Left Tendon Research Articles

The Effect of Autologous Platelet Rich Plasma in the Treatment of Achilles Tendon Ruptures

Objectives:The aim of this study was to determine the effect of autologous platelet rich plasma (PRP) in the treatment of Achilles tendon ruptures in rabbits.Methods:The study included 14 New Zealand albino rabbits that were divided randomly into 2 groups, A and B, each containing seven rabbits. On day zero, all 28 Achilles tendons were tenotomized and repaired. In group A, the tendons were injected with PRP post surgery whereas those in group B were left untreated. On day 28, the right tendons in both groups were examined histopathologically via both light and electron microscopy, and the left tendons were subjected to biomechanical testing.Results:The histological and biomechanical findings in group A were better than those in group B, but the difference was not significant.Conclusion:PRP had no effect on the healing process 28 days post Achilles tendon rupture.

Illusory movements induced by tendon vibration in right- and left-handed people.

Frequency-specific vibratory stimulation of peripheral tendons induces an illusion of limb movement that may be useful for restoring proprioceptive information in people with sensorimotor disability. This potential application may be limited by inter- and intra-subject variability in the susceptibility to such an illusion, which may depend on a variety of factors. To explore the influence of stimulation parameters and participants' handedness on the movement illusion, we vibrated the right and left tendon of the biceps brachii in a group of right- and left-handed people with five stimulation frequencies (from 40 to 120Hz in step of 20Hz). We found that all participants reported the expected illusion of elbow extension, especially after 40 and 60Hz. Left-handers exhibited less variability in reporting the illusion compared to right-handers across the different stimulation frequencies. Moreover, the stimulation of the non-dominant arm elicited a more vivid illusion with faster onset relative to the stimulation of the dominant arm, an effect that was independent from participants' handedness. Overall, our data show that stimulation frequency, handedness and arm dominance influence the tendon vibration movement illusion. The results are discussed in reference to their relevance in linking motor awareness, improving current devices for motor ability recovery after brain or spinal damage and developing prosthetics and virtual embodiment systems.

Experimental model of Achilles tendon injury in rats.

To describe an effective experimental model to study the Achilles tendon healing. Forty male Rattus norvegicus albinus, Wistar lineage adult male weighing 250 to 300g were used for this experiment and thirty were surgically submitted to bilateral partial transverse section of the Achilles tendon. The right tendon was treated with radio waves (RF) whereas the left tendon served as control. On the third postoperative day, the rats were divided into four experimental groups consisting of ten rats each which were treated with monopolar RF adjusted to 650 kHz and 2w, for two minutes twice a week and a group of normal animals without any intervention, until they were sacrificed on the 7th, 14th and 28th days, respectively. Tendons were weighed and collagen quantification was evaluated by hydroxyprolin content. Significant reduction in collagen content on day 7, 14 and 28 was related to control experiment to normal tendon (7 days, p<0.01; 14 e 28 days, p<0.05). The experimental model has been effective and available to be used to study Achilles tendon healing.

Radiofrequency promotes more collagen synthesis than low level laser in experimental tendineous lesion (914.4)

BACKGROUND: Tendon injuries are common consequences of sports trauma and costly in terms of surgery and rehabilitation. Several therapeutic approaches have been employed to repair the tendon fibrilar matrix and restore its function. We compared the action of Low Level Laser Therapy (LLLT) and Radiofrequency (RF) after experimental lesions in rats.METHODS: Sixty adult male Wistar rats weighing 250 to 300 g were submitted to bilateral partial transverse section of the calcaneous tendon. On the third postoperative day, the rats were divided into three experimental groups consisting of ten rats each which the right tendon were treated with LLLT (Konf, Aculas ‐ HB 750) and other three treated with monopolar RF (Tonederm™). The rats were sacrificed on the 7th, 14th and 28th days. The total amount of collagen synthesized was assessed through 4‐hidroxyprolin content. The left tendon served as control in all groups.RESULTS: Collagen content in the lesions did not change at the end of the first four weeks of treatment irrespective of the method employed, even compared to controls. However RF was more effective to promote collagen synthesis than LLLT and controls after 7 (p&lt; 0.0001) and 14 days (p &lt; 0.05).CONCLUSION: RF increases collagen production in the first two weeks of treatment whereas LLLT does not. Further evaluation to ascertain the importance of this fact in the healing process in experimental tendon lesions is needed.

