Operative treatment of partial rupture of the patellar ligament. A study of 138 cases

Partial Patellar Tendon Tears in Athletes: A Systematic Review of Treatment Options, Outcomes, and Return to Sport

Introduction

Partial patellar tendon tears (PPTTs) are overuse injuries in sports with frequent jumping, such as basketball and volleyball. There are several treatment options, including both operative and non-operative modalities. Current literature is largely focused broadly on patellar tendinopathy; however, there are few studies which specifically evaluate treatment outcomes for PPTTs.

Objective

To systematically review the literature on treatment options, clinical outcomes, and return to sport (RTS) in athletes with a PPTT.

Methods

PubMed, Embase, and Cochrane were searched through May 1st, 2023 for studies reporting treatment outcomes in athletes with partial patellar tendon tears. Data was extracted on the following topics: treatment modalities, surgical failures/reoperations, surgical complications, RTS, and postoperative time to RTS.

Results

The review covers 11 studies with 454 athletes: 343 males (86.2%) and 55 females (13.8%). The average age was 25.8 years, ranging from 15 to 55 years. 169 patients (37.2%) received only non-operative treatments, while 295 (65.0%) underwent surgery. 267 patients (92.1%) returned to sports after 3.9 months of treatment. The average follow-up was 55.8 months.

Conclusion

Our review of current literature on PPTTs in athletes illustrates over 90% return to sport following either conservative or surgical treatment. There is currently little data that directly compares the treatment options to establish an evidence-based "gold-standard" treatment plan. The data we present suggests that current treatment options are satisfactory but would benefit from future study.

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.

Surgical Management of Patellar Tendinopathy Results in Improved Outcomes and High Rates of Return to Sport: A Systematic Review

Although the majority of patients with patellar tendinopathy (PT) can be treated nonoperatively, operative management may be indicated for recalcitrant cases. While several surgical techniques have been described, there is limited understanding of postoperative outcomes and expectations regarding return to activity and sport. The purpose of this study was to characterize the clinical outcomes associated with the surgical management of PT with an emphasis on return to sport (RTS) rates. We hypothesized that surgical management would lead to clinically important improvements in patient-reported outcomes (PROs) with high rates of RTS and RTS at the same level. A comprehensive search of the PubMed, Medline, and Embase databases was performed in December 2020. Level of evidence studies I through IV, investigating results of surgical management for PT (PRO, functional outcomes, pain, and/or RTS), were included. The search was performed in accordance with the Preferred Reported Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Forty clinical studies reporting on surgery for PT satisfied inclusion criteria, with 1,238 total knees undergoing surgery for PT. A comparison of pre- and postoperative Victorian Institute of Sport Assessment, patellar tendon (VISA-P) scores (mean difference: 41.89, p < 0.00001), Lysholm scores (mean difference: 41.52, p < 0.00001), and visual analogue scale (VAS) pain scores (mean difference: 5, p < 0.00001) demonstrated clinically and statistically significant improvements after surgery. The overall RTS rate following operative management was 89.8% (95% confidence interval [CI]: 86.4-92.8, I ² = 56.5%) with 76.1% (95% CI: 69.7.5-81.9, I ² = 76.4%) of athletes returning to the same level of activity. Surgery for PT provides meaningful improvement in patient reported outcomes and pain while allowing athletes to RTS at high rates with levels of participation similar to that of preinjury. Comparative studies of open and/or arthroscopic surgery are still limited but current evidence suggests better rates of RTS for arthroscopic surgery compared with open surgery. This is a systematic review of level-I to -IV studies.

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.

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 past, present and future in scaffold-based tendon treatments

Tendon injuries represent a significant clinical burden on healthcare systems worldwide. As the human population ages and the life expectancy increases, tendon injuries will become more prevalent, especially among young individuals with long life ahead of them. Advancements in engineering, chemistry and biology have made available an array of three-dimensional scaffold-based intervention strategies, natural or synthetic in origin. Further, functionalisation strategies, based on biophysical, biochemical and biological cues, offer control over cellular functions; localisation and sustained release of therapeutics/biologics; and the ability to positively interact with the host to promote repair and regeneration. Herein, we critically discuss current therapies and emerging technologies that aim to transform tendon treatments in the years to come.

Open versus arthroscopic surgical treatment of chronic proximal patellar tendinopathy. A systematic review

PURPOSE

A general agreement on the best surgical treatment option of chronic proximal patellar tendinopathy is still lacking. The purpose of this systematic review was to investigate if arthroscopically assisted procedures have been reported better results compared to open surgery and to assess the methodology of studies.

METHODS

Twenty-one studies were included in the review. Surgical outcomes were defined referring to the functional classification described by Kelly et al. (Am J Sports Med 12(5):375-380, [11]): return to sport was regarded as the ability of training at the original level before injury with mild or moderate pain and success as the improvement after surgery with symptom reduction. Methodological analysis was performed by two reviewers adopting the Coleman Methodology Score (CMS) (range 0-100, best score 100).

