Timing matters: NSAIDs interfere with the late proliferation stage of a repaired rotator cuff tendon healing in rats

Effect of post-operative NSAID use on rotator cuff repair outcomes

Background

The impact of non-steroidal anti-inflammatory drugs (NSAIDs) on rotator cuff repair is an ongoing area of study within orthopedics, with conflicting results in current literature. Despite concerns over the deleterious effects of NSAIDs on rotator cuff healing, they are becoming an integral part of a multimodal post-operative pain control regiment. The purpose of this study was to compare post-operative patient-reported outcomes (PROs), complications rates, and retear rates of arthroscopic rotator cuff repairs in patients using ibuprofen post-operatively to those who abstained from NSAIDs for six weeks after surgery. It was hypothesized that a short course of ibuprofen post-operatively would not lead to inferior PRO scores, increased retear rates, nor increased complication rates after arthroscopic rotator cuff repair.

Methods

Patients of the primary surgeon who underwent arthroscopic rotator cuff repair between 2012 and 2022 were evaluated by retrospective chart review. In May 2017 the primary surgeon changed his protocol from avoiding NSAIDs for six weeks after surgery to routinely prescribing two weeks of Ibuprofen 800 mg TID post-operatively. Patients who avoided NSAIDs for six weeks were compared to patients who were prescribed NSAIDs post-operatively. Patient demographic data, pre-operative MRI results, pre-operative and post-operative PROs were collected from the EMR. Additionally, post-operative complications and repair failures requiring reoperation within one year were evaluated.

Results

125 patients met inclusion criteria for this study with 36 patients in the NSAID group and 89 in the no NSAID group. When comparing improvement in PROs, the NSAID group reached MCID at one year in 83.8 % of patients and the no NSAID group reached MCID at one year in 73.9 % of patients. There was no significant difference between the groups in reaching MCID improvement at one year (p = 0.471). Five post-operative complications were reported in the no NSAID group and two in the NSAID group (5.7 % vs 5.4 %, respectively, p = 0.827). Finally, there was no significant difference in the percentage of post-operative rotator cuff repair failures requiring revision in the first year between the groups (2.3 % vs 2.7 %, p = 1.000).

Conclusion

There was no difference in percent of patients improving their PRO by the MCID between the groups that used ibuprofen and the group that did not. There was also no difference in post-operative complication rates and rates of symptomatic retear requiring reoperation between the groups. This supports that a short course of NSAIDs post-operatively, specifically ibuprofen, after rotator cuff repair does not increase reoperation rates nor lead to a clinically significant decrease in PROs at one year.

Biologics in rotator cuff repair

Rotator cuff tears are common in middle-aged and elderly patients. Despite advances in the surgical repair of rotator cuff tears, the rates of recurrent tear remain high. This may be due to the complexity of the tendons of the rotator cuff, which contributes to an inherently hostile healing environment. During the past 20 years, there has been an increased interest in the use of biologics to complement the healing environment in the shoulder, in order to improve rotator cuff healing and reduce the rate of recurrent tears. The aim of this review is to provide a summary of the current evidence for the use of forms of biological augmentation when repairing rotator cuff tears.

Non-steroidal Anti-inflammatory Drugs and Cyclooxygenase-2 Inhibitors Do Not Affect Healing After Rotator Cuff Repair: A Systematic Review and Meta-analysis

PURPOSE

To determine whether non-steroidal anti-inflammatory drugs (NSAIDs) and cyclooxygenase-2 (COX-2) inhibitors affect healing rate, functional outcomes, and patient satisfaction after rotator cuff repair.

METHODS

Medline, EMBASE, PsychINFO and the Cochrane Library were searched for randomized controlled trials (RCTs) investigating the use of NSAIDs and COX-2 inhibitors after arthroscopic rotator cuff repair. Primary outcomes included healing and retear rate, determined by radiological imaging. Secondary outcomes included shoulder-specific outcome measures and the visual analog scale (VAS). Risk of bias was graded using the Cochrane risk-of-bias v2.0 tool. The GRADE framework was used to assess certainty of findings.

