Occupational Therapy- Biomechanical dysfunction and analysis

Occupational Therapy- Biomechanical component * Biomechanical dysfunction and analysis

1. Occupational Therapy Biomechanical Dysfunction and Analysis

2. Biomechanical Component Assessment of biomechanical component area carried out to determine : -Limitations impacting on performance -How much improvement is required to enable adequate function -Where to focus treatment - Joints, muscles, endurance -Most appropriate treatment approach -Effectiveness of treatment Evaluation of treatment important for: -Psychological impact on client -OT & other team members -Medico-legal reasons

3. ROM through which a joint can be moved Range of motion (or ROM), is the linear or angular distance that a moving object may normally travel while properly attached to another Passive ROM = moved by outside force e.g . therapist Only assess actual ROM of joint Active ROM = moved by muscle power -Assess both range & muscle power -Unable to identify if ROM, power, or both are affected

4. Muscle Strength M uscular strength is the amount of force a muscle can produce in a single effort. Muscle strength is affected by cells and nerves. Amount of force exerted by one or group of muscles in single voluntary contraction. Force depends on: Recruitment of muscle fibres Mechanical advantage of lever system Neuromuscular aspects Motivation When grading strength , consider moving against gravity or with gravity eliminated

5. Endurance T he ability of an organism to exert itself and remain active for a long period of time, as well as its ability to resist, withstand, recover from, and have immunity to trauma, wounds, or fatigue. Cardiorespiratory Recognized externally by pulse & breathing Increase in vital signs indicates increasing amount of work performed by cardiorespiratory system Increase in heart rate, blood pressure & breathing rate corresponds with increase in workload Can be assessed by monitoring vital signs & symptoms, & using subjective measures (e.g. perceived exertion). Muscular Repetition of submaximal contractions (isotonic) or submaximal holding (isometric)

6. Mechanisms involved in contracture & deformity development A muscle contracture is a permanent shortening of a muscle or joint. It is usually in response to prolonged hypertonic spasticity in a concentrated muscle area, such as is seen in the tightest muscles of people with conditions like spastic cerebral palsy. Immobility Chronic odema Scarring following wound healing Muscle imbalance e.g. hypertonicity Weakness Pain Disuse osteoporosis Inflammation e.g. RA, sepsis Degenerative processes e.g. OA Congenital disorders

7. Clinical manifestations of prolonged immobility Muscular Decreased strength Decreased endurance Muscle atrophy Begins after 1-3 days Impaired task precision Poor coordination Skeletal - Osteoporosis - Joint fibrosis & ankylosis Begins in 1-2 mths

8. Clinical manifestations of prolonged immobility Deconditioning can start to occur after as little as two days of being in bed, and 'side effects' of prolonged immobility occur in up to 40% of elderly hospitalized people. Symptoms of deconditioning include: fatigue, falls and poor coping with the activities of daily living. Cardiorespiratory Increased heart rate Decreased cardiac output Orthostatic hypotension Decreased vital capacity Psychological Depression Apathy Intellectual dulling

9. E dema a condition characterized by an excess of watery fluid collecting in the cavities or tissues of the body Occurs following injury when interstitial fluid leaks into injured or inflamed site In early stages is reversible In chronic edema, protein rich fluid becomes fibrotic & creates adhesion between collagen structures

10. What is fluid retention? Fluid retention is also called edema or water retention. It occurs when parts of the body swell due to the build-up of trapped fluid. You may have fluid retention if you have: swelling or puffiness under the skin skin that looks or feels tight or shiny skin that indents when pressed, or does not bounce back after being pressed for a few seconds discolored skin aching limbs or joints weight gain a noticeable increase in size of your abdomen

11. What causes fluid retention? Some people get fluid retention due to illnesses like: - heart conditions such as heart failure or cardiomyopathy - chronic lung disease - thyroid problems - malnutrition - kidney failure, cirrhosis of the liver or an underactive thyroid Certain medications cause fluid retention, such as: - some antidepressants - some heart and blood pressure medicines - corticosteroids - the pill - non-steroidal anti-inflammatory drugs (NSAIDs) -some hormone replacement therapies

12. What causes fluid retention? A problem in one part of your arm or leg can cause fluid retention further down your arm or leg, if you have: - a problem with your lymphatic system, which drains fluid from tissues - a vein condition, such as deep vein thrombosis - the build-up of fat, usually in the legs - a burn or other type of injury You can also get fluid retention if you are pregnant, overweight or malnourished.