RESULTS

Only one randomized controlled trial (RCT) met inclusion criteria; all other included studies were case series. Median sample size 24, range 11-138, mean age at surgery 26.8 ± 3.2 years, mean follow-up 32.5 ± 18.4 (median 31, range 6-60) months. Return to sport rate: global 78.5 %, open group 76.6 % and arthroscopic group 84.2 %. Success rate: global 84.6 %, open group 87.2 % and arthroscopic group 92.4 %. Differences between groups were not statistically significant. CMSs were positively correlated with the year of publication (P < 0.05).

CONCLUSIONS

Minimally invasive arthroscopically assisted procedures have not reported better statistically significant results when compared to open surgery in the treatment of chronic proximal patellar tendinopathy. The methodology of studies in this field has improved over the past 15 years, but well-designed RCTs using validated patient-based outcome measures are still lacking.

LEVEL OF EVIDENCE

Systematic Review, Level IV.

Inflammation in overuse tendon injuries

Overuse tendon injuries present with pain and swelling of the affected tendon with associated decrease in exercise tolerance and function of the limb. After early inflammatory and degenerative hypotheses, the term "tendinopathy" is now deemed a more appropriate reflection of the mixed histopathological picture seen in operative biopsies from affected patients. The condition presents histopathological evidence of "failed healing response," but its etiology remains unclear. The incidence of tendinopathy is increased in individuals with obesity and decreased insulin sensitivity (as seen in type 1 and type 2 diabetes mellitus). These groups of patients also exhibit an increased risk of developing a state of chronic low-grade, systemic inflammation. This paper considers the theoretical bases to discuss whether these conditions may predispose to the development of tendinopathy and the implication that such a relationship may have on its management.

Tendinopathy and Inflammation: Some Truths

Overuse tendinopathies are a common cause of pain and disability in athletes. According to histological findings, it is a “failed healing response” to overuse tendon injury. In obesity, macrophages and mast cells migrate to adipose tissue, and the resulting decreased availability of immune circulating cells should be responsible for less effective immune responses to acute tendon injury. In diabetic patients, free glucose molecules attach to collagen, alter collagen solubility, increase resistance to enzymatic degradation, and impair cross linking, contributing to the subsequent development of chronic tendinopathy secondary to a failed healing response to a tendon insult. Prolonged systemic, low-grade inflammation and impaired insulin sensitivity act as a risk factor for a “failed healing response” after an acute tendon insult, and predispose to the development of chronic overuse tendinopathies. Further studies may reveal novel therapeutic treatment approaches.

Surgical treatment of patellar tendinopathy in athletes. A retrospective multicentric study

The purpose of this study was to evaluate the results of surgery, in particular arthroscopic procedures in the treatment of patellar tendinopathies that are refractory to conservative treatment in athletes.

METHOD

A retrospective multicenter study was performed in four centers. Patients were athletes who did not respond to carefully followed conservative treatment and who underwent surgery. Sixty-four patients were included, 10 who underwent arthroscopy. Patients were questioned and followed-up for an average of 22 months (6-116 months).

RESULTS

At the final follow-up, 87% of the patients had an improved Blazina score and 63% were again practicing their sport at the same level. None of the preoperative factors influenced the final result and one surgical technique was not more effective than another (patellar tip resection versus arthroscopic approach).

DISCUSSION

The results of this study are comparable to those in the literature which show a success rate of more than 80% whatever the surgical technique. This study limits a certain number of biases because the patient group is homogenous (athletes, unsuccessful conservative treatment) with similar functional scores, and well-defined protocols for postoperative rehabilitation. However, the study of this entity is difficult because of the limited number of subjects and its different anatomopathological forms.

CONCLUSION

Surgical treatment is indicated in motivated athletes if carefully followed conservative treatment is unsuccessful after more than six months, making it impossible to practice a sport (Blazina grade 3). Arthroscopic techniques seem to be as effective as open surgery with an equivalent delay for beginning sports activities.

Management of tendinopathy

Overuse disorders of tendons, or tendinopathies, present a challenge to sports physicians, surgeons, and other health care professionals dealing with athletes. The Achilles, patellar, and supraspinatus tendons are particularly vulnerable to injury and often difficult to manage successfully. Inflammation was believed central to the pathologic process, but histopathologic evidence has confirmed the failed healing response nature of these conditions. Excessive or inappropriate loading of the musculotendinous unit is believed to be central to the disease process, although the exact mechanism by which this occurs remains uncertain. Additionally, the location of the lesion (for example, the midtendon or osteotendinous junction) has become increasingly recognized as influencing both the pathologic process and subsequent management. The mechanical, vascular, neural, and other theories that seek to explain the pathologic process are explored in this article. Recent developments in the nonoperative management of chronic tendon disorders are reviewed, as is the rationale for surgical intervention. Recent surgical advances, including minimally invasive tendon surgery, are reviewed. Potential future management strategies, such as stem cell therapy, growth factor treatment, and gene transfer, are also discussed.

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.

