Management after acute injury of the anterior cruciate ligament (ACL). Part 3: Recommendation on surgical treatment.

PURPOSE: The aim of this consensus project was to give recommendations regarding surgical treatment of the anterior cruciate ligament (ACL) injured patient. METHODS: For this consensus process, an expert, steering and rating group was formed. In an initial online meeting, the steering group, together with the expert group, formed various key topic complexes for which multiple questions were formulated. For each key topic, a structured literature search was performed by the steering group. The results of the literature review were sent to the rating group with the option to give anonymous comments until a final consensus voting was performed. Sufficient consensus was defined as 80% agreement. RESULTS: During this consensus process, 30 topics regarding the surgical management and technique of ACL reconstruction were identified. The literature search for each key question resulted in 30 final statements. Of these 30 final statements, all achieved consensus. CONCLUSIONS: This consensus process has shown that surgical treatment of ACL injury is a complex process. Various surgical factors influence patient outcomes. The proposed treatment algorithm can be used as a decision aid for the surgeon. LEVEL OF EVIDENCE: Level V.

The End of the Formal Rehabilitation Is Not the End of Rehabilitation: Knee Function Deficits Remain After Anterior Cruciate Ligament Reconstruction.

OBJECTIVE: To rate athletes' functional ability and return to sport (RTS) success at the end of their individual, formal, medically prescribed rehabilitation after anterior anterior cruciate ligament (ACL) reconstruction. METHODS: In our prospective multicenter cohort study, 88 (42 females) adults aged 18-35 years after acute unilateral ACL rupture and subsequent hamstring grafting were included. All patients were prospectively monitored during their rehabilitation and RTS process until the end of their formal rehabilitation and RTS release. As outcome measures, functional hop and jump tests (front hop, balance hops, and drop jump screening test) and self-report outcomes (Knee Injury and Osteoarthritis Outcome Score, ACL-RTS after injury) were assessed. Literature-based cut-off values were selected to rate each performance as fulfilled or not. RESULTS: At 7.5 months (SD 2.3 months) after surgery, the percentage of participants meeting the functional thresholds ranged from 4% (Knee Injury and Osteoarthritis Outcome Score SPORT) and over 44% (ACL-RTS after injury sum score) to 59% (Knee Injury and Osteoarthritis Outcome Score activities of all daily living) in the self-report and from 29% (Balance side hop) to 69% (normalized knee separation distance) in performance testing. Only 4% fulfilled all the cut-offs, while 45% returned to the same type and level of sport. Participants who successfully returned to their previous sport (type and level) were more likely to be "over-cut-off-performers." CONCLUSIONS: The low share of the athletes who fulfilled the functional RTS criteria highlights the importance of continuing the rehabilitation measures after the formal completion to assess the need for and success of, inter alia, secondary-preventive therapies.

Management after acute injury of the anterior cruciate ligament (ACL), part 2: management of the ACL-injured patient.

PURPOSE: The aim of this consensus project was to create a treatment algorithm for the management of the ACL-injured patient which can serve as an aid in a shared decision-making process. METHODS: For this consensus process, a steering and a rating group were formed. In an initial face-to-face meeting, the steering group, together with the expert group, formed various key topic complexes for which various questions were formulated. For each key topic, a structured literature search was performed by the steering group. The results of the literature review were sent to the rating group with the option to give anonymous comments until a final consensus voting was performed. Sufficient consensus was defined as 80% agreement. RESULTS: During this consensus process, 15 key questions were identified. The literature search for each key question resulted in 24 final statements. Of these 24 final statements, all achieved consensus. CONCLUSIONS: This consensus process has shown that ACL rupture is a complex injury, and the outcome depends to a large extent on the frequently concomitant injuries (meniscus and/or cartilage damage). These additional injuries as well as various patient-specific factors should play a role in the treatment decision. The present treatment algorithm represents a decision aid within the framework of a shared decision-making process for the ACL-injured patient. LEVEL OF EVIDENCE: Level V.

Management after acute rupture of the anterior cruciate ligament (ACL). Part 1: ACL reconstruction has a protective effect on secondary meniscus and cartilage lesions.

