FLEXOR TENDON INJURIES OF THE HANDMichael Zlowodzki MDPGY-3 ResidentUniversity of MinnesotaDepartment of Orthopaedic SurgeryOUTLNEAnatomyClinical assessmentTreatment depending on Zone of injuryTendon healing biologyRepair techniques Post-op motion protocolsDelayed graftingANATOMYDSOrigin (2 muscle bellies) Medial epicondyle Radial shaftTendons arise from separate muscle bundlesACT INDEPENDANTLYDPOrigin: ulna & interosseous membraneDP: Common muscle origin for several tendonsSIMULTANEOUS FLEXION OF MULTIPLE DIGITSFDPDSDPPLLumbricals origin from radial side of DPCAMPER's CHASMADS divides and passes around the DP tendon, the two portions of the DS reunite at "Camper's ChiasmaTENDON SHEETSPreserve A2 and A4 puIIey to prevent bowstringing. NOTE: There is aPreserve A2 and A4 puIIey to prevent bowstringing. NOTE: There is a mistake in this diagram: The C1 puIIey is DISTAL to the A2 puIIey! mistake in this diagram: The C1 puIIey is DISTAL to the A2 puIIey!PULLEYSTENDON EXCURSION- 9 cm of flexor tendon excursion with wrist and digital flexion- only 2.5 cm of excursion is required for full digital flexion with the wrist stabilized in neutral positionTENDON EXCURSONMP motion = no flexor tendon excursion1.5 mm of excursion per 10 degrees of joint motion for DP (DP) and PP (DS, DP)LOOD SUPPLYSegmental branches of digital arteries which enter the tendon through: vincula osseous insertionsSynovial fluid diffusion 'INCULAECLINICAL EXAMFDS: CIinicaI ExamTENODESS EECTPassive extension of the wrist does not produce the normal "tenodesis flexion of the fingers if flexors are injuredFDS: CIinicaI ExamFDP: CIinicaI ExamDP RUPTURENo active DP motion (present passive DP motion)ONESREPAIR ALL COMPLETE TEARS AT ALL LE'ELS!ONE 1 INJURIES:Jersey FingerERSEY NGERERSEY NGERLEDDY CLASSCATONType 1: Retraction into palmType 2: Retraction to PP levelType 3: ony avulsion (tendon attached)Type 4: ony avulsion (tendon attached not attached to bony fragment)REPAIR WITHIN 7-10 DAYSTYPES O REPARDirect repair:if laceration is more than 1 cm from DP insertionTendon advancement: if the laceration is less then 1 cm from insertion. TENDON ADVANCEMENTUTTON STRONGER THAN SUTURE ANCHORSTendon Advancement Previously advocated for zone 1 repairs, as moving the repair site out of the sheath was felt to decrease adhesion formation Disadvantages Shortening of flexor system Contracture Quadriga effectQUADRGA EECTf DP tendon advanced too distallyEntire muscle bells gets pulled distallyTendon excursion of DP of other digits is limitedLoss of grip strengthONE 2 INJURIESZONE 2 NURESZone 2: Deep and superficial flexor gliding inside tendon sheetsTraditionally "No man's land: Stiffness after repairNURY: Tendons retractONE 2:PARTIAL LACERATIONSPartial lacerationNo repair if 40% of the tendon intactPotential complications:TriggeringTendon entrapment Eval for the risk of triggering; debride if necessarydorsal block splinting for 6 to 8 weeks N=15 patients with zone partial flexor tendon lacerations of the width of the tendon (Avg. 71%) Conservative treatment: Dorsal blocking splint with wrist in 10 of flexion mmediate guarded active ROM Splint removed @ 4w No restriction @ 6w excellent results in 93% and good in 7%hy not fix a partial laceration when you staring at it in the OR anyway?ecause the dissection necessary to fix it might cause too much scarring, which might outweigh the benefitONE 2:COMPLETE LACERATIONSMORE STRANDS: STRONGER & STIFFER REPAIRUltimate Strength and Repair TechniqueProportional to number of strands 6 and 8 strand repairs strongest Steep learning curve ncreased bulk and resistance to glide ncreased tendon handling and adhesion formation May not be necessary for forces of early active motion4-STRAND REPAIR ADEQUATE STRENGTH WITHOUT COMPLEXITY OF 6-8 STRANDSProximal Tendon Retrievalix DP and DS or just DP?hy?ecause the blood supply to the DP tendon is jeopardized if the DS is not also fixed (due to the vinculae anatomy)Personal communication: Dr. James House)FIX FDP AND FDS!COMPLCATONSStiffnessRe-ruptureTenolysis may be required in an estimated 18% to 25% of patients No earlier than 3 months after repair f no ROM improvement for 1-2 monthsONE 3 INJURIESLumbrical muscle bellies usually are not sutured because this can increase the tension of these muscles and result in a "lumbrical plus finger (paradoxical proximal interphalangeal extension on attempted