RESULTS

Seven RCTs with a total of 507 patients were included (298 randomized to NSAID/COX-2 vs 209 randomized to control). NSAIDs use did not yield a difference in retear rate (P = .77). NSAIDs were shown to significantly reduce pain in the perioperative period (P = .01); however, no significant difference was present at a minimum of 6 months (P = .11). COX-2 inhibitors did not significantly reduce pain (P = .15). Quantitative analysis of ASES and UCLA scores showed NSAIDs significantly improved functional outcomes versus control (P = .004). COX-2 inhibitors did not significantly improve functional outcomes (P = .15). Two trials were deemed "low" risk of bias, four trials were graded to have "some concerns", and one trial was graded to have "high" risk of bias. Retear rate and functional PROMs were deemed to have "low" certainty. VAS pain scale was graded to have "moderate" certainty.

CONCLUSIONS

This systematic review and meta-analysis indicates that NSAIDs do not affect healing rate after arthroscopic rotator cuff repair, but they do significantly improve postoperative pain and functional outcomes. No significant difference was seen in pain or functional outcomes with the use of COX-2 inhibitors.

LEVEL OF EVIDENCE

Level I, meta-analysis of randomized controlled trials.

Effect of perioperative acetaminophen on pain management in patients undergoing rotator cuff repair: a prospective randomized study

BACKGROUND

Limiting opioid use in perioperative pain management is currently an important focus in orthopedic surgery. The ability of acetaminophen to reduce postoperative opioid consumption while providing acceptable pain management has not been thoroughly investigated in patients undergoing rotator cuff repair (RCR).

METHODS

Patients undergoing primary arthroscopic RCR were prospectively randomized to 1 of 3 treatment groups: Group 1 (control) received both 5 mg of oxycodone every 6 hours as needed and 1000 mg of acetaminophen orally every 6 hours as needed after surgery and had the option to take either medication or both. Group 2 (control) received only 5 mg of oxycodone every 6 hours as needed without any additional acetaminophen after surgery. Group 3 received 1000 mg of acetaminophen orally every 6 hours for 1 day prior to and after surgery, which was subsequently decreased to administration every 8 hours during postoperative days 2-5. Group 3 patients were also allowed to take 5 mg of oxycodone every 6 hours as needed after surgery. All patients received interscalene blocks with liposomal bupivacaine (Exparel). Opioid use, pain scores, side effects, and overall satisfaction were assessed daily for the first week after surgery.

RESULTS

A total of 57 patients (mean age, 57.8 ± 9.55 years) were included in this study. Baseline demographic characteristics including age, sex, and body mass index were similar between the groups (P > .05). Patients in group 3 took significantly fewer narcotics overall (P = .017) and took significantly fewer pills each day compared with group 2. Group 3 also reported significantly better overall pain control compared with the other groups (P = .040). There were no significant differences in overall patient satisfaction between the groups (P > .05). Additionally, there were no significant differences between groups regarding postoperative medication-associated side effects (P > .05).

CONCLUSION

Perioperative acetaminophen represents an important component of multimodal analgesia in appropriately selected patients undergoing shoulder surgery. In this study, the use of perioperative acetaminophen significantly decreased opioid consumption and improved overall pain control after primary arthroscopic RCR.

Meloxicam Inhibited the Proliferation of LPS-Stimulated Bovine Endometrial Epithelial Cells Through Wnt/β-Catenin and PI3K/AKT Pathways

