The treatment of patellar tendinopathy

An Observational Study on the Prediction of Range of Motion in Soldiers Diagnosed with Patellar Tendinopathy Using Ultrasound Shear Wave Elastography

INTRODUCTION

This study hypothesized that changes in the elasticity of the quadriceps and patellar tendons before and after the diagnosis of patellar tendinopathy would correlate with the range of motion (ROM) following conservative treatment. We aimed to prospectively assess post-treatment ROM using multinomial logistic regression, incorporating elasticity measurements obtained via shear wave elastography (SWE).

MATERIALS AND METHODS

From March 2023 to April 2024, 95 patients (86 men; aged 20-45 years, mean 25.62 ± 5.49 years) underwent SWE preoperatively and two days post-diagnosis of patellar tendinopathy. Elasticity measurements of the rectus femoris, vastus medialis, vastus lateralis, patellar tendon, and biceps tendon were obtained during full flexion and extension. Based on ROM 56 days post-treatment, patients were categorized into two groups: Group A (ROM > 120 degrees) and Group B (ROM < 120 degrees). A multinomial logistic regression algorithm was employed to classify the groups using patient information and tendon elasticity measurements both at diagnosis and 1-week post-diagnosis.

RESULTS

The predictive accuracy using only patient information was 62%, while using only elasticity measurements yielded 68% accuracy. When combining patient information with elasticity measurements taken at diagnosis and two days post-diagnosis, the algorithm achieved an accuracy of 79%, sensitivity of 92%, and specificity of 56%.

CONCLUSIONS

The combination of patient information and tendon elasticity measurements obtained via SWE at pre-conservative treatment and early post-conservative treatment periods effectively predicts post-treatment ROM. This algorithm can guide rehabilitation strategies for soldiers with patellar tendinopathy.

Evaluation of Achilles Tendon Stiffness as Measured by Shear Wave Elastography in Female College Athletes Compared With Nonathletes

BACKGROUND

We sought to utilize a noninvasive technology to assess the effects of activity on Achilles tendon stiffness and define baseline Achilles tendon stiffness in female college athletes compared with nonathletes using tendon shear wave velocity as a marker for tendon stiffness.

HYPOTHESIS

Training status and exercise may affect Achilles tendon stiffness.

STUDY DESIGN

LEVEL OF EVIDENCE

Level 4.

METHODS

A total of 32 college-age female athletes were prospectively enrolled (n = 17 varsity athletes and n = 15 nonathletes). Demographic characteristics, activity level, and previous injuries were recorded. Sonographic shear wave elastography (SWE) was used to assess Achilles tendon shear wave velocity bilaterally for all subjects, both at baseline and after 2 minutes of exercise. Student t tests were used to compare the mean elastography measurements between participants stratified by athlete status and pre/postexercise stimulus. Analysis of variance (ANOVA) was used to compare the mean proximal, middle, and distal Achilles tendon elastography measurements.

RESULTS

As seen by a greater mean shear wave velocity (8.60 ± 1.58 m/s vs 8.25 ± 1.89 m/s; P = 0.02), athletes had stiffer tendons than nonathletes. Exercise stimulus decreased average tendon shear wave velocity (8.57 ± 1.74 m/s vs 8.28 ± 1.72 m/s; P = 0.05). Tendon shear wave velocity was greatest proximally and least distally with significant differences between each region (P < 0.001). In addition, there was a significant 2-way interaction between weekly training status and foot dominance (P = 0.01). Post hoc analysis showed that this result was due to differences in tendon shear wave velocity between the dominant and nondominant lower extremity in nonathletes (7.73 ± 2.00 m/s vs 8.76 ± 1.62 m/s; P < 0.001).

CONCLUSION

Female varsity collegiate athletes have higher baseline Achilles tendon stiffness as measured by SWE compared with nonathletes. Mean tendon stiffness varies based on Achilles measurement location. SWE is a quick, cost-effective, and noninvasive imaging modality that can be used to evaluate tendon stiffness and elasticity.

CLINICAL RELEVANCE

SWE is an efficient and noninvasive imaging modality that can evaluate dynamic tendon stiffness and elasticity. SWE may be helpful to assess injuries in female college athletes and may play a role in risk stratification or clinical follow-up. In theory, SWE could be used to identify athletes with increased elasticity as a marker for potential risk for rupture in this population.