COLIIA1 overexpression with low level laser therapy after experimental injury (914.5)

BACKGROUND: Calcaneous tendon injuries are commonly seen as consequences of sports trauma and costly in terms of surgery and rehabilitation. Low Level Laser Therapy (LLLT) has been used to accelerate healing process and avoid tissue adhesions. We investigated the response of experimental lesions of the calcaneous tendon in rats after LLLT therapy.METHODS AND MATERIAL: Thirty adult male Wistar rats weighing 250 to 300 g were surgically submitted to bilateral partial transverse section of the calcaneous tendon. The right tendon was treated with LLLT whereas the left tendon served as control. On the third postoperative day, the rats were divided into three experimental groups consisting of ten rats each which were treated with LLLT ( Konf, Aculas ‐ HB 750), 780nm and 80mW for 20 seconds, three times/week for 7, 14 and 28 days. Collagen I, II, and III gene expression were studied.RESULTS: Increased collagen II gene expression was observed in all experimental groups.CONCLUSION: mRNA gene expression for COLIIA1 is confirmed with immunolocalization of type II collagen and suggests that it could give support to the interstitial tissues on healing process of the calcaneous tendon. Further studies are needed to confirm LLLT role in tendon healing.

Experimental model of Achilles tendon injury in rats (914.10)

Background: Injuries to tendons are among the most common injuries to the body. To determine whether a proposed animal tendon injury model is appropriate, some conditions must be met. First, the correct anatomic structure must be modeled and the desired pathologic condition must be simulated.Purpose: To describe an experimental model to study Achilles tendon healing.Methods: Forty male Rattus norvegicus albinus, Wistar lineage adult male weighing 250 to 300 g were used for this experiment and thirty were surgically submitted to bilateral partial transverse section of the Achilles tendon. The right tendon was treated with RF whereas the left tendon served as control. On the third postoperative day, the rats were divided into four experimental groups consisting of ten rats each which were treated with monopolar RF (Tonederm™) adjusted to 650 kHz and 2w, for two minutes twice a week and a group of normal animals without any intervention, until they were sacrificed on the 7th, 14th and 28th days, respectively. Tendons were weighed and collagen quantification was evaluated by hidroxyprolin content.Results: Significant reduction in collagen content on day 7, 14 and 28 was related to control experiment to normal tendon (7 days, p&lt;0.01; 14 e 28 days, p&lt;0.05).Conclusion: The experimental model has been effective and available to be used to study Achilles tendon healing.

Survival of bone marrow mesenchymal stem cells labelled with red fluorescent protein in an ovine model of collagenase-induced tendinitis

The aim of this study was to track the survival and efficacy of allogeneic bone marrow mesenchymal stem cells (BM-MSC) marked with red fluorescent protein (BM-MSCRFP) in an ovine model of collagenase-induced tendinopathy. Bone marrow was harvested from one donor sheep and BM-MSC were isolated, cultivated and transfected with red fluorescent protein (BM-MSCRFP). Collagenase was injected into both Achilles tendons in the remaining nine sheep. After two weeks the left tendon was injected with a solution of 6 x 10⁶ BM-MSCRFP and fibrin glue, while only fibrin glue was administered to the contra-lateral tendon in each sheep. After three, four and six weeks the tendons were harvested and evaluated for morphology, collagen I deposition, presence of CD34+ cells, and fluorescent labelled BM-MSC. We demonstrated that delivery of BM-MSC into tendon lesions had positive effects on the injured tendons. The BM-MSCRFP survived at three, four and six weeks after treatment, leading to better quality healing of tendons as compared to the controls, where no labelled cells were detected. Interestingly, we demonstrated high expression of CD34+ cells in tendons that had been treated with BM-MSCRFP. Mesenchymal stem cell allografts have a positive effect on tendon healing and local injection of BM-MSC directly into the tendon allows the homing of BM-MSC for good efficiency of engraftment.

Increased mast cell numbers in a calcaneal tendon overuse model.

