Carpal tunnel syndrome an occupational hazard facing dentistry · 2018-12-20 · REVIEW ARTICLE Carpal tunnel syndrome – an occupational hazard facing dentistry Sagar Abichandani,

REV IEW ART ICLE

Carpal tunnel syndrome – an occupational hazard facingdentistry

Sagar Abichandani, Saquib Shaikh and Ramesh Nadiger

Prosthodontics, SDM college of dental sciences, Dharwad, India2; 32; 3 .

Background: The authors wished to evaluate the comprehensive literature on carpal tunnel syndrome to discover workspecific to carpal tunnel syndrome among dentists in order to determine whether there is any correlation with dentistshaving a higher prevalence of its occurrence. Methods: A review of dental literature involving carpal tunnel syndromewas undertaken. Details appearing in the literature before 1995 was reviewed in a comprehensive manner and the litera-ture after 1995 was reviewed electronically. Results: The prevalence of carpal tunnel syndrome is higher in dental profes-sionals involved in various aspects of dental specialties5 . Conclusions: Abnormal postures, including muscle imbalances,muscle necrosis, trigger points, hypomobile joints, nerve compression and spinal disk herniation or degeneration mayresult in serious detrimental physiological changes in the body. These changes often result in pain, injury or possible neu-roskeletal disorders. Clinical implications: Dentists have an increased risk of carpal tunnel syndrome and precautionsand care should be exercised to prevent detrimental irreversible changes occurring.

Key words: Carpal tunnel syndrome, musculoskeletal disorders

INTRODUCTION6

The formation of a deep arch anteriorly at the wristby the carpal bones and the flexor retinaculum iscalled the carpal tunnel1. Medially, the pisiform andthe hook of the hamate form the base of the carpalarch, while laterally it is formed by the tubercles ofthe scaphoid and trapezium7 . The carpal arch isbecomes the carpal tunnel when the flexor retinacu-lum, which is a thick connective tissue ligament,bridges the space between the medial and lateral sidesof the base of the arch. The four tendons of the flexordigitorum profundus, the four tendons of flexor digi-torum superficialis and the tendon of flexor pollicislongus pass through the carpal tunnel, as does themedian nerve. The tendons of the bone plane at thewrist are held by the flexor retinaculum, preventingthem from ‘bowing’. Synovial sheaths facilitate freemovement of the tendons in the carpal, which sur-rounds the tendons. Carpal tunnel syndrome (CTS) isan entrapment syndrome caused by the pressure onthe median nerve within the carpal tunnel.

MATERIALS AND METHODS

A review of the dental literature pertaining to carpaltunnel syndrome was undertaken. Details appearing

in the literature before 1995 were reviewed in a com-prehensive manner and the material after 1995 wasreviewed electronically. Electronic searches of the lit-erature were performed.Various combinations of key words (carpal tunnel

syndrome, musculoskeletal disorders, tenosynovitis)were used in MEDLINE, in various combinations, toobtain potential references for review. A total of 245English language titles were obtained, many of whichwere duplicates because of multiple searches. Thetitles were reviewed and selected for closer examina-tion. If the article under review was a study of anytype, hand-searching of the MEDLINE reference listwas performed to identify any articles missed in theoriginal search.

AETIOLOGY

Complications in symptoms and increased healingtime can result from any previous neck injury orinjury to the upper body2. A systemic or a biochemi-cal factor could be an additional component, which,even without any repetitive movement, can bring onan inflammatory condition. The risk of a narrow tun-nel can be increased by genetic or anatomical factors,such as race or gender. Hamann et al.3 stated thatrepetitiveness of work, forceful exertions, mechanical

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© 2013 FDI World Dental Federation 1

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stress, posture, temperature and vibration are ergo-nomic risk factors associated with CTS. These riskfactors are present for dentists as contact stress overthe carpal tunnel may be caused by dental instru-ments, and wrists may be held in awkward positionsfor prolonged periods.

