Soft Tissue Allografts Research Articles

Intralimb Coordination Pattern of the Lower Limbs in Male Athletes With Allograft and Autograft Anterior Cruciate Ligament Reconstruction During Landing

Background and Objectives: Two common choices exist for anterior cruciate ligament (ACL) reconstruction, autograft and allograft. Hamstring tendon autografts and soft-tissue allografts are commonly used for ACL reconstruction. The outcomes between these two grafts are controversial. This research aims to quantify and compare lower limb joint coordination between two ACL reconstruction graft options and healthy individuals. Methods: Sixty-one athletes were enrolled after ACL reconstruction surgery (allograft, n=22; autograft, n=18). Furthermore, twenty-one healthy athletes were considered in the control group. The inclusion criteria included unilateral anterior cruciate ligament reconstruction surgery with allograft and autograft methods, male athletes with a minimum of 9 months and a maximum of two years since their surgery, successfully passing a series of quadriceps and hamstring strength tests and distance jumping before entering sports-specific activities under the supervision of a sports physiotherapist, and returning to pre-injury sports activities. Results: Autograft was not statistically different from matched healthy limbs in terms of joint coordination variability and magnitude (P>0.05). However, the magnitude of joint coordination was superior to the allograft group compared to the autograft reconstructed ACL (P<0.05). Conclusion: Although our result reported no significant difference between groups in joint coordination variability, having an insight into coordinative function after ACL reconstruction will help develop postoperative rehabilitation programs as well as minimize the re-injury risk among patients. We also suggest that scholars should conduct more robust trials with valid research designs to control the results of ACL reconstruction comparison with autograft and allograft.

Influence of Staphylococcus epidermidis on Collagen Crimp Patterns of Soft Tissue Allograft

Background: Postoperative infections, commonly from Staphylococcus epidermidis, may result in anterior cruciate ligament graft failure and necessitate revision surgery. In biomechanical studies, S. epidermidis has been shown to establish biofilms on tendons and reduce graft strength. Purpose/Hypothesis: The goal of this study was to determine the effect of bacterial bioburden on the collagen structure of tendon. It was hypothesized that an increase in S. epidermidis biofilm would compromise tendon crimp, a pattern necessary for mechanical integrity, of soft tissue allografts. Study design: Controlled laboratory study. Methods: Cultures of S. epidermidis were used to inoculate tibialis anterior cadaveric tendons. Conditions assessed included 5 × 105 colony-forming units or concentrated spent media from culture (no living bacteria). Incubation times of 30 minutes, 3 hours, 6 hours, and 24 hours were utilized. Second-harmonic generation imaging allowed for visualization of collagen autofluorescence. Crimp lengths were determined using ImageJ and compared based on incubation time. Results: Incubation time positively correlated with increasing S. epidermidis bioburden. Both fine and coarse crimp patterns lengthened with increasing incubation time. Significant coarse crimp changes were observed after only 30-minute incubations (P < .029), whereas significant fine crimp lengthening occurred after 6 hours (P < .0001). No changes in crimp length were identified after incubation in media lacking living bacteria. Conclusion: The results of this study demonstrate that exposure to S. epidermidis negatively affects collagen crimp structure. Structural alterations at the collagen fiber level occur within 30 minutes of exposure to media containing S. epidermidis. Clinical Relevance: Our study highlights the need for antimicrobial precautions to prevent graft colonization and maximize graft mechanical strength.

A randomised controlled study for the comparison of functional outcome of femoral tunnel fixation devices, aperture fixation by screw vs suspensory fixation by endo-button in arthroscopic anterior cruciate ligament reconstruction

: The goal of this study was to compare suspensory and aperture fixation methods for restoring soft tissue allografts in the anterior cruciate ligament (ACL).: 30 patients were chosen and randomly allocated to one of two experimental groups, suspensory fixation or aperture fixation, following the completion of a prospective analysis, permission from the institutional review board, and patient agreement. All of the patients underwent ACL reconstruction surgery using soft tissue allografts made of hamstring tendon. The procedures were either (1) femoral and tibial fixation with a femoral cannulated interference screw and a tibial cannulated interference screw (aperture) or (2) femoral cortical buttons (suspensory) and a tibial cannulated interference screw. The subjective anterior drawer test analysis and changes in the International Knee Documentation Committee knee examination rating were employed as end measures.: All of the patients who had received treatment (100%) had successfully completed a clinical assessment at the 1-month, 4-month, 8-month, and 12-month follow-ups. Out of the 30 patients who were included, 15 (50%) underwent suspensory fixation treatment and the other 15 (50%) underwent aperture fixation treatment. The primary outcome measure—AP stability at 25 degrees of knee flexion—did not differ across groups at a 12-month follow-up. Also, at the 1-month and 4-month evaluations, secondary data revealed a statistically significant difference between the groups.: Our data showed no meaningful differences in knee AP stability or other outcomes between ACL allograft reconstruction using aperture fixation and ACL allograft reconstruction utilising suspensory fixation at the 12-month mark, while aperture fixation performed better at the first and fourth months. One of our main outcome measures was the grading of knee anteroposterior (AP) stability (clinical judgments).: Level II, lesser-quality randomised controlled trial with a follow-up of 1 year.

