Nicotine delays tendon-to-bone healing in a rat shoulder model

Nicotine Dependence and Rates of Postoperative Complications in Achilles Tendon Repair

BACKGROUND

Nicotine is a modifiable risk factor that is well demonstrated to cause deleterious effects on tendon healing and overall health. Individuals that have a dependence on nicotine may be at an elevated risk for numerous postoperative complications when compared to nondependent patients. The purpose of this study is to evaluate the complications postoperatively between nicotine- and non-nicotine-dependent Achilles tendon repairs.

METHODS

The global health network database, TriNetX, was used to access and analyze deidentified patient information. Two cohorts were identified for the purposes of this study. Cohort A was defined as patients who had an Achilles tendon repair (Current Procedural Terminology [CPT]: 27650 or CPT: 27654) and had a dependence to nicotine (International Classification of Diseases, Tenth Revision, code: F17). Cohort B was defined as patients who had an Achilles tendon repair but did not have a dependence to nicotine. Data were gathered from health care organizations from August 21, 2000, to August 21, 2023. All postoperative complications were analyzed between 1 and 90 days after the Achilles tendon repair.

RESULTS

A total of 2117 nicotine-dependent patients were matched with 18 102 non-nicotine-dependent patients. After propensity matching for age at event, ethnicity, race, sex, and type 2 diabetes mellitus, nicotine-dependent patients who underwent Achilles tendon repair experienced higher associated risk for numerous postoperative complications. When compared to nondependent patients, nicotine-dependent patients had increased risk for wound disruption (risk ratio [RR] 1.55, 95% CI 1.11-2.16) and infection following a procedure (RR 1.64, 95% CI 1.09-2.47) within 90 days post Achilles tendon repair.

CONCLUSION

In this database study using propensity matching, nicotine-dependent patients who underwent Achilles tendon repair were correlated with an increased associated risk for wound disruption and infection after a procedure than their non-nicotine-dependent counterpart.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Combined therapy of platelet-rich plasma and basic fibroblast growth factor using gelatin-hydrogel sheet for rotator cuff healing in rat models

Introduction

Excellent outcomes of arthroscopic rotator cuff repair for small and medium tears have been recently reported. However, re-tears after surgery have been a common complication after surgical repair of large and massive rotator cuff tears and often occur in early postoperative phase. It was previously reported that basic fibroblast growth factor and platelet-rich plasma enhanced rotator cuff tear healing. We hypothesized that this combined therapy could enhance rotator cuff healing after rotator cuff repair in a rat model. This study aimed to evaluate the efficacy of combined therapy of platelet-rich plasma and basic fibroblast growth factor with gelatin-hydrogel sheet.

Methods

To create a rotator cuff defect, the infraspinatus tendon of Sprague Dawley rat was resected from the greater tuberosity. The infraspinatus tendons were repaired and covered with gelatin-hydrogel sheet impregnated with PBS (control group), basic fibroblast growth factor (bFGF group), platelet-rich plasma (PRP group), or both basic fibroblast growth factor and platelet-rich plasma (combined group). Histological examinations were conducted using hematoxylin and eosin, safranin O, and immunofluorescence staining, such as Isolectin B4, type II collagen at 2 weeks postoperatively. For mechanical analysis, ultimate failure load of the tendon-humeral head complex was evaluated at 6 weeks postoperatively.

Results

In the hematoxylin and eosin staining, the tendon maturing score of the combined group was higher than that of the control group at postoperative 2 weeks. In the safranin O staining, stronger proteoglycan staining was observed in the combined group compared with the other groups at postoperative 2 weeks. Vascular staining with isolectin B4 in 3 treatment groups was significantly higher than that in the control group. Type II collagen expression in the combined group was significantly higher than those in the other groups. The ultimate failure load of the combined group was significantly higher than that of the control group.

Conclusion

Combined therapy of basic fibroblast growth factor and platelet-rich plasma promoted angiogenesis, tendon maturing and fibrocartilage regeneration at the enthesis, which could enhance the mechanical strength. It was suggested that combined basic fibroblast growth factor and platelet-rich plasma might enhance both tendon and bone–tendon junction healing, and basic fibroblast growth factor and platelet-rich plasma might be synergistic.

Rotator cuff repair rehabilitation considerations and respective guidelines: a narrative review

Current rotator cuff repair rehabilitation protocols focus on multiple areas, including protecting the healing tissue, optimizing range of motion and strength, and returning the individual to labor demanding and sport-specific tasks. Post-operative rehabilitation timelines with consideration of the tear size remain variable among practitioners. Prognostic factors, healing rates, range of motion timeline, exercise progressions, and guidance on return to sport and work activity are the many factors that can help guide rotator cuff repair rehabilitation and ultimately may reduce failure rates and improve outcomes. The purpose of this narrative review is to outline the multi-factorial nature of rotator cuff pathology and guide treatment based on a multitude of factors.

