Allograft compared with autograft infection rates in primary anterior cruciate ligament reconstruction

Presoaking hamstring autograft with vancomycin does not jeopardize its biomechanical properties, including graft elongation, after cyclic loading

PURPOSE

Presoaking the graft with vancomycin before implantation has been shown to reduce the risk of postoperative infection after anterior cruciate ligament reconstruction (ACLR). However, the effects of presoaking on the graft biomechanical properties remain unclear. This study aimed to determine whether presoaking the graft with vancomycin affects the graft biomechanical properties and length after cyclic loading.

METHODS

Ten paired (20 specimens) gracilis and semitendinous tendons were harvested from fresh-frozen human cadaveric specimens. Two tendons were folded in half to make four strands, and the grafts were randomized into the vancomycin and control groups. The graft was exposed to the antibiotic solution for 15 min (5 mg/mL) and prepared by mixing 1 g of vancomycin with 200 mL of normal saline (NaCl 0.9%). The control group was soaked in normal saline for 15 min. The prepared grafts were attached to the actuator of a dynamic tensile-testing machine. All grafts were tested with 3000 cycles of cyclic loading followed by a pull-to-failure. The cyclic loading protocol consisted of position and load control blocks to simulate the graft in vivo in the postoperative phase after ACLR.

RESULTS

Presoaking in vancomycin did not jeopardize the biomechanical properties of the graft. In addition, presoaking with vancomycin did not elongate the grafts. No significant differences were found in the mean Young's modulus and the mean total elongation of the graft of the specimen between the vancomycin group and the control group.

CONCLUSION

Presoaking the graft with vancomycin jeopardized neither its biomechanical properties nor elongation even after cyclic loading in this in vitro study. It is suggested that vancomycin presoaking could be considered a safe and effective preventive measure for postoperative infections after ACLR.

LEVEL OF EVIDENCE

Not applicable.

Presoaking Grafts in Vancomycin Does Not Impair Graft-Bone Healing in a Rat Anterior Cruciate Ligament Reconstruction Model

BACKGROUND

The vancomycin presoaking technique (wherein grafts are treated with a vancomycin solution [VS] for anterior cruciate ligament reconstruction [ACLR]) reduces the infection rate after ACLR. However, the effects of this technique on graft-bone healing have not been fully elucidated.

PURPOSE

To investigate the effects of vancomycin presoaking on graft-bone healing in a rat ACLR model.

STUDY DESIGN

Controlled laboratory study.

METHODS

Long flexor digitorum longus tendons were obtained from 9 Wistar rats, and each was randomly allocated to the normal saline (NS) or VS groups. The grafts were immersed in sterile saline for 30 minutes in the NS group and in a 5-mg/mL VS in the VS group. The presence of time-zero graft bacterial contamination was confirmed, and the grafts were incubated in Fluidised Thioglycollate Broth for 2 weeks. ACLR was performed on the right knees of 65 male Wistar rats using the flexor digitorum longus tendons. Each graft was similarly treated. Biomechanical testing, micro-computed tomography, and histological evaluations were performed 4 and 12 weeks postoperatively.

RESULTS

The VS group showed significantly reduced graft contamination at time zero (P = .02). The mean maximum loads to failure were 13.7 ± 8.2 N and 11.6 ± 4.8 N in the NS and VS groups, respectively, at 4 weeks (P = .95); and 23.2 ± 13.2 N and 30.4 ± 18.0 N in the NS and VS groups, respectively, at 12 weeks (P = .35). Regarding micro-computed tomography, the mean bone tunnel volumes were 3.76 ± 0.48 mm3 and 4.40 ± 0.58 mm3 in the NS and VS groups, respectively, at 4 weeks (P = .41); and 3.51 ± 0.38 mm3 and 3.67 ± 0.35 mm3 in the NS and VS groups, respectively, at 12 weeks (P = .54). Histological semiquantitative examination revealed no clear between-group differences at any time point.

CONCLUSION

Presoaking grafts in vancomycin in a rat ACLR model demonstrated no discernible adverse effects on short- and midterm biomechanical, radiological, and histological investigations.

CLINICAL RELEVANCE

The findings provide guidance for surgeons when considering this technique.

Incidence, Common Pathogens, and Risk Factors for Infection after Primary Anterior Cruciate Ligament Reconstruction: A Systematic Review

We sought to assess the current literature to present a comprehensive summary of the incidence, common pathogens, and risk factors for infection after anterior cruciate ligament (ACL) reconstruction. PubMed, CINAHL, EMBASE, and Scopus databases were searched for relevant studies reporting on infection after ACL reconstruction. Two reviewers independently screened the extracted studies for adherence to inclusion and exclusion criteria. Studies were selected if they reported on the incidence of infection, pathogens cultured from infected knees, or risk factors for infection after primary ACL reconstruction. Exclusion criteria consisted of studies with fewer than 100 patients or studies that included revision ACL reconstruction. Fifty studies met the inclusion and exclusion criteria, reporting on a total of 316,214 ACL reconstructions. Included studies evaluated between 123 and 104,255 patients. The overall incidence of infection was 0.60% (0.15-2.44%). The most common pathogens were Staphylococcus aureus, S. epidermidis, and coagulase-negative Staphylococci. Five studies reported that the use of hamstring autograft was a statistically significant risk factor for infection after ACL reconstruction, thus making hamstring autograft the most commonly reported risk factor. Other reported risk factors included male sex, use of immuno-suppressive medications or intraarticular steroid injections, prior knee surgery, and diabetes. Systematic review of the literature revealed that infection after ACL reconstruction remains an infrequent event with an incidence of 0.60% (0.15-2.44%). Furthermore, the most common pathogens are from the Staphylococcus genus of bacteria, comprising 84% of all culture-positive infections. Multiple risk factors have been reported for ACL reconstruction; however, statistical significance varied across studies. Together, these findings may help guide physicians in the prevention and treatment of infection after ACL reconstruction.

Anterior Cruciate Ligament Reconstruction Using Autologous Hamstrings Augmented with Ligament Augmentation and Reconstruction Systems (LARS) or Synthetic Meshwork of LARS Compared with Four-Strand Hamstring Tendon Grafts Alone, a Prospective, Randomized Clinical Study with 2- to 8-Year Follow-Up

Purpose

To compare the long-term outcomes of anterior cruciate ligament (ACL) reconstruction using a four-strand hamstring tendon graft alone (hamstring group) or with synthetics (Ligament Augmentation and Reconstruction System, LARS group) or synthetic meshwork of LARS (meshwork group).

Methods

Patients who underwent ACL reconstruction using four-strand hamstring tendon grafts (hamstring group), autologous hamstrings augmented with the LARS (LARS group), or synthetic meshwork of LARS (meshwork group) were selected in this prospective randomized clinical study. Patient-reported outcome measures (PROMs) were obtained preoperatively; at 6, 12, and 18 months postoperatively; and at final follow-up between 3 and 8 years. Second-look arthroscopic findings were used to evaluate graft morphology based on graft tension, graft tear, and synovial coverage.

Results

A total of 141 consecutive patients underwent ACL reconstruction, 47 patients in each group, and 21 patients were lost to follow-up during the study period. At the 6-month follow-up, the IKDC scores and Lysholm scores were significantly better in the LARS group (P < 0.05). At the 6- and 12-month follow-ups, the KOS-ADLS, KOOS-activities of daily living and quality of life, NSARS scores, GRC scores, Tegner scores, and ACL-RSI scores were significantly better in the LARS group (P < 0.05). For the LARS group, hamstring group, and meshwork group, the cumulative failure rates were 8.5%, 12.8%, and 4.3%, respectively. Malposition of the femoral tunnel was significantly associated with cumulative failure (P < 0.05). There was no difference between the groups in other outcomes at any other time, including radiographic and arthroscopic outcomes.

Conclusions

ACL reconstruction using autologous hamstring augmented with LARS resulted in significantly better clinical scores with a faster return to sports and comparative side-to-side differences in graft laxity by 6 and 12 months follow-up. Despite these findings, no statistically significant differences were seen among the three patient groups in terms of objective outcomes and clinical scores at the 18-month, 3-year and 8-year follow-ups. Additionally, a malpositioned femoral tunnel was associated with graft failure.

Vancomycin presoak reduces infection in anterior cruciate ligament reconstruction: a systematic review and meta-analysis

PURPOSE

To compare the effect of vancomycin presoak treatment of grafts during anterior cruciate ligament reconstruction on the incidence of postoperative infection or septic arthritis.

METHODS

Studies published before May 3, 2022 investigating vancomycin presoak of grafts during anterior cruciate ligament reconstruction were searched in the PubMed and Cochrane Central Register of Controlled Trials. Studies were screened, and data on the incidence of postoperative infection or septic arthritis were extracted and included in the analysis.

RESULTS

Thirteen studies were included for analysis after search screening, yielding a total of 31,150 participants for analysis, of whom 11,437 received graft vancomycin presoak treatment, and 19,713 did not receive treatment. Participants who received vancomycin treatment had significantly lower infection rates (0.09% versus 0.74%; OR 0.17; 95% CI 0.10, 0.30; P < 0.00001).