PURPOSE: The aim of this consensus project was to validate which endogenous and exogenous factors contribute to the development of post-traumatic osteoarthritis and to what extent ACL (anterior cruciate ligament) reconstruction can prevent secondary damage to the knee joint. Based on these findings, an algorithm for the management after ACL rupture should be established. METHODS: The consensus project was initiated by the Ligament Injuries Committee of the German Knee Society (Deutsche Kniegesellschaft, DKG). A modified Delphi process was used to answer scientific questions. This process was based on key topic complexes previously formed during an initial face-to-face meeting of the steering group with the expert group. For each key topic, a comprehensive review of available literature was performed by the steering group. The results of the literature review were sent to the rating group with the option to give anonymous comments until a final consensus voting was performed. Consensus was defined a-priori as eighty percent agreement. RESULTS: Of the 17 final statements, 15 achieved consensus, and 2 have not reached consensus. Results of the consensus were summarized in an algorithm for the management after ACL rupture (infographic/Fig. 2). CONCLUSION: This consensus process has shown that the development of post-traumatic osteoarthritis is a complex multifactorial process. Exogenous (primary and secondary meniscus lesions) and endogenous factors (varus deformity) play a decisive role. Due to the complex interplay of these factors, an ACL reconstruction cannot always halt post-traumatic osteoarthritis of the knee. However, there is evidence that ACL reconstruction can prevent secondary joint damage such as meniscus lesions and that the success of meniscus repair is higher with simultaneous ACL reconstruction. Therefore, we recommend ACL reconstruction in case of a combined injury of the ACL and a meniscus lesion which is suitable for repair. LEVEL OF EVIDENCE: Level V.

Additional periarticular catheter shows no superiority over single-shot local infiltration analgesia alone in unicondylar knee replacement.

PURPOSE: Local infiltration analgesia (LIA) has attracted growing interest in recent years. To prolong the positive effects of LIA, a continuous intraarticular perfusion has been introduced in total knee arthroplasty with good clinical results. The purpose of the present study was to evaluate if similar results can be obtained with the use of a continuous periarticular perfusion in unicondylar knee arthroplasty (UKA). METHODS: 50 consecutively selected patients undergoing UKA received either a single-shot LIA (control group; n = 25) or single-shot LIA combined with a continuous postoperative periarticular perfusion for 2 postoperative days (intervention group, n = 25). VAS (visual analogue scale) for pain, pain medication consumption and range of flexion were recorded postoperatively for 6 days. The catheter was removed after 2 days. RESULTS: Only minor advantages of using a continuous periarticular catheter could be shown. Patients in the intervention group showed significant lower VAS scores on day 1 and required significant less pain medication on day 6. Further, there was a significant difference in the range of flexion on day 3, on which patients of the intervention group were able to bend the knee joint on average by 12° more than patients of the control group. On the other days, any significant differences between the two groups were not observed. CONCLUSION: In summary, the present study could not identify any superiority of a periarticular catheter over single-shot LIA in UKA. Because of additional costs and the potential risk of infection, the conclusion of this study is to not recommend adding a periarticular catheter to the single-shot LIA in UKA. LEVEL OF EVIDENCE: II.

Variations in medial and lateral slope and medial proximal tibial angle.

