Anterior Cruciate Anterior Cruciate Ligament Ligament

Reconstruction: Reconstruction: Autograft versus Autograft versus

AllograftAllograft

By: Sarah TaylorBy: Sarah TaylorEvidence Based MedicineEvidence Based Medicine

February 2009February 2009

PICO QuestionPICO Question PatientPatient: Athletic patients ages 15-30 with : Athletic patients ages 15-30 with

complete anterior cruciate ligament (ACL) complete anterior cruciate ligament (ACL) teartear

InterventionIntervention: Autograft reconstruction: Autograft reconstruction ComparisonComparison: Allograft reconstruction: Allograft reconstruction OutcomeOutcome: Fully restored knee function : Fully restored knee function

(range of motion, stability, etc.) as well as (range of motion, stability, etc.) as well as decreased morbidity (quadriceps weakness, decreased morbidity (quadriceps weakness, patellofemoral pain, loss of motion, early patellofemoral pain, loss of motion, early degenerative changes, arthrofibrosis, degenerative changes, arthrofibrosis, infection, etc.) and likelihood of revision. infection, etc.) and likelihood of revision.

EpidemiologyEpidemiology Approximately 1 in 3000 people in Approximately 1 in 3000 people in

the United States suffer ACL injuries the United States suffer ACL injuries each yeareach year

Women 4x greater risk than menWomen 4x greater risk than men 70% Sports-related70% Sports-related More than 100,000 ACL More than 100,000 ACL

reconstructions being performed reconstructions being performed annuallyannually

BiomechanicsBiomechanics The ACL functions as the primary The ACL functions as the primary

restraint to anterior translation of the restraint to anterior translation of the tibia and a secondary restraint to tibia and a secondary restraint to tibial rotation and to varus/valgus tibial rotation and to varus/valgus stressstress

Ultimate tensile load measured up to Ultimate tensile load measured up to 2160 N and stiffness of 242 N/mm2160 N and stiffness of 242 N/mm

It may tolerate strain of about 20% It may tolerate strain of about 20% before failingbefore failing

Response to InjuryResponse to Injury ACL lacks ability to regain functional ACL lacks ability to regain functional

integrity after conservative integrity after conservative treatment post-injury treatment post-injury

Therefore, if a patient wishes to Therefore, if a patient wishes to regain near-full functional stability regain near-full functional stability surgical ACL reconstruction is neededsurgical ACL reconstruction is needed

The Older method: Autograft The Older method: Autograft ReconstructionReconstruction

Currently, the most common graft choice Currently, the most common graft choice for arthroscopic ACL reconstruction is the for arthroscopic ACL reconstruction is the bone-patellar tendon-bone (BPTB) bone-patellar tendon-bone (BPTB) autograftautograft– Other sources: hamstring, semitentinosis, Other sources: hamstring, semitentinosis,

gracillis and the iliotibial band gracillis and the iliotibial band Reference of standard for restoring Reference of standard for restoring

functional knee stability with 85-95% functional knee stability with 85-95% success ratesuccess rate

Return to physical activity 6 months Return to physical activity 6 months postoperativelypostoperatively

Autograft: What’s the Autograft: What’s the problem?problem?

Often associated with significant Often associated with significant morbidity including:morbidity including:– quadriceps weaknessquadriceps weakness– patellofemoral painpatellofemoral pain– loss of motionloss of motion– early degenerative changesearly degenerative changes

Prepared bone-patellar tendon-bone autograft with marked bone-tendon junction.

Busam and Rue (2007)

What’s the Alternative?What’s the Alternative?

ACL reconstruction with allograft ACL reconstruction with allograft tissuetissue

A prepared bone-patellar tendon-bone allograft with marked bone-tendon junction.

