Scarf Osteotomy - operative indications, Hallux

When assessing a hallux valgus for operative correction both the first ray and also the lesser rays need consideration.
The Hallux:
Assessment prior to a scarf osteotomy is based upon balancing history, clinical and radiographic findings.
Deformity (clinical and radiographic):
Be clear at which levels the deformities lie and correct appropriately. The increased inter-metatarsal angle and hallux valgus angle can be appropriately corrected with a metatarsal osteotomy and capsular plication. Associated pronation of the hallux and a hallux interphalangeus will require an intercurrent Akin osteotomy.
Range of movement:
Location of pain and when (history):
Pure bunion pain is from the medial eminence and predominantly when in shoes).
If more dorsal or deep seated pain, irrespective of shoe wear and in particular if significantly restricting function (which bunions less commonly do) assume inter-current OA is present. Whether this means the surgical procedure needs to be changed to a corrective fusion depends upon the severity of the pain and radiographic appearance (and if your patient allows for on table decision). This is an unusual scenario and more often if OA is present its symptoms are less significant and can be managed with a debridement and microfracture at the time of scarf osteotomy.