2/23/2014 The Healing Process & Guidelines for Using Therapeutic Modalities Lecture 02 – Part I RHS 325 Electrotherapy – Lecture 02 Slide # 1 Objectives Define inflammation and its associated signs and symptoms. Clarify how therapeutic modalities should be used in rehabilitation of various conditions. Compare the physiologic events associated with the three phases of the healing process. Formulate a plan for how specific modalities can be used effectively during each phase of healing and provide a rationale for their use. Categorize the indications and contraindications for using the various modalities discussed throughout this course. RHS 325 Electrotherapy – Lecture 02 Slide # 2 1 2/23/2014 Understanding the Healing Process Clinical decisions on how and when therapeutic modalities may best be used should be based on recognition of signs and symptoms as well as some awareness of the time frames associated with the various phases of the healing process. Basically, the healing process consists of 1. Inflammatory response phase 2. Fibroblastic-repair phase 3. Maturation-remodeling phase RHS 325 Electrotherapy – Lecture 02 Slide # 3 Understanding the Healing Process … cont. Inflammatory response phase Inflammation is the body's attempt at self-protection; the aim being to remove harmful stimuli, including damaged cells, irritants, or pathogens - and begin the healing process Signs of Inflammation Redness Swelling Tenderness to touch Increased temperature RHS 325 Electrotherapy – Lecture 02 Slide # 4 2 2/23/2014 Understanding the Healing Process … cont. Inflammatory response phase … cont. • Cellular Response Leukocytes and other phagocytic cells and exudate are delivered to the injured tissue. • Vascular Response It involves vascular spasm, formation of a platelet plug, blood coagulation, and growth of fibrous tissue. The immediate response to damage is a vasoconstriction of the vascular walls that lasts for approximately 5 to 10 minutes. RHS 325 Electrotherapy – Lecture 02 Slide # 5 Understanding the Healing Process … cont. Inflammatory response phase … cont. • Chemical Mediators Three chemical mediators, histamine, leucotaxin, and necrosin, are important in limiting the amount of exudate and swelling following injury. Histamine released from the injured mast cells causes vasodilation and increased cell permeability, owing to swelling of endothelial cells, and then separation between the cells. Leucotaxin is responsible for margination in which leukocytes line up along the cell walls. It also increases cell permeability locally, thus affecting passage of the fluid and white blood cells through cell walls by diapedesis to form exudate. o Therefore, vasodilation and active hyperemia are important in exudate (plasma) formation and supplying leukocytes to the injured area. Necrosin is responsible for phagocytic activity. The amount of swelling that occurs is directly related to the extent of vessel damage. RHS 325 Electrotherapy – Lecture 02 Slide # 6 3 2/23/2014 Understanding the Healing Process … cont. Inflammatory response phase … cont. • Function of Platelets Platelets do not normally adhere to the vascular wall. However, injury to a vessel disrupts the endothelium and exposes the collagen fibers. Platelets adhere to the collagen fibers to create a sticky matrix on the vascular wall, to which additional platelets and leukocytes adhere and eventually form a plug. These plugs obstruct local lymphatic fluid drainage and thus localize the injury response. RHS 325 Electrotherapy – Lecture 02 Slide # 7 Understanding the Healing Process … cont. Inflammatory response phase … cont. • Clot Formation Damage cell Thromboplastin (Protein) cause conversion Thrombine supply to the injured area. Prothrombine Cahnged fibrinogen into very sticky fibrin clot that shuts off blood Clot formation begins around 12 hours following injury and is completed by 48 hours. As a result of a combination of these factors, the injured area becomes walled off during the inflammatory stage of healing. The leukocytes phagocytize most of the foreign debris toward the end of the inflamatory phase, setting the stage for the fibroblastic phase. This initial inflammatory response lasts for approximately 2 to 4 days following initial injury. RHS 325 Electrotherapy – Lecture 02 Slide # 8 4 2/23/2014 RHS 325 Electrotherapy – Lecture 02 Slide # 9 Understanding the Healing Process … cont. Inflammatory response phase … cont. Chronic Inflammation??? Home work RHS 325 Electrotherapy – Lecture 02 Slide # 10 5 2/23/2014 Understanding the Healing Process … cont. Fibroblastic –Repair Phase During the fibroblastic phase of healing, proliferative and regenerative activity leading to scar formation and repair of the injured tissue. The period of scar formation referred to as fibroplasia begins within the first few hours following injury and may last for as long as 4 to 6 weeks. The patient may still indicate some tenderness to touch and will usually complain of pain when particular movements stress the injured structure. As scar formation progresses, complaints of tenderness or pain gradually disappear RHS 325 Electrotherapy – Lecture 02 Slide # 11 Understanding the Healing Process … cont. Fibroblastic –Repair Phase … cont. The formation of a delicate connective tissue called granulation tissue occurs with the breakdown of the fibrin clot. Granulation tissue consists of fibroblasts, collagen, and capillaries. It appears as a reddish granular mass of connective tissue that fills in the gaps during the healing process. Fibroblastic cells begin to synthesize an extracellular matrix that contains protein fibers of collagen & elastin,a ground substance RHS 325 Electrotherapy – Lecture 02 Slide # 12 6 2/23/2014 Understanding the Healing Process … cont. Fibroblastic –Repair Phase … cont. On about day 6 or 7, fibroblasts also begin producing collagen fibers that are deposited in a random fashion throughout the forming scar. As the collagen continues to proliferate, the tensile strength of the wound rapidly increases in proportion to the rate of collagen synthesis. As the tensile strength increases, the number of fibroblasts diminishes to signal the beginning of the maturation phase. RHS 325 Electrotherapy – Lecture 02 Slide # 13 Understanding the Healing Process … cont. Fibroblastic –Repair Phase … cont. This normal sequence of events in the repair phase leads to the formation of minimal scar tissue. Occasionally, a persistent inflammatory response and continued release of inflammatory products can promote extended fibroplasia and excessive fibrogenesis that can lead to irreversible tissue damage. Fibrosis can occur in synovial structures, as is the case with adhesive capsulitis in the shoulder; in extraarticular articular tissues including tendons and ligaments; in bursa; or in muscle. RHS 325 Electrotherapy – Lecture 02 Slide # 14 7 2/23/2014 RHS 325 Electrotherapy – Lecture 02 Slide # 15 Understanding the Healing Process … cont. Maturation – Remodeling Phase The maturation-remodeling phase of healing is a long-term process o The maturation phase of healing may require several years to be totally complete. This phase features a realignment or remodeling of the collagen fibers that make up the scar tissue according to the tensile forces to which that scar is subjected. RHS 325 Electrotherapy – Lecture 02 Slide # 16 8 2/23/2014 RHS 325 Electrotherapy – Lecture 02 Slide # 17 RHS 325 Electrotherapy – Lecture 02 Slide # 18 9