Tendon Width Research Articles

Ultrasound examination of achilles tendons in patients with familial hypercholesterolemia

Aim. To assess the morphometric characteristics of Achilles tendons in patients with familial hypercholesterolemia (FH) and to identify factors associated with an increase in their size.Материал и методы. Totally, 100 patients included, with severe primary hyperlipidemia, defined as an increase in total cholesterol ≥7,5 mM/L and/or lowdensity lipoprotein cholesterol ≥4,9 mM/L. All patients underwent duplex scanning of carotid arteries. Ultrasound examination of the Achilles tendons was carried out on an expert class ultrasound equipment Samsung Medison EKO 7 (Japan) with a linear sensor, frequency of 7-16 MHz. Thickness of the Achilles tendon (anteriorposterior dimension (APD)) was measured during scanning in the longitudinal section, width (transverse dimension (TD)) — scanning in the cross section. The measurements were made 2 cm proximal to the calcaneus.Results. Among the participants, 32 (32,0%) had definite/probable diagnosis of FH. In patients with definite/probable FH the mean values of APD were significantly higher in comparison with patients scored 5 or less points (DLCN) — 5,50 (4,70-6,10) mm vs. 5,00 (4,50-5,40), respectively (p=0,04). TD of Achilles tendons among this category of patients was also statistically significantly higher in comparison with the rest of patients — 14,0 (12,9-15,4) mm and 13,2 (12,2-14,2) mm, respectively (p=0,04). In correlation analysis, the relationship between the growth of patients and the APD of the Achilles tendons (r=0,34, p=0,001), the TD of the Achilles tendon (r=0,28, p=0,009), CIMT and TD of the Achilles tendons (r=0,21, p=0,05), amount of carotid plaques and TD of the Achilles tendon (r=0,26, p=0,01), total percentage of stenosis of the carotid arteries and the TD of the Achilles tendons (r=0,27, p=0,01), maximum percentage of stenosis of the carotid arteries and the TD of the Achilles tendons (r=0,28, p=0,007). According to regression analysis, factors associated with an increase in thickness of the Achilles tendons for more than 75 percentiles were male sex, diabetes mellitus, height, myocardial infarction in relatives, total percentage of stenosis of the carotid arteries and high-density lipoproteide cholesterol.Conclusion. In patients with definite/probable FH, mean values of width and thickness of the Achilles tendons were significantly higher in comparison with the rest of the patients. According to regression analysis, the factors associated with the increase in thickness of the Achilles tendons fro more than 75 percentiles were male sex, diabetes mellitus, height, myocardial infarction in relatives, total percentage of stenosis of the carotid arteries and HDL high-density lipoproteide cholesterol.

High-resolution ultrasound in the assessment of the distal biceps brachii tendinous complex.

To establish a high-resolution US technique that enables a systematic morphometric examination of the three components that form the distal biceps brachii tendinous complex; the internal bicipital aponeurosis, the distal biceps brachii tendon and the external bicipital aponeurosis (also known as lacertus fibrosus). Fifty cryopreserved cadaver body donor elbows were dissected to obtain morphometric reference values and to establish reliable landmarks for the US examination. Then, a systematic US technique was designed and validated by a one-to-one US/dissection analysis of 11 cryopreserved cadaver body donor elbows. Finally, the systematic US technique was carried out in 44 healthy volunteers and morphometric parameters were compared to those obtained in the first part of the study. Mean dissection reference values: internal bicipital aponeurosis width 39.61mm (10.02 SD) and thickness 0.75mm (0.24 SD), distal biceps brachii tendon width 8.38mm (1.87 SD) and thickness 2.73mm (0.69 SD), external bicipital aponeurosis width 11.17mm (5.84 SD) and thickness 0.85mm (0.28 SD). One-to-one US/dissection correlation was overall good (intraclass correlation coefficient 0.876, p < 0.0001). When comparing volunteer US/dissection measurements, significant differences were encountered in all measures except for internal bicipital aponeurosis width. However, the overall magnitude of such significant differences was <0.7mm. Using the systematics hereby proposed, high-resolution US is reliable for the morphometric assessment of the distal biceps brachii tendinous complex. The external bicipital aponeurosis is morphometrically the most variable structure.

