Effects of the open Latarjet procedure on shoulder kinematics and periscapular muscle activity three months postoperatively.

BACKGROUND: The debate surrounding the influence of the open Latarjet procedure on postoperative scapular motions persists, and there is no evidence regarding its effects on periscapular muscle activation. This study aimed to assess the short-term influence of open Latarjet procedure on scapular kinematics and periscapular muscle activity during arm raising and lowering based on comparisons between patient and healthy athletes. METHODS: 22 healthy male athletes and 22 male athletes scheduled for glenohumeral stabilization surgery by open Latarjet procedure were included. Scapular kinematics, periscapular muscle activities and shoulder-related quality of life were recorded prior to surgery and 3 months postoperatively for the Latarjet group. For the healthy group, same assessments were performed 3 months apart. Bilateral differences in both scapular kinematics and periscapular muscle activation ratios, and Western Ontario Shoulder Instability (WOSI) index were defined as dependent variables. RESULTS: Scapular kinematics of the operated shoulder, namely scapular upward/downward rotation, internal/external rotation and anterior/posterior tilt recorded between 20° and 120° of humerothoracic elevation, showed no alterations 3 months post-surgery (p>0.05), and did not differ from those observed in healthy athletes (p>0.05). Similarly, all periscapular muscle activations were not different within time and between groups (p>0.05). WOSI index of the operated shoulder was significantly improved postoperatively (871.9 ± 443.7 vs. 1346.3 ± 552.3) but remained higher than the WOSI indices of the non-operated shoulder or those of the healthy group (52.7±75.6). CONCLUSION: This study emphasizes the short-term effects of the open Latarjet procedure, demonstrating an improvement in the shoulder-related quality of life 3 months after surgery. Notably, during this period, both kinematics and periscapular muscle activity remained consistent, and similar to the patterns observed for healthy athletes.

Effects of Repeated High-Intensity Effort Training or Repeated Sprint Training on Repeated High-Intensity Effort Ability and In-Game Performance in Professional Rugby Union Players.

ABSTRACT: Glaise, P, Rogowski, I, and Martin, C. Effects of repeated high-intensity effort training or repeated sprint training on repeated high-intensity effort ability and in-game performance in professional rugby union players. J Strength Cond Res 38(5): 932-940, 2024-This study investigated the effects of repeated high-intensity efforts (RHIE) training compared with repeated sprint exercise (RSE) training on RHIE ability (RHIEa) and in-game performance in professional rugby union players. Thirty-nine, male, professional, rugby union players were randomly assigned to 3 training groups (RHIE training, RSE training, and control). Repeated high-intensity effort ability and high-intensity effort characteristics (including sprints, acceleration, and contact efforts) during official games were measured before and after a 10-week specific (RHIE, RSE, or control) training period. The results of this study showed that concerning RHIEa, both the RHIE and RSE training significantly increased the players' average sprint velocity ( p < 0.001, d = -0.39 and p < 0.001, d = -0.53 respectively), average sled push velocity (ASPV; p < 0.001, d = -0.81 and p = 0.017, d = -0.48 respectively), and RHIE score ( p < 0.001, d = -0.72 and p < 0.001, d = -0.60 respectively). Repeated high-intensity effort training trended in a smaller increase in average sprint velocity than RSE training, a larger increase in ASPV, and a similar increase in RHIE score. Concerning in-game high-intensity efforts, both the RHIE and RSE training produced significant improvements in the number of sprints ( p = 0.047, d = -0.28 and p < 0.001, d = -0.47 respectively), total distance ( p < 0.001, d = -0.50 and p = 0.002, d = -0.38 respectively), the number of accelerations ( p < 0.001, d = -0.37 and p = 0.003, d = -0.32 respectively), and contact rate ( p < 0.001, d = -0.97 and p = 0.020, d = -0.28 respectively). Conversely, the magnitude of the increase in contact rate was almost twice as high in RHIE compared with RSE training. To conclude, the findings of this study were that both RSE and RHIE training are effective methods for developing RHIEa and in-game high-intensity efforts in professional rugby union. In practical applications, as the gains in certain abilities and game performance data differed depending on the training method chosen, we suggest that coaches choose the most appropriate method according to the profile of the players, their position, and the style of play they want to develop.

Effects of an 8-week multimodal program on thoracic posture, glenohumeral range of motion and serve performance in competitive young tennis players.