Chronic tendinopathy tissue pathology, pain mechanisms, and etiology with a special focus on inflammation

Continuing progress in research in molecular biology and biomechanics has provided considerable new information and has given rise to new hypotheses in chronic tendinopathy. Overloading is still, however, crucial in the development of tendinopathy. Most of the histologic findings in tendinopathy represent chronic degeneration, regeneration, and microtears of the tendinous tissue. The prevailing opinion is that no histological evidence of acute inflammation has been documented, but in newer studies using immunohistochemistry and flow cytometry inflammatory cells have been detected. The existing data indicate that the initiators of the tendinopathic pathway include many proinflammatory agents (e.g. cytokines, prostaglandins, different growth factors, and neuropetides). Because of the complex interaction between the classic proinflammatory agents and the neuropeptides, it seems impossible and somewhat irrelevant to distinguish sharply between chemical and neurogenic inflammation. Furthermore, glucocorticoids are, at the moment, the most effective treatment in tendinopathy with regard to reduction of pain, tendon thickness, and neovascularization. This review indicates - despite a great deal of uncertainty regarding the concepts - that an inflammatory process may be related not only to the development of tendinopathy but also chronic tendinopathy. More attention should be directed towards the "tendinitis myth" in the future.

Treatment of Jumper's knee: promising short-term results in a pilot study using a new arthroscopic approach based on imaging findings

Sclerosing injections targeting the area with neovessels and nerves on the dorsal side of the patellar tendon has been demonstrated as giving promising clinical results in patients with chronic painful Jumper's knee-patellar tendinosis (PT). However, a mean number of three treatments with 6-8 weeks in between were needed for a good clinical result. This study aimed to evaluate a more radical removal of the area with neovessels and nerves by using arthroscopic shaving. Fifteen patients (12 men and three women) with the diagnose Jumper's knee-PT in altogether 15 patellar tendons were included. All patients had a long duration of pain-symptoms (mean 27 months) from the patellar tendon, and ultrasonography (US) + colour Doppler (CD) examination showed structural tendon changes with hypo-echoic areas and a neovascularisation inside and on the dorsal side of the tendon, corresponding to the painful area. All patients were treated with arthroscopic shaving of the dorsal side of the proximal tendon. At follow-up (mean 6 months) after treatment, there was a good clinical result in 13/15 tendons (6/8 elite athletes). The satisfied patients were back to previous (before injury) sport activity level, and the amount of pain recorded on a visual analogue scale (VAS)-scale had decreased significantly (VAS from 79 to 12, P < 0.05). A telephone follow-up 13 months (mean) postoperatively showed that the same 13/15 were still satisfied and active in their sports, and that the 2/15 poor cases were still not satisfied with the treatment. Our short-term results indicate that arthroscopic shaving targeting the area with neovessels and nerves on the dorsal side of the patellar tendon has a potential to reduce the tendon pain and allow for the majority of patients to go back to full tendon loading activity within 2 months after surgery. Further studies evaluating this new technique for treating Jumper's knee-PT are in progress.

Is the chronic painful tendinosis tendon a strong tendon?: a case study involving an Olympic weightlifter with chronic painful Jumper's knee

The chronic painful tendinosis tendon is generally considered a degenerated and weak tendon. However, this has not been scientifically verified, and is to be considered a hypothesis. We present here a case study involving a high-level Olympic weightlifter with chronic painful patellar tendinosis who started heavy-weight training very early after successful treatment with sclerosing injections. A 25-year-old super heavy-weight (+105 kg) Olympic weightlifter with 9 months duration of severe pain (prohibiting full training) in the proximal patellar tendon, where ultrasound and Doppler showed a widened tendon with structural changes and neovascularisation, was given one treatment with ultrasound and Doppler-guided injections of the sclerosing agent polidocanol. The injections targeted the neovessels posterior to the tendon. The patient was pain-free after the treatment, and already after 2-weeks he started with heavy-weight training (240 kg in deep squats) to try to qualify for the Olympics. Additional very heavy training on training camps, most often without having any discomfort or pain in the patellar tendon, resulted in Swedish records and ninth place at the European Championships 17 weeks after the treatment. Despite beating the national records, he did not qualify for the Olympics. Ultrasound and Doppler follow-ups have shown only a few remaining neovessels, and little structural tendon changes. This case questions previous theories about the weak tendinosis tendon, and stresses the importance of studies evaluating tendon strength.

Surgical treatment compared with eccentric training for patellar tendinopathy (Jumper's Knee). A randomized, controlled trial

BACKGROUND

Although the surgical treatment of patellar tendinopathy (jumper's knee) is a common procedure, there have been no randomized, controlled trials comparing this treatment with forms of nonoperative treatment. The purpose of the present study was to compare the outcome of open patellar tenotomy with that of eccentric strength training in patients with patellar tendinopathy.

METHODS

Thirty-five patients (forty knees) who had been referred for the treatment of grade-IIIB patellar tendinopathy were randomized to surgical treatment (twenty knees) or eccentric strength training (twenty knees). The eccentric training group performed squats on a 25 degrees decline board as a home exercise program (with three sets of fifteen repetitions being performed twice daily) for a twelve-week intervention period. In the surgical treatment group, the abnormal tissue was removed by means of a wedge-shaped full-thickness excision, followed by a structured rehabilitation program with gradual progression to eccentric training. The primary outcome measure was the VISA (Victorian Institute of Sport Assessment) score (possible range, 0 to 100), which was calculated on the basis of answers to a symptom-based questionnaire that was developed specifically for patellar tendinopathy. The patients were evaluated after three, six, and twelve months of follow-up.