Meloxicam is a non-steroidal anti-inflammatory drug and has been used to relieve pain and control inflammation in cows with metritis and endometritis. Meloxicam has been found to be effective in inhibiting tissue or cell growth when it is used as an anti-inflammatory therapy. However, the influence of meloxicam on bovine endometrial regeneration has not been reported. This study was to research the effect of meloxicam (0.5 and 5 μM) on the proliferation of primary bovine endometrial epithelial cells (BEECs) stimulated by Escherichia coli lipopolysaccharide. The cell viability, cell cycle, and cell proliferation were evaluated by Cell Counting Kit-8, flow cytometry, and cell scratch test, respectively. The mRNA transcriptions of prostaglandin-endoperoxide synthase 1 (PTGS1) and PTGS2, Toll-like receptor 4, and proliferation factors were detected using quantitative reverse-transcription polymerase chain reaction. The activations of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) and Wnt/β-catenin pathways were determined using western blot and immunofluorescence. As a result, co-treatment of meloxicam and lipopolysaccharide inhibited (P < 0.05) the cell cycle progression and reduced (P < 0.05) the cell healing rate and the mRNA level of proliferation factors as compared with the cells treated with lipopolysaccharide alone. Meloxicam decreased (P < 0.05) the lipopolysaccharide-induced PTGS2 gene expression. Neither lipopolysaccharide nor meloxicam changed PTGS1 mRNA abundance (P > 0.05). Meloxicam inhibited (P < 0.05) the lipopolysaccharide-activated Wnt/β-catenin pathway by reducing (P < 0.05) the protein levels of β-catenin, c-Myc, cyclin D1, and glycogen synthase kinase-3β and prevented the lipopolysaccharide-induced β-catenin from entering the nucleus. Meloxicam suppressed (P < 0.05) the phosphorylation of PI3K and AKT. In conclusion, meloxicam alone did not influence the cell cycle progression or the cell proliferation in BEEC but caused cell cycle arrest and inhibited cell proliferation in lipopolysaccharide-stimulated BEEC. This inhibitory effect of meloxicam was probably mediated by Wnt/β-catenin and PI3K/AKT pathways.

Healing rates after rotator cuff repair for patients taking either celecoxib or placebo: a double-blind randomized controlled trial

Background

Use of anti-inflammatory medications (NSAIDs) is an important component of multimodal pain control after orthopedic procedures to avoid opioid overutilization and abuse. However, the deleterious effects of NSAIDs on tendon healing are of particular concern in rotator cuff repair (RCR). The purpose of this study was to evaluate the effect of celecoxib or placebo on healing rates after RCR when administered in the perioperative and immediate postoperative period using MRI evaluation at one year postoperatively. A secondary aim was to determine whether clinical differences existed between patients with intact or non-intact repairs.

Methods

Patients aged ≤65 years with partial- or full-thickness rotator cuff tear (<25x25 mm) were randomized to receive celecoxib 400 mg or placebo 1 hour before the procedure and 200mg bid for 3 weeks postoperatively. All patients were treated as clinically indicated at the time of surgery and followed standard postoperative protocol. Repair integrity was evaluated with MRI using the Sugaya classification for repair integrity. Data were analyzed using multivariable logistic regression by intent to treat.

Results

Seventy-nine patients were enrolled; 21 were lost to follow-up, 6 did not have cuff repair, 5 were revised, and 2 declined follow-up, leaving 45 patients with one-year follow-up. Five of these patients did not complete MRI, leaving 40 patients for review. Eighteen of 20 patients (90%) who received celecoxib completed all doses of study medication as did 15 of 20 patients (75%) who received placebo. The patient groups were similar for demographics, clinical results, and healing rate. After adjusting for tear size, no statistically significant difference in healing rate was found between groups, with 10 of 20 celecoxib patients (50%) having intact repair at 1 year compared with 14 of 20 placebo patients (70%) (OR = 0.53, 95% CI: 0.14, 2.08, P = 0.35).

Conclusion

Half of the patients who received celecoxib had an intact repair compared with 70% intact repair for patients receiving placebo. Although not statistically significant in this small study, larger studies are needed to clarify this important clinical concern. The authors do not recommend use of celecoxib for postoperative pain control after RCR.

Engineered Cell Sheets for the Effective Delivery of Adipose-Derived Stem Cells for Tendon-to-Bone Healing

BACKGROUND

Efforts are being made to treat rotator cuff tears (RCTs) that exhibit poor healing and high retear rates. Tendon-to-bone healing using mesenchymal stem cells is being explored, but research is needed to establish effective delivery options.

PURPOSE

To evaluate the effects of an adipose-derived stem cell (ADSC) sheet on mesenchymal stem cell delivery for tendon-to-bone healing of a chronic RCT in rats and to demonstrate that ADSC sheets enhance tendon-to-bone healing.

STUDY DESIGN

Controlled laboratory study.