Morphovolumetric Analysis of the Hoof in Standardbred Horses

Hoof conformation has been linked to catastrophic musculoskeletal injuries. Previous studies have been focused on two-dimensional measurements, thus existing knowledge on three-dimensional hoof analysis is very limited. The objective of this study was to examine the morphogeometric properties of the equine hoof using magnetic resonance imaging technology and provide a benchmark for volumetric internal and external anatomy of the hoof and to investigate the correlation between those measurements. Eighteen horses (5.8 ± 2.6 years) with no known hoof pathologies had undergone magnetic resonance imaging; transverse and mid-sagittal (T1-weighted) images were analyzed. Calibrated digital conformational pictures were also taken. In total, 14 internal and 18 external anatomy measurements were performed using Image J software. Patterns of pairwise correlations were found, that is, the distal phalanx volume was correlated with its width (r = 0.739), but not its length. Digital cushion volume was correlated with its length (r = 0.802). Navicular bone width was correlated with distal phalanx width (r = 0.710), but not deep digital flexor tendon width (r = 0.541). The distal phalanx volume and total hoof volume were correlated with the weight of the horse. Our results provide valuable linear and volumetric data for three-dimensional hoof anatomy and provide valuable information for clinicians and researchers to better identify internal hoof anatomy and differentiate pathological cases.

Ultrasonographic comparison of bilateral patellar tendon dimensions in patients treated via intramedullary tibial nailing using a transpatellar approach

ObjectiveOne of the most common complications following intramedullary nailing of a tibial shaft fracture is anterior knee pain. The etiology of pain remains unclear. Patellar tendon entry point is the most suspected reason for anterior knee pain. This study, sonographically examined the patellar tendons of patients treated via intramedullary nailing. MethodsThirty-two patients with a tibial shaft fracture requiring intramedullary nailing via a transpatellar approach were included in the study. After all patients were grouped by reference to the presence of anterior knee pain, bilateral patellar tendon ultrasonography was performed. ResultsThirty-two patients were included in the study. Patients were measured postop average in 38.3 months (10th months - 84th months). It was determined that 10 patients of total 32 (31.3%) had anterior knee pain. There were no statistically differences between study groups in the length of patellar tendon. In the painless group; patellar tendon was wider and thicker in the operated side than the non operated side. The mean differences in the thickness between operated side versus non – operated side of the painless group were 5.3 ± 1.8 in the operated side and 3.9 ± 1.4 in the non – operated side (p = 0.007 < 0.05). The corresponding values for width of the patellar tendon was 29.6 ± 3.3 in the operated side and 27.6 ± 3.8 in the non – operated side (p = 0.007 ˂ 0.05). As a result, there were no statistically significant differences between width and thickness of the patellar tendons in the painful group, on the contrary, in the painless group; patellar tendons were wider and thicker in the operated side than those in the non - operated side. Mean values for thickness of the operated and non-operated side were 5.9 ± 2.3 and 4.2 ± 2.0, respectively (p = 0.059 > 0.05). Mean values for width of the operated and non-operated side were 30.2 ± 4.5 and 28.5 ± 4.0, respectively (p = 0.103 > 0,05). ConclusionBased on the ultrasonographic investigation of their patellar tendons after intramedullary nailing of a tibial shaft fracture, in the painless patients group; the patellar tendon was wider and thicker in the operated side than the non – operated side, however, in the painful patients there were no statistically significant differences between this parameters. Although the number of patients was not sufficient to conclude precise relation between patellar tendon entry point and anterior knee pain, we determined that thicker and wider tendon might be less related to anterior knee pain. Level of evidenceLevel IV, therapeutic study.

The effect of tourniquet type and thigh conicity on the length of hamstring autograft.

We studied the effect of using wide contoured pneumatic tourniquet (PT) versus ultra-narrow sterile exsanguination tourniquet (SET) on the length of hamstring autograft for anterior cruciate ligament (ACL) reconstruction in patients with tubular and conical thighs. Fifty-eight patients undergoing ACL reconstruction between 2012 and 2013 were assigned to either SET or PT groups. We measured the tendon graft length and width as well as the patients' height, weight, and thigh circumference of 10 cm proximal to the patella and the distance from the anterior-superior iliac spine to the medial malleolus (ASIS-MM). We defined the ratio between the ASIS-MM and the thigh circumference as the conicity index (CI). All grafts were measured after folding into half, and the found value was recorded as functional graft length (FGL). Tendon graft dimensions were correlated with the individual anthropometric data and with CI in each of the groups. PT was used in 34 patients and SET on 24 patients. FGL was 12.7 ± 0.84 mean + standard deviation for the SET group versus 11.5 ± 1.61 for the PT group ( p = 0.0011) with a strong positive correlation between FGL and CI for the PT group ( R2 = 0.625; p = 2.6 × 10-8) but nonsignificant correlation for the SET ( R2 = 0.222). Graft thickness was correlated with the patient age ( R2 = 0.450) but not with CI or type of tourniquet used. We found the CI to be a better measure of thigh conicity than thigh circumference, length, height, weight, or body mass index individually. We conclude that using the SET which occupies less space on the thigh yielded significantly longer hamstring autologous ACL graft compared to the PT and the FGL became essentially independent from the CI when the SET was used.