Tendinopathy is often discovered late because the initial development of tendon pathology is asymptomatic. The aim of this study was to examine the potential role of mast cell involvement in early tendinopathy using a high-intensity uphill running (HIUR) exercise model. Twenty-four male Wistar rats were divided in two groups: running group (n = 12); sedentary control group (n = 12). The running-group was exposed to the HIUR exercise protocol for 7 weeks. The calcaneal tendons of both hind limbs were dissected. The right tendon was used for histologic analysis using Bonar score, immunohistochemistry, and second harmonic generation microscopy (SHGM). The left tendon was used for quantitative polymerase chain reaction (qPCR) analysis. An increased tendon cell density in the runners were observed compared to the controls (P = 0.05). Further, the intensity of immunostaining of protein kinase B, P = 0.03; 2.75 ± 0.54 vs 1.17 ± 0.53, was increased in the runners. The Bonar score (P = 0.05), and the number of mast cells (P = 0.02) were significantly higher in the runners compared to the controls. Furthermore, SHGM showed focal collagen disorganization in the runners, and reduced collagen density (P = 0.03). IL-3 mRNA levels were correlated with mast cell number in sedentary animals. The qPCR analysis showed no significant differences between the groups in the other analyzed targets. The current study demonstrates that 7-week HIUR causes structural changes in the calcaneal tendon, and further that these changes are associated with an increased mast cell density.

Right hand knob infarction

A 69-year-old man presented at the ER with paresis of the left arm since one week. Except for hypertension and lumbosciatic pain, there was no past medical history. Clinical examination showed spontaneous pronation of the left forearm, decreased flexion of the left elbow and decreased dorsiflexion of the left wrist. Examination of the left hand revealed impossible flexion and extension of the fourth and fifth finger, impossible opposition of the fifth finger and decreased abduction of the third, fourth and fifth fingers. There were no sensory symptoms. There was a mild hyperreflexia of the left biceps tendon reflex. Coordination and muscle strength were normal in the left leg and on the right side of the body. Cranial nerves were normal as well. Non-contrast enhanced CT of the brain performed shortly after admission at the ER showed blurring and hypodensity of the grey–white matter of the right ‘‘hand knob’’ motor area. A 3T MRI of the brain with diffusionweighted sequences performed 3 days later confirmed the presence of a local infarction of the right cortical motor hand knob along with some additional smaller ischemic lesions in the right frontal and parietal lobes (Fig. 1). There was no evidence of hemorrhagic transformation on susceptibility weighted images. An MR angiogram of the neck showed a high-grade stenosis at both the proximal cervical and the cavernous segment of the right internal carotid artery. Monoparesis of the upper limb is an uncommon presentation of acute stroke with the two largest studies on the subject reporting prevalences of 2.6 and 0.7 %, respectively [1, 2]. In the acute phase these strokes can be very disabling, but most patients demonstrate a good functional long-term outcome [1, 2]. In the largest study to date on ischemic stroke presenting with isolated pure motor weakness of an upper extremity, the location of the infarcts uniformly involved the contralateral central sulcus region and the etiologies consisted of carotid artery disease (34 %), cardio-embolism (46 %) and small vessel disease (17 %) [2]. In most patients the motor hand area can easily be identified on CT and MR. The neural elements involved in motor hand function are located in a characteristic ‘‘precentral’’ knob, which most often has the form of an inverted omega (90 %) or a horizontal epsilon (10 %) when examined in the axial plane, and appears as a posteriorly directed hook (92 %) in the sagittal plane [3]. In our case, the hand knob had a horizontal epsilon shape on the right and an inverted omega shape on the left. This case emphasizes that the precentral ‘‘hand knob’’ can be easily identified in most patients and should be carefully inspected in patients who present with acute upper limb monoparesis. S. Dekeyzer M. Acou Department of Radiology and Medical Imaging, UZ Gent, De Pintelaan 185, 9000 Ghent, Belgium

