Prevención de lesión de ligamento cruzado anterior en futbolistas: protocolo de campo e intervenciones eficientes

Abstract

The anterior cruciate ligament (ACL) injury is one of the most concerning. At the club level, because it leads to lose a player for the rest of the season, with its corresponding economic and performance implications. At the player level, due to its devastating consequences, such as the increased risk of suffering a second injury, not being able to compete at the previous level, or suffering early osteoarthritis. ACL injuries mainly occur in non-contact or indirect contact mechanisms with the injured leg (80%), commonly when performing either change of direction (COD) manoeuvres or landings from a jump in defensive situations, under uncertainty. Many risk factors have been related to ACL injury, although usually through weak associations due to the methodological limitations of the research designs traditionally used. Numerous intervention programs have been proposed for its prevention, although few have considered the characteristic context of football, resulting in very low implementation levels of such programs. The general aim of the thesis was to develop a comprehensive protocol to both evaluating the risk factors of ACL injuries of football players, as well as mitigating them through easily implementable preventative programs. For that purpose, the equipment, space and time restrictions frequently observed in football teams was always considered. To achieve the aim four scientific articles were carried out, of which 3 were published (articles 2, 3 and 4) in journals indexed in the Journal of Citation Reports. Article 1. Through this systematic review, we aimed to find all those tests that were developed to assess the risks of football players suffering an ACL injury through either landing or cutting manoeuvres. It was found that there is a wide variety of tests for this purpose both for landings (i.e. jumps with and without countermovement, drop landings, drop jumps (DVJ), running approach jumps, horizontal and consecutive jumps) and cuttings (i.e. of shallow, moderate, and sharp angulations), although very few have been appropriately associated with ACL injury, and where the levels of reliability of the metrics evaluated have rarely been offered. Article 2. The aim of the second systematic review was to compile all those exercisebased interventions, lasting more than 4 weeks, that were designed to reduce the incidence or risks of ACL injury in adult footballers. It was found that some warm-up programs, such as “FIFA 11+” or the “PEP Program” were effective in reducing the incidence, although the mechanisms by which they achieved this reduction are not clear. Other interventions based on technical modification, lumbopelvic strengthening, and balance showed promising effects, with resistance training programs proving effective, although difficult to implement in a football team context. Noteworthy is the scarcity of interventions evaluated for their ability to reduce the risks associated with the main ACL injury mechanisms, as well as the scarce and/or poor description of the programs and tests used (i.e., levels of reliability and supervisors of the intervention not reported, lack of clarity in the methods or inappropriate statistical approaches). Article 3. In this cross-sectional article, 42 semi-professional footballers were evaluated to determine if the Landing Error Scoring System (LESS) and Cutting Movement Assessment Score (CMAS) scales are reliable for assessing the quality of movement in DVJ and COD, respectively, as well as to elucidate whether they provide a shared ACL risk profile of the players. The results showed that they possess moderate to substantial levels of intra-observer reliability (ICC = 0.58-0.71), and substantial to almost perfect inter-observer reliability (ICC = 0.68-0.87). In addition, no relationship was found between the risk profile obtained for one scale and the other, suggesting that the risk of suffering an ACL injury is task-dependent. The second landing of the DVJ (LESS2) displayed a riskier pattern than the first (LESS1) (ES = 0.80-0.83) justifying the use of both, along with the CMAS, for a more detailed overview of the player's risk profile. Article 4. In the last article, the capability of the Safe Landing, a technique-modification intervention based on landings, plyometrics, and COD exercises, to improve the movement quality of DVJ and COD was evaluated through the LESS and CMAS scales. It was carried out for 6 weeks, 3 times a week, and included as part of the warm-up. The experimental group (EG, n = 15) showed moderate to large improvements in both landings of the DVJ (LESS1 and LESS2) and in the CMAS (p < 0.082, ղ2 = 0.137–0.272) compared to the control group (CG, n = 11), without a decline in performance in such manoeuvres, which remained stable pre- to post-intervention (p > 0.05, ES = 0.039– 0.420). Given the little equipment (i.e., cones and balls), and the short time required for its implementation (~9 minutes/session), the Safe Landing is proposed as an effective and easily implementable intervention (with compliance levels above 93%) to improve the movement quality of semi-professional football players. By this way, through this doctoral thesis, practitioners working in medical and performance staffs were provided by valid and reliable screening tools for the identification of their football players’ injury risk in the main mechanisms predisposing to ACL injury, as well as by efficient strategies for the effective reduction of these risks. To properly address the process, the approach was based on an attempt to keep a balance between the methodological rigor required by the scientific method and the reality that characterises the football’s context.