Distal humerus revised

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  • 1.Fractures of the Distal HumerusGregory J. Della Rocca, MD, PhDOriginal authors: Jeffrey J. Stephany, MD and Gregory J. Schmeling, MD; March 2004Second author: Laura S. Phieffer, MD; Revised January 2006Curent author: Gregory J. Della Rocca, MD, PhD; Revised October 2010

2. Functional Anatomy Hinged joint withdistal humeralsingle axis of rotationtriangle(trochlear axis) Trochlea is centerpoint with a lateral andmedial column 3. Functional Anatomy The distal humerusangles forward Lateral positioningduring ORIFfacilitatesreconstruction of thisangle 4. Surgical Anatomy The trochlear axis compared to longitudinalaxis is 94-98 degrees in valgus The trochlear axis is 3-8 degrees externallyrotated The intramedullary canal ends 2-3 cmabove the olecranon fossa 5. Surgical Anatomy Medial and lateralcolumns diverge fromhumeral shaft at 45degree angle The columns are theimportant structuresfor support of thedistal humeraltriangle 6. Mechanism of Injury The fracture patternmay be related to theposition of elbowflexion when the loadis applied 7. Evaluation Physical exam Soft tissue envelope Vascular status Radial and ulnar pulses Neurologic status Radial nerve - most commonly injured 14 cm proximal to the lateral epicondyle 20 cm proximal to the medial epicondyle Median nerve - rarely injured Ulnar nerve 8. Evaluation Radiographic exam Anterior-posterior and lateral radiographs Traction views may be helpful to evaluate intra-articular extension and for pre-operativeplanning (creates a partial reduction vialigamentotaxis) Traction removes overlap CT scan helpful in selected cases Comminuted capitellum or trochlea Orientation of CT cut planes can be confusing 9. OTA Classification Follows AO Long Bone System Humerus (#1X-XX), distal segment (#X3-XX) = 13-XX 3 Main Types Extra-articular fracture (13-AX) Partial articular fracture (13-BX) Complete articular fracture (13-CX) Each broad category further subdivided into9 specific fracture types 10. OTA Classification Humerus, distal segment (13) Types Extra-articular fracture (13-A) Partial articular fracture (13-B) Complete articular fracture (13-C) 11. OTA Classification Humerus, distal segment (13) Types Extra-articular fracture (13-A) Partial articular fracture (13-B) Complete articular fracture (13-C) 12. OTA Classification Humerus, distal segment (13) Types Extra-articular fracture (13-A) Partial articular fracture (13-B) Complete articular fracture (13-C) 13. Summary - Classifications A good classification should do the following: Describe injury Direct treatment Describe prognosis Be useful for research Have good inter-observer reliability Have good intra-observer reliability Most classification schemes fail in some ofthese categories 14. Treatment Principles1. Anatomic articular reduction2. Stable internal fixation of the articular surface3. Restoration of articular axial alignment4. Stable internal fixation of the articular segment to the metaphysis and diaphysis5. Early range of motion of the elbow 15. Treatment: Open Fracture Urgent I&D Definitive reduction and internal fixation Primary closure acceptable in somecircumstances Temporary external fixation across elbow ifdefinitive fixation not possible Definitive fixation at repeat evaluation Antibiotic therapy Repeat evaluation in OR as necessary untilsoft tissue closure 16. Fixation Implants determined by fracture pattern Extra-articular fractures may be stabilized byone or two contoured plates Locked vs. nonlocked based upon bone quality, working length for fixation, surgeon preference Intra-articular fractures Dual plates most often used in 1 of 2 configurations 90-90: medial and posterolateral Medial and lateral plating 17. Dual plating configurations Schemitsch et al (1994) J Orthop Trauma8:468 Tested 2 different plate designs in 5 differentconfigurations Distal humeral osteotomy with and withoutbone contact Conclusions: For stable fixation the plates should be placed on the separate columns but not necessarily at 90 degrees to each other 18. Dual plating configurations Jacobson et al (1997) J South Orthop Assoc6:241. Biomechanical testing of five constructs All were stiffer in the coronal plane than thesagittal plane Strongest construct medial reconstruction plate with posterolateraldynamic compression plate 19. Dual plating configurations Korner et al (2004) J Orthop Trauma 18:286 Biomechanically compared double-plateosteosynthesis using conventional reconstructionplates and locking compression plates Conclusions Biomechanical behavior depends more on plate configuration than plate type. Advantages of locking plates were only significant if compared with dorsal plate application techniques (not 90/90) 20. Other Potential Surgical Options Total elbow arthroplasty Comminuted intra-articular fracture in the elderly Promotes immediate ROM Usually limited by poor remaining bone stock Bag of bones technique Rarely indicated if at all Cast or cast / brace Indicated