Effect of injected versus iontophoretic corticosteroid on the rabbit tendon

Effects of Ultrasound-Guided Peritendinous and Intrabursal Corticosteroid Injections on Shoulder Tendon Elasticity: A Post Hoc Analysis of a Randomized Controlled Trial

OBJECTIVES

The study aimed to investigate whether the shoulder tendons changed their elasticity after ultrasound-guided peritendinous or intrabursal corticosteroid injections.

DESIGN

Post hoc secondary analysis of a double-blinded, randomized controlled study with 3 months of follow-up.

SETTING

Outpatient rehabilitation clinic.

PARTICIPANTS

Patients with subacromial impingement syndrome (N=60).

INTERVENTIONS

Patients with unilateral shoulder pain were randomly assigned to receive standard ultrasound-guided subacromial or dual-target corticosteroid injections. The supraspinatus tendons were exposed to 40 mg triamcinolone acetonide in the formal group, whereas the long head of the biceps brachii tendons (LHBT) and supraspinatus tendons were individually infiltrated by 20 mg triamcinolone acetonide in the latter group. Patients' bilateral shoulders were divided into group 1 (n=30, receiving standard subacromial injections), group 2 (n=30, receiving dual-target injections), and group 3 (n=60, without injections).

MAIN OUTCOME MEASURES

Strain ratio of LHBT and supraspinatus tendons using ultrasound elastography.

RESULTS

The repeated-measures analysis of variance revealed no intragroup difference of the strain ratio of the LHBT (P=.412 for group 1, P=.936 for group 2, P=.131 for group 3) and supraspinatus tendon (P=.309 for group 1, P=.067 for group 2, P=.860 for group 3) across the 3 time points. Treating group 3 as the reference, the linear mixed model revealed no significant changes in tendon elasticity after either the standard subacromial injection (P=.205 for the LHBT and P=.529 for the supraspinatus tendon) or the dual-target injection (P=.961 for the LHBT and P=.831 for the supraspinatus tendon).

CONCLUSIONS

Elasticity of the LHBT and supraspinatus tendons is unlikely to change after a single dose of peritendinous or intrabursal corticosteroid injections. Future studies with a shorter follow-up interval are needed to validate whether corticosteroid injections can cause transient changes of the tendon's elasticity.

Achilles Tendinopathy and Associated Disorders

Degenerative disorders of the Achilles tendon are common, affecting up to 18% of the adult population. A thorough evaluation including a focused history, physical examination, and diagnostic studies helps in choosing the appropriate treatment. Initial treatment is usually nonoperative, consisting of activity modification, bracing, and physical therapy. Patents who fail nonoperative management may be treated operatively with a wide range of procedures from endoscopic surgery to open debridement and tendon transfer. Understanding a patient’s expectations and educating patients about potential treatments and their outcomes enables informed collaborative decision making. This article will review the evaluation and management Achilles tendinopathy and associated disorders.

The risks and benefits of glucocorticoid treatment for tendinopathy: a systematic review of the effects of local glucocorticoid on tendon

OBJECTIVE

Our primary objective was to summarise the known effects of locally administered glucocorticoid on tendon tissue and tendon cells.

METHODS

We conducted a systematic review of the scientific literature using the PRISMA and Cochrane guidelines of the Medline database using specific search criteria. The search yielded 50 articles, which consisted of 13 human studies, 36 animal studies and one combined human/animal study.

RESULTS

Histologically, there was a loss of collagen organisation (6 studies) and an increase in collagen necrosis (3 studies). The proliferation (8 studies) and viability (9 studies) of fibroblasts was reduced. Collagen synthesis was decreased in 17 studies. An increased inflammatory cell infiltrate was shown in 4 studies. Increased cellular toxicity was demonstrated by 3 studies. The mechanical properties of tendon were investigated by 18 studies. Descriptively, 6 of these studies showed a decrease in mechanical properties, 3 showed an increase, while the remaining 9 showed no significant change. A meta-analysis of the mechanical data revealed a significant deterioration in mechanical properties, with an overall effect size of -0.67 (95% CI = 0.01 to -1.33) (data from 9 studies).

