This is the most common condition of the 5th metatarsal. Also known as a bunionette deformity. It is a bony prominence located on the outside of the foot also known as the dorsallateral or lateral aspect of the 5th metatarsal head region.
1.Irritation with shoes causing pain, redness, and swelling.
2.lesions or calluses or hyperkeratosis along the lateral side.
1.5th Metatarsal is the most flexible of the metatarsals and independent axis of motion.
2.Faulty development of the transverse metatarsal ligament during embryonic growth.
3. Malinsertion of a muscle called the adductor hallucis.
4. Continued pressure of a shoe on the outside of the foot.
5. Sitting crossed leg for long periods of time, hence the name “Tailors”.
4th and 5th intermetatarsal angle
Bisecting the 4th and 5th metatarsal, but Fallat and Buckholz system bisects the 4th, but uses the medial surface of the proximal 5th metatarsal.
Normal: 6.22 degrees
Abnormal: 9.62 degrees
Lateral Deviation angle
Formed by the line bisecting the 5th metatarsal head and neck and a line from the medial surface of the proximal 5th metatarsal.
Normal: 2.64 degrees
Abnormal: 4.84-8.00 degrees
Location of maximum deformity
Formed by lines intersecting the bisection of the 5th metatarsal base and the distal metatarsal head and neck.
1.shoe modifications and padding
2. NSAIDs (non-steriodal antiinflamatory drugs)
3.Local injections of corticosteriod
4. Physical therapy such as ultrasound or iontophoresis or phonopheresis
5. Orthotics to alleviate pressure points.
1. Exostectomy: removing the bony prominence without internal fixation or hardware.
2. Arthroplasty: removing the distal end of the metatarsal head. This is mainly used for geratric population or patients that have very poor bone density or not very active.
3. Metatarsal osteotomy (Most common)
With Exostectomy and Arthroplasty the post operative care will only be about 2-4 weeks in a post operative walking shoe, then return to normal daily activites.
With osteotomies then it depends which procedure is performed. Simple distal ostetomies will be about 4-6 weeks in a walking cast boot then gradually in a post op shoe or regular shoe.