active finger flexion). ONE 4 INJURIESZONE 4: Carpal TunnelTENDON HEALINGlexor tendon healingIntrinsic heaIing: occurs without direct blood flow to the tendon Extrinsic heaIing: occurs by proliferation of fibroblasts from the peripheral epitenon adhesions occur and limit tendon glidingPHASES O TENDON HEALNG1.nflammatory (0-5 days) : strength of the repair is reliant on the strength of the suture itself2.ibroblastic (5-28 days) : or so-called collagen-producing phase3.Remodelling (28 days - 4months)TENDON WEAKEST @ 10-14 DAYSRUNNER INCISIONSUTURE TECHNIQUESesslerModified essler(1 suture)Advantage: Only one node inside the repair site. Easier to use a monofilament suture like a 4.0 Proline to re-approximate tendon edges.essler-Tajima(2 sutures)SUTURE MATERALNon-absorbableMost authors prefer a synthetic braided 3.0 or 4.0 suture, usually of polyester material (Mersilene, Tycron, Tevdek) However, monofilament sutures like nylon and wire are also used (e.g. Proline)Additional running, circumferential 5-0 or 6-0 nylon is used oftenIN: Interference with heaIingOUT: Interference with tendon gIiding SUTURE NOT LOCATONSUTURE NOT LOCATONnots outside superior in one in vitro study (Aoki)Statistically significant increase in tensile strength at 6 wks with knots insidetechnique in canine model (Pruitt)FEW STUDIES - NO CONSENSUSSHEAT REPARAdvantages arrier to extrinsic adhesion formation More rapid return of synovial nutritionDisadvantages Technically difficult ncreased foreign material at repair site May narrow sheath and restrict glideNO CLEAR AD'ANTAGE ESTALISHEDPOST-OP REHAHSTORCALunnel (1918) Postoperative immobilization Active motion beginning at 3 wks postop. Suboptimal results by today's standards mproved suture material/technique as well as postoperative rehabilitation protocolsSTIFFNESSRUPTUREToo much motionTo little motionRUPTURESTIFFNESPOST-OP PROTOCOLS1. leinert: Active extension, passive flexion by rubber bands2. Duran: Controlled Passive Motion Methods3. Strickland: Early active ROMGOAL: FULL ACTI'E ROM @ 10-12 weeksleinert ProtocolDuran protocolDURAN PROTOCOLDorsal Splint in 20 deg wrist flexionNo rubber bandsPassive flexionDesigned in response to notion 3-5mm of tendon gliding sufficient to prevent restrictive adhesionsRehabilitationStrickland (1980s-1990s)Uses a 4 strand repair with epitendinous suture Dorsal blocking splint with wrist at 20 deg of flexion Supervised active ROM starts POD #3 Unsupervised AROM at 4 weeksRarely used, because it requires a pretty extensive "bulky repair to allow for early active ROM. A lot of surgeons thinks that too much suture material may be problematic for tendon healingCHLDREN Usually not able to reliably participate in rehabilitation programsNo benefit to early mobilization in patients under 16 yearsmmobilization >4 wks may lead to poorer outcomesRole for otox?DELAYED RECONSTRUCTIONSingle Stage Tendon Grafting:ndicationsSegmental tendon lossDelay in definitive repair (>3-6 weeks)Need ull PROM Competent pulleysSingle Stage Tendon GraftingZone 2 njuriesGraft donors Palmaris longus Plantaris Long toe extensors (DS) (EP) (EDM)Two Stage ReconstructionndicationsExtensive soft tissue scarring Crush injuries Associated fractures, nerve injuriesLoss of significant portion of pulley systemTwo Stage Reconstruction: Stage 1Excision of tendon remnants Hunter rod then placed through pulley system and fixed distally Reconstruct pulleys as needed if implant bowstringsTwo Stage Reconstruction: Stage 2mplant removal and tendon graft insertion DS transfer from adjacent digit describedPostop Early controlled motion x 3 wks, then slow progression to active motionTwo Stage ReconstructionPatient selection Motivated Absence of neurovascular injury Good passive joint motionalance benefits of two additional procedures in an already traumatized digit with amputation/arthrodesisCOMPLICATIONSCOMPLCATONS oint contracture Adhesions Rupture owstringing nfectionMY PREFERENCE(ased on this review and the subsequent feedback)MY PREERENCE ix DS and DP asap - ideally within 7 days of injury3.0 Proline modified essler stitch (one node inside)f tendon is big enough use another 4.0 Proline modified essler stitch Additional 5.0 Proline running epitendinous sutureleinert or Duran post-op protocolOTE QuestionAnswerOTE QuestionOTE magingAnswerTHANK YOUSpeciaI thanks to DanieI Marek MD for borrowing some of the sIides