Electromyographic activity of quadriceps muscles during eccentric squat exercises: implications for exercise selection in patellar tendinopathy

This study investigated the quadriceps muscle activity during eccentric squat exercises (ESE) with different decline angles and arcs of motion regarding the proper exercise selection for patellar tendinopathy management. Electromyographic activity of the rectus femoris, vastus lateralis, and vastus medialis obliquus (VMO) muscles was measured during ESE on 0°, 5°, 10°, 15°, and 20° decline in 20 recreationally active participants. The eccentric phase was divided into 0-30°, 30-60°, 60-90°, 0-60°, 30-90°, and 0-90° of knee flexion simultaneously via motion-analysis system. The analyses showed that there was a significant decline angle × arc interaction effect on electromyographic activity of all muscles during knee flexion movement. The main effect was found for the arc of motion of knee flexion, and the main effect for the decline angle also was present for each muscle, except for VMO. This study demonstrated that most selective quadriceps eccentric activation occurred during ESE performed on 20° decline throughout 60-90° of knee flexion.

Treatment of Jumper’s Knee with Extracorporeal Shockwave Therapy: A Systematic Review and Meta-Analysis

The aim of this systematic review and meta-analysis was to determine the therapeutic efficacy of extracorporeal shockwave therapy (ESWT) for athletes with patellar tendinopathy. We searched PubMed, EBSCOHost and Ovid for randomized controlled trials (RCTs) which evaluated the therapeutic efficacy of ESWT in athletes with jumper’s knee. The methodological quality of RCTs was rated with the Physiotherapy Evidence Database scale. Data in the meta-analysis were expressed as standardized mean difference (SMDs) and 95% confidence intervals (CIs). Heterogeneity was assessed with I2 statistics. Of 192 records identified, a total of seven articles met the inclusion criteria. The ESWT and control groups with any other conservative treatment did not differ significantly with respect to the Visual Analogue Scale (VAS) long-term scores obtained at ≥ 6 months of therapy completion (SMD: -0.33; 95% CI: -4.64 to 3.98; p = 0.87; I2= 98%). Furthermore, no significant differences were found between the ESWT and control groups regarding the pooled Victorian Institute of Sports Assessment for Patella (VISA-P) scores for long-term outcomes (SMD: 8.21; 95% CI: -39.3 to 55.73; p = 0.73; I2= 99%). The ESWT and control groups did not differ significantly on the VAS and VISA-P scores for long-term outcomes. In both cases, heterogeneity was considered to be high. Hence, no clear and generalized conclusions can be drawn regarding ESWT effectiveness in athletes with patellar tendinopathy.

Bioinductive Collagen Implant Augmentation for the Repair of Chronic Lower Extremity Tendinopathies: A Report of Two Cases

In this report, we present two cases of refractory chronic lower extremity tendinopathies treated with collagen bioinductive implant augmentation: a 20-year-old male football player with chronic patellar tendinopathy and a 40-year-old active female with chronic proximal hamstring tendinopathy. We demonstrate that bioaugmentation may represent an effective strategy in the surgical treatment of chronic tendinopathies. Both patients were able to return to their pre-injury activity levels at an accelerated rate.

Proposal for a Clinical Analysis of Patellar Tendon Pathologies: In Search of Efficient Therapeutic Indications

Development and advances in our understanding of basic sciences such as anatomy, biochemistry, histology, and biomechanics have led to a better knowledge of tendon injuries. Likewise, technological advances in available therapies have conditioned the rise of new therapeutic techniques, turning both diagnosis and therapeutic indications into the foundation of treatment for patellar tendon disorders. Furthermore, we often find no correlation between patellar tendon function and structure, as studied and diagnosed from images taken and referred symptoms. This statement proposes an analytic procedure that ensures a specific therapeutic goal instead of applying a specific drug or therapeutic technique, with the aim of establishing parameters that define the kind of tendinopathy clinicians see, taking into account all conditioning factors that may affect a patellar tendinopathy. These include etiological factors, systemic illnesses affecting tendons, local mechanical causes and clinical presentation, range of clinical presentations, symptom persistence, and pain location, as well as those factors described by echography, with or without the presence of neoangiogenesis and location of the pathology, and magnetic resonance imaging. Diagnosing patellar tendinopathies requires deployment of a complex and thorough assessment process for each individual case and should include all variables that basic sciences have provided. Once a diagnosis has been made, a therapeutic strategy that includes all existing variables should be established. The more precise a diagnosis is, the more selective the treatment options become.

