An interventional study of Patellar Tendon and Hamstring Tendon in Anterior Cruciate Ligament Rupture, Deficiency of Anterior Cruciate Ligament and Chronic Instability of Knee, sponsored by University of Calgary. Completed at 1 site in Canada. Open to participants aged 14 Years to 50 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2024-12-11.
Sponsored by University of Calgary · Not applicable, Interventional, and Treatment
The purpose of this randomized clinical trial is to determine the difference in quality of life outcome at two years, in patients undergoing an Anterior Cruciate Ligament (ACL) reconstruction procedure with either a patellar tendon, quadruple hamstring tendon or a double-bundle hamstring tendon autograft.
Following an ACL injury, the knee is predisposed to chronic instability, further damage to the meniscal and chondral structures in the knee, osteoarthritis and an impaired quality of life. The successful treatment of an ACL deficient knee aims to preserve the intact meniscus and chondral structures, and to provide a functionally stable knee so that patients can return to pre-injury activities and restore their quality of life. The current standard of care for ACL deficient knees is with a surgical ACL reconstruction procedure. A Cochrane Review was done and demonstrated that the existing literature is controversial. To date, no existing trial has used validated patient-based outcome assessment, accounted for the critical differences between acute and chronic ACL deficiency or used modern techniques to ensure randomization concealment and a sufficient sample size to avoid type II error. The existing information does not define graft failure or re-ruptures, involve long-term follow-up to address osteoarthritis development, nor compare outcomes between single- and double-bundle reconstructive techniques. The current standard includes either a patellar tendon or quadruple semitendinosus/gracilis tendon autograft reconstruction. The newest option is a double-bundle semitendinosus/gracilis graft. This option attempts to restore the complex ACL anatomy by using two separate tendon components to reconstruct the ACL. This study will measure disease-specific quality of life at short- and long-term post-operative intervals (1, 2, 5 and 10 years). Additional secondary outcomes, including the incidence of traumatic re-ruptures and graft failures, will also be compared between treatment groups.
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A confirmed diagnosis of anterior cruciate ligament deficiency based on all of the following:
Exclusion Criteria:
ACL reconstruction using a patellar tendon autograft
Procedure: Patellar Tendon
ACL reconstruction using a quadruple-strand semitendinosus/gracilis (hamstring) tendon single-bundle autograft
Procedure: Hamstring Tendon
ACL reconstruction using a semitendinosus/gracilis (hamstring) tendon double-bundle autograft
Procedure: Double-Bundle
Patellar Tendon autograft
Also known as: Bone-patellar tendon-bone graft, BTPB graft
Quadruple Semitendinosus/Gracilis (Hamstring) Tendon Autograft
Also known as: Single-bundle hamstring graft, ST/G graft
Double-Bundle Semitendinosus/Gracilis (Hamstring) Tendon Autograft
Also known as: Double-bundle ST/G graft
Anterior Cruciate Ligament Quality of Life (ACL-QOL) Outcome
The 32-item patient-reported Anterior Cruciate Ligament Quality-of-Life (ACL-QOL) questionnaire assesses symptoms/physical complaints, work-related, sports/recreational, lifestyle and social/emotional concerns. A higher score on the 0 to 100mm visual analog scale represents better quality of life.
Time frame: Baseline, 3 and 6 months, 1, 2, and 5 years post-operatively
Number of Participants With Traumatic ACL Re-ruptures and Atraumatic Graft Failures
* COMPLETE TRAUMATIC RE-RUPTURE - defined as a consequence of an acute traumatic event resulting in a change in static stability since the most recent follow-up visit; determined clinically by a definite loss of end point on Lachman testing, increased anterior translation (\>3mm) and a greater than or equal grade 2 pivot shift. Confirmed by MRI or diagnostic arthroscopy. * PARTIAL TRAUMATIC TEARS - defined as a consequence of an acute traumatic event resulting in a suspected meniscal injury or graft tear on history, without the clinical characteristics of a "complete traumatic rerupture". Confirmed by MR or diagnostic arthroscopy. * TRAUMATIC RE-INJURY - combined total of "complete traumatic re-ruptures" and "partial traumatic tears". * ATRAUMATIC GRAFT FAILURES - defined in the absence of an acute traumatic event, with greater than or equal grade 2 pivot shift and/or greater than or equal to 6mm side-to-side difference on the KT arthrometer.