RESULTS

There was no difference between the groups with regard to the VISA score during the twelve-month follow-up period, but both groups had improvement (p < 0.001). The mean combined VISA score for the two groups increased from 30 (95% confidence interval, 25 to 35) before the start of treatment to 49 (95% confidence interval, 42 to 55) at three months, 58 (95% confidence interval, 51 to 65) at six months, and 70 (95% confidence interval, 62 to 78) at twelve months. In the surgical treatment group, five knees had no symptoms, twelve had improvement but were still symptomatic, two were unchanged, and one was worse after twelve months (p = 0.49 compared with the eccentric training group). In the eccentric training group, five knees did not respond to treatment and underwent secondary surgery after three to six months. Of the remaining fifteen knees in the eccentric training group, seven had no symptoms and eight had improvement but were still symptomatic after twelve months.

CONCLUSIONS

No advantage was demonstrated for surgical treatment compared with eccentric strength training. Eccentric training should be tried for twelve weeks before open tenotomy is considered for the treatment of patellar tendinopathy.

Current concepts in the management of tendon disorders

Primary disorders of tendons are common and constitute a high proportion of referrals to rheumatologists. Certain tendons are particularly vulnerable to degenerative pathology; these include the Achilles, patella, elements of the rotator cuff, forearm extensors, biceps brachi and tibialis posterior tendons. Disorders of these tendons are often chronic and can be difficult to manage successfully in the long term. Significant advances have been made in understanding the pathophysiology of these conditions. Histopathological evidence, together with advances in imaging techniques, has made us more appreciative of the degenerative (rather that inflammatory) nature of these conditions. Additionally the presence of neovascularization is now well-recognized in long-standing tendinopathy. We review the mechanical, vascular and developing neural theories that attempt to explain the aetiology of degenerative tendinopathy. We also explore theories of why specific tendons (such as the Achilles and supraspinatus tendons) are particularly prone to degenerative pathology. Traditionally, treatments have placed a heavy emphasis on anti-inflammatory strategies, which are often inappropriate. Recently, however, significant advances in the practical management of tendon disorders have been made. In particular the advent of 'eccentric loading' training programmes has revolutionized the treatment of Achilles tendinopathy in some patients. This concept is currently being extended to include other commonly injured tendons. Other current treatments are reviewed, as are potential future treatments.

Biomechanical basis for tendinopathy

Tendinopathy affects millions of people in athletic and occupational settings and is a nemesis for patients and physicians. Mechanical loading is a major causative factor for tendinopathy; however, the exact mechanical loading conditions (magnitude, frequency, duration, loading history, or some combinations) that cause tendinopathy are poorly defined. Exercise animal model studies indicate that repetitive mechanical loading induces inflammatory and degenerative changes in tendons, but the cellular and molecular mechanisms responsible for such changes are not known. Injection animal model studies show that collagenase and inflammatory agents (inflammatory cytokines and prostaglandin E1 and E2) may be involved in tendon inflammation and degeneration; however, whether these molecules are involved in the development of tendinopathy because of mechanical loading remains to be verified. Finally, despite improved treatment modalities, the clinical outcome of treatment of tendinopathy is unpredictable, as it is not clear whether a specific modality treats the symptoms or the causes. Research is required to better understand the mechanisms of tendinopathy at the tissue, cellular, and molecular levels and to develop new scientifically based modalities to treat tendinopathy more effectively.

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.

Prevalence of jumper's knee among elite athletes from different sports: a cross-sectional study

BACKGROUND

The prevalence of jumper's knee across different sports has not been examined, and it is not known if there is a gender difference. Data from surgical case series indicate that there may be a high prevalence in sports with high speed and power demands.

HYPOTHESIS

The aim of this study was to estimate the prevalence of jumper's knee in different sports among female and male athletes and to correlate the prevalence to the loading characteristics of the extensor mechanism in these sports.

STUDY DESIGN

Cross-sectional study; Level of evidence, 4.

METHODS

The authors examined approximately 50 Norwegian male and female athletes at the national elite level from each of the following 9 sports: athletics (male athletes: high jump, 100- and 200-m sprint), basketball (male athletes), ice hockey (male athletes), volleyball (male athletes), orienteering (male athletes), road cycling (male athletes), soccer (male and female athletes), team handball (male and female athletes), and wrestling (male athletes). The examination included an interview on individual characteristics (weight, age, height, and training background), a clinical examination, and self-recorded Victorian Institute of Sport Assessment score from 0 (worst) to 100 (best).

