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All issues Volume 7 (2021) SICOT-J, 7 (2021) 16 Full HTML
Open Access
Issue
SICOT-J
Volume 7, 2021
Article Number 16
Number of page(s) 6
Section Knee
DOI https://doi.org/10.1051/sicotj/2021018
Published online 22 March 2021

© The Authors, published by EDP Sciences, 2021

Licence Creative CommonsThis is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Introduction

Most of the patients undergo reconstruction of the ACL based on destabilizing symptoms or the urge to participate in pivoting or cutting sports [1, 2]. While the gold standard for reconstruction has always been the bone-patellar tendon-bone (BPTB). The literature has reported figures as high as 30% of BPTB patients suffering from chronic anterior knee pain [3, 4]. This is why the quadrupled hamstring tendon option has become the mainstay practice in Kuwait for anterior ACLR [3, 4]. The reason being for this trend in Kuwaiti orthopedic surgical practice is that the cultural behaviors and daily living practices would be exacerbated by the BPTB related anterior knee pain should it happen [5–7].

However, one of the downfalls of using hamstring autografts as opposed to BPTB grafts is the success of the surgery relies on larger diameter grafts [8]. Major studies have suggested that the autograft hamstring diameter should ideally range between 7 and 10mm to avoid failure [9, 10]. And the current recommendations advocate for the use of hamstring autografts with a size of 8mm or above [11–13].

Although accurate preoperative autograft size prediction is difficult, clinical studies have shown that the diameter of the hamstring autograft correlates with patient height, gender, thigh circumference and BMI [13, 14].

The size of the hamstring tendon can be accurately determined by non-invasive methods such as magnetic resonance imaging(MRI) or ultrasound imaging [9–11]. The imaging modality of choice depends on what is available in medical centers. However, ultrasound has been proven to be more accurate in predicting the autograft size in the hands of an experienced operator than an MRI scan [9–11].

In terms of ACLR and risks of deep infections, BPTB grafts have significantly lower risks of deep infections followed by hamstring tendon grafts, leaving allografts with the highest infection risk [12].

The authors of this study initially hypothesized that the Kuwaiti population generally produces smaller four-strand hamstring autografts thus accounting for the need for higher revision rates [6]. The objective of this study was to investigate the population’s general anatomical size of their intra-operative hamstring autograft and ascertain whether or not the size of the autograft influenced our ACL revision rates. Our null hypothesis was that there would be no correlation between ACLR failure rate and diameter size. The current number of the Kuwaiti population was estimated to be around 5 million people, with the Kuwaitis accounting for 20% of that number [5, 6, 15]. This study was conducted in a tertiary center with the only ACLR facility in the country. Thus, all the ACLR in the country were performed by this unit.

Methods

The data was collected retrospectively from records held by the only ACLR unit in the country. The authors included the surgical records of patients who had isolated ACL injuries from the 1st January 2012 until the 31st of May 2018 with a minimum of 2-year follow-up required. Only patients who underwent the trans-portal anatomical reconstruction with hybrid fixation and suspensory fixation on the femur with an interference screw on the tibia [14] or the all-inside method using Arthrex® equipment were included [4, 16].

Patients who had their ACLR surgeries outside of Kuwait were excluded as well as patients with incomplete operative notes, missing files, and patients with lost follow-up records. Professional or contact athletes were also excluded. Three of the authors collected the relevant information from the patient’s operative and follow-up notes. The data collected from 3 separate data forms were then cross-referenced to identify any errors or conflicting information to assure for accuracy of the results. The patients were sorted into subgroups according to autograft size, number of strands, and need for augmentation. The patients in this study were categorized into three groups; less than 8mm, 8–9mm, and more than 9mm.

To investigate the relationship between primary ACLR autograft size and the number of strands used in the surgery, three statistical methods were used. First, ANOVA was applied to find out the between-group differences of mean graft size among different numbers of strands. Next, the graft sizes were categorized into different dummy variables as the outcome and categorized the number of strands as predictors. In such a way that the relative risk (RR) of graft failure of different graft sizes for a different number of strands could be calculated. To assess the relationship between revision rates and the initial autograft, a paired t-test was performed. Chi-square tests and Mann–Whitney-U tests were used to assess for age as a risk factor for revision surgery.

Results

Out of the 782 isolated ACLR cases, 71 (9.1%) of them had no record of their graft size. Out of the 711 patients included in this study, 11 patients had an ACLR revision (failure rate 2.1%), 9 of them were patients from the ≤8mm graft size group.