Short-term Outcomes of Arthroscopic Debridement and Selected Acromioplasty of Bursal- vs Articular-Sided Partial-Thickness Rotator Cuff Tears of Less Than 50.

Background:While it is believed that good results can be achieved by arthroscopic debridement of partial-thickness tears (PTTs) of <50% tendon thickness, few studies have directly compared the treatment of articular- versus bursal-sided PTTs of <50%.Purpose:To compare the postoperative outcomes of patients with articular- versus bursal-sided PTTs of <50% tendon thickness that were treated with arthroscopic debridement and selective acromioplasty (for type II or III acromions).Study Design:Cohort study; Level of evidence, 3.Methods:An analysis was performed with data from 76 consecutive patients diagnosed with a PTT <50% tendon width (Ellman grade II) who had undergone arthroscopic debridement and selective acromioplasty (for type II or III acromions). Outcome measures included the short version of the Western Ontario Rotator Cuff index, the American Shoulder and Elbow Surgeons score, and the relative Constant-Murley score, as well as strength of the affected shoulder. A statistical paired t test (preoperative vs 2 years postoperative) and an independent t test were utilized to compare outcomes between patients with bursal- and articular-sided tears.Results:Between 2001 and 2010, there were 40 (53%) articular- and 36 (47%) bursal-sided tears treated with debridement and selective acromioplasty. The mean patient age was 55 years (range, 36-77 years) for the bursal group and 56 years (range, 33-81 years) for the articular group. The mean follow-up was 24 months (range, 22-26 months). Both groups showed significant improvement in the short version of the Western Ontario Rotator Cuff index, American Shoulder and Elbow Surgeons score, and relative Constant-Murley score 2 years after surgery (P < .0001) as well as in strength (P < .0001 for bursal tears, P = .006 for articular tears). There was no statistically significant difference between groups in any of the postoperative outcome measures at 2 years.Conclusion:The results of this study demonstrate that good outcomes can be achieved with arthroscopic debridement and selective acromioplasty among patients with articular- or bursal-sided PTT of <50% tendon thickness. No difference was observed between groups at 2-year follow-up.

Can Weakness in End-Range Plantar Flexion After Achilles Tendon Repair Be Prevented?

Background:Disproportionate end-range plantar flexion weakness, decreased passive stiffness, and inability to perform a heel rise on a decline after Achilles tendon repair are thought to reflect increased tendon compliance or tendon lengthening. Since this was first noted, we have performed stronger repairs and avoided stretching into dorsiflexion for the first 12 weeks after surgery.Hypothesis:Using stronger repairs and avoiding stretching into dorsiflexion would eliminate end-range plantar flexion weakness and normalize passive stiffness.Study Design:Case series; Level of evidence, 4.Methods:Achilles repairs with epitendinous augmentation were performed on 18 patients. Plantar flexion torque, dorsiflexion range of motion (ROM), passive joint stiffness, and standing single-legged heel rise on a decline were assessed at 43 ± 24 months after surgery (range, 9 months to 8 years). Maximum isometric plantar flexion torque was measured at 20° and 10° of dorsiflexion, neutral position, and 10° and 20° of plantar flexion. Passive dorsiflexion ROM was measured with a goniometer. Passive joint stiffness was computed from the increase in passive torque from 10° to 20° of dorsiflexion. Tendon thickness was measured by use of digital calipers. Plantar flexion electromyographic (EMG) data were recorded during strength and functional tests. Analysis of variance and chi-square tests were used to assess weakness and function.Results:Marked weakness was evident on the involved side at 20° of plantar flexion (deficit, 26% ± 18%; P < .001), with no weakness at 20° of dorsiflexion (deficit, 6% ± 17%; P = .390). Dorsiflexion ROM was decreased 5.5° ± 8° (P = .015), and tendon width was 8 ± 3 mm greater on the involved side (P < .001). Passive joint stiffness was similar between the involved and noninvolved sides. Only 2 of 18 patients could perform a decline heel rise on the involved side compared with 18 of 18 on the noninvolved side (P = .01). No difference in EMG amplitude was found between the involved and noninvolved sides during the strength or heel rise tests.Conclusion:The use of stronger repair techniques and attempts to limit tendon elongation by avoiding dorsiflexion stretching did not eliminate weakness in end-range plantar flexion. EMG data confirmed that end-range weakness was not due to neural inhibition. Physiological changes that alter the force transmission capability of the healing tendon may be responsible for this continued impairment. This weakness has implications for high-demand jumping and sprinting after Achilles tendon repair.

