Idiopathic ischemic necrosis of an accessory carpal bone in a dog

Abstract

Case Description—A 6-year-old neutered female mixed-breed dog was evaluated because of a 6-week history of left forelimb lameness that varied in severity. Clinical Findings—Radiography revealed expansile and lytic changes of the left accessory carpal bone (ACB). Results of histologic evaluation of ACB core biopsy specimens indicated areas of bone necrosis. The entire left ACB was excised and submitted for histologic evaluation; results confirmed a diagnosis of idiopathic ischemic necrosis. Treatment and Outcome—Left pancarpal arthrodesis was performed to treat carpal hyperextension and persistent lameness. The dog had an excellent functional outcome with no other problems related to the carpus until its death 4 years later, further decreasing suspicion that the problem was attributable to an undetected neoplasm or bacterial or fungal osteomyelitis. Clinical Relevance—The radiographic and histologic findings for the dog of this report were similar to previously reported findings for dogs with ischemic femoral head necrosis and humans with ischemic carpal (pisiform or lunate bone) necrosis. The etiology of the ischemic ACB necrosis in this dog was not determined. To the authors’ knowledge, this is the first report of a dog with idiopathic ischemic ACB necrosis. Idiopathic ischemic necrosis should be included as a differential diagnosis for dogs with lameness and destructive and expansile ACB radiographic lesions. An excellent functional outcome may be attained by means of ACB excision and pancarpal arthrodesis.

Imaging Diagnosis—radiography and Computed Tomography of Radioulnar Ischemic Necrosis in a Jack Russell Terrier

“…Ischemic necrosis of the bone may result from intraluminal obstruction (e.g., thromboembolic disorders or stasis), vascular compression (e.g., external pressure or vasospasm), or disruption of vessels (e.g., trauma). In the dog, ischemic necrosis is encountered most commonly within the epiphysis (e.g., Legg‐Calve‐Perthés), followed by small bones of the carpus (e.g., idiopathic ischemic osteonecrosis of the carpal bone and the diaphysis (e.g., RUIN). In previous reports, the exact cause of ischemic osteonecrosis is unknown.…”

Radioulnar Ischaemic Necrosis in a Dog with Concurrent Osteomyelitis and Bone Sequestration

“…1 Osteonecrosis in dogs has also been reported to occur with Legg-Calves-Perthes, idiopathic osteonecrosis of the carpal bone and maxillofacial osteonecrosis. [2][3][4] This is the first case report of concurrent haematogenous osteomyelitis and ischaemic necrosis occurring at the site of a lesion that is radiographically consistent with RUIN.…”

“…Fineneedle aspirates are minimally invasive and have been successfully used to diagnose bony lesions in both veterinary and human medicine. 2,[13][14][15][16][17] Although histopathology from a surgical biopsy could have strengthened our diagnosis, it was not performed due to the positive clinical response in the recheck interim and the difficulty of reaching the lesion.…”

Avascular Necrosis of the Intermedioradial Carpal Bone in a 6-Month-Old Dog

“…Idiopathic AVN of an accessory carpal bone has also been reported in a 6-year-old dog which was treated with excision of the accessory carpal bone and pancarpal arthrodesis. 5 Avascular necrosis of the scaphoid (intermedioradial carpal) bone in humans (Preiser's disease) is a rare pathology causing pain and swelling around the dorsoradial wrist. 6 Although it is recognized to occur following fractures of the scaphoid, 7 it is currently described as idiopathic and other proposed causes include trauma, vascular damage, corticosteroid usage, systemic disease and congenital mechanisms.…”