Outline. Extracapsular Repair !"#!"$!% COMPARISON OF SURGICAL METHODS FOR CRUCIATE DISEASE. Ursula Krotscheck, DVM DACVS Cornell University

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1 COMPARISON OF SURGICAL METHODS FOR CRUCIATE DISEASE Ursula Krotscheck, DVM DACVS Cornell University Outline! Basic concepts behind the 3 major surgical procedures! Prospective study! Expected outcomes per procedure Extracapsular Repair $%

2 Extracapsular Repair!Traditional! Fabello-tibial suture cycles! Uses nylon (monofilament)! Expect loosening! Dogs still function well Fixation Techniques!Knots! Square knots! Sliding half hitch! Self-locking knots!crimps! One person tensioning! Able to put through range of motion before committing Ethibond?! Ethibond and clamped square knots! Does not allow for restoration of physiological stifle stability! After few cycles of passive joint motion further destabilizes the joint! One of the reasons:! Clamped square knots do not allow for conservation of initial loop tension.! Clinical relevance: lateral suture stabilization using a multi strand Ethibond loop and clamped square knots should be avoided Böttcher P 2010 #%

3 Materials required! Standard surgical pack! Hohmann retractor, stifle distractor! Gross hook and spoon and Meniscal knife! Securos needle! Sterile Leader line (40, 80, 100 lb test)! Steinmann pin and hand chuck! +/- Crimping system (securos) Order of go:! Craniolateral incision from proximal patella to mid tibial tuberosity! Sharp dissection through lateral retinaculum and reflection until access to fabella! Move skin incision to medial side! Small medial arthrotomy, joint exploration, closure! Placement of lateral fabellar suture! Pass suture under cranial tibial muscle! Closure: tensor fascia, SQ, skin &%

4 Approach Approach!SQ!Lateral retinaculum! ID lateral fabella Arthrotomy! Pull skin incision to medial side! Perform standard craniomedial stifle arthrotomy '%

5 Arthrotomy! Distally to tibial plateau and proximal to patella if desired! Can be smaller arthrotomy than craniolateral! Important structures are easily accessed through medial incision! Can still use Hohman, stifle distractor, etc! Close in standard fashion when done! Let skin return to lateral side Medial Arthrotomy Evaluation of the CCL and medial meniscus Intact CCL Ruptured CCL (%

6 Arthrotomy medial meniscus!+/- Cruciate debridement!+/- Meniscal debridement! Debride if there is a tear!closure of the joint capsule Tibial Tuberosity Hole! At level of PT insertion! Exposure:! Incision along cranial border of cranial tibial muscle! Periosteal elevator to push muscle caudally on bone! Use hand chuck or drill for hole! Most common mistake:! Too distal! Too cranial! Goal:! Minimize cycling of implant Tibial Tuberosity Hole!Perpendicular to long axis of tibia!make small incision and reflect back cranial tibial muscle!%

7 Tibial Tuberosity Hole Pass Suture! Good pass AROUND fabella! Goals:! Entry point:! In valley between fabella and femur! Exit point:! Usually well distal to fabella! Fabella should move slightly when suture pulled up tensioned! Should NOT be able to feel suture! Should be able to lift up dog slightly Pass Suture! Repeat pass if:! Can feel suture either superficial or caudal/lateral to fabella! Grabbing too much soft tissue! Will loosen later! May incorporate nerve:! Sciatic! Common peroneal! Tibial )%

8 Pass Suture! Good pass AROUND fabella! If repeat too often, soft tissues will be macerated! Pass UNDER cranial tibial muscle! Come out through dissected area created for tibial tuberosity hole Pass Suture! What to do if tibial tuberosity hole not large enough to pass suture and needle?! Usually in small dogs! Equipment! Large-ish needle! 18 g or so! Large-ish suture! 0, #1 Pass Suture!Insert needle through tibial tuberosity hole! Medial to lateral *%

9 Pass Suture!Loop suture through leaderline! Pass both ends through needle Pass Suture!Remove needle!use suture loop to pull leaderline through TT hole Pass Suture! Repeat! Under patellar tendon! EXTRA- SYNOVIAL +%

10 Ta-Da!!! Now crimp or tie Crimp! Great if no surgical assistant! Most secure fixation! Allows testing of ROM before commitment Sliding Half-Hitch $,%

11 Closure! Place stifle through ROM! Minimal drawer! Minimal limitation of ROM! Close lateral retinaculum! 2-0 PDS! Close SQ! 3-0 Monocryl! Close Skin! Intradermal or skin sutures Outcome! Why this procedure works! Short term stability! Provided by the lateral suture! Decrease in instability = decrease in inflammation and increase in comfort! Long term! Stability provided by fibrous tissue created by the body! The suture will ultimately fail! Healing is a race between build up of fibrous tissue around the joint and when the suture breaks Outcome! Most animals do very well with procedure! Return to near normal function! Complications! Implant failure prior to the development of periarticular fibrosis leading to instability! Infection! Late meniscal damage! Incisional complications! Nerve damage! Tearing of the fabello-femoral ligament $$%