Axial Width of Patellar Tendon Beyond Lateral Trochlear Ridge: A Novel Measurement of Patellofemoral Instability

Axial Width of Patellar Tendon Beyond Lateral Trochlear Ridge: A Novel Measurement of Patellofemoral Instability

Anthropometric and clinical analysis of the distal ulna and extensor carpi ulnaris tendon using MRI.

To investigate the ulnar groove (UG), extensor carpi ulnaris (ECU) tendon, and ulnar styloid process (USP) parameters in asymptomatic individuals without ulnar-sided wrist abnormalities, to determine whether these values can be anthropometric markers of age and gender and identify their correlations for use in clinical decision-making. The MRI T1W axial, T2W sagittal, coronal PW and DESS sequences were evaluated in 100 cases (62 women). The UG width, depth and groove opening angle (GOA), ECU tendon width and thickness, and USP base width and length were measured. For gender, the cut-off, sensitivity, specificity and accuracy values were 8.58mm, 67, 68 and 66%, respectively, for UG width; 5.3mm, 53, 68 and 62%, respectively, for ECU width; and 6.4mm, 55, 74, and 67%, respectively, for USP length. There was no difference concerning age. The tendon width was 63% of the UG width and depth was approximately 51% out of the UG. UG depth was correlated with GOA and tendon thickness (p < 0.001 and 0.03, respectively); UG width with GOA, tendon thickness, and USP base width and length (p = 0.005, 0.01, 0.016, and 0.02, respectively); tendon width-thickness with USP base width and length (p = 0.05); and US base width with US length (p < 0.001). The gender differences in distal ulnar measurements can be beneficial for surgery and forensic science. UG is wider than ECU tendon, and this is the cause of normal subluxation. Therefore, rather than deepening UG, surgeons should focus on tendon sheath abnormalities as a physiological solution.

The anatomical and imaging study of pes anserinus and its clinical application.

The pes anserinus was an important graft choice for anterior cruciate ligament (ACL) reconstruction. The infrapatellar branch of the saphenous nerve (IPBSN) might be damaged in this surgery. This study aimed to provide anatomic and ultrasonic measurement data of pes anserinus and superficial nerves. Eighty lower limb specimens of forty adult cadavers were dissected. The length, width, thickness, and the position of the tibial attachment of pes anserinus tendons were anthropometric measured, as well as the distance between the infrapatellar branch of the saphenous nerve and the pes anserinus. Sixty healthy adult participants were enrolled for ultrasonic research. The length, width, thickness of pes anserinus was also measured and the saphenous nerve was also assessed. Anatomic results showed that there were 3 types of pes anserinus, the infrapatellar branch of the saphenous nerve (IPBSN) was almost paralleled to the upper edge of the pes anserinus tendon, and the average of distance between them was about 0.95 cm. The length of semitendinosus and gracilis tendons were 146.49 ± 12.83 mm and 124.62 ± 8.86 mm, the width of sartorius tendon was 25.58 ± 4.65 mm, wider than other tendons. The classification of pes anserinus tendons and the saphenous nerves could be identified in ultrasonic image. The length of semitendinosus and gracilis tendons were 151.35 ± 9.65 mm and 120.86 ± 8.99 mm, the width of sartorius tendon was 22.84 ± 3.83 mm. And there was no significance difference between anatomic and ultrasonic measurement (P > .05). The morphology of pes anserinus and its peripheral structures could be identified and measured precisely by ultrasound device, a presurgical ultrasonic examination was recommended. The arrangement of pes anserinus tendons was classified into 3 types according to our results. The incision should be performed medial to tibial eminence 1.5 cm and under the tibial tubercle level 2 to 3 cm, an oblique incision formed an angle of 50° with tibial transection was recommend, which was parallel to the direction of pes anserinus tendon.