CONCLUSION

Pre-soaking of the graft with vancomycin during ACL reconstruction reduced the incidence of postoperative infection and septic arthritis.

Risk factors for postoperative surgical site infections after anterior cruciate ligament reconstruction: a systematic review and meta-analysis

OBJECTIVES

The primary aim was to evaluate risk factors for surgical site infections after anterior cruciate ligament reconstruction (ACLR). The secondary aim was to investigate the surgical site infection incidence rate and the mean time to postoperative surgical site infection symptoms.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Embase and Web of Science were searched from database inception to September 2021 and updated in April 2022.

ELIGIBILITY CRITERIA

Quantitative, original studies reporting potential risk factors for surgical site infections after ACLR were included.

RESULTS

Twenty-three studies with 3871 infection events from 469 441 ACLRs met the inclusion criteria. Male sex (OR 1.78, p< 0.00001), obesity (OR 1.82, p=0.0005), tobacco use (OR 1.37, p=0.01), diabetes mellitus (OR 3.40, p=0.002), steroid use history (OR 4.80, p<0.00001), previous knee surgery history (OR 3.63, p=0.02), professional athlete (OR 4.56, p=0.02), revision surgery (OR 2.05, p=0.04), hamstring autografts (OR 2.83, p<0.00001), concomitant lateral extra-articular tenodesis (OR 3.92, p=0.0001) and a long operating time (weighted mean difference 8.12, p=0.005) were identified as factors that increased the risk of surgical site infections (superficial and deep) after ACLR. Age, outpatient or inpatient surgery, bone-patellar tendon-bone autografts or allografts and a concomitant meniscus suture did not increase the risk of surgical site infections. The incidence of surgical site infections after ACLR was approximately 1% (95% CI 0.7% to 1.2%). The mean time from surgery to the onset of surgical site infection symptoms was approximately 17.1 days (95% CI 13.2 to 21.0 days).

CONCLUSION

Male sex, obesity, tobacco use, diabetes mellitus, steroid use history, previous knee surgery history, professional athletes, revision surgery, hamstring autografts, concomitant lateral extra-articular tenodesis and a long operation time may increase the risk of surgical site infections after ACLR. Although the risk of surgical site infections after ACLR is low, raising awareness and implementing effective preventions for risk factors are priorities for clinicians to reduce the incidence of surgical site infections due to its seriousness.

Postoperative Infection after Anterior Cruciate Ligament Reconstruction: Prevention and Management

Infection following anterior cruciate ligament (ACL) reconstruction can be one of the most debilitating complications following ACL reconstruction. Its reported incidence is around 1%. Utilization of vancomycin for presoaking the graft is considered an established method for infection prevention. The role of other agents, such as gentamycin needs further investigation. Staphylococci are the predominant causative pathogens, while particular attention should be paid to fungal infections due to their long-standing, occult process. Recent data demonstrate that hamstrings autograft may be at an elevated risk of being contaminated leading to subsequent septic arthritis. Diagnosis is set by clinical and laboratory findings and is usually confirmed by intraoperative cultures. Treatment varies, mainly depending on the intraoperative assessment. Satisfactory outcomes have been reported with both graft retaining and removal, and the decision is made upon the arthroscopic appearance of the graft and the characteristics of the infection. Of note, early management seems to lead to superior results, while persistent infection should be managed with graft removal in an attempt to protect the articular cartilage and the knee function.

Advances in Regenerative Sports Medicine Research

Regenerative sports medicine aims to address sports and aging-related conditions in the locomotor system using techniques that induce tissue regeneration. It also involves the treatment of meniscus and ligament injuries in the knee, Achilles’ tendon ruptures, rotator cuff tears, and cartilage and bone defects in various joints, as well as the regeneration of tendon–bone and cartilage–bone interfaces. There has been considerable progress in this field in recent years, resulting in promising steps toward the development of improved treatments as well as the identification of conundrums that require further targeted research. In this review the regeneration techniques currently considered optimal for each area of regenerative sports medicine have been reviewed and the time required for feasible clinical translation has been assessed. This review also provides insights into the direction of future efforts to minimize the gap between basic research and clinical applications.

Factors Associated With an Intra-articular Infection After Anterior Cruciate Ligament Reconstruction: A Large Single-Institution Cohort Study

BACKGROUND

An intra-articular infection after anterior cruciate ligament (ACL) reconstruction (ACLR) is a rare complication but one with potentially devastating consequences. The rare nature of this complication raises difficulties in detecting risk factors associated with it and with worse outcomes after one has occurred.

PURPOSE

To (1) evaluate the association between an infection after ACLR and potential risk factors in a large single-center cohort of patients who had undergone ACLR and (2) assess the factors associated with ACL graft retention versus removal.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

All ACLR procedures performed at our institution between January 2010 and December 2018 were reviewed; a total of 11,451 procedures were identified. A retrospective medical record review was performed to determine the incidence of infections, patient and procedure characteristics associated with an infection, infection characteristics, incidence of ACL graft retention, and factors associated with the retention versus removal of an ACL graft. Multivariable logistic regression analysis was used to identify potential risk factors for an infection after ACLR.

RESULTS

Of the 11,451 ACLR procedures, 48 infections were identified (0.42%). Multivariable logistic regression analysis revealed revision ACLR (odds ratio [OR], 3.13 [95% CI, 1.55-6.32]; P = .001) and younger age (OR, 1.06 [95% CI, 1.02-1.10]; P = .001) as risk factors for an infection. Compared with bone-patellar tendon-bone autografts, both hamstring tendon autografts (OR, 4.39 [95% CI, 2.15-8.96]; P < .001) and allografts (OR, 5.27 [95% CI, 1.81-15.35]; P = .002) were independently associated with an increased risk of infections. Overall, 15 ACL grafts were removed (31.3%). No statistically significant differences besides the number of irrigation and debridement procedures were found for retained versus removed grafts, although some trends were identified (P = .054).

CONCLUSION

In a large single-center cohort of patients who had undergone ACLR and those with an infection after ACLR, patients with revision cases and younger patients were found to have a higher incidence of infection. The use of bone-patellar tendon-bone autografts was found to be associated with the lowest risk of infection after ACLR compared with both hamstring tendon autografts and allografts. Larger cohorts with a larger number of infection cases are needed to determine the factors associated with graft retention versus removal.

Evaluation of the Efficacy of Vancomycin-Soaked Autograft to Eliminate Staphylococcus aureus Contamination After Anterior Cruciate Ligament Reconstruction: Based on an Infected Rat Model

BACKGROUND

Vancomycin-soaked autograft application in anterior cruciate ligament reconstruction (ACLR) significantly reduces postoperative infection rates. However, the optimal vancomycin concentrations and time of vancomycin presoaking of autografts for preventing infection are still unknown.

PURPOSE

To evaluate the efficacy of vancomycin-soaked autografts in preventing infection in rats with ACLR.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 102 tendons of Wistar rats were harvested under sterile conditions from fresh cadaveric legs. Contamination with 2.0 × 10⁴ colony forming units per milliliter of Staphylococcus aureus and soaking in different vancomycin concentrations for different soaking times was performed in vitro. In vivo, after being contaminated with S. aureus and soaked with optimal vancomycin solution treatment and sterile saline, the grafts were implanted in rat knees to finish ACLR surgery. At 2, 4, and 12 weeks after surgery, samples were harvested to observe signs of infection and tendon-bone incorporation via general postoperative conditions, serum inflammatory markers, microbiological counting, knee radiographs, micro-computed tomography, histologic staining, scanning electron microscopy, and biomechanical testing.

RESULTS

Bacterial contamination was eliminated when at least 5 or 10 mg/mL of vancomycin was applied for 30 minutes in vitro. Rats in the vancomycin-soaked graft group (5 mg/mL of vancomycin for 30 minutes) showed no significant signs of infection and fewer positive cultures than did those without presoaking. The vancomycin-soaked graft group had reduced serum inflammatory markers, tissue scores, inflammatory reactions in the joint tissue, and radiographic evidence of periarticular osseous destruction compared with the control group. At postoperative week 12, the vancomycin-soaked graft group showed good outcomes in tendon-bone incorporation via micro-computed tomography, histologic staining, and biomechanical testing.

CONCLUSION

In a rat model of infection after ACLR, presoaking grafts in a 5-mg/mL vancomycin solution for 30 minutes could effectively prevent S. aureus contamination without affecting tendon-bone incorporation and knee function.

CLINICAL RELEVANCE

The present study could provide a specific solution for the use of vancomycin in the prevention of infection after ACLR clinically.

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.

Surgeon practice patterns for pre-soaking ACL tendon grafts in vancomycin: a survey of the ACL study group

PURPOSE

To survey members of The ACL study group to determine the current practice patterns surrounding the technique of pre-soaking ACL grafts in vancomycin.

METHODS

A web-based questionnaire was distributed to members of the ACL Study Group. Questions included the use of vancomycin solution for graft soaking during ACL reconstruction, their protocol for soaking the graft, vancomycin concentration utilized, graft choices, and concerns with the technique.