for completely non-displaced, stable fractures 21. Fixation in elderly patients John et al (1993) Helv100% 90%Chir Acta 60:219 80% 70% 49 patients (75-90 yrs)60% 41/49 Type C 50% 40% Conclusions30% 20% No increase in failure10% of fixation, nonunion, 0% nor ulnar nerve palsy Result Age not a contra- very good good fair/poor indication for ORIF 22. Total elbow arthroplasty Cobb and Morrey100%(1997) JBJS-A 79:82690%80% 20 patients 70% avg age 72 yrs 60%50% TEA for distal humeral40%fracture30%20% Conclusion10% TEA is viable treatment 0% option in elderly patientResult with distal humeralExcellent Good Fair/poor fracture 23. ORIF vs. elbow arthroplasty Frankle et al (2003) J Orthop Trauma 17:473 Comparision of ORIF vs. TEA for intra-articular distalhumerus fxs (type C2 or C3) in women >65yo Retrospective review of 24 patients Outcomes ORIF: 4 excellent, 4 good, 1 fair, 3 poor TEA: 11 excellent, 1 good Conclusions: TEA is a viable treatment option for distalintra-articular humerus fxs in women >65yo, particularlytrue for women with assoc comorbidities such asosteoporosis, RA, and conditions requiring the use ofsystemic steriods 24. Surgical Treatment Lateral decubitus position Prone positioning possible Supine position difficult Arm hanging over a post Sterile tourniquet ifdesired Midline posterior incision Exposure ? 25. Exposures Reduction influences outcome in articularfractures Exposure affects ability to achievereduction Exposure influences outcome! Choose the exposure that fits the fracturepattern 26. Surgical exposures Triceps splitting Allows exposure of shaft to olecranon fossa Extra-articular olecranon osteotomy Allows adequate exposure of the distal humerusbut inadequate exposure of the articular surface 27. Surgical exposures Intra-articular olecranon osteotomy Types Transverse Indicated for intra-articular Group IIfractures Technically easier to do 30% incidence of nonunion (Gainor et al,(1995) J South Orthop Assoc 4:263) Olecranon implant removal may be necessary due to irritation 28. Surgical exposures Intra-articular olecranon osteotomy Types Chevron Indicated for intra-articular Group IIfractures Technically more difficult More stable Olecranon implant removal may be necessary due to irritation 29. Osteotomy Fixation Options Tension band technique Dorsal plating Single screw 30. Osteotomy Fixation Single screw technique Large screw +/- washer Beware of the bow of the proximal ulna, which may cause a malreduction of the tip of the olecranon if a long screw is used. Eccentric placement ofscrew may be helpful Hak and Golladay, JAAOS, 8:266-75, 2000 31. Osteotomy Fixation Single screw technique Large screw +/- washer BEWARE: large-diameter screw threads may engage ulnar diaphysis (small medullary canal) prior to full seating of screw head Bite of screw may be strongwithout full compression Careful scrutiny of lateralradiograph important to assurefull seating of screw head Hak and Golladay, JAAOS, 8:266-75, 2000 32. Osteotomy Fixation Single screwtechnique Long screw may bebeneficial for adequatefixation Short screw may loosen or toggle with contraction of triceps against olecranon segmentHak and Golladay, JAAOS, 8:266-75, 2000 33. Osteotomy Fixation Tension band technique K-wires or screw with figure-of-8 wire Easy to place (?) May be less stable than independent lag screwor plate Implant irritation K-wires try to engage anterior ulnarcortex near coronoid base Mullett et al (2000) Injury 31:427, Prayson et al (1997) J Orthop Trauma 11:565 34. Engage anterior ulnarcortex here with wires toimprove fixationstability/strengthTension band wire Length of screw may be important to resist toggling and loss of reductionTension band screw 35. Osteotomy Fixation Dorsal plating Low profile periarticularimplants now available Axial screw through plate Good results after platefixation Hewin et al (2007) J Orthop Trauma 21:58 Tejwani et al (2002) Bull Hosp Jt Dis 61:27 36. Chevron Osteotomy Expose olecranon and mobilize ulnar nerve If using screw/TBW fixation, pre-drill andtap for screw placement down the ulnacanal Small, thin oscillating saw used to cut 95%of the osteotomy Osteotome used to crack and complete it 37. Chevron osteotomy Coles et al (2006) J Orthop Trauma 20:164 70 chevron osteotomies All fixed with screw plus tension band or withplate-and-screw construct 67 with adequate follow-up: all healed 2 required revision fixation prior to healing 18 of 61 with sufficient follow-up requiredimplant removal 38. Surgical exposure Triceps-sparing postero-medial approach(Byran-Morrey Approach) Midline incision Ulnar nerve identified and mobilized Medial edge of triceps and distal forearm fasciaelevated as single unit off olecranon andreflected laterally Resection of extra-articular tip of olecranon 39. Bryan-MorreyApproach 40. Surgical exposure Medial and lateral exposures triceps sparing Triceps-sparing Good for extra-articular fractures and some simpleintra-articular fractures (OTA type

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