Equis ISSN 2398-2977

Bone: subchondral cysts

Contributor(s): Jessica A Kidd-Millar, Jessica A Kidd, Carl Kirker-Head

Introduction

  • Cause: trauma, osteoarthritis, OCD or infection.
  • Signs: lameness +/- joint effusion.
  • Diagnosis: intra-articular anesthesia, radiography, scintigraphy, computed tomography, MRI.
  • Treatment: rest, systemic or articular anti-inflammatories and chondroprotectants, surgical debridement +/- bone graft or osteochondral graft (mosaicplasty. Antibiosis if infection is involved.
  • Prognosis: dependent on location and size of cyst.
  • Commonly seen in equine bones.
  • Predominantly a condition of younger horses.
  • Does not always cause lameness.
  • Can be articular or non-articular; most cysts which cause lameness are articular.

Pathogenesis

Etiology

Pathophysiology

  • OCD   Bone: osteochondrosis  :
    • Instead of flaps of cartilage forming, the articular cartilage infolds.
    • Infolded cartilage becomes necrotic and repair is not possible.
    • Pain (and lameness) may be due to pressure of synovial fluid within the cyst, subchondral bone pain or synovitis caused by contents of the cyst released into the joint.
    • Lesions frequently develop in areas of maximal weight-bearing.
    • Can be created experimentally in predilection sites by focal full thickness cartilage defects.
  • Joint trauma causing a focal full thickness cartilage defect.
  • Osteoarthritis causing full thickness cartilage defect(s).
  • Occasionally associated with a focal infectious process.
  • Often bilateral.

Timecourse

  • Not known what the time period is between development of the cyst and when clinical signs appear, but is probably related to the location of the cyst, underlying etiology, and the use of the horse.

Diagnosis

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Treatment

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Prevention

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Outcomes

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Beccar Varela A M, Patipa L A & Eggleston R B (2014)Subchondral bone cyst of the apical portion of the proximal sesamoid bone as a cause of severe lameness in a Warmblood filly.Equine Vet Educe26(3), 126-131 VetMedResource.
  • Greet T (2014)The first recorded subchondral cyst-like lesion of a proximal sesamoid bone.Equine Vet Educ26(3), 132-133 VetMedResource.
  • Mair T & Sherlock C (2011)Osseous cyst-like lesions/subchondral bone cysts of the phalanges.Equine Vet Educ23(4), 191-204 VetMedResource.
  • Helms Boone L & Peroni J (2009)Corticosteroid intralesional injection of subchondral bone cysts.Equine Vet Educ21(12), 638-639 Wiley Online Library.
  • Del Chicca F, Kuemmerle J M, Ossent P, Nitzl D & Fuerst A (2008)Use of computed tomography to evaluate a fracture associated with a subchondral pedal bone cyst in a horse.Equine Vet Educ20(10), 515-519 VetMedResource.
  • Goodrich L R & McIlwraith C W (2008)Subchondral bone cysts - not always an easy diagnosis.Equine Vet Educ20(10), 521-524 Wiley Online Library.
  • Wallis T W, Goodrich L R, McIlwraith C W, Frisbie D D, Hendrickson D A, Trotter G W, Baxter G M & Kawcak C E (2008)Arthroscopic injection of corticosteroids into the fibrous tissue of subchondral cystic lesions of the medial femoral condyle in horses: A retrospective study of 52 cases (2001-2006).Equine Vet J40(5), 461-467 PubMed.
  • Arnold C E, Chaffin M K, Honnas C M, Walker M A & Heite W K (2008)Diagnosis and surgical management of a subchondral bone cyst within the intermediate tubercle of the humerus in a horse.Equine Vet Educ20(6), 310-315 VetMedResource.
  • Jacquet S, Audigie F & Denoix J M (2007)Ultrasonographic diagnosis of subchondral bone cysts in the medial femoral condyle in horses.Equine Vet Educ19(1), 47-50 Wiley Online Library.
  • Changoor Aet al(2006)Mapping of donor and recipient site properties for osteochondral graft reconstruction of subchondral cystic lesions in the equine stifle joint.Equine Vet J38(4), 330-336 PubMed.
  • Kay A T (2006)An acute subchondral cystic lesion of the equine shoulder causing lameness.Equine Vet Educ18(6), 316-319 VetMedResource.
  • Smith M Aet al(2005)Effect of age at presentation on outcome following arthroscopic debridement of subchondral cystic lesions of the medial femoral condyle: 85 horses (1993-2003).Equine Vet J37(2), 175-180 PubMed.
  • Bodo Get al(2004)Autologous osteochondral grafting (mosaic arthroplasty) for treatment of subchondral cystic lesions in the equine stifle and fetlock joints.Vet Surg33(6), 588-596 PubMed.
  • Garcia-Lopez J M & Kirker-Head C A (2004)Occult subchondral osseous cyst-like lesions of the equine tarsocrural joint.Vet Surg33(5), 557-564 PubMed.
  • Textor J Aet al(2001)Subchondral cystic lesions of the proximal extremity of the tibia in horses: 12 cases (1983-2000). JAVMA218(3), 408-413 PubMed.

Other sources of information

  • McIlwraith W & Trotter G (1996)Joint Disease in the Horse.W B Saunders. pp 384-396.


ADDED