RESULTS

Sixty-six (57%) ACL surgeons completed the survey. Approximately one-third (37.9%) of respondents currently pre-soak their ACL grafts in vancomycin prior to implantation, with 60% of these surgeons being from Europe. Seventy-six percent have adopted this practice within the past 5 years. The majority of surgeons wrap the graft in a vancomycin-soaked gauze prior to implantation (56%), soak for a variable amount of time before implantation (56%), use a concentration of 5 mg/mL (68%), and soak hamstring grafts (92%). Concerns included the mechanical properties of the graft (35%), cost of vancomycin (23%), availability (12%), and antibiotic resistance (9%).

CONCLUSION

This survey demonstrates that 37.9% of ACL study group members currently utilize vancomycin to pre-soak ACL tendon grafts as a means to decrease post-operative infection risk, with the majority of surgeons having implemented this practice within the past 5 years. The biggest concern towards using vancomycin was the mechanical properties of the graft after soaking.

LEVEL OF EVIDENCE

IV.

Significantly Lower Infection Risk for Anterior Cruciate Ligament Grafts Presoaked in Vancomycin Compared With Unsoaked Grafts: A Systematic Review and Meta-analysis

PURPOSE

To compare postoperative infection rates following ACL reconstruction performed with grafts presoaked in vancomycin versus those without vancomycin.

METHODS

A systematic review was performed using PRISMA guidelines. PubMed, SCOPUS, and Cochrane Central Register of Controlled Trials were searched for therapeutic level I to III studies that compared outcomes of presoaking ACL grafts with vancomycin versus without vancomycin in human patients. Included graft types were tendon autografts or allografts, and included studies documented infection with a minimum follow-up of 30 days. Postoperative infection rates and knee-specific patient-reported outcome scores were extracted from each study and compared between groups. Study methodological quality was analyzed using the Methodological Index for Non-Randomized Studies (MINORS) and Modified Coleman Methodology Score (MCMS). Infection rates and retear rates were pooled and weighted for meta-analysis using a random-effects model. All P values were reported with an α level of 0.05 set as significant.

RESULTS

The initial search yielded 144 articles (44 duplicates, 100 screened, 29 full-text review). Ten articles (21,368 subjects [7,507 vancomycin and 13,861 no vancomycin], 67% males, mean ± standard deviation age 29.5 ± 1.5 years) were included and analyzed. Eight of the 10 studies included only autografts, with 94.5% of grafts being hamstring autografts. Soaking grafts in vancomycin resulted in significantly fewer infections (0.013% versus 0.77%; odds ratio 0.07; 95% confidence interval 0.03, 0.18; P < .001). Only 2 studies included patient-reported outcomes, and both demonstrated no difference in International Knee Documentation Committee scores 1 year after surgery for patients with grafts presoaked in vancomycin versus without vancomycin.

CONCLUSIONS

Soaking ACL tendon grafts with vancomycin before implantation is associated with a nearly 15 times decrease in odds of infection compared with grafts not soaked in vancomycin. Few studies investigated patient-reported outcomes and retear rates after soaking ACL grafts in vancomycin.

LEVEL OF EVIDENCE

III, systematic review of level III studies.

Effect of Vancomycin Soaking on Anterior Cruciate Ligament Graft Biomechanics

PURPOSE

To evaluate the effect of soaking of anterior cruciate ligament (ACL) grafts in vancomycin solution on graft biomechanical properties at the time of implantation.

METHODS

The central third of patellar tendons was harvested from mature bovine knees and prepared as a tendon-only graft or a bone-tendon-bone (BTB) graft. Tendons were wrapped in gauze soaked in vancomycin solution (VS) (5 mg/mL) or normal saline (NS) and left to stand for 30 minutes at room temperature, simulating graft exposure times in the operating room during ACL reconstruction. Tensile testing was carried out on a materials testing system with (1) low-magnitude loading (60 N at 3 mm/s) with repeated testing of tendon-only grafts; and (2) high-magnitude loading (600 N at 10 mm/min) of BTB grafts. For tendon-only grafts, specimens were first wrapped in NS-soaked gauze and underwent testing, with repeated testing performed after wrapping in gauze soaked in VS or buffered VS (pH 7.0). For BTB grafts, specimens were randomly assigned to treatment with VS or NS.

RESULTS

For tendon-only grafts, there was no difference in Young's modulus (YM) after soaking with VS soaking (baseline, 12.69 MPa; treatment, 16.07 ± 4.44 MPa; P = .99) or buffered VS (baseline, 12.45 ± 4.55 MPa; treatment, 15.56 ± 2.83 MPa; P = .99). For BTB grafts, there were no differences in elongation strain (VS, 46.8% ± 7.0%; NS, 31.5% ± 13.5%, P = .19) or YM (VS, 158.4 ± 15.8 MPa; NS, 158.5 ± 23.3 MPa, P = .99).

CONCLUSIONS

According to controlled biomechanical tests, vancomycin soaking of patellar tendon grafts does not adversely affect time-zero material properties.

CLINICAL RELEVANCE

This study suggests that vancomycin wrapping has no immediate adverse effects on the biomechanical properties of ACL grafts. Randomized controlled trials are warranted to validate the widespread use of vancomycin soaking of tendon grafts for infection prophylaxis during ACL reconstruction.

Clinical outcome after knee ligament reconstruction with tendon allografts

PURPOSE

The purpose of this study is to investigate the clinical outcome for patients after knee ligament reconstructions with allografts at a university hospital.

METHODS

A total of 33 patients received allografts for reconstructive knee surgery between 2007 and 2017. The follow up evaluation consisted of a clinical knee examination including evaluation of range of motion (ROM), lateral and medial laxity, the Lachman test, the Pivot shift test, the sag test, the posterior drawer test and checking for patellofemoral pain. The following patient-reported outcome measures (PROMs) were used; the Lysholm Function Score, the Tegner activity score, and the Knee injury and Osteoarthritis Outcome Score (KOOS).

RESULTS

Twenty-one (64%) patients were available for the follow-up evaluation and the mean follow-up time was 4.8 years. A total of 16 out of 21 patients had multiligament injuries of which the ACL was the ligament most frequently ruptured. At the time of follow-up, 14 out of 16 patients (87%) with ACL injury had Lachman test grade 0 or grade 1 + , and 12 out of 13 (92%) had a pivot shift grade 0 or 1 + . The mean Lysholm Score was 74. All mean KOOS subscale values were ≥ 59 at the follow-up. The preoperative Tegner activity score was 3 (range, 1-6) and 4 (range, 2-6) at follow up. There were no deep postoperative infections. A total of 19 out of 21 patients (90%) reported that they would have undergone surgery again had they known the clinical outcome in advance.

CONCLUSIONS

The patients improved from the preoperative score to the follow-up score in the knee-related Quality of Life (QoL) KOOS subscale. None of the patients were diagnosed with deep postoperative infections.

Gentamicin pre-soaking of hamstring autografts decreases infection rates in anterior cruciate ligament reconstruction

Aims

Graft infection following anterior cruciate ligament reconstruction (ACLR) may lead to septic arthritis requiring multiple irrigation and debridement procedures, staged revision operations, and prolonged courses of antibiotics. To our knowledge, there are no previous studies reporting on how gentamicin pre-soaking of hamstring grafts influences infection rates following ACLR. We set out to examine this in our study accordingly.

Methods

This retrospective study included 2,000 patients (1,156 males and 844 females) who underwent primary ACLR with hamstring autografts between 2007 to 2017. This included 1,063 patients who received pre-soaked saline hamstring grafts for ACLR followed by 937 patients who received pre-soaked gentamicin hamstring grafts for ACLR. All operative procedures were completed by a single surgeon using a standardized surgical technique. Medical notes were reviewed and data relating to the following outcomes recorded: postoperative infection, clinical progress, causative organisms, management received, and outcomes.

Results

Superficial wound infection developed in 14 patients (1.31 %) receiving pre-saline soaked hamstring grafts compared to 13 patients (1.38 %) receiving pre-gentamicin soaked hamstring grafts, and this finding was not statistically significant (p = 0.692). All superficial wound infections were treated with oral antibiotics with no further complications. There were no recorded cases of septic arthritis in patients receiving pre-gentamicin soaked grafts compared to nine patients (0.85%) receiving pre-saline soaked grafts, which was statistically significant (p = 0.004).

Conclusion

Pre-soaking hamstring autographs in gentamicin does not affect superficial infection rates but does reduce deep intra-articular infection rates compared to pre-soaking hamstring grafts in saline alone. These findings suggest that pre-soaking hamstring autografts in gentamicin provides an effective surgical technique for reducing intra-articular infection rates following ACLR.

Cite this article: Bone Jt Open 2021;2(1):66–71.

Soaking of Autologous Tendon Grafts in Vancomycin Before Implantation Does Not Lead to Tenocyte Cytotoxicity

BACKGROUND

Surgical site infections (SSIs) after anterior cruciate ligament (ACL) reconstruction procedures are an unfortunate complication. Soaking grafts in vancomycin before implantation has been reported to reduce the incidence of postoperative SSI after ACL reconstruction. There is potential for vancomycin to compromise graft integrity because of tenocyte toxicity.