Chronic Nicotine Exposure Minimally Affects Rat Supraspinatus Tendon Properties and Bone Microstructure

Cigarette smoking is the largest cause of preventable deaths, and a known risk factor for musculoskeletal issues including rotator cuff tendon tears. Tendon degeneration is believed to be due in part to changes in tendon cell health and collagen structure. Several studies have demonstrated that exposure to nicotine negatively impacts tendon healing, but surprisingly, nicotine exposure was shown to increase rat supraspinatus tendon stiffness. In order to address this seeming contradiction, the objective of this study was to comprehensively investigate the effects of long-term (18 weeks) exposure of nicotine on tendon-to-bone microstructural properties in a rat model. We hypothesized that long term subcutaneous nicotine delivery would lead to diminished tendon mechanical properties, decreased bone microstructure in the humeral head, and altered tendon cell morphology compared to age-matched control rats receiving saline. Results demonstrated a small decrease in tendon size and stiffness, with decreased cell density in the tendon midsubstance. However, no differences were found in the enthesis fibrocartilage or in the underlying subchondral or trabecular bone. In conclusion, our study revealed limited effects of nicotine on the homeostatic condition of the supraspinatus tendon, enthesis, and underlying bone. Future studies are needed to ascertain effects of other components of tobacco products.

Impact of smoking on patient-reported outcome measures after arthroscopic rotator cuff repair: a 2-year comparative cohort study

Background and Hypothesis

Smoking is a well-established risk factor for tendon healing. The purpose of this study was to evaluate the differences in patient-reported outcome measures between smokers and nonsmokers who have undergone arthroscopic rotator cuff repair. It was hypothesized that smokers would have worse self-reported outcomes at 1 and 2 years postoperatively.

Methods

A total of 560 consecutive patients who underwent arthroscopic rotator cuff repair were divided into 2 groups: group I (smokers) n = 25 and group II (nonsmokers) n = 535. All participants were administered preoperative and postoperative surveys consisting of the following outcome-measuring tools: (i) visual analog scale, (ii) Veterans Rand 12-Item Health Survey, (iii) American Shoulder and Elbow Surgeons shoulder score, (iv) standard preoperative form consisting of 4 questions regarding their expectations of recovery, (v) Single Assessment Numeric Evaluation shoulder score, and (vi) Simple Shoulder Test.

Results

At 1 and 2 years postoperative, nonsmokers reported statistically significant differences in Veterans Rand 12-Item Health Survey mental scores (56.2 vs. 51.9, P = .0162 and 56.3 vs. 49.5, P = .0004, respectively). American Shoulder and Elbow Surgeons Shoulder scores showed no differences until the 2-year mark, at which time nonsmokers reported higher scores than smokers (87.9 vs. 79.0, P = .0212). Single Assessment Numeric Evaluation scores also remained similar up until 2-year follow-up, at which time nonsmokers reported statistically significant improvement (80.0 vs. 68.5, P = .0339). Nonsmokers reported higher Simple Shoulder Test scores at baseline and at 2-year follow-up (43.3 vs. 37.0, P = .0417 and 83.7 vs. 68.1, P = .0046, respectively).

Conclusion

At 2 years postoperatively, nonsmokers had significantly higher patient-reported outcome measure scores than smokers. In elective surgery, smoking status should be considered as a risk factor for poorer patient-reported outcomes after arthroscopic rotator cuff repair. However, smokers continue to report a clinical benefit at 2 years postoperatively.

Ascorbic acid mitigates the deleterious effects of nicotine on tendon stem cells

Purpose: Nicotine causes tendon degeneration, whereas ascorbic acid imparts beneficial effects on tendon cells. Tendon stem cells (TSCs) play a vital role in maintaining tissue integrity and promoting restoration of structure and function after tendon injury. In the present study, cell culture experiments were performed to determine the effects of nicotine on TSCs and whether ascorbic acid supplementation could antagonize the action of high concentration nicotine. Methods: After treatment with nicotine and ascorbic acid, TSC proliferation, migration, stemness, apoptosis, and differentiation were analyzed. Results: TSC proliferation and expression of stem cell markers were significantly impaired by a high concentration of nicotine (1000 ng/mL), but a lower concentration (100 ng/mL) induced proliferative effects in TSCs. Moreover, the highest concentration of nicotine tested (1000 ng/mL) significantly inhibited the migratory ability of TSCs, while relatively high concentrations (100 and 1000 ng/mL) significantly (p < 0.05) up-regulated non-tenocyte genes. When ascorbic acid was added, the inhibitory effects of nicotine on the proliferation, migration, and stemness of TSCs were reversed. In addition, flow cytometry analysis showed that these nicotine concentrations could induce cell apoptosis, while the addition of ascorbic acid inhibited apoptosis. Conclusion: Addition of ascorbic acid partially reversed the inhibitory effect of a high concentration of nicotine. These findings indicate that while nicotine impairs the biological characteristics of TSCs, ascorbic acid can mitigate these deleterious effects and, therefore, may be useful for decreasing nicotine-induced tendon degeneration.