Busam and Rue (2007)

Allograft ACL ReconstructionAllograft ACL Reconstruction

Taken from cadaversTaken from cadavers Thought to have advantage of:Thought to have advantage of:

– no donor-site morbidityno donor-site morbidity– larger predictable graft sizeslarger predictable graft sizes– low incidence of arthrofibrosislow incidence of arthrofibrosis– shorter operative timeshorter operative time

What’s the problem now?What’s the problem now?

Allograft ACL reconstruction has Allograft ACL reconstruction has been associated with complications, been associated with complications, including:including:– High costHigh cost– Slower incorporation/recoverySlower incorporation/recovery– Bacterial, viral and prion disease Bacterial, viral and prion disease

transmissiontransmission– Lower stability ratesLower stability rates

Literature AnalysisLiterature Analysis Meunier, Odensten and Good (2007) Meunier, Odensten and Good (2007)

– Performed randomized controlled trial involving 100 Performed randomized controlled trial involving 100 patients randomly allocated to primary patients randomly allocated to primary reconstruction of an ACL rupture with an autograft or reconstruction of an ACL rupture with an autograft or non-surgical treatmentnon-surgical treatment

– Upon 15-year follow-up, found that those patients Upon 15-year follow-up, found that those patients who were not treated surgically experienced who were not treated surgically experienced significantly more problems with instability, significantly more problems with instability, meniscus injuries and development of osteoarthritismeniscus injuries and development of osteoarthritis 2/3 of patients who did not initially undergo surgical repair 2/3 of patients who did not initially undergo surgical repair

ended up getting a surgical repair due to instability ended up getting a surgical repair due to instability

– Conclusion: early ACL reconstruction with an Conclusion: early ACL reconstruction with an autograft improves knee stability and decreases the autograft improves knee stability and decreases the likelihood for meniscus injury and early development likelihood for meniscus injury and early development of osteoarthritis of osteoarthritis

Literature AnalysisLiterature Analysis Lebel Lebel et alet al., (2008) ., (2008)

– Investigated the 10-year follow-up of 101 patients Investigated the 10-year follow-up of 101 patients who received autograft ACL reconstruction who received autograft ACL reconstruction specifically using a bone-patellar tendon-bone specifically using a bone-patellar tendon-bone (BPTB) autograft (BPTB) autograft

– International Knee Documentation Committee International Knee Documentation Committee (IKDC) score was statistically correlated to laxity, (IKDC) score was statistically correlated to laxity, time of injury and osteoarthritis development time of injury and osteoarthritis development

– Overall, the researchers found that 70 out of the Overall, the researchers found that 70 out of the 101 patients, average age 28, were still actively 101 patients, average age 28, were still actively participating in sports and ACL reconstruction using participating in sports and ACL reconstruction using BPTB autograft resulted in high patient satisfaction BPTB autograft resulted in high patient satisfaction levels and good clinical results 10 years post-op levels and good clinical results 10 years post-op

– Researchers also found that ACL reconstruction Researchers also found that ACL reconstruction with BPTB autograft protected patients from with BPTB autograft protected patients from secondary meniscus tears secondary meniscus tears

Literature AnalysisLiterature Analysis

Orenzi Orenzi et alet al. (2007) . (2007) – Performed retrospective clinical study Performed retrospective clinical study

assessing morbidity via proprioreceptive assessing morbidity via proprioreceptive differences and differences in laxity between differences and differences in laxity between autograft and allograft ACL reconstruction autograft and allograft ACL reconstruction

– Found that there is no significant difference in Found that there is no significant difference in comparing autograft to allograft ACL comparing autograft to allograft ACL reconstruction according to proprioreceptive reconstruction according to proprioreceptive measurements, and furthermore, measurements, and furthermore, proprioreception is not correlated to proprioreception is not correlated to postoperative anterior knee laxity postoperative anterior knee laxity