PURPOSE

To examine the in vitro toxicity of varying doses of vancomycin on human tenocytes.

STUDY DESIGN

Controlled laboratory study.

METHODS

Human patellar tenocytes were isolated and expanded in vitro. Tenocytes in culture were exposed to vancomycin at 5 different concentrations (400, 1600, 3200, 6400, and 12,800 μg/mL) and 3 time intervals (2, 6, and 24 hours). The control for all series was tenocyte exposure to only culture medium for each time interval. After treatment, a 10% Cell Counting Kit-8 solution in cellular growth medium was applied to the cells to examine cytotoxicity. A live/dead assay was used to assess tenocyte viability through fluorescence microscopy and flow cytometry. Results were analyzed statistically using multivariable logistic regression models with Tukey honest significant difference post hoc tests.

RESULTS

Vancomycin did not cause significant changes in tenocyte viability after 2 and 6 hours of incubation at any concentration between 0 and 12,800 µg/mL. Incubation with vancomycin for 24 hours led to a significant decrease in cell viability at higher concentrations.

CONCLUSION

Tenocytes derived from human patellar tendons exposed to relatively high concentrations of vancomycin for short periods of time do not demonstrate significant cell death and toxicity.

CLINICAL RELEVANCE

Exposing tendons to vancomycin for a short period of time, such as before ACL reconstruction, is not likely to cause tenocyte toxicity because of vancomycin administration.

Graft Preparation with Intraoperative Vancomycin Decreases Infection After ACL Reconstruction: A Review of 1,640 Cases

BACKGROUND

Reported infection rates following anterior cruciate ligament (ACL) reconstruction are low, but infections are associated with high morbidity including reoperations and inferior clinical outcomes. The purpose of the current study was to investigate the rate of infection after ACL reconstruction with and without graft preparation with a vancomycin irrigant.

METHODS

All ACL reconstructions performed between May 2009 and August 2018 at a single academic institution were reviewed and categorized based on vancomycin use. Patients with <90-day follow-up, intraoperative graft preparation with an antibiotic other than vancomycin, or previous ipsilateral knee infection were excluded. Infection was defined as a return to the operating room for irrigation and debridement within 90 days after ACL reconstruction. Descriptive and inferential statistical analysis using t tests and Poisson regression were performed, with significance defined as p < 0.05.

RESULTS

In total, 1,640 patients (952 males; 58.0%) with a mean age (and standard deviation) of 27.7 ± 11.4 years underwent ACL reconstruction (1,379 primary procedures; 84.1%) and were included for analysis. Intraoperative vancomycin was used in 798 cases (48.7%), whereas 842 ACL reconstructions (51.3%) were performed without intraoperative vancomycin. In total, 11 reconstructions (0.7%) were followed by infection, which occurred in 10 (1.2%) of the patients in whom the graft was not soaked in vancomycin and in 1 (0.1%) of the patients in whom the graft was soaked in vancomycin (p = 0.032). Age (p = 0.571), sex (p = 0.707), smoking (p = 0.407), surgeon (p = 0.124), and insurance type (p = 0.616) were not associated with postoperative infection risk. Autograft use was associated with decreased infections (p = 0.045). There was an 89.4% relative risk reduction with the use of intraoperative vancomycin. An increased body mass index (BMI) (p = 0.029), increased operative time (p = 0.001), and the absence of ACL graft preparation with vancomycin (p = 0.032) independently predicted postoperative infection.

CONCLUSIONS

The use of vancomycin-soaked grafts was associated with a 10-fold reduction in infection after ACL reconstruction (0.1% versus 1.2%; p = 0.032). Other risk factors for infection after ACL reconstruction included increased BMI and increased operative time.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Allograft for knee ligament surgery: an American perspective

PURPOSE

Allografts are frequently use for ligamentous reconstruction at the knee. In the United States, tissue donation and distribution are highly regulated processes with thorough oversight from private and government entities. Allograft is widely available in the United States and allograft procurement is a large industry with varying procurement, sterilization, processing, and distribution procedures. It is important to understand allograft regulation and processing which may affect graft mechanical properties and biological graft integration.

METHODS

English-language literature, United States government and regulatory agency statues pertaining to allograft procurement, distribution, and usage were reviewed and the findings summarized.

RESULTS

During the processing of allograft, multiple factors including sterilization procedures, irradiation, storage conditions, and graft type all affect the biomechanical properties of the allograft tissue. Biological incorporation and ligamentization of allograft does occur, but at a slower rate compared with autograft. For ligamentous reconstruction around the knee, allograft offers shorter operative time, no donor-site morbidity, but has shown an increased risk for graft failure compared to autograft.

CONCLUSION

This article reviews the regulations on graft tissue within the United States, factors affecting the biomechanics of allograft tissue, differences in allograft tissue choices, and the use of allograft for anterior cruciate ligament reconstruction and multiligamentous knee injury reconstruction.

LEVEL OF EVIDENCE

V.

The use of allograft tendons in primary ACL reconstruction

PURPOSE

Graft choice in primary anterior cruciate ligament (ACL) reconstruction remains controversial. The use of allograft has risen exponentially in recent years with the attraction of absent donor site morbidity, reduced surgical time and reliable graft size. However, the published evidence examining their clinical effectiveness over autograft tendons has been unclear. The aim of this paper is to provide a current review of the clinical evidence available to help guide surgeons through the decision-making process for the use of allografts in primary ACL reconstruction.

METHODS

The literature in relation to allograft healing, storage, sterilisation, differences in surgical technique and rehabilitation have been reviewed in addition to recent comparative studies and all clinical systematic reviews and meta-analyses.

RESULTS

Early reviews have indicated a higher risk of failure with allografts due to association with irradiation for sterilisation and where rehabilitation programs and post-operative loading may ignore the slower incorporation of allografts. More recent analysis indicates a similar low failure rate for allograft and autograft methods of reconstruction when using non-irradiated allografts that have not undergone chemically processing and where rehabilitation has been slower. However, inferior outcomes with allografts have been reported in young (< 25 years) highly active patients, and also when irradiated or chemically processed grafts are used.

CONCLUSION

When considering use of allografts in primary ACL reconstruction, use of irradiation, chemical processing and rehabilitation programs suited to autograft are important negative factors. Allografts, when used for primary ACL reconstruction, should be fresh frozen and non-irradiated. Quantification of the risk of use of allograft in the young requires further evaluation.

LEVELS OF EVIDENCE

III.

Allograft tendons are a safe and effective option for revision ACL reconstruction: a clinical review

Revision anterior cruciate ligament reconstruction remains a challenge, especially optimising outcome for patients with a compromised knee where previous autogenous tissue has been used for reconstruction. Allograft tissue has become a recognized choice of graft for revision surgery but questions remain over the risks and benefits of such an option. Allograft tendons are a safe and effective option for revision ACL reconstruction with no higher risk of infection and equivalent failure rates compared to autografts provided that the tissue is not irradiated, or any irradiation is minimal. Best scenarios for use of allografts include revision surgery where further use of autografts could lead to high donor site morbidity, complex instability situations where additional structures may need reconstruction, and in those with clinical and radiologic signs of autologous tendon degeneration. A surgeon needs to be able to select the best option for the challenging knee facing revision ACL reconstruction, and in the light of current data, allograft tissue can be considered a suitable option to this purpose.Level of evidence IV.

Anterior cruciate ligament reconstruction without the use of a tourniquet

INTRODUCTION

Anterior cruciate ligament tears are a common ligamentous knee injury and are usually managed with arthroscopic reconstruction surgery using a tourniquet. The employment of a tourniquet in the management of an anterior cruciate ligament tear has been a debatable topic for some time. Here, we discuss our technique in the reconstruction of anterior cruciate ligament tears without the use of a tourniquet.

MATERIALS AND METHODS

We performed 26 anterior cruciate ligament reconstruction surgeries using hamstring grafts without the use of a tourniquet. The outcomes measured were pain using the visual analogue scale, knee swelling, range of movement and bleeding.

RESULTS

Using this technique, we have noted considerable reduction in knee swelling and pain. In addition, there was considerable improvement in the range of movement postoperatively, and there were no bleeding complications noted.

CONCLUSIONS

We consider ACL reconstruction without a tourniquet to be an excellent alternative to conventional reconstruction with the use of tourniquet.

Split Peroneus Longus Free Tendon Autograft Transplantation for the Treatment of Neglected Extensor Hallucis Longus Tendon Laceration: A Case Report

A neglected laceration of the extensor hallucis longus (EHL) tendon is rare. Retraction of the tendon ends often occurs when a laceration is neglected, leading to a substantial tendon deficit. A paucity of case reports is available describing the treatment of EHL laceration with a large area of gap secondary to retraction. Therefore, the treatment recommendations are limited. We present the case of a neglected EHL tendon laceration with a 10.5-cm gap in a healthy 22-year-old female. The EHL tendon laceration was repaired using a split peroneus longus tendon autograft that, to the best of our knowledge, has not been previously reported. At the 3-year follow-up evaluation, the patient retained full function of her hallux and was free of symptoms.