Introduction: Intensive tennis practice is known to generate sport-specific adaptations at the shoulder region and influence the sagittal spinal curvature. However, increased thoracic kyphosis decreases the shoulder functional capacity, which could limit tennis performance. Therefore, the aim of this study was to investigate the effects of an 8-week multimodal program on thoracic posture, glenohumeral range of motion, and serve performance in competitive young tennis players. Methods: Eighteen male and four female players (age: 16.0 ± 2.4 years, height: 170.7 ± 11.0 cm; mass: 62.1 ± 11.5 kg; International Tennis Number: 3-4) performed their regular training during 8 weeks, which was used as a reference period, and implemented a multimodal program including stretching, strengthening, and myofascial release exercises, four times per week during 8 additional weeks, which corresponded to the intervention period. The thoracic curvature angle and mobility, the biacromial and interscapular distances, the glenohumeral range of motion and the tennis serve performance were assessed three times, i.e., before and after the regular training and after the 8-week multimodal program. Results: The results showed that the 8-week regular training had no significant effects on thoracic curvature angle [effect size (ES) = 0.02-0.36, p = 0.06-0.46] and mobility (ES = 0.05-0.26, p = 0.13-0.42), biacromial (ES = 0.05, p = 0.18) and interscapular distances (ES = 0.03, p = 0.45), ranges of motion in glenohumeral internal (ES = 0.04, p = 0.43) and external rotation (ES = 0.43, p = 0.06), and tennis serve accuracy (ES = 0.33, p = 0.07) and velocity (ES = 0.09, p = 0.35). The 8-week multimodal program increased moderately the thoracic mobility (ES = 0.55, p = 0.01), moderately to strongly the serve accuracy and velocity (ES = 0.65, p = 0.003, for both), strongly decreased the interscapular distance (ES = 1.02, p < 0.001), and strongly increased the range of motion in glenohumeral internal (ES = 0.90, p < 0.001) and external rotation (ES = 1.49, p < 0.001). Discussion: These findings indicated that an 8-week multimodal program, including spine and glenohumeral mobility and shoulder girdle strength exercises, performed four times per week during 8 weeks, is moderately relevant to rectify the sagittal thoracic curvature in competitive tennis players, while such a program may help regain the range of motion in glenohumeral rotation without tennis serve performance impairment.

Opposition Skill Efficiency During Professional Rugby Union Official Games Is Related to Horizontal Force-Production Capacities in Sprinting.

PURPOSE: This study aimed to determine relationships between parameters of force-production capacity in sprinting and opposition skill efficiency in rugby union games according to position. METHODS: The sprint force-velocity profile of 33 professional rugby union players divided into 2 subgroups (forwards and backs) was measured on a 30-m sprint. Skill efficiencies (in percentage) of offensive duels, tackles, and rucks were assessed using objective criteria during 12 consecutive competitive games. Pearson correlation was used to determine the relationships between parameters of horizontal force-production capacity in sprinting (maximum propulsive power, theoretical maximum force [F0], theoretical maximum velocity, maximum ratio of horizontal force [RFmax], and rate of decrease of this ratio of forces with increasing velocity) and skill efficiencies. Two multiple linear regression models were used to observe whether skill efficiencies could depend on determinants of horizontal force application in low- or high-velocity conditions. A first model including F0 and theoretical maximum velocity was used as a macroscopic analysis, while a second model including RFmax and rate of decrease of this ratio of forces with increasing velocity was used as microscopic analysis to determine the most significant determinants of skill efficiency. RESULTS: All skill efficiencies were strongly correlated with maximum propulsive power in forwards and backs. In forwards, F0 and RFmax were the key predictors of dueling, rucking, and tackling efficiency. In backs, F0 was the main predictor of dueling and rucking efficiency, whereas RFmax was the key predictor of dueling and tackling efficiency. F0 and theoretical maximum velocity equivalently contributed to tackling performance. CONCLUSIONS: In rugby union forward and back players, skill efficiency is correlated with maximum propulsive power and may be more explained by horizontal force-production capacity and mechanical effectiveness at lower velocities than at higher velocities.

Functional Deficits After Open Latarjet Procedure and Dominance of the Operated Shoulder: An Analysis of 133 Patients.