PURPOSE: The primary objective of this study was to quantify the variations of the medial posterior tibial slope (MPTS) and the lateral posterior tibial slope (LPTS), as well as of the medial proximal tibial angle (MPTA), and to determine the fraction of patients for which standard techniques including different alignment techniques would result in alteration of the patient's individual posterior tibial slope (PTS) and MPTA. Furthermore, it was of interest if a positive correlation between PTS and MPTA or between medial and lateral slope exists. METHODS: A retrospective study was performed on CT-scans of 234 consecutively selected European patients undergoing individual total knee replacement. All measurements were done on three-dimensional CAD models, which were generated on the basis of individual CT-scans, including the hip, knee, and ankle center. Measurements included the medial and lateral PTS and the MPTA. PTS was measured as the angle between the patient's articular surface and a plane perpendicular to the mechanical axis of the tibia in the sagittal plane. MPTA was defined as the angle between the tibial mechanical axis and the proximal articular surface of the tibia in the coronal plane. RESULTS: Analysis revealed a wide variation of the MPTS, LPTS, and MPTA among the patients. MPTS and LPTS varied significantly both interindividually and intraindividually. The range of PTS was up to 20° for MPTS (from - 4.3° to 16.8°) and for LPTS (from - 2.9 to 17.2°). The mean intraindividual difference between MPTS and LPTS in the same knee was 2.6° (SD 2.0) with a maximum of 9.5°. MPTA ranged from 79.8 to 92.1° with a mean of 86.6° (SD ± 2.4). Statistical analysis revealed a weak positive correlation between MPTA and MPTS. CONCLUSION: The study demonstrates a huge interindividual variability in PTS and MPTA as well as significant intraindividual differences in MPTS and LPTS. Therefore, the question arises, whether the use of standard techniques, including fixed PTSs and MPTAs, is sufficient to address every single patient's individual anatomy. LEVEL OF EVIDENCE: III.

Surgical repair techniques, functional outcome, and return to sports after apophyseal avulsion fractures of the ischial tuberosity in adolescents.

PURPOSE: Among juvenile apophyseal avulsion injuries of the pelvis in adolescents, fractures of the ischial tuberosity are rare but sustainably debilitating. Also because informations on surgical repair options are very sparse and so far limited to general reviews, reports of individual cases or heterogeous small case series, practitioners, patients and their parental environment still feel a comprehensible hesitation regarding operative treatment. Therefore we intended to investigate patient related outcome measurements and return to sports rates after different types of surgical intervention in an own case series, so far unprecendented in its size. METHODS: Patient data of adolescents that underwent surgical intervention for a displaced apophyseal avulsion fracture of the ischial tuberosity between 01/2015 and 12/2019 in our institution were gathered. Patients were then evaluated using the hamstring injury specific Perth Hamstring Assessment Tool (PHAT). Furthermore the return to sports level in comparison to the particular pre-injury level was rated. RESULTS: Eleven adolescents with an acute or chronic mean fragment dislocation of 3.3 cm (SD ± 1.7) underwent surgical intervention in the assigned period. The mean post-operative PHAT score was 86.9 (0-100, SD ± 11.9) and thus good to excellent. The majority of adolescents (10/11) was able to return to their pre-injury sports, whereas 63.6% achieved full or nearly full level. CONCLUSIONS: Surgical refixation or restoration of aphoyseal avulsion fractures of the ischial tuberosity result in good to excellent outcomes and return to sport rates, irrespective of the type of intervention. Here prompt diagnosis with a timely intervention seems more promising than delayed interventions in chronic cases. Beyond 1.5 cm of fragment displacement affected patients should be counselled for surgical intervention.

High variability of proximal tibial asymmetry and slope: a CT data analysis of 15,807 osteoarthritic knees before TKA.

PURPOSE: As the correct rotational and sagittal alignment of the tibial tray are of key importance for optimal total knee arthroplasty (TKA) function, the objective of this study was to determine these individual variations in the proximal tibial geometry in terms of posterior tibial slope (PTS) and tibial surface asymmetry by analysing a large dataset of computer tomography (CT) information. METHODS: A retrospective two-part review was performed on 15,807 datasets that were generated during the design phase for a customized TKA implant. First, 15807 CAD (computer-aided-design) models derived from CT data were used to conduct the analysis on the variation of the PTS. Second, the axial cut of each proximal tibia in a consecutively selected subset of 2202 datasets was used to measure the tibial asymmetry. RESULTS: The majority (65.5%) of tibiae had a posterior slope between 5° and 10°, while 26.5% of knees had a slope > 10°. The asymmetry measured as offset between the lateral and medial posterior boundaries was highly variable, with overall an increasing proportion of patients with high asymmetry with increasing tibial ML width. Only 14% of tibiae exhibited symmetric (< 2 mm offset) lateral and medial plateaus, and 22% had an offset > 5 mm. CONCLUSION: This study from an extraordinary large data base reveals that tibial posterior slope and asymmetry of the tibial profile vary largely between patients receiving TKA with increasing tibial asymmetry with ML width. CT scans might help to preoperatively better select the best fitting TKA, otherwise surgeons intraoperatively will often have to deal with compromises regarding fitting, sizing and rotational issues. LEVEL OF EVIDENCE: Retrospective case series, Level IV.