METHODS

Mesenchymal stem cells were obtained from rat adipose tissue, and a cell sheet was prepared using a temperature-responsive dish. To evaluate the efficacy of stem cells produced in a sheet for the lesion, the experiment was conducted with 3 groups: repair group, cell sheet transplantation after repair group, and cell sheet-only group. Histological, biomechanical, and micro-computed tomography (micro-CT) results were compared among the groups.

RESULTS

Hematoxylin and eosin staining for histomorphological analysis revealed that the cell sheet transplantation after repair group (5.75 ± 0.95) showed statistically significant higher scores than the repair (2.75 ± 0.50) and cell sheet-only (3.25 ± 0.50) groups (P < .001). On safranin O staining, the cell sheet transplantation after repair group (0.51 ± 0.04 mm²) had a larger fibrocartilage area than the repair (0.31 ± 0.06 mm²) and cell sheet-only (0.32 ± 0.03 mm²) groups (P = .001). On micro-CT, bone volume/total volume values were significantly higher in the cell sheet transplantation after repair group (23.98% ± 1.75%) than in the other groups (P < .039); there was no significant difference in the other values. On the biomechanical test, the cell sheet transplantation after repair group (4 weeks after repair) showed significantly higher results than the other groups (P < .005).

CONCLUSION

Our study shows that engineered stem cells are a clinically feasible stem cell delivery tool for rotator cuff repair.

CLINICAL RELEVANCE

This laboratory study provides evidence that ADSCs are effective in repairing RCTs, which are common sports injuries.

Biologics

Biologics are a growing field that has shown immense promise for the treatment of musculoskeletal conditions both in orthopedic sports medicine and interventional pain management. These procedures utilize injection of supraphysiologic levels of platelets and growth factors to invoke the body's own inflammatory cascade to augment the healing of many bony and soft tissue conditions. While many patients improve with conservative care, there is a need to address the gap between those that improve with rehabilitation alone and those who ultimately require operative management. Orthobiologic procedures have the potential to fill this void. The purpose of this review is to summarize the basic science, evidence for use, and post-injection rehabilitation concepts of platelet-rich plasma (PRP) and mesenchymal stromal cells (MSCs) as they pertain to joints, tendons, ligaments, and the spine.

Nonsteroidal Anti-Inflammatory Drugs (NSAIDs) and Their Effect on Musculoskeletal Soft-Tissue Healing: A Scoping Review

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) are being increasingly employed as a part of multimodal non-opioid strategies to treat postoperative pain. In the present study, we sought to review the effects of short-term NSAID use on musculoskeletal soft-tissue healing.

METHODS

We performed a scoping review of all studies that included the use of NSAIDs and their effect on healing of soft tissues, which for the purpose of this review refers to non-osseous musculoskeletal tissue such as ligament, tendon, labrum, and meniscus. The inclusion criteria encompassed all studies (human, animal, and in vitro) that evaluated the effect of NSAIDs on soft-tissue healing. Subgroup analyses, wherever applicable, were conducted on the basis of the type of NSAID (cyclooxygenase [COX]-specific or nonspecific) and the type of study (human, animal, or in vitro). Relevant metadata from each study were abstracted, and descriptive statistics were used to summarize the results.

RESULTS

A total of 44 studies met the inclusion criteria, including 3 human studies, 33 animal studies, and 8 in vitro studies. These studies included 4 different NSAIDs in the human subgroup, 16 different NSAIDs in the animal subgroup, and 7 different NSAIDs in the in vitro subgroup. The majority of reported studies (including 1 of 2 human studies, 10 of 14 animal studies, and 3 of 3 in vitro studies) demonstrated that COX-2-selective inhibitors had negative impact on soft-tissue healing. In contrast, the majority of human and animal studies (2 of 2 and 19 of 30, respectively) demonstrated that nonselective COX inhibitors had no negative effect on the healing of labrum, tendons, and ligaments. The majority of in vitro studies demonstrated that NSAIDs have a harmful effect on biological processes involved in tendon-healing and regeneration (tenocyte proliferation, collagen and glycosaminoglycan synthesis).