Changes on Tendon Stiffness and Clinical Outcomes in Athletes Are Associated With Patellar Tendinopathy After Eccentric Exercise

OBJECTIVE

Eccentric exercise is commonly used as a form of loading exercise for individuals with patellar tendinopathy. This study investigated the change of mechanical properties and clinical outcomes and their interrelationships after a 12-week single-legged decline-board exercise with and without extracorporeal shockwave therapy (ESWT).

DESIGN

Randomized controlled trial.

SETTING

Outpatient clinic of a university.

PARTICIPANTS

Thirty-four male in-season athletes with patellar tendinopathy for more than 3 months were randomized into exercise and combined groups.

INTERVENTIONS

The exercise group received a 12-week single-legged decline-squat exercise, and the combined group performed an identical exercise program in addition to a weekly session of ESWT in the initial 6 weeks.

MAIN OUTCOME MEASURES

Tendon stiffness and strain were examined using ultrasonography and dynamometry. Visual analog scale and Victoria Institute of Sports Assessment-patella (VISA-p) score were used to assess pain and dysfunction. These parameters were measured at preintervention and postintervention.

RESULTS

Significant time effect but no significant group effect on the outcome measures; significant reduction in tendon stiffness (P = 0.02) and increase in tendon strain (P = 0.00); and reduction of intensity of pain (P = 0.00) and dysfunction (P = 0.00) were observed. Significant correlations between changes in tendon stiffness and VISA-p score (ρ = -0.58, P = 0.05); alteration in tendon strain, pain intensity (ρ = -0.63, P = 0.03); and VISA-p score (ρ = 0.60, P = 0.04) were detected after the exercise program.

CONCLUSIONS

Eccentric exercise-induced modulation on tendon mechanical properties and clinical symptoms are associated in athletes with patellar tendinopathy.

Exercise therapy in the treatment of tendinopathies of the lower limbs: a protocol of a systematic review

BACKGROUND

Tendinopathies are specific degenerative conditions of the tendon characterized by pain and disability. The most common tendinopathies of the lower limbs are patellar, Achilles, gluteal, and proximal tendinopathy of the hamstring muscles. Exercise therapy has been studied for the treatment of these tendinopathies; however, different types of muscle contraction, exercise, dose, and intensity are found in the literature, which can make choosing the best treatment option difficult. The purpose of this systematic review is to analyze the available evidence about the effectiveness of exercise therapy in the treatment of patients with lower limb tendinopathies and the effects of different types of exercise therapy in the treatment of these patients.

METHODS

The search strategy will be performed in the following databases: CENTRAL, MEDLINE, EMBASE, PEDro, SPORTDiscus, and CINAHL. The inclusion criteria of the studies will be randomized controlled trials with patients with one of the following tendinopathies: patellar, Achilles, gluteal, and proximal tendinopathy of the hamstring muscles. The primary outcomes will be pain and disability. The intervention will be exercise therapy, and the comparators will be different types of exercise, control groups, or any other type of intervention.

DISCUSSION

Other systematic reviews have been published about the prescription of exercise therapy in the treatment of tendinopathies of the lower limbs. However, the results of these reviews are limited to only one type of tendinopathy or specific exercise. Because some of these reviews are also outdated, this systematic review will investigate whether exercise therapy is more effective than any other type of intervention and if there is a best form of exercise therapy, considering modality, dose, and intensity, for the treatment of lower limb tendinopathies. Furthermore, this study will present data related to the sample size, recruitment period, methodological quality, and visibility of the eligible studies.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO ( CRD42018093011 ).

Quadriceps tendinopathy: a review, part 2-classification, prognosis, and treatment

Overuse injuries of the extensor mechanism of the knee are common in both athletes and non-athletes and usually occur during activities associated with repetitive loading, stress, and knee extension. Numerous reports have been published describing extensor mechanism injuries in athletes, but there is a paucity of studies that focus on quadriceps tendinopathy in the non-athlete population. In addition, there is no universally accepted classification system for tendon pathology. Therefore, we performed a comprehensive literature review of these studies. This review consists of 2 parts. In the previous part we reviewed: (I) epidemiology and (II) diagnosis of quadriceps tendinopathy in the athlete as well as the general population. In this part we discuss: (I) classification; (II) prognosis; and (III) treatment results.

Influence of loading rate and limb position on patellar tendon mechanical properties in vivo

BACKGROUND

The aims of this study were to clarify the changes of patellar tendon length during isometric knee joint extension and the double leg squat position using ultrasonography.