PREDISPOSING FACTORS

• Genetic predisposition: the carpal tunnel is smallerin some people than in others

• Repetitive movements: Franklin et al.4 stated thatpeople who repeatedly do the same movementswith their wrists and hands may be more likely todevelop CTS. Thus, people with certain types ofjobs are more likely to have CTS, including den-tists, manufacturing and assembly line workers,grocery store checkers, violinists and carpenters. Inaddition, CTS can be caused by some hobbies andsports that use repetitive hand movements, such asgolfing, knitting and gardening

• Injury or trauma: Sesto et al.5 stated that swellingand pressure on the nerve can be caused by a sprainor a fracture of the wrist, increasing the risk of CTS.Strong vibrations caused by heavy machinery orpower tools, along with forceful and stressful move-ments of the hand and wrist, can also cause trauma

• Pregnancy: Atroshi I et al.6 stated that pregnantwomen, especially during the last few months, areat greater risk of getting CTS because of hormonalchanges during pregnancy and the build up of fluid.Most doctors treat CTS in pregnant women withwrist splits or rest rather than surgery, as CTSalmost always goes away following childbirth

• Menopause: during menopause, hormonal changescan put women at greater risk of getting CTS. Inaddition, the wrist structures become enlarged insome postmenopausal women, which can press onthe wrist nerve

• Breast cancer: some women who have a mastec-tomy may get lymph oedema, where the build-up offluids goes beyond the lymphatic system’s ability todrain it. This causes pain and swelling of the arm

• Other medical conditions: people suffering fromdiabetes, hypothyroidism, lupus, obesity and rheu-matoid arthritis are more likely to get CTS. In someof these patients, the normal structures in the wristcan become enlarged and lead to CTS.In addition, smokers with CTS usually have worse

symptoms and recover more slowly than non-smokers.

Symptoms

Carter7 found that carpal tunnel syndrome is particu-larly associated with dentists involved in certain tasks,including:

• Repetitive hand motion

• Awkward hand position

• Strong gripping

• Mechanical stress on the palm

• Vibration.Patients typically report pain and pin-and-needles in

the distribution of the median nerve. According toStockstill & Harn SD8 stated symptoms of carpal tun-nel syndrome may include:

• Loss of sense of touch

• Tingling and numbness in hand and fingers

• Pain in shoulder at night, pain in elbow, or swellingin wrist area

• Loss of grip strength in hand

• Pain in wrist when stretched in an extreme posi-tion, such as bending wrist, pointing the fingers tothe floor

• Dropping objects more often than usual

• A burning sensation in the wrist and hand area

• Being unable to unscrew a jar lid

• Tenderness in the wrist area

• More difficult to do tasks such as brushing hair.Stevens et al.9 showed that the findings on physical

examination (signs) are frequently absent or non-spe-cific. Tinel’s sign (tapping on the wrist or over themedian nerve) and Phelan’s signs (forced flexion ofthe wrist) are frequently described. An electromyo-gram can also be used to check for muscle damage,where a needle is inserted into the muscle to recordelectrical activity in that muscle at rest and when con-tracted. Generally, symptoms can be better examinedwhen the patient is not working or holidays when theworker has avoided workplace exposure. On exami-nation, there is wasting of the muscles of the thenareminence, absence of abduction of thumb at meta-carpopharyngeal joint and absence of opposition ofthe thumb. In severe cases, sensation may be perma-nently lost and the muscles at the base of the thumbslowly shrink (thenaratrophy), causing difficulty withpinch. Relatively large number of dentists have a pro-longed median–ulnar latency.Lam & Thurston10 stated that higher rate of hand

and finger pain symptoms are seen among dentiststhan in the general population. This higher rate ofpain is associated with dentists who reportedly worklonger hours.

Examination

Physical examination of the patient’s hands, arms,shoulders, and neck can help determine if the com-plaints are related to daily activities or to an underly-ing disorder, and can rule out other painful conditionsthat mimic carpal tunnel syndrome. The wrist isexamined for:

• Tenderness

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• Swelling

• Warmth

• Discoloration.The muscles at the base of the hand should be

examined for strength and signs of atrophy; each fin-ger should be being tested for sensation. Routine labo-ratory tests and X-rays can reveal:

• Diabetes

• Arthritis

• Fractures.The presence of CTS is suggested if one or more

symptoms, such as tingling or increasing numbness isfelt in the fingers within 1 minute. Doctors may alsoask patients to try to repeat the movements that bringon symptoms.