RESULTS

The overall prevalence of current jumper's knee was 14.2% (87 of 613 athletes), with a significant difference between sports with different performance characteristics (range, 0%-45%). In addition, 51 athletes (8%) reported previous symptoms. The prevalence of current symptoms was highest in volleyball (44.6%+/-6.6%) and basketball (31.9%+/-6.8%), whereas there were no cases in cycling or orienteering. The prevalence of current jumper's knee was lower among women (5.6%+/-2.2%) compared with men (13.5%+/-3.0%; chi2 test, P=.042). The duration of symptoms among athletes with current jumper's knee (n=87) was 32+/-25 (standard deviation) months, with a Victorian Institute of Sport Assessment score of 64+/-19.

CONCLUSION

The prevalence of jumper's knee is high in sports characterized by high demands on speed and power for the leg extensors. The symptoms are often serious, resulting in long-standing impairment of athletic performance.

Neovascularisation in chronic painful patellar tendinosis--promising results after sclerosing neovessels outside the tendon challenge the need for surgery

Sclerosing injections targeting neovascularisation have been demonstrated to give promising clinical results in patients with chronic painful Achilles tendinosis. In this study, fifteen elite or recreational athletes (12 men and three women) with the diagnosis patellar tendinosis/Jumper's knee in 15 patellar tendons were included. All the patients had a long duration of pain symptoms (mean = 23 months) from the patellar tendon, and ultra-sonography + colour doppler examination showed structural tendon changes with hypo-echoic areas and a neovascularisation, corresponding to the painful area. The patients were treated with ultrasound and colour doppler-guided injections of the sclerosing substance Polidocanol, targeting the area with neovascularisation. At follow-up (mean = 6 months) after a mean amount of three treatments, there was a good clinical result in 12/15 tendons. The patients were back to their previous (before injury) sport activity level, and the amount of pain recorded on a VAS-scale had decreased significantly (VAS from 81 to 10). Our findings indicate that treatment with sclerosing injections, targeting the area with neovessels in patellar tendinosis, has the potential to cure the pain in the tendons and also allow the patients to go back to full patellar-tendon loading activity.

Tendon injury and tendinopathy: healing and repair

Tendon disorders are frequent and are responsible for substantial morbidity both in sports and in the workplace. Tendinopathy, as opposed to tendinitis or tendinosis, is the best generic descriptive term for the clinical conditions in and around tendons arising from overuse. Tendinopathy is a difficult problem requiring lengthy management, and patients often respond poorly to treatment. Preexisting degeneration has been implicated as a risk factor for acute tendon rupture. Several physical modalities have been developed to treat tendinopathy. There is limited and mixed high-level evidence to support the, albeit common, clinical use of these modalities. Further research and scientific evaluation are required before biological solutions become realistic options.

Similar histopathological picture in males with Achilles and patellar tendinopathy

PURPOSE

To ascertain whether there are differences in the histopathological appearance of tendinopathic Achilles and patellar tendons.

METHODS

In males, we studied biopsies from tendinopathic Achilles (N = 28; average age 34.1 yr) and patellar tendons (N = 28; average age 32.1), Achilles tendons (N = 21; average age 61.8 yr) from deceased patients with no known tendon pathology, and patellar tendons (N = 15; average age 28.3) from patients undergoing anterior cruciate ligament reconstruction. Hematoxylineosin stained slides were interpreted using a semiquantitative grading scale (0: normal to 3: maximally abnormal) for fiber structure, fiber arrangement, rounding of the nuclei, regional variations in cellularity, increased vascularity, decreased collagen stainability, and hyalinization. All slides were assessed blindly twice, the agreement between two readings ranging from 0.170 to 0.750 (kappa statistics).

RESULTS

The highest mean score of tendinopathic Achilles tendons was not significantly different from that of tendinopathic patellar tendons (11.6 +/- 5 and 10.4 +/- 3, respectively). The ability to differentiate between an Achilles tendon and a patellar tendon was low.

CONCLUSIONS

Tendinopathic Achilles and patellar tendons show a similar histological picture. It was not possible to identify whether a specimen had been harvested from an Achilles or a patellar tendon on the basis of histological examination. The general pattern of degeneration was common to both tendinopathic Achilles and patellar tendons. A common, as yet unidentified, etiopathological mechanism may have acted on both these tendon populations.

Thermal microdebridement does not affect the time zero biomechanical properties of human patellar tendons

BACKGROUND

Thermal microdebridement for the treatment of chronic tendinopathy has recently been introduced. The effect of thermal microdebridement on the biomechanical properties of human tendons, however, remains unknown.

HYPOTHESIS

Thermal microdebridement does not affect the biomechanical properties of human patellar tendons in a cadaveric model at the time of initial treatment.

STUDY DESIGN

Controlled laboratory study.

METHODS

The central 15 mm of 12 matched, human (mean age, 71 years; 8 male, 4 female), fresh-frozen patellar tendons was divided into 3 equal 5-mm specimens. The treatment group (n = 12) underwent thermal microdebridement with a radiofrequency probe. A sham treatment group (n = 12) underwent insertion of a deactivated probe. The control group (n = 12) underwent no treatment. After treatment, each specimen was tested to failure in a servo-hydraulic materials testing machine at an elongation rate of 3 mm/s. One-way repeated measures analysis of variance was used to determine differences between groups.

