Hallux valgus UG lecture

1. Hallux Valgus D r Dhananjaya sabat MS, DNB, MNAMS Assistant Professor Orthopedics MAMC & STC, New delhi

2. INTRODUCTION Lateral deviation of the great toe and medial deviation of the first metatarsal Progressive subluxation of the first metatarsophalangeal (MTP) joint Static deformity due to valgus angulation of the distal articular surface of the first metatarsal or the proximal phalangeal articular surface.

3. Pathophysiology No single cause Intrinsic conditions: 1. Metatarsus primus varus : congenital / heriditary ( AD), 2. Pes planus , 3. ligamentous laxity, 4. neromuscular Footwear: 15 times increased incidence female sex 4 th -6 th decade age Rheumatoid arthritis

4. Anatomy Four groups that encircle the first MTP joint Extensor hallucis longus and brevis Flexor hallucis longus and brevis Abductor Adductor Deforming Musculature 1. Abductor Hallucis - Inserts in the plantar aspect of the proximal phalanx -Can draw the phalanx medial and push metatarsal head lateral 2. Adductor Hallucis - 2 origins -common tendon to plantar aspect of proximal phalanx and lateral aspect of plantar plate/ sesamoid complex

5. Anatomy Plantar Plate 2 seasmoids incorporated into tendons of FHB Plantar Plate formed by tendons of Adductor Hallucis, Abductor Hallucis, FHL and Joint Capsule

6. Fig 8

7. Clinical Presentation PAIN over the medial eminence (Bunion). Pressure from footwear is the most frequent cause of this discomfort. Bursal inflammation Irritation of the skin Breakdown of the skin may be noted. Bunion consists of: Bony exostosis / prominence of the metatarsal head Overlying subcutaneous bursa Hyperkeratosis of dermis

8. Pronated Toe Fig 6

9. Physical Examination Skin : calluses, areas of redness Sites of pain Magnitude of the hallux valgus deformity Pronation of the great toe Motion of 1st MTP joint- increased or decreased, Pain or crepitus , or both, with motion of the MTP joint Metatarsocuneiform joint for hypermobility Examiner grasps the first metatarsal with the thumb and index finger and pushes it in a plantar lateral-to- dorsomedial direction; mobility > 9 mm represents hypermobility Pes planus deformity , Contracture of the Achilles tendon Mobility and structure of foot in general Gait analysis

10. Radiographic Examination Weightbearing AP & Lateral Axial ( Sesamoid ) Assess for bone and joint deformity Length and shape of 1st MT Congruent vs. Incongruent joint Osteoarthrosis Forefoot alignment is evaluated for metatarsus Adductus Hindfoot is Inspected for Pes Planus or Pes Cavus .

11. Measure Angles Hallux Valgus angle: Intersection of longitudinal axis of 1st MT and proximal phalanx. Normal < 15 Intermetatarsal angle Intersection of 1st and 2nd MT. Normal < 9 ; increased with metatarsus primus varus

12. Distal Metatarsal Articular Angle (DMMA) Defines the relationship of the distal articular surface of the 1st MT to the longitudinal axis. Quantities the magnitude of lateral slope of articular surface. With subluxation , the articular surface deviates laterally in relationship to the 1st Metatarsal. Usually < 6 . Proximal Phalangeal Articular Angle (PPAA)

13. CLASSIFICATION MILD MODERATE SEVERE Hallux valgus angle < 20° 20° to 40° > 40° 1-2 intermetatarsal angle 11° or less. 12- 15° 16° or more Subluxation of the lateral sesamoid , as measured on an AP radiograph < 50% 50% to 75% > 75% SEVERITY OF DEFORMITY

14. TREATMENT Non-operative vs. Operative All patients should be treated non-operatively first. Despite conservative measures, some patients eventually need surgical intervention.

15. Treatment NON-OPERATIVE Footwear Modification Widen toe box decrease lateral deviation of great toe decrease inflammation and pain Decrease heel height prevent forward slide of the foot Arch support may negate effects of pes planus

16. Contracture of the Achilles tendon Stretching exercises Lengthening of the Achilles tendon Thermoplastic night splints

17. Treatment SURGICAL Indications: Persistent PAIN not cosmetic complaints Progression of deformity Failure of non-operative treatment Goals: Correct all pathologic elements and yet maintain a biomechanically functional forefoot Usually will not result in a foot with normal appearance Combine soft tissue procedures with bony procedures in almost all cases.

18. Treatment SURGICAL : SOFT TISSUE PROCEDURE Distal Soft-Tissue Reconstruction Medial and lateral procedures Hallux Valgus angle <30 degrees IMA < 15 degrees High rate of recurrence if done without bony procedure Medial and lateral procedures at the same time contraindicated. Medial Procedures Tighten lax capsule advancement, plication or resection Abductor must not be detached Lateral Procedures Capsular release adductor longus release or transfer Division of transverse MT ligament risk NV bundle Medial side procedure recommended Be aware of cutaneous branch of medial plantar nerve . Lateral procedure more difficult. Neurovascular risk.

19. Treatment SURGICAL: Bony Procedures Distal MT: for IM angle 12-15 Mitchell {step cut} Wilson {Oblique} Chevron Proximal MT: for IM angle > 15 . Medial opening wedge, lateral closing wedge, cresentic or dome Phalangeal : Proximal Phalanx Osteotomy -Akin Combination osteotomies Arthrodesis of MCP jt / Keller’s excission for arthritis of MTP jt. Metatarsocunieform procedures: arthrodesis ( Lapidus ) for hypermobile first ray

20. Distal MT Osteotomy Mitchell Chevron

21. Proximal Cresenteric Osteotomy

22. Double Osteotomy Technique

23. Surgical Algorhythm HVA IMA Procedure < 40 ° < 13° to 15° modified McBride or distal chevron osteotomy < 40 ° > 13° to 15° modified McBride and proximal osteotomy >40° > 20° modified McBride and proximal osteotomy or arthrodesis

24. Complications SURGERY Recurrent deformity 20-30% Hallux Varus Pronation deformity Pain Neurologic Injury Osteonecrosis Physeal injury/arrest Nonunion/ malunion