Smoking as a risk factor for complications following arthroscopic rotator cuff repair

Background

The purpose of this study was to investigate the association between smoking status and postoperative complications within 30 days of arthroscopic rotator cuff repair (ARCR).

Methods

The American College of Surgeons National Surgical Quality Improvement Program database was queried to identify all patients who underwent ARCR from 2015 to 2017. Smokers were defined as patients who reported smoking cigarettes in the year prior to rotator cuff repair. Patients who used chewing tobacco, cigars, or electronic cigarettes were not included in the smoking cohort. Postoperative complications were reported within 30 days of the procedure. Multivariate logistic regression was performed to investigate the relationship between smoking status and postoperative complications.

Results

There were 18,594 patients included in this study. Of these patients, 2834 (15.2%) were current smokers. Smokers were more likely to be men, to be aged < 65 years, and to have a body mass index < 30. Smokers were also more likely to have chronic obstructive pulmonary disease, to be functionally dependent, and to have an American Society of Anesthesiologists (ASA) class ≥ 3. After adjustment for all significantly associated patient demographic characteristics and comorbidities, smoking was identified as a significant predictor of surgical complications (odds ratio [OR], 1.955; P = .022), return to the operating room (OR, 2.547; P = .003), readmission (OR, 1.570; P = .014), and sepsis or septic shock (OR, 4.737; P = .021). Smoking was not a significant predictor of medical complications (OR, 1.105; P = .687) or surgical-site infections (OR, 1.216; P = .713).

Conclusion

Smoking may be a risk factor for surgical complications, readmission, and sepsis or septic shock within 30 days of ARCR.

Effect of Smoking on Postoperative Function and Quality of Life After Full Thickness Arthroscopic Rotator Cuff Repair: A Retrospective Analysis

PURPOSE

The effect of smoking on preoperative and postoperative outcome scores as well as quality of life measurements after arthroscopic rotator cuff repair (ARCR) has not been fully understood, and studies regarding this are lacking in the literature. This study aimed to evaluate the effect of smoking on function and quality of life after ARCR.

METHODS

Two-hundred patients who underwent full-thickness ARCR with a minimum 1-year follow-up period were included and evaluated retrospectively. The patients were divided into two groups: smokers (Group 1, 59 patients) and nonsmokers (Group 2, 141 patients). Pre- and postoperative Constant Murley (CM) scores, American Shoulder and Elbow Surgeons (ASES) scores, visual analogue scale scores (VASs), and Short-Form 36 health survey (SF-36) scores were used to evaluate functional and quality of life outcomes. The correlation between the smoking amount (pack-years) and outcomes was evaluated.

RESULTS

A total of 200 patients included into study (90 male and 110 female) with mean age of 62.68 ± 3.98. There was no statistically significant difference between the two groups regarding preoperative scores, except in the ASES score (P = 0.021 ) Additionally, there was a statistically significant difference between the groups regarding postoperative CM score, ASES score, and VAS, and in physical functioning and role limitations due to physical health domains of the SF-36 (P = 0.029, P = 0.038, P = 0.021 and P = 0.020, respectively). There were small to moderate negative correlations between amount of smoking and preoperative physical functioning, role limitations from emotional problems, energy/fatigue, emotional well-being, and pain domains of the SF-36. However, there were moderate to strong negative correlations between amount of smoking and postoperative SF-36 domains.

CONCLUSION

Preoperative and postoperative functional outcome scores, and quality of life measurements are negatively affected from smoking. As the amount of smoking increases, postoperative results are negatively affected.

LEVEL OF EVIDENCE

3.

Regeneration of a full-thickness defect in rotator cuff tendon with umbilical cord-derived mesenchymal stem cells in a rat model

Although rotator cuff disease is a common cause of shoulder pain, there is still no treatment method that could halt or reveres its development and progression. The purpose of this study was to investigate the efficacy of umbilical cord-derived mesenchymal stem cells (UC MSCs) on the regeneration of a full-thickness rotator cuff defect (FTD) in a rat model. We injected either UC MSCs or saline to the FTD and investigated macroscopic, histological and biomechanical results and cell trafficking. Treatment with UC MSCs improved macroscopic appearance in terms of tendon thickness at two weeks, and inflammation, defect size, swelling/redness and connection surrounding tissue and slidability at four weeks compared to the saline group. Histologically, UC MSCs induced the tendon matrix formation recovering collagen organization, nuclear aspect ratio and orientation angle of fibroblast as well as suppressing cartilage-related glycosaminoglycan compared to saline group at four weeks. The UC MSCs group also improved ultimate failure load by 25.0% and 19.0% and ultimate stress by 27.3% and 26.8% at two and four weeks compared to saline group. UC MSCs labeled with PKH26 exhibited 5.3% survival at four weeks compared to three hours after injection. This study demonstrated that UC MSCs regenerated the FTD with tendon tissue similar properties to the normal tendon in terms of macroscopic, histological and biomechanical characteristics in a rat model.