RESULTS

No significant difference in ultimate stress at failure, elastic modulus, strain energy density, or strain at maximum load was found between the groups. The ultimate stress at failure for the treatment, sham, and control groups was 61.0, 66.7, and 63.0 MPa, respectively (P = .653), and the strain at maximum load was 0.12, 0.11, and 0.09, respectively (P = .279).

CONCLUSIONS

Thermal microdebridement does not affect the biomechanical properties of cadaveric human patellar tendons at the time of initial treatment.

CLINICAL RELEVANCE

It may be safe to proceed with aggressive rehabilitation after thermal microdebridement of the patellar tendon. However, the results in this cadaveric model should be interpreted with caution. Additional studies using an in vivo model will be required to completely assess the effects of thermal microdebridement on the biomechanical properties of human patellar tendons.

Comparison of effects of exercise programme, pulsed ultrasound and transverse friction in the treatment of chronic patellar tendinopathy

OBJECTIVE

To compare the effectiveness of an exercise programme, pulsed ultrasound and transverse friction in the treatment of chronic patellar tendinopathy.

DESIGN

Randomized controlled trial.

SETTING

Rheumatology and Rehabilitation Centre.

SUBJECTS

This study was carried out with 30 patients who had chronic patellar tendinopathy. They were randomized into three groups.

INTERVENTIONS

Group A (n = 10) was treated with exercise programme. Pulsed ultrasound was given to group B (n = 10). Group C (n = 10) received transverse friction. All patients received three treatments per week for four weeks.

OUTCOMES

Patients' pain was evaluated at the end of the four-week course of treatment (week 4), one month (week 8) and three months (week 16) after the end of treatment.

RESULTS

The exercise programme was statistically significantly better than the other two treatments at the end of treatment (chi2 = 12.21, p < 0.01), one month (chi2 = 23.2, p < 0.001) and three months (chi2 = 23.2, p < 0.001) after the end of the treatment.

CONCLUSION

Although the results suggested that the exercise programme was more effective treatment than ultrasound and transverse friction at the end of the treatment as well as at the follow-ups, future controlled studies are needed to establish the relative and absolute effectiveness of each of the three treatment interventions.

The painful nonruptured tendon: clinical aspects

Tendon conditions cause a great deal of morbidity in both elite and recreational athletes, and outcome of treatment is often unsatisfactory. Evidence that the common clinical conditions (e.g., Achilles, patellar, elbow and rotator cuff tendinopathies) are due to tendinosis has been present for many years, yet the misnomer "tendinitis" is still widely used for these conditions in clinical practice. Clinical practice remains very different from evidence-based recommendations [8], but this is a common challenge in medical practice. Thus, in addition to further research in an area of medicine rife for such endeavor, there must be attention to knowledge translation--ensuring that the patient benefits from what is already known.

Performance characteristics of volleyball players with patellar tendinopathy

BACKGROUND

Patellar tendinopathy is assumed to result from chronic tendon overload. There may be a relationship between tendon pain and jumping ability.

HYPOTHESIS

There is no difference in performance characteristics between volleyball players with patellar tendinopathy and those without.

STUDY DESIGN

Prospective cohort study.

METHOD

We examined the performance of the leg extensor apparatus in high-level male volleyball players with patellar tendinopathy (N = 24) compared with a control group (N = 23) without knee symptoms. The testing program consisted of different jump tests with and without added load, and a composite jump score was calculated to reflect overall performance.

RESULTS

The groups were similar in age, height, and playing experience, but the patellar tendinopathy group did more specific strength training and had greater body weight. They scored significantly higher than the control group on the composite jump score (50.3 versus 39.2), and significant differences were also observed for work done in the drop-jump and average force and power in the standing jumps with half- and full-body weight loads.

CONCLUSIONS

Greater body weight, more weight training, and better jumping performance may increase susceptibility to patellar tendinopathy in volleyball players.

Long-term prognosis for jumper's knee in male athletes. A prospective follow-up study

BACKGROUND

Little information is available on the long-term outcome of jumper's knee, a common problem among athletes.

PURPOSE

Our aim was to determine the 15-year prognosis of jumper's knee.

STUDY DESIGN

Prospective case control.

METHODS

The prognosis for jumper's knee was studied using two groups: athletes with jumper's knee and nonsymptomatic control athletes. At baseline, all subjects participated in standardized clinical examinations and measurements, and 15 years later they were asked to respond to a questionnaire.

RESULTS

Twenty athletes with jumper's knee and 16 athlete control subjects responded (response rate 74% and 84%, respectively). The jumper's knee group reported significantly more knee symptoms according to their Kujala score and more knee pain after repeated squatting. Fifty-three percent of the subjects in the jumper's knee group (9 of 17) reported that they had quit their sports career because of their knee problem, compared with 7% of the control athletes (1 of 14). Patellar height was associated with knee symptoms at follow-up.

CONCLUSION

Jumper's knee causes mild but long-lasting symptoms after an athletic career.

