New aspects on timing and graft morbidity in anterior cruciate ligament reconstruction

Abstract: The aim of this thesis was to investigate the effect of different surgical techniques on knee function and outcomes after an anterior cruciate ligament (ACL) reconstruction (ACLR). In Study I, 70 patients with a Tegner level of six or more were assessed after randomisation between acute ACLR (within 8 days after the injury) and delayed ACLR (after normalised range of motion [ROM] 6–10 weeks after the injury) using a four-strand semitendinosus tendon graft. The primary endpoint was range of motion at three months, and in this first study the patients were followed up for six months. The results for stiffness, laxity, functional tests and functional scores were comparable for both groups. Patients who underwent delayed surgery had more muscle hypotrophy in the early phase of the rehabilitation process. In Study II, 70 patients from the same randomised controlled trial as in Study I were assessed to compare total number of sick-leave days taken during the first year following an ACL rupture in those undergoing acute and delayed reconstruction as a means of measuring indirect socioeconomic costs. Acute reconstruction resulted in significant fewer sick-leave days during the first year after the injury. Acute and delayed ACL reconstruction provided similar clinical outcomes after 12 months with no significant differences. In Study III, the patients in Study I were assessed at 24 months post-surgery. Twelve patients were lost to follow-up, six in each group. While no significant differences regarding outcome measurements between the groups could be found, both groups showed better functional outcome scores compared to the Swedish Knee Ligament Register (SKLR). In Study IV, 140 patients were randomised between ipsilateral (IL) and contralateral (CL) four-strand semitendinosus tendon autograft and followed up for 24 months. The aim was to compare muscle strength and patient reported outcomes following ACLR using a semitendinosus (ST) graft from the IL leg compared to a graft from the CL leg and the primary endpoint was isometric hamstring strength at 6 months The results did not show any measurable subjective differences. The CL group showed early symmetrical strength between the limbs, while the IL group stayed asymmetrical during the whole trial with significant differences between the groups in both isometric and isokinetic strength. In conclusion, acute ACLR can be performed safely without an increased risk of developing stiffness, and a reconstruction performed before recurrent giving ways occur increases the likelihood of achieving better functional scores. There is also, from a society viewpoint, a potential economic benefit to identifying individuals who would benefit from acute ACL reconstruction. Using a CL autograft is a safe option and could have benefits regarding regaining symmetrical strength between the limbs