FIBULAR & SYNDESMOSIS MALUNIONS

Transcription

1 FIBULAR & SYNDESMOSIS MALUNIONS MICHAEL P. CLARE, MD FLORIDA ORTHOPAEDIC INSTITUTE TAMPA, FL USA MORTISE INHERENTLY UNSTABLE LATERAL MALLEOLUS ACTS AS BUTTRESS / POST RESIST LATERAL TRANSLATION OF TALUS MORTISE INHERENTLY UNSTABLE POSTERIOR MALLEOLUS RESIST POSTERIOR TRANSLATION OF TALUS 1

2 MORTISE INHERENTLY UNSTABLE MEDIAL MALLEOLUS / ANTERIOR COLLICULUS SUPERFICIAL DELTOID LIGAMENT A P ROLE IN RESISTING EXTERNAL ROTATION OF TALUS MORTISE INHERENTLY UNSTABLE MEDIAL MALLEOLUS / POSTERIOR COLLICULUS DEEP DELTOID LIGAMENT A P 1 STATIC STABILIZER RESIST EXTERNAL ROTATION OF TALUS WHY IS THIS IMPORTANT? ANKLE JOINT SUBJECT ENORMOUS FORCES OVER RELATIVELY SMALL SURFACE AREA OF CONTACT TO THE BIG SHOW # 2

3 WHY IS THIS IMPORTANT? RAMSEY & HAMILTON: JBJS 58-A, MM LATERAL TRANSLATION OF TALUS: 42% REDUCTION SURFACE CONTACT AREA IN 2MM LATERAL TRANSLATION OF TALUS: 64% REDUCTION SURFACE CONTACT AREA IN DECREASED CONTACT AREA: ABNORMAL DISTRIBUTION OF JOINT STRESSES: ARTHRITIS WHY IS THIS IMPORTANT? THORDARSON, ET AL.: JBJS 79-A, 1997 FIBULAR DISPLX: 2 MM SHORTENING OR LATERAL SHIFT EXTERNAL ROTATION > 5 INCREASED CONTACT FORCES ANKLE JNT: PREDISPOSE TO ANKLE ARTHRITIS ON WHY IS THIS IMPORTANT? RAPID DETERIORATION POST-TRAUMATIC ANKLE ARTHRITIS 3

4 CORONAL PLANE ALIGNMENT PERFECT SYMMETRY BETWEEN MEDIAL & LATERAL CLEAR SPACE CORONAL PLANE ALIGNMENT FIBULAR LENGTH SHENTON S LINE TALOFIBULAR SYMMETRY DIME SIGN RESTORATION OF FIBULAR LENGTH/ROTATION IS CRITICAL TALOFIBULAR SYMMETRY LATERAL COLUMN OF TALAR BODY IN LINE WITH POSTERIOR INCISURA 4

5 INDIRECT PUSH-PULL SECURE PLATE TO DISTAL FRAGMENT CORTICAL SCREW OUTSIDE PLATE (+ 4MM) LAMINAR SPREADER BETWEEN SCREW & PLATE PROXIMAL FRAGMENT SECURED WITH CLAMP INDIRECT PUSH-PULL PLATE MUST SIT JUST ANTERIOR TO POSTEROLATERAL RIM OF DISTAL FRAGMENT TO RESTORE ROTATION TIBIAL TUBERCLE TO FOOT AXIS ROTATIONAL ALIGNMENT ALMOST ALWAYS ALIGNS WITH 2ND RAY EXCEPTION: EXTERNAL TIBIAL TORSION 5

6 FIBULA USUALLY SHORTENED &/OR EXTERNALLY ROTATED TIBIAL TUBERCLE TO FOOT AXIS OFTEN MEDIAL TO 1ST RAY TIBIAL TUBERCLE TO FOOT AXIS TALUS FOLLOWS FIBULA FIBULA EXTERNALLY ROTATED RELATIVE TO DISTAL TIBIA 6