Literature AnalysisLiterature Analysis

Prodromos, Joyce and Shi (2007) Prodromos, Joyce and Shi (2007) – Conducted a meta-analysis assessing Conducted a meta-analysis assessing

the stability of autografts as compared the stability of autografts as compared to allografts for ACL reconstruction to allografts for ACL reconstruction using the IKDC stability criteria using the IKDC stability criteria a side-to-side difference of less than or a side-to-side difference of less than or

equal to 2mm is normal, and a difference of equal to 2mm is normal, and a difference of greater than 5mm is classified as abnormal greater than 5mm is classified as abnormal

Prodromos, Joyce and Shi Prodromos, Joyce and Shi (2007)(2007)

Graft <2 mm (%) P >5mm (%) P

Auto: all (56) 72 5  

Allo: all (19) 59 <0.01

14 <0.01

Allo: no rad (17) 63 <0.01

12 <0.01

Auto BPTB (32) 66 6  

Allo BPTB all (10) 57 0.02 16 0.01

Allo BPTB no rad (8) 62 <0.1

12

<0.01

Auto 4HS (24) 77 4  

Allo Sft Tx (9) 64 <0.01

12

<0.01

Graft stability rates by subgroup

Literature AnalysisLiterature Analysis Prodromos, Joyce and Shi (2007)Prodromos, Joyce and Shi (2007)

– The significance level was set at P < 0.05 The significance level was set at P < 0.05 and a P-value above this threshold would and a P-value above this threshold would indicate a lack of statistical significance.indicate a lack of statistical significance.

– The overall normal stability rate for all The overall normal stability rate for all autografts was 72% as compared to 59% for autografts was 72% as compared to 59% for all allograftsall allografts

– The authors also go on to mention a study The authors also go on to mention a study which was performed which found significant which was performed which found significant deterioration of allograft tissue and stability deterioration of allograft tissue and stability rates 10 years after implantationrates 10 years after implantation

Prodromos, Joyce and Shi Prodromos, Joyce and Shi (2007)(2007)

Overall Normal Stability Allograft vs Autograft in Anterior Cruciate Ligament Reconstruction

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10

20

30

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50

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80

90

Overall Normal Stability BPTB Normal Stability Hamstring Normal Stability

Stability

Per

cent Allograft

Autograft

Prodromos, Joyce and Shi Prodromos, Joyce and Shi (2007)(2007)

Overall Abnormal Stability Allograft vs Autograft in Anterior Cruciate Ligament Reconstruction

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Overall Abnormal Stability BPTB Abnormal Stability Hamstring Abnormal Stability

Stability

Perc

ent Allograft

Autograft

Literature AnalysisLiterature Analysis

Cause  Source

Immunologic response Schulte, Jackson

Freezing Cryolife

Lack of cryopreservation Cryolife

Increased donor age Kurzweil

Increased graft shelf time Sterling

Subclinical infection Carpenter

Radiation sterilization Noyes, Gorschewsky

Possible causes of increased allograft clinical laxity and sources of additional information

Literature AnalysisLiterature Analysis Gulotta and Rodeo (2007) Gulotta and Rodeo (2007)

– Performed a meta-analysis on the biology of Performed a meta-analysis on the biology of autograft and allograft healing in ACL autograft and allograft healing in ACL reconstruction reconstruction

– Found that BPTB autografts have shown to Found that BPTB autografts have shown to offer the strongest healing potential due to offer the strongest healing potential due to their reliance on bone-to-bone healing, their reliance on bone-to-bone healing, however are often associated with greater however are often associated with greater donor-site morbidity donor-site morbidity Hamstring autografts have less donor-site morbidity Hamstring autografts have less donor-site morbidity

but rely solely on tendon-to-bone healing which but rely solely on tendon-to-bone healing which occurs very slowly which may cause graft pull-out occurs very slowly which may cause graft pull-out or slippage resulting in instability or graft failureor slippage resulting in instability or graft failure

Literature AnalysisLiterature Analysis Gulotta and Rodeo (2007) Gulotta and Rodeo (2007)

