Igor Setuain

Vertical jumping biomechanical evaluation through the use of an inertial sensor-based technology

ABSTRACT Progress in micro-electromechanical systems has turned inertial sensor units (IUs) into a suitable tool for vertical jumping evaluation. In total, 9 men and 8 women were recruited for this study. Three types of vertical jumping tests were evaluated in order to determine if the data provided by an IU placed at the lumbar spine could reliably assess jumping biomechanics and to examine the validity of the IU compared with force plate platform recordings. Robust correlation levels of the IU-based jumping biomechanical evaluation with respect to the force plate across the entire analysed jumping battery were found. In this sense, significant and extremely large correlations were found when raw data of both IU and force plate-derived normalised force–time curves were compared. Furthermore, significant and mainly moderate correlation levels were also found between both instruments when isolated resultant forces’ peak values of predefined jumping phases of each manoeuvre were analysed. However, Bland and Altman graphical representation demonstrated a systematic error in the distribution of the data points within the mean ±1.96 SD intervals. Using IUs, several biomechanical variables such as the resultant force–time curve patterns of the three different vertical jumps analysed were reliably measured.

Biomechanical jumping differences among elite female handball players with and without previous anterior cruciate ligament reconstruction: a novel inertial sensor unit study.

Persistent biomechanical and jumping capacity alterations have been observed among female athletes who have sustained anterior cruciate ligament (ACL) injuries. The purpose of this study was to examine if biomechanical jumping differences persist among a cohort of elite female handball players with previous ACL reconstruction several years after return to top-level competition. In order to achieve this goal, a direct mechanics simplified analysis by using a single Inertial Sensor Unit (IU) was used. Twenty-one elite female (6 anterior cruciate ligament reconstructed and 15 uninjured control players) handball players were recruited and evaluated 6.0 ± 3.5 years after surgical anterior cruciate ligament reconstruction. Bilateral and unilateral vertical jumps were performed to evaluate the functional performance and a single inertial sensor unit was employed in order to collect 3D acceleration and 3D orientation data. Previously ACL-reconstructed analysed athletes demonstrated significant (p < 0.05) alterations in relation to the three-dimensional axis (X–Y–Z) supported accelerations and differing jump phase durations, including jumping performance values, in both bilateral and unilateral jumping manoeuvres several years after ACL reconstruction. Identification of the encountered deficits through the use of an IU devise could provide clinicians with a new reliable tool for movement analysis in a clinical setting.

Sprint mechanics evaluation using inertial sensor-based technology : A laboratory validation study

Advances in micro‐electromechanical systems have turned magnetic inertial measurement units (MIMUs) into a suitable tool for vertical jumping biomechanical evaluation. Thus, this study aimed to determine whether appropriate reliability and agreement reports could also be obtained when analyzing 20‐m sprint mechanics. Four bouts of 20‐m sprints were evaluated to determine whether the data provided by a MIMU placed at the lumbar spine could reliably assess sprint mechanics and to examine the validity of the MIMU sensor compared to force plate recordings. Maximal power (P0), force (F0), and velocity (V0), as well as other mechanical determinants of sprint performance associated with the force‐velocity, power‐velocity, and ratio of forces‐velocity, such as applied horizontal force loss (Sfv) and decrease in ratio of forces (Drf), were calculated and compared between instrumentations. Extremely large‐to‐very large correlation levels between MIMU sensor‐based sprint mechanics variables and force plate recordings were obtained (mean±SD, force plate vs MIMU; V0, 8.61±0.85 vs 8.42±0.69; F0, 383±110 vs 391±103; P0, 873±246 vs 799±241; Sfv, −44.6±12.7 vs −46.2±10.7), ranging from 0.88 to 0.94, except for Drf, which showed weak‐to‐moderate correlation level (r=.45; −6.32±1.08 vs −5.76±0.68). Step‐averaged force values measured with both systems were highly correlated (r=.88), with a regression slope close to the identity (1.01). Bland and Altman graphical representation showed a no random distribution of measured force values. Finally, very large‐to‐extremely large retest correlation coefficients were found for the intertrial reliability of MIMU measurements of sprint performance variables (r value ranging from .72 to .96). Therefore, MIMUs showed appropriate validity and reliability values for 20‐m sprint performance variables.

Acceleration and Orientation Jumping Performance Differences Among Elite Professional Male Handball Players With or Without Previous ACL Reconstruction: An Inertial Sensor Unit-Based Study

Handball is one of the most challenging sports for the knee joint. Persistent biomechanical and jumping capacity alterations can be observed in athletes with an anterior cruciate ligament (ACL) injury. Commonly identified jumping biomechanical alterations have been described by the use of laboratory technologies. However, portable and easy‐to‐handle technologies that enable an evaluation of jumping biomechanics at the training field are lacking.