Quantitative Characterization of Cadaveric Pronator Muscles Using 3D Modeling

The pronator muscles of the upper limb, pronator teres (PT) and pronator quadratus (PQ), work together to rotate the radius around the ulna along an axis parallel to the central bands of the interosseous membrane while stabilizing the involved joints. Anatomical variations that affect the rotational efficiency of the PT have been described. Previously, we have described an aberrant PQ with a possible flexor function, and also defined 4 types of anatomical variations in PQ, based on the number of bellies present, and whether it occurred unilaterally or bilaterally, suggesting that PQ is more variable than appreciated. The PT typically has 2 distinct heads of origin (ulnar and humeral) and inserts onto the lateral radius. However, several anatomical variations have been reported, including the number of heads, locations of origin and insertion points, anomalous fiber orientations, and the presence of fibrous bridges and/or arches. In the current study, we sought to determine if there are patterns of anatomical variations in the PT, and whether any such variations occurred in relationship to those of the PQ. Sixteen forearms from 8 embalmed cadavers (4F,4M ages 64–93, mean 82) were dissected, and the PT and PQ muscles observed for muscle shape, fascicle orientation, and attachment points. PT and PQ heads was described, and PT tendon length, width, and distance from the radial head and styloid process measured. Our data revealed that the PT existed as only a single muscle head (humeral), bilaterally, in 25% of the cadavers examined, while exhibiting the traditional two muscle heads (humeral, ulnar) bilaterally in 75% of cadavers. Interestingly, the PT variant with a single humeral head occurred in conjunction with Type II PQ muscles bilaterally (i.e., the presence of 2 muscle bellies). Of the six cadavers with both humeral and ulnar heads of PT, 33.3% had an occurred with Type I PQ (1 head, bilateral), 33.3% with Type II PQ (2 heads, unilateral), and 33.3% with Type III PQ (2–3 heads, bilaterally). Our data suggests that there may be a relationship between the patterns of anatomical variations between PT and PQ muscles, which may provide new insight into the biomechanical relationship between these 2 muscles. The inclusion of additional cadaveric specimens, as well as quantitative comparisons between PT and PQ muscles, including cross sectional area, volume, and line of action, will help to elucidate the potential relationship between PT and PQ muscles.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Biomechanical Cadaveric Evaluation of Partial Acute Peroneal Tendon Tears.

No clear guideline or solid evidence exists for peroneal tendon tears to determine when to repair, resect, or perform a tenodesis on the damaged tendon. The objective of this study was to analyze the mechanical behavior of cadaveric peroneal tendons artificially damaged and tested in a cyclic and failure mode. The hypothesis was that no failure would be observed in the cyclic phase. Eight cadaveric long leg specimens were tested on a specially designed frame. A longitudinal full thickness tendon defect was created, 3 cm in length, behind the tip of the fibula, compromising 66% of the visible width of the peroneal tendons. Cyclic testing was initially performed between 50 and 200 N, followed by a load-to-failure test. Tendon elongation and load to rupture were measured. No tendon failed or lengthened during cyclic testing. The mean load to failure for peroneus brevis was 416 N (95% confidence interval, 351-481 N) and for the peroneus longus was 723 N (95% confidence interval, 578-868 N). All failures were at the level of the defect created. In a cadaveric model of peroneal tendon tears, 33% of remaining peroneal tendon could resist high tensile forces, above the physiologic threshold. Some peroneal tendon tears can be treated conservatively without risking spontaneous ruptures. When surgically treating a symptomatic peroneal tendon tear, increased efforts may be undertaken to repair tears previously considered irreparable.

