Jumper's knee

Bi-Exponential 3D UTE-T1ρ Relaxation Mapping of Ex Vivo Human Knee Patellar Tendon at 3T

Introduction: The objective of this study was to assess the bi-exponential relaxation times and fractions of the short and long components of the human patellar tendon ex vivo using three-dimensional ultrashort echo time T1ρ (3D UTE-T1ρ) imaging. Materials and Methods: Five cadaveric human knee specimens were scanned using a 3D UTE-T1ρ imaging sequence on a 3T MR scanner. A series of 3D UTE-T1ρ images were acquired and fitted using single-component and bi-component models. Single-component exponential fitting was performed to measure the UTE-T1ρ value of the patellar tendon. Bi-component analysis was performed to measure the short and long UTE-T1ρ values and fractions. Results: The single-component analysis showed a mean single-component UTE-T1ρ value of 8.4 ± 1.7 ms for the five knee patellar tendon samples. Improved fitting was achieved with bi-component analysis, which showed a mean short UTE-T1ρ value of 5.5 ± 0.8 ms with a fraction of 77.6 ± 4.8%, and a mean long UTE-T1ρ value of 27.4 ± 3.8 ms with a fraction of 22.4 ± 4.8%. Conclusion: The 3D UTE-T1ρ sequence can detect the single- and bi-exponential decay in the patellar tendon. Bi-component fitting was superior to single-component fitting.

Surgical treatment of chronic proximal patellar tendon tears grades 3 and 4 using augmentation with quadriceps tendon-bone graft

BACKGROUND

Chronic proximal patellar tendinosis with partial tendon tears represents a multifactorial overuse injury. Several surgical techniques have been described with various outcomes and the return to sports may fail.

HYPOTHESIS

Reconstruction of the proximal patellar tendon with augmentation using a quadriceps tendon-bone (QTB) graft improves knee function in patients presenting with proximal patellar tendinosis and partial tendon tears.

METHODS

Forty-seven patients (32 males, 15 females) with chronic proximal patellar tendinosis and tendon tears grade 3 and 4 were treated between 1992 and 2018. Patients were evaluated retrospectively using the Popkin-Golman (PG) MRI grading system and the removed tendon parts. The Tegner Activity Scale (TAS) and the Numerical Rating Scale (NRS) for pain were used as outcome measures before surgery and at follow up. Complete data were available in 100% of cases at 6 months follow up, and fifteen of them at later follow up.

RESULTS

The average follow up was 1.5 years (range, 0.5-16). The TAS improved from a mean preoperative score of 3.7 to a mean postoperative score of 9.1. The median NRS status decreased from an average of 6.4 to 1.1. Two patients needed additional arthroscopic scar tissue removal.

CONCLUSION

Reconstruction of proximal patellar tendon tears grades 3 and 4 with augmentation using a QTB graft is a valuable surgical salvage procedure in chronic cases. It improves knee function and yields good to excellent results in most cases including high level athletes. The use of MRI with the PG classification of tendon tears is highly recommended.

LEVEL OF EVIDENCE

Therapeutic case series, Level IV.

Current Concepts in Patellar Tendinopathy: An Overview of Imaging, Pathogenesis, and Nonoperative and Operative Management

» Approximately 1 in 3 high-impact athletes develops patellar tendinopathy (PT), with the proximal insertion of the patellar tendon being the most commonly affected anatomical site.» Nonoperative treatment options are effective in reducing pain and restoring functionality in most patients with PT. However, operative intervention should be considered when conservative management fails.» A comprehensive review of the literature on surgical procedures, including both open and arthroscopic approaches, was conducted with a specific focus on clinical outcomes and return to sports.» Both open surgery and arthroscopic surgery for PT have demonstrated favorable success rates and return-to-sport outcomes, with arthroscopic treatment potentially expediting the recovery process.

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.

Knee dynamics during take-off and landing in spike jumps performed by volleyball players with patellar tendinopathy

[Purpose] Patellar tendinopathy is a common sports injury. The risk factors for this injury can be categorized as intrinsic, extrinsic, and dynamic. We examined the dynamic factors in this study. [Participants and Methods] The participants were volleyball players who were assigned to a patient group (n=6) if they had medial patellar tendinopathy in the left knee or to a control group (n=7) otherwise. The participants performed spike jumps, and their ground reaction force and three-dimensional kinematic data were recorded. Knee angle and moment data were extracted at the peak extension moment of take-off and landing. [Results] The two groups showed no differences in knee angles. A tendency for abduction/external rotation moments at take-off and landing on both sides was observed in the control group, while the patient group showed adduction and internal rotation moments at take-off and adduction moment at landing in the left (injured) knee. [Conclusion] The observed knee joint moments in the left (injured) knee of the patient group may have been involved in the pathophysiological mechanism underlying the development of patellar tendinopathy.

Comparison Between Ultrasonography and Magnetic Resonance Imaging in Achilles Tendon

Purpose: This study aims was to compared the effectiveness of Magnetic Resonance Imaging (MRI) and Ultrasonography (US) imaging techniques in the diagnosis of tendon pathology. Method: The databases search of PubMed, Scopus, and Embase extracted 567 articles for a title and abstract review. After removing and evaluating, a total of 6 articles were collected. Results and conclusion: There are three views on the diagnosis of Achilles tendon (AT) by US and MRI: US has higher sensitivity and reliability than MRI; MRI is more effective than the US, and there is a similar diagnosis result between US and MRI. It may not be necessary to distinguish between the diagnostic role of US and MRI, since US and MRI tools can be used as effective means to provide valuable information for the diagnosis and treatment of AT.