Management of Achilles tendinopathy by ultrasound-guided percutaneous tenotomy

PURPOSE

To report the middle to long-term results of ultrasound-guided percutaneous longitudinal tenotomy of the Achilles tendon

METHOD

Seventy-five athletes with unilateral Achilles tendinopathy underwent ultrasound-guided percutaneous longitudinal tenotomy under local anesthetic infiltration after failure of conservative management. Sixty-three patients were reviewed at least 36 months after the operation (51 +/- 18.2 months).

RESULTS

Thirty-five patients were rated excellent, 12 good, 9 fair, and 7 poor. Nine of the 16 patients with a fair or poor result underwent a formal exploration of the Achilles tendon 7-12 months after the index procedure. The operated tendons remained thickened and the ultrasonographic appearance of operated tendons remained abnormal even 8 yr after the operation, without interfering with physical training. Isometric maximal muscle strength and isometric endurance gradually returned to values similar to their contralateral unoperated tendon.

CONCLUSIONS

Percutaneous longitudinal ultrasound-guided internal tenotomy is simple, can be performed on an outpatient basis, requires minimal follow-up care, does not hinder further surgery should it be unsuccessful, and, in our experience, has produced no significant complications. It should be considered in the management of chronic Achilles tendinopathy after failure of conservative management. However, patients should be advised that, if they suffer from diffuse or multinodular tendinopathy or from pantendinopathy, a formal surgical exploration with stripping of the paratenon and multiple longitudinal tenotomies may be preferable.

Intrinsic risk factors for the development of patellar tendinitis in an athletic population. A two-year prospective study

Retrospective studies have suggested various factors that might cause a disposition to develop patellar tendinitis, but no prospective data exist to determine any relationships. The purpose of this study was to determine the intrinsic risk factors for the development of patellar tendinitis in an athletic population. Before the study, 138 male and female students of physical education were evaluated for anthropometric variables, leg alignment characteristics, and muscle tightness and strength parameters. During the 2-year study, 19 of the 138 students developed patellar tendinitis. In all cases the diagnosis was confirmed by the presence of a hypoechogenic nodular lesion in the proximal region of the patellar tendon. Univariate and stepwise discriminant function analyses were performed comparing the various measurements. These analyses revealed that the only significant determining factor was muscular flexibility, with the patellar tendinitis patients being less flexible in the quadriceps and hamstring muscles (P < 0.05). The results of this study demonstrate that lower flexibility of the quadriceps and hamstring muscles may contribute to the development of patellar tendinitis in an athletic population. Therefore, the prevention of this condition in athletes should be focused on screening for and treating poor quadriceps and hamstring muscle flexibility.

Open and arthroscopic patellar tenotomy for chronic patellar tendinopathy. A retrospective outcome study. Victorian Institute of Sport Tendon Study Group

Chronic patellar tendinopathy often requires surgical treatment. We compared the outcomes in 25 subjects (29 tendons) who had had open patellar tenotomy and 23 subjects (25 tendons) who had had arthroscopic patellar tenotomy at a mean follow-up of 3.8 and 4.3 years, respectively. At follow-up, outcomes in the open and arthroscopic groups were as follows: 1) symptomatic benefit was seen in 81% of open and 96% of arthroscopic tenotomy patients, 2) sporting success was seen in 54% of open and 46% of arthroscopic tenotomy patients, 3) median time to return to preinjury level of activity was 10 months for open and 6 months for arthroscopic tenotomy patients, and 4) median Victorian Institute of Sport Assessment score at follow-up was 88 for open and 77 for arthroscopic tenotomy patients. There were no significant differences between groups for all outcomes. The appearance of the tendon on sonography remained abnormal in over 70% of subjects at follow-up, and sonographic appearance did not correlate with clinical outcome. Thus, arthroscopic patellar tenotomy was as successful as the traditional open procedure. Both procedures provided virtually all subjects with symptomatic benefit, but only about half the subjects who underwent either open or arthroscopic patellar tenotomy were competing at their former sporting level at follow-up.

Ultrasound-guided percutaneous longitudinal tenotomy for the management of patellar tendinopathy

Thirty-eight athletes with unilateral patellar tendinopathy (17 with a tendinopathy of the main body of the tendon, and 21 with an insertional tendinopathy) underwent ultrasound-guided multiple percutaneous longitudinal tenotomy under local anaesthetic infiltration after failure of conservative management. Thirty-four patients were reviewed at least 24 months after the operation. Sixteen patients were rated excellent, nine good, eight fair, and five poor. Nine of the 13 patients with a fair or poor result had an insertional tendinopathy, and eight of them underwent a formal exploration of the patellar tendon. Before the operation, there were some areas of altered echogenicity at and around the site of involvement. These were still visible 6 wk after surgery in 70% of the patients. At the latest follow-up, in the patients with an excellent or good result, the tendon was generally isoechogenic but slightly thicker (P = 0.06) than the normal contralateral. In the patients with a fair or poor result, the tendon was significantly thicker than the contralateral (P = 0.03), and showed some areas of mixed echogenicity. In the patients in whom the procedure was successful, the thicker operated tendon did not interfere with physical training. Bilateral isokinetic peak torque (Nm), average work (Joules), and average power (Watts) were tested at 90 degrees x s(-1). Immediately before the operation, there was no significant difference in peak torque, but total work and average power were significantly lower in the limb to be operated (0.01 < P < 0.05). By the end of the study, although peak torque was, on average, within 7% of the unoperated limb, total work and average power were still significantly lower than in the unoperated limb (0.01 < P < 0.04). Percutaneous longitudinal internal tenotomy is simple, can be performed on an outpatient basis, requires minimal follow-up care, does not hinder further surgery should it be unsuccessful, and, in our experience, has produced no significant complications. In our hands, it has become the first line operative intervention in the treatment of chronic patellar tendinopathy after failure of conservative management. However, patients should be advised that, if they suffer from an tendinopathy at the attachment of the patellar tendon at the lower pole of the patella, a formal surgical exploration with stripping of the paratenon is preferable.