Revision Soft-Tissue Allograft Anterior Cruciate Ligament Reconstruction Is Associated With Lower Patient-Reported Outcomes Compared With Primary Anterior Cruciate Ligament Reconstruction in Patients Aged 40 and Older

To evaluate patient-reported outcomes (PROs) and graft failure rates in revision allograft anterior cruciate ligament reconstruction (ACLR) in patients aged 40 and older and compare them with primary ACLRs. Patients aged 40 and older who underwent arthroscopic soft-tissue allograft ACLR between 2005 and 2016 with a minimum 2-year follow-up were retrospectively reviewed. Patients were grouped based on revision versus primary ACLR. The rate of achieving an International Knee Documentation Committee (IKDC) patient acceptable symptom state (PASS) score was recorded. Patient satisfaction, PROs, and graft failure were compared between groups using the χ2 test, Fisher exact test, and Mann-Whitney U test. We identified 32 patients who underwent revision ACLR and 201 patientswho underwent primary ACLR aged 40 and older who met inclusion criteria with a mean follow-up of 6.2 and 6.9 years, respectively (P= .042). There was a lower rate of concomitant meniscal repair in the primary ACLR group (6%vs 21.9%, P= .007) There were no other differences in chondral injuries, mechanism of injury, or meniscal injuries between groups. The median IKDC score was greater in the primary ACLR group as compared with the revision ACLR group (83.9 vs 70.6, P < .001). Patients who underwent revision ACLR were less likely to achieve the IKDC PASS threshold (82.5% vs 56.3%, P= .001) and were less likely to report satisfaction as compared with patients who underwent primary ACLR (90.5% vs 78.1%, P=.038). No difference in graft failure rates was identified between groups (8% vs 15.6%, P= .180). Revision allograft ACLR in patients aged 40 and older was associated with lower PROs compared with primary ACLR. Patients who underwent revision ACLR failed to meet the IKDC PASS threshold more often and were dissatisfied with procedure results more than twice as often as patients that underwent primary ACLR. III, retrospective cohort study.

Influence of Staphylococcus epidermidis biofilm on the mechanical strength of soft tissue allograft.

We sought to determine the impact of bacterial inoculation and length of exposure on the mechanical integrity of soft tissue tendon grafts. Cultures of Staphylococcusepidermidis were inoculated on human tibialis posteriorcadaveric tendon to grow biofilms. A low inoculum in 10% growth medium was incubated for 30 min to replicate conditions of clinical infection. Growth conditions assessed included inoculum concentrations of 100, 1000, 10,000 colony-forming units(CFUs). Tests using the MTS Bionix system were performed to assess the influence of bacterial biofilms on tendon strength. Load-to-failure testing was performed on the tendons, and the ultimate tensile strength was obtained from the maximal force and the cross-sectional area. Displacements of tendon origin to maximal displacement were normalized to tendon length to obtain strain values. Tendon force-displacement and stress-strain relationships were calculated, and Young's modulus was determined. Elastic modulus and ultimate tensile strength decreased with increasing bioburden. Young's modulus was greater in uninoculated controls compared to tendons inoculated at 10,000 CFU (p = 0.0011) but unaffected by bacterial concentrations of 100 and 1000 CFU (p = 0.054, p = 0.078). Increasing bioburden was associated with decreased peak load to failure (p = 0.043) but was most significant compared to the control under the 10,000and 1000 CFU growth conditions (p = 0.0005, p = 0.049). The presence of S. epidermidis increased elasticity and decreased ultimate tensile stress of human cadaveric tendons, with increasing effect noted with increasing bioburden.

Biomechanical Evaluation of Suture Tape Internal Brace Reinforcement of Soft Tissue Allografts for ACL Reconstruction Using a Porcine Model.

