10th May 2011
7 - 9 April 2011, Monaco
Michal Hadala
Pre-season screening of core muscle balance and control tests in the lumbar spine in professional road cyclists. Can we prevent uncontrolled movement?
Hadala M,* ,** de Bernardo N,** Vera P,** Laíz C,** Barrios C,**,***
* Orthopaedics and Trauma Unit, Department of Surgery, University of Valencia, Valencia, Spain; **Physical Therapy and Exercise Center, Valencia, Spain; ***Institute for Research on Musculoskeletal Disorders, Valencia Catholic University, Valencia, Spain
Background: Pre-season screening is routinely promoted as part of either an injury prevention management approach or as a performance strategy. It seems that the clinical outcomes of asymptomatic function, normal range of joint motion (isolated testing) and normal muscle strength (isolated testing) are not adequate end points to prevent injury recurrence.
Objective: Assess core muscle balance and control tests in the lumbar spine using simple functional tests during low load activity (slow movements) and high load dynamic movements.
Design: Retrospective and descriptive study.
Setting: Professional road cyclists.
Patients: 51 elite road cyclists were functionally evaluated at the beginning of the 2010 cycling season. All injuries underwent by the racers during previous year seasons were recorded throughout a clinical oriented interview. Interventions: Specific assessment of the site (lower back and pelvis) and direction of uncontrolled movement, under low and high threshold loading within functionally orientated tasks. Three tests were conducted in the crook laying position: 1) double leg lift and lower, 2) single leg extension, 3) bridge + single leg extension. In two first tests the ‘Stabilizer’ pressure biofeedback unit (PBU) was used to measure the influence of the global muscle system on trunk stability under functional limb loading. Muscle functional extensibility of ilio-psoas, tensor fasciae late, anterior rectus femoris and hamstrings were assessed and registered in terms of the site and direction of uncontrolled movement. Main Outcome Measurements: Athletes with stiff hamstrings had more risk of overuse injuries (p<0.02). Weakness of the gluteus maximus in the right leg (p<0,001) and the left leg (p<0.005) correlated with uncontrolled movement in low back extension at high loading. Faulty movement in flexion with high load activity were found to be more frequent in cyclist with low back injuries (p<0.01). Results: Uncontrolled movement in lower back in low load test where diagnosed in flexion (57%, n:28/49) and extension (67%, n:33/49). Passive and active restriction of hamstrings in sitting showed significant correlation with impaired movement in lower back (low load) in flexion (p<0.05). Low back uncontrolled movement in high load were found in extension (90%, n:44/49). Impaired movements in pelvic girdle (70%) were due to rotation abnormalities with low loading and showed a statistically significant relationship with asymmetrical passive restriction of rectus anterior muscle (p<0.03). Conclusions: Muscle imbalance between hamstrings, hip flexors and weak hip extensors predispose professional cyclists to more overuse injuries and provoke uncontrolled movements in flexion, extension due to asymmetry to rotation. From this simple assessment, a specific preventive program can be developed and implemented to retrain lower back uncontrolled movements.
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Clinical patterns and injury exposure rates in elite road cycling are changing over the last decade
Barrios C, *, ≠ de Bernardo N,* Vera P,* Laíz C,* Hadala M,*,**
≠Institute for Research on Musculoskeletal Disorders, School of Medicine, Valencia Catholic University; *Physical Therapy and Exercise Center, Valencia; ** Orthopedics and Trauma Unit, Department of Surgery, Valencia University Medical School.
Background: The latest bicycle technical advances and the new training protocols might have an incidence of injury occurrence in professional cycling.
Objective: To analyze changes in injury incidence of a group of elite cyclist in active and compare the injury rates with those reported for an historical group.
Design: Epidemiologic retrospective study based on clinical oriented interviews
Setting: Clinical survey of all traumatic and overuse injuries occurred in male elite cyclists engaged in three professional teams.
Participants: The historical group (HG) consisted in 65 professional road cyclists surveyed from 1983 to 1995. Mean age, 25 years (range 21‑32). The current series (CS) included 51 elite cyclists with a mean age of 27 (19-36). The CS was studied from 2003 to 2009.
Main Outcome measures: Abbreviated Injury Scale (AIS) and the Ekstrand 3‑point scale for absence from sports activity. Injury exposure rates: injuries per racer, per year and per 1000 km of both competing and training.
Results: Traumatic injuries increased from 38.4% to 48.6%. However, AIS severe lesions decrease from 51.2% to 8%. Tendinopaties were the most common overuse injuries in the HG (41.5%). Contrary, 56.6% of overuse injuries were due to muscular lesions in the CS group. In HG cyclists, the injury rates for traumatic injuries were 0.54 per racer, 0.11 per year, and 0.003 per 1000 km of training and competition. The rates for overuse injury were 0.86 per racer, 0.17 per year, and 0.005 per 1000 km. In CS cyclists, injury rates for traumatic injuries were found to be higher: 0.98 per racer, 0.24 per year, 0.007 per 1.000 km. Overuse injury rates were 1.04 per racer, 0.26 per year, and 0.009 per 1.000 km.
Conclusions: Professional cyclists still in active are exposed to a double risk of traumatic injuries than those competing in the 80’s and 90’s. Exposure to overuse remains almost equal, but with a complete different clinical pattern imposed by the high incidence of muscular injuries.