Three-dimensional quantitative analysis of healthy foot shape: a proof of concept study

BackgroundFoot morphology has received increasing attention from both biomechanics researches and footwear manufacturers. Usually, the morphology of the foot is quantified by 2D footprints. However, footprint quantification ignores the foot’s vertical dimension and hence, does not allow accurate quantification of complex 3D foot shape.MethodsThe shape variation of healthy 3D feet in a population of 31 adult women and 31 adult men who live in Belgium was studied using geometric morphometric methods. The effect of different factors such as sex, age, shoe size, frequency of sport activity, Body Mass Index (BMI), foot asymmetry, and foot loading on foot shape was investigated. Correlation between these factors and foot shape was examined using multivariate linear regression.ResultsThe complex nature of a foot’s 3D shape leads to high variability in healthy populations. After normalizing for scale, the major axes of variation in foot morphology are (in order of decreasing variance): arch height, combined ball width and inter-toe distance, global foot width, hallux bone orientation (valgus-varus), foot type (e.g. Egyptian, Greek), and midfoot width. These first six modes of variation capture 92.59% of the total shape variation. Higher BMI results in increased ankle width, Achilles tendon width, heel width and a thicker forefoot along the dorsoplantar axis. Age was found to be associated with heel width, Achilles tendon width, toe height and hallux orientation. A bigger shoe size was found to be associated with a narrow Achilles tendon, a hallux varus, a narrow heel, heel expansion along the posterior direction, and a lower arch compared to smaller shoe size. Sex was found to be associated with differences in ankle width, Achilles tendon width, and heel width. Frequency of sport activity was associated with Achilles tendon width and toe height.ConclusionA detailed analysis of the 3D foot shape, allowed by geometric morphometrics, provides insights in foot variations in three dimensions that can not be obtained from 2D footprints. These insights could be applied in various scientific disciplines, including orthotics and shoe design.

The Achilles Tendon in Healthy Subjects: An Anthropometric and Ultrasound Mapping Study

Ultrasonography is an inexpensive, fast, and reliable imaging technique widely used to assess the Achilles tendon. Although significant data exists regarding pathologic tendon changes, ultrasound data from healthy individuals are more limited. We aimed to better characterize ultrasound Achilles tendon measurements in healthy individuals and identify important correlating factors. The information collected included patient demographics, body habitus, activity level, foot dominance, and resting ankle angle. Ultrasound analysis was performed bilaterally on the Achilles tendons of 50 subjects using a high-frequency transducer to measure tendon width, thickness, cross-sectional area, and length. Males had a significantly larger mean tendon length, width, thickness, and cross-sectional area. No statistically significant difference was found in any tendon dimension between the white and black participants. Similarly, no difference was found in any tendon parameter when comparing right versus left leg dominance. Healthy subjects had a mean ankle resting angle of 45.1° ± 24° with no statistically significant difference between right and left ankles. Considering all individuals, each tendon parameter (tendon length, width, thickness, and cross-sectional area) correlated positively with subject height, weight, tibia length, and foot size. Only the Achilles cross-sectional area correlated significantly with the activity level. The resting angle of the ankle correlated positively with both tendon length and thickness. In conclusion, we found significant variations in Achilles tendon anatomy in the healthy adult population. We have thoroughly characterized significant correlations between healthy tendon dimensions and various body habitus, activity levels, and ankle parameters. Greater knowledge of the normal Achilles tendon anatomy and characterization of its variations in the healthy population will potentially allow for better pathologic diagnosis and surgical repair.

Predicting Quadrupled Graft Length and Diameter Using Single-Strand Tendon Dimensions in All-Inside Anterior Cruciate Ligament Reconstruction

To determine whether single-strand semitendinosus autograft or allograft dimensions can reliably predict quadrupled graft diameter and length. Intraoperative semitendinosus graft measurements were recorded for consecutive all-inside anterior cruciate ligament (ACL) reconstructions from 2013 to 2016 and retrospectively reviewed. Intraoperative single-strand tendon length and width and the corresponding quadrupled graft length and diameter were recorded. Pearson correlation coefficients were used to assess the linear association between single-strand width and quadrupled diameter, as well as between single-strand length and quadrupled length. Linear regression models were used to predict quadrupled values. To test the accuracy of the predicted quadrupled values, dimensions from an additional series of 30 all-inside ACL reconstructions were reviewed. Seventy-three ACL reconstruction procedures were reviewed. We excluded 12 grafts because gracilis and semitendinosus constructs were used. Thus 61 semitendinosus quadrupled grafts (30 autografts and 31 allografts) were included. Single-strand width was associated with quadrupleddiameter (P= .012), and single-strand length was associated with quadrupled graft length (P < .001). Quadrupled hamstring graft length and diameter may be accurately predicted based on length and width of the semitendinosus tendon used for all-inside, single-bundle ACL reconstruction. The ability to predict quadrupled graft dimensions can guide the surgeon in intraoperative decision making and ensure the desired ACL graft dimensions are achieved, thereby minimizing the risk of ACL reconstruction failure. Level III, retrospective comparative study.