Figure 1 and Table 1, summarize the study population demographics. The mean graft size of the sample was 8.285mm (Table 2) and graft sizes≤8mm were used in 17.1% of all surgeries. The relationship between intraoperative graft size and the number of strands can be appreciated from Table 3, the median number of strands was 4 (53.0%).

thumbnail Figure 1

Histogram of Age and distribution plot of different age groups. Around 50% of all ACL patients were at the age between 21 and 30, while 30% of them were between 31 and 40years old.

Table 1

Descriptive analysis of age and final graft size.

Table 2

Percentages and Counts for different types of augmentation in different groups of graft size/strand.

Table 3

Number of strands, their frequency and percentage distribution, and the mean initial graft size for different strand configurations.

Table 4 shows that the quadrupled (4-strand) hamstring tendon autografts had the lowest size (8.056mm±0.63). The 4-strand hamstring tendon autograft size was significantly lower than the 5-strand (MD=−0.26±0.05, p<0.001), the 6-strand (MD=−0.56±0.14, p=0.001), the 7-strand (MD=−1.34±0.20, p<0.001), and the 8-strand (MD=−1.07±0.22, p<0.001) hamstring autografts.

Table 4

Post hoc test (Tukey HSD) – multiple comparisons of number of strands.

According to Figure 2, a 4-strand hamstring autograft size is 1.6 times more likely to be≤8mm (RR=1.613, 95% CI: 1.46, 1.75), and this relative risk decreases as for the graft sizes≤8.5mm and≤9mm. On the other hand, the relative risk of 5-strand hamstring autograft size to be≤8mm was significantly lower (RR=0.75, 95% CI: 0.61; 0.90, p=0.025). This relative risk increases for graft sizes≤8.5mm (RR=0.92, 95% CI: 0.83; 1.01, p=0.071) and≤9mm (RR=1.03, 95% CI: 0.99; 1.06, p=0.083). The initial graft size of patients who did not need any revision had a statistically and significantly greater impact compared with those who underwent the revision surgery (RR=7.2, 95% CI: 6.02; 8.35, p=0.007). Patients who had an initial autograft size of less than 8mm, were 7.2 times more likely to need revision surgery.

thumbnail Figure 2

Bar Plot illustrating the number of augmentations and the materials used. In addition, the percentage of each augmentation is written on top of the bars.

About 4.46% of all surgeries used some type of augmentation. The most common material used for augmentation was LARS® with 3.26%, while only 1.03% of all autografts were augmented with Nylon (Figure 3). There was an odds ratio of 0.27 (95% CI: 0.09; 0.85) with augmentation use is 4-strand autografts that were smaller than 8mm. However, there was no statistically significant difference observed among different graft size/strand categories (χ 2(8)=8.079, p=0.426).

thumbnail Figure 3

Relative risk (RR) of final graft sizes for different number of strands.

Discussion

ACLR failure is multifactorial, the current literature agrees that the diameter size of the autograft is a major contributor to ACLR failures. There have been general ranges recommended regarding the best size for the graft [13, 16, 17]. This study’s results show a clear correlation between the hamstring autograft size smaller than 8 and the risk of revision in our study cohort. From this study, we can significantly ascertain that 4-strand hamstring autografts of at least 8mm decreases the risk of revision rates.

The Authors understand that this study has several limitations due to scarce or unavailable data regarding the study population [18]. They did not measure the posterior tibial slope, activity level, insertion site as well as intercondylar notch of each patient. These are known contributors to ACL surgery failure rates [19]. The literature has reported that females suffer from ACL ruptures in females 2–4 times more than their male counterparts, however, our sample size only had 6 females in total so they were excluded from this study [4, 19]. The authors theorize that this could be due to cultural reasons that generally discourage females from pursuing athletic careers [4–6].

In Kuwait, only 42.6% of our sample size had delivered a 4-strand 8mm diameter hamstring autograft. About 40.2% of our patients needed more than 4 strands to achieve reach 8mm±augmentation. Meaning that achieving the desired 8mm can prove to be challenging [20–22]. However, this finding is in keeping with findings from other populations, mainly in North America [13, 17, 21]. When comparing our data with the largest cohort available on hamstring graft size in ACLR, the percentage of patients that had autografts with 4-strands sized≥8mm without augmentation was also around 37.9% [13, 17, 22–24]. Whereas in South India, a similar study to ours showed that≥8mm grafts can be produced using only 3-strands in 46% of their patients [25].

