Front Matter

Case Study 11.1 Supination of front foot post digital amputation

Signalment: 13‐y.o. FS German Shorthaired Pointer.

History: Patient injured left thoracic limb (LTL) manus
on a hunting trip in 2008 at the age of 6 years. Over
3 years she developed pain and splaying of the second
and third digits, which was managed medically. The
second digit was amputated via metacarpophalangeal
(MCP) disarticulation when medical management
failed. Patient remained consistently lame postopera­
tively and within 6 months of the surgery the foot col­
lapsed (digital arch) and the patient was no longer able
to hunt. A surgical revision was performed with no
improvement. Client noticed the right thoracic limb
(RTL) foot collapsing (supination and digital collapse) as
well, but not as severely. Presented for options to return
to hunting, improve comfort, and protect the right tho­
racic foot from further injury.

Home environment: Single dog home, hardwood
and carpeted floors, dog door, and two steps out to
large yard.

Job: Hunting with client (waterfowl and pheasants).

Evaluation: General health: Unremarkable for age
and breed. BCS 5/9.
Conformation: WNL for breed with following excep­
tions: markedly splayed supinated digits 3‐5 LTL; mildly
splayed digits 2‐5 with minor decrease in digital arch
RTL; mild carpal valgus LTL. Mildly toed‐out stance
bilateral thoracic limbs typical of breed. In stance, LTL
positioned relatively mediad (adducted) from shoulder,
shifting total body force vector to lateral aspect of foot.
Gait: Ambulatory × 4. Grade 2/5 LTL lameness.

Clinical evaluation: Orthopedic: Appendicular exam
WNL with exception of noted splaying and supination;
mild thickening of MCP joints 2 and 5 bilaterally
except for absence of LTL 2nd digit (disarticulation at
the MCP joint; no thickening or pain associated with
the carpus).
Neurological: WNL.
Myofascial: Increased tone and myofascial sensi­
tivity of the epaxial muscles of the neck and trunk as
well as antigravity muscles of RTL (biceps brachii,
supraspinatus, triceps group, digital flexors). Reduced
flexibility of left pectoral muscles, latisimus dorsi,
and brachiocephalicus.
Biomechanical: Carpal goniometery in degrees:

Diagnostics: Radiographs of left manus including

neutral lateral, stressed lateral (carpus), antero­

posterior. Fragmented sesamoids RTL 2 and 5, LTL 5.

Degenerative changes at these joints. No abnormali­

ties associated with carpus. No evidence of sagittal

plane pathology; increased extension of right carpus

compensatory (weight shifting to  RTL) with no soft

tissue swelling noted radiographically.

Diagnosis: (1) Superficial and deep digital flexor fail­

ure with digital supination subsequent to amputation

of left second digit by MCP disarticulation. (2) Bilateral

MCP osteoarthritis secondary to chronic trauma of

active lifestyle. (3) Mild superficial and deep digital

flexor stretching/strain RTL due to compensatory over­

loading. (4) Right carpus not affected with hyperexten­

sion despite differences in midstance carpal angles

(right +38° and left +28°). Difference due to overload­

ing the RTL by compensating for the LTL.

V‐OP goals:

(1) Provide comfortable foot bed for LTL.

(2) Limit splaying of digits of LTL.

(3) Provide propulsion assist in absence of mean­

ingful palmar‐flexion function on LTL foot.

(4) Improve LTL weight bearing to limit strain on

RTL.

Case management: Rx: (1) Double‐articulating car­

pus foot orthosis with custom insole for foot seg­

ment. The carpus component is only for suspension

of the foot segment. (2) Rehabilitation for gait re‐

education, transitions, and long‐term management

of compensatory soft tissue issues.

Mechanical principle: Propulsion assist (class 2

lever).

Wearing schedule: Gradual break in over several

weeks. To be used as sport/support orthosis for heavy

activity (walks, play, hunting), but can be used all day

and off at night if needed.

Case follow‐up: Patient is comfortable in orthosis

and wears it daily. Returned to hunting both sea­

sons since device was fitted. At this time, client

reports that her age, rather than her thoracic limbs,

limits her hunting. At 18‐month recheck, no pro­

gression in RTL pathology and LTL remains stable.

<Left stance

(4 leg/3 leg)

Right stance

(4 leg/3 leg)

Left PROM

flex/ext

Right PROM

flex/ext

Left

walk*

Right

walk*

+16/+20

+7 valgus

+15/+15

+5 valgus

40/+25 55/+25 25/28/24 33/38/28

*Initial contact/midstance/terminal stance (propulsion).

(Continued)