METHODS

The left legs of 17 healthy adults were investigated. Isometric knee extension motion was performed at three positions of knee flexion 30° (knee 30°), knee flexion 60° (knee 60°), knee flexion 90° (knee 90°), and at each limb position, 0% (0% peak torque (PT)), 40% (40% PT), 50% (50% PT), and 60% (60% PT) of the maximum knee joint extension torque were executed at random. Both double leg squat motions were randomly performed in three positions: hip flexion 30°, knee flexion 30°, ankle dorsiflexion 10° (squat 30°); hip joint flexion 60°, knee joint flexion 60°, ankle dorsiflexion 20° (squat 60°); and hip joint flexion 90°, knee joint flexion 90°, ankle dorsiflexion 30° (squat 90°). Ultrasonography was used to measure patellar tendon length.

FINDINGS

There were no significant changes in patellar tendon length and strain between knee flexion angles of 30°, 60°, and 90° in isometric knee joint extension and the double leg squat limb position.

INTERPRETATION

The loading rate and limb position do not appear to affect the length and strain of the patellar tendon.

Arthroscopic patellar release allows timely return to performance in professional and amateur athletes with chronic patellar tendinopathy

PURPOSE

Return to sports rates in amateur and professional athletes with chronic patellar tendinopathy following arthroscopic patellar release are unpredictable. The present study aims to analyse the effectiveness of arthroscopic patellar release in professional compared to amateur athletes.

METHODS

A total of 34 amateur and 20 professional athletes with chronic patellar tendinopathy, refractory to conservative treatment, were studied prospectively and underwent arthroscopic tendon release at the inferior patellar pole. Impact of grouped sports on clinical and functional outcome, subjective patient satisfaction and return to sports rates were assessed. Additionally, preoperative MRI-scans of the knee were evaluated and correlated with clinical outcome.

RESULTS

In 40 patients (74.1%) arthroscopic patellar release resulted in complete recovery and return to preinjury exercise levels. Full return to sports was achieved after a median of 3.0 (range 0.5-12.0) months. Functional outcome measures VISA-P (Victorian Institute of sport assessment for patella) and modified Blazina scores improved significantly from pre- to postoperatively (VISA-P: 48.8 vs. 94.0 pts., respectively, p < 0.0001; Blazina: 4.47 vs. 0.5, respectively, p < 0.0001).

CONCLUSION

As rapid recovery and timely return to sports are crucial for professional athletes, arthroscopic patellar release should be considered after failed conservative treatment.

LEVEL OF EVIDENCE

IV.

Proposing a Patellar Tendinopathy Screening tool following a systematic review

BACKGROUND

Patellar tendinopathy (PT) is an overuse injury of the knee. The mechanism of injury is associated with repetitive stress on the patellar tendon of the knee as a result of explosive movement. Patellar tendinopathy is prevalent in all populations and is associated with intrinsic and extrinsic risk factors.

OBJECTIVES

Primarily, the objective was to report on the intrinsic and extrinsic risk factors for PT, entailing a systematic review of the literature; the secondary objective was to use these risk factors to compile a proposed PT screening tool from the review and standard outcome measures.

METHOD

A systematic review was undertaken according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Elimination criteria of the articles included duplicates, titles, abstracts and methodological quality. The evidence was collected, characterised with regard to the intrinsic and extrinsic risk factors and summarised descriptively.

RESULTS

The search yielded 157 feasible articles prior to commencement of article elimination. Six articles were included with a mean methodological quality score of 69%. Eight intrinsic and five extrinsic risk factors were identified. These identified risk factors are all relevant to the pathology and formed the basis for a proposed PT screening tool. The Victorian Institute of Sports Assessment for Patellar Tendinopathy Questionnaire, Visual Analog Scale and the Pain Provocation Test are also included in the proposed test.

CONCLUSION

Intrinsic and extrinsic risk factors for PT were identified, and consequently, the proposed PT screening tool was formulated for possible future testing in appropriate studies.

CLINICAL IMPLICATIONS

Prevention of PT through intrinsic and extrinsic risk factor identification, and implementation in the clinical setup as a possible outcome measurement tool with which to verify functional improvement in PT rehabilitation.