Tests

Electrodiagnostic tests are often used to confirm thediagnosis. In a nerve conduction study, electrodes areplaced on the hand and wrist. Small electric shocksare applied to measure the speed with which nervestransmit impulses.In electromyography, a fine needle is inserted into a

muscle, the severity of damage to the median nervecan be determined by electrical activity viewed on ascreen. Impaired movement of the median nerve canbe seen by ultrasound imaging. Magnetic resonanceimaging can show the anatomy of the wrist, but untilnow has not been especially useful in diagnosing car-pal tunnel syndrome.

DENTAL IMPLICATIONS AND CLINICAL FEATURES

Valachi11,12 stated that procedures carried out certaindental specialties have increased incidence of carpaltunnel syndrome.

Endodontics

Biomechanical shaping of the root canals over longhours requires repeated usage of hand-files that canpredispose a dentist to CTS.

Periodontics

Constant use of ultrasonic scalers can predispose adentist to CTS not only because of increased vibra-tions and repetitive movements but also because ofawkward positioning over prolonged periods.

Prosthodontics

A constant prolonged static position during toothpreparation using an aerator handpiece can predisposeto CTS.

ORAL SURGERY

Working on maxillary premolars involves jerky, repet-itive movements 8with awkward positioning of themusculoskeletal system for prolonged periods; this canpredispose dentists to CTS during tooth extraction.Muscles, tendons, ligaments and nerves in the hands

and forearms are repeatedly overworked and stressowing to the use of older, low-speed handpieces.These were designed with very heavy motors at oneend and thus require unnecessary leverage just to con-trol the unbalanced weight during each dental proce-dure.Modern handpieces are better to handle and use as

they are shorter, made with lighter-weight durablematerials, and often weigh about 85 g 9–two-thirds lessthan older models. In modern designs the weight isevenly distributed over the entire length of the hand-piece rather than concentrated at the hose-end connec-tion, making it easier to handle. They also come witha variety of swivel mechanisms that reduce unneces-sary torque on the hand, wrist, forearm and elbow.Different types of handpiece profile such as straight,

cylindrical or tapered (wider at the hose-end connec-tion) are available. Overall pinch/grip can be reducedby flared or tapered handpieces. The back end of thehandpiece is supported and balanced by the soft tissuebetween the thumb and index finger. Pinch/grip isaffected by the texture on the handpiece shaft. Tex-ture improves traction and the clinician’s ability tograsp the handpiece lightly while still maintainingcontrol, especially in a moisture-laden environment isimproved by any texture or ribbing. To stabilize theprophy angle, one should ensure that the currenthandpiece is in good running order, maintained regu-larly and has a proper locking mechanism. However,one should also regularly check the availability ofmore ergonomically sound handpieces.Conrad & Conrad13 stated that a design that neces-

sitates more wrist flexion and extension for reachingtooth surfaces, also where majority both metal andsingle-use prophy angles are right-angled 10. Similar tothe bend of a high-speed handpiece, contra-angledprophy angles have a small 4 mm bend in the shaft.The clinician can keep his or her wrist in a neutralposition as this reduces stress on the wrist and fore-arm. An adjustable contra-angled DPA 11is ideal for usewith a non-swivelling handpiece.Osborn & Newell14 stated that hand comfort is

directly affected by cup stability. Spinning screw- orlatch-mounted cups remain concentrically stable dur-ing polishing, in contrast to the wobble created bysnap-on cups, which create unnecessary hand stressfor the clinician.Advancements in rotary instruments for endodon-

tics have not only resulted in decreased perception of

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vibrations but also increased durability by reducingthe need for hand-filing for biomechanical shaping ofroot canals.Often, dentists assume static postures, which

require more than 50% of the body’s muscles to con-tract to hold the body motionless while resisting grav-ity. The static forces resulting from these postureshave been shown to be much more taxing thandynamic (moving) forces.A series of events that may result in pain, injury or

a career-ending MSD12 can be initiated when thehuman body is subjected repeatedly to PSPs13 15. Someof the physiological consequences of PSPs are muscleimbalances, ischaemia, trigger points, joint hypomo-bility and spinal disk degeneration.To recover from even very low-level exertion,