– Also evaluated allograft healing in ACL Also evaluated allograft healing in ACL reconstruction, and how their incorporation reconstruction, and how their incorporation and remodeling are slower making and remodeling are slower making allografts more vulnerable to failure allografts more vulnerable to failure

– Aside from slower healing, the authors Aside from slower healing, the authors found that at 6 months post-operatively, found that at 6 months post-operatively, autografts demonstrate better restraints to autografts demonstrate better restraints to anterior-posterior displacement, double the anterior-posterior displacement, double the load-to-failure strength, a significant load-to-failure strength, a significant increase in the cross-sectional area of the increase in the cross-sectional area of the graft and more small-diameter collagen graft and more small-diameter collagen fibrils than allografts likely due to the fibrils than allografts likely due to the prolonged presence of an inflammatory prolonged presence of an inflammatory response with allograftresponse with allograft

Literature AnalysisLiterature Analysis Poolman, Poolman, et al.et al. (2007) (2007)

– Performed a meta-analysis comparing patient Performed a meta-analysis comparing patient morbidity post-ACL reconstruction with either a BPTB morbidity post-ACL reconstruction with either a BPTB or a hamstring autograft or a hamstring autograft

– Found that patients in general experienced Found that patients in general experienced significantly less anterior-knee pain with hamstring significantly less anterior-knee pain with hamstring autografts (relative risk 0.49 (95% CI: 0.32-0.76; autografts (relative risk 0.49 (95% CI: 0.32-0.76; p=0.001, I2 = 0%))p=0.001, I2 = 0%)) while maintaining stability as while maintaining stability as tested with a Lachman test tested with a Lachman test

– In general, morbidity associated with autographs has In general, morbidity associated with autographs has steadily decreased since 1991steadily decreased since 1991

Biau, Biau, et al.et al. (2006) (2006)– Performed meta-analysis comparing patient Performed meta-analysis comparing patient

morbidity post-ACL reconstruction with either a BPTB morbidity post-ACL reconstruction with either a BPTB or a hamstring autograft or a hamstring autograft

– Found that hamstring autografts were associated Found that hamstring autografts were associated with lower morbidity as compared to BPTB with lower morbidity as compared to BPTB concerning anterior knee pain and kneelingconcerning anterior knee pain and kneeling

Literature AnalysisLiterature Analysis Busam and Rue (2007) Busam and Rue (2007)

– Reasons to consider allograft for ACL Reasons to consider allograft for ACL reconstruction over autograft:reconstruction over autograft: Age greater than 40 yearsAge greater than 40 years radiologic evidence of mild degenerative joint radiologic evidence of mild degenerative joint

diseasedisease moderate patellofemoral crepitation or pain moderate patellofemoral crepitation or pain

symptomssymptoms petite staturepetite stature questionable quality of donor graft tissuequestionable quality of donor graft tissue patient request for allograft tissuepatient request for allograft tissue multi-ligamentous injuriesmulti-ligamentous injuries

Literature AnalysisLiterature Analysis Busam and Rue (2007) Busam and Rue (2007)

– In the case of graft-construct mismatch, the authors In the case of graft-construct mismatch, the authors mention several options for salvage including recessing mention several options for salvage including recessing the femoral tunnel, using femoral suspension fixation the femoral tunnel, using femoral suspension fixation to recess the graft further while avoiding the risk of to recess the graft further while avoiding the risk of graft laceration with an interference screw and rotating graft laceration with an interference screw and rotating the graft by 540 degrees to shorten the graft 5-6mm the graft by 540 degrees to shorten the graft 5-6mm

– For a more significant mismatch, a free tibial bone For a more significant mismatch, a free tibial bone block technique may be performed in which the tendon block technique may be performed in which the tendon is resected from the bone plug and a Krackow suture is is resected from the bone plug and a Krackow suture is placed in the tendon. After the femoral side of the placed in the tendon. After the femoral side of the graft is secured, the bone plug is placed anterior to soft graft is secured, the bone plug is placed anterior to soft tissue within the tibial tunnel while tension is tissue within the tibial tunnel while tension is maintained on the graft and the bone plug to prevent maintained on the graft and the bone plug to prevent dislodgement. dislodgement.

