Editorial Commentary: How to Increase Hamstring Tendon Graft Size for Anterior Cruciate Ligament Reconstruction

The concept of a five-strand hamstring tendon autograft for anterior cruciate ligament reconstruction is not new. The concept of a five-strand hamstring tendon autograft was largely ignored until recent studies showed higher failure and revision rates for hamstring ACL reconstructions performed with graft diameters less than 8 mm. In the majority of patients in the United Arab Emirates, four-strand hamstring tendon autografts result in a graft diameter between 6.5-7.5 mm. As a result, since 2006, I have completely abandoned using four-strand hamstring tendon autografts in favor of five-and six-stranded hamstring tendon autografts for ACL reconstructions. The key to performing five-or six-strand hamstring tendon autografts lies in the ability to triple the semitendinosus tendon and in the case of six-strand hamstring tendon grafts, the gracilis tendon. Although, five-and six-strand hamstring tendon autografts can increase the diameter of hamstring tendon ACL grafts, the question of whether these grafts will reduce failure and revision rates remains unanswered.     

Editorial Commentary: Goldilocks and the Three Grafts: Managing Tendon Harvest and Graft Length Problems in Autograft Anterior Cruciate Ligament Reconstruction

Autograft hamstring tendon harvest in anterior cruciate ligament (ACL) reconstruction can occasionally result in a graft length that is inadequate for creation of a robust ACL graft. Patients at risk for an abnormally short hamstring may also be high risk for ACL reinjury. Graft augmentation with allograft may be a suboptimal solution to this problem. Therefore, a reliable means for preoperative estimation of hamstring tendon length by magnetic resonance imaging measurement could avoid this pitfall. However, even with a reliable correlation between magnetic resonance imaging measurement and actual harvested tendon length, establishing a simple, clinically relevant threshold below which hamstring grafts should be avoided remains elusive. By contrast, all-soft-tissue quadriceps autograft avoids the potential length problems inherent to both bone tendon bone (graft–tunnel mismatch) and hamstring tendon grafts, but intermediate- and long-term outcome studies are still needed to validate all-soft-tissue quadriceps autograft in ACL reconstruction.     

Relationship between anthropometric measurements and hamstring autograft diameter in anterior cruciate ligament reconstruction

The role of anthropometric measurements in the prediction of hamstring autograft size remains unclear. In this internal review board - approved study, we evaluated medical records for patients receiving anterior cruciate ligament (ACL) reconstruction with hamstring autograft at our institution between 2006 and 2008. One hundred and thirty-two patients received hamstring autografts. Correlation coefficients and step-wise multiple linear regression analysis were used to determine the relationships between sex, age, height, body mass index (BMI), and hamstring graft diameter. Women had significantly smaller grafts than men (P < .00001). Twenty-four patients had grafts less than 7 mm in diameter and 18 of those patients were female. Age and BMI did not correlate with graft diameter in women. Height correlated to graft diameter in women (P = .002, R(2) = 0.14). Women shorter than 65 in had significantly smaller graft diameters (mean [SD], 6.94 [0.45] mm), than those women 65 in and taller (mean [SD], 7.20 0.49] mm; (P = .03). Age and height did not correlate with graft size in men. BMI greater than 25 kg/m(2) correlated with larger graft diameter, but BMI less than 18 kg/m(2) did not predict graft sizes less than 7 mm. Therefore, alternative graft options should be considered in women less than 65 in tall.     

Editorial Commentary: With Appropriate Anterior Cruciate Ligament Graft Selection,All-Inside Reconstruction Results in Excellent Outcomes: Stay “Inside” and Be Cognizant of Hamstring Graft Diameter Expectations in Shorter Patients

All-inside anterior cruciate ligament (ACL) reconstruction is a minimally invasive and anatomic technique with predictably excellent results. The array of graft choices that exists for skilled arthroscopists include semitendinosis autograft with or without gracilis, quadriceps tendon autograft, and patellar tendon autograft and allograft. The advantages of all-inside ACL reconstruction include independent femoral socket creation and less pain compared with a full tibial tunnel in the early postoperative period. This is a technique that should not trump appropriate graft selection. It is expected that autografts will fare better in younger patients who participate in activities at greater risk for ACL injuries. Selection of a semitendinosis autograft results in predictably excellent results when graft diameters are 8 mm or greater. Quadrupling the semitendinosis and adding the gracilis when needed can provide sufficient graft diameter in many patients. However, caution should be taken when harvesting hamstring grafts from shorter patients. Semitendinosis tendons in such patients are sometimes not long enough to quadruple and can result in a diameters less than 8 mm even when the gracilis is added. With appropriate graft selection, staying “inside” for ACL reconstruction is expected to result in great objective and subjective outcomes for our patients.     