CONCLUSIONS

Current limited evidence demonstrates that selective COX-2 inhibitors can negatively affect healing of musculoskeletal soft tissue after surgical repair. In contrast, the majority of studies demonstrate that nonselective COX inhibitors have no negative effect on musculoskeletal soft-tissue healing. Additional high-quality human clinical trials are necessary to provide more definitive conclusions.

Rebuilding Tendons: A Concise Review on the Potential of Dermal Fibroblasts

Tendons are vital to joint movement by connecting muscles to bones. Along with an increasing incidence of tendon injuries, tendon disorders can burden the quality of life of patients or the career of athletes. Current treatments involve surgical reconstruction and conservative therapy. Especially in the elderly population, tendon recovery requires lengthy periods and it may result in unsatisfactory outcome. Cell-mediated tendon engineering is a rapidly progressing experimental and pre-clinical field, which holds great potential for an alternative approach to established medical treatments. The selection of an appropriate cell source is critical and remains under investigation. Dermal fibroblasts exhibit multiple similarities to tendon cells, suggesting they may be a promising cell source for tendon engineering. Hence, the purpose of this review article was in brief, to compare tendon to dermis tissues, and summarize in vitro studies on tenogenic differentiation of dermal fibroblasts. Furthermore, analysis of an open source Gene Expression Omnibus (GEO) data repository was carried out, revealing great overlap in the molecular profiles of both cell types. Lastly, a summary of in vivo studies employing dermal fibroblasts in tendon repair as well as pilot clinical studies in this area is included. Altogether, dermal fibroblasts hold therapeutic potential and are attractive cells for rebuilding injured tendons.

The effect of high-intensity versus low-level laser therapy in the management of plantar fasciitis: randomized participant blind controlled trial

Objectives:

To evaluate and compare the efficacy of high-intensity laser therapy (HILT) and low-level laser therapy (LLLT) for plantar fasciitis.

Design:

A participant blind randomized controlled trial with parallel group design and an active comparator with follow-up at four weeks.

Settings:

Outpatient, University hospital.

Subjects:

Unilateral plantar fasciitis participants (n = 102) were randomly assigned into two groups. Recruitment period was from January 2017 to April 2019.

Interventions:

Interventions included eight sessions of laser therapy over three weeks and single session of patient education. The HILT group (n = 51) received HILT and the LLLT group (n = 51) received LLLT.

Main measures:

Primary outcomes: visual analogue scale; secondary outcomes: pressure algometry, sonography of plantar fascia thickness (time frame: baseline to three-week and four-week follow-up) and numeric rating scale (0%–100%) for opinion of participants on effect of treatment (time frame: three weeks). Data presented: mean (SD) or n (%).

Results:

There was no statistically significant difference between the groups according to visual analogue scale (pain in general reduction in three weeks: 2.57(3.45) vs. 2.88(3.28) cm), pressure algometry (pain threshold difference between healthy and affected heel reduction in three weeks: 1.80(6.39) vs. 1.77(2.85) kg) and sonography measurements (plantar fascia thickness difference between healthy and affected heel reduction in three weeks: 0.19(0.56) vs. 0.30(0.57) mm). There was a statistically significant difference between the groups in participants’ opinion in favor to HILT group (efficacy of treatment better than 50%: 26(51%) vs. 37(73%)).

Conclusion:

No statistically significant difference between groups was observed.

Post-operative non-steroidal anti-inflammatory drugs do not affect clinical outcomes of rotator cuff repair

Background

The administration of non-steroidal anti-inflammatory drugs (NSAIDs) to patients is thought to impair rotator cuff healing and clinical outcomes.

Methods

36 patients who underwent rotator cuff repair were divided into 3 groups based on their post-operative analgesia regimes.

Results

At 4.4 years postoperative, there was significant improvement in SST and UCLA scores (p < 0.001). There were no significant differences in post-operative clinical outcome scores between the groups (p > 0.05). Administration of NSAIDs and duration of their use did not influence outcomes of rotator cuff repair (p = 0.151).

Conclusion

NSAIDs has no significant influence on clinical outcomes of rotator cuff repair.

