Choosing the optimal graft for ACL reconstruction is remaining a controversial topic, attributed to the various factors that confound to obtain the proper decision such as patient’s age, sports activities, surgeon preference, and nature of the occupation. The most common used autografts that surgeons preferred to use for their patients are hamstring tendon (HS) or bone–patellar tendon-bone (BPTB) autografts reconstruct the ACL [10] The current evidence with the available literature is still debated regarding the optimal option without the agreement of the superiority of a particular graft. Some literature recommended the use of BPTB autograft for the advantages of healing and increase stability (assessed through KT-1000 arthrometer testing), negative pivot shift, and decreased risk for revision [11, 12 [. Nevertheless, there are recent literature published that recommend HS autograft due to the advantages of increased extension strength, decrease the incidence of anterior knee pain, and minimal donor site morbidity] 13, 14[. Another published studies support the use of hamstring autograft for those patients that cannot tolerate anterior knee pain as they need to kneel in various daily living activities and elucidate the possibility of having a higher risk to develop long term anterior knee pain with BPTB autograft compared with HS [4, 8, 15, 16]. Some studies suggested the injury or neuroma of the infrapatellar branch of the saphenous nerve is suggested to be the cause of this knee pain [32]. A 2-incision approach was used for patellar tendon harvest, which has been shown previously to decrease the kneeling pain [32]. Moreover, patients who are treated with BPTB had increased pain in the acute postoperative period when compared with those treated with HS [30].
A meta-analysis of 22 studies with a total of 1930 patients undergoing ACL reconstruction conducted by Xie et al., reported that patients treated with BPTB autograft had more significant long-term kneeling pain and anterior knee pain when compared with those treated with HS autografts [17]. Furthermore, Li et al. evaluated outcomes of ACL reconstruction among nine randomized controlled trials for 738 patients and found that BPTB autografts produced significant anterior knee and kneeling pain. ]18[
Therefore, we aimed in our study to investigate the long-term outcomes of BPTB autograft versus HS autograft for which producing a better impact on patient’s activities. Interestingly, our study conducted among sample of muslim patients whom need kneeling as a major activity to perform prayers which should assist the surgeon to select the proper autograft of superior outcomes for the injuried patients. which might contribute to assist the surgeon in selecting the autograft with superior outcomes in the region. Hereby, the purpose of our study was obtained by the international knee documentation committee (IKDC) subjective knee evaluation form, which is one of the reliable instruments used commonly to determine results following various knee procedures, including ACL reconstructions. Thus, it is valid to measure knee symptoms as well. [19]
This measurement tool was used as a primary method for the collected sample to measure subjective satisfaction and kneeling pain postoperatively. We found interestingly in our result that insignificant differences between groups when comparing patient-reported outcome measures, with mean IKDC scores of 68.5 and 62.55 in the BPTB and HS groups, respectively. According to IKDC item 9c, ten patients in the BPTB group versus 18 in the HS group experienced mild pain during kneeling, which is reasonable. Overall postoperative results are satisfactory within each group in terms of IKDC subjective scores, activities of daily living when compared to pre‑operative scores. Similar findings reported by Eriksson et al. which were consistent with majority of patients in the group 80% scored normal and minimal pain while 20% of patients scored abnormal IKDC grades [20]. Outcomes of our study demonstrates that both types of reconstruction are effective methods of restoring knee stability and producing satisfactory outcomes in means of post-operative anterior knee pain and kneel pain. There was insignificant statistical difference in the IKDC score between two groups after 1-year of follow-up [21].
To minimize the bias of our results, we reviewed magnetic resonance imaging (MRI) findings of contributed patients for this study who scored severe kneeling pain to investigate whether any confounding risk factors participated. Two patients had BPTB autograft with a result of 7, 10 scores of kneeling pain, respectively. It consisted of complete ACL tear associated with features of posterior lateral corner syndrome and complicated Baker's cyst preoperatively in their MRI report. Additionally, one patient autografted with hamstring scored 10 (the maximum intensity) had high-grade anterior cruciate ligament tear associated with Posterior horn of medial meniscus oblique tear. No distinguished findings existed among patients who scored mild-moderate pain. Therefore, there is a correlation between the severity and the MRI abnormality findings.
A recent short-term study by Laxdal et al. showed that insignificant clinical differences could be found between two groups as well [22]. Similar findings published a long time in 1994 by Corry et al. found that the two grafts did not differ in terms of clinical stability, range of motion, and general symptoms, which consistent with our study findings [23]. Similarly, Biau et al. conducted a meta‑analysis of various studies concluded that insignificant differences between two grafts but recommended HS for patients who need jumping [24]. However, this might be attributed to the newer surgical techniques that performed, which leads to an insignificant difference in terms of complications. This perspective of the new surgical techniques should be taken into consideration and investigate extensively as BPTB is still a considerable option that would be advised for patients of certain ethnic origins and religions such as Muslims who need to kneel for prayer [25].
In addition, the potential muscle weakness following hamstring autograft for ACL reconstruction is concerned and investigated in many studies. Current literature results that surgeons need to balance adequate graft size and strength with the potential for donor-site morbidity when performing an ACL reconstruction with hamstring autografts. However, this aspect remains not conclusive yet as a hamstring function analysis by certain types of sports would be required to elucidate this issue, and it does not a concern aspect currently in our study [26[. Chee et al. conducted a meta-analysis recently that comparing the outcomes of BPTB grafts versus 4-strand hamstring autografts. They reported a significant negative effect in the aspects of anterior knee pain, kneeling pain, and extension deficit that did not support the use of BPTB grafts with favored the hamstring autograft rather than the BPTB graft for anterior knee pain and kneeling pain. Thus, it concluded that the 4-strand hamstring ACL reconstruction has comparable clinical results with the BPTB graft but with fewer postoperative complications [27[. However, other studies have found that an ACL reconstruction with a BPTB graft might be superior in aspects of stability and preferred to be used for the young athletic patient ]17, 28[. Therefore, both autografts are providing satisfactory outcomes in long-term means.
It is evident that ACL reconstruction surgeries performed by trained sport orthopedic surgeons have better outcomes than surgeries performed by general orthopods. In our study, there were three fellowship-trained sports orthopedic surgeons operated on all patients, which considered as a strength, but various surgical techniques performed, which might contribute to results bias. Although we enrolled a consecutive series of patients in our study to reduce the margin of selection bias, these patients were not randomized, which have been subject to selection bias. Thus, all patients involved were males and young with ACL rupture was sustained during participation in the athletic activity regardless the type of sport. At a 10-year follow-up, there were no gender differences regarding outcomes of failures, radiographic osteoarthritis, or overall IKDC scores [31]. Additionally, our study has been performed on a retrospective review basis, and as such, it carries inherent shortcomings. Finally, the sample size of patients is considered minimal compare to the original patients that have been operated due to loss of follow-up and strict inclusion & exclusion criteria we had, which potentially introduced bias to our results and reduce power for statistical significance and increase margin errors of data analysis.