关节镜下保留残端五重折股薄肌腱重建前交叉韧带的疗效分析

目的 介绍一种单独应用股薄肌腱重建前交叉韧带(ACL)的方法,并评估其疗效.方法 2003年4月至2008年5月,前瞻性研究采用保留ACL胫骨侧残留部分单独应用股薄肌腱重建ACL的方法治疗40例ACL损伤患者,其中男22例,女18例;年龄17～43岁,平均30.7岁.急性损伤33例,陈旧性损伤7例.受伤至手术时间平均3.4周(1～12周).术中评价所取股簿肌腱的长度,移植腱的长度及直径.术后评价包括KT-2000的前方不稳定性患健差,膝关节活动度,屈膝肌力的患健差,手术前后的IKDC评分及VAS评分.结果 所取股薄肌腱的长度平均为239 mm;移植腱直径为7.6 mm,长度为41.4 mm.KT-2000的前方不稳定性患健差术前平均为5 mm,术后平均为1 mm,差异有统计学意义(P＜0.05).膝关节活动度与健侧最大相差不到5°,差异无统计学意义(P＞0.05).术后6个月患膝在60°/s伸膝时扭矩恢复到健侧的89%,术后1年恢复到92%,术后2年恢复剑95%;术后6个月患膝在90°/s屈膝时扭矩恢复到健侧的85%,术后1年恢复到86%,术后2年恢复到89%.术前IKDC评分平均为49.3分,术后2年平均为95.0分;VAS评分术前平均为30.3分,术后2年平均为85.4分,差异均有统计学意义(P＜0.05).结论 单独廊用股薄肌腱重建ACL,屈膝肌力恢复满意.保留残留韧带可促进重建韧带的血运和本体感觉的恢复,加速患者的康复.     

All-Inside Anterior Cruciate Ligament Reconstruction

Anterior cruciate ligament (ACL) reconstruction is one of the most commonly performed knee operations. An “all-inside” technique creates bone sockets for ACL graft passage, as opposed to more traditional full bone tunnels, and typically incorporates suspensory fixation instead of screw fixation to secure the graft. This technique may be indicated for any ACL reconstruction surgery, where adequate bone stock exists to drill sockets and to use cortical fixation. The technique may be used with all soft tissue, as well as bone plug ACL grafts and autograft hamstring or quadriceps tendon; most allograft tendon options may be performed with an all-inside technique. Advantages include anatomic tunnel/socket placement, decreased postoperative pain and swelling, minimal hardware, appropriate graft tensioning and retensioning, and circumferential graft to bone healing. Tips for successful all-inside surgery include matching graft diameter to socket diameter, drilling appropriate length sockets based on individual graft length, so as not to “bottom out” the graft and confirming cortical button fixation intraoperatively. Potential complications include graft-socket mismatch, full-tunnel reaming, and loss of cortical fixation. Multiple studies have shown the all-inside technique to have similar or superior biomechanical properties and clinical outcomes compared to the more traditional full-tunnel ACL reconstruction techniques.     

Arthroscopic anterior cruciate ligament reconstruction with quadriceps tendon-patellar bone autograft

BACKGROUND: Surgical reconstruction of the anterior cruciate ligament (ACL) is indicated in the ACL-deficient knee with symptomatic instability and multiple ligaments injuries. Bone patellar tendon-bone and the hamstring tendon generally have been used. In the present study, we describe an alternative graft, the quadriceps tendon-patellar bone autograft, by using arthroscopic ACL reconstruction. METHODS: From March of 1996 through March of 1997, a quadriceps tendon-patellar bone autograft was used in 12 patients with ACL injuries. RESULTS: After 15 to 24 months of follow-up, the clinical outcome for those patients with this graft have been encouraging. Ten patients could return to the same or a higher level of preinjury sports activity. According to the International Knee Documentation Committee rating system, 10 of the 12 patients had normal or nearly normal ratings. Recovery of quadriceps muscle strength to 80% of the normal knee was achieved in 11 patients in 1 year. CONCLUSION: The advantages of the quadriceps tendon graft include the following: the graft is larger and stronger than the patellar tendon; morbidity of harvest technique and donor site is less than that of patellar tendon graft; there is little quadriceps inhibition after quadriceps harvest; there is quicker return to sports activities with aggressive rehabilitation. A quadriceps tendon-patellar autograft is a reasonable alternative to ACL reconstruction in patients who are not suitable for either a bone-patellar tendon-bone autograft or a hamstring tendon autograft.     

