Strength development and non-contact lower limb injury in academy footballers across age groups.

Non-contact lower limb injuries are common in academy football. Yet, the impact these injuries have on strength development in academy footballers remains unclear. This study aimed to investigate the impact of non-contact lower limb injury on hip, groin, and knee flexor strength development in male academy youth footballers. Furthermore, this study: reports normative strength data of emerging field-based tests that can be easily deployed in football academies; explores the effect of age on injury occurrence; and highlights the number of days lost from injury in male youth footballers. Assessments of hip adductor, abductor, and eccentric knee flexor strength were obtained from 195 academy football players during pre-season and at the end of season. In-season injuries were recorded by medical staff. Those footballers who sustained non-contact lower limb injury were compared with those who did not sustain a non-contact lower limb injury. No between-group differences were observed for any strength assessments when controlled for pre-season measures. Stronger footballers at pre-season experienced strength loses, while those weaker players gained strength across the season. Hip strength development was impaired in older age group footballers. Sustaining a non-contact lower limb injury had minimal impact on strength development. In the absence of in-season lower limb strength monitoring, development in academy youth footballers may not progress as expected, and in particular, stronger and older youth athletes may benefit from individualized strength training.

[Groin pain in athletes : What does the sports physician expect from the radiologist?] / Leistenschmerzen beim Sportler : Was erwartet der Sportarzt vom Radiologen?

BACKGROUND: Especially in sports like professional football (soccer) making a diagnosis and generating a final prognosis concerning the time loss is demanding for the team physician and the radiologist. Therefore, the radiologist has to fulfill the requests concerning availability and quality of imaging. This is a particularly difficult task for groin pain because it can be caused by a variety of pathologies. OBJECTIVES: In addition to the question what the sports physician expects from the radiologist, we have to look at which information the radiologist needs to answer the raised questions. Which external circumstances make a change of the normal procedures necessary when supporting athletes? RESULTS AND DISCUSSION: Close collaboration between the radiologist and sports physician guarantees that the raised questions from the athlete and the club concerning time loss and necessary therapy can be answered. Thus, the sports physician has to give the radiologist detailed information regarding symptoms, location of the pain and other clinical findings. The radiologist has to include this information into the interpretation of the images to distinguish safely between findings caused by the actual injury and those which are pre-existing.

[Stress fracture of athletes as a cause of groin pain]. / Stressfrakturen beim Sportler als Ursache von Leistenschmerzen.

CLINICAL/METHODICAL ISSUE: In this article, suitable imaging of stress reactions and stress fractures in athletes will be examined. STANDARD RADIOLOGICAL METHODS: Diagnostic procedures include X­ray, computed tomography (CT), magnetic resonance imaging (MRI), and bone scintigraphy. METHODICAL INNOVATIONS: MRI represents the gold standard for these types of injuries. PERFORMANCE: Of all imaging techniques, MRI shows the highest sensitivity in terms of diagnostic and prognostic aspects in stress reactions and stress fractures. PRACTICAL RECOMMENDATIONS: Early performance of MRI to evaluate the staging, therapy and prognosis of the healing process is recommended.

Hip Strength Testing of Soccer Players With Long-Standing Hip and Groin Pain: What are the Clinical Implications of Pain During Testing?

OBJECTIVE: To investigate whether self-reported pain during hip strength testing correlates to a large degree with hip muscle strength in soccer players with long-standing unilateral hip and groin pain. DESIGN: Cross-sectional study. SETTING: Clinical assessments at Sports Orthopaedic Research Center-Copenhagen (SORC-C), Arthroscopic Centre Amager, Copenhagen University Hospital, Denmark. PARTICIPANTS: Twenty-four male soccer players with unilateral long-standing hip and groin pain. INTERVENTIONS: The soccer players performed 5 reliable hip muscle strength tests (isometric hip flexion, adduction, abduction, isometric hip flexion-modified Thomas test, and eccentric hip adduction). MAIN OUTCOME MEASURES: Muscle strength was measured with a hand-held dynamometer, and the players rated the pain during testing on a numerical rating scale (0-10). RESULTS: In 4 tests (isometric hip adduction, abduction, flexion, and eccentric adduction), no significant correlations were found between pain during testing and hip muscle strength (Spearman rho = -0.28 to 0.06, P = 0.09-0.39). Isometric hip flexion (modified Thomas test position) showed a moderate negative correlation between pain and hip muscle strength (Spearman rho = -0.44, P = 0.016). CONCLUSIONS: Self-reported pain during testing does not seem to correlate with the majority of hip muscle strength tests used in soccer players with long-standing hip and groin pain.