13. Wound healing Wound healing is a natural restorative response to tissue injury. Healing is the interaction of a complex cascade of cellular events that generates resurfacing, reconstitution, and restoration of the tensile strength of injured skin. Phases of wound healing: - Hemostasis & Inflammation - Proliferation & Fibroplasia - Scar maturation/ Remodeling - Wound contracture .

14. Hemostasis Phase Hemostasis is the process of the wound being closed by clotting. Hemostasis starts when blood leaks out of the body. The first step of hemostasis is when blood vessels constrict to restrict the blood flow. Next, platelets stick together in order to seal the break in the wall of the blood vessel. Finally, coagulation occurs and reinforces the platelet plug with threads of fibrin which are like a molecular binding agent.

15. - The hemostasis stage of wound healing happens very quickly. The platelets adhere to the sub-endothelium surface within seconds of the rupture of a blood vessel's epithelial wall. After that, the first fibrin strands begin to adhere in about sixty seconds. As the fibrin mesh begins, the blood is transformed from liquid to gel through pro-coagulants and the release of prothrombin. The formation of a thrombus or clot keeps the platelets and blood cells trapped in the wound area. The thrombus is generally important in the stages of wound healing but becomes a problem if it detaches from the vessel wall and goes through the circulatory system, possibly causing a stroke, pulmonary embolism or heart attack.

16. Inflammatory Phase Inflammation is the second stage of wound healing and begins right after the injury when the injured blood vessels leak transudate (made of water, salt, and protein) causing localized swelling. Inflammation both controls bleeding and prevents infection. The fluid engorgement allows healing and repair cells to move to the site of the wound. During the inflammatory phase, damaged cells, pathogens, and bacteria are removed from the wound area. These white blood cells, growth factors, nutrients and enzymes create the swelling, heat, pain and redness commonly seen during this stage of wound healing. Inflammation is a natural part of the wound healing process and only problematic if prolonged or excessive..

17. Proliferative Phase The proliferative phase of wound healing is when the wound is rebuilt with new tissue made up of collagen and extracellular matrix. In the proliferative phase, the wound contracts as new tissues are built. In addition, a new network of blood vessels must be constructed so that the granulation tissue can be healthy and receive sufficient oxygen and nutrients. Myo -fibroblasts cause the wound to contract by gripping the wound edges and pulling them together using a mechanism similar to that of smooth muscle cells. In healthy stages of wound healing, granulation tissue is pink or red and uneven in texture. Moreover, healthy granulation tissue does not bleed easily

18. Proliferative Phase Dark granulation tissue can be a sign of infection, ischemia, or poor perfusion. In the final phase of the proliferative stage of wound healing, epithelial cells resurface the injury. It is important to remember that epithelialization happens faster when wounds are kept moist and hydrated. Generally, when occlusive or semi-occlusive dressings are applied within 48 hours after injury, they will maintain correct tissue humidity to optimize epithelialization.

19. Maturation Phase Also called the remodeling stage of wound healing, the maturation phase is when collagen is remodeled from type III to type I and the wound fully closes. The cells that had been used to repair the wound but which are no longer needed are removed by apoptosis, or programmed cell death When collagen is laid down during the proliferative phase, it is disorganized and the wound is thick. During the maturation phase, collagen is aligned along tension lines and water is reabsorbed so the collagen fibers can lie closer together and cross-link.

20. Maturation Phase Cross-linking of collagen reduces scar thickness and also makes the skin area of the wound stronger. Generally, remodeling begins about 21 days after an injury and can continue for a year or more. Even with cross-linking, healed wound areas continue to be weaker than uninjured skin, generally only having 80% of the tensile strength of unwounded skin. The stages of wound healing are a complex and fragile process. Failure to progress in the stages of wound healing can lead to chronic wounds. Factors that lead up to chronic wounds are venous disease, infection, diabetes and metabolic deficiencies of the elderly. Careful wound care can speed up the stages of wound healing by keeping wounds moist, clean and protected from re-injury and infection.