Functional impairment after successful surgical reconstruction for proximal hamstring avulsion.

PURPOSE: Surgical refixation procedures after hamstring avulsion injuries show satisfying to excellent outcome results. However, for post-operative evaluation so far, used outcome scores were partially not injury-specific, heterogeneous, difficult to compare, and possibly overestimated due to ceiling effects. A new injury-specific assessment tool has recently been published, potentially depicting more realistic outcome results. Thus, the aim of our study was to evaluate patients after hamstring refixation surgery using previously utilized as well as the new Perth hamstring assessment tool (PHAT). METHODS: A series of operated hamstring injuries were retrospectively evaluated using the PHAT as well as the widespread, customized Lower Extremity Functional Scale (C-LEFS) and the customized Marx score (C-Marx). Scores as well as potential ceiling effects were evaluated individually, and compared and correlated to each other. RESULTS: Sixty-four patients were enrolled into the survey. Forty-nine questionnaires (76%) could be evaluated. The mean total PHAT score (0-100) after 28 months (SD ± 17.0) was 74.1 (SD ± 22.5) points. Mean total C-LEFS (0-80) revealed 61.4 (SD ± 18.1) points, and the mean total C-Marx score (20) was 19.4 (SD ± 1.6) points. Pearson's correlation between the individual questionnaires was high between the PHAT and the C-LEFS (r = 0.81) and low between the PHAT and C-Marx (r = 0.52) and between C-LEFS and C-Marx (r = 0.48). CONCLUSION: The presented study confirms good subjective functional outcomes after surgical intervention of hamstring avulsions in all scores. Nevertheless, using the PHAT, residual complaints are more common than often described in previous studies interpreting "conventional" scores. For future decision and patient guidance, more studies using injury-specific assessments such as the PHAT in combination with objective measurements are eligible.

Preventive lateral ligament tester (PLLT): a novel method to evaluate mechanical properties of lateral ankle joint ligaments in the intact ankle.

PURPOSE: To construct and evaluate an ankle arthrometer that registers inversion joint deflection at standardized inversion loads and that, moreover, allows conclusions about the mechanical strain of intact ankle joint ligaments at these loads. METHODS: Twelve healthy ankles and 12 lower limb cadaver specimens were tested in a self-developed measuring device monitoring passive ankle inversion movement (Inv-ROM) at standardized application of inversion loads of 5, 10 and 15 N. To adjust in vivo and in vitro conditions, the muscular inactivity of the evertor muscles was assured by EMG in vivo. Preliminary, test-retest and trial-to-trial reliabilities were tested in vivo. To detect lateral ligament strain, the cadaveric calcaneofibular ligament was instrumented with a buckle transducer. After post-test harvesting of the ligament with its bony attachments, previously obtained resistance strain gauge results were then transferred to tensile loads, mounting the specimens with their buckle transducers into a hydraulic material testing machine. RESULTS: ICC reliability considering the Inv-ROM and torsional stiffness varied between 0.80 and 0.90. Inv-ROM ranged from 15.3° (±7.3°) at 5 N to 28.3° (±7.6) at 15 N. The different tests revealed a CFL tensile load of 31.9 (±14.0) N at 5 N, 51.0 (±15.8) at 10 N and 75.4 (±21.3) N at 15 N inversion load. CONCLUSIONS: A highly reliable arthrometer was constructed allowing not only the accurate detection of passive joint deflections at standardized inversion loads but also reveals some objective conclusions of the intact CFL properties in correlation with the individual inversion deflections. The detection of individual joint deflections at predefined loads in correlation with the knowledge of tensile ligament loads in the future could enable more individual preventive measures, e.g., in high-level athletes.

Partially loaded plain radiographic measurement to evaluate rotational alignment in total knee arthroplasty.