Background:Internal bracing of anterior cruciate ligament (ACL) surgery is a newer concept gaining popularity.Purpose/Hypothesis:To assess the biomechanical performance of soft tissue ACL reconstruction allografts reinforced with suture tape. It was hypothesized that load to failure would increase and cyclic displacement would decrease at time zero in the constructs reinforced with internal brace suture tape compared with those without suture tape augmentation.Study Design:Controlled laboratory study.Methods:We performed ACL reconstruction on porcine knees using bovine extensor tendon soft tissue allografts: 10 knees without (control) and 10 knees with (reinforced) suture tape reinforcement. An all-inside reconstruction technique was utilized with retrograde tunnel creation. An adjustable-loop device was used for femoral and tibial fixation of all grafts. The suture tape was placed through the tension loop in the femoral fixation construct and independently fixed in the tibia with an interference screw anchor. For each specimen, the authors recorded ultimate load, yield load, stiffness, cyclic displacement, and mode of failure. Outcomes between groups were compared using the Student t test.Results:There was a 33% decrease in mean cyclic displacement in the specimens with reinforced grafts (reinforced vs control: 3.9 ± 0.7 vs 5.8 ± 1.5 mm; P = .001). The reinforced grafts also had a 22% higher mean ultimate load (921 ± 180 vs 717 ± 122 N; P = .008) and a 25% higher mean yield load (808 ± 201 vs 602 ± 155 N; P = .020). There was no significant difference in stiffness between the reinforced versus nonreinforced grafts (136 ± 16 vs 132 ± 18 N/mm; P = .617). Three of the 10 control specimens failed at the graft, compared with 1 of 10 reinforced grafts. All other constructs in both groups failed at the tibial fixation site.Conclusion:Suture tape reinforcement of soft tissue grafts significantly decreased cyclic displacement while significantly increasing ultimate and yield loads without increasing graft construct stiffness during biomechanical testing at time zero in a porcine animal model.Clinical Relevance:The improved biomechanical performance of suture tape–reinforced graft constructs could allow patients to participate in earlier advancement of aggressive rehabilitation and potentially reduce failure rates as graft remodeling progresses.

Allografts: Hand, wrist and forearm

Bone defects are a very common problem in hand surgery and in wrist surgery. Bone allografts may be used instead of autologous bone graft to avoid donor site morbidity. Flexor and extensor tendon injuries significantly impact a patient’s quality of life, resulting in significant functional deficits; soft tissue allografts may be used instead of autologous grafts as well.

Our Preferred Technique for Bone–Patellar Tendon–Bone Allograft Preparation

Anterior cruciate ligament (ACL) reconstruction is an increasingly common procedure as orthopaedic patients seek to remain active longer in life, resulting in more ligamentous knee injuries. Graft selection is at the forefront of decision making in knee reconstruction, with advantages and disadvantages to various grafts, including allograft to autograft. Although the gold standard for the ACL reconstruction of elite athletes and highly active patients has traditionally been bone–patellar tendon–bone autograft (BTB), this graft is not without its disadvantages, such as increased operative time, increased postoperative pain, potential for anterior knee pain, larger incision, violation of the extensor mechanism, and potentially kneeling pain. Soft tissue autografts (hamstring, quadriceps) offer a good alternative; however, they may be associated with higher rerupture rates, as well as associated donor site morbidity. Additionally, soft tissue allografts have a higher graft rupture rate. For this reason, it is the senior author’s preference to perform allograft ACL reconstruction with BTB allograft in appropriately selected patients. We describe our technique for an efficient and reproducible BTB allograft preparation.

Aseptically Processed Allograft Implantation: A Safe Strategy for Knee Ligament Reconstructions.