Referred pain and cutaneous responses from deep tissue electrical pain stimulation in the groin.

BACKGROUND: Persistent postherniotomy pain is located around the scar and external inguinal ring and is often described as deep rather than cutaneous, with frequent complaints of pain in adjacent areas. Whether this pain is due to local pathology or referred/projected pain is unknown, hindering mechanism-based treatment. METHODS: Deep tissue electrical pain stimulation by needle electrodes in the right groin (rectus muscle, ilioinguinal/iliohypogastric nerve and perispermatic cord) was combined with assessment of referred/projected pain and the cutaneous heat pain threshold (HPT) at three prespecified areas (both groins and the lower right arm) in 19 healthy subjects. The assessment was repeated 10 days later to assess the reproducibility of individual responses. RESULTS: Deep electrical stimulation elicited pain at the stimulation site in all subjects, and in 15 subjects, pain from areas outside the stimulation area was reported, with 90-100% having the same response on both days, depending on the location. Deep pain stimulation significantly increased the cutaneous HPT (P<0.014). Individual HPT responses before and during deep electrical pain stimulation were significantly correlated (ρ>0.474, P≤0.040) at the two test days for the majority of test areas. CONCLUSION: Our results corroborate a systematic relationship between deep pain and changes in cutaneous nociception. The individual referred/projected pain patterns and cutaneous responses are variable, but reproducible, supporting individual differences in anatomy and sensory processing. Future studies investigating the responses to deep tissue electrical stimulation in persistent postherniotomy pain patients may advance our understanding of underlying pathophysiological mechanisms and strategies for treatment and prevention. TRIAL REGISTRY NUMBERS: ClinicalTrials.gov (NCT01701427).

Hip and groin pain in male field hockey players: Prevalence, incidence and associations with patient reported outcome scores and hip muscle strength.

OBJECTIVES: Investigate point prevalence (second half season 2018-2019) and incidence (season 2017-2018 and first half season 2018-2019) of non-time-loss and time-loss hip/groin pain in male field hockey players. Secondary aims were to study associations between: current/previous hip/groin pain and hip muscle strength, patient reported outcome measures (PROM) and hip muscle strength, and previous hip/groin pain and PROMs. Additionally we studied normal values for the PROMs (Hip and Groin Outcome Score (HAGOS)). DESIGN: Cross-sectional study. SETTING: Testing at field hockey clubs. PARTICIPANTS: 100 male field hockey players (elite, sub-elite and amateur). MAIN OUTCOME MEASURES: Point prevalence and incidence of hip/groin pain, strength: eccentric adduction and abduction, adductor squeeze, HAGOS. RESULTS: Hip/groin pain point prevalence was 17% (time-loss: 6%) and incidence was 36% (time-loss: 12%). Presence of current or previous hip/groin and lower HAGOS-values were not associated with lower hip muscle strength. Previous hip/groin pain was associated with a significant lower HAGOS-values in all domains, except for the 'participation in physical activities' domain. CONCLUSIONS: Hip/groin pain is common in field hockey. One fifth of players have hip/groin pain and one third had pain in the previous season. Previous hip/groin pain was associated with worse ongoing patient reported outcomes in most domains.

Rapid Spike in Hip Adduction Strength in Early Adolescent Footballers: A Study of 125 Elite Male Players From Youth to Senior.

PURPOSE: To investigate the differences in hip adductor and abductor muscle strength in elite male footballers from youth to senior level. METHODS: We tested 125 players from the under-13-years (U'13) to senior squads of a Danish male professional football club in this cross-sectional design study. Hip adductor and abductor force (in newtons), torque (in newton meters), normalized torque (in newton meters per body mass), and adduction-to-abduction ratio were measured using handheld dynamometry. RESULTS: Between U'13 and senior level, adductor force increased by 104%, torque by 127%, and normalized torque by 21%. Abductor force increased by 78%, torque by 126%, and normalized torque by 17%. For incremental differences between age groups, significant increases were observed between the ages of U'13 to U'14 (18%-39%) and U'14 to U'15 (19%-33%) for all strength measures (P ≤ .021). No incremental difference was observed for adductor-to-abductor ratio. CONCLUSIONS: The large increases in hip adductor and abductor strength occurring between the ages of U'13 and U'15 offer insight into the strength capabilities and stress demands in these players, which may relate to injury vulnerability, and facilitate clinicians in selecting best-suited exercise interventions.