BACKGROUND: Return to sport after stabilization surgery using the open Latarjet procedure remains challenging. Additional knowledge is needed about postoperative shoulder functional deficits in order to better design return-to-sport programs. PURPOSE: To investigate the effects of the dominance status of the operated shoulder on the shoulder functional profile recovery at 4.5 months after open Latarjet procedure. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A retrospective analysis of prospectively collected data was performed. All patients who underwent the open Latarjet procedure between December 2017 and February 2021 were eligible for the study. Functional assessment at 4.5 months after the surgery was performed using the following tests: maximal voluntary isometric contractions in glenohumeral internal and external rotation, upper-quarter Y balance test, unilateral seated shot-put test, and modified closed kinetic chain upper extremity stability test, leading to 10 outcome measures. Patients whose dominant side had undergone surgery and those whose nondominant side had undergone surgery were compared with a group of 68 healthy control participants. RESULTS: A total of 72 patients who underwent an open Latarjet procedure on the dominant side and 61 patients who underwent open Latarjet on the nondominant side were compared with 68 healthy control athletes. In patients whose dominant shoulder had undergone surgery, significant deficits for the dominant side (P < .001) and for the nondominant side (P < .001) were found in 9 of 10 functional outcome measures. Among patients whose operations were on the nondominant shoulder, significant deficits for the nondominant side (P < .001) and for the dominant side (P < .001) were found in 9 and 5 of the 10 functional outcome measures, respectively. CONCLUSION: Regardless of dominance of the stabilized shoulder, persistent deficits in strength, stability, mobility, power, and stroke frequency were observed at 4.5 months postoperatively. Stabilization of the dominant shoulder resulted in residual surgery-related functional impairments on both sides. However, stabilization of the nondominant shoulder resulted in impairments primarily noted in the nondominant, operative shoulder. REGISTRATION: NCT05150379 (ClinicalTrials.gov identifier).

Factors affecting the shoulder functional profile in elite judo athletes.

The aim was to investigate the effects of sex, age, preferred judo technique, dominance, and injury history on the shoulder functional status of elite judo athletes. Sixty-one elite judo athletes (38 males, age: 18.1 ± 1.2 years, body mass: 69.3 ± 13.3 kg, body height: 172.2 ± 9.8 cm, brown belt to second-degree black belt) completed three questionnaires: Western Ontario Shoulder Instability, Western Ontario Rotator Cuff, and Shoulder Instability-Return to Sport after Injury. They performed four physical tests: the glenohumeral rotator isometric strength test, upper quarter Y-balance test, unilateral seated shot put test, and modified Closed Kinetic Chain Upper Extremity Stability Test. The results showed that the female athletes had less shoulder functional abilities than the male athletes (p < 0.001 to p = 0.02). The younger athletes had poorer shoulder stability and upper extremity power than the older athletes (p < 0.001 to p = 0.02), but their glenohumeral muscles were stronger in both internal (p = 0.03) and external (p = 0.005) rotations. All the judo athletes had similar bilateral differences in shoulder functional status, except for judokas who preferred throwing techniques (p = 0.01). Injury history affected self-perceived functional status (p < 0.001), as well as upper extremity muscle capacity and neuromuscular control (p = 0.01 to p = 0.05). This study provides new insight into the shoulder functional status of elite judo athletes, which may aid in the development of sports-specific injury prevention and return-to-sport programmes to reduce the risk of shoulder injury occurrence and recurrence.HighlightsNormalized levels of upper extremity abilities must be sex- and age-specific in prevention programmes.Prevention programmes may focus on muscle bilateral and anteroposterior symmetry.Prevention programmes may include psychological training tailored to the sex of judo athletes.

Influence of Repeated-Sprint Ability on the in-Game Activity Profiles of Semiprofessional Rugby Union Players According to Position.