CONCLUSIONS

Overall it is clear that the local administration of glucocorticoid has significant negative effects on tendon cells in vitro, including reduced cell viability, cell proliferation and collagen synthesis. There is increased collagen disorganisation and necrosis as shown by in vivo studies. The mechanical properties of tendon are also significantly reduced. This review supports the emerging clinical evidence that shows significant long-term harms to tendon tissue and cells associated with glucocorticoid injections.

Dextrose prolotherapy and corticosteroid injection into rat Achilles tendon

PURPOSE

To assess the mechanical behavior and the histology of collagen fibers after prolotherapy with 12.5% dextrose into rat Achilles tendons and to compare with those of corticosteroid treatment.

METHODS

Out of 60 adult female Wistar rats (70 tendons), 15 received 12.5% dextrose (group I); 15 were treated with corticosteroid injection (group II); and 15 were given 0.9% saline injection (group III), all into the right Achilles tendon, whereas 13 animals received no injections (group IV). Three doses of each substance (groups I, II, and III) were given at a 5-day interval. Collagen fiber color was quantitatively assessed in three samples from each group and in five samples from the control group using picrosirius red staining under polarized and nonpolarized light. Twelve tendons from each group treated with the test substance and 20 tendons from the control group were submitted to the tensile strength test.

RESULTS

There was no statistical difference across the groups with respect to maximum load at failure (n.s.) and absorbed energy (n.s.). With respect to tendon rupture, there was no difference between the myotendinous and the tendinous regions (n.s.). However, hematoxylin-eosin staining revealed statistical significance in lymphocytic inflammatory infiltrate (P = 0.008) and in parallel fiber orientation (P = 0.003) when comparing groups to the control group, without significance for either neovascularization (n.s.) or the presence of fibroblasts (n.s.). Likewise, there was no significant difference between the percentage of mature (n.s.) and immature (n.s.) fibers.

CONCLUSIONS

Dextrose was not deleterious to the tendinous tissue, as it did not change the mechanical and histological properties of Achilles tendons in rats. The data obtained in this study may help clinicians in their daily work as they suggest that injections of 12.5% dextrose caused no harm to the tendons, although the clinical importance in humans still needs to be defined.

Corticosteroid injections in the treatment of foot & ankle disorders: an AOFAS survey

BACKGROUND

Evidence-based guidelines for the use of injectable corticosteroids are lacking, and the true incidence of complications is unknown.

MATERIALS AND METHODS

The 2007--2008 AOFAS membership (969 members) was electronically queried to identify corticosteroid injection practices for certain clinical entities and rates of complications. One hundred ninety-seven surveys were returned. Eleven clinical diagnoses were evaluated for number of injections per year per respondent, rate of injection, plans to change injection pattern, and use of immobilization. Thirteen possible complications were analyzed for observed frequencies and total number of complications.

RESULTS

Those in practice less than 5 years showed the lowest rate of injections at 14.1 per month, which increased to 26.1 for those in practice 6 to 10 years. An overall average of 20.6 injections per month per clinician was reported. Injections for midsubstance Achilles tendinopathy was largely avoided as demonstrated by a 98% no-inject rate. Insertional Achilles tendonitis was similar, albeit lower with an 88% no-inject rate. Non-Achilles tendonitis showed a varied response for injections. Posterior tibial tendonitis was injected 26% of the time, whereas peroneal tendonitis was injected 54% of the time. Complications including skin depigmentation were observed most frequently (5.1%), followed by atrophy (4%), flare reaction (3.5%), MTPJ dislocation (2.7%), plantar fascia rupture (1.5%), and heel pad atrophy (1.4%).

CONCLUSION

Despite many case reports of complications, our survey indicates that the incidence of complications was perceived to be low and generally related to the injection site (skin depigmentation, atrophy, flare reaction).