Time frame: Minimum 2-year Follow-up, 5-Year Follow-up, 10-Year Follow-up
Number of Participants With Each International Knee Documentation Committee (IKDC) Objective Overall Group Grade
IKDC Objective group grades: Normal (A), Nearly Normal (B), Abnormal (C), Severely Abnormal (D) The IKDC Objective Overall Group Grade is determined by the lowest grade assigned to defined objective knee examination measurements, including effusion, passive motion deficit and manual/instrumented ligament examinations (i.e. Lachman, anterior-posterior (AP) translation).
Time frame: Baseline, 1, 2, 5 years post-operatively
Mean International Knee Documentation Committee (IKDC) Subjective Score
Patient-reported health-related outcome measure with a score between 0 and 100. A higher score represents a better outcome.
Time frame: Baseline, 3 and 6 months, 1, 2 and 5 years post-operatively
Number of Participants With Each Pivot Shift Grade
The Pivot Shift test is a dynamic, passive test to assess the rotational instability of the Anterior Cruciate Ligament in the knee. Pivot shift grades include: equal/0 (negative); glide/1; clunk/2; gross/3. A positive grade indicates injury to the Anterior Cruciate Ligament.
Time frame: Baseline, 3 and 6 months, 1, 2 and 5 years post-operatively
Proportion of Patients With Moderate or Severe Kneeling Pain
Patients kneeled down on the same hard surface (i.e. clinic floor) and self-reported the pain on a scale of: none, mild, moderate or severe. The number of patients reporting moderate or severe kneeling pain were combined in the reported proportions.
Time frame: Baseline, 2 and 5 years post-operatively
Knee Laxity as Measured by the KT Arthrometer
Mean side-to-side differences, as measured using the KT-1000 Arthrometer instrument at 30lbs/134N forces to objectively measure knee laxity.
Time frame: Baseline, 1 and 2 years post-operatively
Mean Tegner Activity Level
Tegner Activity Scale (Values indicate level of activity from inactive (Level 0) to competitive level of activity (Level 10))
Time frame: Baseline, 6 months, 1 and 2 years post-operatively
Return to Pre-injury Tegner Activity Level
Proportion of patients returning to pre-injury levels, as measured by the Tegner Activity Scale (Values indicate level of activity from inactive (Level 0) to competitive level of activity (Level 10)).
Time frame: 1, 2 and 5 years post-operatively
Cincinnati Occupational Rating Scale
The Cincinnati Occupational Rating Scale assesses the level of work-related activities, including sitting, standing, walking, squatting, climbing, lifting and carrying weighted objects. The score ranges from 0 to 100, with a lower score representing more sedentary work-related activities.
Time frame: Baseline, 3 and 6 months, 1, 2 and 5 years post-operatively
Skin-to-Skin Operative Times
Skin-to-skin operative times (in minutes) for each ACL reconstruction procedure
Time frame: During surgery
Radiographic (X-ray) Changes
The analysis for the radiographic assessment data is currently ongoing, to provide a comparison of baseline, 2- and 5-year post-operative x-rays.
Time frame: Baseline, 2 and 5 years post-operatively
Complications of the Surgical Procedure (See Adverse Events Section for Results of This Outcome)
All complications/adverse events that occurred within the first two-years post-operatively. See Adverse Events section for results of this outcome.
Time frame: 2 years post-operatively
| Milestone | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Started | 110 | 110 | 110 |
| Completed | 106 | 108 | 108 |
| Not completed | 4 | 2 | 2 |
| Withdrew: Lost to follow-up | 1 | 2 | 2 |
| Withdrew: Withdrawal by subject | 3 | 0 | 0 |
| Milestone | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Started | 106 | 108 | 108 |
| Completed | 103 | 105 | 107 |
| Not completed | 3 | 3 | 1 |
| Withdrew: Lost to follow-up | 2 | 3 | 1 |
| Withdrew: Withdrawal by subject | 1 | 0 | 0 |
The 32-item patient-reported Anterior Cruciate Ligament Quality-of-Life (ACL-QOL) questionnaire assesses symptoms/physical complaints, work-related, sports/recreational, lifestyle and social/emotional concerns. A higher score on the 0 to 100mm visual analog scale represents better quality of life.
