DO GENERALIZED JOINT HYPERMOBILITY OR GENU RECURVATUM INFLUENCE OUTCOMES AFTER ISOLATED PRIMARY HAMSTRINGS ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION?

The primary purpose of this study was to assess whether generalised joint hypermobility or genu recurvatum influence the objective clinical, functional performance, and quality of life outcomes of patients following isolated primary hamstring autograft anterior cruciate ligament reconstruction (ACLR). Patients (n=1587) were included following an isolated primary ACLR with STG autograft. Data was prospectively collected between 2010-2015 from a single center. Demographic and clinical information were collected including age, sex, body mass index (BMI), generalized joint hypermobility (GJH), and genu recurvatum (GR). Functional tests including single-leg balance and the 4 single-leg hop tests were used to assess limb symmetry indices (LSI) at 2-years. Patients completed the ACL-QoL questionnaire pre-operatively and at 1- and 2-years post-operative. Descriptive statistics were used to assess patient demographics, surgical details, ACL graft injury rate, LSI, and ACL-QoL scores. Differences in ACL-QoL scores from pre- to post-operative were assessed using a one-way ANOVA. Descriptive statistics, paired t-tests and one-way ANOVA were utilized to assess between-groups differences. The study cohort included 859 males (54.1%) and 728 females (45.9%), with a mean age of 30 years (SD ±10.4), and mean BMI of 25 (SD ±3.9). Positive GJH (Beighton score ≥ 4) was assessed for n=687 (43.3%) and genu recurvatum measured at ≥10° for n=728 (45.9%). Mean graft diameter was 7.6mm, and intra-operative assessment revealed 67.8% of knees has meniscal injuries and 31.5% had chondral injuries. At 2-years post-operative n=1292 patients had completed follow-up (81.4%). ACL graft injuries were confirmed in n=59 knees (3.7%), with n=42 in the group without GJH (4.4%) and 17 in the positive GJH group (2.7%) (n/s). The 4 single-leg hop tests demonstrated an LSI of 98.9% at 2-years with no significant differences for patients with or without GJH or GR. Mean ACL-QoL scores prior to surgery were 28.8/100 (SD ±13.7), with evidence of statistically significant increases to 71.0 (SD ±19.5) at 1-year, and 77.2 (SD ±19.4) at 2-years post-operative (p < 0 .001). There were no differences in ACL-QoL scores for patients with or without GJH or GR (n/s). In this study assessing outcomes 2-years post-operative, the follow-up rate was 81.4% and the number of ACL graft injuries was 59/1587 (3.7%). Patients with generalized joint hypermobility or genu recurvatum did not demonstrate any statistically significant differences in rates of reinjury, clinical knee laxity, functional testing performance, or ACL-QoL scores. (Further assessment of the variables associated with graft failure in this cohort using multivariate regression will be undertaken).