Hip and groin function and strength in male ice hockey players with and without hip and groin problems in the previous season- a prospective cohort study.

OBJECTIVE: To describe and compare hip and groin strength and function of male ice hockey players over one season in players with and without hip and groin problems in the previous season. DESIGN: Prospective cohort study. SETTING: Swedish male ice hockey. PARTICIPANTS: We followed 193 players from 10 teams during the 2017/2018 season. MAIN OUTCOME MEASURES: Hip adduction and abduction strength, 5 s squeeze test (5SST), and self-reported hip and groin function (Hip and Groin Outcome Score). Changes over the season and differences between players with and without problems in the previous season were analyzed by linear mixed models. RESULTS: Adduction strength decreased slightly from pre-to mid-season and abduction strength increased slightly over the full season. However, self-reported function or pain did not change. Players with hip and groin problems in the previous season had significantly worse self-reported function, and more groin pain during the 5SST compared to players without. Strength measurments did not differ between groups. CONCLUSIONS: Hip muscle strength, groin pain, and self-reported function appear to remain stable throughout the season in male ice hockey players. Remaining impairments in players with problems in the previous season suggest that function does not recover by ice hockey participation alone.

Do hip and groin muscle strength and symptoms change throughout a football season in professional male football players? A prospective cohort study with repeated measures.

OBJECTIVES: Groin injuries are common in professional male football and result in significant complaints, time-loss and cost. We aimed to study: 1. Normal values of hip muscle strength and self-reported hip and groin function (Hip And Groin Outcome Score (HAGOS)). 2. Changes in these values throughout the season. 3. If previous (groin) injuries, leg dominance or league were associated with these outcome measures. DESIGN: Prospective cohort study. METHODS: 313 professional male football players (11 clubs) participated. Player characteristics and previous injuries were registered. Hip muscle strength (hand-held dynamometer) and HAGOS measurements were done at the start, middle and end of the season. RESULTS: Data from 217 players were analysed. Adduction strength (mean±standard deviation, Nm/Kg) was 3.40±0.72 (start), 3.30±0.65 (mid) and 3.39±0.74 (end) (p=0.186). Abduction strength was 3.45±0.67, 3.14±0.57 and 3.28±0.61 (p<0.001). Adduction/abduction ratio was 1.00±0.21, 1.07±0.22 and 1.05±0.23 (p<0.001). Statistically, the HAGOS-subscale 'Pain' (median [interquartile range]) deteriorated slightly during the season (p=0.005), especially from mid-season (97.5 [90.6-100.0]) to end-of-season (95.0 [87.5-100.0]) (p=0.003). Other subscale scores remained unchanged between time points; 85.7 (symptoms), 100.0 (daily living), 96.9 (sports and recreation) 100.0, (physical activities) and 90.0 (quality of life). Previous injuries were associated with lower HAGOS-scores. Dominant legs had higher abduction strength (p<0.001) and lower adduction/abduction ratio (p<0.001). No differences between leagues were found for hip muscle strength and HAGOS-scores. CONCLUSIONS: In Dutch male professional football players, hip muscle strength and HAGOS-scores remained relatively stable throughout the season. Pain increased slightly, which while statistically significant, was not clinically relevant.

Field-based evaluation of hip adductor and abductor strength in professional male ice hockey players: Reference values and influencing factors.

OBJECTIVES: To provide reference values and examine the influence of hip/groin pain on hip adductor and abductor strength in professional male ice hockey players, by using a straightforward 5-min procedure. DESIGN: Cross-sectional study. SETTING: On-field assessment of hip/groin muscle strength with dynamometry, together with the concomitant level of hip/groin pain with a visual analogue scale. PARTICIPANTS: Professional male ice hockey players competing in the Swiss National League (n = 187). MAIN OUTCOME MEASURES: Hip abductor strength, hip adductor strength and hip adductor:abductor ratio. RESULTS: Reference values by playing position (goalkeepers, defenders and forwards) are provided for asymptomatic athletes. Players with hip/groin pain during adduction displayed lower hip adductor strength (p = 0.001) and hip adductor:abductor ratio (p = 0.012) than their symptom-free peers. CONCLUSIONS: The presence of hip/groin pain during adductor testing may contribute to selective hip adductor weakness, whose cause-effect relation with possible groin problems remains to be demonstrated.