Small Size Autograft versus Large Size Allograft in Anterior Cruciate Ligament Reconstruction

BackgroundA small autograft diameter negatively affects functional outcomes, knee stability, and the risk of rerupture after anterior cruciate ligament (ACL) reconstruction, whereas the strength of allograft decreases over time. Therefore, it is not clear whether the use of smaller autografts or the use of larger allografts in ACL yields better results. The aim of this study was to compare the outcome of smaller autografts and larger allografts for ACL reconstruction.MethodsFifty-one patients who underwent ACL reconstruction with hamstring tendon autografts (size ≤ 8 mm) and 21 patients who underwent ACL reconstruction with allografts (size ≥ 10 mm) were included in our study. All patients underwent the same aggressive early postoperative rehabilitation program. There were no significant differences between the autograft and allograft groups regarding the preoperative patient age, sex, time from injury to surgery, and average follow-up time.ResultsThe mean diameter of the 4-stranded hamstring tendon grafts used as autografts was 7.48 ± 0.33 mm and the mean diameter of the allografts was 10.76 ± 0.67 mm. According to specific tests for the ACL (anterior drawer, Lachman, and pivot shift) and clinical evaluation tests (Lysholm knee scoring scale and International Knee Documentation Committee questionnaire), the final follow-up results were significantly better than the preoperative status in both autograft and allograft ACL reconstruction groups. Therefore, there were no significant differences between the autograft and allograft groups preoperatively and at the final follow-up.ConclusionsThe large size of the graft in ACL reconstruction has been reported to affect results positively. However, in our study, we could not find any significant differences between the smaller size autografts and larger size allografts in terms of inadequacy, rerupture, and final follow-up functional results. Although allografts were significantly larger than autografts, we did not have the positive effect of larger size grafts. Smaller size autografts were as effective as the larger size allografts.     

Chronic anterior cruciate ligament insufficiency results in inferior quality hamstring autografts

Background

Availability of a good quality autograft of adequate length is the first step towards a successful knee ligament reconstruction. Being able to predict the quality and length of hamstring autograft can go a long way in making the surgeon’s pre-operative planning a lot easier. The purpose of this study was to find out if any correlation existed between the duration of ACL injury with history of repeated instability episodes and the quality and length of Hamstring graft that was harvested.

Methods

Forty consecutive patients who underwent ACL reconstruction using quadrupled Hamstring tendon graft were evaluated with regard to the duration of injury, number of instability episodes and graft characteristics like difficulty in harvesting the graft, quality and length of the graft.

Results

We found a statistically significant difference between the usable length of harvested Hamstring tendon in patients with acute and chronic injury (p = 0.004). There was a significantly high risk of the graft being shorter and of poor quality in patients with chronic injury (odds ratio = 5.7).

Conclusion

Chronicity of ACL injury with repeated strains can cause fibrosis at the musculotendinous junction and result in harvest of a poor quality and short hamstring autograft. A detailed history with regard to duration of injury and repeated instability episodes will help a surgeon plan better when anticipating a sub-optimal graft.

     

Clinical outcomes after ACL reconstruction with free quadriceps tendon autograft versus hamstring tendons autograft. A retrospective study with a minimal follow-up two years

ObjectiveThe aim of this retrospective study was to compare the clinical outcomes of anatomic single bundle ACL reconstruction using either a free quadriceps tendon autograft or a quadrupled hamstring autograft with a minimum follow-up of 24 months.MethodsConsecutive patients undergoing ACL reconstruction using either a free quadriceps tendon autograft or hamstring tendon autograft from January 2013 to December 2014 were included. ACL reconstruction was done in all patients due to isolated ACL tears. Patients with associated cartilage lesions > Outerbridge III, meniscal lesions in need of meniscectomy or repair as well as patients with prior knee surgery on the affected or contralateral knee were excluded. The primary outcome evaluation was the side-to-side difference in instrumented Lachman testing. Secondary outcome evaluation consisted in the Lysholm, modified Cincinnati and SF-36 scores. Side-to-side difference in range of motion and thigh diameter was also documented.ResultsAfter applying the inclusion/exclusion criteria, a total of 82 patients were identified and 72 (87.8%) presented to the hospital for follow-up. There were 39 patients with quadriceps graft (30.64 ± 8.71, range: 18–53 years) and 33 patients with hamstrings (28.60 ± 6.74, range: 18–46 years). No statistically significant difference between groups was detected with regard to KT-1000 measurements (p = 0.326). No significant difference was found between the mean postoperative Lysholm (p = 0.299), the modified Cincinnati (p = 0.665) and the general SF-36 scores between groups (p = 0.588). Less side-to-side thigh diameter difference was noted in the quadriceps graft group (p = 0.026).ConclusionIn conclusion, similar clinical results, in terms of stability and subjective measures, can be obtained after ACL reconstruction both with a free quadriceps and a 4-strand hamstring tendons autograft.Level of evidenceLevel III, Therapeutic Study.     