PURPOSE: Rotational alignment of prosthetic components after total knee arthroplasty (TKA) is predominantly monitored with computer tomography (CT), for example by relating the anatomical transepicondylar axis (a-TEA) of the native femur to the posterior bicondylar axis of the prosthetic component (PBCA). The purpose of the present study was to portray a reliable, novel plain radiographic method that likewise enables the evaluation of rotational positioning of prosthetic components in TKA. Furthermore, it was intended to evaluate the prosthetic femoro-tibial functional behavior under loaded conditions. METHODS: Modified plain axial radiographs under partial weight bearing (20 kg) were performed in 63 patients (63 knees) after TKA. On the obtained radiographs, all established, relevant anatomic, and prosthetic axis and angles reflecting the rotational position of the femoral (i.e., a-TEA/PBCA angle) and tibial component were detected twice by two independent examiners with an interval of one month. Additionally, in 14 cases with anterior knee pain after surgery, radiographic results were compared to obtained computer tomography images; intraclass coefficients (ICC's) for intra- and inter-rater reliability were calculated. RESULTS: All pre-assigned axis and angles could be identified doubtlessly by both examiners in all investigated knees. For all measurements, ICC's for intra-rater and inter-rater reliability ranged from 0.75 to 0.96. The comparison of the radiographic measurements with corresponding CT results (n = 14) revealed no significant differences (p > 0.05). Rotational alignment of the tibial tray in relation to the native tibial bone was not measurable due to display overlaying. Femoro-tibial behaviour of the prosthetic components under partial loading showed a high variability. CONCLUSION: We were able to establish a new reliable radiographic technique that is able to show the most established and relevant anatomic landmarks and prosthetic axis after TKA to assess the rotational alignment of the prosthetic components in TKA in relation to the distal femur. The evaluation of the femoro-tibal behaviour instead shows a high variability and so far does not allow valid explanatory conclusions.

Biomechanical effect of unloader braces for medial osteoarthritis of the knee: a systematic review (CRD 42015026136).

PURPOSE: There is a lack of consensus regarding biomechanical effects of unloader braces for the treatment of medial osteoarthritis (OA) of the knee. The purpose of this study was to perform a systematic review of studies examining the biomechanical effect of unloader braces. METHODS: A systematic search for articles about the biomechanical effect of unloader braces was performed. Primary outcome measure was the influence of the brace on the knee adduction moment. Data sources were Pubmed central and google scholar. RESULTS: Twenty-four articles were included. Twenty articles showed that valgus unloader braces significantly decrease the knee adduction moment. Seven of those studies reported a decrease of pain in braced patients (secondary outcome measure). Positive effects on the knee adduction moment could be found for custom made braces for conventional knee braces and for a foot ankle orthosis. Four studies could not show any effect of knee unloader braces on the knee adduction moment although one of these studies found decreased pain in braced patients. One of these studies examined healthy patients with a neutral axis. CONCLUSION: This systematic review could demonstrate evidence that unloader braces reduce the adduction moment of the knee. Foresighted, a systematic review about the clinical effect of unloader braces is required.

Evaluating the potential synergistic benefit of a realignment brace on patients receiving exercise therapy for patellofemoral pain syndrome: a randomized clinical trial.

BACKGROUND: It has been previously shown that exercise programs for patellofemoral pain syndrome (PFPS) can be supported by medially directed taping. Evidence supporting the use of patellar braces is limited because previous studies have been low quality. The aim of this study is to compare the outcomes of patients with PFPS after treatment with a medially directed patellar realignment brace and supervised exercise. METHODS: In a prospective randomized multicenter trial, 156 patients with PFPS were included and randomly assigned to 6 weeks of supervised physiotherapy in combination with the patellar realignment brace, or supervised physiotherapy alone. Outcome measures were the Knee Injury and Osteoarthritis Outcome Score (KOOS) subscales, numeric analog pain scores, and the Kujala score at baseline, 6 weeks, 3 months, and 1 year after the start of therapy. The patient's self-reported perception of recovery was also assessed at these points. RESULTS: Both treatment groups showed a significant improvement in all outcome measures over the study period. After 6 and 12 weeks of therapy, patients in the brace group had significantly higher KOOS sub-scale scores, a higher mean Kujala score, and less pain while climbing stairs or playing sports. After 54 weeks a group difference could be only detected for the KOOS ADL sub-scale. CONCLUSION: The use of a medially directed realignment brace leads to better outcomes in patients with PFPS than exercise alone after 6 and 12 weeks of treatment. After 1 year of follow-up this positive effect diminished.

