Intratendinous Injection of Hyaluronate Induces Acute Inflammation: A Possible Detrimental Effect

Combined ultrasound guided peritendinous hyaluronic acid (500-730 Kda) injection with extracorporeal shock waves therapy vs. extracorporeal shock waves therapy-only in the treatment of shoulder pain due to rotator cuff tendinopathy. A randomized clinical trial

BACKGROUND

Rotator cuff tendinopathy (RCTe) is the most common cause of pain and shoulder dysfunction. Numerous clinical studies have demonstrated the therapeutic capacity of exogenous peritendinous hyaluronic acid (HA), and the effectiveness of extracorporeal shockwaves therapy (ESWT) in reducing pain. The aim of this study was to evaluate the added effects of HA treatment plus ESWT (E-g) or ESWT alone (SC-g), focusing on reduction of self-reported pain and disability of patients with RCTe.

METHODS

Monocentric, randomized open-label clinical trial. Patients' selection, enrollment and interventions were conducted at the Chiparo Physical Medicine and Rehabilitation outpatient facility (Lecce, Italy). Patients with a diagnosis of RCTe, were randomly allocated to the E-g or to the SC-g. Participants were assessed for self-perceived pain, and for disability, at baseline, after 30 and 60 days.

RESULTS

Forty adults (mean age 50.8±6.3; 23 woman, 17 men) were enrolled in the study, twenty for each group. During the study, both groups improved their perceived level of disability of the arm (-25.01±2.79; P<0.001), and for pain (-3.13±0.50; P<0.001). A multiplicative effect was demonstrated in the time × treatment interaction for disability (beta±SE beta: 7.40±1.77; P<0.001), and pain (beta±SE beta: 0.95±0.32; P<0.001). Moreover, more patients in the E-g reached the MCID in the outcomes-score compared to SC-g. Lastly, number needed to treat were calculated, for disability: NNT=2 (95% CI: 1-3), and for pain-score: NNT=1 (95% CI: 1-2).

CONCLUSIONS

This study provides preliminary evidence that, compared to ESWT alone, the combining ESWT and peritendinous HA-injections, revert disability and reduces shoulder pain faster in patients with RCTe.

Comparison of single platelet-rich plasma injection with hyaluronic acid injection for partial-thickness rotator cuff tears

BACKGROUND

Partial-thickness rotator cuff tears (PTRCTs) is not uncommon, and various nonsurgical injection therapy for PTRCTs emerged. Platelet-rich plasma (PRP) and hyaluronic acid (HA) injection were proposed for treating PTRCTs; however, the relation of dose among injectates was still lacking.

METHODS

This was a prospective, nonrandomized, comparative study. The aim of the study was to compare the effects of ultrasound-guided single PRP injection with three doses of HA injection, combination of postinjection rehabilitation, for treating PTRCTs. Subjects received either ultrasound-guided PRP injection and rehabilitation exercise, or ultrasound-guided subacromial HA injection and rehabilitation exercise. Shoulder Pain and Disability Index (SPADI), range of motion (ROM), pain visual analog scale (VAS), and Constant-Murley Shoulder Score (CMSS) were recorded before injection, and at 1 and 3 months after injection.

RESULTS

Forty-eight patients were enrolled. They received either ultrasound-guided single PRP (n = 24) intralesional and peritendinous injection or three doses of HA (n = 24) subacromial injection plus rehabilitation exercise. In the PRP group, SPADI scores, VAS scores, CMSS significantly improved at 1-month and 3-month follow up; flexion and abduction ROM significantly increased at 3-month follow up. In the HA group, SPADI scores, VAS during overhead activities, VAS night pain, and CMSS significantly improved in the first and third months; flexion and active abduction ROM significantly increased in the third month. The PRP group revealed significantly better passive abduction ROM and CMSS at third month than HA group.

CONCLUSION

Ultrasound-guided single PRP injection exhibited comparable benefit to three doses of HA injection in patients with PTRCTs short-termly, with an extended effect regarding passive shoulder abduction ROM and CMSS.