Hamstring autograft utilization in reconstructing anterior cruciate ligament: Review of harvesting techniques,graft preparation,and different fixation methods

Rupture of the anterior cruciate ligament (ACL) is a common orthopedic injury. Various graft options are available for the reconstruction of ruptured ACL. Using the hamstring muscle as an autograft was first described in 1934, and it remains a commonly harvested graft for ACL reconstruction. Hamstring autografts can be harvested using the traditional anteromedial approach or the newer posteromedial technique. An isolated semitendinosus tendon can be used or combined with the gracilis tendon. There are numerous methods for graft fixation, such as intra-tunnel or extra-tunnel fixation. This comprehensive review discusses the different hamstring muscle harvesting techniques and graft preparation options and fixation methods. It provides a comprehensive overview for choosing the optimal surgical technique when treating patients.     

Reconstruction of the anterior cruciate ligament in females

Purpose: To compare the clinical results of anterior cruciate ligament reconstruction in female patients using quadruple-looped hamstring autograft versus patellar tendon autograft at minimum 2-year follow-up. Type of Study: Case series. Methods: A prospective clinical review was performed to compare the results of ACL reconstruction with hamstring versus patellar tendon autograft in a group of female patients. Exclusion criteria included chronic injuries (greater than 3 months), associated collateral ligament injuries, Workers’ Compensation or litigation cases, and bilateral anterior cruciate ligament injuries. There were 39 female patients in the hamstring group (average follow-up, 40.9 months) and 37 female patients in the patellar tendon group (average follow-up, 52 months). Both types of grafts were fixed with an EndoButton proximally and with sutures tied over a post or button distally. The postoperative rehabilitation regimen was identical for both groups. Objective parameters evaluated included preinjury and postoperative Tegner and Lysholm scores, side-to-side KT-1000 maximum-manual arthrometer differences, and clinical examination including Lachman and pivot-shift tests. Graft failure was defined by any one of the following: a KT-1000 difference of greater than 5 mm, a 2+ Lachman, a 1+ or greater pivot shift, or revision surgery. Results: The failure rate in the hamstring group was 23% versus 8% in the patellar tendon group, which was not statistically significant (P > .1). Comparison of preinjury Tegner activity scores to postoperative scores revealed that patients in the hamstring group did not return to their preinjury level of activity (preinjury 6.54 v postoperative 5.17) as well as patients in the patellar tendon group (preinjury 6.20 v postoperative 6.59). Patients in the hamstring group had a significant increase in pain compared with the patellar tendon group (P = .034). Conclusions: Although not statistically significant, the hamstring group had more failures, more laxity on clinical examination, and more patients with larger KT-1000 arthrometer differences. These results indicate a trend toward increased graft laxity in female patients undergoing reconstruction with hamstring autograft compared with patellar tendon when evaluated by a single surgeon using similar fixation techniques at short- to medium-range follow-up. More studies with larger patient numbers using current fixation techniques are necessary to confirm these findings.     

Semitendinosus muscle fatty infiltration following tendon harvest in rabbits

The hamstring tendon autograft is one of the most commonly used graft choices in Anterior cruciate ligament (ACL) reconstruction. There are conflicting results regarding postoperative hamstring strength deficits in patients who have had a hamstring graft. The semitendinosus tendon has been shown to regenerate after harvesting for ACL autograft, suggesting that the muscle has the potential to regain normal function. However, no studies have been performed to define the microstructural changes that occur in the semitendinosus muscle after tendon resection. In this study, we hypothesized that fatty infiltration of the semitendinosus muscle after tendon harvest in New Zealand White rabbits increases postoperatively and remains constant or increases during the first year of repair. The semitendinosus tendon was unilaterally detached and harvested from 15 rabbits. Five rabbits were sacrificed at 3‐, 6‐, and 12‐month intervals, and the semitendinosus muscle‐tendon units were analyzed. The contralateral unoperated limb served as the control. The gross tendon and muscle dimensions and histologic percentage of fatty infiltration were measured. We found no significant difference in fatty infiltration at any time point between the control muscle and test specimens and that there was no progression of fatty infiltration over time. If these results hold true in humans, natural repair of the hamstring muscle following tendon harvest during ACL autograft reconstruction is not inhibited by fatty infiltration. © 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1234–1239, 2013     