Peroneal Tendon Tears

Category: Ankle, Basic Sciences/Biologics, Sports Introduction/Purpose: Peroneus brevis tendon tears are frequently diagnosed when ankle instability is present. No clear guideline exists as to when to repair or resect peroneal tendon tears, as most of the available literature uses Meyer’s work published in 1924 where a risk of spontaneous rupture would exist when less than 50% of the tendon remains undamaged. Our objective was to analyze the mechanical behavior of cadaveric peroneal tendons subjected to an artificially made damage, compromising 66% of its visible width and tested in a cyclic and failure phase. Our hypothesis was that no failure would be observed in the cyclic phase. Methods: 8 cadaveric foot- ankle – distal tibia specimens were included in this study. A longitudinal full thickness tendon defect was created, 3 cms in length, centered behind the tip of the fibula, compromising 66% of the visible width of the peroneal tendons as measured by a caliper. The peroneal retinaculum was kept intact. All specimens were mounted onto a special frame specifically designed for the study. All tendons were tested in a cyclic fashion using 100 repetitions between 50 N and 200 N. If no visual change or tendon failure was observed after the initial testing, a load to failure test was performed until tendon rupture or fixation failure was observed. Tendon stiffness and load to failure were registered. Statistical analysis was performed using the SPSS software. Results: No tendon failed during the cyclic testing. No defect lengthening was observed after the cyclic phase. On the failure phase, the mean load resisted by the peroneus brevis was 416 N, with a 95% confidence interval between 351 N -481 N. The mean load resisted by the peroneus longus was 723 N, with a 95% confidence interval between 578 N – 868 N. All failures were at the level of the defect created. The coefficient of variation was low for both tendons. Conclusion: A 33% of remaining peroneal tendon was able to resist very high tensile forces; therefore, it can be suggested that a 66% defect can be repaired and does not necessarily need a tenodesis as it has been historically recommended. The high resistance offered by the peroneus longus tendon offers the theoretical potential to use part of it as a free graft to repair peroneus brevis tears. The 50% rule, which determines when a peroneal tendon tear needs a tenodesis or repair, should be revisited.

Augmentationof a Distal Biceps Repair with an Acellular DermalGraft Restores Native Biomechanical Properties in a Tendon-Deficient Model

Objectives:The majority of distal biceps tendon injuries can be repaired primarily. In contrast, chronic tears with severe tendon substance deficiency and retraction often require tendon-graft augmentation. In cases with extensive partial tears of the distal biceps, human dermal allograft may be used as an alternative to restore tendon thickness and biomechanical integrity. The objective of this study was to investigate if dermal graft augmentation of an attritionally thinned distal biceps repair improved load to failure and gap formation compared with a non-augmented repair in this same tendon deficient model.Methods:18 matched specimens were organized into one of four groups - native tendon, native tendon with dermal graft augmentation, attritional defect tendon, and attritional tendon with graft. To mimic a chronic attritional biceps lesion, a defect was created leaving 30% of the tendon width intact. The repair technique in all groups consisted of a cortical button and interference screw fixation. All specimens underwent cyclical loading for 3000 cycles and were then tested to failure; gap formation and peak load at failure were documented.Results:Mean load to failure (320.9N vs. 343.8N, p=0.38) and gap formation (1.6mm vs.1.8mm, p=0.38) did not differ between the native tendon groups with and without graft augmentation. Stiffness for the repairs with the graft was 22.3 N/mm vs.19.6 N/mm (P=0.16). In the tendon deficient model, mean load to failure was significantly improved by graft augmentation (282.1N vs. 199.7N, p=0.004), whereas mean gap formation was significantly reduced (1.2mm vs. 2.7mm, p=0.04). Mean stiffness for the repairs with the graft was 11.8 N/mm vs. 7.7 N/mm (P=0.04).Conclusion:In a tendon deficient distal biceps rupture model, acellular dermal allograft augmentation restored the native tendon’s biomechanical properties. The grafted tissue deficient model demonstrated no significant differences in load to failure and gap formation compared to intact tendon. As expected, dermal augmentation of the attritional tendon repair increased the load to failure and stiffness, as well as decreased displacement compared to an un-grafted tissue deficient model. Intact native tendon showed no statistical difference or negative biomechanical consequences of dermal augmentation.

