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

Table 1 Incision direction/length, neurological injury, area of hypoesthesia

Ref.	Direction/length of incision	Prevalence of IPBSN injury	Area of hypoesthesia
Keyhani et al[23], 2019	Vertical: 3.8 cm; Oblique: 2.7 cm	IPBSN 40%; Vertical 56.8%; Oblique 25%	Vertical 34.2 cm2; Oblique 9.6 cm2
Mousavi et al[25], 2018	Vertical: 5.1 cm; Oblique: 3.8 cm	IPBSN 83%; Vertical 95.8%; Oblique 61.3%	Vertical 59.9 cm2; Oblique 11.5 cm2
Sabat et al[29], 2012	Vertical: 4.1 cm; Oblique 3.8 cm	1IPBSN 48%; 1Vertical 76%; 1Oblique 32%	1Vertical: 44.6 cm2; 1Oblique: 14.4 cm2
Joshi et al[23], 2016	Vertical: 3 cm; Oblique: 3 cm	IPBSN 21.1%; Vertical 25%; Oblique 16.36%	N/M
Luo et al[19], 2007	Vertical 3.4 cm; Oblique: 3.3 cm	IPBSN 48%; Vertical 65.7%; Oblique 24%	Vertical: 48 cm2; Oblique: 8.4 cm2
Sharaby et al[29], 2019	Vertical 5 cm; Oblique: 5.2 cm	IPBSN: 69.2%; Vertical: 39.5%; Oblique: 24%	N/M
Mahmood et al[21], 2020	Oblique: 2.9 cm	IPBSN: 24%	Oblique: 3.9 cm2
Figueroa et al[28], 2008	Vertical: 1.8 cm	IPBSN: 77%	Vertical: 3.6 cm2
Sanders et al[15], 2007	Vertical: 1.5-2 cm	IPBSN: 19%	N/M
Ochiai et al[24], 2017	Vertical: 1.8-2.5 cm	21.1%	N/M

¹Six months postoperatively.

IPBSN: Infrapatellar branch of the saphenous nerve (total prevalence of hypoesthesia over the infrapatellar branch of the saphenous nerve distribution measured clinically); N/M: No mention.

Table 2 Advantages of using the posteriomedial approach to harvest hamstring tendons

Advantages of the posteriomedial hamstring harvesting approach over the anteromedial approach
Better cosmetic appearance
Lower risk of infrapatellar branch of the saphenous nerve injury
Direct visualization of the bands attached to the hamstring tendons which facilitate their release
Lower risk of premature amputation of the harvested grafts
Easier approach when harvesting of a single tendon is desired
Lower risk of medial collateral ligament injury
Smaller incision for the tibial drill guide with the advantage of placing the incision in the desired location

Table 3 Hamstring graft preparation techniques: summary of results

Graft preparation
Ref.	Study design	Results/conclusion
Ardern et al[47], 2009	Systematic review	ST-GT autograft have a significantly higher deficit in isometric strength at knee flexion ≥ 70°. Significant standing knee flexion angle deficit in the ST-GT autograft group.
Sharma et al[46], 2015	Meta-analysis	ST-GT group had a significantly higher isokinetic hamstring strength deficit at 60°. ST-GT group had a significantly higher isometric hamstring strength deficit at 90°, 105°, 110°. ST-GT group had a significantly higher standing knee flexion angle deficit.
Chin et al[48], 2018	Meta-analysis	ST-GT group had a significantly increased s deficit in isokinetic peak torque when compared with ST group for flexion at 60°/s at 2-yr follow-up, and flexion at 180°/s at 1- and 2-yr follow-up.
Tashiro et al[49], 2003	RCT	ST-GT group had a significantly increased deficit in isokinetic peak torque measured at knee flexion 60°/s at 80°, 90°, 110° when compared with ST group at 18 mo postoperatively. ST-GT group had a significantly higher isometric hamstring strength deficit at 70° measured in sitting position at 18 mo postoperatively. ST-GT group had a significantly higher isometric hamstring strength deficit at 70° and 90° measured in prone position at 18 mo postoperatively. Both groups showed significant isometric and isokinetic strength deficit when compared to preoperative measures.
Nakamura et al[50], 2002	Consecutive sample, case–control study	ST-GT group had a significantly higher standing knee flexion angle deficit. Decreased isokinetic torque at 90° in both groups.
Hu et al[51], 2020	Retrospective comparative	ST-GT group had a significantly higher isometric hamstring strength deficit at 90° flexion. Significant difference in the KOOS pain score.
Adachi et al[52], 2003	Prospective review	ST-GT group had a significantly higher standing knee flexion angle deficit.
Yosmaoglu et al[53], 2011	Prospective review	ST-GT group had a significantly higher hamstring isokinetic flexion strength deficit at 60°/s.
Carter et al[54], 1999	RCT	No difference in isokinetic strength deficit between ST-GT and ST groups, measured at 180°/s and 300°/s. Majority of patients had activity limitation at 6 mo postoperatively.
Karimi-Mobarakeh et al[55], 2014	RCT	No difference in isometric strength deficit between ST-GT and ST groups, measured at 90° flexion, extension, adduction, or abduction. No difference in patient outcome measures between ST-GT and ST groups.
Gobbi et al[56], 2005	RCT	ST-GT group had a significantly higher hamstring isokinetic internal and external rotation strength deficit at 60°/s.
Inagaki et al[57], 2013	Prospective comparative	No difference in isokinetic strength deficit between ST-GT and ST groups, measured at 60°/s. No difference in anterior laxity, or knee ROM. No difference in patient reported outcomes.
Segawa et al[58], 2002	Prospective study	ST-GT group had a significantly higher hamstring isokinetic internal rotation at 120°/s and 30°/s.
Ardern et al[59], 2010	Retrospective comparative	No difference in isometric strength deficit between ST-GT and ST groups, at 30°, 90°, or 105°. No difference in isokinetic strength deficit between ST-GT and ST groups, measured at 60°, 90°, and 105° or 60°/s and 180°/s. No difference in standing nee flexion angle between ST-GT and ST groups.
Barenius et al[60], 2013	Retrospective study	No difference in isokinetic strength deficit between ST-GT and ST groups, at 20°, and 90° measured at 60°/s. No difference in isometric strength deficit between ST-GT and ST groups at 90°.
Lipscomb et al[61], 1982	Retrospective study	No difference in isokinetic strength deficit between ST-GT and ST groups, measured at 60°/s and 240°/s.