Meta-analysis of the Risk of Infections After Anterior Cruciate Ligament Reconstruction by Graft Type

BACKGROUND

An infection after anterior cruciate ligament (ACL) reconstruction is a relatively rare but challenging complication. There are no meta-analyses comparing the incidence of infections after ACL reconstruction with the various available graft choices.

PURPOSE

To compare the incidence of infections after ACL reconstruction with bone-patellar tendon-bone (BPTB) autografts compared with hamstring autografts, with a secondary aim of comparing the incidence of infections after reconstruction with autografts compared with allografts.

STUDY DESIGN

Meta-analysis.

METHODS

A systematic review was performed to identify level 1 and 2 studies that reported the incidence of infections by graft type after ACL reconstruction. Studies that evaluated patients undergoing primary ACL reconstruction with an autograft, allograft, or combination of autograft and allograft and reported the number of postoperative infections by graft type utilized were considered for inclusion. Studies were excluded if they included revision ACL reconstruction or did not specify the number of infections by graft type. Study findings were reviewed, and meta-analysis was performed when data were sufficiently homogeneous.

RESULTS

Twenty-one studies meeting criteria were identified from the literature review. Meta-analysis revealed a significant difference in the incidence of deep infections between BPTB autografts and hamstring autografts, with the BPTB group displaying a 77% lower incidence of infections compared with the hamstring group (relative risk [RR], 0.23; 95% CI, 0.097-0.54). The incidence of infections was 66% lower with BPTB autografts compared with all other graft types, with a pooled RR of 0.33 (95% CI, 0.15-0.71). There was no significant difference in the incidence of infections after ACL reconstruction with autografts compared with allografts (RR, 1.035; 95% CI, 0.589-1.819).

CONCLUSION

The findings of this meta-analysis demonstrate a significantly lower incidence of deep infections after ACL reconstruction with BPTB autografts compared with hamstring autografts but not compared with allografts.

CLINICAL RELEVANCE

Although the overall infection rate after ACL reconstruction is relatively low, the significantly higher rate of infections with hamstring autografts compared with BPTB autografts should be a consideration when discussing graft choices for ACL reconstruction.

Risk of Infection After Allograft Anterior Cruciate Ligament Reconstruction: Are Nonprocessed Allografts More Likely to Get Infected? A Cohort Study of Over 10,000 Allografts

BACKGROUND

Allograft tissue is frequently used in anterior cruciate ligament reconstruction (ACLR). It is often irradiated and/or chemically processed to decrease the risk of disease transmission, but some tissue is aseptically harvested without further processing. Irradiated and chemically processed allograft tissue appears to have a higher risk of revision, but whether this processing decreases the risk of infection is not clear.

PURPOSE

To determine the incidence of deep surgical site infection after ACLR with allograft in a large community-based sample and to evaluate the association of allograft processing and the risk of deep infection.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

The authors conducted a cohort study using the Kaiser Permanente Anterior Cruciate Ligament Reconstruction Registry. Primary isolated unilateral ACLR with allograft were identified from February 1, 2005 to September 30, 2015. Ninety-day postoperative deep infections were identified via an electronic screening algorithm and then validated through chart review. Logistic regression was used to evaluate the likelihood of 90-day postoperative deep infection per allograft processing method: processed (graft treated chemically and/or irradiated) or nonprocessed (graft not irradiated or chemically processed).

RESULTS

Of 10,190 allograft cases, 8425 (82.7%) received a processed allograft, and 1765 (17.3%) received a nonprocessed allograft. There were 15 (0.15%) deep infections during the study period: 4 (26.7%) coagulase-negative Staphylococcus, 4 (26.7%) methicillin-sensitive Staphylococcus aureus, 1 (6.7%) Peptostreptococcus micros, and 6 (40.0%) with no growth. There was no difference in the likelihood for 90-day deep infection for processed versus nonprocessed allografts (odds ratio = 1.36, 95% CI = 0.31-6.04).

CONCLUSION

The overall incidence of deep infection after ACLR with allograft tissue was very low (0.15%), suggesting that the methods currently employed by tissue banks to minimize the risk of infection are effective. In this cohort, no difference in the likelihood of infection between processed and nonprocessed allografts could be identified.

Risk Factors for Surgical Site Infections Following Anterior Cruciate Ligament Reconstruction

OBJECTIVE To determine the effect of graft choice (allograft, bone-patellar tendon-bone autograft, or hamstring autograft) on deep tissue infections following anterior cruciate ligament (ACL) reconstructions. DESIGN Retrospective cohort study. SETTING AND POPULATION Patients from 6 US health plans who underwent ACL reconstruction from January 1, 2000, through December 31, 2008. METHODS We identified ACL reconstructions and potential postoperative infections using claims data. A hierarchical stratified sampling strategy was used to identify patients for medical record review to confirm ACL reconstructions and to determine allograft vs autograft tissue implanted, clinical characteristics, and infection status. We estimated infection rates overall and by graft type. We used logistic regression to assess the association between infections and patients' demographic characteristics, comorbidities, and choice of graft. RESULTS On review of 1,452 medical records, we found 55 deep wound infections. With correction for sampling weights, infection rates varied by graft type: 0.5% (95% CI, 0.3%-0.8%) with allografts, 0.6% (0.1%-1.5%) with bone-patellar tendon-bone autografts, and 2.5% (1.9%-3.1%) with hamstring autograft. After adjusting for potential confounders, we found an increased infection risk with hamstring autografts compared with allografts (odds ratio, 5.9; 95% CI, 2.8-12.8). However, there was no difference in infection risk among bone-patellar tendon-bone autografts vs allografts (odds ratio, 1.2; 95% CI, 0.3-4.8). CONCLUSIONS The overall risk for deep wound infections following ACL reconstruction is low but it does vary by graft type. Infection risk was highest in hamstring autograft recipients compared with allograft recipients and bone-patellar tendon-bone autograft recipients. Infect Control Hosp Epidemiol 2016;37:827-833.

"Proprietary Processed" Allografts: Clinical Outcomes and Biomechanical Properties in Anterior Cruciate Ligament Reconstruction

BACKGROUND

The processing of allograft tissues in anterior cruciate ligament (ACL) reconstruction continues to be controversial. While high-dose irradiation of grafts has received scrutiny for high failure rates, lower dose irradiation and "proprietary-based" nonirradiated sterilization techniques have become increasingly popular, with little in the literature to evaluate their outcomes. Recent studies have suggested that the specifics of allograft processing techniques may be a risk factor for higher failure rates.

PURPOSE

To assess these proprietary processes and their clinical outcomes and biomechanical properties.

STUDY DESIGN

Systematic review.

METHODS

A systematic review was performed using searches of PubMed, EMBASE, Google Scholar, and Cochrane databases. English-language studies were identified with the following search terms: "allograft ACL reconstruction" (title/abstract), "novel allograft processing" (title/abstract), "allograft anterior cruciate ligament" (title/abstract), "anterior cruciate ligament allograft processing" (title/abstract), or "biomechanical properties anterior cruciate ligament allograft" (title/abstract). Duplicate studies, studies not providing the allograft processing technique, and those not containing the outcomes of interest were excluded. Outcomes of interest included outcome scores, complication and failure rates, and biomechanical properties of the processed allografts.

RESULTS

Twenty-four studies (13 clinical, 11 biomechanical) met inclusion criteria for review. No demonstrable difference in patient-reported outcomes was appreciated between the processing techniques, with the exception of the Tutoplast process. The clinical failure rate of the Tutoplast process was unacceptably high (45% at 6 years), but no other difference was found between other processing techniques (BioCleanse: 5.4%; AlloTrue: 5.7%; MTF: 6.7%). Several studies did show an increased failure rate, but these studies either combined processing techniques or failed to delineate enough detail to allow a specific comparison for this study. The biomechanical studies showed overall maintenance of satisfactory biomechanical properties throughout multiple testing modes with normalization to the percentage of control specimens.

CONCLUSION

A comparison of proprietary allograft processing techniques is difficult because of the variability and lack of specificity of reporting in the current literature. Among the available literature, except for the Tutoplast process, no notable differences were found in the clinical outcomes or biomechanical properties. Future study with a longer follow-up is necessary to determine the role and limitations of these grafts in the clinical setting.

Management of septic arthritis after arthroscopic anterior cruciate ligament reconstruction using a standard surgical protocol

BACKGROUND

To report the incidence of septic arthritis after anterior cruciate ligament (ACL) reconstruction and management of this complication using a specific treatment protocol.

METHODS

All primary ACL reconstructions performed in our institution between January 2002 and January 2014 were included in this study. Time to presentation, clinical symptoms, and culture results of all infected patients were analyzed. According to our protocol, an arthroscopic debridement and irrigation of the knee joint was performed immediately after a diagnosis of infection was made. In case of recurrence, knee irrigation with hardware and graft removal and later re-implantation was performed. Patients were evaluated with the Lysholm knee score, International Knee Documentation Committee (IKDC) Form, KT 1000 arthrometer and radiographic evaluation.