Ultrasound Measurements of Patellar Tendon: Differences Depending on Previous Training

PURPOSE:to evaluate if the lack of experience in musculoskeletal ultrasonography generates measuring errors based on patellar tendon measurements. Ultrasound is recognized as an outstanding tool in musculoskeletal pathology diagnosis, despite being physician-dependent in knowledge as much as in experience. METHODS: Six donated knees (ages 58-71 years old) were chosen for the present study. Four observers performed the measurements, which were length, thickness and width of the patellar tendon; an expert in musculoskeletal ultrasonography (gold standard), an obstetric sonographer, an orthopedic surgeon and a third-year medical student. An external participant collected all data and analyzed results. RESULTS: regarding length, an 8% mean decrease with respect to the gold standard’s mean was observed. With respect to the width, the evaluators showed lower measurements with respect to the gold standard, (less than 5% difference) with no constant systematic error, although a trend of a proportional systematic error was observed (0.59). Third, measurements from observers were an 8% higher than the gold standard’s regarding thickness. The evaluator that most approximated measurements to the gold standard performed was the obstetric sonographer. CONCLUSION: The present paper represents an approach to learning systems in musculoskeletal ultrasound and counseling courses to focus on ultrasound technique knowledge rather than anatomical domains.

Acute Response of the Infraspinatus and Biceps Tendons to Pitching in Youth Baseball.

Youth baseball frequently results in repetitive strain injuries. Quantitative ultrasound allows real-time imaging with the ability to identify acute markers of tendon change. The study objective was to determine acute quantitative ultrasound changes in the long head of the biceps and infraspinatus tendons of the throwing and nonthrowing shoulders during a pitching performance. We hypothesized the tendons of the pitching arm would exhibit an increased width and decreased echogenicity after pitching and that tendons of the nonpitching arm would not demonstrate such changes. Fifty youth baseball players, ages 9-14 yr, engaged in a simulated pitching performance that consisted of 50 pitches. Subjects underwent serial quantitative ultrasound imaging of the infraspinatus and the long head of the biceps before pitching and after 25 and 50 pitches were thrown. Testing of the change in tendon width revealed the infraspinatus (0.21 mm) and long head of the biceps tendons (0.18 mm) in the throwing shoulder had statistically significant increases (P = 0.03) in tendon width as an acute response to throwing 50 pitches, without such changes in the nonthrowing shoulder (P > 0.05). No tendon width change was found at 25 pitches in either arm or tendon (P > 0.05). No associated changes in echogenicity were found at any time point (P > 0.05). The results of this study suggest that pitching acutely increases tendon width in two biomechanically important tendons of the shoulder as early as the 50 pitch mark. This change could be a normal physiological response or a potential warning sign of future pathology and requires further study.

Anatomic study of the first extensor compartment and the relationship between the extensor tendon width and its distal insertion

The extensor pollicis brevis (EPB) tendon normally inserts into the base of the proximal phalanx of the thumb. However, a distal insertion of the EPB tendon into the thumb interphalangeal joint has been reported in refractory cases of de Quervain's disease. We hypothesized that the EPB tendon is wider beyond the thumb metacarpophalangeal joint in patients with extended EPB. This study aimed to evaluate the relationship between the extensor tendon width and the point of distal insertion of the EPB tendon. In 45 hands from 18 male and 27 female adult cadavers, the first extensor compartment was dissected and the existence of the intertendinous septum was assessed. The extensor tendon width was measured at the midpoint of the proximal phalanx, and relationships between extended EPB tendon, existence rate of the intertendinous septum, sex, and extensor tendon width were examined. Of 45 cases, intertendinous septum and extended EPB tendon were observed in 37 (82.2%) and 23 (51.1%), respectively. There was no significant difference between the existence rates of both these factors and sex. The mean extensor tendon width in the extended EPB group was significantly greater than in the normal EPB group. The cut-off value of extensor tendon width in the extended EPB group was 7.12mm. The extensor tendon width was wider in the extended EPB group than in the normal EPB group, suggesting that the differences in the EPB tendon width can be used to identify various anatomical variations in extended EPB.