FOOT AND ANKLE SURGERY
From the 7th Biennial Canadian Orthopaedic Foot and Ankle Symposium
| SURGICAL MANAGEMENT OF CLAW TOE DEFORMATIONS —Timothy R. Daniels, MD, Associate Professor,
Department of Surgery, Division of Orthopaedic Surgery, University of Toronto Faculty of Medicine, Toronto,
ON
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| Epidemiology: one of most common foot deformities; incidence 2% to 20%; begins insidiously, usually with age;
deformity ranges from mild and passively correctable to severe and fixed
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| Function of toes: total weight-bearing surface of forefoot increased by toes; toes contact ground for 75% of stance
phase; myth that toes not important in weight distribution (scientific data prove importance); balance surrounding
toes—intrinsic muscles help to flex metatarsophalangeal (MTP) joint and to extend distal interphalangeal (DIP)
joint and proximal interphalangeal (PIP) joint; normal relationship of intrinsic muscles with center of rotation of
metatarsal head paramount (if relationship changes, whole dynamic of toe function changes)
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| Claw toe deformity (intrinsic minus deformity): interosseae dorsal to center of rotation; intrinsic muscles no
longer flexors of MTP joint (extension of MTP joint); extensor hood oriented in plane where it can no longer extend
PIP and DIP joints; long flexors and extensors take over; flexion at PIP joint; flexion or extension at DIP joint
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| Metatarsal head protection (from ground contact): fat pad; plantar fascia (broad insertion into septi of fat
pad); flexor tendons; plantar plate (many believe displacement of plantar plate that creates exposed metatarsal head
to create metatarsalgia)
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| Stability of MTP joint: plantar plate (30% of stability); collateral ligaments (50% of stability); surrounding soft
tissues (20%); proper positioning, insertion, and orientation of collateral ligament and plantar plate essential to dorsal
and plantar stability of MTP joint
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| Etiology of claw toe deformity: shoe wear (high heel with narrow toe box creates buckling effect on toes); patients
with long second ray predisposed to having problems with second and third toes, particularly if improper
shoes worn; history of trauma; rheumatoid arthritis; neuromuscular disease; Charcot-Marie-Tooth (CMT) disease;
diabetes; compartment syndrome; checkrein phenomenon following tibial fracture (scarring of muscle to callous of
fracture acting as checkrein); “claw toe” and “hammer toe” used interchangeably
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| Other deformities: intrinsic positive deformity—usually neuromuscular disease; flexion at MTP joint; hyperextension
at PIP joint; mallet toe—isolated flexion at DIP joint
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| Presentation: toes that deviate in transverse plane usually do so in medial direction (particularly second toe); symptoms
caused by phalanges pushing metatarsal head into floor; plantar plate strongly attached to base of proximal
phalanx, weakly attached to neck, and translates forward with proximal phalanx and fat pad; windlass mechanism
dysfunction; prominent metatarsal head with callous formation (dorsal and tip of toe) and metatarsalgia
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| Clinical evaluation: palpate for pulses (important); perform push-up test (push up on metatarsal head or just proximal
to it, and assess correctability of deformity at MTP joint) in office and operating room (OR); assess hindfoot
and midfoot for deformities; assess for muscle power (particularly in pes cavus deformity; eversion strength); look
for plantar callosities; determine whether room present for toe to be corrected to fall into; anteroposterior (AP) and
lateral x-rays, oblique films if worried about arthritis; AP and lateral films of hindfoot if deformity seen; look for
pes cavus; assess for abducted forefoot; look for medial subluxation or dislocation of joint; look for associated hallux
valgus deformity; look for osteoarthritis
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| Nonsurgical management: often very successful (especially in synovitis of second MTP joint); many people do
not need operations, just support through period of inflammation (3-6 mo); deformity then dealt with if causing
pain; off-loading metatarsal head—key in nonsurgical management; correct shoe wear (rigid shank; forefoot
rocker)
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| Surgical correction: soft tissue contracture release; bony resection if release of soft tissue contractures not sufficient
to correct deformity; flexor tenotomy (in nondiabetic patient); sequence in OR—flexor tenotomy (rigid deformities;
medial or lateral translation of toe); extensor lengthening; release of collateral ligaments off proximal
phalanx; push-up test; if no reduction, release collateral ligaments off metatarsal head; repeat push-up test; if no reduction,
consider shortening osteotomy; Weil osteotomy—speaker feels procedure revolutionized management of
claw toes; case—perform ”V” incision dorsally to avoid progressive deformity if wound contracts; expose capsule;
lengthen extensor tendons; release collateral ligaments; Weil osteotomy (blade parallel to plantar aspect of foot;
start on top of metatarsal head in articular surface); let head fall into place; excise overhanging bone; push head in
medial direction towards plantar plate; pin; problem with Weil osteotomy—intrinsic muscles stay dorsal to center
of rotation; can get dorsal subluxation of toe