RESULTS

Postoperative septic arthritis occurred in seven of 1242 patients (0.56%). After initial arthroscopic debridement, infection recurred in six out of seven cases (85%). Graft and hardware removal was performed in these patients. Graft re-implantation was performed in four patients at an average five months after infection. At the final follow-up (mean 6.3years) all patients had full range of motion, while in patients with graft re-implantation the mean Lysholm score was 92, and the mean IKDC score was 87. Radiographs demonstrated that three patients had normal knees and one patient had a grade one, knee arthritis according to Kellgren-Lawrence classification.

CONCLUSIONS

Management of septic arthritis after ACL reconstruction using a specific surgical protocol which includes graft removal in case of infection recurrence with later re-implantation, can provide good and excellent results.

LEVEL OF EVIDENCE

Level IV, case series.

Primary anterior cruciate ligament reconstruction: perioperative considerations and complications

Anterior cruciate ligament (ACL) injuries are among the most commonly studied orthopaedic injuries. Despite having an excellent prognosis, complications do occur. The timely recognition and management of complications is imperative to ensure the success of reconstruction. Avoiding such complications requires thorough preoperative planning, proficient technical skills to properly manage intraoperative complications, and an extensive knowledge of possible postoperative complications.

A Biomechanical Comparison of Allograft Tendons for Ligament Reconstruction

BACKGROUND

Allograft tendons are frequently used for ligament reconstruction about the knee, but they entail availability and cost challenges. The identification of other tissues that demonstrate equivalent performance to preferred tendons would improve limitations. Hypothesis/Purpose: We compared the biomechanical properties of 4 soft tissue allograft tendons: tibialis anterior (TA), tibialis posterior (TP), peroneus longus (PL), and semitendinosus (ST). We hypothesized that allograft properties would be similar when standardized by the looped diameter.

STUDY DESIGN

Controlled laboratory study.

METHODS

This study consisted of 2 arms evaluating large and small looped-diameter grafts: experiment A consisted of TA, TP, and PL tendons (n = 47 each) with larger looped diameters of 9.0 to 9.5 mm, and experiment B consisted of TA, TP, PL, and ST tendons (n = 53 each) with smaller looped diameters of 7.0 to 7.5 mm. Each specimen underwent mechanical testing to measure the modulus of elasticity (E), ultimate tensile force (UTF), maximal elongation at failure, ultimate tensile stress (UTS), and ultimate tensile strain (UTε).

RESULTS

Experiment A: No significant differences were noted among tendons for UTF, maximal elongation at failure, and UTϵ. UTS was significantly higher for the PL (54 MPa) compared with the TA (44 MPa) and TP (43 MPa) tendons. E was significantly higher for the PL (501 MPa) compared with the TP (416 MPa) tendons. Equivalence testing showed that the TP and PL tendon properties were equivalent or superior to those of the TA tendons for all outcomes. Experiment B: All groups exhibited a similar E. UTF was again highest in the PL tendons (2294 N) but was significantly different from only the ST tendons (1915 N). UTϵ was significantly higher for the ST (0.22) compared with the TA (0.19) and TP (0.19) tendons. Equivalence testing showed that the TA, TP, and PL tendon properties were equivalent or superior to those of the ST tendons.

CONCLUSION

Compared with TA tendons, TP and PL tendons of a given looped diameter exhibited noninferior initial biomechanical strength and stiffness characteristics. ST tendons were mostly similar to TA tendons but exhibited a significantly higher elongation/UTϵ and smaller cross-sectional area. For smaller looped-diameter grafts, all tissues were noninferior to ST tendons. In contrast to previous findings, PL tendons proved to be equally strong.

CLINICAL RELEVANCE

The results of this study should encourage surgeons to use these soft tissue allografts interchangeably, which is important as the number of ligament reconstructions performed with allografts continues to rise.

No infections in 1300 anterior cruciate ligament reconstructions with vancomycin pre-soaking of hamstring grafts

PURPOSE

To investigate the pre-soaking of hamstring grafts in topical vancomycin, in addition to IV prophylaxis, during anterior cruciate ligament (ACL) reconstruction to reduce the incidence of post-operative infection, and to describe an evidence-based diagnostic and treatment algorithm to facilitate early diagnosis and appropriate management of possible knee sepsis post-operatively after ACL reconstruction.

METHODS

This study is a controlled observational series comprising of 1585 individuals who underwent ACL reconstruction over a 13-year period. All surgeries were performed by a single surgeon at the same hospital. Group 1 consisted of 285 patients who received pre-operative IV antibiotics without topical graft pre-soaking. Group 2 consisted of 1300 individuals who received IV antibiotics and graft pre-soaking in a vancomycin solution of 5 mg/mL.

RESULTS

In group 1, a total of four patients suffered a post-operative joint infection (1.4 %). Three out of the four were culture positive for Staphylococcus species. The fourth was culture negative but was managed as an acute infection. Group 2 suffered no post-operative infections (0 %). Statistical analysis of the vancomycin pre-soak with IV antibiotics group, compared with IV antibiotics-alone group, revealed a significantly reduced post-operative infection rate using a Fisher's exact test (P = 0.0011) and Chi-square test with Yates' correction (P = 0.0003).

CONCLUSIONS

Pre-soaking of hamstrings grafts with topical vancomycin reduced the rate of post-operative infection when compared to IV antibiotics alone. This technique should be utilised by surgeons to reduce the overall incidence of knee sepsis post-ACL reconstruction.

LEVEL OF EVIDENCE

III.

Surgical Technique Trends in Primary ACL Reconstruction from 2007 to 2014

BACKGROUND

The surgical technique for anterior cruciate ligament (ACL) reconstruction has evolved as a result of improved understanding of ligament biomechanics, anatomy, device development, and failed reconstructions. Studies on surgical technique preferences have been limited to surgeon surveys, which are subject to selection and recall bias. The purpose of this study was to evaluate ACL reconstruction surgical technique and yearly revision rate trends in a community-based setting.

METHODS

A population-based epidemiological study was conducted using data on primary ACL reconstruction procedures registered in an ACL reconstruction registry from 2007 to 2014. Changes in the incidence rates of different types of femoral tunnel drilling methods, different types of grafts and graft fixation, and revisions were studied. Adjusted incidence rate ratios (IRRs) are provided.

RESULTS

Of the 21,686 ACL reconstructions studied, 72.4% were performed by sports medicine fellowship-trained surgeons. The incidence rate of femoral tunnel drilling via a tibial tunnel decreased at an adjusted rate of 26% per year (IRR = 0.74, 95% confidence interval [CI] = 0.71 to 0.78), from 56.4% to 17.6% during the study period. The incidence rate of medial portal drilling increased from 41.3% to 65.1% at an adjusted rate of 11% per year (IRR = 1.11, 95% CI = 1.09 to 1.13), and the incidence rate of drilling through a lateral approach increased from 2.3% to 17.3% at an adjusted rate of 53% per year (IRR = 1.53, 95% CI = 1.39 to 1.67). There was no change in the use of hamstring autograft, bone-patellar tendon-bone autograft, or tibial tendon allograft. Use of first-generation bioabsorbable femoral and tibial fixation decreased for all graft types. For soft-tissue grafts, usage of suspensory metal femoral fixation increased 12% to 13% per year (IRR = 1.12, 95% CI = 1.09 to 1.15 for tibial tendon grafts; IRR = 1.13, 95% CI = 1.10 to 1.15 for hamstring grafts). For bone-patellar tendon-bone autografts, the use of femoral fixation with interference biocomposite screws increased 7% per year (IRR = 1.07, 95% CI = 1.04 to 1.10). On the tibial side, utilization of biocomposite screws increased for all graft types. No association was found between revision rate and the year of the primary operation.

CONCLUSIONS

Surgeons changed their femoral tunnel drilling technique over the study period, whereas the incidence rates of specific graft utilization remained stable. There has been a shift away from first-generation bioabsorbable fixation and increasing use of biocomposite fixation across all graft types. Early cumulative revision rates remained stable.

An audit of consent for allograft use in elective orthopaedic surgery

Introduction Patients receiving musculoskeletal allografts may be at risk of postoperative infection. The General Medical Council guidelines on consent highlight the importance of providing patients with the information they want or need on any proposed investigation or treatment, including any potential adverse outcomes. With the increased cost of defending medicolegal claims, it is paramount that adequate, clear informed patient consent be documented. Methods We retrospectively examined the patterns of informed consent for allograft bone use during elective orthopaedic procedures in a large unit with an onsite bone bank. The initial audit included patients operated over the course of 1 year. Following a feedback session, a re-audit was performed to identify improvements in practice. Results The case mix of both studies was very similar. Revision hip arthroplasty surgery constituted the major subgroup requiring allograft (48%), followed by foot and ankle surgery (16.3%) and revision knee arthroplasty surgery (11.4%) .On the initial audit, 17/45 cases (38%) had either adequate preoperative documentation of the outpatient discussion or an appropriately completed consent form on the planned use of allograft. On the re-audit, 44/78 cases (56%) had adequate pre-operative documentation. There was little correlation between how frequently a surgeon used allograft and the adequacy of consent (Correlation coefficient -0.12). Conclusions Although the risk of disease transmission with allograft may be variable, informed consent for allograft should be a routine part of preoperative discussions in elective orthopaedic surgery. Regular audit and feedback sessions may further improve consent documentation, alongside the targeting of high volume/low compliance surgeons.