Early functional outcome of two different orthotic concepts in ankle sprains: a randomized controlled trial.

INTRODUCTION: Purpose of the study was the evaluation of the early functional outcome of patients with an acute ankle sprain treated either with a semirigid, variable, phase-adapted modular ankle orthosis or an invariable orthotic reference device. MATERIALS AND METHODS: Forty-seven patients with acute ankle sprain grade II or more were included. In addition, 77 healthy controls as a reference were investigated. The injured subjects were treated with one of the two devices by random for 6 weeks. Ankle scores (FAOS, AOFAS) were taken at baseline after injury, 1 and 3 months after injury. Functional performance tests (balance platform, zig zag run, shuttle run, vertical drop jump) were performed at 1 and 3 months after injury. RESULTS: No significant score differences could be found between the two intervention groups except for achieving a preinjury activity level after 3 months only in the modular orthosis group. Postural functional performances (balance test) also showed no significant differences whereas the results of the agility tests revealed small but significant better results in the modular orthosis group in comparison to the invariable orthosis group. Cohen's effect sizes were high. CONCLUSION: Differences between the two intervention groups were marginal and very small but significant and--regarding Cohen's effect sizes--effective. Especially relating to functional performance, this might be a careful indication that a more effective strategy for promoting a protected, rapid recovery to physical activity after ankle sprains might be achieved by applying a phase-adapted ankle orthosis. Especially in athletic patients, phase-adapted orthosis should be further investigated and considered to ensure fully protected ligament healing as well as to regain early functional recovery.

The Patella Pro study - effect of a knee brace on patellofemoral pain syndrome: design of a randomized clinical trial (DRKS-ID:DRKS00003291).

BACKGROUND: Patellofemoral pain syndrome (PFPS) is a frequent cause of anterior knee pain predominantly affecting young female patients who do not have significant chondral damage. Development of PFPS is probably multifactorial, involving various knee, hip, and foot kinematic factors. Biomechanical studies have described patellar maltracking and dynamic valgus (functional malalignment) in patients with patellofemoral pain syndrome. The literature provides evidence for short-term use of nonsteroidal anti-inflammatory drugs; short-term medially directed taping; and exercise programs focusing on the lower extremity, hip, and trunk muscles. Evidence supporting the use of patellar braces is limited because previous studies have been low quality. The aim of this article is to publish the design of a prospective randomized trial that examines the outcomes of patients with PFPS after treatment with a new patellar brace (Patella Pro) that applies medially directed force on the patella. METHODS/DESIGN: For this multicenter trial, 156 patients (adolescents and young adults) with PFPS were recruited from orthopedic practices and orthopedic hospitals and randomly allocated to 3 months of supervised physiotherapy in combination with the Patella Pro brace or supervised physiotherapy alone. The primary outcome measures are pain (numerical analog scale); knee function (Kujala score and Knee Injury and Osteoarthritis Outcome Score); and self-reported perception of recovery at baseline, 6 weeks, 3 months, and 1 year. DISCUSSION: Only limited evidence for the use of a patellar brace for the treatment of PFPS exists in the literature. Disputable evidence for the use of orthoses for PFPS patients has been presented in one meta-analysis, in which only one of three studies found the effect of a medially directed patellar brace to be significant. Because of these low-quality studies, the authors concluded that this evidence should be regarded as limited, and we feel there is a need for further well-designed studies to evaluate the effect of patellar bracing on PFPS-related pain. The Patella Pro study is a prospective randomized trial in which supervised physiotherapy in combination with a patellar brace is compared with supervised physiotherapy alone. This trial started in April 2012 and finished in October 2013. TRIAL REGISTRATION: DRKS-ID:DRKS00003291, January 3rd, 2012.