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| JOINT PRESERVATION OPTIONS FOR ANKLE ARTHRITIS —Alistair S. E. Younger, MD, Instructor, Department
of Orthopaedics, University of British Columbia Faculty of Medicine, Vancouver
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| Indications: younger patients with posttraumatic deformities or ankle instability; patients who can have clear understanding
of goals of treatment (avoidance of complication of ankle fusion in young patients and secondary arthritic
changes with time; higher level of function of joint); patients who can understand outcomes (realistic
expectations; possibility of residual pain; possibility of need for revision; length of recovery time); ankle arthroscopy
possibly required to assess whether joint salvageable
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| Arthroscopic debridement: choice way of debridement; synovium debrided to assess joint; some capsule removal
possibly necessary; initial assessment done with wet field; dry scope used to remove bone spurs; final corner
removed with curette and trimmed with synovator; removal of osteophytes may not only produce symptom relief,
but prevents degenerative change in cartilage; predictions—visualizing unstable cartilage indicates ankle not salvageable
in future and possibility of ankle fusion; technique—important to get into gutters on both sides when performing
open or closed arthroscopy; debridement anteriorly, posteriorly, or both, depending on site of pain;
posterior debridement done as open procedure (difficult with scope); indications for open debridement—posterior
lesions; extensive anterior lesions; ligament sectioning possibly needed for debridement (repair at end of procedure)
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| Osteotomy: debridement and osteotomy often go hand in hand (need to clean out ankle joint when doing osteotomy);
tibial osteotomies give best correction of deformities in ankle joint (best chance of off-loading area of overload);
fibular osteotomies of value with previous fibula fracture with overload of lateral side of ankle joint or
syndesmosis disruption; calcaneal osteotomies potentially of value, but not as powerful as tibial osteotomies;
indications—patient’s ability to understand goals of procedure; degree of functional limitation of ankle and mechanical
pain; goals—preservation of ankle joint for future; studies—AP and lateral x-rays of joint to avoid missing
area of joint space narrowing; AP and lateral x-rays of tibia if malalignment present; computed tomography
(CT) and magnetic resonance imaging (MRI) valuable to determine extent of joint damage, but not as good as arthroscopy;
arthroscopy also allows for assessment of cartilage surfaces and planning of procedure; options—
medial or lateral and opening or closing wedge; blade plate for closing wedge osteotomies; compliant nonsmoking
patient for opening wedge osteotomies; tibial osteotomy technique—anterior approach; place K-wire along long
axis of tibia, pointing at knee; place K-wire across tibia, perpendicular to long axis on AP and lateral views to determine
angle of proximal cut; on distal end, put K-wire parallel to ankle joint on AP view and parallel to ankle on
lateral view to determine angle of distal cut; tendon balance potentially necessary; consider ligament repair; outcome
more dependent on correct choice of patient than on technical ability in OR
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| Distraction arthroplasty: procedure indicated in end-stage arthritis in young patient; complex procedure;
procedure—distract until joint gap at 1 cm; frame left on for 3 mo; recovery time uncertain and causes significant
issues; paper from Belgium showed mild improvement in range of motion and pain
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| Case of syndesmosis instability: fibula laterally displaced, short, and malrotated; fibular osteotomy to lengthen
and allow fibula to load-share on outside of talus; reconstruction of syndesmosis ligaments
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| Review: patient selection for joint salvage critical (realistic outcomes); outcomes unknown; dependable procedures
—ankle arthroscopy to assess cartilage and debridement; osteotomies of calcaneus, fibula, and tibia; debridement
(open or arthroscopic); distraction arthroplasty not as dependable
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| WHEN AN ANKLE SPRAIN IS NOT AN ANKLE SPRAIN: WHAT ELSE CAN GO WRONG WITH INVERSION
INJURIES —David B. Thordarson, MD, Professor and Vice Chair, and Chief, Foot and Ankle Surgery, Department
of Orthopaedic Surgery, Keck School of Medicine, University of Southern California, Los Angeles
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| Lateral process fractures (talus): “snowboarder’s ankle”; mechanism—avulsion due to inversion injury; impaction
due to eversion injury (more likely); presentation—history of twisting injury to ankle during sporting activity
or pain after snowboarding on lateral side of ankle; physical examination—difficult to discern from acute
ankle sprain with similar swelling and ecchymosis; need to follow up at 3 wk if tenderness and swelling still
present; look for tenderness towards tip of fibula; radiographic evaluation—difficult to see on initial x-ray; CT if
findings questionable and high index of suspicion for fracture; natural process—difficult to determine because often
diagnosed in chronic setting; nonoperative treatment—can treat as ankle sprain with boot or ankle cast and 4
wk of immobilization; high incidence of persistent pain; operative treatment—surgical excision for comminuted
fracture (good results); surgical treatment indicated for noncomminuted fracture with displaced large bone fragment;
unusual to find these injuries in isolation
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| Anterior process fractures (calcaneus): usually delayed diagnosis and treatment; acutely, patients have discrete
tenderness over anterior process, even if whole ankle swollen; mechanism—avulsion-type injury (most common;
sprain ankle and pull bone off at ligament attachment); impaction force injury (eversion); inversion injuries more
common than eversion injuries; radiographic evaluation—subtle; fracture visualized on lateral x-ray; oblique
view of hindfoot usually shows piece of bone; CT indicated if large fragment present or diagnosis in question (need
saggital cuts); nonoperative treatment—majority of injuries small, so nonoperative treatment option; majority do
not heal with bone, but become asymptomatic; bone excision at later time if necessary; operative treatment—piece
of bone 1 cm or visibly displaced
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| Peroneal tendon dislocation/subluxation: acute true dislocation of tendon should be treated acutely; subacute,
tendons subluxing (chronic problem); mechanism—plantar flexion inversion injury stretches superior peroneal retinaculum
(SPR) and anterior talofibular ligament (ATFL); SPR possibly completely avulsed off back of fibula or
stretched (subluxation problem); peroneus brevis becomes traumatized with subluxation; physical examination—
find swelling and ecchymosis with complete avulsion; elicit dislocation with resisted dorsiflexion eversion stress
(feel tendon snapping over bone); manually reduce tendon with thumb if feel dislocation (chronically dislocated);
nonoperative treatment—for true acute dislocation, usually fails; brace acute dislocation while waiting for surgery;
operative treatment—tendon damage possible during procedure as tendon often sits over fibula during incision;
soft tissue repair one option (run risk of failure if nothing done with bone); important to augment normal SPR
to reduce risk for recurrence; bony procedure usually done; longitudinal tear not unusual and should be debrided;
tendon excision if tendon destroyed; other options—if peroneal tendons dislocated, take calcaneofibular (CFL) insertion
out of calcaneus bone, lift off small piece of bone, and place peroneal tendons under; residual pain possible;
bony procedure technique—drill through tip of fibula and soften up bone; impact with bone tamp; repair SPR;
results—15 patients treated with this procedure, no tendon relocations observed; 3 patients with significant residual
pain (1 patient had inflammatory synovitis; 1 on workers’ compensation; 1 patient with peroneal tendon scarring)
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| Summary: inversion injuries of ankle lead to ankle sprain 90% to 95% of time; most common injury presenting to
emergency department
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Educational Objectives
| The goal of this program is to provide the listener with information on claw toe deformity, options for ankle joint
preservation in ankle arthritis, and identification of injury and management of ankles when the injury is not an ankle
sprain. After hearing and assimilating this program, the clinician will be better able to:
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 | 1. Describe claw toe deformity and the examination of a patient with claw toe deformity.
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| 2. Discuss the management of a person with a claw toe deformity.
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| 3. Discuss the indications and procedures in ankle joint preservation.
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| 4. Describe the ankle injuries that are not ankle sprains.
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| 5. Evaluate a patient with an ankle injury.
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Suggested Reading
Benthien RA, Myerson MS: Supramalleolar osteotomy for ankle deformity and arthritis. Foot Ankle Clin 9:475,
2004; Claisse PJ, et al: Effect of orthotic therapy on claw toe loading: results of significance testing at pressure
sensor units. J Am Podiatr Med Assoc 94:246, 2004; Gehrmann RM, et al: Athletes’ ankle injuries: diagnosis and
management. Am J Orthop 34:551, 2005; Porter D, et al: Peroneal tendon subluxation in athletes: fibular groove
deepening and retinacular reconstruction. Foot Ankle Int 26:436, 2005; Selmani E, et al: Current concepts review:
peroneal tendon disorders. Foot Ankle Int 27:221, 2006; Sora MC, et al: Evaluation of the ankle syndesmosis: a
plastination slices study. Clin Anat 17:513, 2004; Tanaka Y, et al: Low tibial osteotomy for varus-type osteoarthritis
of the ankle. J Bone Joint Surg Br 88:909, 2006; Valderrabano V, et al: Snowboarder’s talus fracture: treatment
outcome of 20 case after 3.5 years. Am J Sports Med 33:871, 2005; Vlahovich AT, et al: An unusual fracture
of the talus in a snowboarder. J Orthop Trauma 19:498, 2005; Warnock KM, et al: Calculation of the opening
wedge for a low tibial osteotomy. Foot Ankle Int 25:778, 2004.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. The following
has been disclosed: Dr. Thordarson is a consultant for Air Depuy. Dr. Younger is a consultant for Zimmer and receives
research support from Bio Mimetrics.
Drs. Daniels, Younger, and Thordarson were recorded at the 7th Biennial Canadian Orthopaedic Foot and Ankle
Symposium, held April 8-9, 2006, in Toronto, ON, and cosponsored by the Canadian Orthopaedic Foot and Ankle Society
and the Division of Orthopaedic Surgery, Department of Surgery, Universiry of Toronto. The Audio-Digest
Foundation thanks the speakers and the sponsors for their cooperation in the production of this program.
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