Management of Injuries of Tendon Achilles at NMC Hospital NawabShah

Introduction: Tendon Achilles is largest tendon of the body and is made of fibrous tissue, descends from calf &amp; gets attached to calcaneum. The injuries of this strongest tendon are not only uncommon but disabling as well. Twenty one tendons in 20 patients were managed successfully using Bosworth repair in the | department of Orthopaedics NMC Hospital NawabShah during the period from March 2002 to April 2006. Patients &amp; Method: All patients were male and age ranged from 25 years to 55. Thirteen injuries were caused due to direct trauma, 3 patients noticed sudden jerk during high jump while playing, 3 had fall while running on plain ground and use of prolong corticosteroids caused 2 bilateral tendon injuries in one patient (Figure 1). Eleven patients sustained right side injury while 9 had their left side tendon injury. All patients were admitted through OPD &amp; Emergency | departments and were operated after their pre-op work &amp; anesthetist’s fitness was completed. Period lapsed from injury to admission was one day to 3 months and surgery was performed within 1day to 6 days after their admissions (Figure 3). Results: All twenty patients healed completely. Out of these 20 patients 17 were farmers, one medical professional and two were agriculture mechanics (Figure 4). Follow-up period in all these patients was over 15 months and no patient lost to follow- ups.Conclusion: Public awareness service programs and interaction between Orthopaedic consultants and other health professionals including general practitioners of the areas can prevent not only delay in diagnosing such problems, but shall minimize the ailment suffered by these patients. Nevertheless, all injuries of tendon Achilles should be dealt immediately to restore the full function of this strongest tendon of body regardless the lapse of any length of time.

Probable avulsion of the infraspinatus tendon of insertion in a Rottweiler

CASE HISTORY: An 8.5-month-old male Rottweiler was presented with chronic, non-localisable, right forelimb lameness. CLINICAL FINDINGS: Survey radiographs revealed panosteitis in the right antebrachium and an irregularly marginated radiolucency on the lateral aspect of the proximal left humerus. The tendon of insertion of the left infraspinatus muscle was enlarged, some tendon fibres ended prematurely in a cluster of mineralised particles, and there was a large bony defect at the point of insertion. DIAGNOSIS: Probable avulsion of the left infraspinatus tendon. CLINICAL RELEVANCE: This case was particularly unusual due to the marked prominence of the lesion without lameness of the left forelimb. Avulsion of the infraspinatus tendon is poorly described in the veterinary and medical literature.

Changes of SM Muscles After STG Harvest

Semimembranosus (SM) muscle as well as Semitendinosus-Gracilis (STG) tendon have the same role in knee flexion and tibial internal rotation. Because STG tendons are generally used for anterior cruciate ligament (ACL) reconstruction, some compensational changes in SM muscle might have been induced. The purpose of this study was to investigate the changes of SM muscle affected by harvesting STG tendons. 10 Wistar-strain male rats were divided into control (C) and STG-dissected (STG) groups. Left STG tendons including the distal half of muscle portions were dissected in group STG and only skin incision was performed in group C. 4 weeks after the treatments, fiber types classification and ultrastructural observations were performed. In group STG the decrease of type IIa (fast-twitch fiber with high oxidative capacity) was observed in deep layers of SM muscle (p<0.01). In ultrastructural observations, the increase in lipid droplets and mitochondria and the irregularity of Z disc were observed in deep layers. These morphological changes indicated that the mechanical loading might increase in SM muscle after harvesting of STG. Because of minor injuries in SM muscle, hamstring strength exercise at early stage of rehabilitation program should be carefully performed following ACL reconstruction using STG tendons in clinical practice.

An experimental study of low-level laser therapy in rat Achilles tendon injury

The aim of this controlled animal study was to investigate the effect of low-level laser therapy (LLLT) administered 30 min after injury to the Achilles tendon. The study animals comprised 16 Sprague Dawley male rats divided in two groups. The right Achilles tendons were injured by blunt trauma using a mini guillotine, and were treated with LLLT or placebo LLLT 30 min later. The injury and LLLT procedures were then repeated 15 hours later on the same tendon. One group received active LLLT (λ = 904 nm, 60 mW mean output power, 0.158 W/cm2 for 50 s, energy 3 J) and the other group received placebo LLLT 23 hours after LLLT. Ultrasonographic images were taken to measure the thickness of the right and left Achilles tendons. Animals were then killed, and all Achilles tendons were tested for ultimate tensile strength (UTS). All analyses were performed by blinded observers. There was a significant increase in tendon thickness in the active LLLT group when compared with the placebo group (p < 0.05) and there were no significant differences between the placebo and uninjured left tendons. There were no significant differences in UTS between laser-treated, placebo-treated and uninjured tendons. Laser irradiation of the Achilles tendon at 0.158 W/cm2 for 50 s (3 J) administered within the first 30 min after blunt trauma, and repeated after 15 h, appears to lead to edema of the tendon measured 23 hours after LLLT. The guillotine blunt trauma model seems suitable for inflicting tendon injury and measuring the effects of treatment on edema by ultrasonography and UTS. More studies are needed to further refine this model.

