The HAR-index: a reliable method for evaluating the risk of total hip arthroplasty conversion after hip arthroscopy for femoroacetabular impingement.

PURPOSE: Hip arthroscopy is a growing technique in the treatment of femoroacetabular impingement (FAI), but can sometimes lead to unsatisfactory results such as the early conversion to total hip arthroplasty (THA). The purpose of this study is to describe a new tool for assessing the preoperative risk of THA conversion after hip arthroscopy in patients with FAI. METHODS: This study is a retrospective analysis of a prospective cohort of 584 patients with FAI who underwent hip arthroscopy at a single centre with a minimum 2 years follow-up. The preoperative variables of these patients were analysed to calculate the risk of each variable for THA. By selecting variables with an area under the receiver operating characteristic (ROC) curve greater than 0.7, a calculator was created to provide a risk index for each patient. RESULTS: Four variables (age, body mass index, Tönnis score and ALAD) were associated with an increased risk of THA conversion. The optimal cut-off points for each variable were determined, and a risk index was created. The Hip-Arthroplasty-Risk Index (HAR-Index) is a 0-4 points scale obtained from four binary scores of 0 or 1 depending on whether the cut-off point for each variable was reached or not. The increased risk of THA for each HAR-Index value was 1.1%, 6.2%, 17.9%, 55.1% and 79.3% respectively. The HAR-Index showed a very good predictive capacity with an area under the ROC curve of 0.89. CONCLUSION: The HAR-Index is a simple and practical tool for practitioners to make more informed decisions about performing hip arthroscopy in patients with FAI. With a very good predictive capacity, the HAR-Index can help to reduce the rate of conversion to THA. LEVEL OF EVIDENCE: Level III.

Hip arthroscopy is a successful treatment for femoroacetabular impingement in under-16 competitive football players: a prospective study with minimum 2-year follow-up.

INTRODUCTION: Femoroacetabular impingement is considered a spectrum disease affecting multiple hip structures and it is especially prevalent in football players. Hip arthroscopy has shown good results in this population. However, little attention has been given to its efficacy in children and adolescent players. The aim of this study is to evaluate the outcomes of hip arthroscopy in under-16 football players. MATERIALS AND METHODS: Between 2008 and 2019, all under-16 competitive football players who underwent hip arthroscopy for the treatment of femoroacetabular impingement were recruited for this prospective study. Hip pain and function were measured through the VAS, HOS, mHHS and WOMAC scores before the surgery, at 1-year after the surgery and at minimum 2-years after surgery. Preoperative and postoperative scores were compared to  establish the evolution of hip pain and function. Additionally, rate and time to return to play were recorded. RESULTS: 14 subjects were included in the analysis. All subjects attended to the last follow-up, at mean 3.21 years after the surgery (range 2-10). Mean ± SD VAS (0-100) scores were 60.14 ± 15.88 before the surgery, 6.43 ± 5.19 at 1-year follow-up and 5.07 ± 4.05 at final follow-up (p < 0.05). Significant improvements were observed in HOS ADL, HOS SS, mHHS and WOMAC (p < 0.05) between preoperative values and 1-year follow-up. No significant differences were found in knee pain or function between 1-year and final follow-up assessments (p > 0.05). All subjects (100%) were playing football 1-year after the surgery, with a mean ± SD time to return to play of 5.93 ± 2.09 months. 13 subjects (92.86%) were still playing at final follow-up. CONCLUSIONS: Hip arthroscopy is a safe and effective surgical procedure for the treatment of FAI in under-16 competitive football players, improving hip pain and function with excellent rates to return to play.

Arthroscopic resection as a rapid recovery treatment for Os acetabuli in soccer players who had undergone hip arthroscopy: a case series with 1-year follow-up.