Soft tissue injections in the athlete

BACKGROUND

Injections into or adjacent to soft tissue structures, including muscle, tendon, bursa, and fascia, for pain relief and an earlier return to play have become common in the field of sports medicine.

STUDY DESIGN

Clinical review.

RESULTS

Corticosteroids, local anesthetics, and ketorolac tromethamine (Toradol) are the most commonly used injectable agents in athletes. The use of these injectable agents have proven efficacy in some disorders, whereas the clinical benefit for others remain questionable. All soft tissue injections performed for pain control and/or an anti-inflammatory effect have potentially serious side effects, which must be considered, especially in the pregame setting.

CONCLUSIONS

The primary concern regarding corticosteroid and local anesthetic injections is an increased risk of tendon rupture associated with the direct injection into the tendon. Intramuscular Toradol injections provide significant analgesia, as well as an anti-inflammatory effect via its inhibitory effect on the cyclooxygenase pathway. The risk of bleeding associated with Toradol use is recognized but not accurately quantified.

The effects of intratendinous and retrocalcaneal intrabursal injections of corticosteroid on the biomechanical properties of rabbit Achilles tendons

BACKGROUND

The use of corticosteroid injections in the treatment of retrocalcaneal bursitis is controversial. We assessed the effects of corticosteroid injections, both within the tendon substance and into the retrocalcaneal bursa, on the biomechanical properties of rabbit Achilles tendons. The systemic effects of bilateral corticosteroid injections were also studied.

METHODS

The rabbits were divided into three treatment groups. The rabbits in Group I received injections of corticosteroid into the Achilles tendon on the left side and injections of normal saline solution into the Achilles tendon on the right, those in Group II received injections of corticosteroid into the retrocalcaneal bursa on the left side and injections of saline solution into the Achilles tendon on the right, and those in Group III received injections of corticosteroid into the Achilles tendon on the left side and injections of corticosteroid into the retrocalcaneal bursa on the right. These injections were given weekly for three weeks. At four weeks after the final injection, the tendons were harvested and were tested biomechanically to determine failure load, midsubstance strain and total strain, modulus of elasticity, failure stress, and total energy absorbed. The site of failure was also documented. The groups were compared according to the location of the injections, the type of injection (steroid or saline solution), and the total systemic load of steroid.

RESULTS

Specimens from limbs that had received intratendinous injections of corticosteroid showed significantly decreased failure stress compared with those from limbs that had received intratendinous injections of saline solution (p = 0.008). Specimens from limbs that had received intrabursal injections of corticosteroid demonstrated significantly decreased failure stress (p = 0.05), significantly decreased total energy absorbed (p = 0.017), and significantly increased total strain (p = 0.049) compared with specimens from limbs that had received intratendinous injections of saline solution. Specimens from limbs that had received intratendinous injections of corticosteroid were biomechanically equivalent to specimens from limbs that had received intrabursal injections of corticosteroid. Specimens from rabbits that had received bilateral injections of corticosteroid demonstrated significantly decreased failure load (p = 0.011), modulus of elasticity (p = 0.015), failure stress (p = 0.03), and total energy absorbed (p = 0.015) compared with those from rabbits that had received unilateral injections of steroid.

CONCLUSIONS

Local injections of corticosteroid, both within the tendon substance and into the retrocalcaneal bursa, adversely affected the biomechanical properties of rabbit Achilles tendons. Additionally, tendons from rabbits that had received bilateral injections of corticosteroid demonstrated an additive adverse effect, with significantly worse biomechanical properties compared with tendons from rabbits that had received unilateral injections of corticosteroid.

Fluoroscopically guided low-volume peritendinous corticosteroid injection for Achilles tendinopathy. A safety study

BACKGROUND

The safety and efficacy of corticosteroid injection for the treatment of Achilles tendinopathy is not known, with some reports indicating the hazard of tendon rupture and others extolling the efficacy of such injections. This study was undertaken to assess the safety of fluoroscopically guided corticosteroid injections into the peritendinous space for the treatment of Achilles tendinopathy.