Current trends in tendinopathy: consensus of the ESSKA basic science committee. Part I: biology, biomechanics, anatomy and an exercise-based approach

Chronic tendinopathies represent a major problem in the clinical practice of sports orthopaedic surgeons, sports doctors and other health professionals involved in the treatment of athletes and patients that perform repetitive actions. The lack of consensus relative to the diagnostic tools and treatment modalities represents a management dilemma for these professionals. With this review, the purpose of the ESSKA Basic Science Committee is to establish guidelines for understanding, diagnosing and treating this complex pathology.

Arthroscopic patellar release for treatment of chronic symptomatic patellar tendinopathy: long-term outcome and influential factors in an athletic population

BACKGROUND

Arthroscopic patellar release (APR) is utilized for minimally invasive surgical treatment of patellar tendinopathy. Evidence regarding long-term success following the procedure is limited. Also, the influence of age and preoperative performance level, are incompletely understood. The aim of this study was to investigate whether APR translates into sustained pain relief over a long-term follow-up in athletes undergoing APR. Furthermore, we analyzed if age influences clinical and functional outcome measures in APR.

METHODS

Between 1998 and 2010, 30 competitive and recreational athletes were treated with APR due to chronic refractory patellar tendinopathy. All data were analyzed retrospectively. Demographic data, such as age or level of performance prior to injury were extracted. Clinical as well as functional outcome measures (Swedish Victorian Institute of sport assessment for patella (VISA-P), the modified Blazina score, pain level following exercise, return to sports, and subjective knee function were assessed pre- and postoperatively.

RESULTS

In total, 30 athletes were included in this study. At follow-up (8.8 ± 2.82 years), clinical and functional outcome measures such as the mean Blazina score, VISA-P, VAS, and subjective knee function revealed significant improvement compared to before surgery (P < 0.001). The mean time required for return to sports was 4.03 ± 3.18 months. After stratification by age, patients younger than 30 years of age yielded superior outcome in the mean Blazina score and pain level when compared to patients ≥30 years (P = 0.0448). At 8 years of follow-up, patients yielded equivalent clinical and functional outcome scores compared to our previous investigation after four years following APR.

CONCLUSION

In summary, APR can be regarded a successful, minimally invasive, and sustained surgical technique for the treatment of patella tendinopathy in athletes. Younger age at surgery may be associated with improved clinical and functional outcome following APR.

Arthroscopic treatment for calcific tendinitis; a case report

Calcific tendinitis is a common cause of shoulder pain, peaking in the fourth and fifth decades of life. The excruciate pain; especially during the night is the symptom who brings patient to the doctor. In many cases conservative treatment is the best choice. Sometimes it doesn’t work and is necessary operative treatment. It is presented a case of 60 years old women who had calcific tendinits for several years and accused pain few months with absence of improvement after conservative treatment. The patient was treated surgically with removal of calcium deposit arthroscopically. After surgery, pain relief was dramatic and movement increased rapidly. Results were very good with no complications. As a conclusion, arthroscopic evacuation of calcific deposit could be considered the best solution for patients whose symptomatology fail to improve after conservative treatment.

Anatomical study of the inferior patellar pole and patellar tendon

In this study, detailed investigations into the shape of the inferior patellar pole, the site of the patellar tendon attachment, and the length and course of the patellar tendon were performed with the aim of examining the anatomical factors involved in the developmental mechanism of patellar tendinitis. The investigation examined 100 legs from 50 cadavers. The inferior patellar pole was classified into three types: pointed, intermediate, and blunt. The attachment of the patellar tendon to the inferior patellar pole was classified into two types: an anterior and a posterior. The length of the patellar tendon was measured from the tibial tuberosity to the inferior patellar pole. The pointed type was seen in 57% of legs, the intermediate type in 21%, and the blunt type in 22%. Twenty-one legs were the pointed type, as well as the anterior type. The patellar tendon was significantly shorter with the posterior type than with the anterior type. The blunt type also had a significantly shorter patellar tendon than the pointed type. In legs that were both the pointed type and the anterior type, the inferior patellar pole and the proximal posterior surface of the patellar tendon impinged during knee flexion due to the posterior tilt of the patella, suggesting the possibility that this may induce damage. With the posterior type and blunt type, on the other hand, the possibility of strong tensile stress on the tendon fibers of the posterior facet of the inferior patellar pole was suggested.

Open Patellar Tendon Tenotomy and Debridement Combined with Suture-bridging Double-row Technique for Severe Patellar Tendinopathy

OBJECTIVE

To create a new surgical procedure for chronic severe patellar tendinopathy and to evaluate its clinical efficacy.

