Relationship between body dimensions and the diameter of a 4-strand ACLR graft

The objective of this study is to create a probability table outlining the chance of preparing a 'doubled semitendinosus and doubled gracilis' (ST×2 + G×2) graft for anterior cruciate ligament reconstruction (ACLR) with minimum diameters of 7 and 8 mm, based on body height (BH) and body weight (BW).

A retrospective study was conducted on patients who underwent hamstring harvesting between 2008 and 2021. Patients eligible for inclusion were those who (1) were skeletally mature at the time of ACLR, (2) underwent ACLR using a medial hamstring autograft, (3) had both semitendinosus and gracilis tendons harvested and (4) were of the same ethnicity (Chinese). The diameter of the 'ST×2 + G×2' graft was recorded in 0.5 mm increments. A probability table was developed using BH intervals of 5 cm and BW increments of 10 kg.

The study included a total of 536 skeletally mature patients, consisting of 444 males and 92 females. The average BH and BW were 171 ± 8 cm and 70.9 ± 12.5 kg, respectively. The average diameter of the 'ST×2 + G×2' graft was 8.6 ± 0.9 mm. The preparation of a 4-strand ACLR graft with a 7 mm diameter was almost always achievable in males (99.1%). In contrast, the successful preparation of a 7 mm graft was not feasible in females weighing less than 40 kg. The likelihood of successfully preparing a 4-strand graft with an 8 mm diameter was low for males with a BH < 160 cm and a BW < 60 kg. Regardless of BH, the chance of successfully preparing an 8 mm diameter graft in females was high if their BW exceeded 60 kg.

A significant positive association was observed between the diameter of 'ST×2 + G×2' and male sex, BH and BW. The likelihood of successfully preparing a 4-strand graft with a minimum diameter of 8 mm was low for male patients shorter than 160 cm and weighing less than 60 kg. Meanwhile, it is impossible to successfully prepare a 4-strand ACLR graft with a minimum diameter of 7 mm for female patients weighing less than 40 kg.

Level IV.