INTRODUCTION: Os acetabuli (OSA) is defined as a radiopaque structure located around the acetabular rim highly related to Femoroacetabular Impingement (FAI). Its treatment depends on the perspective of post-surgical joint instability. Ossicle resection is recommended if the femoral head is covered enough by the labrum. Previous research has described the results of this technique in general population. The aim of this study is to describe the outcomes and the time and rate of return to play (RTP) after hip arthroscopy and OSA removal in soccer players. METHODS: This study is a retrospective analysis of a prospective database containing all the consecutive soccer players who had undergone hip arthroscopy between 2018 and 2019. The subjects diagnosed with OSA and a center-edge angle (CEA) > 25 ° were included in the analysis. All the patients were treated with arthroscopic removal of the OSA and femoral osteoplasty. Hip function was assessed using the Modified Harris Hip Score (MHHS) before and at 3 and 12 months after surgery. Rate of RTP and competitive level at RTP were assessed at a 1-year follow-up. RESULTS: Between 2018 and 2019, 90 soccer players were treated with hip arthroscopy in our facilities. Six of them (6.6%) were diagnosed with OSA. Mean (SD) MHHS values were 69.7 (12.1) before the surgery, 89.7 (6.7) at 3 months post-surgery and 95.7 (5.1) at 12 months post-surgery. All the subjects reported significant improvements in their MHHS scores at 3 and 12 months post-surgery compared with pre-surgery levels (p < 0.01). Non-significant differences were found between 3 and 12 months post-surgery (p > 0.05). All the subjects (100%) returned to previous competitive levels. CONCLUSIONS: After surgery, all the soccer players returned to previous competitive level. Preoperative MHHS improved significantly at 3 months maintained for up to 12 months.

The natural history of alpha angle in the last seventeen centuries.

INTRODUCTION: Hip osteoarthritis is one of the most important and debilitating diseases affecting thousands of people all over the world. On the other hand, femoroacetabular impingement (FAI) is one of the known important causes of hip osteoarthritis. Cam deformity frequently presents in FAI showing an increased alpha angle. Increased alpha angle has been observed among young patients involved in demanding physical activities such as in sports (40-60%), whereas among the non-athletic population, increased alpha angle was observed in 15-20%. Although femoroacetabular pathology has been described over the recent years, it is not possible to determine when the angle increase actually begins prior to diagnosis. The aim of our study is to evaluate the femoral alpha angle in different human femurs in different civilization eras in West Mediterranean area. MATERIALS AND METHODS: Available ancient femurs were selected from the Collection Center belonging to the archeological archives (ancient necropolis) from the fourth, fourteenth and eighteenth centuries. A comparison of the alpha angle was made of the measurements from the different groups accompanied by a sample of present-day femurs from the radiology database of CT scans. Data from 243 femoral bones were collected, 50 of which from the fourth century, 26 from the fourteenth century, 68 from the eighteenth century, and 99 femurs from the 20/twenty-first century. RESULTS: Alpha angles in all historical samples showed pathological values (> 55º) up to a maximum of 11.5% of the cases. Meanwhile, the actual series showed pathological alpha angle in 60.1% of the cases with statistical significant differences. CONCLUSION: The studied femurs of the western Mediterranean region from the fourth, fourteenth and eighteenth centuries showed pathological alpha angles in a smaller proportion than the actual sample. LEVEL OF EVIDENCE: Level III, retrospective studies.

Preoperative risk factors in hip arthroscopy.

PURPOSE: Arthroscopic surgery is a usual technique to repair hip femoroacetabular impingement. Correlation exists among surgical indication, postoperative evolution, the final result, and the necessity of prosthesis in the near future. The assessment of specific parameters allowing us to evaluate the prognosis becomes vital to improve the results. The objective of this study is to check the variables found in patients with femoroacetabular impingement (FAI) treated with hip arthroscopy, and determine which of these variables would serve as key indicators in predicting the need for subsequent arthroplasty. METHODS: Data from FAI surgical indications (age, weight, height, BMI, gender, side, radiographic Tönnis degree, cartilage lesion degree by Acetabular Labrum Articular Disruption (ALAD) degree, VAS value, HOS, mHHS and WOMAC) were collected from cases which should have had a minimum monitoring period of 2 years from 2007 to 2017. The results of the group which needed prosthesis were compared to the results of the ones who did not. RESULTS: Among 452 patients who were monitored for an average of 5.8 years, 82 (18.1%) required conversion to prosthesis. The variables that indicated relatively high risk were fourth-degree acetabular labrum articular disruption (ALAD) chondral injury, preoperative radiographic Grade 2 Tönnis classification, age of over 55 years, WOMAC over 45 points, and HOS-ADL under 50 points. There were no significant differences between side, gender, VAS level, nor HOS. CONCLUSIONS: The presence of chondral injuries such as acetabular labrum articular disruption (ALAD) 4, radiographic Grade 2 Tönnis classification, higher age, higher BMI, and worse WOMAC, along with mHHS and HOS-ADL preoperative results, are factors which lead to a poor prognosis following FAI hip arthroscopic surgery, increasing the risk of prosthetic conversion in the short or medium term. LEVEL OF EVIDENCE: Level IV.