Autograft Versus Allograft Anterior Cruciate Ligament Reconstruction: A Prospective, Randomized Clinical Study With a Minimum 10-Year Follow-up

BACKGROUND

The use of allografts for anterior cruciate ligament (ACL) reconstruction in young athletes is controversial. No long-term results have been published comparing tibialis posterior allografts to hamstring autografts.

PURPOSE

To evaluate the long-term results of primary ACL reconstruction using either an allograft or autograft.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

From June 2002 to August 2003, patients with a symptomatic ACL-deficient knee were randomized to receive either a hamstring autograft or tibialis posterior allograft. All allografts were from a single tissue bank, aseptically processed, and fresh-frozen without terminal irradiation. Graft fixation was identical in all knees. All patients followed the same postoperative rehabilitation protocol, which was blinded to the therapists. Preoperative and postoperative assessments were performed via examination and/or telephone and Internet-based questionnaire to ascertain the functional and subjective status using established knee metrics. The primary outcome measures were graft integrity, subjective knee stability, and functional status.

RESULTS

There were 99 patients (100 knees); 86 were men, and 95% were active-duty military. Both groups were similar in demographics and preoperative activity level. The mean and median ages of both groups were identical at 29 and 26 years, respectively. Concomitant meniscal and chondral pathologic abnormalities, microfracture, and meniscal repair performed at the time of reconstruction were similar in both groups. At a minimum of 10 years (range, 120-132 months) from surgery, 96 patients (97 knees) were contacted (2 patients were deceased, and 1 was unable to be located). There were 4 (8.3%) autograft and 13 (26.5%) allograft failures that required revision reconstruction. In the remaining patients whose graft was intact, there was no difference in the mean Single Assessment Numeric Evaluation, Tegner, or International Knee Documentation Committee scores.

CONCLUSION

At a minimum of 10 years after ACL reconstruction in a young athletic population, over 80% of all grafts were intact and had maintained stability. However, those patients who had an allograft failed at a rate over 3 times higher than those with an autograft.

Functional outcome of septic arthritis after anterior cruciate ligament surgery

PURPOSE

Septic arthritis is a rare complication after cruciate ligament surgery. The lack of conclusive evidence makes it difficult to obtain a consensus concerning the best treatment option.

METHODS

From June 1993 to May 2010, 31 patients met the inclusion criteria for this prospective case series. The average age at ACL injury was 33.5 years. Treatment protocol was based on the grade of infection. Options included arthroscopic treatment for infections of Gaechter grades 1 and 2 or arthrotomy for infections of grades 3 and 4. Graft retention was decided based on the clinical findings. The setting was a specialized trauma hospital. Follow-up included International Knee Documentation Committee (IKDC) forms, Tegner score, and Lysholm scores at a mean of six years (71 months; range, 13-140) after treatment.

RESULTS

In all cases, treatment of infection was successful; overall, a mean of 2.6 operations were required. In eight cases, it was possible to salvage the graft. The Tegner activity level before the knee injury was 6.5 points. At follow-up, the average score was 4.5 points. The postoperative subjective IKDC score averaged 63. The mean Lysholm score was 63.9. On clinical examination, a mean extension deficit of 2.5° and a mean maximum flexion of 121° were found. In the single-legged hop test, a mean capacity of 68% compared with the uninjured side was measured.

CONCLUSION

The stage-adapted procedure gives reliable results for septic arthritis after ACL surgery. There were no recurrences of septic arthritis or bone infection. Early infection can be managed arthroscopically with satisfactory results. More advanced infections should be addressed with a more radical approach. In conclusion, functional outcome in most of the presented cases was only fair compared with results from ACL surgery not complicated by infection.

The utility of claims data for infection surveillance following anterior cruciate ligament reconstruction

OBJECTIVE

To explore the feasibility of identifying anterior cruciate ligament (ACL) allograft implantations and infections using claims.

DESIGN

Retrospective cohort study.

METHODS

We identified ACL reconstructions using procedure codes at 6 health plans from 2000 to 2008. We then identified potential infections using claims-based indicators of infection, including diagnoses, procedures, antibiotic dispensings, specialty consultations, emergency department visits, and hospitalizations. Patients' medical records were reviewed to determine graft type, validate infection status, and calculate sensitivity and positive predictive value (PPV) for indicators of ACL allografts and infections.

RESULTS

A total of 11,778 patients with codes for ACL reconstruction were identified. After chart review, PPV for ACL reconstruction was 96% (95% confidence interval [CI], 94%-97%). Of the confirmed ACL reconstructions, 39% (95% CI, 35%-42%) used allograft tissues. The deep infection rate after ACL reconstruction was 1.0% (95% CI, 0.7%-1.4%). The odds ratio of infection for allografts versus autografts was 0.41 (95% CI, 0.19-0.78). Sensitivity of individual claims-based indicators for deep infection after ACL reconstruction ranged from 0% to 75% and PPV from 0% to 100%. Claims-based infection indicators could be combined to enhance sensitivity or PPV but not both.

CONCLUSIONS

While claims data accurately identify ACL reconstructions, they poorly distinguish between allografts and autografts and identify infections with variable accuracy. Claims data could be useful to monitor infection trends after ACL reconstruction, with different algorithms optimized for different surveillance goals.

Graft infection following arthroscopic anterior cruciate ligament reconstruction: a report of four cases

Septic arthritis following arthroscopic anterior cruciate ligament reconstruction (ACL) is a rare complication and associated with severe morbidity. Its risk factors include (1) concomitant procedures during the reconstruction, (2) previous knee surgery, (3) allograft usage, (4) peri-operative wound contamination, and (5) presence of intra-articular foreign bodies. We present a series of 3 men and one woman aged 22 to 35 years who developed septic arthritis following ACL reconstruction. The risk factors identified were local infection (n=2), previous ipsilateral knee surgery (n=2), and the use of an allograft (n=1). All patients underwent emergency knee washout and debridement with graft retention within 24 hours, together with a course of intravenous antibiotic therapy. All the patients achieved eradication of their infections (with intact ACL grafts) and satisfactory functional outcome at a mean follow-up of 32 (range, 25-45) months.

Infections in anterior cruciate ligament reconstruction

Context:

Anterior cruciate ligament (ACL) reconstruction is a safe, common, and effective method of restoring stability to the knee after injury, but evolving techniques of reconstruction carry inherent risk. Infection after ACL reconstruction, while rare, carries a high morbidity, potentially resulting in a poor clinical outcome.

Evidence Acquisition:

Data were obtained from previously published peer-reviewed literature through a search of the entire PubMed database (up to December 2012) as well as from textbook chapters.

Results:

Treatment with culture-specific antibiotics and debridement with graft retention is recommended as initial treatment, but with persistent infection, consideration should be given to graft removal. Graft type likely has no effect on infection rates.

Conclusion:

The early diagnosis of infection and appropriate treatment are necessary to avoid the complications of articular cartilage damage and arthrofibrosis.

Post-operative complications following primary ACL reconstruction using allogenic and autogenic soft tissue grafts: increased relative morbidity risk is associated with increased graft diameter

BACKGROUND

The purpose of this study is to compare the risk of peri-operative complication events associated with allogenic and autogenic grafts during routine follow-up for six months after primary arthroscopic anterior cruciate ligament (ACL) reconstruction surgery.

METHODS

A retrospective cohort study identified patients that underwent ACL reconstruction via an arthroscopically assisted single tunnel technique. Fixation was primarily cortical suspension (endobutton) from the femora and bicortical fixation (Washer-loc) in the tibia. Patients were monitored for six months following surgery. Morbidity was defined as complications during this period requiring medical or surgical intervention. Risk of complications was compared according to tissue type and patient characteristics. The Cochran-Mantel-Haenszel method was applied to estimate risk ratios (RR) and confidence intervals (CI) as the measure of association between graft type and morbidity risk.

RESULTS

The cohort included 413 eligible patients. Sixty six percent received allograft tissue, while the remainder received autograft tissue. Morbidity risk was 7.0% among patients receiving allograft tissue and 2.8% among patients receiving autograft tissue. Allograft demonstrated elevated risk of complication versus autograft (RR=2.3 (95% CI: 0.9-7.2)), though the data are of borderline significance (p=0.11). Complications were associated with larger graft diameter in comparison to patients who experienced no complication (9.0+/-1.2 mm v. 8.4+/-1.0mm, p=0.005).

CONCLUSION

The relative morbidity risk was about two-fold greater among patients receiving allograft tissue. Regardless of tissue type, graft size was larger among patients who experienced a complication.

LEVEL OF EVIDENCE

Level III.