METHODS

A series of patients was treated with fluoroscopically guided corticosteroid injections into the space surrounding the Achilles tendon. Major and minor complications were recorded, as were the number of repeat injections, the duration of symptomatic relief attained with the injection, and a subjective rating of symptoms related to the Achilles tendon.

RESULTS

Of eighty-three patients who had been treated, seventy-eight were available for follow-up and forty-three met our requirement for a minimum two-year follow-up (average duration of follow-up, 37.4 months). No major complications and one minor complication occurred in the forty-three patients. Seventeen (40%) of the patients reported improvement after the procedure, twenty-three (53%) thought that their condition was unchanged, and three (7%) felt that their condition was worse than it had been prior to the injection.

CONCLUSIONS

This retrospective cohort study establishes the safety of low-volume injections of corticosteroids for the treatment of Achilles tendinopathy when the needle is carefully inserted into the peritendinous space under direct fluoroscopic visualization.

Effect of vascular endothelial growth factor on rat Achilles tendon healing

This study evaluated the effect of exogenous vascular endothelial growth factor (VEGF) on tendon healing and regulation of other growth factors in a rat Achilles tendon model. Fifty Sprague-Dawley rats were used. In the experimental group, the left Achilles tendon was transected and repaired with the modified Kessler suture technique, and the right Achilles tendon was transected and repaired with resection of plantaris tendon. VEGF, 100 mul (50 mug/ml), was injected into each tendon at the repair site. The same surgical procedures were performed in the control group, with the same volume of saline injected into the repair sites. At intervals of 1, 2, and 4 weeks, the animals were killed and the tendons were harvested and evaluated for tensile strength (1, 2, and 4 weeks) and gene expression (postoperative day 4). At 1 week postoperatively, when plantaris tendon was preserved, the tensile strength of the repaired tendons with VEGF treatment (3.63 +/- 0.62 MPa) was significantly higher than the tensile strength of the repaired tendons with saline treatment (2.20 +/- 0.36 MPa). There was no difference in tensile strength between the two groups without the plantaris tendon support. At 2 weeks postoperatively, the tensile strength was 11.34 +/- 3.89 MPa in the group with VEGF treatment and plantaris tendon preservation, which was significantly higher than the tensile strength in the other groups. There was no significant difference in tensile strength among the groups at 4 weeks postoperatively. The gene expression showed that transforming growth factor-beta in the VEGF-treated tendon was up-regulated in the early stage of tendon healing, whereas expression of platelet-derived growth factor, basic fibroblast growth factor, and insulin-like growth factor-1 was not significantly different among the groups. In conclusion, administration of exogenous VEGF can significantly improve tensile strength early in the course of the rat Achilles tendon healing and was associated with increased expression of transforming growth factor-beta.

Sports and other soft tissue injuries, tendinitis, bursitis, and occupation-related syndromes

This review highlights three areas: plantar fasciitis, Achilles tendinitis, and carpal tunnel syndrome. The diagnosis and treatment of plantar fasciitis are reviewed; nonsurgical treatments remain the mainstay of management. Several recent articles support the use of night splints. Some novel treatments recently investigated, including low intensity laser irradiation and extracorporeal shock wave lithotripsy, are reviewed, as well as the effectiveness of steroid injection. Novel treatments for Achilles tendinitis are also reviewed, including the use of injection therapy and the treatment approach of one author for the management of Achilles tendon rupture. Nonsurgical techniques in the treatment of carpal tunnel syndrome, such as yoga, ultrasound, noninvasive laser neurolysis, manipulation, nerve and tendon gliding exercises, and medications, are reviewed. Prednisolone was shown to be effective in the treatment of mild to moderate disease and nonsteroidal anti-inflammatory drugs were found to be ineffective.