Platelet-Rich Plasma Applications for Achilles Tendon Repair: A Bridge between Biology and Surgery.

Achilles tendon ruptures are very common tendon ruptures and their incidence is increasing in modern society, resulting in work incapacity and months off sport, which generate a need for accelerated and successful therapeutic repair strategy. Platelet-rich plasma (PRP) is emerging as adjuvant human blood-derived constructs to assist Achilles tendon rupture treatment. However, myriad PRP preparation methods in conjunction with poor standardization in the modalities of their applications impinge on the consistent effectiveness of clinical and structural outcomes regarding their therapeutic efficacy. The purpose of this review is to provide some light on the application of PRP for Achilles tendon ruptures. PRP has many characteristics that make it an attractive treatment. Elements such as the inclusion of leukocytes and erythrocytes within PRP, the absence of activation and activation ex vivo or in vivo, the modality of application, and the adjustment of PRP pH can influence the biology of the applied product and result in misleading therapeutic conclusions. The weakest points in demonstrating their consistent effectiveness are primarily the result of myriad PRP preparation methods and the poor standardization of modalities for their application. Selecting the right biological scaffold and applying it correctly to restitutio ad integrum of ruptured Achilles tendons remains a daunting and complex task.

The presence of patellar tendinopathy in the bone-patellar tendon-bone autograft may increase the risk of anterior cruciate ligament graft failure.

PURPOSE: The purpose of this study was to evaluate the influence of patellar tendinopathy on primary anterior cruciate ligament (ACL) reconstruction graft failure when using bone-patellar tendon-bone (BPTB) autograft. METHODS: All patients undergoing primary ACL reconstruction using ipsilateral BPTB with preoperative magnetic resonance imaging (MRI) available for review were approached for eligibility. The medical charts of included patients were reviewed to obtain demographic information, anatomical characteristics, injury characteristics, treatment characteristics, length of follow-up, and presence of graft failure. A single, fellowship-trained, knee-specialist and blinded researcher performed preoperative MRI interpretation of patellar tendinopathy. The presence/absence of patellar tendinopathy (none, mild, moderate, or severe changes) was compared between patients with (cases) and without (controls) failure of ACL reconstruction. There were 559 cases with a median (range) clinical follow-up was 8 (4-30) months and an average age of 21.5 years (82% males). RESULTS: Of the 559 cases, there were 182 (32.6%) with and 377 (67.4%) without patellar tendinopathy. A total of 32 (5.7%) graft failures occurred. There were a significantly higher failure rate in patients with compared to without patellar tendinopathy (p < 0.001), and in patients with compared to without partial tendon tear (p < 0.001). The odds ratio (95% confidence interval) for graft failure was 5.9 (2.7-13.1), 20.8 (6.8-63.9) and 54.4 (5.5-539.4) in patients with patellar tendinopathy (compared to absence of patellar tendinopathy), moderate or severe patellar tendinopathy (compared to none or mild patellar tendinopathy), or partial tendon tear (compared to absence of tendon tear), respectively. CONCLUSION: The presence of patellar tendinopathy increases the risk of BPTB graft failure when used for ACL reconstruction. The use of BPTB autograft is not recommended if patellar tendinopathy is obvious or there are suspicious of partial tendon tear on MRI. In such cases, the surgeon should consider using a different graft. LEVEL OF EVIDENCE: Retrospective cohort analysis, Level III.

Gluteus maximus contraction velocity assessed by tensiomyography improves following arthroscopic treatment of femoroacetabular impingement.