Failed Surgery for Patellar Tendinopathy in Athletes: Midterm Results of Further Surgical Management

Background:

Tendon injuries are commonly seen in sports medicine practice. Many elite players involved in high-impact activities develop patellar tendinopathy (PT) symptoms. Of them, a small percentage will develop refractory PT and need to undergo surgery. In some of these patients, surgery does not resolve these symptoms.

Purpose:

To report the clinical results in a cohort of athletes who underwent further surgery after failure of primary surgery for PT.

Study Design:

Case series; Level of evidence, 4.

Methods:

A total of 22 athletes who had undergone revision surgery for failed surgical management of PT were enrolled in the present study. Symptom severity was assessed through the Victorian Institute of Sport Assessment Scale for Patellar Tendinopathy (VISA-P) upon admission and at the final follow-up. Time to return to training, time to return to competition, and complications were also recorded.

Results:

The mean age of the athletes was 25.4 years, and the mean symptom duration from the index intervention was 15.3 months. At a mean follow-up of 30.0 ± 4.9 months, the VISA-P score improved 27.8 points (P < .0001). The patients returned to training within a mean of 9.2 months. Fifteen patients (68.2%) returned to competition within a mean of 11.6 months. Of these 15 patients, a further 2 had decreased their performance, and 2 more had abandoned sports participation by the final follow-up. The overall rate of complications was 18.2%. One patient (4.5%) had a further revision procedure.

Conclusion:

Revision surgery was feasible and effective in patients in whom PT symptoms persisted after previous surgery for PT, achieving a statistically significant and clinically relevant improvement of the VISA-P score as well as an acceptable rate of return to sport at a follow-up of 30 months.

The Influence of Specific Bioactive Collagen Peptides on Knee Joint Discomfort in Young Physically Active Adults: A Randomized Controlled Trial

First evidence indicates that the supplementation of specific collagen peptides is associated with a significant reduction in activity-related joint pain in young adults. The purpose of the current investigation was to confirm the efficacy of the same collagen peptides in a comparable study population. In total, 180 active men and women aged between 18 and 30 years with exercise-related knee pain but no diagnosed joint disease completed the trial over a period of 12 weeks. Participants were randomly assigned to the group receiving 5 g of specific collagen peptides (CP-G) or to the placebo group (P-G). For the primary outcome, changes in pain during or after exercise from pre- to post-intervention were assessed by the participants using the Visual Analog Scale (VAS). These changes were additionally evaluated by the examining physician by means of anamnesis and physical examination of the affected knee joint. As secondary outcomes, pain under resting conditions and after 20 squats were compared between the study groups. In addition, the mobility of the knee joint and the use of alternative therapies (e.g., ointments or physiotherapy) were recorded. The supplementation of specific collagen peptides derived from type I collagen with a mean molecular weight of 3 kDa led to a significantly (p = 0.024) higher reduction of exercise-induced knee pain (−21.9 ± 18.3 mm) compared with the placebo group (−15.6 ± 18.5 mm). These findings were consistent with the physician’s evaluation (−23.0 ± 19.2 mm vs. −14.6 ± 17.9 mm, p = 0.003). The decrease in pain under resting conditions and after squats did not significantly differ between the groups, as only a small number of participants suffered from pain under these conditions. Due to the clinically unremarkable baseline values, the mobility of the knee joint did not change significantly after the intervention. In conclusion, the current investigation confirmed that the oral intake of bioactive collagen peptides used in the current investigation led to a statistically significant reduction of activity-related joint pain in young active adults suffering from knee joint discomfort.

Knee cartilage damage and concomitant internal derangement on MRI in athletes competing at the Rio de Janeiro 2016 Summer Olympics

•

Cartilage damage is frequently observed on MRI in Olympic Athletes.

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Patellofemoral cartilage damage is most common and associated with certain sports including volleyball and weightlifting.

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Meniscal tears are associated with localized cartilage damage.

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Trend for prevalence of cartilage damage to increase with increasing age of the athlete.

Purpose

To report the MRI patterns of knee cartilage damage and concomitant internal derangement in athletes participating at the Rio de Janeiro 2016 Olympic Games.

Methods

Knee MRIs obtained at the core imaging facility of the International Olympic Committee were blindly, retrospectively reviewed by a board-certified musculoskeletal radiologist for meniscal, ligamentous, and tendon abnormalities. Cartilage assessment was based on the modified Outerbridge criteria.

Results

Of 122 athletes who received a knee MRI, 64 (52.4 %) had cartilage damage. Cartilage damage was more prevalent in the patellofemoral compartment (52 athletes, 42.6 %), followed by lateral (23 athletes, 18.9 %) and medial tibiofemoral compartments (12 athletes, 9.8 %). Patellofemoral cartilage damage was most prevalent in beach-volleyball (100 %), followed by volleyball (8 athletes, 66.7 %) and weightlifting (7 athletes, 70 %). Patellofemoral cartilage damage was most prevalent with quadriceps (8 athletes, 72.7 %) and patellar tendinosis (11 athletes, 61.1 %). Medial and lateral tibiofemoral cartilage damage was significantly associated with medial (8 athletes, 29.6 %) and lateral meniscal tears (16 athletes, 55.2 %), respectively. There was a trend for the percentage of athletes with cartilage damage to increase with age.

Conclusion

The majority of athletes at the 2016 Rio Summer Olympics who had a knee MRI showed cartilage damage. Patellofemoral compartment cartilage damage was most common and frequently observed in certain sports including volleyball, beach volleyball, and weightlifting. Overuse in these sports can contribute to patellofemoral cartilage damage and subsequent development of anterior knee pain. Cartilage damage was also observed with concomitant meniscal tears and older age.