While considerable success in the restoration of knee stability has been demonstrated in ACLR, recent studies indicate that between 1.8 and 22% of primary grafts will still fail globally and require revision if they are less than 8mm in diameter [25–27]. Our population results fall into the lower end (2.1%) of these internationally reported rates of revision [28–30]. From the 17.1% of patients with autografts≤8mm in our study, about 7.2% needed a revision. In the MOON study, of the 62.1% of the patients with grafts≤8mm, 15.3% needed revision [13, 14, 17]. On the other hand, the South Indian cohort had 12% of their autografts less than≤7mm and only 12% of them needed a revision [31, 32]. Table 5, is a summary of the main findings of this study compared with the large-scale studies discussed.

Table 5

Comparison table of results found by large-scale studies.

Our study did not record a significant statistical difference between age and failure. However, the current evidence appearing in studies shows that revision is most common in the active and young population [33–37].

Conclusion

Although the causes for ACLR failure rates can be attributed to multiple confounding factors, this study concluded that there is a high association between the autograft diameter size and the need for revision surgery. The 4-strand hamstring autograft diameter of less than 8mm does correlate with an increased risk of ACLR failure rates. This study shows that patients who had an ACLR with a 4-strand autograft size of less than 8mm were 7.2 times more likely to require a revision.

Source of funding

The authors received no specific funding for this work.

Ethical approval

The Kuwaiti Ministry of Health Ethical Committee is the main authority of patient record keeping, and they had approved this study. Committee Reference Number: 2019/1069.

Conflicts of interest

The authors declare they have no conflicts of interest in relation to this article.