21. Phase Onset Peak Durat’n Patho-physiology Wound strength Manage’t Traumatic inflammation 12 h 24-48 h Vascular response; bleeding, oedema Cellular ( phagocytosis ) response; leucocytes, macrophages Negligible RI(C)E Proliferation of fibroblasts 12 h 2-5 days 10 days Fibroblasts proliferate, migrate & bridge wound edges by 5 d Some Rest Elevation Collagen (fibroplasia) 5 days 3 mths 6 mths Collagen fibrils: initially weak random fibrils, later strong flexible fibres depending on stress placed on them Rapid rise Split repaired tissue Exercise Remodelling 1 mth + ongoing 2 yrs + Collagenase removes excess collagen, fibroblasts contract, & there is vascular & wound shrinkage Cont’d gradual rise Exercise & Return of func’n

22. Tissue Early healing (movement without stress) [weeks] Consolidated healing (can take full stress) [weeks] Skin 1 3 Tendon to tendon 3 6-12 Tendon to bone 3 6-12 Ligament repair As for tendon As for tendon Nerve 3 6 Bone to bone 3 6-12 These healing times vary according to age, local blood supply & general condition of person

23. Principles of Prevention &/or Correction Musculoskeletal structures are often intact , & so require treatment consisting of Positioning to avoid deformity ROM exercises to max. range available Functional splinting Functional activities After inflammation has settled , gentle prolonged stretch assists with alignment of collagen fibres Control edema early – elevation, mobilization Keep joints as mobile as possible

24. Diseases That Affect The Muscular System The role of the muscular system is to help in maintaining a good posture of the body, allows movement, helps in pumping blood to the organs, assists in daily functions like sitting, eating, standing, talking, etc. Muscular dystrophy : The genes are responsible for this disease and it damages the fibers in muscles. A person suffering from this faces weakness, lack of coordination and mobility. Dermatomyositis : This is an inflammatory disorder of the muscles and the disease is triggered by bacterial, parasites and viral infections. The signs are rashes on face, elbows, chest, etc. in purple color. In this condition the muscle pain arises along with tenderness, weight loss and fatigue and the condition becomes worse with time.

25. Diseases That Affect The Muscular System Amyotrophic lateral sclerosis : This muscle disease is also known as “Lou Gehrig’s disease,” which is a neurodegenerative disease that is progressive and it hampers the nerve cells of the brain. The voluntary movement of muscles becomes problematic in this condition and one cannot speak, swallow or breathe that ultimately results in paralysis and causes death. Fibromyalgia: This is a chronic disorder in muscles where one experiences pain in the muscles, fatigue, tenderness as well as stiffness. This disease is not easy to diagnose because the symptoms reflect other diseases as well.

26. Diseases That Affect The Muscular System Cerebral palsy: This is a muscle disease which hampers the balance, posture and motor functions. This is a common congenital disorder which damages the brain of child during or before the child is born causing problems in brain that makes it complicated to perform everyday activities. Compartment Syndrome: When the pressure in the muscles becomes highly elevated, this muscle disease is caused. The syndrome is classified as chronic and acute where chronic syndrome is caused due to exercising which is not an emergency and in acute compartment syndrome one experiences tightness, muscle pain, tingling and numbness.

27. Diseases That Affect The Muscular System Myotonia : After contraction and relaxation the muscles relax in a slow manner in this condition. In this disease a person experiences trouble while walking, siting, sleeping and even getting up. Myasthenia gravis: This is a chronic autoimmune disease which causes weakness in muscles and fatigue. Brain fail to control these muscles because of the breakdown in neuromuscular junction where breathing as well swallowing becomes a problematic task. Myofascial pain syndrome: This is a chronic muscle pain disorder where the sensitive points of the muscles are affected and one experiences aches, joint stiffness and burning sensation. Toxin injections, massage therapy and physical therapy is needed to treat this disease.