PURPOSE: Muscular impairment, particularly for the gluteus maximus (GM), has been observed in femoroacetabular impingement (FAI). The purpose of this study was to evaluate the tensiomyographic changes of the GM, rectus femoris (RF) and adductor longus (AL) before and after arthroscopic surgery for FAI. It was hypothesized that arthroscopic treatment of FAI would improve the preoperative muscular impairment. METHODS: All patients undergoing arthroscopic treatment of FAI between January and July 2015 were approached for eligibility. Patients included had a tensiomyography (TMG) evaluation including maximal displacement (Dm) and contraction time (Tc) of these muscles in both lower extremities. TMG values between the injured and healthy sides were compared at the preoperative and post-operative (3, 6 and 12 months after surgery) periods. RESULTS: There were no significant differences for the RF and AL, and Dm of the GM for any of the comparisons (n.s.). However, GM Tc was significantly lower at 3 (p = 0.016), 6 (p = 0.008), and 12 (p = 0.049) months after surgery in the injured side compared to preoperatively. GM Tc of the healthy side was significantly lower than the injured side at the preoperative period (p = 0.004) and at 3 (p = 0.024) and 6 (p = 0.028) months after surgery, but these significant differences were no longer observed at 12 months after surgery (n.s.). There was a significant reduction of pain in the GM area at 1 year after surgery compared to preoperatively (p < 0.0001). CONCLUSIONS: Arthroscopic treatment of FAI and the subsequent rehabilitation improves contraction velocity of the GM of the injured side. Despite Tc is elevated in the GM of the injured compared to the healthy side preoperatively and at 3 and 6 months after surgery, differences in Tc between both sides are no longer significant at 12 months. Athletes with FAI participating in sports with great involvement of GM may benefit from arthroscopic treatment and its subsequent rehabilitation. TMG can be used as an objective measurement to monitor muscular improvements of the GM after surgery in these patients. LEVEL OF EVIDENCE: II.

LISS plate for treatment of distal femur fracture. Clinical and functional outcomes.

The aim of the present study is to evaluate the use of the Less Invasive Stabilization System (LISS) plate for distal femoral fractures, examining variables such as type of fracture and length of plate. A retrospective study of 30 patients with a distal femoral fracture, treated with a distal femur LISS plate (Synthes) was performed. Average age was 71 years old (20-101). According to the AO classification, 16 fractures were type A, 5 type B, and 9 type C. The consolidation index and clinical outcomes measured with Knee Society Score (KSS) questionnaire were evaluated. Fracture consolidation took an average time of 16 weeks (14-20). Mean KSS was 77,3 (50-97) at the 2-year follow-up visit, observing better outcomes on type C fractures (84,25). According to the KSS score, only two cases were described with bad functional outcomes (6%). Distal femur fractures treated with the LISS plate achieved 94% of good and acceptable outcomes. Unlike the previously published, the best results were obtained with AO type C fractures, probably associated to the lower age (mean 53 years old) and better functional recovery capacity of this group.

Return to sports after arthroscopic capsulolabral repair using knotless suture anchors for anterior shoulder instability in soccer players: minimum 5-year follow-up study.

PURPOSE: To report the return to sports and recurrence rates in competitive soccer players after arthroscopic capsulolabral repair using knotless suture anchors at a minimum of 5 years of follow-up. METHODS: All competitive soccer players with anterior glenohumeral instability treated by arthroscopic capsulolabral repair using knotless suture anchors between 2002 and 2009 were retrospectively identified through the medical records. Inclusion criteria were: no previous surgical treatment of the involved shoulder, absence of glenoid or tuberosity fractures, absence of large Hill-Sachs or glenoid bone defect, minimum follow-up of 5 years, instability during soccer practice or games, and failure of non-surgical treatment. The charts of included players were reviewed, and a phone call was performed in a cross-sectional manner to obtain information on: current soccer, return to soccer, recurrence of instability, shoulder function (Rowe score), and disability [Quick-Disability of the Arm, Shoulder, and Hand (DASH) score and Quick-DASH Sports/Performing Arts Module]. RESULTS: Fifty-seven young male soccer players were finally included with a median (range) follow-up of 8 (5-10) years. Forty-nine (86 %) of the soccer players were able to return to soccer and 36 of them (73 %) at the same pre-injury level. There were 6 (10.5 %) re-dislocations in the 57 players, all of them of traumatic origin produced during soccer and other unrelated activities. The main reasons to not return to soccer were: knee injuries (two players), changes in personal life (two players), and job-related (three players). None of the players quit playing soccer because of their shoulder instability injury. The median (range) Rowe score, Quick-DASH score, and Quick-DASH sports score were 80 (25-100), 2.3 (0-12.5), and 0 (0-18.8), respectively. CONCLUSIONS: Competitive soccer players undergoing arthroscopic capsulolabral repair with knotless suture anchors for shoulder instability without significant bone loss demonstrate excellent return to play at mid-to-long-term follow-up, with a 10.5 % chances of re-dislocating. LEVEL OF EVIDENCE: IV.

