Mass like calcific peri arthritis of wrist presenting as acute carpal tunnel syndrome: Case report

Hydroxyapatite deposition disease (HADD) is a common localized disorder characterized by deposition of hydroxyapatite in soft tissues. These hydroxyapatite deposits can be found in the periarticular soft tissues such as bursae, joint capsules, tendon sheaths, and ligaments as well as within the tendons themselves, and intra-articular involvement has also been described.

Michal Krolikowski et al present a case of a 50-year-old female with acute symptoms of carpal tunnel syndrome secondary to partially liquified, mass-like, inflammatory calcific peri-arthritis. The case is supplemented with the use of multimodality imaging, a surgical perspective, and histopathologic correlation.

A 50-year-old, right hand dominant, female patient with history of diabetes, major depressive disorder, hyperlipidemia, and tobacco use, presented initially to the emergency department with complaints of acute on chronic right wrist pain. She denied trauma but mentioned a recent increase in repetitive right wrist activity after starting a new job as a line-cook, washing hundreds of dishes nightly.

The physical exam was notable for positive Tinel's sign at the volar wrist and positive Phalen's test. She was provided with a splint and referral to the plastic surgery hand clinic for further management. At the time of clinic evaluation 4 days later, she reported 9/10 pain unrelieved with splinting and use of gabapentin, tramadol, and ibuprofen. She did describe a history of symptoms consistent with carpal tunnel syndrome and had been referred for electromyography the year prior; however, this was not completed. Upon more detailed examination in the plastic surgery clinic, the patient held her right hand in a loose fist due to severe discomfort. Evaluation was remarkable for pain with passive digital extension and edema in the palm and radial three digits. Hand and forearm compartments were soft although the patient did experience paresthesia in the distal right index finger. Wrist pronation was limited by pain; elbow and shoulder range of motion was full.

Laboratory values at the time of the office visit showed elevated ESR and CRP measuring 62 mm/h and 5.4 mg/ dL, respectively, with minimal increase in WBC, measuring 12.9 K/uL. Phosphate levels were normal a year prior to the office visit measuring 3.4 mg/dL and calcium levels were also normal measuring 9.6 mg/dL 1 month prior to the office visit.

Radiographs and non-contrast CT demonstrated amorphous mass-like calcific densities in the deep volar soft tissues of the right wrist. On imaging, these densities originate from the capsule along the volar aspect of the capitate, which was later confirmed surgically, as described below.

Magnetic resonance imaging showed multiple heterogeneous masses along the deep aspect of the flexor tendon compartment extending from the level of the distal radius to the capitate. On T1- and T2-weighted images, the largest component demonstrated heterogeneous layering material suggesting liquefied internal contents, with marked surrounding soft tissue inflammatory edema in the volar aspect of the wrist and distal forearm evident on T2-weighted images. A component of the layering material in the large, encapsulated component is T1 hyperintense, possibly related to its high protein content secondary to recruited inflammatory cells. T1-weighted axial images demonstrated the origin of the abnormal calcifications from the flexor tendon sheath/wrist capsule. The smaller components demonstrated the low T1 and T2 signal intensity typical for hydroxyapatite. There was prominent mass effect on the carpal tunnel and an axial PD SPAIR image demonstrated increased signal diffusely in the thenar muscles relative to the normal signal in the remainder of the hand musculature—a sign of early denervation from median nerve impingement.

Tenosynovitis was also present involving the flexor tendons. Coronal PD SPAIR demonstrated a rim of peripheral calcification around the mass with a central fluid pocket which is more clearly identified on a cartilage sensitive sequence 3D WATS-c. Post contrast T1 SPIR imaging demonstrated lack of enhancement in the mass. After failed conservative management, surgical intervention was recommended given the large size of the calcifications and the carpal tunnel syndrome symptoms.

Surgical exploration with decompression of the carpal tunnel was performed. Traditional open release of the carpal tunnel at the wrist was unrevealing. A proximal midline extension incision was made overlying the palpable mass in the distal forearm. Release of the muscular fascia at this level revealed significant inflammation of the median nerve as well as flexor pollicis longus, flexor digitorum superficialis, and flexor digitorum profundus tendons. Median neurolysis, including the palmar cutaneous branch, was performed, allowing dissection of the calcific mass away from the nerve. Flexor pollicis longus, flexor digitorum superficialis, and flexor digitorum profundus tenolysis allowed visualization of the underlying mass. The calcific mass was opened, with release of a large amount of milky fluid which was evacuated (approximately 30 ml). Subsequently, the inflamed outer rind of tissue was excised, revealing its origin from the volar wrist capsule overlying the capitate. The fluid was sent for crystal analysis and the inflamed outer rind was sent for histopathologic evaluation. Crystal analysis was negative and histopathologic examination noted connective tissue with extensive calcifications, degeneration, multiple foci of necrosis, giant cell reaction, and chronic inflammatory cells, consistent with the clinical diagnosis of hydroxyapatite deposition disease.

At the 1-week post-surgical follow-up, the patient described significant improvement in symptoms, in particular decreased pain. Physical examination was notable for stiffness in the fingers upon flexion and extension as well as decreased sensation to light touch in the median nerve distribution; however, these findings both resolved at the two week follow-up appointment. The patient was performing tasks of daily living without any concern, something which was not possible prior to surgical intervention.

Further reading:

Mass like calcific peri arthritis in the wrist: a rare case presenting as acute carpal tunnel syndrome and requiring surgical intervention

Michal Krolikowski, Christina R. Vargas, Kyle J. Chepla, David DiLorenzo

Skeletal Radiology (2022) 51:1883–1888

https://doi.org/10.1007/s00256-022-04003-x