human muscles require rest periods as they are notadapted for continuous long-lasting contractions. Dur-ing a sustained, static muscle contraction, the tendonstretches and compresses the vascular supply to themuscle and surrounding tissues, thereby depleting thenutrient and oxygen supply. Lactic acid and othermetabolites then accumulate in the muscle tissues,which can result in damaged muscle tissue and a pain-ful sensation.Under normal conditions, damaged tissue is

repaired during rest periods. However, in dentistry,because of insufficient rest periods the damage oftenexceeds the rate of repair and can result in musclenecrosis. If this occurs the body uses another part ofthe damaged muscle to maintain the body position inorder to protect the stressed area from further injury.As the body recruits different muscle groups to per-form the needed task long periods, entire musclesbecome compromised. This is known as muscle substi-tution and muscles are required to perform a task forwhich they are not ideally designed. An abnormal‘compensatory’ motion then develops and predisposesthe person to joint hypomobility (stiffness) and nervecompression.Early intervention could be important for people

who have symptoms of CTS or are at an increasedrisk of developing the condition. When recognizedearly, CTS can be managed effectively with conserva-tive and non-invasive treatment, as suggested byCorks16.The highest risk of injury occurs at the median

nerve because of the extremes of wrist flexion andextension position; thus the most common interven-tion is the use of a night-time wrist splint. This devicehelps the patient avoid extremes of wrist flexion andextension during sleep, decreasing the pressure on themedian nerve. As extended wrist flexion or extensioncan place the median nerve at risk, pacing of workactivity can be helpful to reduce the pressure on thenerve and prevent injury.

Bramson & Smith17 stated that management ofergonomic stressors could include the use of fittedgloves that reduce hand tension and Avoidance ofawkward wrist posture during procedures reduces thestress on the median nerve. Early recognition ofsymptoms and education regarding ergonomic riskfactors is important in the successful management ofCTS.

TREATMENT

Fish & Morris-Allen18 stated that symptoms mayoften be relieved without surgery. Some ways toreduce pressure on the nerve are identifying and treat-ing medical conditions, changing the patterns of handuse, or keeping the wrist splinted in a straight posi-tion. Wearing wrist splints at night may relieve thesymptoms that can interfere with sleep. Swellingaround the nerve can be relieved by a steroid injectioninto the carpal tunnel. However, surgery may beneeded to make more room for the nerve when symp-toms are severe or do not improve. Pressure on thenerve is decreased by cutting the ligament that formsthe roof (top) of the tunnel on the palmar side of thehand. Incisions for this surgery may vary, althoughthe goal is the same: to enlarge the tunnel anddecrease pressure on the nerve. Soreness around theincision may last for several weeks or months, follow-ing surgery. The numbness and tingling may disappearquickly or slowly and it may take several months forstrength in the hand and wrist to return to normal.However, the symptoms of CTS may not resolve aftersurgery, especially in severe cases.According to Guay19 some precautions would be:

keep the wrist at relaxed, middle position withoutbending it completely up or down; use a relaxed grip;and use less hand and finger force when performingtasks. It is important to strive for good posture so thatneck and shoulder muscles do not compress nerves inthe neck, which affects the wrist and hands.

• Wrist Splint: Field et al.20 recommend that thewrist be supported and braced by wearing a splintin a neutral position so that the nerves and tendonscan recover. A splint can be worn 24 hours a dayor only at night. Wearing a splint at night some-times helps to reduce the pain. Splinting can workthe best when done within 3 months of having anysymptoms of CTS

• Rest: stopping or doing less of a repetitive move-ment may be all that is needed, for people withmild CTS. Your doctor will advice you about thesteps that should take to prevent CTS from comingrecurring. These steps will include rest, stretchingand bending the hand and wrists at intervals of20 minutes, alternating tasks and changing workposition frequently. It is important to be aware of

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any onset of headaches, fatigue or muscle pain dur-ing activities.

Other assistance

Stress and pain can be reduced by relaxation tech-niques such as those found in yoga. Water therapy,heat and massage might be useful in relieving symp-toms.

Ergonomics

Valachi & Valachi11,12 indicated that effective andefficient design of the workplace is key. A huge vari-ety of equipment , such as wrist and forearm sup-ports, sprints and braces, work surfaces, chairs andother innovative devices, is available to ensure correctposture and good wrist position. Werner & Arm-strong 21 stated that its imperative to take care toadjust equipment to avoid stress from awkward bodypositioning and wrist angles.

