Graft choice did not predict re-tear risk in a national cohort of footballers

The choice of which tendon to use as a graft in anterior cruciate ligament (ACL) reconstruction is one of the more debated decisions in knee surgery, and it is often made on the assumption that graft type shapes the odds of a second rupture. A nationwide Swedish cohort published in the British Journal of Sports Medicine on 3 September finds that, among football players, it largely does not [s1].

What the study did

The researchers linked two national registers — the Swedish Knee Ligament Registry and the Swedish Football Association — to identify every primary ACL reconstruction performed in registered football players in Sweden between 2014 and 2023 [s1]. That produced a cohort of 10,693 players, of whom 6,238 (58%) returned to competition, defined as playing in at least one official match [s1]. Mean age was 22±7 years and mean follow-up was 5.2±2.9 years [s1].

The question was whether autograft type — hamstring, patellar or quadriceps tendon — was associated with the risk of two outcomes: revision reconstruction of the same knee, and a later reconstruction of the opposite (contralateral) knee [s1]. The analysis used sex-stratified, cause-specific Cox models adjusted for age and pre-injury level of play, with hamstring tendon as the reference graft [s1].

The main finding is a null

Among players who returned to competition, revision reconstruction of the index knee occurred in 232 women (10.8%) and 349 men (9.2%), with no association between graft type and revision [s1]. In other words, once age and playing level were accounted for, the tendon a surgeon chose did not independently predict whether the reconstruction failed and had to be redone.

That is a useful null. Graft selection carries real trade-offs — in donor-site pain, in recovery, in the technical demands of the operation — but this cohort does not support the idea that one graft type protects a footballer against re-rupture of the reconstructed knee.

Where a signal did appear

The picture was not entirely flat. Contralateral reconstruction — a new tear in the other knee — occurred in 263 women (12.2%) and 264 men (6.9%) [s1]. Among women, quadriceps tendon grafts were associated with a higher hazard of contralateral reconstruction than hamstring grafts (hazard ratio 1.98, 95% CI 1.17 to 3.36) [s1].

This finding needs to be read carefully. It concerns the opposite knee, which the graft choice does not mechanically touch, so it is not a straightforward statement that quadriceps grafts fail more often. The authors report that no graft-specific differences held up in age-restricted sensitivity analyses or in the full cohort [s1]. A single association in one subgroup, not consistent across the study's other analyses, is the kind of result that flags a hypothesis rather than settles one.

What did predict a second reconstruction

Across the analyses, the most consistent correlates of a subsequent ACL reconstruction were not surgical at all. Younger age and a higher pre-injury level of play were repeatedly associated with greater risk of a later reconstruction, whether of the index or the contralateral knee [s1]. That fits a straightforward mechanism: younger, higher-level players return to more, and more intense, football, and exposure to the sport is itself a risk factor for injury.

Limits

This is a single national registry analysis, and its strengths and weaknesses both flow from that design. Register linkage captures a whole country's reconstructions rather than a selected trial sample, but it cannot randomise which graft a patient received; surgeons chose grafts for reasons the registry does not fully record, and those reasons could track with injury risk. The outcome is a second operation, not every re-injury — players who tore a graft but did not have revision surgery would not be counted. And the cohort is footballers in one country, so the findings should not be read across to other sports or populations.

What the study does offer is a large, population-level check on a common clinical assumption. For football players specifically, it suggests that when a reconstruction fails, the graft type chosen at the first operation is not the lever that decides it — and that a player's age and level of play tell you more about their risk than the tendon in their knee.

Sources

• Graft type is not associated with revision ACL reconstruction in football players: a nationwide cohort analysis — British Journal of Sports Medicine, 2026-09-03