Management of Achilles and patellar tendinopathy: what we know, what we can do

Tendinopathies are challenging conditions frequent in athletes and in middle-aged overweight patients with no history of increased physical activity. The term “tendinopathy” refers to a clinical condition characterised by pain, swelling, and functional limitations of tendons and nearby structures, the effect of chronic failure of healing response. Tendinopathies give rise to significant morbidity, and, at present, only limited scientifically proven management modalities exist. Achilles and patellar tendons are among the most vulnerable tendons, and among the most frequent lower extremity overuse injuries. Achilles and patellar tendinopathies can be managed primarily conservatively, obtaining good results and clinical outcomes, but, when this approach fails, surgery should be considered. Several surgical procedures have been described for both conditions, and, if performed well, they lead to a relatively high rate of success with few complications. The purpose of this narrative review is to critically examine the recent available scientific literature to provide evidence-based opinions on these two common and troublesome conditions.

Comparative Effectiveness of Different Nonsurgical Treatments for Patellar Tendinopathy: A Systematic Review and Network Meta-analysis

PURPOSE

To investigate the functional improvement and pain reduction of different nonsurgical treatments for patellar tendinopathy (PT), a systematic review with network meta-analysis was performed.

METHODS

Studies were comprehensively searched for without language restrictions in the CENTRAL, MEDLINE, EMBASE, Web of Science, Physiotherapy Evidence Database, and SPORTDiscus databases from inception to May 2018. Randomized controlled trials about nonsurgical treatments for PT were included. The outcome measurements were the Victorian Institute of Sports Assessment (VISA) scale and pain scores (such as the visual analog scale or Numerical Rating Scale). Study quality was evaluated using the Physiotherapy Evidence Database score. Direct comparisons were performed using pairwise meta-analysis, whereas network meta-analysis was performed using a frequentist method in a multivariate random-effects model.

RESULTS

Eleven studies with 430 affected patellar tendons were included in the systematic review. The summary mean difference of improvement in the VISA scale versus the control group for corticosteroid injection was -23.00 (95% confidence interval [CI] -36.73 to -9.27), for leukocyte-rich platelet-rich plasma (LR-PRP) was 13.22 (95% CI 2.37-24.07), for focused extracorporeal shockwave therapy (ESWT) was -1.28 (95% CI -6.25 to 3.68), for radial ESWT was -6.68 (95% CI -20.20 to 6.84), for ultrasound was -0.70 (95% CI -11.23 to 9.83), for autologous blood injection was -0.60 (95% CI -9.30 to 8.10), for dry needling was 17.51 (95% CI -2.57 to 37.60), for topical glyceryl trinitrate was -0.90 (95% CI -13.07 to 11.27), and for skin-derived tendon-like cells was 10.40 (95% CI -1.59 to 22.39). LR-PRP (Surface Under the Cumulative Ranking curve [SUCRA] = 87.5%) or dry needling (SUCRA = 90.5%) was most likely to be ranked the best in terms of improvement on the VISA scale. Compared with the control group, the summary mean difference of the change in pain score for corticosteroid injection was 0.80 (95% CI -3.48 to 5.08), for LR-PRP was -1.87 (95% CI -3.28 to -0.46), for focused ESWT was 0.13 (95% CI -0.68 to 0.93), for radial ESWT was 0.03 (95% CI -1.92 to 1.98), for ultrasound was -0.20 (95% CI -1.49 to 1.09), for autologous blood injection was 0.60 (95% CI -0.73 to 1.93), for dry needling was -0.37 (95% CI -2.71 to 1.97), and for topical glyceryl trinitrate was -0.50 (95% CI -2.55 to 1.55). The treatment most likely to be ranked the best in terms of change in pain score was LR-PRP (SUCRA = 94.9%).

CONCLUSIONS

The network meta-analysis demonstrated that LR-PRP has the greatest functional improvement and pain reduction for PT compared with other treatment options. However, the treatment effect estimates can be biased by the possible intransitivity and should not be overestimated.

LEVEL OF EVIDENCE

Level I, meta-analysis of Level I studies.

Inter- and intra-rater reliability of ultrasound tissue characterization (UTC) in patellar tendons

PURPOSE

Ultrasound tissue characterization (UTC) is used in research and clinical practice to quantify tendon structure of the patellar tendon. This is the first study to investigate the inter- and intra-rater reliability for UTC of the patellar tendon on a large scale.

METHOD

Fifty participants (25 patellar tendinopathy, 25 asymptomatic) were recruited. The affected patellar tendons in symptomatic and right tendons in asymptomatic participants were scanned with UTC twice by one researcher and once by another. The same was done for contour marking (needed to analyze a UTC scan) of the tendon. Intraclass correlation coefficient (ICC (2,1)) for echo-types I, II, III, IV, aligned fibrillar structure (echo-types I + II), and disorganized structure (echo-types III + IV) were calculated. This was done for UTC scans as well as solely marking contours.

RESULTS

Inter-rater reliability showed fair to good ICC values for echo-types I (0.65) and II (0.46) and excellent ICC values for echo-type III (0.81), echo-type IV (0.83), aligned fibrillar structure (0.82), and disorganized structure (0.82). Intra-rater reliability showed excellent ICC values for echo-types I (0.76), III (0.88), IV (0.85), aligned fibrillar structure (0.88), and disorganized fibrillar structure (0.88) and a fair to good value for echo-type II (0.61). Contour marking showed excellent ICC values for all echo-types.