7 STANDING XR ESSENTIAL DETERMINE ORIGINAL FX PATTERN ASSESS FIBULAR LENGTH STANDING XR ESSENTIAL LOOK FOR ASYMMETRY WITHIN MORTISE ASSESS LATERAL TALAR BODY TO INCISURA CT SCAN FOR JOINT SUBLUXATION / LARGER POSTERIOR MALLEOLAR FRAGMENTS 7

8 CT SCAN ASSESS JOINT SALVAGEABILITY BILATERAL CT SCAN USEFUL FOR SUBTLE CASES SHORT FIBULA RE-CREATE ORIGINAL FX LINE ALLOWS RESTORATION OF LENGTH & ROTATION 8

9 CASE 1 19M COLLEGE BASEBALL PLAYER INJURY SLIDING INTO 2ND BASE UNABLE TO BEAR WEIGHT INJURY FILMS: P-ER 4 ORIF DONE ELSEWHERE 9

10 4 MONTHS POST-OP "MY ANKLE IS ROLLING IN" CT SCAN 10

11 CASE 1 PURE EXTERNAL ROTATION MALUNION THRU SYNDESMOSIS FIBULAR LENGTH RESTORED SOFT TISSUE INTERPOSITION IN SYNDESMOSIS / MEDIAL CLEAR SPACE? HWR / MEDIAL ARTHROTOMY 11

12 SYNDESMOSIS DEBRIDEMENT REDUCTION CLAMP / K-WIRE REVISION FIXATION 12

13 ROTATIONAL AXIS RESTORED 2 YEARS POST REVISION ORIF CASE 2 32M / PROFESSIONAL CHEF FELL DOWN STAIRS P-ER 4 PATTERN ORIF DONE ELSEWHERE 13

14 3 MONTHS POST-OP PAIN WITH WEIGHTBEARING "MY FOOT TURNS OUTWARD" COMPENSATORY INTERNAL ROTATION OF LEG CASE 2 EXTERNAL ROTATION MALUNION OF FIBULA & SYNDESMOSIS FIBULA SHORT / EXTERNALLY ROTATED INSUFFICIENT LENGTH OF PLATE TIBIOFIBULAR SYNOSTOSIS CASE 2 HARDWARE REMOVAL SYNOSTOSIS TAKEDOWN SYNDESMOSIS DEBRIDEMENT MEDIAL CLEAR SPACE DEBRIDEMENT 14

15 CASE 2 PUSH-PULL / LAMINAR SPREADER REVISION ORIF FIBULA OPEN REDUCTION OF SYNDESMOSIS REVISION ORIF SYNDESMOSIS REVISION FIXATION CASE 3 67 YR OLD OBESE FEMALE / S/P FALL 15

16 ORIF DONE ELSEWHERE ORIF DONE ELSEWHERE (AGAIN) CASE 3 SHORTENING / EXTERNAL ROTATION MALUNION OF FIBULA & SYNDESMOSIS FIBULAR LENGTH NOT CLOSE MORTISE GROSSLY MALALIGNED INSUFFICIENT LENGTH OF PLATE 16

17 CASE 3 HARDWARE REMOVAL NONUNION MOBILIZATION MEDIAL CLEAR SPACE DEBRIDEMENT PUSH-PULL / LAMINAR SPREADER REVISION ORIF ANKLE/SYNDESMOSIS NU TAKEDOWN / REVISION ORIF 2 YEARS POST REVISION ORIF 17

18 SUMMARY LOOK CRITICALLY AT RADIOGRAPHS DETERMINE JOINT SALGAEABILITY DETERMINE ORIGINAL FX PATTERN SUMMARY ASSESS FIBULAR LENGTH ASYMMETRY OF MORTISE / TALAR BODY TO FIBULAR INCISURA TIBIAL TUBERCLE TO FOOT AXIS SUMMARY MUST STRIVE FOR PERFECT SYMMETRY OF ANKLE MORTISE RE-CREATE ORIGINAL FX LINES INDIRECT PUSH-PULL: RESTORATION OF FIBULAR LENGTH / ROTATION 18

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