Postoperative infections after allograft implantation is a major concern in knee ligament reconstructions considering the theoretical risk of disease transmission and its potential severity. Here, we aimed to evaluate the postoperative infection rate after knee ligament reconstructions using aseptically processed allografts, and provide an overview of the allografts use in an academic tertiary hospital. A retrospective study was performed evaluating patients who underwent knee ligament reconstructions using aseptically processed allografts, including primary and revision surgeries, from 2005 to 2018. Demographic data, including the type of knee injury and trauma energy, and postoperative data were collected focusing on postoperative infections. Regarding these infected cases, further analyses were performed considering the presenting signs and symptoms, the isolated microorganism identified in culture, the time between graft implantation and diagnosis of infection (defined as acute, subacute, and late), and the need for graft removal. A total of 180 cases of ligament reconstructions were included. The mean follow-up was 8.2 (range: 2.1-15.6) years and the mean age at surgery was 34.1 (± 11.1) years. A total of 262 allografts were implanted in those 180 cases, 93 (35.5%) as bone plug allografts and 169 (64.5%) as soft tissue allografts. Common surgical indications included multiligament reconstruction (57.2%) and primary anterior cruciate ligament (ACL) reconstruction (15%). Seven cases (3.9%) presented postoperative infections. Knee pain (100%) and swelling (100%) were the most prevalent symptoms. Two cases (28.6%) presented sinus tract. Allografts were removed in two cases, the same cases that presented draining sinus (p = 0.04). High-energy trauma was the only statistically associated factor for infection (p = 0.04). No significant association between infection and the type of allograft (p > 0.99) or sex (p = 0.35) were observed. Four cases (57.1%) had monomicrobial staphylococcal infections. Based on that, the allograft-related infection rate was 1.7% (the remaining three infected cases). Nonirradiated, aseptically processed allografts have a low postoperative infection rate in knee ligament reconstructions, being a safe alternative for surgeries that require additional source, increased variety, and quantity of grafts.

Association Between Graft Choice and 6-Year Outcomes of Revision Anterior Cruciate Ligament Reconstruction in the MARS Cohort

Background: Although graft choice may be limited in the revision setting based on previously used grafts, most surgeons believe that graft choice for anterior cruciate ligament (ACL) reconstruction is an important factor related to outcome. Hypothesis: In the ACL revision setting, there would be no difference between autograft and allograft in rerupture rate and patient-reported outcomes (PROs) at 6-year follow-up. Study Design: Cohort study; Level of evidence, 2. Methods: Patients who had revision surgery were identified and prospectively enrolled in this cohort study by 83 surgeons over 52 sites. Data collected included baseline characteristics, surgical technique and pathology, and a series of validated PRO measures. Patients were followed up at 6 years and asked to complete the identical set of PRO instruments. Incidence of additional surgery and reoperation because of graft failure were also recorded. Multivariable regression models were used to determine the predictors (risk factors) of PROs, graft rerupture, and reoperation at 6 years after revision surgery. Results: A total of 1234 patients including 716 (58%) men were enrolled. A total of 325 (26%) underwent revision using a bone-patellar tendon-bone (BTB) autograft; 251 (20%), soft tissue autograft; 289 (23%), BTB allograft; 302 (25%), soft tissue allograft; and 67 (5%), other graft. Questionnaires and telephone follow-up for subsequent surgery information were obtained for 809 (66%) patients, while telephone follow-up was only obtained for an additional 128 patients for the total follow-up on 949 (77%) patients. Graft choice was a significant predictor of 6-year Marx Activity Rating Scale scores (P = .024). Specifically, patients who received a BTB autograft for revision reconstruction had higher activity levels than did patients who received a BTB allograft (odds ratio [OR], 1.92; 95% CI, 1.25-2.94). Graft rerupture was reported in 5.8% (55/949) of patients by their 6-year follow-up: 3.5% (16/455) of patients with autografts and 8.4% (37/441) of patients with allografts. Use of a BTB autograft for revision resulted in patients being 4.2 times less likely to sustain a subsequent graft rupture than if a BTB allograft were utilized (P = .011; 95% CI, 1.56-11.27). No significant differences were found in graft rerupture rates between BTB autograft and soft tissue autografts (P = .87) or between BTB autografts and soft tissue allografts (P = .36). Use of an autograft was found to be a significant predictor of having fewer reoperations within 6 years compared with using an allograft (P = .010; OR, 0.56; 95% CI, 0.36-0.87). Conclusion: BTB and soft tissue autografts had a decreased risk in graft rerupture compared with BTB allografts. BTB autografts were associated with higher activity level than were BTB allografts at 6 years after revision reconstruction. Surgeons and patients should consider this information when choosing a graft for revision ACL reconstruction.

Bioactivation of Bovine Bone Matrix and Collagen Scaffold Using Argon Plasma: In Vitro Study.