CONCLUSION

This study showed that UTC scans for patellar tendons have overall good intra-rater and inter-rater reliability. To optimize reliability of UTC scans of the patellar tendon, using the same rater and using aligned fibrillar structure (echo-types I + II combined) and disorganized structure (echo-types III + IV combined) as outcome measures can be considered.

Immediate effect of infrapatellar strap on pain and jump height in patellar tendinopathy among young athletes

BACKGROUND:

Infrapatellar strapping is a treatment technique used in various knee pathologies; however, its effect on pain and functional performance among young athletes has not been studied.

OBJECTIVES:

To evaluate the effect of infrapatellar strap on pain and jumping performance among young athletes diagnosed with patellar tendinopathy.

STUDY DESIGN:

Pre-/post-test (within-subject research design).

METHODS:

A total of 16 young male basketball and volleyball athletes (age range, 12-18 years) diagnosed with patellar tendinopathy were included in the study. Infrapatellar strap was applied beneath the patella, over the patellar tendon. The athletes performed four jumping tests: squat jump, drop jump, single-leg jump, and jumps 30 s test, with and without the strap. Pain severity in the symptomatic knee during jumping was assessed using a visual analog scale and jumping performance parameters were assessed using an Optojump Next optical measurement system.

RESULTS:

Pain severity reported by the participants decreased in drop test, single-leg jump test, and jumps 30 s test while using the infrapatellar strap compared with no strap condition ( p < 0.05). No significant difference in jumping performance was found between jumping with and without the strap.

CONCLUSION:

The infrapatellar strap was effective in reducing local pain among young male athletes without altered jumping performance.

CLINICAL RELEVANCE

The infrapatellar strap can be recommended to use during physical activity as part of the physical therapy treatments for patellar tendinopathy. Given the low cost, ease to use, and being a non-invasive method without adverse effects, it is an appropriate intervention for young athletes.

Treatment Options for Patellar Tendinopathy: A Systematic Review

PURPOSE

To compare the efficacy of common invasive and noninvasive patellar tendinopathy (PT) treatment strategies.

METHODS

A systematic search was performed in PubMed, Google Scholar, CINAHL, UptoDate, Cochrane Reviews, and SPORTDiscus. Fifteen studies met the following inclusion criteria: (1) therapeutic outcome trial for PT, and (2) Victorian Institute of Sports Assessment was used to assess symptom severity at follow-up. Methodological quality and reporting bias were evaluated with a modified Coleman score and Begg's and Egger's tests of bias, respectively.

RESULTS

A total of 15 studies were included. Reporting quality was high (mean Coleman score 86.0, standard deviation 9.7), and there was no systematic evidence of reporting bias. Increased duration of symptoms resulted in poorer outcomes regardless of treatment (0.9% decrease in improvement per additional month of symptoms; P = .004). Eccentric training with or without core stabilization or stretching improved symptoms (61% improvement in the Victorian Institute of Sports Assessment score, 95% confidence interval [CI] 53% to 69%). Surgery in patients refractory to nonoperative treatment also improved symptoms (57%, 95% CI 52% to 62%) with similar outcomes among arthroscopic and open approaches. Results from shockwave (54%, 95% CI 22% to 87%) and platelet-rich plasma (PRP) studies (55%, 95% CI 5% to 105%) varied widely though PRP may accelerate early recovery. Finally, steroid injection provided no benefit (20%, 95% CI -20% to 60%).

CONCLUSIONS

Initial treatment of PT can consist of eccentric squat-based therapy, shockwave, or PRP as monotherapy or an adjunct to accelerate recovery. Surgery or shockwave can be considered for patients who fail to improve after 6 months of conservative treatment. Corticosteroid therapy should not be used in the treatment of PT.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II-IV studies.

[Evidence-based therapy for tendinopathy of the knee joint : Which forms of therapy are scientifically proven?]

Tendinopathy in the region of the knee joint is a common pathological disorder. People active in sports, in particular, have a high probability of suffering from tendinopathy. Despite its high clinical relevance, the level of evidence of therapy options for tendinopathy in the knee region differs greatly. This review gives an overview of current evidence levels for therapy options in tendinopathy of the quadriceps, patellar and pes anserinus insertion tendons as well as of the distal iliotibial tract tendon. The treatment with platelet-rich plasma showed a significantly better outcome when used correctly and treatment with shock waves, operative treatment and sclerotherapy have also shown positive effects. Treatment with corticosteroid injections and with oral non-steroidal anti-inflammatory drugs (NSAID) showed positive short-term effects (follow-up ±4 weeks). No reasonable data are available for the treatment of tendinopathy in the knee region by acupuncture, fascial therapy or cryotherapy. The use of kinesio taping showed no significant relief from complaints compared with standard conservative treatment. The use of multimodal therapy without evidence is, therefore, particularly common in elite athletes.

Patellar Tendinopathy

Context:

Patellar tendinopathy is a common condition. There are a wide variety of treatment options available, the majority of which are nonoperative. No consensus exists on the optimal method of treatment.

Evidence Acquisition:

PubMed spanning 1962-2014.

Study Design:

Clinical review.

Level of Evidence:

Level 4.

Results:

The majority of cases resolve with nonoperative therapy: rest, physical therapy with eccentric exercises, cryotherapy, anti-inflammatories, corticosteroid injections, extracorporeal shockwave therapy, glyceryl trinitrate, platelet-rich plasma injections, and ultrasound-guided sclerosis. Refractory cases may require either open or arthroscopic debridement of the patellar tendon. Corticosteroid injections provide short-term pain relief but increase risk of tendon rupture. Anti-inflammatories and injectable agents have shown mixed results. Surgical treatment is effective in many refractory cases unresponsive to nonoperative modalities.