Differential Effects of 2 Rehabilitation Programs Following Anterior Cruciate Ligament Reconstruction

CONTEXT The muscular function restoration related to the type of physical rehabilitation followed after anterior cruciate ligament reconstruction (ACLR) using autologous hamstring tendon graft in terms of strength and cross-sectional area (CSA) remain controversial. OBJECTIVE To analyze the CSA and force output of quadriceps and hamstring muscles in subjects following either an Objective Criteria-Based Rehabilitation (OCBR) algorithm or the usual care (UCR) for ACL rehabilitation in Spain, before and 1 year after undergoing an ACLR. DESIGN Longitudinal clinical double-blinded randomized controlled trial. SETTING Sports-medicine research center. PATIENTS 40 recreational athletes (30 male, 10 female [24 ± 6.9 y, 176.55 ± 6.6 cm, 73.58 ± 12.3 kg]). INTERVENTION Both groups conducted differentiated rehabilitation procedures after ACLR. Those belonging to OCBR group were guided in their recovery according to the current evidence-based principles. UCR group followed the national conventional approach for ACL rehabilitation. MAIN OUTCOME MEASURES Concentric isokinetic knee joint flexor-extension torque assessments at 180°/s and Magnetic Resonance Imaging (MRI) evaluations were performed before and 12 months after ACLR. Anatomical muscle CSA (mm2) was assessed, in Quadriceps, Biceps femoris, Semitendinous, Semimembranosus, and Gracilis muscles at 50% and 70% femur length. RESULTS Reduced muscle CSA was observed in both treatment groups for Semitendinosus and Gracilis 1 year after ACLR. At 1-year follow-up, subjects allocated to the OCBR demonstrated greater knee flexor and extensor peak torque values in their reconstructed limbs in comparison with patients treated by UCR. CONCLUSIONS Objective atrophy of Semitendinosus and Gracilis muscles related to surgical ACLR was found to persist in both rehabilitation groups. However, OCBR after ACLR lead to substantial gains on maximal knee flexor strength and ensured more symmetrical anterior-posterior laxity levels at the knee joint.

A protocol for a new methodological model for work-related shoulder complex injuries: from diagnosis to rehabilitation

BackgroundWork-related injuries of the shoulder complex represent a challenge for clinicians because of the large variety of clinical entities involved and the broad anatomic structures that can be affected. Furthermore, commonly performed orthopedic tests have demonstrated limited accuracy for diagnosing the injury despite considerable research efforts. The aim of this study protocol is therefore to describe a comprehensive approach integrating both a clinical- and functional status-based pathology and an adapted rehabilitation prescription.Methods/DesignA longitudinal cohort study will be performed at the Department of Rehabilitation and Medical Assistance of a mutual insurance society for work-related injury management in Spain (Mutua Navarra, Pamplona, Navarra Spain). Patients will be attended by an occupational physician who specializes in work-related injuries and is part of the project team that will systematically visit all the participants. After the medical diagnosis and any requested supplementary evaluations (i.e., radiological examinations), the patients will be referred to the rehabilitation service. Before the physiotherapeutic rehabilitation program is initiated, the patients will undergo a comprehensive functional screening at the biomechanics laboratory. Using a decision-making scheme, the identified functional deficits will be used to customize the individual rehabilitation plan.DiscussionThe proposed objective criteria-based shoulder diagnosis and rehabilitation model could be a new effective strategy for minimizing the time required to regain functional capacity and recover from symptoms among patients with work-related shoulder injuries.Trial registrationThe study protocol has been registered on Clinical Trials.gov as NCT02732002 (April 10th 2016).

A Biomechanical Perspective on Rehabilitation of ACL Injuries in Handball

Handball sport is a good example of a highly strenuous body-contact team sport with a strong emphasis on running speed, jumping, abrupt changes in direction and throwing in which enormous forces are developed around the knee joint. Due to handball’s intrinsic need for abrupt changes in direction and unplanned action management, as well as the high game intensity, anterior cruciate ligament (ACL) rupture is one of the most frequent devastating injuries among handball players. Moreover, an incomplete or insufficient rehabilitation program following an ACL injury may increase the risk of both re-injury and injury of the unaffected contra lateral knee. Thus, the identification of functional, biomechanical and neuromuscular deficits before discharging these patients from rehabilitation appears to be crucial for ACL re-injury prevention in this population. However, the scientific literature has still several concerns that despite previous conscientious scientific efforts made, remains sparse and to be clarified yet. This cornerstones are: the optimums rehabilitation type for successful ACL injury recovery, and the gold standard for an evidence based, objective and clinically feasible criteria for a save and competitive return to play after the suffering of this knee injury. Through a biomechanical approach to ACL injury management this chapter aims to help the clinician to understand the main biomechanical and functional aspects to deal when treating with an ACL injured handball player.

Short-term effects of manipulative treatment versus a therapeutic home exercise protocol for chronic cervical pain: A randomized clinical trial

BACKGROUND While both manipulative treatment and physical exercises are used to treat cervical pain, it remains unclear which is most effective. OBJECTIVE To compare the short-term effects of high-velocity, low-amplitude manipulation techniques (MT) with those of home-exercise (HE) with stretching and low-intensity (10% of max) isometric contractions on pain and function. METHODS Single-blind randomized clinical trial was performed. A total of 27 asymptomatic subjects were randomly assigned to 2 groups: manipulation techniques (MT, n= 13) and home exercise (HE, n= 14). The visual analogue scale (VAS); neck disability index (NDI); pressure pain thresholds; cervical spine range of motion and electromyography during the cranio-cervical flexion test was measured before and one week after the intervention. RESULTS After the intervention, both groups showed improved (P< 0.05) NDI and VAS scores and flexion in both rotation ranges compared with the pre-intervention values. For the NDI, pain intensity, and neck flexion, the effects sizes were large; for the majority of the other measurements, the effect sizes were small to moderate. The MT group showed significantly better results than the HE group for 2 out of 17 tests. CONCLUSIONS Both interventions improved function and pain after one week, with only marginal between-group differences in favor of MT.