Medication

Patient leaflets from the BMJ group states that forcontrolling CTS pain, the short-term use of nonsteroi-dal anti-inflammatory drugs (NSAIDs) may be helpful.These include aspirin, ibuprofen and other non-prescription pain relievers. In severe cases, swellingmay be reduced with the help of an injection of corti-sone or with corticosteroids in pill form. However,these treatments only relieve symptoms temporarily. IfCTS is caused by another health problem, this willprobably be treated first. If diabetes is present, it isimportant to be aware that long-term corticosteroiduse can make it harder to control insulin levels.

Physical therapy

Ashworth22 advised that physical therapists can helpwith special exercises to make wrists and hands stron-ger. Massage, yoga, ultrasound, chiropractic manipu-lation, and acupuncture are just a few such optionsthat have been found to be helpful to improve CTSand relieve symptoms.Massage treatment consists of moderate stroking

techniques from the fingertip to elbow region. Thetechnique is described as ‘stroking the wrist up to theelbow and back down on both sides of the forearm’,after which another technique, described as ‘a wring-ing motion applied to the same area.’ is applied.These appear to be petrissage-type techniques. Twomore techniques are described as part of the massageprocess. The first is stroking using the thumb andforefinger in a circular back-and-forth motion cover-ing the entire forearm and hand. The final technique

described is rolling the skin between the thumb andforefinger across the hand and up both sides of theforearm. It is advisable to first consult a doctor beforetrying these alternative treatments.

Surgery

Surgery for CTS is one of the most common proce-dures done in the USA Generally, surgery is only anoption for severe cases of CTS and/or after othertreatments has failed for a period of at least6 months. A common surgical approach to CTS is anopen release technique, which involves making a smallincision in the wrist or palm and cutting the ligamentto enlarge the carpal tunnel. This surgery is done asan outpatient procedure under local anaesthetic tonumb the wrist and hand area.

OVERVIEW OF THE TREATMENT MODALITIES

An overview of medical treatment modalities, as pro-vided by the Washington State Department of Laborand Industries23 guidelines, are given below.

Conservative

• Corticosteroids (local injection/systemic)

• Diuretics

• NSAIDS

• Pyridoxine

• Large doses of vitamin B6

• Acupuncture

• Massage

• Nerve and/or tendon exercise

• Therapeutic ultrasound

• Wrist splints.Hamann et al.3 stated that whether the patient can

remain at work is primarily dependent on the dura-tion of conservative treatment. Regardless of whetherspecific treatment is rendered, most patients willimprove when they are off work. In some cases, wors-ening of OCTS 14can be prevented and symptoms maybe improved by modification of the job, along withconservative treatment. If modification is not possible,or if the claimant cannot continue working with con-servative treatment, then surgery should be consideredas a treatment option.

Surgery

Surgical options, as suggested by The American Soci-ety for the Surgery of Hand24, are:

• Endoscopic carpal tunnel release and open carpeltunnel release

• Internal neurolysis in conjunction with open carpaltunnel release.

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For OCTS the surgical procedure of choice isdecompression of the transverse carpal ligament. Ingeneral, the following criteria should have been metfor authorization of surgery to occur:1 The clinical history should be consistent with

OCTS2 Nerve conduction testing (NCV) should have dem-

onstrated a conduction slowing of the medianmotor or sensory fibres across the carpal tunnel

3 A course of conservative management must havebeen tried.

According to various studies, it is suggested that60–90% of the post-surgical cases, the burning painassociated with OCTS will be alleviated. The patient’sability to return to the same job is not clear. If painpersists or recurs, NCVs can help sort out whethernerve entrapment continues to be a problem.

Acupressure

Acupressure is based on the same principles asacupuncture. Pressure is applied instead of needles toacupuncture points, which is thought to stimulateblood flow to the wrists and hands and ease numbnessand swelling in the area.Acupressure points for carpal tunnel syndrome are

typically on the wrists, forearms and hands.Kiernan & Mogyoros25 described that with the

thumb or middle finger at a 90 degree angle to theskin, apply gradually increasing pressure. Hold for2–3 minutes. Each point will feel different; it may beachy, sore or tense. The pressure should not be pain-ful or uncomfortable (don’t try to bore a hole intoyour arm!). The points do not have to be usedtogether to be effective, so choose the most tensepoints if you do not have time for the whole routine.