Biologics and stem cell-based therapies for rotator cuff repair

The rotator cuff is composed of several distinct muscles and tendons that function in concert to coordinate shoulder motion. Injuries to these tendons frequently result in permanent dysfunction and persistent pain. Despite considerable advances in operation techniques, surgical repair alone still does not fully restore rotator cuff function. This review focuses on recent research in the use of biologics and stem cell-based therapies to augment repair, highlighting promising avenues for future work and remaining challenges. While a number of animal models are used for rotator cuff studies, the anatomy of the rotator cuff varies dramatically between species. Since the rodent rotator cuff shares the most anatomical features with the human, this review will focus primarily on rodent models to enable consistent interpretation of outcome measures.

The role of rehabilitation after regenerative and orthobiologic procedures for the treatment of tendinopathy: a systematic review

Aim: Significant variability exists in the literature, with no clear consensus to the optimal protocol after a regenerative procedure. Given this uncertainty, the authors systematically reviewed the literature cataloging the different variables that may influence outcomes. Methods: Search was limited to randomized clinical trials and prospective cohort studies of regenerative procedures for the treatment of tendinopathy. Variables were predetermined, and included: cyrotherapy, pre- and post-procedure nonsteroidal anti-inflammatory drugs use, recommendations for alternative pain medications, immobilization and duration of rest. Variables were categorized based on the influence of the intervention on the three phases of healing. Results: 749 studies were assessed for eligibility, and 60 studies were included. Significant variability existed in the literature. Conclusion: Despite the importance of rehabilitation after regenerative procedures, there is a paucity of evidence available to guide clinicians and highlights the need for additional validation.

Regenerative Engineering of the Rotator Cuff of the Shoulder

Rotator cuff tears often heal poorly, leading to re-tears after repair. This is in part attributed to the low proliferative ability of the resident cells (tendon fibroblasts and tendon-stem cells) upon injury to the rotator cuff tissue and the low vascularity of the tendon insertion. In addition, surgical outcomes of current techniques used in clinical settings are often suboptimal, leading to the formation of neo-tissue with poor biomechanics and structural characteristics, which results in re-tears. This has prompted interest in a new approach, which we term as "Regenerative Engineering", for regenerating rotator cuff tendons. In the Regenerative Engineering paradigm, roles played by stem cells, scaffolds, growth factors/small molecules, the use of local physical forces, and morphogenesis interplayed with clinical surgery techniques may synchronously act, leading to synergistic effects and resulting in successful tissue regeneration. In this regard, various cell sources such as tendon fibroblasts and adult tissue-derived stem cells have been isolated, characterized, and investigated for regenerating rotator cuff tendons. Likewise, numerous scaffolds with varying architecture, geometry, and mechanical characteristics of biologic and synthetic origin have been developed. Furthermore, these scaffolds have been also fabricated with biochemical cues (growth factors and small molecules), facilitating tissue regeneration. In this Review, various strategies to regenerate rotator cuff tendons using stem cells, advanced materials, and factors in the setting of physical forces under the Regenerative Engineering paradigm are described.

Leading the Way to Solutions to the Opioid Epidemic: AOA Critical Issues

BACKGROUND

In the past 2 decades, overdoses and deaths from prescription opioids have reached epidemic proportions in the United States. The widespread use of opioids complicates management of the orthopaedic surgery patient in the acute and chronic settings. Orthopaedic surgeons are some of the top prescribers of opioids in the complex setting of chronic use, abuse, and diversion.

METHODS

The literature regarding the basic science of pharmacologic options for pain management (e.g., opioids and nonsteroidal anti-inflammatory drugs), the impact of strategies on bone and soft-tissue healing, and pain relief are summarized as they relate to the management of orthopaedic injuries and conditions. Additionally, a section on designing solutions to address the current opioid crisis is presented.

RESULTS

The mechanism of action of different classes of analgesic medications is discussed, as well as the basic scientific evidence regarding the impact of narcotic and nonnarcotic analgesic medications on bone-healing and on other organ systems. Differences between pain and nociception, various treatment strategies, and clinical comparisons of the effectiveness of various analgesics compared with opioids are summarized. Finally, options for addressing the opioid crisis, including the description of a large system-wide intervention to impact prescriber behavior at the point of care using health-information solutions, are presented.