Bone-patellar tendon-bone autograft versus allograft in outcomes of anterior cruciate ligament reconstruction: a meta-analysis of 5182 patients

BACKGROUND

Bone-patellar tendon-bone (BPTB) is a common autograft and allograft source used for anterior cruciate ligament (ACL) reconstruction. Although the failure rate is generally higher for allografts, donor site morbidity and anterior knee pain can be issues with BPTB autografts. Controversy exists regarding the functional outcomes, complications, and knee stability of these grafts, previous comparisons of which have been based on smaller samples of case series.

PURPOSE

To compare BPTB autografts to allografts for ACL reconstruction, specifically with regard to patient satisfaction, return to preinjury activity level, and postoperative functional outcomes.

STUDY DESIGN

Meta-analysis.

METHODS

A total of 76 studies published between 1998 and 2012, including a total of 5182 patients, were reviewed. It was not required for studies to be comparative in nature. Outcomes evaluated were graft rupture rate, return to preinjury activity level, overall and subjective International Knee Documentation Committee (IKDC), Lysholm, Tegner activity, Cincinnati Knee Rating System, pivot shift, and single-legged hop tests, as well as KT-1000 arthrometer side-to-side difference and presence of anterior knee pain. Summary odds ratios with 95% confidence intervals were calculated to compare BPTB autografts to allografts for each outcome.

RESULTS

Outcomes on subjective IKDC, Lysholm, Tegner, single-legged hop, and KT-1000 arthrometer were statistically significantly in favor of autografts. Return to preinjury activity level, overall IKDC, pivot shift, and anterior knee pain were significantly in favor of allografts, although allograft BPTB demonstrated a 3-fold increase in rerupture rates compared with autograft (12.7% vs 4.3%). There was no significant difference between the 2 groups for Cincinnati Knee scores.

CONCLUSION

Patients undergoing ACL reconstruction with BPTB autografts demonstrate lower rates of graft rupture, lower levels of knee laxity, and improved single-legged hop test results and are more generally satisfied postoperatively compared with patients undergoing reconstruction with allograft BPTB.

Incidence of postoperative anterior cruciate ligament reconstruction infections: graft choice makes a difference

BACKGROUND

Infections after anterior cruciate ligament reconstruction (ACLR) can be devastating. Hamstring tendon autografts may be more susceptible to infections than other graft types.

PURPOSE

To determine the incidence of surgical site infections (SSIs) in a large sample of patients who underwent ACLR and to evaluate the risk of superficial and deep SSIs associated with grafts used for ACLR.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

All primary ACLRs performed between February 2005 and September 2010 registered in the Kaiser Permanente ACLR registry were included in the study. The graft types evaluated included the bone-patellar tendon-bone (BPTB) autograft, hamstring tendon autograft, and allograft (all types). The main end point of the study, SSIs (deep and superficial), was prospectively ascertained using an electronic screening algorithm and adjudicated by the principal investigator. Descriptive statistics were used to describe the cohort, and logistic regression models were used to evaluate the likelihood of an infection.

RESULTS

There were 10,626 cases that fit the study criteria. The overall cohort was 64% male, mean age was 29 ± 11 years, and mean body mass index (BMI) was 27 ± 5 kg/m2. The overall incidence of SSIs was 0.48% (n = 51), with 17 (0.16%) superficial infections and 34 (0.32%) deep infections. Hamstring tendon autografts (n = 20; 0.61%) had the highest incidence of deep SSIs of the graft types (BPTB autograft, n = 2 [0.07%]; allograft, n = 12 [0.27%]; P < .001). After adjusting for age, sex, and BMI, the likelihood of a patient with a hamstring autograft having a deep SSI was 8.24 times higher (95% CI, 1.91-35.55; P = .005) than someone receiving a BPTB autograft. The risk of infections in allografts was not statistically significantly higher than BPTB autografts.

CONCLUSION

The overall SSI rate after ACLR was 0.48%. Deep SSIs were identified in 0.32% of the ACLR cases and superficial SSIs in 0.16%. An 8.2-times higher risk of SSIs was observed in hamstring tendon autografts compared with BPTB autografts. No difference in SSI incidence was identified between allografts and BPTB autografts. Surgeons should bear in mind that although the overall infection rates after ACLR are low, there is an increased risk of deep infections with hamstring tendon autografts.

Single-bundle anterior cruciate ligament reconstruction in active young men using bone-tendon achilles allograft versus free tendon achilles allograft

PURPOSE

The purpose was to prospectively compare the outcomes of anterior cruciate ligament (ACL) reconstruction using bone-tendon Achilles allograft with those of free tendon Achilles allograft in 2 groups of active young men.

METHODS

We enrolled 72 subjects in the study. Of these, 33 subjects who had ACL reconstruction with Achilles allograft with calcaneal bone block on its end (group I) and 34 who had ACL reconstruction with free tendon Achilles allograft (group II) were followed up for a minimum of 2 years. The Lachman test, pivot-shift test, and 1-leg hop test were evaluated at the last follow-up. The International Knee Documentation Committee classification, Lysholm score, and side-to-side difference were assessed preoperatively and at the last follow-up. The Tegner activity scale was evaluated before injury and at the last follow-up.

RESULTS

The mean follow-up period was 30.9 months (range, 26 to 38 months). At the last follow-up, there were no statistically significant differences between the 2 groups for the Lachman test, pivot-shift test, 1-leg hop test, International Knee Documentation Committee classification, Lysholm score, and side-to-side difference (P > .05). Three subjects in group I and three in group II showed an activity level 2 steps below the preinjury activity level. The rest of the subjects returned to the preinjury activity level or showed a level 1 step below the preinjury activity level.

CONCLUSIONS

There were no significant differences in clinical outcomes of ACL reconstructions using Achilles allograft between the bone-tendon group and the free tendon group in active young men. Free tendon Achilles allograft may be considered an option for ACL reconstruction.

LEVEL OF EVIDENCE

Level II, therapeutic study, randomized controlled trial.

Outcomes and revision rate after bone-patellar tendon-bone allograft versus autograft anterior cruciate ligament reconstruction in patients aged 18 years or younger with closed physes

PURPOSE

The purpose of this study was to compare revision rates and outcomes after anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone (BPTB) autografts versus BPTB allografts in patients aged 18 years or younger with closed physes.

METHODS

Institutional review board approval was obtained for this study. This study included 90 consecutive patients aged 18 years or younger with closed physes who underwent primary ACL reconstruction by a single surgeon between 1998 and 2009, with either BPTB autograft (n = 70) or BPTB allograft (n = 20). Patients who had concomitant ligament injuries were excluded. Outcome measures included the Lysholm score, Tegner activity scale, and patient satisfaction (0, very unsatisfied; 10, very satisfied). Failures were defined as cases requiring ACL revision surgery.

RESULTS

Of the 90 patients, 79 (88%) were contacted (20 of 20 with allografts and 59 of 70 with autografts). Of these 79 patients, 9 (11%) required revision ACL reconstruction. In the autograft group, 3% (2 of 59) required revision ACL reconstruction at a mean of 15.4 months (range, 13.0 to 17.7 months) after the index procedure. In the allograft group, 35% (7 of 20) required revision ACL reconstruction at a mean of 9.1 months (range, 5.3 to 12.0 months) after the index procedure. The allograft group was 15 (95% confidence interval [CI], 2 to 123) times more likely to require revision reconstruction than the autograft group (P = .001). The mean Lysholm score at follow-up was 85 (95% CI, 80.4 to 90.3) for the autograft group and 91 (95% CI, 88.1 to 97.3) for the allograft group (P = .46). The median Tegner activity scale was 7.0 (95% CI, 6.9 to 8.0) for autograft group and 6.5 (95% CI, 4.9 to 8.4) for the allograft group (P = .27). Median patient satisfaction score was 10 of 10 in both cohorts. No failures were seen in either group at 2 years postoperatively. Five of seven allograft failures occurred because of a premature return to sports.

CONCLUSIONS

No significant differences in function, activity, or satisfaction were found between allograft and autograft reconstructions in this patient population. The allograft group had a failure rate 15 times greater than that in the autograft group, with all failures occurring within the first year after reconstruction.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Anterior cruciate ligament graft choices

CONTEXT

Reconstruction of the anterior cruciate ligament (ACL) is a common surgical procedure; however, there is no consensus to what the best graft option is to replace the injured ACL. The main options available consist of allografts and autografts, which include patellar tendon, hamstring tendon, and quadriceps tendon autografts.

EVIDENCE ACQUISITION

The PubMed database was searched in August 2010 for English-language articles pertaining to ACL grafts.

RESULTS

Postoperative outcome variables were analyzed to determine similarities and differences among the different graft options. These variables include stability, strength, function, return to sports, patient satisfaction, complications, and cost.

CONCLUSIONS

Both allografts and the 3 main options for autografts can provide excellent results in ACL reconstruction and lead to a high percentage of satisfied patients. However, differences exist among the graft choices. Both the similarities and the differences are important to discuss with a patient who will be undergoing ACL reconstruction so that he or she has the best information available when making a choice of graft.