Species: Canine | Classification: Diseases
- Cause: developmental malformation of the plantar or palmar sesamoid bones. May arise from multiple centers of ossification. Included under the general heading sesamoid disease in some texts.
- Signs: generally asymptomatic: usually incidental finding on radiography of the pes. More commonly found in the manus.
- Diagnosis: radiography. The sesamoid can be bipartite or multipartite.
- Treatment: if lame: rest and analgesia.
- Prognosis: good.
- Generally incidental finding on radiographs of the pes or manus.
- Occasionally displace causing pain on direct palpation and on flexion of the digits.
- Incidental finding when radiographed for another reason, so identified at any age.
- Assumed to be developmental, so probably occurs at stage of ossification of the sesamoid bones.
- If problems arise they often resolve with rest and analgesia.
- Two possible mechanisms suggested:
- Multiple centers of ossification that failed to unite; or
- Incomplete ossification of cartilage template.
- Sesamoid bones 2 and 7 most commonly affected, numbering medial to lateral. This is thought to be from pressure from the overlying flexor tendons during hyperextension as the metacarpo/metatarso-phalangeal joints 2 and 5 are slightly outwardly rotated.
- Developmental disorder, detailed pathogenesis unknown.
- Sesamoid bones located in tendon of insertion of the interosseous muscles at the metacarpo-phalangeal joints.
- Multiple centers of ossification during development may result in multipartite or bipartite sesamoid bone formation.
- Incomplete ossification of a cartilage template would also be a possible etiology.
- Restriction of vascular foramina in sesamoids 2 and 7 was found in dogs with sesamoid disease and not in clinically normal dogs.
- There is an over-representation in the right manus of the racing Greyhound suggesting a traumatic component.
- Usually asymptomatic.
- May manifest as pain on manipulation of the foot.
- Incidental finding on radiography, generally no lameness.
- Occasionally displaced causing discomfort and pain on direct palpation.
- See radiography of the manus Radiography: carpus and forefoot and pes Radiography: tarsus and hindfoot.
- Differentiate from fractures radiographically:
- Differentiate from degenerative disease radiographically:
- Degenerative disease has pain on palpation, joint swelling or thickening, calcified periarticular bodies and osteophytosis.
Initial Symptomatic Treatment
- No treatment in most cases.
- If painful, rest and anti-inflammatory treatment Analgesia: NSAID in the acute stage resolves most cases.
- Chronic painful cases, consider surgical removal of the painful sesamoid bone.
- If acutely painful, radiography to monitor any secondary degenerative change development.
- Conservative management: monitor lameness related to pain on direct palpation → should resolve in 4-6 weeks.
- Asymptomatic: no further monitoring or treatment needed.
Expected Response to Treatment
- If painful, surgical excision indicated if lameness persists after conservative management.
- In the long term surgical treatment has been shown to be no better than conservative management.
- Incidental finding on survey radiographs: no treatment needed - no further monitoring required.
Reasons for Treatment Failure
- Recent references from PubMed and VetMedResource.
- Harasen G (2009) Sesamoid disease. Can Vet J 50 (10), 1095 PubMed.
- Daniel A, Read R A & Cake M A (2008) Vascular foramina of the metacarpophalangeal sesamoid bones of Greyhounds and their relationship to sesamoid disease. Am J Vet Res 69 (6), 716-721 PubMed.
- Vaughan L C & France C (1986) Abnormalities of the volar and plantar sesamoid bones in Rottweilers. JSAP 27 (9), 551-8 VetMedResource.
- Bennett D & Kelly D F (1985) Sesamoid disease as a cause of lameness in young dogs. JSAP 26 (10), 567-79 VetMedResource.
- Bateman J K (1959) Fractured sesamoids in the greyhound. Vet Rec 71, 101.
Other sources of information
- Robins G M & Read R A (1998)diseases of the sesamoid bones.In:Canine Sports Medicine and Surgery.Bloomberg M S, Dee J F & Taylor R A (eds). Saunders W B Company, Philadelphia, pp 255-264.
- Robins G E & Read R A (1993)diseases of the sesamoid bones.In:Disease mechanisms in small animal surgery.pp 1094.