CONCLUSIONS

Orthopaedic leaders, armed with information and strategies, can help lead the way to solutions to the opioid epidemic in their respective communities, institutions, and subspecialty societies. Through leadership and education, orthopaedic surgeons can help shape the solution for this critical public health issue.

Rotator cuff rehabilitation: current theories and practice

A fully functioning, painless shoulder joint is essential to maintain a healthy, normal quality of life. Disease of the rotator cuff tendons (RCTs) is a common issue that affects the population, increasing with age, and can lead to significant disability and social and health costs. RCT injuries can affect younger, healthy patients and the elderly alike, and may be the result of trauma or occur as a result of chronic degeneration. They can be acutely painful, limited to certain activities or completely asymptomatic and incidental findings. A wide variety of treatment options exists ranging from conservative local and systemic pain modalities, to surgical fixation. Regardless of management ultimately chosen, physiotherapy of the RCT, rotator cuff muscles and surrounding shoulder girdle plays an essential role in proper treatment. Length of treatment, types of therapy and timing may vary if therapy is definitive care or part of a postoperative protocol. Allowing time for adequate RCT healing must always be considered when implementing ROM and strengthening after surgery. With current rehabilitation methods, patients with all spectrums of RCT pathology can improve their function, pain and quality of life. This manuscript reviews current theories and practice involving rehabilitation for RCT injuries.

Postoperative pain control after arthroscopic rotator cuff repair

Arthroscopic rotator cuff repair (ARCR) can provide excellent clinical results for patients who fail to respond to conservative management of symptomatic rotator cuff tears. ARCR, however, can be associated with severe postoperative pain and discomfort that requires adequate analgesia. As ARCR continues to shift toward being performed as an outpatient procedure, it is incumbent on physicians and ambulatory surgical centers to provide appropriate pain relief with minimal side effects to ensure rapid recovery and safe discharge. Although intravenous and oral opioids are the cornerstone of pain management after orthopedic procedures, they are associated with drowsiness, nausea, vomiting, and increased length of hospital stay. As health care reimbursements continue to become more intimately focused on quality, patient satisfaction, and minimizing of complications, the need for adequate pain control with minimal complications will continue to be a principal focus for providers and institutions alike. We present a review of alternative modalities for pain relief after ARCR, including cryotherapy, intralesional anesthesia, nerve blockade, indwelling continuous nerve block catheters, and multimodal anesthesia. In choosing among these modalities, physicians should consider patient- and system-based factors to allow the efficient delivery of analgesia that optimizes recovery and improves patient satisfaction.

Tendinopathy: Update on Pathophysiology

Synopsis Tendinopathy has become the accepted term to describe a spectrum of changes that occur in damaged and/or diseased tendons. Over the past 2 decades, there have been new insights into tendon pathophysiology of relevance to clinicians, including (1) better characterization of the overuse injury process and the resultant structural and functional disruption in chronically painful tendons, (2) improved understanding of the pathomechanics associated with chronic tendon injury, and (3) greater knowledge about the influence of lifestyle factors and drugs on tendon pathology. The implications of these new insights are discussed. J Orthop Sports Phys Ther 2015;45(11):833-841. Epub 21 Sep 2015. doi:10.2519/jospt.2015.5884.

Systemic EP4 Inhibition Increases Adhesion Formation in a Murine Model of Flexor Tendon Repair