| Score (0 to 100) | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Baseline | 27.0 ± 13.1 | 29.8 ± 14.7 | 28.7 ± 13.7 |
| 3 Months | 47.7 ± 17.2 | 52.6 ± 19.2 | 50.5 ± 16.9 |
| 6 Months | 61.7 ± 19.1 | 65.2 ± 18.4 | 65.5 ± 17.9 |
| 1-Year | 74.5 ± 18.7 | 75.4 ± 18.5 | 73.6 ± 19.2 |
| 2-Years | 84.6 ± 16.6 | 82.5 ± 17.7 | 82.4 ± 17.5 |
| 5-Years | 82.5 ± 17.9 | 83.9 ± 18.2 | 81.1 ± 19.3 |
* COMPLETE TRAUMATIC RE-RUPTURE - defined as a consequence of an acute traumatic event resulting in a change in static stability since the most recent follow-up visit; determined clinically by a definite loss of end point on Lachman testing, increased anterior translation (\>3mm) and a greater than or equal grade 2 pivot shift. Confirmed by MRI or diagnostic arthroscopy. * PARTIAL TRAUMATIC TEARS - defined as a consequence of an acute traumatic event resulting in a suspected meniscal injury or graft tear on history, without the clinical characteristics of a "complete traumatic rerupture". Confirmed by MR or diagnostic arthroscopy. * TRAUMATIC RE-INJURY - combined total of "complete traumatic re-ruptures" and "partial traumatic tears". * ATRAUMATIC GRAFT FAILURES - defined in the absence of an acute traumatic event, with greater than or equal grade 2 pivot shift and/or greater than or equal to 6mm side-to-side difference on the KT arthrometer.
| Participants | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Minimum 2-Year Follow-up — No re-injury or failure | 91 | 81 | 79 |
| Minimum 2-Year Follow-up — Complete Traumatic Re-rupture | 3 | 7 | 7 |
| Minimum 2-Year Follow-up — Partial Traumatic Tear | 0 | 5 | 4 |
| Minimum 2-Year Follow-up — Atraumatic Graft Failure | 16 | 17 | 20 |
| 5-Year Follow-up — No re-injury or failure | 92 | 80 | 76 |
| 5-Year Follow-up — Complete Traumatic Re-rupture | 4 | 11 | 11 |
| 5-Year Follow-up — Partial Traumatic Tear | 0 | 5 | 6 |
| 5-Year Follow-up — Atraumatic Graft Failure | 7 | 9 | 14 |
IKDC Objective group grades: Normal (A), Nearly Normal (B), Abnormal (C), Severely Abnormal (D) The IKDC Objective Overall Group Grade is determined by the lowest grade assigned to defined objective knee examination measurements, including effusion, passive motion deficit and manual/instrumented ligament examinations (i.e. Lachman, anterior-posterior (AP) translation).
| Participants | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Baseline — Normal (A) | 0 | 0 | 0 |
| Baseline — Nearly Normal (B) | 1 | 4 | 5 |
| Baseline — Abnormal (C) | 103 | 101 | 100 |
| Baseline — Severely Abnormal (D) | 5 | 4 | 5 |
| 1-Year — Normal (A) | 9 | 9 | 9 |
| 1-Year — Nearly Normal (B) | 79 | 77 | 71 |
| 1-Year — Abnormal (C) | 13 | 18 | 19 |
| 1-Year — Severely Abnormal (D) | 0 | 0 | 2 |
| 2-Years — Normal (A) | 12 | 12 | 19 |
| 2-Years — Nearly Normal (B) | 65 | 62 | 56 |
| 2-Years — Abnormal (C) | 23 | 28 | 30 |
| 2-Years — Severely Abnormal (D) | 1 | 2 | 2 |
| 5-Years — Normal (A) | 24 | 18 | 19 |
| 5-Years — Nearly Normal (B) | 61 | 63 | 58 |
| 5-Years — Abnormal (C) | 13 | 18 | 24 |
| 5-Years — Severely Abnormal (D) | 0 | 0 | 2 |
Patient-reported health-related outcome measure with a score between 0 and 100. A higher score represents a better outcome.
| score on a scale (out of 100) | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Baseline | 50.1 ± 13.9 | 51.0 ± 16.2 | 51.5 ± 14.6 |
| 3 Months | 60.2 ± 12.2 | 65.7 ± 14.2 | 63.1 ± 12.1 |
| 6 Months | 71.1 ± 11.1 | 76.1 ± 13.1 | 75.8 ± 11.1 |
| 1-Year | 79.7 ± 11.7 | 81.7 ± 12.6 | 80.0 ± 11.9 |
| 2-Years | 84.6 ± 13.8 | 85.3 ± 11.6 | 84.2 ± 11.8 |
| 5-Years | 83.9 ± 12.9 | 85.2 ± 13.0 | 84.3 ± 13.4 |
The Pivot Shift test is a dynamic, passive test to assess the rotational instability of the Anterior Cruciate Ligament in the knee. Pivot shift grades include: equal/0 (negative); glide/1; clunk/2; gross/3. A positive grade indicates injury to the Anterior Cruciate Ligament.