12 TTA TTA! Aim is to rearrange biomechanics of stifle joint and minimize/eliminate the need for the cruciate ligament Tibial Tuberosity Advancement $#%

13 Tibial Tuberosity Advancement $&%

14 Post-Operative TTA Post-Op Care and Rehab! Incisional drainage! Bandaging! Expected function Post Operative Care! Modified Robert Jones bandage! 3 layers! Ice hours post op! ROM can begin within 1 week post op (usually while still in hospital)! Recheck 2 week suture removal! Leash walks only 8 weeks! Rads if TPLO or TTA $'%

15 6/26/16 Prognosis Good to Excellent Determined by: Amount of pre-existing OA Presence of meniscal damage Surgical complications TPLO TPLO Tibial plateau leveling osteotomy Take away the need for the cruciate 15

16 So how does it do this? $!%

17 TPLO Femu r Cd Cr Tibia $)%

18 Pre-Operative Radiographs! Radiographs for OA, dx, presence of fabellae, etc! CC and lateral, including stifle and tarsus! Must include measuring bar/ball! Tibial Plateau Angle (TPA):! Describes the angle of the medial tibial plateau relative to the long axis of the tibia! The greater the TPA, the greater the tibial thrust and the resultant stress placed on the CCL! Accurate after 90 days of age Measure Radiographs A C B! A: Intercondylar eminences to center of talus! B: Medial tibial plateau (CCL insertion to caudal plateau)! C: perpendicular to A where A and B intersect Rotation Amount Saw Radius Starting TPA Rotation on amount (mm) $*%

19 Tibial Plateau Angle! All TPLOs aim to correct the TPA to ~5 degrees! Follow-up: no clinical difference in post-op TPA 0-14 degrees! New data suggests slight overcorrection to ~3 degrees Surgical Procedure! Joint:! Craniomedial approach! Arthroscopy! TPLO:! Tibial Exposure! Jig Placement (optional)! Osteotomy, rotation and temporary fixation! Plate application! Closure Arthrotomy rotomy! Remove fat pad for visualization! Evaluate cranial and caudal cruciate ligaments! Evaluate menisci for any damage! Close with absorbable suture (PDS) $+%

20 Medial approach to tibia! Extend incision over proximalmedial tibia! Reflect back caudal head of sartorius mm! Visualize medial collateral Attach jig! Functions of the jig:! Maintain medial-lateral alignment of proximal vs. distal piece of tibia! Functions as point of rotation for proximal piece! Saw template attachment Tibial Osteotomy! MUST be perpendicular in all planes! Saw should intersect caudal tibial cortex perpendicularly! MUST maintain enough tibial crest to prevent later fracture! MOST IMPORTANT PART OF PROCEDURE #,%

21 Apply TPLO Plate! All sizes from cat to giant breed! R and L Pre and Post-Op rads #$%

22 6/26/16 Prospective Study Materials and Methods Study population: Dogs with unilateral cranial cruciate rupture, >15 kg Normal radiographs of the contralateral stifle and hips Surgical intervention determined by owner Required recheck schedule: 2 weeks, 8 weeks, 6 months, 12 months Gait analysis at all visits Radiographs at 8 week visit for TPLO and TTA groups Radiographs for all at 12 month visit Materials and Methods Surgical procedure Craniomedial (TPLO, TTA) or craniolateral (ECR) approach Partial or caudal horn meniscectomy as indicated No meniscal release 22

23 Materials and Methods! Implants! Synthes locking TPLO plate! Kyon TTA implants! Monofilament nylon (80 or 100 lb test) fabellotibial suture, secured with crimps (Securos ) or self-locking knot Materials and Methods! Gait analysis! Two serial force platforms 1 embedded in a 10 m walkway! Performed at walk and trot! Minimum of 5 acceptable trials! Good paw strikes, no distractions or pulling! Controlled velocity with dual-photocell system:! Walk ( m/s)! Trot ( m/s)! Real-time processing with video and custom software /01%23%41/5067%87631%9-:;%<%=./172>?@%9A76B1%C$%BD13%C#;% -./01%23%41/5067%87631%9-:;%<%D23E72>?@% 9A76B1%C$%BD13%C#;% F67G% Time (seconds) #&%

24 6/26/16 Materials and Methods Ground reaction forces: Peak vertical force (PVF) normalized to weight (N/N) Contact time (CT) Vertical impulse (VI) - normalized to weight (N/N) Symmetry indexes calculated SI = 1 n SI = symmetry index n R k n = number of trials Lk w k k=1 R k = mean of the right (or operated) limb measurement L k = mean of the left (or unoperated) limb measurement w k = weighing factor (=1 in normal level locomotion) Materials and Methods Control population: Mean (±SD) of the population s mean SI for acceptable trials for each GRF were calculated Single session Treatment population: Mean (±SD) for acceptable trials for each GRF at each recheck time period were calculated Normal function defined as: SI of a GRF within one SD of the mean of the control population. Materials and Methods Statistical analysis: Repeated measures ANOVA/General linear model Variables: age weight sex side Statistical significance: P <0.05 tear type meniscectomy interaction between treatment and time period after surgery 24