Literature AnalysisLiterature Analysis Hantes Hantes et alet al. (2008) . (2008)

– Performed a clinical study measuring contamination Performed a clinical study measuring contamination during autograft preparation in ACL reconstruction in during autograft preparation in ACL reconstruction in patients age 18-38 patients age 18-38

– Two groups were randomly assigned to either a BPTB Two groups were randomly assigned to either a BPTB autograft group and a hamstring autograft group, all autograft group and a hamstring autograft group, all receiving standard antibiotic treatment receiving standard antibiotic treatment pre/postoperativelypre/postoperatively

– It was found that 12% of the patients in the BPTB group It was found that 12% of the patients in the BPTB group and 13% of the patients in the hamstring group had and 13% of the patients in the hamstring group had positive bacterial cultures (Staphylococcus majority) positive bacterial cultures (Staphylococcus majority) one hour post-op but remained asymptomaticone hour post-op but remained asymptomatic

– Conclusion: minimal contamination may occur in Conclusion: minimal contamination may occur in autograft ACL reconstruction without going on to cause autograft ACL reconstruction without going on to cause infection infection

So, where does that leave So, where does that leave us?us?

Successful 10-15 year follow-up: Successful 10-15 year follow-up: AutograftAutograft

Proprioreceptive differences: NoneProprioreceptive differences: None Greater stability: AutograftGreater stability: Autograft Greater likelihood of infection: AllograftGreater likelihood of infection: Allograft Decreased donor-site morbidity: Decreased donor-site morbidity:

Allograft/Hamstring AutograftAllograft/Hamstring Autograft Greater overall success rate: AutograftGreater overall success rate: Autograft

When it all boils down..When it all boils down.. When young, athletic patients are facing When young, athletic patients are facing

ACL reconstruction and having to choose a ACL reconstruction and having to choose a graft choice, one of their main priorities is graft choice, one of their main priorities is getting back to successfully playing their getting back to successfully playing their sport as soon as possiblesport as soon as possible

Patients receiving autografts are able to Patients receiving autografts are able to safely initiate aggressive physical therapy safely initiate aggressive physical therapy sooner than those receiving allograftsooner than those receiving allograft

Early initiation of rehabilitation Early initiation of rehabilitation Quicker Quicker return to sport return to sport happy athletes! happy athletes!

Is allograft all that bad? No.Is allograft all that bad? No.

Autograft may not be the best choice Autograft may not be the best choice for all patients in need of ACL for all patients in need of ACL reconstructionreconstruction

Allograft may be a reasonable option Allograft may be a reasonable option for certain patient populations, for certain patient populations, including those with multi-including those with multi-ligamentous injury, questionable ligamentous injury, questionable quality of donor graft tissue, etc. quality of donor graft tissue, etc.

Better graft?Better graft?

Though there are several studies favoring one Though there are several studies favoring one graft or another, one should be cautious when graft or another, one should be cautious when saying that one graft is “better” than anothersaying that one graft is “better” than another

Neither autograft nor allograft match the Neither autograft nor allograft match the quality of the native ACLquality of the native ACL

Many factors must be taken into Many factors must be taken into consideration:consideration:– Surgeon choiceSurgeon choice– Patient choicePatient choice– Patient receiving graftPatient receiving graft

ApplicationApplication

Practitioners must be able to Practitioners must be able to adequately counsel patients as to their adequately counsel patients as to their options for ACL reconstructionoptions for ACL reconstruction

Based upon this research, young, Based upon this research, young, athletic patients with a complete ACL athletic patients with a complete ACL tear would highly benefit from a BPTB tear would highly benefit from a BPTB or hamstring autograft for or hamstring autograft for reconstructionreconstruction

What needs to be done?What needs to be done?