METHODS

In this retrospective study, the data of 12 patients with severe patellar tendinopathy in 14 knees who had undergone surgical treatment at Beijing Chao-Yang Hospital between 1 March 2009 and 1 August 2013 were analyzed. Inclusion criteria included severe patellar tendinopathy (Phase III), conservative therapy for more than 6 months, American Society of Anesthesiology status Grade I-II, and body mass index <30. Patients with severe osteoporosis, complete tendon disruption (Phase IV) and those who were unable to cooperate were excluded. There were 8 men (10 knees) and 4 women (4 knees) cases. The patients' ages ranged from 38 to 54 years (mean, 45.3 years). All surgeries had been performed by the same physician. Surgical treatment comprised incising open patellar midline tenotomy, complete debridement and suture-bridging double-row fixation. Isotonic and kinetic chain exercises were implemented after the second post-operative week. A gradual increase to full weight-bearing was allowed after the third post-operative week and a gradual return to unrestricted use of the leg after the eighth post-operative week. Preoperative and postoperative visual analogue scale (VAS) scores and Lysholm knee scores were obtained from the medical records or at recent postoperative follow-up visits and the results compared using Student's two-tailed paired t-test.

RESULTS

VAS scores decreased by a mean of 6.7 points (range, 1.1-7.8 points) during follow-up (minimum duration 14 months; range, 14-44 months) and Lysholm scores increased from 55.7 ± 6.5 points to 90.4 ± 6.2 points. Three cases (4 knees) achieved excellent outcomes (≥95 points) and 9 cases (10 knees) good outcomes (range, 86-94 points). No intraoperative or postoperative complications occurred. There were significant differences between preoperative and postoperative VAS and Lysholm scores (P < 0.01).

CONCLUSIONS

All study patients achieved good or excellent outcomes. No patellar tendon rupture or suture fixation failure occurred during follow-up. Suture-bridging double-row fixation is a simple and reliable method that not only improves patients' clinical symptoms, but also restores knee joint function.

The Value of Visa-Score and Colour Flow Imaging in the Follow-Up of Non-Athletes Operated for Jumpers Knee

The objective of this study was to assess if the Victorian Institute of Sport Assessment (VISA) questionnaire was suitable in the evaluation of patients from a mixed population with normal levels of sports activity, and if neovascularization of the patellar tendon demonstrated by color flow imaging (CFI) was more frequent in patients with lasting symptoms after surgical treatment for jumpers knee (JK). This study was conducted at St. Olavs Hospital, University Hospital of Trondheim, Norway, and included 21 men and 18 women who were operated for JK. Symptoms were assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and VISA questionnaires. Clinical and ultrasonographic examinations of the knees, including CFI, were done at a mean follow-up duration of 82 (range, 16-136) months after surgery. Patients with positive CFI also had significantly lower KOOS scores, whereas the total VISA-P (Victorian Institute of Sport Assessment - Patella) score showed no association. Patients with a positive clinical examination had significantly more frequent positive CFI findings than did patients with negative examinations. The operated patellar tendon was significantly thicker and had more frequent hypoechoic signal in the proximal part than the contralateral unoperated tendon. The post-operative VISA-P score seems less valuable in the evaluation of patients from a mixed population with normal levels of sports activity. CFI may be a valuable diagnostic tool in the evaluation of patients operated for JK.

Interventional articular and para-articular knee procedures

The knee is a common area of the body to undergo interventional procedures. This article discusses image-guided interventional issues specific to the knee area. The soft tissues in and around the knee are frequently affected by sport-related injuries and often need image-guided intervention. This article details the specific technical issues related to intervention in these soft tissues, including the iliotibial tract, fat pads, patellar tendon and other tendons, bursae and the meniscus. Most often, simple procedures such as injection and aspiration are performed without image guidance. Rarely image-guided diagnostic arthrography and therapeutic joint injections are necessary. The technique, indications and diagnostic considerations for arthrography are discussed in this article. Primary bone and soft-tissue tumours may involve the knee and adjacent soft tissues. Image-guided biopsies are frequently necessary for these lesions; this article details the technical issues related to image-guided biopsy around the knee. A number of newer ablation treatments are now available, including cryoablation, high-frequency ultrasound and microwave ablation. Radiofrequency ablation, however, still remains the most commonly employed ablation technique. The indications, technical and therapeutic considerations related to the application of this technique around the knee are discussed here. Finally, we briefly discuss some newer, but as of yet, unproven image-guided interventions for osteochondral lesions and Brodie's abscess.