Residual mechanical effectiveness of external ankle tape before and after competitive professional soccer performance.

OBJECTIVE: To evaluate the presupposed preventive residual mechanical effectiveness of the widespread use of adhesive elastic ankle tape after a nonlaboratory, realistic soccer-specific outfield intervention reflecting a soccer halftime. DESIGN: A prospective nonrandomized test-retest design was used. SETTING: Laboratory. PARTICIPANTS: Seventeen professional male outfield players (mean age, 25.5) without any signs of chronic ankle instability. INTERVENTION: Participants were investigated before and after a 45-minute soccer-specific field intervention. MAIN OUTCOME MEASURES: The passive inversion range of motion (ROM) of the ankle was tested unloaded on a self-developed inversion device with and without a standardized ankle tape before and after the intervention. Additionally, electromyography signal was taken to assure the inactivity of the protective evertor muscles, and reliability tests for the inversion device (test-retest and trial to trial) were conducted in 12 healthy controls. RESULTS: Tape restricted the maximum passive inversion ROM of the uninjured ankle significantly to 50.3%. The protection declined nearly completely after 45 minutes of outfield soccer performance to a negligible nonsignificant ROM restriction of 9.7%. Pearson correlation coefficient for the reliability was 0.931 (P ≤ 0.001) for the test-retest and 0.983 (P ≤ 0.001) for the trial-to-trial test. CONCLUSIONS: The initial significant protection of external ankle-tape support declines almost completely without relevant remaining residual mechanical effect after 45 minutes, reflecting a soccer halftime. The so far presupposed residual mechanical effectiveness of tape to prevent injury is increasingly irrelevant during soccer performance and consequently antidromic to the increasing injury risk toward the end of a soccer halftime.

The TT-TG Index: a new knee size adjusted measure method to determine the TT-TG distance.

PURPOSE: Medial transfer of the tibial tubercle has become a standard procedure in cases of patella instability caused by an increased tuberositas tibae-trochlear groove (TT-TG) distance. However, the TT-TG distance has always been assessed as an absolute value without taking individual joint size into consideration. It was assumed that the pathological influence of the TT-TG distance correlates with individual joint size. Aim of the current study therefore was to develop a method to express TT-TG distance in relation to these joint variables. METHODS: Two hundred knee MRI scans of healthy individuals (69 females and 131 males) were evaluated retrospectively in a control group. First, the TT-TG distance was measured as described by Schoettle et al. To determine joint size, the proximal-distal distance between the entrance of the chondral trochlear groove (TE) and the onset of the patella tendon at the tibial tubercle (TT) was selected. Subsequently, the TT-TG/TT-TE ratio expresses the relationship between the TT-TG distance and the proximal-distal distance from the entrance of the chondral trochlear groove to the height of the tibial tubercle. The TT-TG Index can also be expressed as an angle (TT-TG angle). Likewise, in another patient group, 54 knee MRTs of patients with patellofemoral instability were evaluated. RESULTS: The average TT-TG distance of the control group was 7.5±3.5 mm (range 0-17.4 mm) with no significant differences between genders. The mean TT-TE distance was 63.9 mm (range 49-79 mm) with there being significant differences between genders. The resulting mean TT-TG Index was 0.12±0.05 (range 0-0.25). In the patient group, the average TT-TG distance was 13.5±4.1 mm and the average TT-TE distance was 61.3±6.8 mm. The resulting average TT-TG Index of 0.22±0.07 in the patient group (PFI) approximates the threshold determined by the 95% confidence interval in the healthy control group. A direct comparison between the control group and the patient group revealed a significant difference in the TT-TG distance (p=0.0001), in the TT-TE distance (p<0.0042) and in the resulting TT-TG Index (p<0.0001). CONCLUSIONS: The measurement of the TT-TG Index is a reliable and differentiated approach for determining the lateral displacement of the tibial tubercle in relation to the proximal trochlear groove. The pathological influence of the TT-TG distance in case of patella instability depends on individual joint size, confirming the initial hypothesis. We currently consider a TT-TG Index>0.23 to be pathological based on our findings. Particularly, in case of a marginal TT-TG distance, the additional relative TT-TG Index facilitates a decision concerning an indication for a operative medial transfer of the tibial tubercle. LEVEL OF EVIDENCE: II.

