Historical Overview
- Pisotriquetral (PT) arthritis can be caused by acute trauma, chronic instability or degenerative changes and typically manifests as pain at the hypothenar eminence.1
- Because the joint space is difficult to appreciate on radiographs and because patients often experience a vague pain at the volar-ulnar side of the wrist unrelated to trauma, PT arthritis is frequently missed on initial presentation.1,2
- A clinical examination of the wrist that includes the PT shear test is recommended to help improve the efficiency of this diagnosis.2
Description
- The PT shear test offers a qualitative evaluation of the PT joint that can be used to determine if PT arthritis and/or instability is present.
Pathophysiology
- Injury to the pisiform’s soft tissue attachments can lead to pain around the pisiform and hypothenar area and may result in instability of the PT joint and subsequent arthritis.3
- Osteoarthritis (OA) of the PT joint can be a normal stage in aging or it may occur after a fracture, from chronic repetitive trauma in sports, from rheumatoid arthritis, or may be aggravated after carpal tunnel release.2
- PT OA has also been found to be more prevalent in patients with scapholunate advanced collapse (SLAC) arthritis and dorsal intercalated segment instability (DISI).1
- Injury to the PT joint may be masked by more severe concomitant trauma to the wrist or hand, by repetitive indirect trauma or chronic overuse of sharp pronation-supination.1
Instructions4,5
- Obtain an accurate and complete patient history that includes an injury description if applicable.
- Place your thumb over the patient’s pisiform.
- Apply a dorsally directed pressure along with a circular grinding motion over the triquetrum.
- It is crucial to perform this test before assessing the lunotriquetral joint to avoid pain overlapping.
Related Signs and Tests
- PT arthritis differential diagnosis/related conditions:2,3
- Flexor carpi ulnaris (FCU) enthesopathy
- Pisiform fracture
- PT instability
- FCU contracture
- Hypothenar eminence pain
- Ulnar-sided wrist pain
- PT OA has been found to have a high prevalence in the older population and should therefore always be considered in the differential diagnosis for any ulnar-sided wrist pain.2
Diagnostic Performance Characteristics
- When no injury is present, the pisiform can be easily moved from side to side when the hand is relaxed.
- The stability of the pisiform is achieved by the attachment of several structures such as the FCU tendon—which continues as the pisometacarpal and the pisohamate ligament—and the extensor and flexor retinaculum. The PT joint is surrounded by a loose but strong joint capsule, which allows great mobility.2