| Participants | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Baseline — Equal | 0 | 1 | 0 |
| Baseline — Glide (+) | 6 | 6 | 9 |
| Baseline — Clunk (++) | 103 | 102 | 99 |
| Baseline — Gross (+++) | 1 | 1 | 2 |
| 3 Months — Equal | 73 | 60 | 80 |
| 3 Months — Glide (+) | 30 | 45 | 25 |
| 3 Months — Clunk (++) | 1 | 1 | 2 |
| 3 Months — Gross (+++) | 0 | 0 | 0 |
| 6 Months — Equal | 62 | 53 | 66 |
| 6 Months — Glide (+) | 38 | 45 | 39 |
| 6 Months — Clunk (++) | 3 | 5 | 2 |
| 6 Months — Gross (+++) | 0 | 0 | 0 |
| 1-Year — Equal | 47 | 46 | 53 |
| 1-Year — Glide (+) | 51 | 48 | 41 |
| 1-Year — Clunk (++) | 3 | 12 | 7 |
| 1-Year — Gross (+++) | 0 | 0 | 1 |
| 2-Years — Equal | 36 | 28 | 38 |
| 2-Years — Glide (+) | 52 | 57 | 49 |
| 2-Years — Clunk (++) | 14 | 18 | 19 |
| 2-Years — Gross (+++) | 0 | 1 | 1 |
| 5-Years — Equal | 37 | 29 | 30 |
| 5-Years — Glide (+) | 50 | 54 | 50 |
| 5-Years — Clunk (++) | 12 | 16 | 22 |
| 5-Years — Gross (+++) | 0 | 0 | 1 |
Patients kneeled down on the same hard surface (i.e. clinic floor) and self-reported the pain on a scale of: none, mild, moderate or severe. The number of patients reporting moderate or severe kneeling pain were combined in the reported proportions.
| Participants | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Baseline | 29 | 29 | 18 |
| 2 Years | 17 | 9 | 4 |
| 5 Years | 10 | 4 | 2 |
Mean side-to-side differences, as measured using the KT-1000 Arthrometer instrument at 30lbs/134N forces to objectively measure knee laxity.
| Millimetres (side-to-side difference) | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Baseline | 4.9 ± 2.3 | 5.0 ± 2.1 | 5.1 ± 2.3 |
| 1-Year | 1.9 ± 2.3 | 2.8 ± 1.8 | 2.8 ± 2.2 |
| 2-Years | 1.9 ± 2.5 | 3.0 ± 2.1 | 2.7 ± 2.4 |
Tegner Activity Scale (Values indicate level of activity from inactive (Level 0) to competitive level of activity (Level 10))
| Activity Level | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Baseline | 7.7 ± 1.7 | 7.9 ± 1.7 | 7.9 ± 1.6 |
| 6 Months | 4.7 ± 1.6 | 4.8 ± 1.6 | 5.0 ± 1.7 |
| 1 Year | 6.0 ± 1.8 | 6.1 ± 1.9 | 5.9 ± 2.0 |
| 2 Years | 6.5 ± 1.8 | 6.4 ± 2.0 | 6.4 ± 1.9 |
Proportion of patients returning to pre-injury levels, as measured by the Tegner Activity Scale (Values indicate level of activity from inactive (Level 0) to competitive level of activity (Level 10)).
| Participants | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| 1 Year | 27 | 33 | 28 |
| 2 Years | 44 | 43 | 36 |
| 5 Years | 35 | 41 | 41 |
The Cincinnati Occupational Rating Scale assesses the level of work-related activities, including sitting, standing, walking, squatting, climbing, lifting and carrying weighted objects. The score ranges from 0 to 100, with a lower score representing more sedentary work-related activities.
| score on a scale (out of 100) | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Baseline | 36.6 ± 19.9 | 35.4 ± 21.3 | 36.3 ± 17.7 |
| 3 Months | 34.7 ± 17.2 | 36.1 ± 22.1 | 36.4 ± 19.3 |
| 6 Months | 35.7 ± 18.3 | 37.4 ± 21.6 | 37.0 ± 20.2 |
| 1 Year | 36.7 ± 17.2 | 38.0 ± 22.0 | 38.0 ± 21.5 |
| 2 Years | 36.8 ± 19.4 | 34.4 ± 22.1 | 38.0 ± 22.5 |
| 5 Years | 35.9 ± 18.4 | 36.6 ± 23.8 | 37.8 ± 24.2 |
Skin-to-skin operative times (in minutes) for each ACL reconstruction procedure
| Minutes | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Skin-to-Skin Operative Times | 75.3 ± 14.7 | 67.8 ± 14.6 | 88.0 ± 14.9 |
The analysis for the radiographic assessment data is currently ongoing, to provide a comparison of baseline, 2- and 5-year post-operative x-rays.
