Akin osteotomy

Described by Akin in 1925 for correction of HV, involving resection of medial promience of 1st MT head & medial wedge osteotomy of PP
Also described removal of prominence on medial aspect of base of PP, & lateral capsular release if necessary.

Indications

HV interphalangeus
Residual HV after MT correction
Asymptomatic HV causing symptomatic displacement of 2nd toe
In combination with MT procedure for HV

addition of Akin allows exact derotation of the hallux
adds improved cosmetic appearance of the toe
helps align & derotate the toe without relying on extreme capsular imbrication
this may prevent excessive pressure on MTP & lead to less pain & stiffness postop.

Contra-indications

(for Aitken alone) severe MT primus varus
Incongruous 1st MTP joint
Severe Osteoarthritis 1st MTP joint

Technique

Longitudinal medial incision over MTP joint through skin, bursa, capsule, head
Resect bunion prominence in line with medial border of foot
Extend incision distally to expose basilar portion of PP
3mm medially based wedge osteotomy in metaphyseal portion of PP within 5-7mm of joint
can correct residual pronation deformity after 1stMT osteotomy if present
Wedge closed & position maintained with 2 crossed k-wires from distal to proximal. Leave wires prominent. (or Varisation staple)
Reapproximate capsule & bursal incision
Bunion dressing maintaining corrected position
Weight bear as tolerated

Complications

perioperative

general

anaesthetic

specific

medial branch of SPN nerve damage

postoperative

early

Nonunion
Loss of position - malunion
Shortening (inevitable with closing wedge)
Infection
Neuroma

Late

Degenerative changes

recurrence of deformity

Results

Akin Alone
- Frey, Melvin Jahss,.
  - Foot & Ankle 1991
  - Followed up 45 Akin procedures, most (36/45) for asymptomatic bunions with 2nd toe symptoms, & remaining 9 for residual HV after MT surgery
  - 32/45 Excellent: no recurrence, no abutment, & no pain
  - 8/45 Good result being – no recurrence of deformity, but abutment against 2nd toe without pressure, & occasional mild pain
  - 4 fair (recurrence of deformity)
  - 1 poor (non-union at 9/12)
  - 20 technical problems in 18 feet:
    - pins not holding, <50% bone apposition, plantar or dorsal (22%incidence ? pull of EHL) angulation >10º
  - Recommended obtaining intraop xrays to check position of osteotomy
  - Degenerative changes:
    - 10pts developed mild & 2 mod degen changes in IP joint at >1yr. (none MTPjt) = radiographic findings, not Symptoms’ic
  - Average PP shortening 4mm
  - ROM: restriction at IP joint in 68%

(normal in 10/31, mildly restricted in 8, mod in 11 & severe in 2. (1/3:1/3:1/3)
restriction at MTP joint in 10% (range normal in 28/31, mild in 1, mod in 2.)

Mathematical analysis of osteotomy determined that 3mm wedge = 8º correction
5mm wedge = 16º correction., 8mm wedge = 24º corretion

Combined Chevron + Akin osteotomy for HV
- Tollison M
- Foot & Ankle International
- Aug 1997 477-481
- Retrospective review of 47pts (73 toes) average age 62, who had chevron/akin double osteotomy. (Disagreee that age >50 is C/I to Chevron with no significant pain or stiffness occurring in MTP in comparison with other bunion procedures.)
- Akin osteotomy rarely indicated as an isolated procedure in correction of HV
- More commonly used as a combination procedure with a MT osteotomy for correction of HV with MPV
- Chevron serves as major component & is used to correct widened IMA & HV. Akin osteotomy only removes about a 2mm wedge of bone & corrects any residual intraop valgus or pronation of hallux. Phalangeal osteotomy held with abs sutures securing distal periosteum to MTP capsule. (can secure with 8mm staple)

Grading of Tibial Sesamoid subluxation

Draw line up MT shaft

Grading of Tibial Sesamoid Subluxation
Grade	Description
0	sesamoid medial to line
1	>50% medial to line
2	>50% lateral to line
3	100% lateral to line

primary indication for Chevron is mild to moderate bunion deformity with HVA <30-35º & an IMTA of <15º
C/I are: moderate to severe deformity, pronation of great toe >15º, & age >50