This study investigated the influence of repeated-sprint ability (RSA) on the activity of rugby union players in a competitive situation according to their position. Thirty-three semiprofessional rugby union players (age, 25.6 ± 4.3; height, 184.0 ± 8.0 cm; weight, 98.9 ± 13.9 kg, ~20 h training a week), divided into two position subgroups (forwards n = 20, backs n = 13) or four positional subgroups (front row and locks n = 13, back row n = 7, inside backs n = 6, outside backs n = 7), were tested. Their RSA was assessed with a 12 × 20 m sprint test over a 20 s cycle. GPS data (distance, acceleration, number of sprints, maximum velocity, and high-velocity running) and technical data were collected on 18 semiprofessional division rugby union games. In forwards, players with lower cumulated sprint time in the RSA test produced significantly more accelerations (ρ = -0.85, p < 0.001) and more combat actions per match minute (ρ = -0.69, p < 0.001). In backs, RSA was significantly correlated with high-intensity running [distance (ρ = -0.76), Vmax (ρ = -0.84), sprints frequency (ρ = -0.71), high-velocity running (ρ = -0.76), all p < 0.01]. Then, the players were divided into four subgroups (front row and locks, back row, inside backs and outside backs). RSA was significantly associated with the number of accelerations (ρ = -0.96, p <001) and combat actions in front row and locks (ρ = -0.71, p = 0.007). In the back row, RSA was correlated with distance (ρ = -0.96, p = 0.003) and the frequency of combat actions (ρ = -0.79, p = 0.04). In inside backs, RSA was significantly (all p < 0.01) correlated with distance (ρ = -0.81), number of accelerations (ρ = -0.94) and high-velocity running (ρ = -0.94), while in outside backs, RSA was associated with sprint frequency (ρ = -0.85) and the maximal in-game velocity reached (ρ = -0.89). These results demonstrate that RSA is associated with match running and combat activity performance (i) regardless of the position on the pitch and (ii) specifically for each player's position by improving the corresponding activity profile.

Impact of the Menstrual Cycle Phases on the Movement Patterns of Sub-Elite Women Soccer Players during Competitive Matches.

The purpose of this study was to evaluate the influence of the menstrual cycle phases on the movement patterns of sub-elite women soccer players during competitive matches over three consecutive seasons. Individual movement data were analyzed and compared in eight players from the second French League at the early follicular (EF), late follicular (LF) and mid-luteal (ML) phases of their menstrual cycle, determined by the calendar method. The movement patterns, expressed as meters per minute, were recorded during competitive matches using devices placed on the player's ankle. Our results showed significantly lower distances covered at moderate and high velocity in the EF phase than in the LF and ML phases (Cohen's d effect size = 1.03 and 0.79, respectively). The total distance covered during matches and the number of sprints also were reduced during EF compared with LF (d = 0.78 and 0.7, respectively). Overall, the total distance and distance covered at low velocity were significantly lower during the second half-time of the matches (d = 1.51), but no menstrual cycle phase × game period interaction was noted. In conclusion, our study suggests that EF may impact the movement pattern of sub-elite women soccer players during competitive matches, without any modulation of this effect by the playing time. Despite the low sample size, these results can be useful for coaches and support staff to modulate training loads and player rotation during soccer games.

The S-STARTS Test: Validation of a Composite Test for the Assessment of Readiness to Return to Sport After Shoulder Stabilization Surgery.

BACKGROUND: The time elapsed since surgery is the primary criterion for allowing athletes to return to sport after shoulder stabilization surgery using the Latarjet procedure. The objective assessment of shoulder functional status through the return-to-sport continuum demands a scoring instrument that includes psychological and physical dimensions. This study aimed to statistically validate the Shoulder-SanTy Athletic Return To Sport (S-STARTS) score in patients who have undergone primary shoulder stabilization surgery. HYPOTHESIS: The S-STARTS score fulfils the criteria for statistical validation for assessing return-to-sport readiness after shoulder stabilization surgery. STUDY DESIGN: Diagnostic study. LEVEL OF EVIDENCE: Level 4. METHODS: Fifty patients and 50 controls completed the Shoulder Instability-Return to Sport after Injury questionnaire and performed 4 physical performance tests, from which 8 outcome measures were extracted to provide a composite score, named S-STARTS, according to a scoring procedure. The statistical validation of the S-STARTS score was based on construct validity, discriminant validity, sensitivity to change, internal consistency, reliability, agreement, and feasibility. RESULTS: The 8 components of the S-STARTS score provided additional information (0.01 ≤ |r| ≤ 0.59). The S-STARTS score exhibited good reliability (intraclass coefficient of correlation [3,k] = 0.74), no ceiling or floor effects, and high discrimination and sensitivity to change. The S-STARTS score was significantly lower in patients than in controls (13.5 ± 3.8 points vs 16.1 ± 2.7 points, respectively; P < 0.001). A significant increase was reported between 4.5 and 6.5 months postoperatively (12.8 ± 2.3 points vs 17.2 ± 2.4 points, respectively; P < 0.001). CONCLUSIONS: The S-STARTS score meets statistical validation criteria for the assessment of shoulder functional status after shoulder stabilization surgery using the Latarjet procedure. CLINICAL RELEVANCE: Using an S-STARTS score-based assessment to monitor an athlete's progression through the return-to-sport continuum may help clinicians and strength and conditioning coaches in return-to-sport decision-making.