Hamstring graft size and anthropometry in south Indian population

Background and AimThe role of anthropometric measurements in the prediction of hamstring autograft size in Indian population remains unclear. Till now, no studies have been done on Indian population.MethodsWe evaluated 41 consecutive patients (34 males, 7 females) prospectively with anterior cruciate ligament deficiency scheduled for reconstruction using hamstring autograft at our institution between June 2011 and June 2013. Preoperatively we recorded age, gender, height, weight, body mass index, and activity level. Intraoperative measurements of semitendinosus tendon like absolute length, diameter before fashioning the graft and final diameter of the tripled graft using sizing tubes calibrated to 1 mm. Correlation coefficient (Pearson's r) analysis was used.ResultsAs per study there is no correlation between graft diameter, age, sex, weight, activity, and body mass index, of patients. Height of patients correlated to graft diameter in both Indian men and women (p < 0.001).ConclusionAnthropometric measurements such as weight, gender, activity level cannot be used as definitive predictors for the hamstring graft diameter during harvest but height of the patients can be taken as good predictor in Indian population.     

Quadriceps Tendon Graft for Anterior Cruciate Ligament Reconstruction: THE GRAFT OF THE FUTURE!

Anterior cruciate ligament (ACL) reconstruction is one of the most common orthopaedic surgeries performed on active people in the world. One of the most important surgical decisions is graft type for use in the reconstruction. Despite extensive research on optimal graft choice for ACL reconstruction, discrepancy exists among practicing surgeons' graft preference. Recently, the quadriceps tendon has gained popularity for use as a graft source for ACL reconstruction.The all soft tissue quadriceps graft offers many advantages over other autograft choices. Histologically it has 20% more collagen fibrils per cross-sectional area than the patellar tendon (PT). Biomechanically, its ultimate load is 70% > than that of a similar width PT graft, while its modulus is more similar to the native ACL than either the PT or hamstring graft. Anatomically the quadriceps tendon has significantly more volume than the PT. Thus, even after harvest of the quadriceps graft, the remaining quadriceps tendon is still 80% stronger than the intact PT!The length and cross-sectional area of the quadriceps tendon graft can be tailored to the needs of the patient. On any patient over 5 feet tall, a graft length of 7 cm can be obtained. Because the thickness of the tendon is almost twice the thickness of the same patient's PT, a graft diameter from 7 to 11 mm can easily be achieved. Thus, this graft can be customized for both primary and revision surgeries.Harvest site morbidity is minimal. An incision less than 2 cm in an area with no significant cutaneous nerves without harvest of any patella bone leads to no significant harvest site pain, numbness, or palpable defect.Clinical outcomes using this graft are excellent. Our prospective data on nearly 1,000 grafts, with a mean patient age of 20 years old, show a 4.2% failure rate. Thus, the all soft tissue quadriceps graft will be the surgical choice for ACL reconstruction for future athletes.     

Hamstring tendon autograft better than bone patellar-tendon bone autograft in ACL reconstruction: a cumulative meta-analysis and clinically relevant sensitivity analysis applied to a previously published analysis

Background Current debate on treatment options for anterior cruciate ligament (ACL) reconstruction complicate the choice between hamstring and bone patellartendon bone autografts. We hypothesized a priori that cumulative meta-analysis (a form of sensitivity analysis) might show that the evidence for reduction of morbidity by hamstring grafts could have been reached at an earlier time. Furthermore, we hypothesized a priori that modern state-of-the-art hamstring graft fixation technique would give similar results regarding stability as bone-patellar tendon-bone autografts.

Methods We performed a cumulative meta-analysis and sensitivity analysis based on femoral graft fixation techniques to compare hamstring autograft and bonepatellar tendon-bone autografts in ACL reconstruction derived from a previously published meta-analysis.