A cross sectional study of 100 athletes with jumper's knee managed conservatively and surgically. The Victorian Institute of Sport Tendon Study Group

OBJECTIVES

Jumper's knee causes significant morbidity in athletes of all standards. However, there are few reference data on the clinical course of this condition in a large number of patients, and the aim of this study was to rectify this.

METHODS

A retrospective study of the course of jumper's knee in 100 athletes who presented to a sports medicine clinic over a nine year period was carried out. Subjects completed a questionnaire designed to collect details of sport participation, symptoms, and time out of sport. Ultrasonographic results were recorded from the radiologists' reports. Histopathological results were obtained for patients who had surgery.

RESULTS

Forty eight subjects recalled that symptoms of jumper's knee began before the age of 20 years. Symptoms prevented 33 from participating in sport for more than six months, and 18 of these were sidelined for more than 12 months. Forty nine of the subjects had two or more separate episodes of symptoms. Ultrasonography showed a characteristics hypoechoic region at the junction of the inferior pole of the patella and the deep surface of the patellar tendon. Histopathological examination showed separation and disruption of collagen fibres on polarisation light microscopy and an increase in mucoid ground substance consistent with damage of tendon collagen without inflammation.

CONCLUSIONS

Jumper's knee has the potential to be a debilitating condition for a sports person. About 33% of athletes presenting to a sports medicine clinic with jumper's knee were unable to return to sport for more than six months.

Relationship between symptoms of jumper's knee and the ultrasound characteristics of the patellar tendon among high level male volleyball players

This study assessed the ultrasound characteristics of the patellar tendon in two groups of volleyball players, one group without knee symptoms and one group with symptoms of jumper's knee. Of 47 male elite players, 25 were diagnosed to have current and seven to have had previous symptoms of jumper's knee, as determined by clinical examination. Since some players had bilateral problems, there were 34 knees with current problems and nine with previous problems. Seven of the 30 knees with a clinical diagnosis of jumper's knee in the patellar tendon had normal ultrasound findings, and ultrasound changes believed to be associated with jumper's knee (tendon thickening, echo signal changes, irregular paratenon appearance) were observed in 12 of 51 knees without symptoms. Specific ultrasound findings such as paratenon changes, hypoechoic zones or pathological tendon thickness proximally did not correlate significantly with the degree or the duration of symptoms. This study suggests that the specificity and sensitivity of ultrasonography is low in the evaluation of patients with mild symptoms of jumper's knee.

Characteristics of the leg extensors in male volleyball players with jumper's knee

The aim of the present study was to characterize the performance ability of the leg extensor apparatus in a group of athletes with jumper's knee and to compare the results with those of a matched control group without knee symptoms. Patient and control groups (12 players in each) were selected from a population of 141 well-trained male Norwegian volleyball players, of which 55 (39%) satisfied the diagnostic criteria for jumper's knee. The testing program consisted of a standing jump, a countermovement jump, a 15-second rebound jump test, a standing jump with a 20-kg load, and a standing jump with a load corresponding to one-half of the subject's body weight. Jump height and power were measured using a contact mat connected to an electronic timer. The test results of the patient group were significantly higher than those of the control group for the countermovement jump (15% increase), power during rebound jump (41%), work done in standing jump (12%) and countermovement jump (22%), and the difference between countermovement jump and standing jump (effect of adding eccentric component). Athletes with jumper's knee demonstrated better performance in jump tests than uninjured athletes, particularly in ballistic jumps involving eccentric force generation.

Diagnosis and treatment of stress fracture of the patella in athletes

Five cases of stress fracture of the patella in athletes are presented. Four of these occurred transversally in the lower part and one longitudinally in the lateral part of the patella. Three of the patients were females (endurance runner, high jumper, and orienteerer) and two males (volleyball and soccer player). The diagnosis was made 2-8 months from the onset of the symptoms. Conservative treatment was successful in only one patient; all others were treated surgically, with good end result. Drilling of the fracture line was performed twice with metal wire cerclage fixation, excision of the lateral fragment was carried out once, and a bone graft with K wires and cerclage compression (tension band) was performed once. In all cases the patellar retinaculum was intact, indicating a stress injury. Stress fracture of the patella is a rare overuse injury, and therefore difficulties and delays in the diagnosis and treatment may occur. In cases with delayed diagnosis we recommend operative treatment.