MORE RESEARCH!MORE RESEARCH! In order to reliably compare the two In order to reliably compare the two

options for ACL reconstruction, more options for ACL reconstruction, more up-to-date prospective, controlled up-to-date prospective, controlled clinical studies need be completed clinical studies need be completed directly comparing autografts to directly comparing autografts to allografts regarding post-operative allografts regarding post-operative infection rates, rehabilitation, knee infection rates, rehabilitation, knee stability and graft failure rates.stability and graft failure rates.

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Meunier, A.; Odensten, M. Good, L. Meunier, A.; Odensten, M. Good, L. (2007) (2007) Long-term results after primary repair or non-surgical treatment of anterior cruciate ligament rupture: a randomized study with a 15-year follow-up. AbstractPreview Find Similar Articles. AbstractPreview Find Similar Articles. Scandinavian Journal of Medicine & Science in Scandinavian Journal of Medicine & Science in Sports. 17(3): 230-7. Retrieved January 19, 2009. Sports. 17(3): 230-7. Retrieved January 19, 2009.

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Ozenci, A.; Inanmaz, Erkan; Ozcanli, Haluk; Soyuncu, Yetkin; Samanci, Nehir; Dagseven, Tufan; Ozenci, A.; Inanmaz, Erkan; Ozcanli, Haluk; Soyuncu, Yetkin; Samanci, Nehir; Dagseven, Tufan; Balci, Nilüfer; Gur, Semih. (2007) Balci, Nilüfer; Gur, Semih. (2007) Proprioceptive comparison of allograft and autograft Proprioceptive comparison of allograft and autograft anterior cruciate ligament reconstructions.anterior cruciate ligament reconstructions. Knee Surgery, Sports Traumatology, Knee Surgery, Sports Traumatology, Arthroscopy, Vol. 15 Issue 12, p1432-1437. Retrieved January 19, 2009. Arthroscopy, Vol. 15 Issue 12, p1432-1437. Retrieved January 19, 2009.

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Hantes, Michael E, MD; Basdekis, Georgios K, MD; Varitimidis, Sokratis E., MD; Giotikas, Hantes, Michael E, MD; Basdekis, Georgios K, MD; Varitimidis, Sokratis E., MD; Giotikas, Dimitrios, MD; Petinaki, Efthimia, MD; Malizos, Konstantinos N. (2008) Dimitrios, MD; Petinaki, Efthimia, MD; Malizos, Konstantinos N. (2008) Autograft Autograft Contamination During Preparation for Anterior Cruciate Ligament Reconstruction.Contamination During Preparation for Anterior Cruciate Ligament Reconstruction. The The Journal of Bone and Joint Surgery. 90: 760-4. Retrieved January 27, 2009. Journal of Bone and Joint Surgery. 90: 760-4. Retrieved January 27, 2009.

Schoderberbek, Robert J. Jr, MD; Treme, Gehron P.; Miller, Mark D., MD. (2007) Schoderberbek, Robert J. Jr, MD; Treme, Gehron P.; Miller, Mark D., MD. (2007) Bone-Patella Bone-Patella Tendon-Bone Autograft in Anterior Cruciate Ligament ReconstructionTendon-Bone Autograft in Anterior Cruciate Ligament Reconstruction. Clinics in Sports . Clinics in Sports Medicine. 26(4): 525-47. Retrieved January 27, 2009. Medicine. 26(4): 525-47. Retrieved January 27, 2009.

Biau, D.J; Tournoux, C ; Katsahian, S. ; Schranz, P.J. ; Nizard, R.S..(2006) Bone-patellar tendon-bone autografts versus hamstring autografts for reconstruction of the anterior cruciate ligament: meta-analysis. BMJ. 332(7548):995-1001. Epub. Retrieved February 2, 2009.

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P1 in a nutshell:P1 in a nutshell: