Radiographic evaluation of idiopathic clubfeet undergoing Ponseti treatment.
BACKGROUND
The Ponseti method for treatment of idiopathic clubfeet involves the use of serial casts, percutaneous Achilles tenotomy in most cases, and bracing with an abduction orthosis to prevent relapse. Although Ponseti recommended evaluation of the infant clubfoot strictly by palpation, many orthopaedic surgeons still rely on radiographs for decision-making during treatment. The aim of this study was to document with radiographs the effect of percutaneous Achilles tenotomy as described by Ponseti.


METHODS
We conducted a study of idiopathic clubfeet treated, at two centers, with the Ponseti method, including percutaneous Achilles tenotomy. Cast treatment was started within three weeks after birth, and radiographs were made before and after the tenotomy. Lateral radiographs with the foot in maximal dorsiflexion at the ankle were made for all patients, and anteroposterior radiographs of the foot were made at one center. The lateral tibiocalcaneal angle, the anteroposterior talocalcaneal angle, and the lateral talocalcaneal angle were measured on the radiographs. Foot dorsiflexion at the ankle was evaluated clinically. The results from both centers were evaluated separately and in combination.


RESULTS
Lateral dorsiflexion radiographs that showed the foot and ankle were evaluated for eighty-seven clubfeet, and anteroposterior radiographs that showed the foot were evaluated for sixty-five clubfeet. The mean improvement in the lateral tibiocalcaneal angle after the tenotomy was 16.9 degrees . The mean change in the anteroposterior talocalcaneal angle was 2.1 degrees , and the mean change in the lateral talocalcaneal angle change was 1.4 degrees . The mean increase in clinically measured dorsiflexion after the tenotomy (in sixty-five feet) was 15.1 degrees . Only the lateral tibiocalcaneal angle and dorsiflexion as measured clinically changed significantly after the Achilles tenotomy (p < 0.05). When the results at each center were analyzed separately, they were found to be nearly identical.


CONCLUSIONS
The increase in the lateral tibiocalcaneal angle after Achilles tenotomy is essentially the same as the increase in ankle dorsiflexion seen on clinical examination. The anteroposterior and lateral talocalcaneal angles are not influenced significantly by the tenotomy. Radiographs confirmed that the additional dorsiflexion obtained from the percutaneous Achilles tenotomy is true dorsiflexion occurring in the ankle and hindfoot and not in the midfoot.


METHODS
Therapeutic Level IV.
Radler
Christof
C
Department of Pediatric Orthopaedics, Orthopaedic Hospital Speising-Vienna, Speisingerstrasse 109, 1130 Vienna, Austria. christof.radler@chello.at
Manner
Hans Michael
HM
Suda
Renata
R
Burghardt
Rolf
R
Herzenberg
John E
JE
Ganger
Rudulf
R
Grill
Franz
F
D000125:Achilles Tendon / Q000601:surgery; D002370:Casts, Surgical; D003025:Clubfoot / Q000000981:diagnostic imaging* / Q000601:surgery / Q000628:therapy*; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011446:Prospective Studies; D011859:Radiography; D013380:Subtalar Joint / Q000000981:diagnostic imaging