Isokinetic Strength After ACL Reconstruction: Influence of Concomitant Anterolateral Ligament Reconstruction.

BACKGROUND: To reduce the rate of anterior cruciate ligament (ACL) graft rupture, recent surgeries have involved anterolateral ligament reconstruction (ALLR). This reconstruction procedure harvests more knee flexor muscle tendons than isolated ACL reconstruction (ACLR), but its influence on knee muscle strength recovery remains unknown. This study aimed to assess the influence of ALLR with a gracilis graft on the strength of the knee extensor and flexor muscles at 6 months postoperatively. HYPOTHESIS: The additional amount of knee flexor harvest for ALLR would result in impairment in knee flexor muscle strength at 6 months postoperatively. STUDY DESIGN: Retrospective cohort study. LEVEL OF EVIDENCE: Level 2. METHODS: A total of 186 patients were assigned to 2 groups according to the type of surgery: ACL + ALLR (graft: semitendinosus + gracilis, n = 119) or isolated ACLR (graft: semitendinosus, n = 67). The strength of the knee extensor and flexor muscles was assessed using an isokinetic dynamometer at 90, 180, and 240 deg/s for concentric and 30 deg/s for eccentric contractions and compared between groups using analysis of variance statistical parametric mapping. RESULTS: Regardless of the surgery and the muscle, the injured leg produced significantly less strength than the uninjured leg throughout knee flexion and extension from 30° to 90° for each angular velocity (30, 90, 180, and 240 deg/s). However, the knee muscle strength was similar between the ACL + ALLR and ACLR groups. CONCLUSION: The addition of ALLR using the gracilis tendon during ACLR does not alter the muscle recovery observed at 6 months postoperatively. CLINICAL RELEVANCE: Although more knee flexor muscle tendons were harvested in ACL + ALLR, the postoperative strength recovery was similar to that of isolated ACLR.

Intra- and intersession reliability and agreement of the Unilateral Seated Shot-Put Test outcome measures in healthy male athletes.

BACKGROUND: The Unilateral Seated Shot-Put Test (USSPT) consists of pushing an overweight ball as far as possible to assess upper extremity power unilaterally and bilateral symmetry. Literature however reports various body positions and upper limb pushing patterns to perform USSPT, demanding to provide additional guideline to achieve overweight ball push. This study therefore aimed at assessing the reliability and agreement of USSPT outcome measures when pushing an overweight ball in a horizontal direction. METHODS: Twenty-seven healthy male athletes performed two sessions, one week apart, of three unilateral pushes per upper limb using a 3-kg medicine ball, for which the distances were measured. The intraclass correlation coefficient (ICC), standard error of measurement (SEM), minimum detectable change at a 95 % confidence level (MDC95 %) and coefficient of variation (CV) were assessed for the pushing distances based on one, two or three trials per side to produce two outcome measures: the pushing distance per limb and USSPT Limb Symmetry Index (LSI) when dividing pushing distance of the dominant side by that of the non-dominant side. RESULTS: The most reliable pushing distance per limb was obtained when averaging three pushing distances, normalized by body mass with the exponent 0.35. The mean USSPT LSI was 1.09 ± 0.10 for the first session and 1.08 ± 0.10 for the second session, highlighting good reliability and agreement (ICC = 0.82; SEM = 0.045; MDC95 % = 0.124; CV = 5.02 %). CONCLUSIONS: When the overweight ball is pushed in a horizontal direction, averaging the distances of three trials for both the dominant and non-dominant limbs is advised to provide the most reliable USSPT distance per limb and USSPT LSI.

Return to Sport Composite Test After Anterior Cruciate Ligament Reconstruction (K-STARTS): Factors Affecting Return to Sport Test Score in a Retrospective Analysis of 676 Patients.

