Catastrophic complication following injection and extracorporeal shock wave therapy of a medial femoral condyle subchondral cystic lesion in a 14 year old Arabian mare

Abstract

This report describes fibrous cyst lining injection and extracorporeal shock wave therapy (ESWT) of a medial femoral condyle (MFC) subchondral cystic lesion (SCL) resulting in catastrophic MFC fracture in an Arabian mare. The mare was presented for evaluation of a severe hind limb lameness of approximately 4 months duration. On presentation, a non-weight bearing lameness of the left hind limb with severe effusion and soft tissue swelling of the stifle region was noted. Radiographic evaluation of the stifle revealed a large SCL of the MFC with associated osteoarthritis. Arthroscopic guided intra-lesional injection of the SCL with corticosteroids and autologous bone marrow concentrate was performed followed by ESWT of the MFC. The mare was discharged walking comfortably 48-hours postoperatively. An acute increase in lameness was noted 14 days post-operatively. Imaging revealed catastrophic fracture of the left MFC. Possible mechanisms leading to failure of the MFC secondary to the described treatment are discussed.

Complete fractures through osseous cyst‐like lesions of the proximal phalanx in three horses

“…The OCLLs of the proximal phalanx in this case series show very different characteristics to the cases with fractured cystic lesions mentioned in the introduction (Ball et al, 2020;Fuggazola et al, 2014;Moser et al, 2017). OCLLs of the P1 are much smaller than those reported in humans.…”

“…Only three cases of fractures associated with preexisting cysts in horses have been presented to date (Ball et al., 2020; Fuggazola et al., 2014; Moser et al., 2017). In two cases, a fracture through an existing large osseous bone cyst in the distal phalanx (P3) and a collapse of a large medial femoral condyle (MFC) SCL, humane euthanasia was elected (Ball et al., 2020; Moser et al., 2017).…”

“…Only three cases of fractures associated with preexisting cysts in horses have been presented to date (Ball et al., 2020; Fuggazola et al., 2014; Moser et al., 2017). In two cases, a fracture through an existing large osseous bone cyst in the distal phalanx (P3) and a collapse of a large medial femoral condyle (MFC) SCL, humane euthanasia was elected (Ball et al., 2020; Moser et al., 2017). The one case which resulted in a favourable outcome was reported to be an 18‐month‐old filly with a large unicameral bone cyst in the greater tubercle of the right front humerus (Fuggazola et al., 2014).…”