Post surgery

Guidelines after surgery, as provided by the Universityof Pittsburgh Medical Center information for patientssection26, include:

• Medicine: take the prescribed pain medication andan antibiotic as directed by your doctor

• Elevation: it is important to keep the hand raisedabove the level of the heart as much as possible forthe first 48 hours following surgery as this helps toreduce swelling and pain

• Dressing: keep the dressing over the incision cleanand dry until the follow-up appointment with yourdoctor, unless instructed otherwise. The stitchesunder the dressing will be removed by a doctor

• Activity: do not lift anything with the hand youhad surgery on until your doctor says it can beused. Move the fingers regularly as this will keep

them from getting stiff and help lessen the swell-ing.

Prognosis

By changing the way they do repetitive movements,the frequency of these movements and the amount oftime rest between periods of performing these move-ments, the majority of patients recover completelyand can avoid re-injury.

CONCLUSION

Abnormal postures, including muscle imbalances,muscle necrosis, trigger points, hypomobile joints,nerve compression and spinal disk herniation ordegeneration may result in serious detrimental physio-logical changes in the body. These changes oftenresult in pain, injury or MSDs 15.Clinical work habits, including proper use of ergo-

nomic equipment, frequent short stretch breaks andregular strengthening exercise may require a paradigmshift within the dentistry profession to prevent chronicpain.

Acknowledgements

We acknowledge the time and efforts put in by thetechnical and non-technical staff for helping us com-pile our data and for their timely cooperation.

Conflict of interest

None declared.

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17. Bramson JB, Smith S, Romagnoli G. Evaluating dental officeergonomics: risk factors and hazards. JADA 1998 129: 174–183.

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19. Guay AH. Commentary: ergonomically related disorders indental practice. JADA 1998 129: 184–186.

20. Field T, Diego M, Cullen C et al. Carpal tunnel syndromesymptoms are lessened following massage therapy. J BodywMov Ther 2004 8: 9–14.

21. Werner RA, Armstrong TJ. Carpal tunnel syndrome: ergonomicrisk factors and intracarpal canal pressure. Phys Med RehabilClin N Am 1997 8: 555–569.

22. Ashworth N. Carpal tunnel syndrome. Clin Evid 2010 03:1114–1142.

23. Washington State Department of Labor and Industries. Diagno-ses and treatment of work-related carpal tunnel syndrome(OCTS); Medical Treatment Guidelines Washington StateDepartment of Labor and Industries: Provider Bulletin 95-10;Date Introduced: November. Washington State Department ofLabor and Industries 1995.

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25. Kiernan MC, Mogyoros I, Burke D. Conduction block in carpaltunnel syndrome. Brain 1999 122: 933–941, Oxford UniversityPress 1999. 2323

26. University of Pittsburgh Medical Center Information forPatients. Carpal tunnel syndrome. 24;25

Correspondence to:Dr Sagar Abichandani,

Prosthodontics,SDM college of dental sciences,

Dharwad, India.Email: [email protected] 4

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Author Query Form

Journal: IDJ

Article: 12037

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O n c e y o u h a v e A c r o b a t R e a d e r o p e n o n y o u r c o m p u t e r , c l i c k o n t h e C o m m e n t t a b a t t h e r i g h t o f t h e t o o l b a r :

S t r i k e s a l i n e t h r o u g h t e x t a n d o p e n s u p a t e x tb o x w h e r e r e p l a c e m e n t t e x t c a n b e e n t e r e d .‚ H i g h l i g h t a w o r d o r s e n t e n c e .‚ C l i c k o n t h e R e p l a c e ( I n s ) i c o n i n t h e A n n o t a t i o n ss e c t i o n .‚ T y p e t h e r e p l a c e m e n t t e x t i n t o t h e b l u e b o x t h a ta p p e a r s .

