- Congruent Joint:
- if there is no lateral subluxation, then the joint is congruent;
- hallux valgus may be the result of lateral deviation of articular surface rather than subluxation of proximal phalanx on metatarsal head;
- if joint is congruent, proximal phalanx can't be rolled around on metatarsal head to correct
hallux valgus lesion;
- therefore, to obtain correction extra-articular procedures are required so that the articular orientation is not changed;
-
extra-articular procedures include:
-
Akin Procedure;
-
Chevron;
-
Mitchell Bunion Procedure
-
Proximal MT Osteotomy:
-
Silver Procedure:
- intra-articular procedures such as the
McBride Procedure are specifically contraindicated w/ a congruent joint;
- these will lead to Hallux stiffness;
- Incongruent Joint:
- if lateral subluxation of proximal phalanx on metatarsal head is present, then joint is incongruent, meaning that proximal phalanx
can be rolled medially on metatarsal head to achieve correction of deformity;
- in this case, a distal soft tissue procedure that realigns MPJ such as the
McBride Procedure can be used;
- if the hallux valgus angle is < 30 & intermetatarsal angle is < 15 deg, then distal soft tissue procedure w/ proximal metatarsal osteotomy, is indicated;
- some authors may choose to perform a
chevron or Mitchell procedure, instead of a proximal metatarsal osteotomy;
- however, if HVA is > 30 & IM angle is > 15 deg, then usually
Chevron procedure cannot result in satisfactory correction;
- some consider
chevron contra-indicated w/ incongruent joint;
- when
hallux valgus angle is > 40 deg and / or IM angle is > 20 deg,
Arthrodesis, gives best result;
