81-year-old woman who was presumed to be suffering from polymyalgia rheumatica and was receiving 2.5mg/week of ledertrexate. The patient suffered from chondrocalcinosis of the wrist joints, bilateral arthritis in her hands and repeated bouts of plurifocal synovitis in her wrists and metacarpophalangeal joints. The patient presented for an ultrasound due to Achilles tendon pain due to suspected bilateral Achilles tendonitis.
Multiple hyperechogenic elongated deposits with acoustic shadowing are located within the central part of the right Achilles tendon and following its long axis (Figures 1 and 2), as well as in the left Achilles tendon (Figures 3 and 4). The Achilles tendons are thickened and hypoechogenic. The findings were identical in both Achilles tendons.
Background
Calcium pyrophosphate deposition disease (CPPD) is a common pathology, affecting 4–7% of the adult population in Europe and the USA, but can take diverse clinical forms [1]. The disease may affect single or multiple articulations and may or may not be accompanied by an inflammatory syndrome [1,2]. It may be hereditary or sporadic, with age being the major risk factor [1,2].
Chondrocalcinosis is a common finding in CPPD, though it may also cause geodes, osteophytes and severe joint destruction [1]. In around a quarter of cases, there may be calcifications in the tendons, most often found in the gastrocnemius; though, the tendons of the quadriceps, triceps or, as in this case, the Achilles tendon, have also been reported [1].
Clinical Perspective
Patients with CPPD will oftentimes have a confusing presentation, ranging from asymptomatic to acutely painful, waxing and waning over several months [3]. When affecting the Achilles tendon, the patients may experience differing levels of pain, signs of Achilles tendon enthesopathy and deep retrocalcaneal bursitis [4].
Intra-tendinous calcifications may be an unexpected finding in an exam performed to rule out tendinitis, and thus may help reorientate the diagnosis towards CPPD due to its specificity as an indirect sign of the pathology [5].
Imaging Perspective
When examining a tendon with calcium pyrophosphate deposits using ultrasound, the deposits will appear as multiple hyperechogenic elongated/linear formations with acoustic shadowing along the long axis of the tendon [2]. Ultrasound is particularly useful as it may be able to demonstrate calcifications too small for conventional radiography to detect [5]. Power Doppler may also be used to demonstrate hypervascularisation in the context of inflammation.
Conventional radiography will demonstrate intra-tendinous calcifications in the long axis of the tendon [1].
The role of MRI is limited due to its insensitivity with regard to calcifications [1].
A differential diagnosis for intra-tendinous deposits is hydroxyapatite deposits, though their shapes differ from those of CPPD in that they are more homogeneous, rounded and hypoechoic [5].
Outcome
The demonstration of this sensitive and specific finding for CPPD may help reorientate a patient’s therapy in the context of non-specific symptoms of a hitherto unknown CPPD.
Take Home Message / Teaching Points
Multiple linear hyperechogenic bands along the axis of the Achilles tendon are calcifications, a finding which is sensitive and specific to calcium pyrophosphate deposition disease (CPPD).
All patient data have been completely anonymised throughout the entire manuscript and related files.
Calcium pyrophosphate deposition disease
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This patient is an 81-year-old female who underwent an ultrasound examination due to Achilles tendon pain. The ultrasound images show multiple linear hyperechoic bands along the longitudinal axis of both Achilles tendons, accompanied by acoustic shadowing. Based on their morphology and distribution, these are suspected to be intratendinous calcifications. This finding is consistent with her history of articular cartilage calcification (chondrocalcinosis) in other locations. No obvious signs of tendon rupture or disruption of the tendon fibers were noted, but mild soft tissue thickening around the Achilles tendon suggests possible inflammatory changes.
The patient has a history of chondrocalcinosis (cartilage calcification). Ultrasound shows multiple elongated hyperechoic bands, consistent with intratendinous calcium pyrophosphate deposits, which aligns with the typical presentation of CPPD involving tendons.
Typically presents as more homogeneous, round or rounded echogenic deposits, and may appear partially hypoechoic in some areas. Although it can resemble CPPD, there are morphological differences, making it an important differential diagnosis.
Such as trauma, chronic inflammation, or metabolic diseases, which can lead to peritendinous or localized calcium deposition, but do not fully match the pattern of longitudinal calcification seen here.
Considering the patient's age, past diagnoses (chondrocalcinosis, arthritis of the hands, wrist calcification, etc.), clinical symptoms (Achilles tendon pain), and ultrasound findings (multiple linear hyperechoic bands), the most likely diagnosis is Calcium Pyrophosphate Deposition Disease (CPPD) involving the Achilles tendon.
1. Conservative and Pharmacological Treatment
2. Physical Therapy and Rehabilitation Training
3. Example of an Exercise Prescription (FITT-VP Principle)
4. Special Considerations
This report is based on the current medical history and imaging data for reference only, and does not replace a face-to-face clinical diagnosis or a physician's professional opinion. Actual treatment should be determined by clinical doctors according to the individual conditions of the patient.
Calcium pyrophosphate deposition disease