References

  1. Hewett TE, Schultz SJ, Griffin LY, Editors (2007) Understanding and preventing noncontact ACL injuries. Champaign, IL, Human Kinetics. [Google Scholar]
  2. Ahlden M, Samuelsson K, Sernert N, Forssblad M, Karlsson J, Kartus J (2012) The Swedish national anterior cruciate ligament register: A report on baseline variables and outcomes of surgery for almost 18,000 patients. Am J Sports Med 40, 2230–2235. [Google Scholar]
  3. Hamner DL, Brown CH Jr, Steiner ME, Hecker AT, Hayes WC (1999) Hamstring tendon grafts for reconstruction of the anterior cruciate ligament: Biomechanical evaluation of the use of multiple strands and tensioning techniques. J Bone Joint Surg Am 81, 549–557. [Google Scholar]
  4. Hamido F, Al Harran H, Al Misfer AR, El Khadrawe T, Morsy MG, Talaat A, Elias A, Nagi A (2015) Augmented short undersized hamstring tendon graft with LARS® artificial ligament versus four-strand hamstring tendon in anterior cruciate ligament reconstruction: Preliminary results. Orthop Traumatol Surg Res 101(5), 535–538. [PubMed] [Google Scholar]
  5. Hanna SS, AlKhalaf F, AlSamhan A, AlHamdan HA, AlAdwani BM, Khaja A (2020) Translation, adaptation and validation of the middle east lower limb score (MELLS) into Arabic. Int J Innov Res Med Sci 5(11), 488–492. [Google Scholar]
  6. Maqdes A, Hanna SS, Bouhamra AK, Khaja AF (2020) Cross-cultural adaptation and translation of the Constant Murley Score into Arabic. SICOT-J 6, 44. [EDP Sciences] [PubMed] [Google Scholar]
  7. Wilson TW, Zafuta MP, Zobitz M (1999) A biomechanical analysis of matched bone-patellar tendon-bone and double-looped semitendinosus and gracilis tendon grafts. Am J Sports Med 27, 202–207. [Google Scholar]
  8. Ma CB, Keifa E, Dunn W, Fu FH, Harner CD (2010) Can pre-operative measures predict quadruple hamstring graft diameter? Knee 17, 81–83. [CrossRef] [PubMed] [Google Scholar]
  9. Schwartzberg R, Burkhart B, Lariviere C (2008) Prediction of hamstring autograft diameter and length for anterior cruciate reconstruction. Am J Orthop 37, 157–159. [PubMed] [Google Scholar]
  10. Treme G, Diduch DR, Billante MJ, Miller MD, Hart JM (2008) Hamstring graft size prediction: A prospective clinical evaluation. Am J Sports Med 36, 2204–2209. [Google Scholar]
  11. Tuman JM, Diduch DR, Rubino LJ, Baumfeld JA, Nguyen HS, Hart JM (2007) Predictors for hamstring graft diameter in anterior cruciate ligament reconstruction. Am J Sports Med 35, 1945–1949. [Google Scholar]
  12. Bansal A, Lamplot JD, VandenBerg J, Brophy RH (2018 May) Meta-analysis of the risk of infections after anterior cruciate ligament reconstruction by graft type. Am J Sports Med 46(6), 1500–1508. [Google Scholar]
  13. Magnussen RA, Lawrence JT, West RL, Toth AP, Taylor DC, Garrett WE (2012) Graft size and patient age are predictors of early revision after anterior cruciate ligament reconstruction with hamstring autograft. Arthroscopy 28, 526–531. [PubMed] [Google Scholar]
  14. Mariscalco MW, Flanigan DC, Mitchell J, Pedroza AD, Jones MH, Andrish JT, Magnussen RA (2013) The influence of hamstring autograft size on patient- reported outcomes and risk of revision after anterior cruciate ligament reconstruction: A multicenter orthopaedic outcomes network (MOON) cohort study. Arthrosc J Arthrosc Relat Surg 29(12), 1948–1953. [CrossRef] [Google Scholar]
  15. Snaebjörnsson T, Hamrin Senorski E, Ayeni OR, et al. (2017) Graft diameter as a predictor for revision anterior cruciate ligament reconstruction and KOOS and EQ-5D values: A cohort study from the Swedish National Knee Ligament Register based on 2240 patients. Am J Sports Med 45(9), 2092–2097. [Google Scholar]
  16. Alhendi B, Al-Saifi S, Khaja A (2020) Medical tourism overseas: A challenge to Kuwait’s Healthcare System. Int J Travel Med Glob Health 8(1), 22–30. [Google Scholar]
  17. Kaeding CC, Aros B, Pedroza A, et al. (2011) Allograft versus autograft anterior cruciate ligament reconstruction: Predictors of failure from a MOON prospective longitudinal cohort. Sports Health 3, 73–81. [PubMed] [Google Scholar]
  18. Wright RW, Magnussen RA, Dunn WR, Spindler KP (2011) Ipsilateral graft and contralateral ACL rupture at five years or more following ACL reconstruction: A systematic review. J Bone Joint Surg Am 93, 1159–1165. [Google Scholar]
  19. Figueroa F, Figueroa D, Espregueira-Mendes J (2018) Hamstring autograft size importance in anterior cruciate ligament repair surgery. EFORT Open Rev 3(3), 93–97. [Google Scholar]
  20. Grassi A, Kim C, Marcheggiani Muccioli GM, Zaffagnini S, Amendola A (2017) What is the mid-term failure rate of revision ACL reconstruction? A systematic review Clin Orthop Relat Res® 475(10), 2484–2499. [Google Scholar]
  21. Goyal T, Paul S, Das L, Choudhury AK (2020) Correlation between anthropometric measurements and activity level on length and diameter of semitendinosus tendon autograft in knee ligament surgery: A prospective observational study. SICOT-J 6, 23. [EDP Sciences] [PubMed] [Google Scholar]