ST-GT: Semitendinosus and gracilis; ST: Semitendinosus; RCT: Randomized control trial; KOOS: Knee osteoarthritis and outcomes score.

Table 4 Hamstring graft fixation techniques: summary of results

Graft fixation
Ref.	Study design	Results/conclusion
Boutsiadis et al[72], 2018	Cohort study; level of evidence, 3	No difference in postoperative anterior knee laxity at a minimum 2 yr follow-up between interference screw and ALSF device for femoral fixation. The preoperative pivot shift is the only significant risk factor for postoperative residual anterior knee laxity more than 3 mm.
Shanmugaraj et al[81], 2020	Systematic review and meta-analysis	No significant differences in complication rates between femoral press-fit and femoral metal interference screw fixation. Press-fit fixation had significant improvements in functional outcome scores postoperatively and had significantly reduced postoperative bone tunnel enlargement compared to bioabsorbable fixation.
Debieux et al[70], 2016	Review	No difference in self-reported knee function and levels of activity between bioabsorbable and metallic interference screws. Bioabsorbable screws may be associated with more overall treatment failures, including implant breakage during surgery.
Han et al[62], 2012	Level II, systematic review of level I and II studies	At a minimum of 2 yr follow-up, comparable outcomes based on objective IKDC, Lysholm knee scale, and Tegner activity level survey results were found, as well as anterior knee joint laxity measurements between intra-tunnel and extra-tunnel fixation. Intra-tunnel fixation began jogging/running earlier than patients who received extra-tunnel fixation. However, return to sports timing was comparable between the groups.
Hu et al[80], 2017	Systematic review and meta-analysis	The significantly decreased instrumented side-to-side anterior–posterior laxity difference achieved by cross-pin transfixation appears to be of limited clinical significance when compared with interference screw fixation in primary hamstring ACLR.
Fu et al[73], 2020	Systematic review and meta-analysis	Suspensory cortical button fixation was not clinically superior to interference screw fixation in functional outcomes, knee laxity measured with arthrometer, or re-rupture rate. The advantage of using suspensory cortical button fixation was that a thicker graft could be used for reconstruction, and brought less tibia tunnel widening compared with bioabsorbable interference screw fixation.
Saccomanno et al[63], 2014	Systematic review of randomized controlled trials	There are no short- to medium-term differences in knee-specific outcome measures between cortical button femoral graft fixation and suspensory transfemoral fixation In addition, radiological evidence of tunnel widening does not seem to affect short- to medium-term clinical outcomes.
Speziali et al[79], 2014	Systematic review of level I and II therapeutic studies	Side-to-side anterior-posterior tibial translation was 1.9 ± 0.9, 1.5 ± 0.9, 1.5 ± 0.8, 2.2 ± 0.4 mm for metallic interference screw, bioabsorbable screw, cross-pin and suspensory device, respectively. Rate of failure was 6.1%, 3.3%, 1.7% and 1.2% for bioabsorbable interference screw, metallic interference screw, cross-pin and suspensory device, respectively.
Baumfeld et al[74], 2008	Retrospective review	There was significantly more femoral tunnel widening associated with the use of the endobutton suspensory fixation system compared to the use of double cross-pins fixation.
Milano et al[64], 2006	Biomechanical analysis	Corticocancellous suspension fixation offer the best results in terms of graft elongation, fixation strength, and stiffness. Cancellous suspension fixation was homogeneous with other suspension fixation mechanisms but significantly weaker. Interference screws, both metallic and absorbable, showed low failure load but greatest graft elongation.
Sabat et al[75], 2011	Level II, prospective comparative study	Femoral tunnel widening was significantly less in the Transfix group compared with the endobutton group.
Saygi et al[76], 2015	Therapeutic case series, level IV	Undersize drilling technique is preferred in button fixation in order to reduce tunnel widening and improve clinical satisfaction.
Shen et al[77], 2008	Biomechanical comparison study	The cross-pin fixation is a good option for early aggressive rehabilitation following ACL reconstruction due to has significantly less displacement of femur–graft–tibia complex than that of endobutton-CL fixation in response to the cyclic loading test.
Vertullo et al[78], 2019	Controlled laboratory study	The suspensory fixation constructs exhibited small yet statistically significant biomechanical differences among each other. Tibial screw fixation had lower ultimate failure load and higher total elongation.

ALSF: Adjustable-loop suspensory fixation; IKDC: International Knee Documentation Committee; ACLR: Anterior cruciate ligament rupture; ACL: Anterior cruciate ligament; CL: Cruciate ligament.