Patellar tendinopathy: late-stage results from surgical treatment

Objective

To evaluate the late-stage results from surgical treatment of patellar tendinopathy (PT), using the Visa score (Victorian Institute of Sport Tendon Study Group) and the Verheyden method.

Methods

This was a retrospective study in which the postoperative results from 12 patients (14 knees) who were operated between July 2002 and February 2011 were evaluated. The patients included in the study presented patellar tendinopathy that was refractory to conservative treatment, without any other concomitant lesions. Patients who were not properly followed up during the postoperative period were excluded.

Results

Using the Verheyden method, nine patients were considered to have very good results, two had good results and one had poor results. In relation to Visa, the mean was 92.4 points and only two patients had scores less than 70 points (66 and 55 points).

Conclusion

When surgical treatment for patellar tendinopathy is correctly indicated, it has good long-term results.

Platelet-Rich Plasma in the Treatment of Patellar Tendinopathy: A Systematic Review

BACKGROUND

Patellar tendinopathy (PT) is a major cause of morbidity in both high-level and recreational athletes. While there is good evidence for the effectiveness of eccentric exercise regimens in its treatment, a large proportion of patients have disease that is refractory to such treatments. This has led to the development of novel techniques, including platelet-rich plasma (PRP) injection, which aims to stimulate a normal healing response within the abnormal patellar tendon. However, little evidence exists at present to support its use.

PURPOSE

To determine the safety and effectiveness of PRP in the treatment of PT and to quantify its effectiveness relative to other therapies for PT.

STUDY DESIGN

Systematic review.

METHODS

A systematic review was conducted in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. A literature review was conducted of the Medline, EMBASE, and Cochrane databases as well as trial registries. Both single-arm and comparative studies were included. The outcomes of interest were pain (as measured by visual analog or other, comparable scoring systems), functional scores, and return to sport. Study quality and risk of bias were assessed using the methodological index for nonrandomized studies (MINORS) score and the Cochrane risk of bias tool.

RESULTS

Eleven studies fit the inclusion criteria. Of these, 2 were randomized, controlled trials (RCTs), and 1 was a prospective, nonrandomized cohort study. The remainder were single-arm case series. All noncomparative studies demonstrated a significant improvement in pain and function after PRP injection. Complications and adverse outcomes were rare. The results of the comparative studies were inconsistent, and superiority of PRP over control treatments could not be conclusively demonstrated.

CONCLUSION

Platelet-rich plasma is a safe and promising therapy in the treatment of recalcitrant PT. However, its superiority over other treatments such as physical therapy remains unproven. Further RCTs are required to determine the relative effectiveness of the many available treatments for PT and to determine the subgroups of patients who stand to gain the most from the use of these therapies.

Analysis of muscle activations in lower extremities muscles at various angles of ankle flexion using wedges during static squat exercise

[Purpose] This study aimed to investigate changes in activation of the rectus femoris, biceps femoris, tibialis anterior, and gastrocnemius muscles during one-legged squats performed at various angles of ankle flexion. With the use of wedges, the muscles were activated at different angles of ankle flexion angles to establish the appropriate posture necessary for muscle strengthening and rehabilitation. [Subjects and Methods] Healthy adults aged 20–40 years were recruited from Good Morning Hospital in Ulsan City. Of the 22 participants, two dropped out during the tests, leaving a final sample of 20 participants. The wedges were 100 mm wide and 200 mm long and had inclinations of 10°, 30°, and 50°. EMG Analyzer software was used to measure muscle activation. [Results] A significant difference in the activation of the rectus femoris muscle at various angles of ankle flexion was seen. The gastrocnemius muscle exhibited significant differences in activation among the 0°–30°, 0°–50°, and 10°–50° inclinations. [Conclusion] Wedge-assisted muscle activation under different ankle flexion angles can be introduced as an effective exercise option under clinical conditions.

Effectiveness of extracorporeal shockwave therapy in three major tendon diseases

BACKGROUND

Extracorporeal shockwave therapy is a conservative treatment for several painful musculoskeletal disorders. The aim of the study was the assessment of the relief from pain by the shockwave therapy in a population of consecutive patients affected by specific pathologies.

