growth of the skeleton are to a great extent influenced by these hormones. Of the female gonadial hormones, the action of estrogen and progesterone on skeletal growth has not been studied in detail. Some reports implicate estrogen deficiency in post menopausal osteoporosis and shows that estrogen replacement therapy can help to prevent that post menopausal stage of accelerated rate of bone loss. It’s reported that the progesterone treatment play a significant role in regulating cortical bone cell activity and as such, suggest that progesterone may play a part in the prevention and slowing down of cortical bone loss in females following menopause or oophorectomy. The effect of gonadotropic hormone on bone healing has not yet been studied in detail. The chapter is thus, undertaken to investigate the effects of gonadotropic hormone (Gn-rh)) on cortical bone healing in female rabbits.

Clinically healthy adult female New Zealand white rabbits (10) are divided equally into groups A and B each consisting of 5 animals. All animals are kept on standard diet and management throughout the experiment. In all animals midshafts simple transverse fracture is created in both the ulnae under thiopental (2.5%) anesthesia. In test group (group A) 0.1 ml of Gn-rh analogue is injected intramuscularly at 3 days interval up to 30 days post operatively.

Lateral and anterio-posterior radiographs are taken on days 0, 10, 20. 30. and 40-post fracture. These radiographs are observed for progress of fracture healing and complication, if any, at different intervals. The specimens for histopathological study are collected from the healed site of test bone immediately after euthanizing the animals on day 40. Every specimen consists of better healing site and adjacent host bone. The bone sections are preserved in 10% formalin for 9 to 10 days and then are decalcified using Goodling and Stewart’s solution (15% formic acid, 5% formalin and 80% distilled water). Completely decalcified bone sections are then processed routinely for H & E staining. These sections are observed for status of healing at fracture site.

Bone healing is an extraordinary process involving not only an inflammatory reaction and formation of callus but also reconstruction of the defect to regain its original biomechanical strength. Bone healing can be modified by variety of endogenous or exogenous factors that affect the metabolic function of bone cells. Prostaglandins (PG), a family of cycled derivation of unsaturated long chain fatty acids, are intimately associated with bone metabolism, and are important as locally active agents with significant effects on bone and bone cells in vitro. In some experimental studies, it is suggested that the local increase of prostaglandin in response to trauma may act to stimulate differentiation and proliferation of osteoprogenitor cells during fracture healing, whereas, specific prostaglandin antagonists, indomethacin, inhibited fracture healing. The objective of this chapter is to investigate the effects of locally (defect-site) administered prostaglandin (PGE₂) on cortical bone healing in rabbit model.

Clinically healthy adult New Zealand White rabbits (10) of either sex are divided equally into groups A and B, consisting of 5 animals each. They are kept on standard diet and management throughout the experiment. In all the animals, mid-shaft single transverse fracture is created in both the ulnae under thiopental (2.5%) anaesthesia.

In test group A, 0.1 ml (25 µg) prostaglandin (PGE₂) is injected at fracture site on alternate day for 30 post operative days, whereas, group B is served as control. In both the groups lateral and antero-posterior radiographs are taken on days 0, 10, 20, 30 and 40 postoperatively to observe progress of fracture healing and complication, if any at different intervals.

During orthopaedic surgery, it is very difficult and sometimes impossible to stop the flow of blood from fractured bone. For this reason, there has been a longstanding interest in haemostatic agent for osseous tissue surgery. Bone –wax, oxidized cellulose, sanguistat, bone dust, marrow paste and combination using polyethylene glycols have been tried for osseous hemostasis, however, bone wax appears to be the most promising bone haemostatic agent and is widely used today. But, very littlie work has been done to define the local effect of bone wax on healing and osteogenesis and its eventual fate in animals.

The objective of this study is thus, undertaken in this chapter to investigate the effects of bone wax on cortical bone healing.

Clinically healthy adult New Zealand white rabbits (10) of either sex are divided equally in to two groups A and B, consisting of 5 animals each. All animals are kept in standard diet and management throughout the experiment. In all animals’ mid-shaft simple transverse fracture are created in both the ulnae under Xylazine-Ketamine anaesthesia. In animals of group A, bone wax packed in between two fracture ends, whereas, in animals of group B, fracture site kept as it is.

Lateral and anterio-posterior radiographs are taken on days 0, 10, 20, 30 and 40 post-fracture. The radiographs are observed for progress of fracture healing and complication, if any at different interval. The specimens for histopathological study are collected from the healed site of test bone immediately after euthanizing the animals on day 40. Every specimen is consisted of both healing site and adjacent host bone. The bone sections are preserved in 10% formalin for 9-10 days and then are decalcified using Goodling and Stewart’s solution (15% formic acid, 5% formalin and 80% distilled water). Completely decalcified bone sections are then processed routinely for H&E staining. These sections are observed for the status of healing at the fracture site at cellular level.