3 DECEMBER 2021 ausdoc . com . au rising from bed . The length of time it remains stiff is a measure of the tendon ’ s ‘ happiness ’ and is an excellent outcome measure for assessing progress and response to treatment . Stiffness lasting less than 30 minutes is likely to be a tendinopathy . 10 Consider a systemic inflammatory condition if the stiffness lasts more than 30 minutes , especially if the pain is at the insertion . If the tendon is particularly irritable , stiffness recurs during the day after sitting or resting . 11 The patient will report that stairs , slopes and hills , and walking and changing direction cause pain . Document the changes in activity and the relationship to symptoms , and other factors that impact on symptoms , such as change in footwear , menopause and previous treatments . Because of its recurrence and persistence , many people will have tried interventions to improve symptoms . Ask what treatments have been tried . Were they passive treatments ( injections , hands-on therapies ) or active , exercise-based treatments ? Record which were helpful and the duration of the improvement .
Note that quinolone antibiotics have an important relationship with tendon symptoms and rupture . 12 Symptoms may arise within days and persist for years ; all tendons are vulnerable , but the Achilles is most commonly affected . 13 Treatment options are limited .
EXAMINATION
THE tendon may appear thicker , often localised to the mid-tendon , and there may be a series of discrete lumps , which may be bilateral . Swelling over a greater length of tendon suggests peritendon involvement . Insertional Achilles tendinopathy is more lateral over the superior aspect of the calcaneus ( see figure 2 ).
Ask the patient to point to the location of the pain ; they will point with one or two fingers as tendon pain is not felt over a wide area .
The calf muscle often shows wasting of gastrocnemius , more obvious in the medial head . A longer duration of symptoms is more likely to result in greater muscle wasting ( see figure 3 ).
Loading the tendon with a series of progressively more difficult calf raises is a guide to severity .
A simple double-leg heel raise may not induce pain ; doing the heel raise on a single leg may cause low-level localised pain . If that is not provocative , or if the person is more active , progress the examination to a double-leg jump and finally single-leg hops . The pain will be greater as the load on the tendon is
A
Figure 1 . Healthy Achilles insertion ( left ) and pathological changes at the enthesis in the tendon and the bursa ( right ).
Box 1 . Types of tendon loads
• Energy storage and release loads :
— The most important function of many tendons is to store and release energy , making movements faster and more metabolically efficient . A sprinter will use stored passive energy in their Achilles tendon to propel themselves along a track , and a jumping athlete will use energy stored in the patellar tendon to jump higher .
— This explains why Achilles tendon issues can occur in more sedentary people . They do not jump ( no patellar tendinopathy ) but still impose energy storage loads on their Achilles tendon when they descend stairs and change direction quickly when walking .
• Compressive loads : — These occur at the bone and tendon junction ( the enthesis ) and for the Achilles tendon are greater when the foot is dorsiflexed ( see figure 1 ). — The tendon , bone and bursa are all affected by pathological changes , and symptoms cannot thus be solely attributed to retrocalcaneal bursitis . — Altering the compressive loads by increasing heel height with appropriate shoes and limiting load in dorsiflexion will positively affect pain .
• Friction :
— This is caused by repeated dorsiflexion and plantar flexion , often without load ( eg , cycling ), and irritates the surrounding complex peritendinous tissues . Whether the tissue response is inflammatory or not has not been clearly shown .
— Occasionally the peritendon may be affected by an acute blow to the tendon ( shopping trolley in the back of the leg ) or through sustained external load such as taping and tight socks . The tendon itself is not affected by this type of loading .
increased with faster energy-storing activity , so repeatedly ask about pain location when loading the tendon to confirm that it stays localised .
Longer-term pain will result in dysfunction and a difference between the painful and the unaffected limbs . Inhibition from anticipated pain may make it impossible for the patient to jump or hop , a finding in itself .
B
Examine for muscle strength by asking the patient to first perform a slow , double-leg heel raise ; if this is reasonable , then compare limbs with single-leg calf raises ( supported for balance ). These slow raises should not be painful ( or have low levels of pain ) as there is no energy storage and release loads . It is not uncommon for sedentary people to be incapable of more
C
Image reproduced with permission from FC Barcelona . than five heel raises on either limb . In the more active people , there will be a clear difference between the affected and unaffected limbs .
Cheating strategies to achieve a heel raise include going fast to use connective tissue elasticity instead of muscle strength , inverting to spare the calf muscles and not achieving full height ( see figure 4 ). Palpation is not helpful as positive palpation findings do not indicate that the tendon is the source of the pain . Palpation as an outcome measure is also misleading as tenderness may persist after the patient is fully functional and pain-free . Discourage the patient from repeatedly touching the tendon to ‘ see how it is ’ as this is negative reinforcement .
Examining musculotendinous length is not helpful , as tightness in the muscle has little influence on the tendon . It is more important to examine the range of dorsiflexion , as a limited range of movement is linked to
14 , 15
Achilles tendinopathy ( see figure 5 ). The distance from toe to wall should be at least 8cm .
Outcome measures
Standardised outcome measures — such as the Victorian Institute of Sport Assessment-Achilles Questionnaire ( VISA-A ) — measure pain , function and activity levels . 16
A simpler approach is to document morning pain and stiffness , both the length of time to warm up ( the best measure ) and the level of stiffness and pain ( on the 10-point scale ). Changes in these measures indicate the health of the tendon and its improvement ( or otherwise ).
In those with better function , such as recreational runners , documenting single-leg-hop pain at the same time each day or so is a good objective outcome measure .
Investigations
Imaging offers little benefit , as it is not diagnostic , does not provide prognostic information and is not sensitive to functional recovery . 2 , 17 , 18 A person can return to full pain-free function at a high level of sport with profound tendon pathology on imaging . Asymptomatic abnormalities are present in many tendons and increase with age ( load accumulation ). There are no criteria for reporting on intra-tendinous findings such as partial tear and splitting outside of radiologist opinion , and these reports should not influence management . 19
Because tendon pathology has no capacity to repair , serial imaging of a tendon to study improvement is unhelpful and does not inform treatment or referral decisions .
20 , 21
Ultrasound can image aspects of tendon pathology such as integrity of collagen fascicles and vascularity ( increased Doppler flow ) better than MRI , but as stated it is unhelpful . MRI is touted as improving capacity for differential diagnosis ; however , the same issues arise : all structures can have asymptomatic pathology . 17 , 18 Clinical acumen and testing remain the best diagnostic option .
Figure 2 . Patient-reported pain in Achilles tendon presentations . Note , this is not pain on palpation . A . Insertional AT ( green ). B . Mid-portion AT ( white ). C . Peri-tendon ( yellow ).
DIFFERENTIAL DIAGNOSES
MANY structures in the posterior heel can contribute to local pain . Consider subjective history , behaviour of symptoms and clinical assessment when developing a differential diagnosis . Emphasise distinguishing the potential structures involved in mechanical sources of pain . Common differential diagnoses in the posterior heel include posterior ankle impingement ( see figure 6 ), Sever ’ s disease ( in children / adolescents ) or sural nerve neuropathy . Mixed presentations may also occur . Pain may arise solely from the Achilles tendon or simultaneously from multiple structures , such as the Achilles tendon insertion and superficial bursa .