Bone graft materials and soft tissue allografts are widely used in clinical practice to counteract physiologic postextraction site tridimensional shrinkage. The aim of this study was to test if plasma of argon treatment could have a bioactivation effect on hard and soft tissue scaffolds in clinical usage. Forty-eight bovine bone matrix and porcine collagen samples were subdivided into two groups (test and control) of 12 samples each. The test group was treated with argon plasma (10 W, 1 bar for 12 minutes), while the control group was left untreated. Immediate cell adhesion and a proliferation assay at 72 hours were performed in the perfusion chamber of a bioreactor. Additionally, micro-CT analysis was performed on the treated and untreated scaffolds, before and after soaking in cell culture medium (four samples). Osteoblasts seeded on plasma-treated bone matrix significantly increased the adhesion level compared with the untreated sample (43,144.3 ± 12,442.9 vs 21,736 ± 77,27.1; P = .0083). However, 3-day proliferation tests could not achieve significant differences between groups (105,715.5 ± 21,751.5 vs 107,108.6 ± 19,343.4; P = .998). No differences were measured on fibroblast adhesion on the collagen matrix in both conditions. Plasma of argon treatment and soaking in cell culture medium did not affect the bone matrix samples. The structure of collagen matrix samples was unaltered after plasma treatment, but became enlarged after soaking. Plasma of argon may be useful to biofunctionalize bone grafts, although benefits seemed to disappear after 3 days. No biologic response was detected on collagen matrix scaffolds. In vivo studies are needed to draw final clinical conclusions.

Early Outcomes of Adolescent ACL Reconstruction With Hybrid Hamstring Tendon Autograft-Allograft Versus Hamstring Tendon Autograft Alone.

Background:Small-diameter semitendinosus-gracilis tendon autografts may be encountered intraoperatively during anterior cruciate ligament reconstruction (ACLR); these have been shown to be at increased risk of graft rupture. One option that surgeons have pursued to reduce the theoretical failure rate of these smaller-diameter grafts is augmenting them with allograft material, thereby forming a larger-diameter hybrid autograft-allograft construct.Purpose/Hypothesis:The purpose of this study was to compare outcomes in adolescent athletes of primary ACLR using a hybrid autologous hamstring tendon and soft tissue allograft construct versus ACLR using small-diameter hamstring tendon autograft. The hypothesis was that the hybrid hamstring autograft-allograft construct would provide superior short-term results.Study Design:Cohort study; Level of evidence, 3.Methods:We performed a retrospective analysis of 47 patients aged between 12 and 20 years who underwent hybrid graft ACLR (mean diameter, 9.1 mm) at a single institution. Electronic medical records including clinic notes, radiographic images, operative notes, and pathology reports were reviewed for study analysis. A control group of 64 patients who underwent small-diameter hamstring reconstruction (mean diameter, 7.1 mm) without allograft supplementation was compiled. Corresponding clinical, radiographic, and surgical characteristics were collected for the control group to allow for comparative analysis.Results:Mean follow-up was 2.7 years for the hybrid cohort and 2.3 years for the control group. Despite a significantly larger mean graft diameter in the hybrid group as compared with the control group (P < .001), no significant difference in retear rate was seen between cohorts (hybrid, 9%; control, 13%; P = .554). Patients with hybrid anterior cruciate ligament constructs also underwent a comparable number of reoperations overall (P = .838). Functionally, all patients with adequate follow-up returned to sports, with no significant difference in time to return to sports between the groups (P = .213). Radiographically, hybrid graft constructs did not undergo a significantly larger degree of tunnel lysis (P = .126).Conclusion:A cohort of adolescents with hybrid anterior cruciate ligament grafts was shown to have retear rates and overall clinical results comparable with those of a control group that received small-diameter hamstring tendon autografts alone.

Outcomes of chronic distal biceps reconstruction with tendon grafting: a matched comparison with primary repair.