25 Time (seconds)!"#!"$!% Materials and Methods! Pearson correlation coefficients!! All ground reaction forces at the walk and trot Rear limbs only Time (seconds) Results! 80 control dogs! 38 treated dogs! TPLO n=15! TTA n=14! ECR n=23 Results! Recheck time periods for operated group:! 1-49 days! days! days!!300 days ECR TPLO TTA #(%

26 6/26/16 Results Control (n=80) TPLO (n=15) TTA (n=14) ECR (n=23) Weight (kg) Age (yr) Sex Male Female Results Control (n=80) TPLO (n=15) TTA (n=14) ECR (n=23) Weight (kg) 30.2 ± ± ± ± 7.2 Age (yr) 3.3 ± ± ± ± 2.6 Sex Male Female Results Tear type Meniscal status TPLO (n=15) TTA (n=14) ECR (n=23) Partial Complete No meniscectomy Meniscectomy P-value

27 6/26/16 Results Reasons for case decrease: Lost to follow-up (7 TPLO, 4 TTA, 7 ECR) Meniscal tear (1 TPLO, 1 ECR) Tibial tuberosity fracture (1 TPLO) Contralateral cranial cruciate rupture (3 TTA, 3 ECR) TPLO (n=15) TTA (n=14) ECR (n=23) 2 days weeks weeks months months Results Control Population Symmetry Indexes PVF VI CT Walk 1.00 (0.050) 1.01 (0.050) 1.01 (0.031) Trot 1.00 (0.045) 1.01 (0.074) 1.02 (0.053) Continuous data reported as mean (SD) Results Repeated measures ANOVA/General linear model Variables: age weight sex side tear type meniscectomy interaction between treatment and time period after surgery 27

28 6/26/16 Results Repeated measures ANOVA/General linear model Variables: age weight sex side tear type meniscectomy interaction between treatment and time period after surgery Example 1.2 Symmetry Index = Significant difference between treatment groups R-square = X F-value = X P-value = X TPLO ECR TTA Control 0 days 1-49 days days days >300 days Time Period after surgery Results,, and indicate no significant difference between TPLO, ECR, and TTA group and the control group, respectively 28

29 Results!,, and indicate no significant difference between TPLO, ECR, and TTA group and the control group, respectively Results!,, and indicate no significant difference between TPLO, ECR, and TTA group and the control group, respectively!! Post-op TTA PTA CT = 91.9 degrees No correlation between cage size or post-op PTA CT and function Walk PVF TPLO ECR TTA Control days 1-49 days days days 300 days and over #+%

30 Walk VI TPLO ECR TTA Control B 0 days 1-49 days days days 300 days and over Trot PVF TPLO ECR TTA Control days 1-49 days days days 300 days and over Trot VI TPLO ECR TTA Control B 0 days 1-49 days days days 300 days and over &,%

31 Discussion! TPLO achieves normal function at walk and trot 6-12 months after surgery! TTA has most rapid recovery in early post-operative stage at the walk, achieves normal function at walk 12 months after surgery, but not at trot! Function did not correlate with amount of advancement! Function did not correlate with post-op PTA CT! ECR never achieves normal function Limitations! Small sample size! All R 2 are! 0.63! Not randomized! Owner determined Complication Rates - TPLO! % overall!5% Re-op rate!bilateral simultaneous surgery? &$%

32 Avulsion of Tibial Crest &#%

33 Implant Failure Implant Loosening Implant/Soft Tissue Infection &&%

34 Implant/Soft t Tissue Infection Patellar Fracture TTA Complications! 31.5% overall! 12.3% major, 19.3% minor Lafaver S. et al. Vet Surg 2007 (36) ! Subsequent meniscal tear, tibial fracture, implant failure, infection, lick granuloma, incisional trauma, and MPL! All major complications were treated and resolved, all but 2 minor complications resolved &'%

35 Tibial Fracture/Implant Failure Other Complications! Septic joint! Patellar tendon desmitis! Nerve damage! Meniscal injury/re-injury! OA progression! Injury of contralateral CCL (~54% will rupture contralateral within a year) How to Choose:! Considerations:! How strong does the implant need to be for the dog s personality?! What is the tibial plateau angle?! What is the intended use/job?! Is the caudal cruciate intact?! How quickly does the dog need to be able to use the limb?! Financial considerations &(%

36 6/26/16 Summary Pick appropriate procedure for client-patient pair Only do a procedure if you re able to deal with the complications Any Questions? 36