Results for this outcome have not been posted.
All complications/adverse events that occurred within the first two-years post-operatively. See Adverse Events section for results of this outcome.
| Participants | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Deep wound infection | 1 | 0 | 0 |
| Superficial wound infection | 0 | 2 | 2 |
| Chondral lesion | 1 | 0 | 1 |
| Failed meniscal repair | 2 | 6 | 4 |
| Stiffness | 4 | 2 | 3 |
| Hamstring injury | 1 | 6 | 12 |
| Tibial periostitis | 1 | 2 | 4 |
| Stitch abscess | 2 | 1 | 0 |
| Cellulitis | 0 | 0 | 3 |
| Meniscal cyst | 1 | 0 | 0 |
| Patellar tendinopathy | 1 | 0 | 0 |
| Persistent effusion / inflammation | 1 | 2 | 5 |
| Sensory nerve problems | 4 | 1 | 3 |
| Wound dehiscence | 1 | 0 | 1 |
| Hardware issues | 0 | 0 | 0 |
| Massive pulmonary embolism | 0 | 0 | 1 |
| Deep vein thrombosis | 0 | 0 | 1 |
| Septic arthritis | 0 | 1 | 0 |
Collected over Two years post-operatively.. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Patellar Tendon (PT) | 0/110 (0%) | 0/110 (0%) | 20/110 (18.2%) |
| Hamstring (HT) | 0/110 (0%) | 1/110 (0.9%) | 22/110 (20%) |
| Double-Bundle (DB) | 0/110 (0%) | 2/110 (1.8%) | 38/110 (34.5%) |
| Event | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Septic ArthritisInfections and infestations | 0/110 | 1/110 | 0/110 |
| Massive Pulmonary EmbolismBlood and lymphatic system disorders | 0/110 | 0/110 | 1/110 |
| Deep Vein ThrombosisBlood and lymphatic system disorders | 0/110 | 0/110 | 1/110 |
| Event | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) |
|---|---|---|---|
| Hamstring InjuryMusculoskeletal and connective tissue disorders | 1/110 | 6/110 | 12/110 |
| Failed Meniscal RepairMusculoskeletal and connective tissue disorders | 2/110 | 6/110 | 4/110 |
| Persistent Effusion/InflammationMusculoskeletal and connective tissue disorders | 1/110 | 2/110 | 5/110 |
| StiffnessMusculoskeletal and connective tissue disorders | 4/110 | 2/110 | 3/110 |
| Tibial PeriostitisMusculoskeletal and connective tissue disorders | 1/110 | 2/110 | 4/110 |
| Sensory Nerve ProblemsNervous system disorders | 4/110 | 1/110 | 3/110 |
| CellulitisMusculoskeletal and connective tissue disorders | 0/110 | 0/110 | 3/110 |
| Superficial Wound InfectionInfections and infestations | 0/110 | 2/110 | 2/110 |
| Stitch AbscessMusculoskeletal and connective tissue disorders | 2/110 | 1/110 | 0/110 |
| Deep Wound InfectionInfections and infestations | 1/110 | 0/110 | 0/110 |
N=110 patients were randomized to each study group. One cross-over from the DB group received an HT graft, but was analyzed as part of the DB study group.
| Age, Continuous(years) | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) | Total |
|---|---|---|---|---|
| Mean | 28.7 ± 9.7 | 28.5 ± 9.9 | 28.3 ± 9.8 | 28.5 ± 9.8 |
| Sex: Female, Male(Participants) | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) | Total |
|---|---|---|---|---|
| Female | 47 | 51 | 49 | 147 |
| Male | 63 | 59 | 61 | 183 |
| Chronicity: Acute, Chronic(Participants) | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) | Total |
|---|---|---|---|---|
| Acute | 16 | 16 | 17 | 49 |
| Chronic | 94 | 94 | 93 | 281 |
| Injured side: Left, Right(Participants) | Patellar Tendon (PT) | Hamstring (HT) | Double-Bundle (DB) | Total |
|---|---|---|---|---|
| Left | 54 | 63 | 54 | 171 |
| Right | 56 | 47 | 56 | 159 |
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