BACKGROUND: Return to sport (RTS) to the preinjury level is the main purpose after anterior cruciate ligament (ACL) reconstruction but the factors affecting the RTS are not completely known. Knee Santy Athletic Return to Sport (K-STARTS) is a composite test designed to assess readiness for RTS after ACL reconstruction. PURPOSE: To determine the key factors that influence K-STARTS scores in a large cohort of patients after ACL reconstruction. STUDY DESIGN: Case-control study. LEVEL OF EVIDENCE: Level 3. METHODS: A retrospective analysis of prospectively collected data was undertaken. All patients who underwent ACL reconstruction surgery between March 2016 and May 2017 and also had a K-STARTS assessment at 6 months postoperatively were included. To identify factors influencing the K-STARTS score, an analysis of variance was performed. Age, sex, sports level, delay between injury and surgery, concomitant lesions, graft type, additional lateral tenodesis procedure, and participation in the RTS program were analyzed to identify factors influencing the K-STARTS score. RESULTS: A total of 676 patients were included in the study. The K-STARTS score was significantly higher in male patients than in female patients (13.9 vs 12.4; P < 0.001), in younger patients (those aged <30 years vs older patients; 14.2 vs 12; P < 0.001), ACL reconstructions performed with hamstring tendon autografts compared with bone-patellar tendon-bone (13.5 vs 13.1; P = 0.03) and in those who completed a specific RTS program in addition to standard rehabilitation, compared with those who did not participate (17.1 vs 13.1; P < 0.001). However, the only factor that significantly influenced the K-STARTS score beyond the minimal detectable change threshold was the completion of the additional RTS program. The preinjury frequency of sports participation, whether the dominant limb was injured, time from injury to surgery, the presence of associated meniscal injuries, and whether a lateral tenodesis was performed did not significantly influence the K-STARTS score. CONCLUSION: Completion of a specific RTS program, in addition to standard rehabilitation, was the most important factor influencing the K-STARTS composite functional and psychological RTS test score at 6 months after ACL reconstruction. CLINICAL RELEVANCE: This study shows that the completion of a specific RTS program affects positively the RTS test score at 6 months after ACL reconstruction.

Alterations in scapulothoracic and humerothoracic kinematics during the tennis serve in adolescent players with a history of shoulder problems.

The tennis serve generates high musculoskeletal loads at the shoulder complex, making athletes particularly vulnerable to chronic injuries, especially adolescent players. Chronic injuries are commonly related to altered scapular kinematics. This study explored the effects of a history of shoulder problems involving humerothoracic and scapulothoracic kinematics during the tennis serve at low speed in adolescent competitive players with and without a history of dominant shoulder problems. Totally, 28 adolescent tennis players were split into two groups, those with and those without a history of shoulder problems. Data on humeral and scapular kinematics relative to the thorax were collected using an electromagnetic system during slow velocity serves. The two groups's humerothoracic and scapulothoracic 3D joint angles were compared both at the end of the cocking phase and at the end of the acceleration phase of the tennis serve. At the end of the cocking phase, the players with a 30 history of shoulder problems showed less humeral abduction and external rotation and more scapular upward rotation. This group also showed less humeral abduction at the end of the acceleration phase. Players with a history of shoulder problems adapted their humerothoracic and scapulothoracic orientations to preserve shoulder integrity during the tennis serve.

Shoulder functional status in rugby union players with and without history of shoulder problems.

OBJECTIVES: To assess the effects of (1) rugby union practice, (2) history of injury managed nonoperatively, and (3) history of injury managed operatively on shoulder functional status in male rugby union players. DESIGN: Cross sectional study. SETTING: Clinical. PARTICIPANTS: 86 male athletes were assigned into four groups: multisport athletes, rugby union players without shoulder problems, with history of shoulder injury managed nonoperatively and with history of shoulder injury managed operatively. MAIN OUTCOME MEASURES: SI-RSI questionnaire, maximal isometric glenohumeral internal and external rotator strength, unilateral seated shot put test, upper quarter Y balance test. RESULTS: Healthy players presented higher internal (p = 0.03) and external (p = 0.04) rotator strength than multisport athletes. History of shoulder injury managed nonoperatively did not impair physical abilities but limited player's psychological readiness (p < 0.001). After 4.5-months, shoulder stabilization surgery impaired maximal muscle strength and upper quarter body stability and mobility (p < 0.001 for all). CONCLUSIONS: The shoulder functional status in rugby union player presented increased glenohumeral rotator strength when compared to non-collision sport athletes. In rugby union players, psychological concerns remained in the long-term after a shoulder injury managed nonoperatively, and psychological and physical readiness seemed not be reached at 4.5 months postoperatively to respond to rugby union practice demand.

Kinematic differences in upper limb joints between flat and topspin forehand drives in competitive male tennis players.