Results Cumulatively, that hamstring autograft reduces anterior knee pain had already reached statistical significance in 2001 (relative risk 0.49 (95%CI: 0.32-0.76; p = 0.001, I2 = 0%)). The modern endobutton hamstring graft fixation technique (2 studies) yielded similar stability in the Lachman test as bone-patellar tendon-bone grafts, with a relative risk of 1.1 (95%CI: 0.82-1.5; p = 0.6, I2 = 0%). Exclusion of the endobutton group explains the increased laxity in the hamstring graft group.

Interpretation Cumulative meta-analysis strengthens the evidence for reduced morbidity using hamstring tendon autograft for anterior cruciate ligament reconstruction. Sensitivity analysis focusing on state-of-the-art hamstring graft fixation techniques further weakens the evidence that bone-patellar tendon-bone autografts provide better stability.     

Joint Infection Unique to Hamstring Tendon Harvester Used During Anterior Cruciate Ligament Reconstruction Surgery

Joint infection after anterior cruciate ligament (ACL) reconstruction is a rare but important clinical issue that must be resolved quickly to prevent secondary joint damage and preserve the graft. After careful analysis, we observed 3 infection cases within a 12-month period after ACL reconstruction, which represented an abnormally elevated risk. All reconstructions were performed by the same surgeon and used hamstring tendon allograft. For each surgery, the Target Tendon Harvester (DePuy Mitek, Raynham, MA) was used to harvest hamstring tendons. Through our review, we learned that this instrument was sterilized while assembled. It is our belief that ineffective sterilization of this hamstring graft harvester served as the origin for these infections. We have determined that appropriate sterilization technique involves disassembly of this particular hamstring tendon harvester before sterilization because of the tube-within-a-tube configuration. We have since continued to use the Target Tendon Harvester, disassembling it before sterilization. There have been no infections in the ensuing 12 months during which the surgeon performed over 40 primary ACL reconstructions via hamstring autograft. The information from this report is intended to provide arthroscopists with information about potential sources of infection after ACL reconstruction surgery.     

腘绳肌腱结合双固定技术重建前交叉韧带

目的探讨采用腘绳肌腱股骨端胫骨端双固定技术重建前交叉韧带(ACL)的可行性及近期疗效。方法对25例ACL损伤行关节镜下ACL重建术,采用笔者自行设计双监视法解剖等长重建技术建立股骨胫骨隧道。移植物股骨端用Endobutton钢板和Rigidfix固定,胫骨端用Bio-Intrafix和Stample门形加压钉固定。结果本组获随访12～18(13.76±1.61)个月,未发现滑膜炎、韧带断裂、活动度明显障碍等并发症。根据Lysholm膝关节功能评分,术前评分:20～48(31.32±8.71)分;术后1年评分:90～98(94.96±2.56)分(t=37.69,P<0.01)。结论在腘绳肌腱重建ACL中应用股骨端胫骨端双固定技术具有手术操作简便,固定牢固,效果可靠的优点,值得推广。     

ACL reconstruction by patellar tendon

In 50 knees the length of the anterior cruciate ligament (ACL), the patellar tendon, and the distance between the tibial tuberosity and the femoral origin of the ACL were evaluated by means of three-dimensional magnetic resonance imaging (MRI), which permits subsequent reconstruction of any sectional view. The measurements showed that the patellar tendon was always markedly longer than the ACL (mean 14.4 mm), but always shorter than the distance between the tibial tuberosity and the femoral insertion of the ACL (mean 19.2 mm). The mean lengths of the ACL and the patellar tendon were 38.2 mm and 52.6 mm, respectively. The mean distance between the femoral ACL origin and the tibial insertion of the patellar tendon was 71.8 mm. These results demonstrate that a distally based patellar tendon autograft alone (with the patellar bone block but without extension into the periosteum of the patella or the quadriceps tendon) cannot be placed anatomically correctly to the isometric femoral insertion of the ACL. When the patellar tendon is used for ACL reconstruction, it must be implanted as a free autograft. Nevertheless, considerable variations of length must be taken into account.     

Editorial Commentary: Addition of the Sartorius Tendon to Small-Diameter Hamstring Anterior Cruciate Ligament Autografts May Improve Outcomes in Pediatric and Revision Cases

Graft selection in anterior cruciate ligament reconstruction can have a pivotal role in a successful outcome. One of the major concerns with hamstring autograft is the variability of the diameter of each tendon, and grafts with a diameter of less than 8 mm may result in an increased failure rate. The addition of the sartorius tendon as a fifth strand in small-diameter hamstring autografts increases graft strength and diameter. This may improve outcomes in pediatric and revision cases.