BackgroundThe purpose of this analysis was to analyze outcomes of distal biceps reconstruction with soft tissue allograft in the setting of chronic, irreparable distal biceps ruptures. The outcomes of these cases were then compared with a matched cohort of distal biceps ruptures that were able to be repaired primarily.MethodsRetrospective review of an institutional elbow surgery database was conducted. All cases of distal biceps repairs were identified by Common Procedural Terminology, ICD-9, and ICD-10 codes from January 2009 to March 2018. A direct review of operative reports was then conducted to identify which cases required allograft reconstruction. After identification of this population, a 2:1 manually matched cohort of patients who underwent primary repair was generated using age, gender, body mass index, and age-adjusted Charlson Comorbidity Index. Finally, the allograft reconstruction and matched primary repair cohorts were compared for reoperation, range of motion, and patient-reported outcomes scores.ResultsThere were 46 male patients who underwent distal biceps reconstruction with allograft (14 Achilles tendon, 32 semitendinosus) and they were matched to 92 male patients that underwent primary distal biceps repair. Mean patient age (46.9 ± 10.3 vs. 47.0 ± 9.8 years, P = .95), BMI (31.3 ± 5.3 vs. 31.3 ± 4.8 kg/m2, P = .60), and Charlson Comorbidity Index (1.2 ± 1.1 vs. 1.3 ± 0.9, P = .64) were similar between allograft reconstruction and primary repair groups. Disability of the Arm, Shoulder and Hand score (7.4 ± 18.0 vs. 1.6 ± 4.1, P = .23), Mayo Elbow Performance Score (92.1 ± 19.7 vs. 97.3 ± 6.4, P = .36), and Oxford Elbow Score (43.4 ± 11.0 vs. 46.8 ± 3.2, P = .25) were not significantly different between groups at mean 5.1 years (range, 1.5-10.9 years) after surgery. There were 1 of 42 (2.2%) allograft patients who require revision compared with 3 of 92 (3.3%, P = .719) in the primary repair group. In addition, one primary repair required reoperation for scar tissue excision and lateral antebrachial cutaneous neurolysis. Final range of motion data (twelve-week follow-up) for the allograft reconstruction group was similar to primary repair group in flexion (136.1° ± 5.3° vs. 135.9° ± 2.7°, P = .81), extension (0.8° ± 2.9° vs. 0.4° ± 1.7°, P = .53), pronation (78.0° ± 9.0° vs. 76.4° ± 15.4°, P = .50), supination (77.4° ± 10.7° vs. 77.5° ± 11.9°, P = .96).ConclusionPatients who underwent distal biceps reconstruction with a graft had similar failure rates, reoperation rates, final range of motion, and patient-reported outcomes scores as those treated without a graft. Patients can be consulted that direct repair in the acute setting is preferred; however, even in the setting of a distal biceps reconstruction with graft augmentation, they can expect low complications and good functional results.

Principles of bone and tissue banking in Saudi Arabia: 10-year experience report.

The role of bone and tissue banking is well known to meet the ever-growing need of bone and soft tissue allografts. Strict guidelines have been established to ensure high standard and minimize complications related to bone transplantation. The Bone Bank in King Faisal Specialist Hospital and Research Centre (KFSH&RC), affiliated with the Saudi Council of Organ Transplantation, was inaugurated in 2010, and it has since been an integral part of the KFSH&RC organ retrieval team. The bank has a very strict regulations which were described. Between January 2010 and January 2020, there were 143 multi-organ donors (mean age: 36years, range: 24-55years). The total number of allografts used was 2191 which were utilized in 1047 patients. In this paper, we present our 10-year experience of administrative structure, donor and recipient testing protocols, allograft retrieval, processing procedures, and the internal audit safety arrangements. The utilization of allografts in various pathologies such as revision joint replacement, spine surgery, and tumor surgery is discussed with our results over a 10-year period.

Incidence and Predictors of Subsequent Surgery After Anterior Cruciate Ligament Reconstruction: A 6-Year Follow-up Study

Background: The cause of subsequent surgery after anterior cruciate ligament (ACL) reconstruction varies, but if risk factors for specific subsequent surgical procedures can be identified, we can better understand which patients are at greatest risk. Purpose: To report the incidence and types of subsequent surgery that occurred in a cohort of patients 6 years after their index ACL reconstruction and to identify which variables were associated with the incidence of patients undergoing subsequent surgery after their index ACL reconstruction. Study Design: Cohort study; Level of evidence, 2. Methods: Patients completed a questionnaire before their index ACL surgery and were followed up at 2 and 6 years. Patients were contacted to determine whether any underwent additional surgery since baseline. Operative reports were obtained, and all surgical procedures were categorized and recorded. Logistic regression models were constructed to predict which patient demographic and surgical variables were associated with the incidence of undergoing subsequent surgery after their index ACL reconstruction. Results: The cohort consisted of 3276 patients (56.3% male) with a median age of 23 years. A 6-year follow-up was obtained on 91.5% (2999/3276) with regard to information on the incidence and frequency of subsequent surgery. Overall, 20.4% (612/2999) of the cohort was documented to have undergone at least 1 subsequent surgery on the ipsilateral knee 6 years after their index ACL reconstruction. The most common subsequent surgical procedures were related to the meniscus (11.9%), revision ACL reconstruction (7.5%), loss of motion (7.8%), and articular cartilage (6.7%). Significant risk factors for incurring subsequent meniscus-related surgery were having a medial meniscal repair at the time of index surgery, reconstruction with a hamstring autograft or allograft, higher baseline Marx activity level, younger age, and cessation of smoking. Significant predictors of undergoing subsequent surgery involving articular cartilage were higher body mass index, higher Marx activity level, reconstruction with a hamstring autograft or allograft, meniscal repair at the time of index surgery, or a grade 3/4 articular cartilage abnormality classified at the time of index ACL reconstruction. Risk factors for incurring subsequent surgery for loss of motion were younger age, female sex, low baseline Knee injury and Osteoarthritis Outcome Score symptom subscore, and reconstruction with a soft tissue allograft. Conclusion: These findings can be used to identify patients who are at the greatest risk of incurring subsequent surgery after ACL reconstruction.