Comparison of tensiomyographic neuromuscular characteristics between muscles of the dominant and non-dominant lower extremity in male soccer players.

PURPOSE: Tensiomyography (TMG) has been used to assess neuromuscular characteristics of muscles of the lower extremity in soccer players. However, the effects of lower extremity dominance on TMG characteristics in this population have not been reported to date. The purpose of this study was to compare the TMG neuromuscular characteristics between the dominant and non-dominant lower extremity in male soccer players. METHODS: Thirty-eight consecutive healthy male soccer players underwent resting TMG assessment of vastus medialis (VM), vastus lateralis (VL), rectus femoris (RF), semitendinosus (ST), biceps femoris (BF), gastrocnemius medialis (GM), and gastrocnemius lateralis (GL) in both lower extremities. The maximal displacement, delay time, contraction time, sustained time, and half-relaxation time were obtained and compared between both sides. RESULTS: There were no significant differences in the vast majority of the TMG parameters between both lower extremities. The dominant side demonstrated higher VM contraction time (p = 0.008), RF sustained time (p = 0.009), RF half-relaxation time (p = 0.01), and BF sustained time (p = 0.04), but lower VL contraction time (p = 0.03) and VL delay time (p = 0.02) compared to the non-dominant side. CONCLUSION: In general, TMG-assessed neuromuscular characteristics of the VM, VL, RF, ST, BF, GM, and GL were not affected by lower extremity dominance in male soccer players. Therefore, there is no need to assess both sides when using TMG to monitor the response to training or muscles at risk of injury in soccer players unless there is a specific reason. LEVEL OF EVIDENCE: Prognostic study, Level II.

Pain in donor site after BTB-ACL reconstruction with PRGF: a randomized trial.

INTRODUCTION: Anterior cruciate ligament (ACL) tears are highly incident injuries in young athletes within our work area. The use of the patellar graft, despite being the treatment of choice, presents post-operative problems such as anterior knee pain, which limits its use and leads to preference being taken for alternative grafts. Our aim was to evaluate if the application of PRGF reduces anterior knee pain in donor site in BTB-ACL reconstruction. MATERIALS AND METHODS: 43 patients were included in the double-blinded and randomized clinical trial comparing two patient groups who underwent ACL reconstruction using patellar tendon graft, comparing anterior knee pain with and without the application of PRGF at the donor site after harvesting the graft. RESULTS: The PRGF group showed decreased donor site pain in comparison to the control group, with significant differences in the first two months of follow-up. CONCLUSION: The application of PRGF decreased donor site pain compared to the control group.

Return to prelesional Tegner level after anatomic anterior cruciate ligament reconstruction.

INTRODUCTION: Injury and surgery of the anterior cruciate ligament (ACL) are very frequent within the sports environment. The purpose of the present study is to assess the level at which a group of athletes were able to return to play (RTP) after ACL reconstruction, and most importantly, the time for RTP. MATERIALS AND METHODS: A prospective study with patients who presented an ACL injury and underwent ligament reconstruction surgery; a bone-tendon-bone reconstruction and a minimum follow-up of 24 months. The rates of RTP as well as correlations with IKDC and KT-1000 were collected. RESULTS: 42 patients were included (mean age 31.7 years old). Mean Tegner level was 6.7. 9.5 % of patients returned to sports 6 months after surgery, 52.3 % at 1 year, and 73.8 % at 2 years after ACL reconstruction. 11 patients did not achieve their preoperative Tegner level after 2 years of follow-up. Levels of KT-1000 of the operated side were normal, and IKDC levels reached 90 % of total. CONCLUSIONS: Fear to a new injury, psychological factors, personality, type of life, and sports level previous to the injury are factors that influence when it comes to RTP after an ACL surgery. Level of evidence Level II descriptive analysis.

Gluteus maximus impairment in femoroacetabular impingement: a tensiomyographic evaluation of a clinical fact.