The anatomy of the pubic region revisited: implications for the pathogenesis and clinical management of chronic groin pain in athletes.

Chronic groin pain is a common complaint for athletes participating in sports that involve repetitive sprinting, kicking or twisting movements, such as Australian Rules football, soccer and ice hockey. It is frequently a multifactorial condition that presents a considerable challenge for the treating sports medicine practitioner. To better understand the pathogenesis of chronic groin pain in athletes, a precise anatomical knowledge of the pubic symphysis and surrounding soft tissues is required. Several alternative descriptions of pubic region structures have been proposed. Traditionally, chronic groin pain in athletes has been described in terms of discrete pathology requiring specific intervention. While this clinical reasoning may apply in some cases, a review of anatomical findings indicates the possibility of multiple pathologies coexisting in athletes with chronic groin pain. An appreciation of these alternative descriptions may assist sports medicine practitioners with diagnostic and clinical decision-making processes. The purpose of this literature review is to reappraise the anatomy of the pubic region, considering findings from cadaveric dissection and histology studies, as well as those from diagnostic imaging studies in athletes.

De novo generation of axially vascularized tissue in a large animal model.

De novo generation of axially vascularized tissue with clinically relevant dimensions in a large animal model and implementation of clinically established imaging modalities for in vivo evaluation of vascularization. To be used for reconstruction of tissue defects, engineered grafts need to be axially vascularized to enable transplantation without graft loss due to hypoxia. Limitations to dimensions in small animal models had not yet been overcome, which is necessary to yield clinical relevance. Anatomical studies of groin and axillary regions in eight merino sheep were followed by microsurgical creation of an arteriovenous loop (AV-loop), embedded in an isolation chamber filled with fibrin matrix. Constructs were implanted in the groin of six sheep for up to 6 weeks. Course of vascularization in de novo forming tissue was assessed by sequential computed tomography angiography (CTA) and magnetic resonance angiography (MRA) in vivo, as well as by postexplantational micro-computed tomography and histology. A vascular axis was constantly found epifascially at the medial aspect of all sheep's thighs, which was used for AV-loop creation. Patency of AV-loop could be visualized by CTA and MRA scans during 1-6 weeks. Complex 3D-vessel-reconstruction revealed increasing axial vascularization of the fibrin matrix and growing connective tissue within the isolation chamber, which was confirmed by micro-computed tomography and histology postexplantation. De novo formation of axially vascularized tissue was demonstrated for the first time ever in a large animal model, paving the way for the first application of tissue engineering vascularized grafts with clinically relevant dimensions.

Adductor longus mechanics during the maximal effort soccer kick.

Groin pain is a common cause of athletic disability and often involves the adductor longus. A common complaint of patients with groin problems is pain while preparing to kick the ball. The purpose of this study was to examine muscle length and activation of the adductor longus while kicking a soccer ball. Three-dimensional joint positions and muscle activation were obtained from 15 National Collegiate Athletic Association (NCAA) Division 1 male soccer players during maximal effort kicks. Musculoskeletal modeling techniques incorporating joint position and muscle attachments were used to estimate adductor longus length from the beginning of the kicking leg's swing phase until ball strike. The maximum rate of stretch of the adductor longus (22.3 +/- 5.3 cm/s) and maximum hip extension (23.3 +/- 8.80) occurred near 40% of swing phase. Activation of the adductor longus occurred between 10% and 50% of the swing phase. Adductor longus maximum length occurred at 65% of the swing phase. Maximum hip abduction (25.3 +/- 5.40) occurred at 80% of swing phase. The adductor longus appears to be at risk of strain injury during its transition from hip extension to hip flexion. This knowledge could be applied to muscle injury prevention and rehabilitation programs to aid with treatment of adductor longus related groin pain.

In-season monitoring of hip and groin strength, health and function in elite youth soccer: Implementing an early detection and management strategy over two consecutive seasons.