28. Biomechanical Approach The biomechanical approach is a remediation or restoration approach, and the intervention is designed to restore or establish client-level factors of structural stability, tissue integrity, range of motion (ROM), strength, and endurance. Used to treat disabilities secondary to sudden or cumulative trauma or disease affecting: Musculoskeletal system = orthopedic injuries/surgery, arthritis Spinal cord = paraplegia & tetraplegia Peripheral nervous system = ulnar, median, radial nerve injuries, brachial plexus Integumentary (skin) system = burns Cardiopulmonary system = COPD, cardiac dysfunction

29. Biomechanical Approach Problems identified & treatment goals established based on principles of biomechanical & physiological function & change. Biomechanical concepts provide basis for OT roles in: Primary Prevention – interventions BEFORE onset of disease e.g. back-care programs, OOS/CTD prevention Secondary Prevention – early treatment to prevent condition worsening or becoming permanently disabling e.g. joint protection, energy conservation, positioning, orthotics Tertiary Prevention – reducing disability as an after-effect of disease or condition through remediation, prevention of further loss, & compensation for chronic impairment.

30. Maintaining or Preventing Limitation of ROM Consider P athomechanics of deformity ( T he mechanics of living systems in motion resulting in, or leading to, dysfunction or injury) Immobilization reduces ROM (Immobilization refers to the process of holding a joint or bone in place with a splint, cast, or brace) Methods: Compression Positioning Movement through full ROM

31. Compression Prevents ROM limitation secondary to edema Edema controlled by compression e.g. Coban wrap, stockinette , etc Observe skin color regularly to confirm circulation is preserved Most effective when combined with positioning & passive or active movement of limb

32. Positioning Positioning of weak limbs in resting or functional position essential to prevent deformities & contractures Avoid all potentially nonfunctional positions (day & night) Position opposite to normal pattern of tightness Use orthoses, braces, pillows, rolled towels, positioning boards, etc.

33. Movement through full range of motion Flexibility is the range of motion around a joint , and can refer to ligaments, tendons, muscles, bones, and joints. . For example , the elbow, which is a hinged joint, only permits movement in one direction, but it should provide full range of motion from extension to flexion. - AROM – client performs movement (active range of motion) PROM – therapist performs movement (passive range of motion) Exception : person with tetraplegia who relies on tenodesis action for grasp PROM can be performed by external devices (e.g. CPM) AROM preferred to PROM for edema reduction OT – structure activity to provide AROM

34. Movement through full range of motion Ranging – movement through full ROM Teach client to move joints that are injured, immobilized, edematous If active ROM not possible, use passive ROM Ranging technique similar for AROM & PROM Each involved joint is slowly & gently moved 3x, twice/day from 1 limit of motion to the other.

35. Increasing Range of Motion Occupation & exercise: CAN improve ROM for contractures of soft tissue – skin, muscles, tendons & ligaments CANNOT improve ROM for : Bony ankylosis or arthrodesis ( bony ankylosis = union of the bones of a joint by loss of articular cartilage, resulting in complete immobility. extracapsular ankylosis that caused by rigidity of surrounding parts) ( Arthrodesis = surgical immobilization of a joint by fusion of the bones. Long-standing contractures with extensive fibrotic changes in soft tissue Severe joint destruction (including subluxation) Use compensatory interventions (i.e. teaching techniques or providing equipment) if restorative techniques not possible.

36. Increase Range of Motion - Stretching Stretching: Tissue lengthened by external. force to point of max. stretch i.e. few degrees beyond point of discomfort & held for 15-30 secs Force, speed, direction & extent of stretch must be controlled Force: enough to put tension on tissue but not rupture it Speed: slow to allow tissue to adjust gradually Direction: exactly opposite to tightness Extent: to point of max. stretch

37. Increase Range of Motion - Stretching Gentle stretch that achieves small increments over time is more effective than vigorous stretching. Maintained gentle stretch is more effective, but gains also noted with brief (15-30 secs) stretch. Residual pain after stretching indicates stretch was too forceful & caused tearing of soft tissues or blood vessels. Gentle prolonged stretch assists with alignment of collagen fibres after inflammation has settled