INTRODUCTION: the aim of the present study is to evaluate the mechanical and contractile properties of the gluteus maximus (GM) muscle in patients with femoroacetabular impingement (FAI). Our hypothesis is that the clinical observation of GM pain would be evidenced by tensiomyographic impairment in muscle function. MATERIALS AND METHODS: A prospective, cross-sectional, intra-group comparative study was conducted to assess the neuromuscular changes of lower extremity muscles in patients with FAI. Fifty-one patients with clinical and radiographic diagnosis of FAI for at least 3 months were included. The rectus femoris (RF), adductor magnus (AM), and GM of both lower extremities of all patients were evaluated with tensiomyography (TMG). The values of TMG of the affected lower extremity were compared to those of the healthy contralateral side. The parameters obtained in this study were maximal displacement (Dm), and contraction time (Tc). RESULTS: The Tc of the injured GM was significantly higher compared to the healthy side (p = 0.01). There were no significant side-to-side differences in the Dm of the GM (p = 0.13), either in the Tc and Dm of the RF (p = 0.15 and p = 0.8, respectively) and AM (p = 0.25 and p = 0.75, respectively). CONCLUSIONS: FAI is associated with impairment of contraction time in the GM of the injured compared to the healthy side. Impairment of the GM may be monitored to evaluate response to conservative or surgical treatment.

The international Hip Outcome Tool-33 (iHOT-33): multicenter validation and translation to Spanish.

BACKGROUND: The international Hip Outcome Tool-33 (iHOT-33) is a 33-item self administered outcome measure based on a Visual Analogue Scale response format designed for young and active population with hip pathology. The aim of the present study is to translate and validate the iHOT-33 into Spanish. METHODS: 97 patients undergoing hip arthroscopy were included in this prospective and multicenter study performed between January 2012 and May 2014. Crosscultural adaptation was used to translate iHOT-33 into Spanish. Patients completed the questionnaire before and after surgery. Feasibility, reliability, internal consistency, construct validity (correlation with Western Ontario and McMaster Universities Osteoarthritis Index), ceiling and floor effects and sensitivity to change were assessed for the present study. RESULTS: Mean age was 48 years old. Feasibility: 41.2 % patients had no blank questions, and 71.3 % of patients had fulfilled all but one or two questions. Reliability: ICC for the global questionnaire was 0.97, showing that the questionnaire is highly reproducible. Internal consistency: Cronbach's alpha was 0.98 for the global questionnaire. Construct validity: there was a high correlation with WOMAC (correlation coefficient >0.5). The Ceiling effect (taking into account the minimum detectable change) was 12.1 % and the floor effect was 21.6 %, for the global questionnaire. Large sensitivity to change was shown. CONCLUSION: the Spanish version of iHOT-33 has shown to be feasible, reliable and sensible to changes for patients undergoing hip arthroscopy. This validated translation of iHOT-33 allows for comparisons between studies involving either Spanish- or English-speaking patients. LEVEL OF EVIDENCE: Prognostic study, Level I.

Biologic enhancement of cartilage repair: the role of platelet-rich plasma and other commercially available growth factors.

In part, people's quality of life depends on the "health" of their cartilage because its damage or deterioration causes pain that limits mobility and reduces autonomy. Predisposing genetic factors and modern-life environmental factors, such as diet, excessive physical exercise, or the absence of any physical exercise, in addition to injuries that can occur, all contribute to the onset and development of chronic degenerative diseases such as osteoarthritis. Regenerative medicine focuses on the repair, replacement, or regeneration of cells, tissues, or organs to restore impaired function from any cause, including congenital defects, disease, and trauma.

Healing of donor site in bone-tendon-bone ACL reconstruction accelerated with plasma rich in growth factors: a randomized clinical trial.