T h i s w i l l o p e n u p a p a n e l d o w n t h e r i g h t s i d e o f t h e d o c u m e n t . T h e m a j o r i t y o ft o o l s y o u w i l l u s e f o r a n n o t a t i n g y o u r p r o o f w i l l b e i n t h e A n n o t a t i o n s s e c t i o n ,p i c t u r e d o p p o s i t e . W e ’ v e p i c k e d o u t s o m e o f t h e s e t o o l s b e l o w :S t r i k e s a r e d l i n e t h r o u g h t e x t t h a t i s t o b ed e l e t e d .

‚ H i g h l i g h t a w o r d o r s e n t e n c e .‚ C l i c k o n t h e S t r i k e t h r o u g h ( D e l ) i c o n i n t h eA n n o t a t i o n s s e c t i o n .

H i g h l i g h t s t e x t i n y e l l o w a n d o p e n s u p a t e x tb o x w h e r e c o m m e n t s c a n b e e n t e r e d .‚ H i g h l i g h t t h e r e l e v a n t s e c t i o n o f t e x t .‚ C l i c k o n t h e A d d n o t e t o t e x t i c o n i n t h eA n n o t a t i o n s s e c t i o n .‚ T y p e i n s t r u c t i o n o n w h a t s h o u l d b e c h a n g e dr e g a r d i n g t h e t e x t i n t o t h e y e l l o w b o x t h a ta p p e a r s .

M a r k s a p o i n t i n t h e p r o o f w h e r e a c o m m e n tn e e d s t o b e h i g h l i g h t e d .‚ C l i c k o n t h e A d d s t i c k y n o t e i c o n i n t h eA n n o t a t i o n s s e c t i o n .‚ C l i c k a t t h e p o i n t i n t h e p r o o f w h e r e t h e c o m m e n ts h o u l d b e i n s e r t e d .‚ T y p e t h e c o m m e n t i n t o t h e y e l l o w b o x t h a ta p p e a r s .

I n s e r t s a n i c o n l i n k i n g t o t h e a t t a c h e d f i l e i n t h ea p p r o p r i a t e p a c e i n t h e t e x t .‚ C l i c k o n t h e A t t a c h F i l e i c o n i n t h e A n n o t a t i o n ss e c t i o n .‚ C l i c k o n t h e p r o o f t o w h e r e y o u ’ d l i k e t h e a t t a c h e df i l e t o b e l i n k e d .‚ S e l e c t t h e f i l e t o b e a t t a c h e d f r o m y o u r c o m p u t e ro r n e t w o r k .‚ S e l e c t t h e c o l o u r a n d t y p e o f i c o n t h a t w i l l a p p e a ri n t h e p r o o f . C l i c k O K .

I n s e r t s a s e l e c t e d s t a m p o n t o a n a p p r o p r i a t ep l a c e i n t h e p r o o f .‚ C l i c k o n t h e A d d s t a m p i c o n i n t h e A n n o t a t i o n ss e c t i o n .‚ S e l e c t t h e s t a m p y o u w a n t t o u s e . ( T h e A p p r o v e ds t a m p i s u s u a l l y a v a i l a b l e d i r e c t l y i n t h e m e n u t h a ta p p e a r s ) .‚ C l i c k o n t h e p r o o f w h e r e y o u ’ d l i k e t h e s t a m p t oa p p e a r . ( W h e r e a p r o o f i s t o b e a p p r o v e d a s i t i s ,t h i s w o u l d n o r m a l l y b e o n t h e f i r s t p a g e ) .

A l l o w s s h a p e s , l i n e s a n d f r e e f o r m a n n o t a t i o n s t o b e d r a w n o n p r o o f s a n d f o rc o m m e n t t o b e m a d e o n t h e s e m a r k s . .‚ C l i c k o n o n e o f t h e s h a p e s i n t h e D r a w i n gM a r k u p s s e c t i o n .‚ C l i c k o n t h e p r o o f a t t h e r e l e v a n t p o i n t a n dd r a w t h e s e l e c t e d s h a p e w i t h t h e c u r s o r .‚

T o a d d a c o m m e n t t o t h e d r a w n s h a p e ,m o v e t h e c u r s o r o v e r t h e s h a p e u n t i l a na r r o w h e a d a p p e a r s .‚

D o u b l e c l i c k o n t h e s h a p e a n d t y p e a n yt e x t i n t h e r e d b o x t h a t a p p e a r s .