38. Increase Range of Motion – Active Stretch Muscle contraction is source of force Use occupation for treatment Interesting & purposeful activity results in increase ROM because : Person is relaxed, Not anticipating pain, Motivated to complete task, More likely to move as activity demands Select activity with meaning for client Analyze how it is performed To increase ROM , must provide gentle active stretch using slow repetitive isotonic contractions of muscles opposite to contracture, or prolonged passive stretch. ROM increased slightly beyond limitations Monitor movements & ROM used

39. Increase Range of Motion – Active Stretch Adapt/modify if necessary to increase ROM Often done by physio OT may need to do prior to engaging in occupation. Techniques: Manual stretch Orthoses

40. Precautions for Passive Stretching Inflammation weakens structure of collagen, be cautious – slow, gentle motion Sensory loss prevents monitoring of pain Avoid overstretching - can cause int. bleeding & scar formation and can result in heterotopic ossification Weights provide resistance , monitor to ensure slow and gentle stretch

41. Stretching has an impact on both contractile and non-contractile soft tissues. Passive stretching to the elastic limit can allow these tissues to resume the original resting length. Passive stretching beyond the elastic limit into plasticity will lead to a greater soft tissue length compared to the original resting length when the stretch is removed. Prolonged lengthening of the contractile units of muscle , the sarcomeres, into the plastic ROM progressively leads to increased soft tissue length due to an increased number of sarcomeres in series.

42. Non-contractile units of muscle are ligaments, joint capsule, and fascia which all consist of collagen and elastin fibers. Prolonged lengthening of collagen up to its yield point leads to tissue lengthening due to permanent tissue deformation. Elastin fails without deformation with high loads. The more elastin the tissues contain , the more flexible the tissues. To avoid damaging soft tissues , healing and remodeling time must be allowed between periods of stretching.

43. Indications: Essential for establishing normal ROM of joints and soft tissue Important decreasing risk of injury to the musculotendinous unit Prevent contractures and adaptive shortening Combats the effects of prolonged immobilization Optimal flexibility will reduce stresses to surrounding joints and tissues Contraindications: Do not stretch… Around acutely inflamed or infected joints Patients who are already hypermobile Patients when shortened muscles are providing stability if normal joint stability is decreased or assists with functional abilities such as in persons with paraparesis Across a joint when a bony block prevents motion

44. Guidelines and Precautions: It is optimal to warm up before stretching vigorously To increase flexibility, the muscle must be overloaded or stretched beyond its elastic ROM, but not to the point of pain Exercise caution when stretching muscles around painful joints Avoid over-stretching ligaments and capsules that surround joints Use caution if history of steroid use Use caution stretching patients with known or suspected osteoporosis, or who have been on prolonged bed rest Ballistic stretching should be done only by patients who are already flexible Stretching should be performed at least 3 times per week, but between 5 and 6 will yield maximal results Use caution stretching patients with frail integument Use caution stretching older patients because their collagen loses its elasticity and they have reduced capillary blood supply.

45. Muscle Contraction Concentric contraction In concentric contraction , muscle tension is sufficient to overcome the load, and the muscle shortens as it contracts. This occurs when the force generated by the muscle exceeds the load opposing its contraction. During a concentric contraction , a muscle is stimulated to contract according to the sliding filament theory. This occurs throughout the length of the muscle, generating a force at the origin and insertion, causing the muscle to shorten and changing the angle of the joint. In relation to the elbow , a concentric contraction of the biceps would cause the arm to bend at the elbow as the hand moved from the leg to the shoulder A concentric contraction of the triceps would change the angle of the joint in the opposite direction, straightening the arm and moving the hand towards the leg.

46. Eccentric (isotonic) contraction In eccentric contraction , the tension generated is insufficient to overcome the external load on the muscle and the muscle fibers lengthen as they contract. Rather than working to pull a joint in the direction of the muscle contraction, the muscle acts to decelerate the joint at the end of a movement or otherwise control the repositioning of a load . This can occur involuntarily (e.g., when attempting to move a weight too heavy for the muscle to lift) or voluntarily (e.g., when the muscle is 'smoothing out' a movement)

47. Isometric contraction An isometric contraction of a muscle generates tension without changing length. An example can be found when the muscles of the hand and forearm grip an object; the joints of the hand do not move, but muscles generate sufficient force to prevent the object from being dropped.