PURPOSE: To determine whether the use of plasma rich in growth factors accelerates healing of the donor site in bone-tendon-bone anterior cruciate ligament (ACL) reconstruction (patellar graft). The use of the patellar graft presents post-operative problems such as anterior knee pain, which limits its use and leads to preference being taken for alternative grafts. METHODS: A double-blind, randomized, clinical trial was performed comparing two groups of patients who underwent ACL reconstruction using patellar tendon graft and comparing the use of plasma rich in growth factors at the donor site after graft harvest in terms of local regeneration by ultrasound assessment. RESULTS: The plasma rich in growth factors group shows earlier donor site regeneration in comparison with the control group (2 months earlier), with significant differences in the first 4 months of the follow-up. CONCLUSION: The application of plasma rich in growth factors shows accelerated tissue regeneration processes with respect to the control group. This fact, together with the previously published with similar conclusions, can create a knowledge basis in order to set out new recovery guidelines following ACL reconstruction. LEVEL OF EVIDENCE: Therapeutic study, Level I.

Effects of anterior cruciate ligament reconstruction on neuromuscular tensiomyographic characteristics of the lower extremity in competitive male soccer players.

PURPOSE: To investigate the effects of anterior cruciate ligament (ACL) reconstruction on mechanical and contractile properties of the skeletal muscles of the lower extremities in soccer players through tensiomyography (TMG). METHODS: All soccer players with acute ACL tear included underwent resting TMG assessment of muscles of both lower extremities before and 1 year after ACL reconstruction. The muscles assessed were vastus medialis (VM), vastus laterals (VL), rectus femoris (RF), semitendinosus (ST), biceps femoris (BF), gastrocnemius medialis (GM), and gastrocnemius lateralis (GL). The TMG parameters obtained for each muscle were maximal displacement (D m), delay time (T d), contraction time (T c), sustained time (T s), and half-relaxation time (T r). RESULTS: The injured leg had a significant decrease in VL-T c, ST-T c, GM-T c, GL-T r, and GL-T d, and a significant increase in VM-T r and GM-T s in the postoperative compared to preoperative period. The non-injured leg demonstrated significant preoperative-postoperative changes in the VL, RF, and BF, but not in VM, ST, GM, and GL The magnitude of preoperative-postoperative differences in the injured leg was significantly higher in RF-T c, ST-T c, BF-D m, and GL-T r, but lower in RF-T r and GM-T s, compared to the non-injured leg. Both groups improved their symmetry between the quadriceps and hamstring muscle groups in both sides. CONCLUSIONS: The quadriceps muscles improved their resistance to fatigue and contraction velocity in both sides, and the hamstring muscles improved their contraction velocity and muscle tone in both sides as well. Improvements in contraction velocity and muscle tone were more evident in the quadriceps and hamstrings of the injured compared to the uninjured side. In addition, the intervention increased the percentage of symmetry between both sides in the TMG of the quadriceps muscles and the balance between ACL-agonist (hamstrings) and ACL-antagonist (quadriceps) muscle groups in both sides. This study shows how ACL reconstruction (and subsequent rehabilitation) can positively impact neuromuscular characteristics of the quadriceps and hamstrings. LEVEL OF EVIDENCE: Therapeutic, Level II.

Assessment of gastrocnemius tensiomyographic neuromuscular characteristics as risk factors for anterior cruciate ligament injury in male soccer players.

PURPOSE: There is a large number of publications evaluating neuromuscular risk factors for anterior cruciate ligament (ACL) injury in athletes. However, most of them have involved the female athlete and, in addition, the gastrocnemius muscles have been less investigated by far compared with the quadriceps and hamstring. The purpose of this study was to investigate the role of the gastrocnemius muscles as neuromuscular risk factors for ACL injury in male soccer players, through tensiomyography (TMG). METHODS: All competitive male soccer players with confirmed ACL tear included in this study underwent resting TMG assessment of gastrocnemius medialis (GM) and gastrocnemius lateralis muscles of the uninjured side. The same values were obtained from a sex-, and sports level-matched control group in both sides. The maximal displacement (D m), delay time (T d), contraction time (T c), sustained time (T s), and half-relaxation time (T r) were obtained for both muscles. TMG values of the uninjured side in ACL-injured group were compared with the mean values between both sides in the control subjects. RESULTS: There were no significant between-group differences in demographic characteristics. Most TMG parameters of the gastrocnemius muscles were not significantly different between the two groups. Only the GM-T r (p = 0.02) and GM-D m (p = 0.006) were significantly higher in the ACL-injured group compared with control group. CONCLUSIONS: Neuromuscular characteristics in terms of mechanical and contractile properties of the gastrocnemius muscles may not be significant risk factors for ACL injury in male soccer players.