Conclusion:

Physical therapy with an eccentric exercise program is the mainstay of treatment for patellar tendinopathy. Platelet-rich plasma has demonstrated mixed results; evidence-based recommendations on its efficacy cannot be made. In the event that nonoperative treatment fails, surgical intervention has produced good to excellent outcomes in the majority of patients.

Reliability and Validity of the Korean Version VISA-P Questionnaire for Patellar Tendinopathy in Adolescent Elite Volleyball Athletes

Objective

To translate the English Victorian Institute of Sport Assessment for patellar tendinopathy (VISA-P) questionnaire into a Korean version and to determine the reliability and validity of the Korean version.

Methods

The English VISA-P questionnaire was translated into Korean according to the internationally recommended guidelines. Then, 28 adolescent elite volleyball athletes (average age, 16 years; range, 14 to 19 years) were asked to complete the questionnaire three times (before examination, after examination, and 1 week later) for reliability. They were evaluated through a physical examination and ultrasonography to diagnosis patellar tendinopathy.

Results

The internal consistency of the VISA-P questionnaire by Cronbach's alpha was 0.80 for the first, 0.78 for the second, and 0.79 for the third assessment. The intraclass correlation coefficient (ICC) between the first and second assessments was 0.97. The ICC between the second and third assessments was 0.96. The mean VISA-P scores were 67.6±15.7 for the patellar tendinopathy group (n=23) and 92.6±8.6 for the normal group (n=5). There were significantly lower VISA-P scores in the patellar tendinopathy group compared to the normal group.

Conclusion

The translated Korean version VISA-P questionnaire has good internal consistency, test-retest reliability and validity. In addition, this study indicated that most adolescent elite volleyball athletes had patellar tendon problems. Therefore, the Korean version VISA-P is a useful self-administered outcome score of athletes with patellar tendinopathy.

Eccentric Exercise Protocols for Patella Tendinopathy: Should we Really be Withdrawing Athletes from Sport? A Systematic Review

The 2007 review by Visnes and Bahr concluded that athletes with patella tendinopathy should be withdrawn from sport whilst engaging in eccentric exercise (EE) rehabilitation programs. However, deprivation of sport is associated with a number of negative psychological and physiological effects. Withdrawal from sport is therefore a decision that warrants due consideration of the risk/benefit ratio. The aim of this study was to determine whether sufficient evidence exists to warrant withdrawal of athletes from sport during an eccentric exercise rehabilitation program. A systematic review of the literature was performed to identify relevant randomised trials. Data was extracted to determine whether athletes were withdrawn from sport, what evidence was presented to support the chosen strategy and whether this affected the clinical outcome. Seven studies were included. None of these reported high quality evidence to support withdrawal. In addition, three studies were identified in which athletes were not withdrawn from sport and still benefited from EE. This review has demonstrated that there is no high quality evidence to support a strategy of withdrawal from sport in the management of patella tendinopathy.

Ultrasound-guided sclerosis of neovessels in patellar tendinopathy: a prospective study of 101 patients

BACKGROUND

A randomized controlled study has shown promising clinical results after treatment with sclerosing injections in a group of patients with patellar tendinopathy, but no study has investigated medium- or long-term outcome in a large and unselected group of patients.

PURPOSE

To investigate if sclerosing treatment would affect the level of patellar tendon pain and knee function after 24 months in a large group of patients with patellar tendinopathy.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

This prospective study recruited patients with a clinical diagnosis of jumper's knee and visible neovascularization corresponding to the painful area on power Doppler ultrasound. They received up to a maximum of 5 ultrasound-guided sclerosing injections using polidocanol at 4- to 6-week intervals. Knee pain and function were recorded using the Victorian Institute of Sport Assessment-Patella (VISA-P) score before treatment and 6, 12, and 24 months after the first injection.

RESULTS

In total, 101 patients (15 women and 86 men) with 120 tendons were included and given from 1 to 5 sclerosing injections (mean [SD], 2.5 [0.9]). The patients reported a significantly improved VISA-P score from baseline (mean, 39; 95% confidence interval [CI], 36-42) to the 24-month follow-up (mean, 65; 95% CI, 60-70) (range, 21-100; P < .001, paired t test). However, a VISA-P score of >95 points was reported in only 22 cases (20%), whereas 37 cases (36%) reported a VISA-P score of <50 at 24 months.

CONCLUSION

Sclerosing treatment with polidocanol resulted in a moderate improvement in knee function and reduced pain in a heterogeneous group of patients with patellar tendinopathy. Nevertheless, few of the patients were cured, and the majority still had reduced function and substantial pain after 24 months of follow-up.

Associations between abnormal ultrasound color Doppler measures and tendon pain symptoms in badminton players during a season: a prospective cohort study

BACKGROUND

Color Doppler ultrasound is widely used to examine intratendinous flow in individuals with overuse tendon problems, but the association between color Doppler and pain is still unclear.

HYPOTHESIS

Intratendinous flow is present and associated with pain in badminton players, and intratendinous flow and pain increase during a badminton season.

STUDY DESIGN

Cohort study (prognosis); Level of evidence, 2.