OBJECTIVES: The primary purpose of this study was to describe an early detection and management strategy when monitoring in-season hip and groin strength, health and function in soccer. Secondly to compare pre-season to in-season test results. DESIGN: Longitudinal cohort study. METHODS: Twenty-seven elite male youth soccer players (age: 15.07±0.73years) volunteered to participate in the study. Monitoring tests included: adductor strength, adductor/abductor strength ratio and hip and groin outcome scores (HAGOS). Data were recorded at pre-season and at 22 monthly intervals in-season. Thresholds for alerts to initiate further investigations were defined as any of the following: adductor strength reductions >15%, adductor/abductor strength ratio <0.90, and HAGOS subscale scores <75 out of 100 in any of the six subscales. RESULTS: Overall, 105 alerts were detected involving 70% of players. Strength related alerts comprised 40% and remaining 60% of alerts were related to HAGOS. Hip adductor strength and adductor/abductor strength ratio were lowest at pre-season testing and had increased significantly by month two (p<0.01, mean difference 0.26, CI95%: 0.12, 0.41N/kg and p<0.01, mean difference 0.09, CI95%: 0.04, 0.13 respectively). HAGOS subscale scores were lowest at baseline with all, except Physical Activity, showing significant improvements at time-point one (p<0.01). Most (87%) time-loss were classified minimal or mild. CONCLUSIONS: In-season monitoring aimed at early detection and management of hip and groin strength, health and function appears promising. Hip and groin strength, health and function improved quickly from pre-season to in-season in a high-risk population for ongoing hip and groin problems.

Return to Sport and Performance After Hip Arthroscopy for Femoroacetabular Impingement in 18- to 30-Year-Old Athletes: A Cross-sectional Cohort Study of 189 Athletes.

BACKGROUND: A recent systematic review found that 87% of athletes return to sport after hip surgery for femoroacetabular impingement syndrome. However, the proportion of athletes returning to preinjury sport at their preinjury level of sport is less clear. PURPOSE: The main purpose of this study was to determine the rate of athletes returning to preinjury sport at preinjury level including their associated sports performance after hip arthroscopy for femoroacetabular impingement syndrome. Furthermore, self-reported hip and groin function was investigated. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Eligible subjects were identified in the Danish Hip Arthroscopy Registry. A self-reported return to sport questionnaire was used to collect data after hip arthroscopy. If athletes reported they were engaged in preinjury sport at their preinjury level, the associated sports performance and participation were assessed as either (1) optimal sports performance including full sports participation; (2) impaired sports performance, but full sports participation; or (3) impaired sports performance including restricted sports participation. Self-reported hip and groin function was assessed for all athletes by use of the Copenhagen Hip and Groin Outcome Score. RESULTS: The study included 189 athletes (mean ± SD age at follow-up, 26.9 ± 3.4 years) at a mean ± SD follow-up of 33.1 ± 16.3 months after surgery. At follow-up, 108 athletes (57.1%) were playing preinjury sport at preinjury level, whereas the remaining 81 athletes (42.9%) failed to return to preinjury sport at preinjury level. Of the 108 athletes engaged in their preinjury sport at preinjury level at follow-up, 32 athletes (29.6%) reported optimal sports performance including full sports participation, corresponding to 16.9% of the study sample. Better self-reported hip and groin function was observed in athletes who were engaged in preinjury sport at preinjury level compared with athletes who were not. CONCLUSION: Fifty-seven percent of athletes returned to preinjury sport at their preinjury level. This is considerably lower than a previously reported return to sport rate of 87% and may reflect that the present study used a clear and strict definition of return to sport. Of note, only one-third of athletes who returned to preinjury sport at preinjury level reported their sports performance to be optimal, corresponding to 16.9% of the study sample. Better self-reported hip and groin function was observed in athletes who were playing preinjury sport at preinjury level compared with athletes who were not.

The precision and torque production of common hip adductor squeeze tests used in elite football.