Revision Risk of Soft Tissue Allograft Versus Hybrid Graft After Anterior Cruciate Ligament Reconstruction

Background: When a harvested hamstring autograft is deemed by the surgeon to be of inadequate diameter, the options include using the small graft, using another autograft from a different site, augmenting with an allograft (hybrid graft), using a different configuration of the graft (eg, 5- or 6-stranded), or abandoning the autograft and using allograft alone. A small graft diameter is associated with a higher revision risk, and using another autograft site includes added harvest-site morbidity; therefore, use of a hybrid graft or an allograft alone may be appealing alternative options. Revision risk for hybrid graft compared with soft tissue allograft is not known. Purpose: To evaluate the risk for aseptic revision surgery after primary anterior cruciate ligament reconstruction (ACLR) using a soft tissue allograft compared with ACLR using a hybrid graft in patients 25 years and younger. Study Design: Cohort study; Level of evidence, 3. Methods: Data from a health care system’s ACLR registry were used to identify primary isolated unilateral ACLRs between 2009 and 2016 using either a hybrid graft (hamstring autograft with soft tissue allograft) or a soft tissue allograft alone. Multivariable Cox proportional hazards regression was used to evaluate risk for aseptic revision after ACLR according to graft used after adjustment for age, allograft processing, tunnel drilling technique, and region where the primary ACLR was performed. Results: The cohort included 2080 ACLR procedures; a hybrid graft was used for 479 (23.0%) ACLRs. Median follow-up time was 3.4 years (interquartile range, 1.8-5.1 years). The crude 2-year aseptic revision probability was 5.4% (95% CI, 4.3%-6.7%) for soft tissue allograft ACLR and 3.8% (95% CI, 2.3%-6.4%) for hybrid graft ACLR. After adjustment for covariates, soft tissue allograft ACLR had a higher risk of aseptic revision during follow-up compared with hybrid graft ACLR (hazard ratio, 2.00; 95% CI, 1.21-3.31; P = .007). Conclusion: Soft tissue allografts had a 2-fold higher risk of aseptic revision compared with hybrid graft after ACLR. Future studies evaluating the indications for using hybrid grafts and the optimal hybrid graft diameter is needed.

Revision Risk Of Soft Tissue Allograft Versus Hybrid Graft Following Anterior Cruciate Ligament Reconstruction

Objectives: Prior studies have found smaller hamstring autograft diameter to be associated with a higher revision risk following anterior cruciate ligament reconstruction (ACLR). Therefore, when a harvested hamstring autograft is deemed by the surgeon to be of inadequate diameter, the options include: using the small graft, using another autograft from a different site, augmenting with an allograft (hybrid graft), or abandoning the autograft and using allograft alone. Using another autograft site includes added harvest-site morbidity, therefore utilization of an allograft to augment the autograft (hybrid) or allograft alone may be an appealing alternative option. Revision risk for hybrid graft compared to soft tissue allograft in is not known. The purpose of our study was to determine the risk for aseptic revision following soft tissue allograft ACLR compared to hybrid graft ACLR in patients 25 years and younger. Methods: Data from a healthcare system’s ACLR registry was used to conduct a cohort study. Primary isolated unilateral ACLR from 2009-2016 using either a hybrid graft (hamstring autograft + soft tissue allograft) or soft tissue allograft alone were identified. Time-to-aseptic revision surgery following primary ACLR was the primary endpoint. Multivariable Cox proportional hazard regression was used to evaluate risk for aseptic revision according to graft utilization after adjustment for age, allograft processing, tunnel drilling technique, and region where the primary ACLR was performed. Analysis censored patients at the time lost to follow-up (healthcare plan termination or death) or the end of study follow-up. A sandwich covariance matrix estimator was used to account for clustering of ACLR at the surgeon level. Results: The cohort included 2080 ACLR performed by 161 surgeons at 42 healthcare centers. Soft tissue allograft was used for 1601 (77.0%) ACLR and hybrid graft for 478 (23.0%). For the soft tissue allograft ACLR group, mean age was 19.2 (standard deviation [SD]=3.5) years, 79.1% of allografts were irradiated or chemically processed, and 50.4% of femoral tunnels were through the trans-tibial technique. For the hybrid graft ACLR group, mean age was 18.4 (SD=3.3) years, 81.5% were irradiated or chemically processed, and 72.3% of femoral tunnels were through the trans-tibial technique. Median follow-up time was 3.4 years (interquartile range=1.8-5.1 years). The crude 2-year aseptic revision probability was 5.4% (95% confidence interval [CI]=4.3-6.7) for soft tissue allograft ACLR and 3.8% (95% CI=2.3-6.4) for hybrid ACLR. After adjustment for covariates, soft tissue allograft ACLR had a higher risk of aseptic revision during follow-up compared to hybrid graft ACLR (hazard ratio=2.00, 95% CI=1.21-3.31, p=0.007). Conclusion: Soft tissue allograft had twice the risk of aseptic revision compared to hybrid graft following ACLR. Based on our findings, when faced with a hamstring autograft that is deemed to have an inadequate diameter, augmenting it with allograft tendon may be preferred over abandoning it for an allograft alone. Future study evaluating the indications and the optimal hybrid graft diameter is needed.