MATERIALS AND METHODS

A group of consecutive patients were studied and treated. They were affected by calcific tendonitis of the shoulder (129 patients), chronic Achilles tendinopathy (102 patients), and lateral epicondylitis of the elbow (80 subjects). Each patient had 3 applications with a monthly interval, and was followed up at 1, 6, and 12 months after treatment. Results were evaluated by the numeric rating scale (NRS) in all cases, the Constant Murley Score for the assessment of the shoulder function, the American Orthopaedic Foot and Ankle Society Score for subjects affected by chronic Achilles tendinopathy, and the Oxford Elbow Score for those affected by a lateral epicondylitis of the elbow.

RESULTS

One year after treatment, the results were considered satisfactory with an almost complete resolution of symptoms. There were statistically significant results at the 12-month follow-ups regarding the mean NRS score (from 6.25 to 0.2), the Constant Murley Score (from 66.7 to 79.4), the Oxford Elbow Score (from 28 to 46), and the AOFAS (from 71 to 86).

CONCLUSIONS

Extracorporeal shockwave therapy may be considered a safe, economic, and effective treatment for several chronic musculoskeletal disorders, allowing satisfactory pain relief and improvement of function ability.

LEVEL OF EVIDENCE

Level IV.

Clinical applications of platelet-rich plasma in patellar tendinopathy

Platelet-rich plasma (PRP), a blood derivative with high concentrations of platelets, has been found to have high levels of autologous growth factors (GFs), such as transforming growth factor-β (TGF-β), platelet-derived growth factor (PDGF), fibroblastic growth factor (FGF), vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF). These GFs and other biological active proteins of PRP can promote tissue healing through the regulation of fibrosis and angiogenesis. Moreover, PRP is considered to be safe due to its autologous nature and long-term usage without any reported major complications. Therefore, PRP therapy could be an option in treating overused tendon damage such as chronic tendinopathy. Here, we present a systematic review highlighting the clinical effectiveness of PRP injection therapy in patellar tendinopathy, which is a major cause of athletes to retire from their respective careers.

High volume image-guided Injections for patellar tendinopathy: a combined retrospective and prospective case series

BACKGROUND

the aim was to quantify the effect of a novel high volume-image guided injection (HVIGI) technique for recalcitrant patellar tendinopathy (PT).

METHODS

twenty patients (8 prospective; 12 retrospective) with ultrasonographically confirmed proximal PT were recruited. A HVIGI under ultra-sound guidance of 10 ml 0.5% Bupivacaine, 25 mg Hydrocortisone and 30 ml normal saline at the interface of the patellar tendon and Hoffa's fat pad was administered. A standardised eccentric loading rehabilitation protocol was prescribed.

RESULTS

the VISA-P score improved from 45.0 to 64.0 (p<0.01) for all subjects, likely to be clinically significant. There was no statistically significant difference between the increase in the retrospective group of 19.9 (± 23.5) and the prospective of 16.4 (± 11.3) p = 0.7262.5% of prospective subjects agreed that they had significantly improved, with 37.5% returning to sport within 12 weeks.

CONCLUSIONS

HVIGI should be considered in the management of recalcitrant PT. Randomised controlled trials are warranted.

In vivo evaluation of the elastic anisotropy of the human Achilles tendon using shear wave dispersion analysis

Non-invasive evaluation of the Achilles tendon elastic properties may enhance diagnosis of tendon injury and the assessment of recovery treatments. Shear wave elastography has shown to be a powerful tool to estimate tissue mechanical properties. However, its applicability to quantitatively evaluate tendon stiffness is limited by the understanding of the physics on the shear wave propagation in such a complex medium. First, tendon tissue is transverse isotropic. Second, tendons are characterized by a marked stiffness in the 400 to 1300 kPa range (i.e. fast shear waves). Hence, the shear wavelengths are greater than the tendon thickness leading to guided wave propagation. Thus, to better understand shear wave propagation in tendons and consequently to properly estimate its mechanical properties, a dispersion analysis is required. In this study, shear wave velocity dispersion was measured in vivo in ten Achilles tendons parallel and perpendicular to the tendon fibre orientation. By modelling the tendon as a transverse isotropic viscoelastic plate immersed in fluid it was possible to fully describe the experimental data (deviation<1.4%). We show that parallel to fibres the shear wave velocity dispersion is not influenced by viscosity, while it is perpendicularly to fibres. Elasticity (found to be in the range from 473 to 1537 kPa) and viscosity (found to be in the range from 1.7 to 4 Pa.s) values were retrieved from the model in good agreement with reported results.