- Discussion:
- this a distal "Step Cut" metatarsal osteotomy that displaces metatarsal head
laterally in order to correct hallux valgus deformity and metatasus adductus;
- Mitchell procedure is carried out more proximally than
Chevron Osteotomy,
&
can correct more severe deformities than Chevron;
- this procedure is applicable to moderate to severe deformities of
intermetatarsal angle and hallux valgus;
- Surgical Technique:
- dorsomedial incision is carried down to the joint capsule;
- dorsal and plantar skin flap is created, with care being taken to
avoid the cutaneous nerves;
- distally based flap is then created from the medial joint capsule in order to
expose Medial Eminence;
-
medial eminence is removed in line with the medial aspect of the
metatarsal shaft;
- transverse osteotomy:
- is performed thru metatarsal neck, just proximal to level of sesamoids,
however, lateral 3 mm of metatarsal cortex is left uncut;
- lateral cortex is then cut proximal to first cut;
- this cut creates a step off in the distal fragment;
- distal fragment is then displaced laterally by width of step off and is placed
into a slight degree of plantar flexion to accommodate for the degree of
shortening that has been created by removing the section of bone;
- greater the deformity the larger the need for more lateral displacement;
- osteotomy site is then secured, either with a suture or a pin;
- medial joint capsule is plicated in order to align MP joint;
- Complications:
- controlling the osteotomy site in the Mitchell procedure may be difficult and
dorsal displacement may occur;
- avascular necrosis of the metatarsal head may occur if excessive stripping
of tissue has been carried out;
- shortening of 1st metatarsal & transfer metatarsalgia to second metatarsal.
- this is compensated for by plantar flexion of distal fragment at time of surgery;
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Mitchell's osteotomy using internal fixation and early mobilisation.
The risks and benefits of distal first metatarsal osteotomies.
The Mitchell Procedure for the Treatment of Adolescent Hallux Valgus.
A Long-Term Study.
Mitchell's osteotomy using internal fixation and early mobilisation.
Mitchell's osteotomy using internal fixation and early mobilisation.
