Page 69 - Manual of Equine Field Surgery

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Mid Metacarpal-Metatarsal Tendon Laceration Repair 65

limb i11 fetlock flexion. Disadvantages of the tra, excessive granulation tissue, stringhalt gait,

Kimzey splint include prolonged immobilization and fetlock contracture if the limb is chronically

with the distal limb in flexion and the need flexed because of pain or inadequate extensor

to keep the limb from bearing weight during tendon function. Wound infection, dehiscence,

bandage changes. A full limb cast extending to the sequestrum formation, and excessive granulation

proximal tibia will decrease strain on the superfi- tissue can be managed by local debridement

cial digital flexor tendon during repair by pre- and wound therapy. Stringhalt development is

venting hock flexion, but generally, the risk of uncommonly seen after wounds i11 the proximal

complications with a full limb cast is not worth dorsal metatarsal region and may require surgery

the benefit when repairing superficial digital flexor for treatment.15 Distal limb contracture can be

tendon lacerations in the metatarsal region. prevented by monitoring for adequate use of the

lower limb and splinting as needed.

Extensor Tendon Lacerations Complications of flexor tendon lacerations

include dehiscence, wound infection, tendon

In the early phases of extensor tendon healing, a degeneration secondary to infection, inadequate

distal limb splint is recommended to support the repair strength, vascular compromise to the lower

digit iI1 extension. Often, the support of a bandage limb, cast complications, adhesions, contracture,

is sufficient to prevent flexion, as some digital and contralateral limb laminitis. Dehiscence and

extension is due to momentum as the limb swings wound complications are managed by debride-

forward. If primary repair is performed, cast or ment and second intention healing. Inadequate

splint support should be provided for a minimum repair strength is best prevented and managed by

of 4 weeks. adequate limb immobilization and a gradual

decrease in limb support. No direct treatment is

Contralateral Limb Support available for vascular compromise. Cast compli-

cations are common but can be minimized by

Support should be provided for the opposite limb careful daily monitoring of the cast and cast

to decrease the risk of contralateral limb lameness, changes as indicated. Contracture is a complex

reduce edema, and elevate the contralateral limb problem resulting from prolonged immobiliza-

to a similar height as the casted limb. A support tion or pain and healing with excessive surround-

bandage and foot elevation are often applied to ing scar tissue. Flexor tendon lacerations in

the contralateral limb." In cases of severe injury, nonsheathed areas are less likely to have this

support to the contralateral limb is essential to complication, ai1d a gradually increasing exercise

decrease the chances of contralateral limb lamini- program improves most cases. Contralateral limb

tis. This can be provided iI1 the form of frog and laminitis is a severe complication. Appropriate

caudal support, heel elevation, and decreased support of the contralateral limb and early aggres-

breakover. Commercial shoes are available and sive treatment for the primary problem can min-

work well for this purpose (Redden Modified imize its occurrence. Appropriate treatment for

Ultimate, Nanric Inc., Versailles, Ky.).
contralateral limb larninitis .includes corrective

shoeing, deep bedding, stall rest, analgesics and,

EXPECTED OUTCOME ideally, resolution of the primary problem.

With optimal treatme11t, riding soundness occurs

in approximately 75°/o of extensor tendon lacera- ALTERNATIVE PROCEDURES

tions and SOo/o of flexor tendon Iacerations.Y'"

Return to significant athletic activity has been Annular ligament desmotomy may be indicated

reported in 23°/o to 50% of flexor tendon lacera- in some cases if superficial or deep digital

tions'v" and 71 o/o of extensor tendon lacerations." flexor tendon swelling is impeded by the annular

ligament. Typically, this is performed several

weeks or even months after the tendon injury. A

COMPLICATIONS limited case report suggests that annular ligament

desmotorny within 1 to 3 days after acute super-

Complications of extensor tendon lacerations ficial tendon rupture in racehorses may be

include wound infection, dehiscence, bone seques- beneficial. 16