METHODS

Ninety-five semiprofessional badminton players were included in the study at a tournament at the start of the badminton season. All players were interviewed regarding pain. The anterior knee tendons and Achilles tendons were studied. Each tendon was scored using a quantitative grading system (grades 0-5) and a qualitative scoring system (color fraction) using color Doppler ultrasound. Eight months later, 86 of the players (91%) were retested by the same investigators during an equivalent badminton tournament (including 1032 tendon regions; 86 players with 4 tendons each with 3 regions), thus forming the study group.

RESULTS

At the start of the season, 24 players (28%) experienced pain in 37 tendons (11%), and at the end of the season, 31 players (36%) experienced pain in 51 tendons (15%), which was a statistically significant increase (P = .0002). Abnormal flow was found in 230 tendon regions in 71 players (83%) at the start of the season compared with 78 tendon regions in 41 players (48%) at the follow-up. The decrease in abnormal flow was statistically significant (P < .0001). Of the 37 painful tendons at the start of the season, 25 had abnormal flow (68%). In contrast, 131 tendons (85%) with abnormal flow at the start of the season were pain free. At the end of the season, 18 of the 51 painful tendons (35%) had abnormal flow. Ninety-six of the 131 pain-free tendons (73%) with abnormal flow at the start of the season were normalized (no pain and normal flow) at the end of the season.

CONCLUSION

It was not possible to verify any association between intratendinous flow and pain at the start of the season or at the follow-up (end of the season). Intratendinous flow at the start of the season could not predict symptomatic outcome at the end of the season. The decrease in Doppler flow during the season might suggest that intratendinous flow could be part of a physiological adaptive response to loading and that intratendinous flow as previously believed is not always a sign of pathological changes.

Efficacy of an inertial resistance training paradigm in the treatment of patellar tendinopathy in athletes: a case-series study

STUDY DESIGN

Case-series study with pre- vs. post-test measurements design.

BACKGROUND

Strength training programs emphasizing eccentric muscle actions have received much attention in the treatment of tendinopathies. The current study reports on the efficacy of a novel strength training paradigm using inertial eccentric-concentric resistance to treat chronic patellar tendinopathy.

CASE DESCRIPTION

Ten athletes with chronic patellar tendinopathy (15 tendons) volunteered for the study. Subjects completed a 6-week training program employing a leg press flywheel ergometer. Pre and post measurements assessed lower limb maximal strength and vertical counter-movement-jump (CMJ) height. Surface electromyography (SEMG) analysis of paraspinal, rectus femoris, biceps femoris and medial gastrocnemius muscles were collected. All measurements were performed one week before and after the training period. Clinical measures of pain and tendon function were assessed by means of a visual analogue scale (VAS) and a patellar tendinopathy questionnaire (VISA) at baseline, post-training and follow-up (12 wk). The Wilcoxon signed-rank test was employed for data comparisons.

RESULTS

Eccentric strength increased after training (90%, p < 0.05). Similarly, VAS and VISA scores improved after training as well (60% and 86%, respectively, p < 0.01). There were no changes in CMJ height.

CONCLUSION

Short-term training using inertial eccentric overload, resulted in improved muscle function and reduced subjective pain in long-lasting patellar tendinopathy.

Clinical signs and anatomical correlation of patellar tendinitis

BACKGROUND

Patellar tendinitis is one of the several differential diagnosis of anterior knee pain. The clinical diagnosis of patellar tendinitis is based on tenderness to palpation at the inferior pole of the patella. The tenderness has been noted to be maximal when the knee is extended and the quadriceps relaxed, but a definite clinical sign for diagnosis is lacking. The accuracy of two clinical signs was assesed by a two-stage study which included physical examination, MRI and a cadaveric study.

MATERIALS AND METHODS

Two clinical signs, the "passive flexion-extension sign" and the "standing active quadriceps sign" were assessed in 10 consecutive patients with presumed patellar tendinitis. Five patients had an MRI, showed focal abnormality in the tendon. The location of the MRI finding corresponded, to the region of maximal tenderness. A cadaveric dissection was undertaken to describe the anatomy of the patella and the patellar tendon during these tests.

RESULTS

Both tests showed a significant decrease in tenderness at the area of inflammation when the patellar tendon was under tension. The cadaveric dissection showed that when the knee is flexed to 90° or when the quadriceps is tensioned the deep fibers of the tendon do not deform to anteriorly applied pressure.

CONCLUSION

We suggest using these studies routinely in the evaluation of patients with anterior knee pain.

Platelet-rich plasma: new clinical application: a pilot study for treatment of jumper's knee

This study describes a simple, low-cost, minimally invasive way to apply PRP growth factors to chronic patellar tendinosis; 20 male athletes with a mean history of 20.7 months of pain received treatment, and outcomes were prospectively evaluated at 6 months follow-up. No severe adverse events were observed, and statistically significant improvements in all scores were recorded. The results suggest that this method may be safely used for the treatment of jumper's knee, by aiding the regeneration of tissue which otherwise has low healing potential.

Overload syndromes of the knee in adolescents: Sonographic findings

Overload syndromes are caused by repetitive microtrauma, and the knee joint is most frequently affected in adolescents. The reason for this is that the knee joint is engaged in almost all sports activities. Pathologies related to the anterior aspect of the knee are: femoropatellar pain, jumper's knee syndromes, Osgood-Schlatter disease, Sinding-Larsen-Johansson syndrome and patellar stress fractures; to the medial aspect: semimembranous tendon enthesopathy and pes anserinus bursitis; to the lateral aspect: iliotibial band syndrome (runner's knee), popliteus and femoral biceps tendon enthesopathy; to the posterior aspect: fabella syndrome and medial gastrocnemius muscle tendon enthesopathy. Sonography plays a central role in the diagnosis and can also evaluate the evolution of diseases. This method is well accepted by the patients and by their parents, it does not involve exposure to X-rays and it is inexpensive. US imaging should, therefore, be considered a first-line imaging diagnostic technique in functional overuse syndromes of the knee.