48. Strengthening Intervention to increase strength is warranted if limitations in strength prevent participation in occupations or may lead to deformity. To increase strength , occupation or exercise parameters can be adjusted: Type of contraction Intensity or load Duration of contraction Rate or velocity of contraction Frequency of exercise/activity Muscle will only gain strength within ROM that is exercised & speed of contraction is specific.

49. Strengthening Occupations & Exercise Both can be used to increase strength May combine exercise with occupation - Exercise as warm-up, then onto occupation Exercise may be valued occupation in itself

50. Strengthening - Grading Muscle Strength Parameters Type of contraction - Isotonic (concentric or eccentric) or isometric Intensity or load - Amount of resistance applied Duration of contraction - increase duration causes fatigue of active muscles. As fatigue progresses more motor units are recruited. Grade rest breaks Rate or velocity of contraction - No. of repetitions/period of time. Grade to avoid over-stressing Frequency of exercise/activity - No. of times per day or per week

51. Strengthening - Grading Muscle Strength Parameters

52. Strengthening Isometric Trace (1) muscle grades Use isometric exercise Use passive exercise to maintain ROM. Force of contraction is not sufficient to move body part Weak muscle is isometrically contracted with rest periods Max. isometric contraction contraindicated for clients with cardiac disease or hypertension

53. Strengthening – Dynamic Active Assistive Poor minus (2-) or Fair minus (3-) muscle grades Active Assistive ROM Muscle can only move through partial available ROM in either gravity-eliminated or against-gravity plane Poor (2) muscle grade Move through full available ROM in gravity eliminated plane Use active ROM Fair (3) muscle grade Move through full available ROM against gravity Use active ROM

54. Strengthening – Dynamic Active Assistive Poor + (2+), Fair (3) muscle grades Move in gravity-eliminated plane with resistance Use active resistive ROM Fair + (3+), Good (4), Good + (4+) muscle grades Move against gravity with resistance Use active resistive ROM

55. Grade Definition Strengthening Approach Zero Passive ROM 1 (T) Trace Isometric activity ; Passive ROM 2- (P-) Poor minus Dynamic (Active) Assistive – gravity eliminated 2 (P) Poor Dynamic Active – gravity eliminated 2+ (P+) Poor plus Dynamic Active Resistive – gravity eliminated + varying resistance 3- (F-) Fair minus Dynamic (Active) Assistive – against gravity 3 (F) Fair Dynamic Active – against gravity 3+ (F+) Fair plus Dynamic Active Resistive – against gravity + varying resistance 4- (G-) Good minus Dynamic Active Resistive – against gravity + varying resistance 4 (G) Good Dynamic Active Resistive – against gravity + varying resistance 5 (N) Normal

56. Increasing Endurance Increase duration at 40%-60% of repetition maximum Use moderately fatiguing activity for progressively longer periods of time with rest intervals Grade by increasing number of repetitions performed (i.e. duration of activity) and/or frequency of activity

57. Purposeful Activity to Improve Strength & Range of Motion Research Task embedded exercise Endurance ROM Challenge to Occupational Therapy How to improve/maintain strength, ROM & endurance, yet avoid providing “just exercise” How is what we do different to physiotherapists or exercise physiologists?

58. Purposeful Activity to Improve Strength & Range of Motion Consider task/activity demands Potential for grading Type of muscle action required Explain need & offer choice Use assistive equipment Wrist-Hand orthoses O verhead slings BFOs/MAS

59. Grading – Motor/Biomechanical Strength  or  amount of resistance Change plane of movement: gravity assisted  gravity eliminated  against gravity Add weights to client, equipment;  weight of tool Grade texture of materials: soft  hard; fine  rough Large resistance & few repetitions Hold against resistance Slow  fast movements

60. Grading – Motor/Biomechanical Range of Motion Position materials/equipment to  reach or active ROM Adapt equipment/tools to require active stretching or accommodate limited ROM Provide controlled stretch/traction

61. Grading – Motor/Biomechanical Endurance & Tolerance Light  heavy work  or  duration/time of performing activity FITT : Frequency, Intensity, Time, Type Order : Time/duration  frequency  intensity Oedema Use extremity in elevated position; use isotonic contraction