Thermal pretreatment promotes the protective effect of HSP70 against tendon adhesion in tendon healing by increasing HSP70 expression

Tendon adhesion is a substantial challenge for tendon repair. Thermal pretreatment (TP) may decrease inflammation by upregulating heat shock proteins (HSPs). The present study intends to identify the function that TP serves when combined with HSP70 overexpression in tendon healing and adhesion in rats. Sprague‑Dawley male rats were used to establish a surgically ablative tendon postoperative suture model, and the positive expression of the HSP70 protein was measured using immunohistochemistry. Changes to the blood vessels and collagenous fiber, in addition to the maximum tensile strength and the tendon sliding distance, were detected under a microscope. Finally, HSP70, tumor growth factor β (TGF‑β), and insulin‑like growth factor 1 (IGF‑1) mRNA and protein levels were all determined by employing reverse transcription‑quantitative polymerase chain reaction and western blot analysis methods. The positive expression of the HSP70 protein increased following TP. Furthermore, TP reduced the infiltration of inflammatory cells and improved the collagenous arrangement, accompanied by an increased maximum tensile force and tendon gliding distance following surgery. In addition, TP increased the mRNA and protein expression levels of HSP70, TGF‑β and IGF‑1. Altogether, TP increases HSP70 expression, thereby reducing postoperative traumatic inflammation and establishing tendon adhesion and promoting tendon healing. Thus, TP may be a potential strategy for the treatment of tendon adhesion.

Hyaluronic Acid

In recent times, the field of tissue engineering and regenerative medicine (TERM) has considerably increased the extent of therapeutic strategies for clinical application in orthopedics. However, TERM approaches have its rules and requirements, in the respect of the biologic response of each tissue and bioactive agents which need to be considered, respected, and subject of ongoing studies. Different medical devices/products have been prematurely available on the market and used in clinics with limited success. However, other therapeutics, when used in a serious and evidence-based approach, have achieved considerable success, considering the respect for solid expectations from doctors and patients (when properly informed).Orthobiologics has appeared as a recent technological trend in orthopedics. This includes the improvement or regeneration of different musculoskeletal tissues by means of using biomaterials (e.g., hyaluronic acid), stem cells, and growth factors (e.g., platelet-rich plasma). The potential symbiotic relationship between biologic therapies and surgery makes these strategies suitable to be used in one single intervention.However, herein, the recent clinical studies using hyaluronic acid (HA) in the treatment of orthopedic conditions will mainly be overviewed (e.g., osteochondral lesions, tendinopathies). The possibilities to combine different orthobiologic agents as TERM clinical strategies for treatment of orthopedic problems will also be briefly discussed.

Characteristics of Sonography in a Rat Achilles Tendinopathy Model: Possible Non-invasive Predictors of Biomechanics

The purpose of this study was to investigate the dynamic changes of histopathology, biomechanical properties, echo intensity, and ultrasound features in a collagenase-induced tendinopathy model of rat Achilles tendons, and to examine the associations among biomechanical properties, echo intensity, and ultrasound features. Forty-two rats received an ultrasound-guided collagenase injection on their left Achilles tendons, and needle puncture on the right ones as the control. At four, eight, and twelve weeks post-injury, the tendons were examined via measurements of their biomechanical properties, histopathological and ultrasonographic characteristics. The injured tendons showed significantly higher histopathological scores, lower Young’s modulus, and higher ultrasound feature scores than the those of control ones throughout the study period. Up to week 12, all injured tendons showed defective healing. The neovascularization score had a significant negative linear association with the failure stress and Young’s modulus. Maximum normalized echo intensity had a significant positive linear association with maximum strain. Therefore, neovascularization and maximum normalized echo intensity are associated with mechanically altered tendinopathic tendons. Non-invasive ultrasound methodology, including echo intensity and ultrasound feature scores, may provide useful information about biomechanical properties of tendinopathic tendons.