  22. Imam MA, Abdelkafy A, Dinah F, Adhikari A (2015) Does bone debris in anterior cruciate ligament reconstruction really matter? A cohort study of a protocol for bone debris debridement. SICOT J 1, 4. [EDP Sciences] [PubMed] [Google Scholar]
  23. Leo BM, Krill M, Barksdale L, Alvarez-Pinzon AM (2016) Failure rate and clinical outcomes of anterior cruciate ligament reconstruction using autograft hamstring versus a hybrid graft. Arthrosc J Arthrosc Relat Surg 32(11), 2357–2363. [Google Scholar]
  24. Sanders TL, Pareek A, Hewett TE, Levy BA, Dahm DL, Stuart MJ, Krych AJ (2016) Long-term rate of graft failure after ACL reconstruction: A geographic population cohort analysis. Knee Surg Sports Traumatol Arthrosc 25(1), 222–228. [PubMed] [Google Scholar]
  25. Shelbourne KD, Gray T, Haro M (2009) Incidence of subsequent injury to either knee within 5years after anterior cruciate ligament reconstruction with patellar tendon autograft. Am J Sports Med 37, 246–251. [Google Scholar]
  26. Barrett AM, Craft JA, Replogle WH, Hydrick JM, Barrett GR (2011) Anterior cruciate ligament graft failure: A comparison of graft type based on age and Tegner activity level. Am J Sports Med 39, 2194–2198. [Google Scholar]
  27. Challa S, Satyaprasad J (2013) Hamstring graft size and anthropometry in south Indian population. J Clin Orthop Trauma 4(3), 135–138. [Google Scholar]
  28. Borchers JR, Pedroza A, Kaeding C (2009) Activity level and graft type as risk factors for anterior cruciate ligament graft failure: A case-control study. Am J Sports Med 37, 2362–2367. [Google Scholar]
  29. Reinke EK, Spindler KP, Lorring D, et al. (2011) Hop tests correlate with IKDC and KOOS at minimum of 2years after primary ACL reconstruction. Knee Surg Sports Traumatol Arthrosc 19, 1806–1816. [PubMed] [Google Scholar]
  30. Lubowitz JH, Amhad CH, Anderson K (2011) All-inside anterior cruciate ligament graft-link technique: Second-generation, no-incision anterior cruciate ligament reconstruction. Arthrosc J Arthrosc Relat Surg 27(5), 717–727. [Google Scholar]
  31. Owusu-Akyaw KA, Kim SY, Spritzer CE, Collins AT, Englander ZA, Utturkar GM, Garrett WE, DeFrate LE (2018) Determination of the position of the knee at the time of an anterior cruciate ligament rupture for male versus female patients by an analysis of bone bruises. Am J Sports Med 46(7), 1559–1565. [Google Scholar]
  32. Napier RJ, Garcia E, Devitt BM, Feller JA, Webster KE (2019) Increased radiographic posterior tibial slope is associated with subsequent injury following revision anterior cruciate ligament reconstruction. Orthop J Sports Med 7(11). [Google Scholar]
  33. Andernord D, Desai N, Bjornsson H, Gillen S, Karlsson J, Samuelsson K (2015) Predictors of contralateral anterior cruciate ligament reconstruction: A cohort study of 9061 patients with 5-year follow-up. Am J Sports Med 43(2), 295–302. [Google Scholar]
  34. Andernord D, Desai N, Bjornsson H, Ylander M, Karlsson J, Samuelsson K (2015) Patient predictors of early revision surgery after anterior cruciate ligament reconstruction: A cohort study of 16,930 patients with 2-year follow-up. Am J Sports Med 43(1), 121–127. [Google Scholar]
  35. Kopf S, Pombo M, Szczodry M, Irrgang J, Fu F (2011) Size variability of the human anterior cruciate ligament insertion sites. Am J Sports Med 39(1), 108–113. [Google Scholar]
  36. Guenther D, Irarrázaval S, Albers M, Vernacchia C, Irrgang JJ, Musahl V, Fu FH (2017) Area of the tibial insertion site of the anterior cruciate ligament as a predictor for graft size. Knee Surg Sports Traumatol Arthrosc 25, 1576–1582. [PubMed] [Google Scholar]
  37. Dhanakodi N, Thilak J, Varghese J, Menon KV, Varma HK, Tripathy SK (2019) Ceramic bone graft substitutes do not reduce donor-site morbidity in ACL reconstruction surgeries: A pilot study. SICOT-J 5, 14. [EDP Sciences] [PubMed] [Google Scholar]

Cite this article as: Alkhalaf FNA, Hanna S, Alkhaldi M, Alenezi F & Khaja A (2021) Autograft diameter in ACL reconstruction: size does matter. SICOT-J 7, 16

All Tables

Table 1

Descriptive analysis of age and final graft size.

In the text
Table 2

Percentages and Counts for different types of augmentation in different groups of graft size/strand.

In the text
Table 3

Number of strands, their frequency and percentage distribution, and the mean initial graft size for different strand configurations.

In the text
Table 4

Post hoc test (Tukey HSD) – multiple comparisons of number of strands.

In the text
Table 5

Comparison table of results found by large-scale studies.

In the text

All Figures

thumbnail Figure 1

Histogram of Age and distribution plot of different age groups. Around 50% of all ACL patients were at the age between 21 and 30, while 30% of them were between 31 and 40years old.
In the text
thumbnail Figure 2

Bar Plot illustrating the number of augmentations and the materials used. In addition, the percentage of each augmentation is written on top of the bars.
In the text
thumbnail Figure 3

Relative risk (RR) of final graft sizes for different number of strands.
In the text

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