Élastographie transitoire du tendon calcanéen : résultats préliminaires et perspectives

PurposeTo evaluate transient ShearWave elastography of the normal Achilles’ tendon. Patients and methodsThe Achilles’ tendon of 30 normal subjects were prospectively assessed using a Rubi V1Sq prototype (Supersonic Imagine). Quantitative elastography maps displayed in kilopascals with a scale of 0 to 600kPa were generated from transverse and longitudinal images at 3 different levels of plantar flexion. Subgroups were compared and analyzed based on proven or suspected variation factors (age, gender, level of physical activity). ResultsOn sagittal images, mean elasticity was 104±46kPa during extension, 464±144kPa in neutral position and 410±196kPa during maximum dorsiflexion. There was significant increase in elasticity when the Achilles’ tendon was maximally stretched (p<0.01). The intra-individual correlation between right and left tendons during ankle extension was good (Pearson Coefficient 0.8; p<0.01). Finally, physically active subjects showed significantly greater elasticity than non-active subjects (p<0.05). ConclusionTransient ShearWave elastography of the Achilles’ tendon is a simple technique that provides real-time information about tissue elasticity.

Stun gun induced myotendinous injury of the iliopsoas and gluteus minimus

We report a 57-year-old man with a complete tear of his iliopsoas tendon at the distal myotendinous junction, a near complete tear of the iliopsoas tendon at the lesser trochanter of the femur, and a high-grade tear of his gluteus minimus tendon at the greater trochanter of the femur after being struck by a stun gun in the proximal left thigh. The stun gun discharge resulted in a forced contraction of the left hip flexor muscles, which resulted in pain, weakness and difficulty with active hip flexion. Three months after the being struck with the stun gun, the patient underwent magnetic resonance imaging (MRI) of the left hip. MRI of the left hip revealed a complete tear of the left iliopsoas tendon from the lesser trochanter with 4cm of proximal retraction and a high-grade strain of the gluteus minimus tendon at the greater trochanter. The distal iliopsoas myotendinous junction and lesser trochanter tendon insertion were surgically repaired. This case illustrates that a stun gun can cause acute rupture of the iliopsoas tendon and tear of the gluteus minimus tendon, which is well visualized on MRI.

Xanthome der Achillessehnen als Leitsymptom der Sitosterinämie

The circumference of both Achilles tendons had gradually increased over the years in a now 32-year-old man (diameter of the left tendon 4.5 cm, of the right one 3.5 cm). This finally led to exercise-related pain in both tendons. Biopsy revealed benign deposition of xanthomata. Serum total cholesterol concentration was 261 mg/dl. Determination of various sitosterol fragments in serum gave a beta-sitosterol level of 43 mg/dl (normal range 0.3-1.7 mg/dl), characteristic of sitosterolaemia, which is an autosomal recessive disease causing intestinal hyperabsorption of a range of plant steroids closely related to cholesterol. On a diet low in plant steroids and treatment with cholestyramine (up to 32 g daily) the beta-sitosterol concentration fell, but only to 35 mg/dl, because of poor patient compliance. The patient died suddenly from coronary artery stenosis seven months after the diagnosis of sitosterolaemia.