The topspin tennis forehand drive has become a feature of modern game; yet, as compared to the serve, there has been little research analysing its kinematics. This is surprising given that there is considerably more variation in the execution of the topspin forehand. Our study is the first to examine the amplitude of upper limb joint rotations that produce topspin in the forehand drives of 14 male competitive tennis players using video-based motion analysis. Humerothoracic abduction (-)/adduction (+), extension (-) /flexion (+), and external (-)/internal (+) rotation, elbow extension (-) /flexion (+) and forearm supination (-)/pronation (+), wrist extension (-)/flexion (+) and ulnar (-)/radial (-) deviation were computed. Our findings revealed that the generation of topspin demanded more humeral extension and forearm pronation but less humeral internal rotation angular displacement during the forwardswing. The follow-through phase of the topspin shot was characterised by greater humeral internal rotation and forearm pronation, and reduced humeral horizontal adduction when compared to the flat shot. This study provides practitioners with a better understanding of the upper limb kinematics associated with the topspin tennis forehand drive production to help guide skill acquisition interventions and physical training.

DOES THE GRAFT USED FOR ACL RECONSTRUCTION AFFECT THE KNEE MUSCULAR STRENGTH RATIO AT SIX MONTHS POSTOPERATIVELY?

BACKGROUND: Restoring knee muscle strength after an anterior cruciate ligament (ACL) reconstruction remains challenging. Improvement of rehabilitation program specificity demands additional knowledge on knee muscle strength deficits associated with the graft used for ACL reconstruction. PURPOSE: This study aimed to investigate the effects of graft used for ACL reconstruction on the knee muscle strength and balance assessed at six months postoperatively, based on comparisons of the isokinetic strength curves measured throughout knee extension. STUDY DESIGN: Cross-sectional study. METHODS: One-hundred-and-forty-four patients were assigned into three groups according to the graft used for a primary ACL reconstruction: semitendinosus (n=47), semitendinosus+gracilis (n = 75) and patellar (n=22) tendon graft. Normalized hamstring eccentric and quadriceps concentric torques, and hamstrings-to-quadriceps torque ratio (defined as the dynamic functional ratio) were bilaterally assessed during knee extension. Statistical parametric mapping was used to compare the curves of torques and ratio from 90 ° to 30 °of knee flexion between groups. RESULTS: The uninvolved knees presented similar strength and ratio curves in the three groups. When compared involved to uninvolved knees, hamstring strength deficit was found in hamstring tendon groups throughout knee extension (p<0.001), and quadriceps strength deficit in the three groups throughout knee extension (p<0.001). Hamstrings-to-quadriceps torque ratio was unaltered when using hamstring tendon grafts, while increased ratio was observed up to knee mid-extension when using patellar tendon graft (p<0.001). CONCLUSIONS: These findings suggest exercises with specific range of motion and contraction type in relation to graft may be considered for implementation into postoperative rehabilitation program in order to eliminate the regional strength deficits observed after ACL reconstruction. LEVEL OF EVIDENCE: 3.

Lower Trapezius Weakness and Shoulder Complex Biomechanics during the Tennis Serve.

PURPOSE: This study aimed to assess the effect of lower trapezius (LT) weakness on humeral and scapular kinematics and shoulder muscle activity during the tennis serve. METHODS: Fifteen competitive male tennis players (age, 23.8 ± 3.4 yr; height, 182.8 ± 6.7 cm; mass: 76.6 ± 8.7 kg; tennis experience: 15.6 ± 4.9 yr) performed two tennis serves before and after selective fatigue of the LT (25-min electric muscle stimulation). During each tennis serve, racket, humeral and scapular kinematics and the activity of 13 shoulder muscles were recorded using an optoelectronic system synchronized with indwelling and surface electromyography. The serve was split into five phases, that is, early and late cocking, acceleration, early and late follow-through. RESULTS: Selective fatigue led to a 22.5% ± 10.4% strength decrease but did not alter maximum racket speed and humerothoracic joint kinematics. However, increased scapular upward rotation was observed in the acceleration (P = 0.02) and early follow-through (P = 0.01) phases. Decreased muscular activity was observed during the early cocking phase for the LT (P = 0.01), during the acceleration phase for the LT (P = 0.01), anterior deltoid (P = 0.03), pectoralis major (P = 0.04), and subscapularis (P = 0.03), and during the early follow-through phase for the anterior deltoid (P = 0.03) and LT (P = 0.04). CONCLUSIONS: The LT weakness altered neither serve velocity nor humerothoracic joint kinematics, but impaired scapulothoracic kinematics and anterior shoulder muscle activation. Such alterations may reduce the subacromial space and jeopardize humeral head stability. These findings shed new light on the consequences of LT weakness, highlighting the importance of monitoring and strengthening this muscle in overhead athletes.