OBJECTIVES: Decreased hip adductor strength is a known risk factor for groin injury in footballers, with clinicians testing adductor strength in various positions and using different protocols. Understanding how reliable and how much torque different adductor squeeze tests produce will facilitate choosing the most appropriate method for future testing. In this study, the reliability and torque production of three common adductor squeeze tests were investigated. DESIGN: Test-retest reliability and cross-sectional comparison. METHODS: Twenty elite level footballers (16-33 years) without previous or current groin pain were recruited. Relative and absolute test-retest reliability, and torque production of three adductor squeeze tests (long-lever in abduction, short-lever in adduction and short-lever in abduction/external rotation) were investigated. Each participant performed a series of isometric strength tests measured by hand-held dynamometry in each position, on two test days separated by two weeks. RESULTS: No systematic variation was seen for any of the tests when using the mean of three measures (ICC=0.84-0.97, MDC%=6.6-19.5). The smallest variation was observed when taking the mean of three repetitions in the long-lever position (ICC=0.97, MDC%=6.6). The long-lever test also yielded the highest mean torque values, which were 69% and 11% higher than the short-lever in adduction test and short-lever in abduction/external rotation test respectively (p<0.001). CONCLUSIONS: All three tests described in this study are reliable methods of measuring adductor squeeze strength. However, the test performed in the long-lever position seems the most promising as it displays high test-retest precision and the highest adductor torque production.

Normative adductor squeeze tests scores in rugby.

BACKGROUND: Groin pain is a common problem. Adductor squeeze tests are used to diagnose, monitor and prophylactically determine the risk of developing groin pain. This study defines normative adductor squeeze scores in professional rugby that will facilitate strength monitoring during screening. METHODS: Using a sphygnamometer, squeeze scores were collected, at one professional rugby club as part of the pre-season screening for two seasons. Scores were collected in four positions. For all positions mean strength and 95% confidence intervals were calculated. RESULTS: Data were collected for 81 athletes. Mean strength for adduction at 60° was 220.1 (212.2-228.1); 0° 211.1 (201.7-220.5); 90°90° 198.8 (190.0-207.7); 90°90° supported 224.9 (214.9-234.9). Backs had lower squeeze scores than forwards for 0°, 90°:90° and 90°:90° supported (p > 0.05 for all four tests); older players had lower scores, as did shorter and lighter players (p > 0.05 except for height with test 60° p = 0.048 and test 90°:90° supported p = 0.035). CONCLUSION: This study establishes references ranges for adductor squeeze tests for normative pre-season data in non-injured rugby players. This information will enable evaluation and inform return to play judgements following adductor related injury.

Hip and groin injuries in athletes.

Although athletic injuries about the hip and groin occur less commonly than injuries in the extremities, they can result in extensive rehabilitation time. Thus, an accurate diagnosis and well-organized treatment plan are critical. Because loads of up to eight times body weight have been demonstrated in the hip joint during jogging, presumably even greater loads can occur during vigorous athletic competition. The available imaging modalities are effective diagnostic tools when selected on the basis of a thorough history and physical examination. Considerable controversy exists as to the cause and optimal treatment of groin pain in athletes, or the so-called "sports hernia." There has also been significant recent attention focused on intraarticular lesions that may be amenable to hip arthroscopy. This article briefly reviews several common hip and groin conditions affecting athletic patients and highlights some newer topics.

Survival of rat functional dental pulp cells in vascularized tissue engineering chambers.

Regenerative endodontics aims to preserve, repair or regenerate the dental pulp tissue. Dental pulp stem cells, have a potential use in dental tissue generation. However, specific requirements to drive the dental tissue generation are still obscured. We established an in vivo model for studying the survival of dental pulp cells (DPC) and their potential to generate dental pulp tissue. DPC were mixed with collagen scaffold with or without slow release bone morphogenic protein 4 (BMP-4) and fibroblast growth factor 2 (FGF2). The cell suspension was transplanted into a vascularized tissue engineering chamber in the rat groin. Tissue constructs were harvested after 2, 4, 6, and 8 weeks and processed for histomorphological and immunohistochemical analysis. After 2 weeks newly formed tissue with new blood vessel formation were observed inside the chamber. DPC were found around dentin, particularly around the vascular pedicle and also close to the gelatin microspheres. Cell survival, was confirmed up to 8 weeks after transplantation. Dentin Sialophosphoprotein (DSPP) positive matrix production was detected in the chamber, indicating functionality of dental pulp progenitor cells. This study demonstrates the potential of our tissue engineering model to study rat dental pulp cells and their behavior in dental pulp regeneration, for future development of an alternative treatment using these techniques.