Static and dynamic biomechanical properties of the regenerating rabbit Achilles tendon

Background Since tendons show viscoelastic behavior, dynamic viscoelastic properties should be assessed in addition to static biomechanical properties. We evaluated differences between static and dynamic biomechanical properties of the regenerating rabbit Achilles tendon following tenotomy. Methods At 3, 6, or 12 weeks after right Achilles tenotomy, the right (regenerating) and left (control) tendons were collected with the calcaneus from 49 rabbits. A unidirectional failure test and a dynamic viscoelastic test were conducted. Findings Tensile strength and Young’s modulus (static biomechanical properties) in the regenerating group at Week 6 were significantly greater than at Week 3, while at Week 12, these were significantly greater than at Week 6. However, even at Week 12, both parameters were less than in the control group. The value of tan δ represents dynamic viscoelasticity, a smaller tan δ indicates greater elasticity. tan δ for the regenerating group was significantly greater than for the control group at Week 3, but regenerating and control groups did not significantly differ at Week 6. No marked change was seen from Weeks 6 to 12 in the regenerating group, and no significant difference in tan δ was evident between the regenerating and control groups at Week 12. Interpretation Dynamic biomechanical properties of regenerating rabbit Achilles tendons may improve more rapidly than static biomechanical properties. Ability to tolerate dynamic movement in the healing Achilles tendon may improve more rapidly than ability to withstand static stresses.

Effects of different repair methods in treatment of supraspinatus tendon tear: experiment with rabbits

To compare the effects of different repair methods in treatment of supraspinatus tendon tear. Forty-five New Zealand rabbits aged 4 approximately 6 months underwent cutting off of the left supraspinatus tendon for the width of 8 mm, and then were randomly divided into 3 equal groups: Group A, undergoing suture anchor simple suture; Group B, undergoing suture anchor mattress suture; and Group C, undergoing transosseous mattress suture. Eight weeks after the operation the rabbits were killed. The shoulder girdles of 12 rabbits randomly selected from each group were used for mechanical test to determine the intensity strength of the supraspinatus tendon, and the left shoulder girdler of the other rabbits underwent decalcification, HE staining, and histological study to observe the healing of the end point of the supraspinatus tendon. Two rabbits. One in Group A and on in Group B underwent infection. The healing rate was 93.33% for both Groups A and B, and was 100% for Group C, however without significant differences among them (all>0.05). The mean maximum tension loads of the supraspinatus tendon of Groups A, B, and C were 82.39+/-20.70 N, 81.80+/-20.31 N, and 88.58+/-17.24 N respectively, however without significant differences among them (F=0.44, >0.05). Histological examination showed that at the end point the supraspinatus tendons of Groups A and B connected to the lamellar bone and that three-zone structure (tendon, cartilage, and bone) could be found at the end point of the supraspinatus tendon in Group C, but compared with the normal end point, the number of cartilage cells decreased. The effects of the 3 suture methods are not significantly different from each other for the repair of supraspinatus tendon in respect to healing rate and healing strength, but compared with the suture anchor simple suture method and suture anchor mattress suture method, the transosseous mattress suture method shows greater post-healing strength of tension and the tendon healing situation is closer to the normal tendon structure.

Persistent popliteal pain derived from cavernous hemangioma involving gracilis tendon and tendon sheath

Hemangiomas arising from tendon and tendon sheath are rarely reported, and may be confused with other lesions of tendons. In this case report, a 19-year-old woman was diagnosed with a cavernous hemangioma originating in the left gracilis tendon and tendon sheath. When her symptoms initially developed, MRI did not delineate the lesion due to the relatively small size of the tumor. Nine years after the onset of the patient's complaints of knee pain and swelling, the tumor was adequately diagnosed on physical examination and MRI, and was resected with complete relief of symptoms.

Glenoid dysplasia and bicipital tenosynovitis in a Maine coon cat

This report describes a rare case of bicipital tenosynovitis in a Maine coon cat. The cat, a three-and-half-year-old neutered female, presented with chronic weightbearing lameness of the left forelimb. Flexion of the left glenohumeral joint and extension of the left cubital joint were resented, and palpation of the biceps brachii tendon in the bicipital groove elicited pain. A mild incongruity of the joint with mild degenerative changes was seen radiographically. Glenohumeral joint dysplasia was suspected. Ultrasound examination revealed marked thickening of the bicipital tendon and moderate effusion of the left bicipital tendon sheath. Positive contrast radiography of the joint confirmed dilation of the tendon sheath. A tentative diagnosis of bicipital tenosynovitis was made and confirmed on arthrotomy. Surgical removal of osteophytes resulted in the cat being free from pain but a mild lameness recurred six months after surgery.