Osseous cyst-like lesions/subchondral bone cysts of the phalanges

Abstract

Summary In the horse, the phalanges are the second most common location for the occurrence of osseous cyst‐like lesions (OCLLs) after the medial femoral condyle of the stifle. Phalangeal OCLLs occur in a variety of locations, most of which are adjacent to, if not communicating with, a joint. The aetiology of these lesions is considered to be multifactorial by most authors. Horses with OCLLs demonstrate lameness of varying severity. Diagnostic analgesia should be used to localise the lameness. After localisation of the lameness, standard radiographic views of the isolated area should be performed. The radiographic characteristics of OCLLs are dependent on the stage of development of the OCLL; OCLLs may first be identified as a small lucent flattening or depression in the articular surface; however, they may progress to a circular, oval or conical single or multi chambered radiolucency within the bone. There may be a rim of radiodense sclerosis around the lucency. Diagnosis of some OCLLs may only be achieved using nonstandard radiographic views or may require advanced diagnostic imaging modalities such as computed tomography or magnetic resonance imaging. Treatment of phalangeal cysts may be conservative or surgical. Surgical treatment options generally aim to prevent cyst enlargement and promote filling of the lesion with osseous material. Depending on the cyst, this can be performed arthroscopically or via an extra‐articular approach. Occasionally, the severity of proximal interphalangeal joint OCLLs warrants surgical arthrodesis. Overall the prognosis for return to performance for horses with OCLLs ranges from 30–90% but is dependent on the breed, age and intended use of the horse, surface area of weightbearing cartilage affected, concurrent osteoarthritis within the joint and treatment administered.

Magnetic resonance and radiographic diagnosis of osseous resorption of the flexor surface of the distal phalanx in the horse

“…tumour necrosis factor‐alpha [TNF‐α]) associated with the soft tissues lesions in the adjacent DSIL and the DDFT . This supports the hypothesis that insertional desmopathy or tendonopathy can induce osseous resorptive lesions . The involvement of both the DSIL and DDFT seen histopathologically is not only consistent with the location of the osseous resorptive lesions identified on MR but also provides further evidence that these structures often respond to stress placed upon the foot as a single functional unit .…”

Effect of recombinant human bone morphogenetic protein 2 (rhBMP-2) on equine bone formation: A preliminary in vitro and in vivo evaluation

“…Various pathogenic processes have been implicated in the occurrence of SCLs, with trauma being the likely cause in mature horses (Sherlock and Mair 2011) and osteochondrosis in juvenile horses (Verschooten and De Moor 1982). In the cases described herein, a developmental aetiology was suspected based on the young age and the bilateral occurrence in two of the three horses affected, and lack of any history of trauma (Verschooten and De Moor 1982).…”

“…Overall, the prognosis for return to performance for horses with phalangeal SCLs ranges from 30 -90 %, but is largely dependent on the age, treatment regime, location of the SCL, and concurrent osteoarthritis (Sherlock and Mair 2011). Smith et al (2005) have suggested that older horses, and those with pre-existing osteoarthritis, have a significantly poorer prognosis following surgical debridement of femoral SCLs, with only 35 % of horses older than 3 years returning to soundness after debridement.…”

Subchondral bone cyst of the apical portion of the proximal sesamoid bone as a cause of severe lameness in aWarmblood filly

“…), the talus (Montgomery and Juzwiak ) and the phalanges (Story and Bramlage ; Smith et al . ; Sherlock and Mair ).…”

“…). Subchondral bone cysts show marked variation in size and shape; they may be shallow or deep (>10 mm) and may be domed, conical or spherical in shape (Sherlock and Mair ). Grossly, these cysts have a fibrous lining and contain fibrous tissue, with or without synovial gelatinous material.…”