Intrarater reliability and agreement of a modified Closed Kinetic Chain Upper Extremity Stability Test.

OBJECTIVES: To assess the reliability of a modified procedure for Closed Kinetic Chain Upper Extremity Stability Test (CKCUEST). DESIGN: Intra- and intersession reliability and agreement; SETTING: Clinical. PARTICIPANTS: Twenty-seven asymptomatic athletes. MAIN OUTCOME MEASURES: The modifications (m-CKCUEST) in CKCUEST procedure consisted in hand spacing at one half arm-span, and to complete the three regular-series of 15 s exertion by performing a fourth 1-min series during which the number of touches was counted every 15 s. The intra- and intersession reliability and agreement were assessed for the numbers of touches in order to produce two outcome measures: m-CKCUEST score and muscular endurance index. RESULTS: The most reliable m-CKCUEST score was obtained when averaging the numbers of touches of the second and third sets (Intraclass Coefficient of Correlation(3,k); ICC = 0.92). Good reliability was found for muscular endurance index computed when dividing the one-half number of touches counted during the last 30 s of 1-min set, by the m-CKCUEST score calculated above (ICC = 0.86). CONCLUSIONS: The m-CKCUEST allowed the production of two reliable outcome measures, which assessed the upper limb stability and the muscular endurance. Such outcomes may be used in a follow-up to assess performance or rehabilitation level.

Validation of a Composite Test for Assessment of Readiness for Return to Sports After Anterior Cruciate Ligament Reconstruction: The K-STARTS Test.

BACKGROUND:: There is limited information on the appropriate timing of return to sports after anterior cruciate ligament (ACL) reconstruction. A composite test was developed to assess the athlete's ability to return to sports after ACL reconstruction: the Knee Santy Athletic Return To Sport (K-STARTS) test. HYPOTHESIS:: The K-STARTS test meets validation criteria for an outcome score assessing readiness for return to sports after ACL reconstruction. STUDY DESIGN:: Diagnostic study. LEVEL OF EVIDENCE:: Level 3. METHODS:: A prospective comparative study identified 410 participants: 371 participants who had undergone ACL reconstruction and a control group of 39 healthy participants. The K-STARTS score is calculated as the sum of 7 tests (8 components), for a maximal value of 21 points. Construct validity, internal consistency, discriminant validity, and sensitivity to change were used to validate this new test. RESULTS:: The K-STARTS assessment showed a high completion rate (100%), high reproducibility (intraclass correlation coefficient, 0.87; coefficient of variation, 7.8%), and high sensitivity to change. There was moderate correlation with the ACL Return to Sports after Injury scale (ACL-RSI) and hop tests. There were no ceiling or floor effects. There was a significant difference between K-STARTS scores assessed at 6 and 8 months postoperatively (11.2 ± 2.7 vs 17.1 ± 3.2; P < 0.001). The K-STARTS score in the control group was significantly higher than that in the ACL reconstruction group (17.3 ± 2.1 and 13.7 ± 3.8, respectively; P < 0.001). CONCLUSION:: The K-STARTS test is an objective outcome measure for functional improvement after ACL reconstruction. CLINICAL RELEVANCE:: It is important for the clinician to determine when return to sports is optimal after ACL reconstruction to reduce the current high risk of reinjury.

Shoulder range of motion and strength in young competitive tennis players with and without history of shoulder problems.

OBJECTIVE: To assess the effect of a history of shoulder problems on the shoulder flexibility and strength in young competitive tennis players. DESIGN: Cross-sectional study. PARTICIPANTS: Ninety-one competitive and asymptomatic tennis players aged between 8 and 15 years old were divided into two groups according to the presence or absence of a history of shoulder problems. OUTCOME MEASURES: Glenohumeral joint ranges of motion and the strength of eight shoulder muscles were bilaterally assessed. Five agonist/antagonist muscle strength ratios were also reported. Ranges of motion, strengths and strength ratios were bilaterally compared between the two groups. RESULTS: Players with a history of shoulder problems presented a higher total arc of rotation for both glenohumeral joints (p = 0.02) and a lower external/internal glenohumeral rotator muscle strength ratio (p = 0.02) for both sides. They also presented stronger upper trapezius (p = 0.03) and dominant serratus anterior (p = 0.008) muscles than players without a history of shoulder problems. CONCLUSION: Having a history of shoulder problems may alter the balance between mobility and stability within the shoulder complex suggesting that particular attention should be given to dominant and non-dominant shoulder functions by coaches and clinicians.