Plantar forefoot pressure changes after second metatarsal neck osteotomy.
BACKGROUND
The aim of this study was to evaluate plantar pressure changes after second metatarsal neck osteotomy using the Weil technique.


METHODS
Six below-knee cadaver specimens were used. Each specimen was held in a custom-built apparatus and loaded to 500 N for a period of 3 seconds. Using a computerized Musgrave pedobarograph, pressure measurements were made before and after osteotomy in both neutral and 45-degree heel rise positions. All osteotomies were made at an angle of approximately 20 degrees relative to the long axis of the metatarsal shaft. The metatarsal heads were displaced proximally by 5 mm and fixed with a single Kirschner wire.


RESULTS
After osteotomy there was an average decrease in pressure beneath the second metatarsal from 70.6 to 45.1 kPa in neutral and from 813.0 to 281.4 kPa in heel rise, representing statistically significant (p < or = 0.05) decreases of 36% and 65%, respectively. There also were significant decreases beneath the third metatarsal in both neutral (39%) and heel rise (37%), and beneath the fourth metatarsal in neutral position (28%). A significant pressure increase occurred beneath the first metatarsal in neutral (23%). No significant pressure changes occurred under the fifth metatarsal in either position.


CONCLUSIONS
Overall, our results indicated that the Weil metatarsal neck osteotomy is effective at offloading the second metatarsal head at neutral and heel rise positions.
Khalafi
Afshin
A
Orthopaedic Surgery, University of California, Davis, Sacramento, USA. afshin.khalafi@ucdmc.ucdavis.edu
Landsman
Adam S
AS
Lautenschlager
Eugene P
EP
Kelikian
Armen S
AS
D001696:Biomechanical Phenomena; D002102:Cadaver; D005545:Forefoot, Human / Q000503:physiopathology*; D006801:Humans; D008682:Metatarsal Bones / Q000601:surgery*; D010027:Osteotomy; D011312:Pressure