Knee complaints seen in general practice: active sport participants versus non-sport participants

Background

Since knee complaints are common among athletes and are frequently presented in general practice, it is of interest to investigate the type of knee complaints represented in general practice of athletes in comparison with those of non-athletes. Therefore, the aim of this study is to investigate the differences in type of knee complaints between sport participants, in this study defined as athletes, and non-sport participants, defined as non-athletes, presenting in general practice. Further, differences in the initial policy of the GP, medical consumption, and outcome at one-year follow-up were also investigated.

Methods

Patients consulting their GP for a new episode of knee complaints were invited to participate in this prospective cohort study. From the total HONEUR knee cohort population (n = 1068) we extracted patients who were athletes (n = 421) or non-athletes (n = 388).

Results

The results showed that acute distortions of the knee were significantly more diagnosed in athletes than in non-athletes (p = 0.04). Further, more athletes were advised by their GP to 'go easy on the knee' than the non-athletes (p < 0.01), but no differences were found in number of referrals and medication prescribed by the GP. The medical consumption was significantly higher among athletes; however, no significant differences were found between the two groups for recovery at one-year follow-up.

Conclusion

There are no major differences in the diagnosis and prognosis of knee complaints between athletes and non-athletes presented to the GP. This implies that there are no indications for different treatment strategies applied in both groups. However, athletes are more often advised to 'go easy on the knee' and to rest than non-athletes. Further, there is a trend towards increased medical consumption among athletes while functional disability and pain are lower than among the non-athletes.

Corticosteroids reduce the tensile strength of isolated collagen fascicles

BACKGROUND

Overuse tendon injuries are frequent. Corticosteroid injections are commonly used as treatment, although their direct effects on the material properties of the tendon are poorly understood.

PURPOSE

To examine the influence of corticosteroids on the tensile strength of isolated collagen fascicles.

STUDY DESIGN

Controlled laboratory study.

METHODS

Single strands (300-500 mum) of rat-tail collagen fascicles were incubated in either high (1 mL of 40 mgmL(-1) mixed with 0.5 mL saline 9%) or low (1 mL of 40 mgmL(-1) mixed with 2 mL saline 9%) concentration of methylprednisolone acetate (Depomedrol) for 3 or 7 days, while the control segment from the same fascicle was kept in saline (N = 64). After the incubation period, the fascicles underwent displacement to failure in a mechanical test rig at 0.13 mm/s, and thereafter hydroxylysyl pyridinoline and lysyl pyridinoline cross-link content was evaluated in a high-performance liquid chromatography system. Data for each group were analyzed with a 2-way analysis of variance (time x incubation) for ultimate stress (mean +/- standard deviation).

RESULTS

In the high-concentration groups, strength was reduced after 3 (16.6 +/- 4.6 MPa) and 7 (8.6 +/- 1.7 MPa) days compared to the controls (30.2 +/- 5.0 MPa and 25.6 +/- 4.6 MPa, respectively; P < .05). In the low-concentration groups, strength was reduced after 3 (12.0 +/- 3.1 MPa) and 7 days (10.9 +/- 2.5 MPa) compared to the controls (31.5 +/- 5.0 MPa and 32.4 +/- 5.6 MPa, respectively; P < .05). The amount of cross-linking was unaffected by the intervention.

CONCLUSION

Data show that the tensile strength of isolated fascicles is markedly reduced after 3- and 7-day incubation in both high and low concentration of corticosteroids, although the observed effect on whole tendon remains unknown.

CLINICAL RELEVANCE

Corticosteroids may weaken specific regions of the injected tendon and leave it more prone to rupture. This weakening effect is manifested in the individual collagen fascicles that constitute the tendon.

Ultrasound-guided sclerosis of neovessels in painful chronic patellar tendinopathy: a randomized controlled trial

BACKGROUND

Color Doppler ultrasound examination frequently reveals neovascularization in chronic painful Achilles and patellar tendinopathy. Sclerosing the area with vascular ingrowth using polidocanol has shown promising clinical results in patients with Achilles tendinopathy.

PURPOSE

To investigate sclerosing treatment using polidocanol on a group of elite athletes with patellar tendinopathy.

STUDY DESIGN

Randomized controlled trial/cross-over study; Level of evidence, 1.

METHODS

The authors recruited 33 patients (42 tendons), mainly from the Norwegian elite divisions in basketball, team handball, and volleyball. Seventeen patients (23 knees) were randomized to the treatment group (polidocanol injections in the area of neovascularization) and 16 patients (20 knees) to the control group (similar injections with lidocaine/epinephrine). After 4 months of treatment, the control group was crossed over to active treatment. Pain and function were recorded using the Victorian Institute of Sport Assessment score before the start of treatment and 4, 8, and 12 months after the first injection. Victorian Institute of Sport Assessment scores between groups were compared using multivariate analysis of variance for repeated measures.

RESULTS

The treatment group reported a significant improvement in Victorian Institute of Sport Assessment score from 51 to 62 after 4 months; there was no change for the control group (group by time interaction, P = .052). After 8 months, when the control group had also received active treatment with polidocanol, they had a greater improvement in Victorian Institute of Sport Assessment score (58-79) than did the treatment group (54-70; group by time interaction, P = .022; time effect, P < .0001). There was no further time or group effect in Victorian Institute of Sport Assessment score to the 12-month follow-up (treatment, 72; control, 85).