Patellofemoral pain syndrome.

UNLABELLED: The patellofemoral pain syndrome (PFPS) is a possible cause for anterior knee pain, which predominantly affects young female patients without any structural changes such as increased Q-angle or significant chondral damage. This literature review has shown that PFPS development is probably multifactorial with various functional disorders of the lower extremity. Biomechanical studies described patellar maltracking and dynamic valgus in PFPS patients (functional malalignment). Causes for the dynamic valgus may be decreased strength of the hip abductors or abnormal rear-foot eversion with pes pronatus valgus. PFPS is further associated with vastus medialis/vastus lateralis dysbalance, hamstring tightness or iliotibial tract tightness. The literature provides evidence for a multimodal non-operative therapy concept with short-term use of NSAIDs, short-term use of a medially directed tape and exercise programmes with the inclusion of the lower extremity, and hip and trunk muscles. There is also evidence for the use of patellar braces and foot orthosis. A randomized controlled trial has shown that arthroscopy is not the treatment of choice for treatment of PFPS without any structural changes. Patients with anterior knee pain have to be examined carefully with regard to functional causes for a PFPS. The treatment of PFPS patients is non-operative and should address the functional causes. LEVEL OF EVIDENCE: V.

Prediction profiles for nutritional supplement use among young German elite athletes.

Nutritional supplements (NS) are defined as concentrated sources of nutrients and other substances that have a nutritional or physiological effect and that are used in high frequency among athletes. The study aimed to create a prediction profile for young elite athletes to identify those athletes who have a higher relative risk for using NS. The second objective was to examine the hypothesis that the consumption of NS paves a gateway for the use of illicit drugs and doping substances. A self-designed anonymous paper-and-pencil questionnaire was used to examine the prevalence of NS consumption, doping, and illicit drug use in elite athletes with a mean age of 17 years (SD = 4 years). Logistic regression analysis was employed to assess whether NS consumption can be predicted by independent variables (e.g., biographical data, training characteristics, drug consumption behavior) to create the prediction profile for NS use. 55% and 5% of the athletes (n = 536) responded positively to having used NS and illicit drugs, respectively. Nutritional supplement consumption was positively correlated with age (OR: 1.92; CI: 1.21 to 3.05), the desire to enhance performance to become an Olympic or World Champion (OR: 3.72; CI: 2.33 to 6.01), and being educated about NS (OR: 2.76; CI: 1.73 to 4.45). It was negatively correlated with training frequency (OR: 0.55; CI: 0.35 to 0.86) and the use of nicotine (OR: 0.29; CI: 0.1 to 0.74) but did not correlate with illicit drug use and alcohol consumption. The present results show that NS are used on a large scale in elite sports. The prediction profile presented in this article may help to identify those athletes who have a high risk for using NS to plan potential education and prevention models more individually.

Anterior knee pain after total knee arthroplasty: a narrative review.

Anterior knee pain is one of the most common causes of persistent problems after implantation of a total knee replacement. It can occur in patients with or without patellar resurfacing. As a result of the surgical procedure itself many changes can occur which may affect the delicate interplay of the joint partners in the patello-femoral joint. Functional causes of anterior knee pain can be distinguished from mechanical causes. The functional causes concern disorders of inter- and intramuscular coordination, which can be attributed to preoperative osteoarthritis. Research about anterior knee pain has shown that not only the thigh muscles but also the hip and trunk stabilising muscles may be responsible for the development of a dynamic valgus malalignment. Dynamic valgus may be a causative factor for patellar maltracking. The mechanical causes of patello-femoral problems after knee replacement can be distinguished according to whether they increase instability in the joint, increase joint pressure or whether they affect the muscular lever arms. These causes include offset errors, oversizing, rotational errors of femoral or tibial component, instability, maltracking and chondrolysis, patella baja and aseptic loosening. In these cases, reoperation or revision is often necessary.