Quantitative imaging of anterior cruciate ligament (ACL) graft demonstrates longitudinal compositional changes and relationships with clinical outcomes at 2 years after ACL reconstruction.

T1 ρ and T2 magnetic resonance imaging (MRI) may allow for a noninvasive assessment of ligamentization after anterior cruciate ligament (ACL) reconstruction. We hypothesized that ACL graft T1 ρ and T2 relaxation times would decrease over time, that T1 ρ and T2 relaxation times would be inversely correlated with Knee Osteoarthritis Outcome Scores (KOOS), and that T1 ρ and T2 values would be lower for autograft relative to allograft reconstruction. Thirty-nine patients (age: 30.5 ± 8.2 years) were followed prospectively after ACL reconstruction with hamstring autograft (N = 27) or soft-tissue allograft (N = 12). Magnetic resonance (MR) imaging and KOOS surveys were completed at 6, 12, 24, and 36 months after surgery. ACL graft was segmented to define T1 ρ and T2 relaxation times. Relaxation times were compared between time points with ANOVA tests. Log-transformed autograft and allograft relaxation times were compared with the Student t tests. The relationship between KOOS and relaxation times at 24 months was investigated with Spearman's rank correlation. ACL graft T1 ρ relaxation times were significantly higher at 6 months relative to 12 months (P = .042), 24 months (P < .001), and 36 months (P < .001). ACL graft T2 relaxation times were significantly higher at 6 months relative to 12 months (P = .036), 24 months (P < .001), and 36 months (P < .001). T1 ρ and T2 relaxation times were significantly lower for autograft reconstruction vs allograft reconstruction at 24 months postreconstruction. Two-year KOOS Sports, Pain, and Symptoms were significantly inversely correlated with T1 ρ and T2 relaxation times. T1 ρ and T2 sequences may offer a noninvasive method for monitoring ACL graft maturation that correlates with patient-reported knee function after ACL reconstruction.

Use of Allografts in Orthopaedic Surgery: Safety, Procurement, Storage, and Outcomes

The use of allografts has become a vital option for orthopaedic surgeons in the treatment of a variety of musculoskeletal lesions, ranging from osteochondral defects in the glenohumeral joint to meniscal deficiency in the young athlete. Nevertheless, barriers to treating a patient with an allograft-based procedure may arise from concerns over disease transmission, the navigation of tissue banks that supply allografts, the process of obtaining insurance approval, or optimal storage methods. This review serves to support orthopaedic surgeons in the incorporation of allografts into their practice by quelling these potential concerns. Fresh osteochondral allografts, fresh-frozen meniscal allografts, soft tissue allografts, and off-the-shelf cartilage products are the focus of this review amid broad overviews of allograft safety and tissue bank practices in the United States.

Arthroscopic Posterior Glenohumeral Capsular Augmentation With Gracilis Tendon Allograft

Recurrent shoulder instability complicated by capsular insufficiency due to underlying soft-tissue disorders or multiple prior failed surgical procedures poses a challenging surgical problem. Traditional capsulolabral soft-tissue reconstruction techniques are less effective in this setting, and bony procedures sacrifice normal anatomic relations. The described arthroscopic technique aims to prevent instability while maintaining range of motion through creation of a soft-tissue allograft “sling” augmenting the posterior glenohumeral capsule.