CONCLUSION

Sclerosing injections with polidocanol resulted in a significant improvement in knee function and reduced pain in patients with patellar tendinopathy.

Arthroscopic patellar release for the treatment of chronic patellar tendinopathy

We describe an arthroscopic technique for the treatment of chronic patellar tendinopathy (jumper's knee). Preoperatively, tendon necrosis or rupture is excluded by sonography. Diagnostic arthroscopy is performed and hypertrophic synovitis around the inferior patellar pole is removed with a bipolar cautery system. Two outside-in cannulas mark the clinically symptomatic region, mainly found between the tendon insertion site and the lateral aspects of the patellar tendon. The bipolar cautery is used for a release of the paratenon and a bone denervation at the inferior patellar pole including the tendon insertion site within the marked area. No tendon or bone material is removed or excised throughout the procedure. We treated 15 athletes with stage 3 and 4 chronic patellar tendinopathies on a modified version of the Blazina score (0-5). Patients' mean age was 29 years and the mean follow-up period was 41 months. In 13 cases, clinical symptoms subsided completely within 3 months after surgery. The mean preoperative Blazina score was 3.7 (SD, 0.5) and the mean postoperative Blazina score was 0.4 (SD, 1.0; paired 2-tailed t test, P < .01). Ultrasound showed a reduction of tendon edema within 3 weeks and no signs of edema within a mean period of 5 weeks after surgery. The minimal surgical impact to the tendon allows early and functional rehabilitation. The technique is effective, easy to perform, and safe to apply.

Ultrasound appearance of tendon tears. Part 2: lower extremity and myotendinous tears

Traumatic tears of the musculotendinous complex at the lower limb are common in clinical practice but can be difficult to detect and to evaluate because of swelling and pain that can limit proper physical examination. They can affect sedentary subjects or active sports participants involved in amateur or professional activities. In the first group tendons are more commonly affected, while myotendinous tears are common in sports players. The aims of this review article are to review the aetiology and pathomechanism of the most common ruptures affecting the tendons and the main myotendinous junctions of the lower extremity and to describe their ultrasound findings as well as to correlate ultrasound appearance with that of the other imaging modalities.

No effect of eccentric training on jumper's knee in volleyball players during the competitive season: a randomized clinical trial

BACKGROUND

The effect of surgery on patellar tendinopathy (jumper's knee) is questionable, and conservative treatment protocols have not been properly documented.

PURPOSE

: The aim of this study was to investigate the effect of a newly developed eccentric training program for patellar tendinopathy in volleyball players during the competitive season.

STUDY DESIGN

Randomized clinical trial.

METHODS

Patients were recruited from male and female elite volleyball teams in Norway, and the diagnosis was based on clinical examination alone. Of 51 players diagnosed with patellar tendinopathy, 29 could be included in the study. The training group (n = 13) performed squats on a 25 degrees decline board as a home exercise program (3 x 15 repetitions twice daily) for a 12-week intervention period during the final half of the competitive season. The eccentric (downward) component was done on the affected leg. The control group (n = 16) trained as usual. The primary outcome was a symptom-based questionnaire developed specifically for patellar tendinopathy (Victorian Institute of Sport Assessment score), and patients were followed up before and after the intervention period, as well as after 6 and 30 weeks. All subjects self-recorded training to document their activity level (eccentric training, volleyball training, matches, other training).

RESULTS

There was no change in Victorian Institute of Sport Assessment score during the intervention period in the training (pre, 71.1 +/- 11.3; post, 70.2 +/- 15.4) or control group (pre, 76.4 +/- 12.1; post, 75.4 +/- 16.7), nor was there any change during the follow-up period at 6 weeks or 6 months. The training group completed 8.2 +/- 4.6 weekly sessions of eccentric training during the intervention period (59% of the recommended volume), and there was no difference between groups in training or competition load.

CONCLUSION

There was no effect on knee function from a 12-week program with eccentric training among a group of volleyball players with patellar tendinopathy who continued to train and compete during the treatment period. Whether the training would be effective if the patients did not participate in sports activity is not known.

Patellar tendinopathy in athletes: current diagnostic and therapeutic recommendations

Formerly known as 'jumper's knee', patellar tendinopathy gives rise to considerable functional deficit and disability in recreational as well as professional athletes. It can interfere with their performance, often perseveres throughout the sporting career and may be the primary cause to end it. The diagnosis of patellar tendinopathy is primarily a clinical one but new imaging techniques, such as Doppler ultrasonography, may provide additional diagnostic value. Current therapeutic protocols are characterised by wide variability ensuing from anecdotal experience rather than evidence. Moreover, numerous reports in recent years have shattered previous doctrines and dogmatic belief on tendon overuse. Histopathological and biochemical evidence has indicated that the underlying pathology of tendinopathy is not an inflammatory tendinitis but a degenerative tendinosis. Consequently, pain in chronic patellar tendinopathy is not inflammatory in nature, but its exact origin remains unexplained. In pursuit of pathology- and evidence-based management, conservative therapy should be shifted from anti-inflammatory strategies towards a complete rehabilitation with eccentric tendon strengthening as a key element. If conservative management fails, surgery is opted for. However, considering the heterogeneity of surgical procedures and the absence of randomised studies, no conclusive evidence can be drawn from the literature regarding the effectiveness of surgical treatment for patellar tendinopathy. Parallel with the improved knowledge on the pathophysiology and pain mechanisms in patellar tendinopathy, new treatment strategies are expected to emerge in the near future.