Flexor tendon injuries are a common clinical problem, and repairs are frequently complicated by post-operative adhesions forming between the tendon and surrounding soft tissue. Prostaglandin E2 and the EP4 receptor have been implicated in this process following tendon injury; thus, we hypothesized that inhibiting EP4 after tendon injury would attenuate adhesion formation. A model of flexor tendon laceration and repair was utilized in C57BL/6J female mice to evaluate the effects of EP4 inhibition on adhesion formation and matrix deposition during flexor tendon repair. Systemic EP4 antagonist or vehicle control was given by intraperitoneal injection during the late proliferative phase of healing, and outcomes were analyzed for range of motion, biomechanics, histology, and genetic changes. Repairs treated with an EP4 antagonist demonstrated significant decreases in range of motion with increased resistance to gliding within the first three weeks after injury, suggesting greater adhesion formation. Histologic analysis of the repair site revealed a more robust granulation zone in the EP4 antagonist treated repairs, with early polarization for type III collagen by picrosirius red staining, findings consistent with functional outcomes. RT-PCR analysis demonstrated accelerated peaks in F4/80 and type III collagen (Col3a1) expression in the antagonist group, along with decreases in type I collagen (Col1a1). Mmp9 expression was significantly increased after discontinuing the antagonist, consistent with its role in mediating adhesion formation. Mmp2, which contributes to repair site remodeling, increases steadily between 10 and 28 days post-repair in the EP4 antagonist group, consistent with the increased matrix and granulation zones requiring remodeling in these repairs. These findings suggest that systemic EP4 antagonism leads to increased adhesion formation and matrix deposition during flexor tendon healing. Counter to our hypothesis that EP4 antagonism would improve the healing phenotype, these results highlight the complex role of EP4 signaling during tendon repair.

Stimulation of Rotator Cuff Repair by Sustained Release of Bone Morphogenetic Protein-7 Using a Gelatin Hydrogel Sheet

Bone morphogenetic protein-7 (BMP-7) promotes not only osteogenesis but also matrix production in chondrocytes and tenocytes. However, because of its short half-life, maintaining local concentrations of BMP-7 is difficult. We examined the use of a gelatin hydrogel sheet (GHS) for the sustained release of BMP-7 in stimulating rotator cuff repair at the tendon-to-bone insertion. Twelve-week-old male Sprague-Dawley rats were used. Radiolabeled BMP-7 ((125)I-BMP-7) was injected into the subacromial bursa in the (125)I-BMP-7 group, whereas a GHS impregnated with (125)I-BMP-7 was implanted on the tendon attached to the tendon-to-bone insertion in the (125)I-BMP-7+GHS group. Levels of (125)I-BMP-7 in the tendon-to-bone insertion were assessed at 1, 3, 7, 14, and 21 postoperative days. The BMP-7 concentrations were significantly higher in the (125)I-BMP-7+GHS group than in the (125)I-BMP-7 group. Next, the bilateral supraspinatus tendons were resected and sutured to the greater tuberosity of the humerus using the Mason-Allen technique. Treatment groups were created as follows: either phosphate-buffered saline (PBS) or BMP-7 was injected into the subacromial bursa in the PBS and BMP-7 groups, whereas a GHS impregnated with either PBS or BMP-7 was implanted on the repaired tendon attached to the tendon-to-bone insertion in the PBS+GHS and BMP-7+GHS groups. The resected specimens were stained at 2, 4, and 8 postoperative weeks with hematoxylin and eosin as well as Safranin O, and tissue repair was evaluated histologically by using the tendon-to-bone maturing score. Tissue repair was assessed biomechanically at 4 and 8 postoperative weeks. The BMP-7+GHS group at 8 postoperative weeks demonstrated a favorable cartilage matrix production and tendon orientation; moreover, the tendon-to-bone maturing score and the ultimate force-to-failure were the highest in this group. The ability of GHS to provide controlled release of various growth factors has been previously reported. We confirmed that the GHS releases BMP-7 in a sustained manner in the rat shoulder joint. At 8 postoperative weeks, the repaired tissue was mostly restored, both histologically and biomechanically, in the BMP-7+GHS group. We therefore conclude that the sustained release of BMP-7 from a GHS can stimulate rotator cuff repair.

Progress in cell-based therapies for tendon repair

The last decade has seen significant developments in cell therapies, based on permanently differentiated, reprogrammed or engineered stem cells, for tendon injuries and degenerative conditions. In vitro studies assess the influence of biophysical, biochemical and biological signals on tenogenic phenotype maintenance and/or differentiation towards tenogenic lineage. However, the ideal culture environment has yet to be identified due to the lack of standardised experimental setup and readout system. Bone marrow mesenchymal stem cells and tenocytes/dermal fibroblasts appear to be the cell populations of choice for clinical translation in equine and human patients respectively based on circumstantial, rather than on hard evidence. Collaborative, inter- and multi-disciplinary efforts are expected to provide clinically relevant and commercially viable cell-based therapies for tendon repair and regeneration in the years to come.