Regeneration of a full-thickness defect of rotator cuff tendon with freshly thawed umbilical cord-derived mesenchymal stem cells in a rat model

BACKGROUND

It is difficult to immediately use mesenchymal stem cells (MSCs) for the patient with rotator cuff disease because isolation and culture time are required. Thus, the MSCs would be prepared in advanced in cryopreserved condition for an "off-the-shelf" usage in clinic. This study investigated the efficacy of freshly thawed MSCs on the regeneration of a full-thickness tendon defect (FTD) of rotator cuff tendon in a rat model.

METHODS

We evaluated morphology, viability, and proliferation of cultured umbilical cord-derived MSCs (C-UC MSCs) and freshly thawed umbilical cord-derived MSCs (T-UC MSCs) at passage 10 in vitro. In animal experiments, we created a FTD in the supraspinatus of rats and injected the injured tendon with saline, cryopreserved agent (CPA; control), C-UC MSCs, and T-UC MSCs, respectively. Two and 4 weeks later, macroscopic, histological, biomechanical, and cell trafficking were evaluated. T test and ANOVA were used with SPSS. Differences with p < .05 were considered statistically significant.

RESULTS

T-UC MSCs had fibroblast-like morphology and showed greater than 97% viability and stable proliferation comparable to the C-UC MSCs at passage 10. In animal experiments, compared with the control group, the macroscopic appearance of the T-UC MSCs was more recovered at 2 and 4 weeks such as inflammation, defect size, neighboring tendon, swelling/redness, the connecting surrounding tissue and slidability. Histologically, the nuclear aspect ratio, orientation angle of fibroblasts, collagen organization, and fiber coherence were improved by 33.33%, 42.75%, 1.86-fold, and 1.99-fold at 4 weeks, and GAG-rich area decreased by 88.13% and 94.70% at 2 and 4 weeks respectively. Further, the T-UC MSCs showed enhanced ultimate failure load by 1.55- and 1.25-fold compared with the control group at both 2 and 4 weeks. All the improved values of T-UC MSCs were comparable to those of C-UC MSCs. Moreover, T-UC MSCs remained 8.77% at 4 weeks after injury, and there was no significant difference between C-UC MSCs and T-UC MSCs.

CONCLUSIONS

The morphology, viability, and proliferation of T-UC MSCs were comparable to those of C-UC MSCs. Treatment with T-UC MSCs could induce tendon regeneration of FTD at the macroscopic, histological, and biomechanical levels comparable to treatment with C-UC MSCs.

Rotator cuff tear degeneration and the role of fibro-adipogenic progenitors

The high prevalence of rotator cuff tears poses challenges to individual patients and the healthcare system at large. This orthopedic injury is complicated further by high rates of retear after surgical repair. Outcomes following repair are highly dependent upon the quality of the injured rotator cuff muscles, and it is, therefore, crucial that the pathophysiology of rotator cuff degeneration continues to be explored. Fibro-adipogenic progenitors, a major population of resident muscle stem cells, have emerged as the main source of intramuscular fibrosis and fatty infiltration, both of which are key features of rotator cuff muscle degeneration. Improvements to rotator cuff repair outcomes will likely require addressing the muscle pathology produced by these cells. The aim of this review is to summarize the current rotator cuff degeneration assessment tools, the effects of poor muscle quality on patient outcomes, the role of fibro-adipogenic progenitors in mediating muscle pathology, and how these cells could be leveraged for potential therapeutics to augment current rotator cuff surgical and rehabilitative strategies.

Synovial Fluid Volume at the Time of Arthroscopic Rotator Cuff Repair Correlates With Tear Size

Background

Inflammatory biomarkers are increased in the synovium and tendon of rotator cuff tears. Several studies demonstrate an associated increase in these markers and size of the tear, with implications of chondral destruction leading to rotator cuff tear arthropathy and glenohumeral arthritis.

Methods

This is a prospective study of 105 patients undergoing arthroscopic rotator cuff repair in which intra-articular synovial fluid was aspirated just prior to arthroscopy. Adult patients with a partial or full-thickness rotator cuff tear undergoing arthroscopic repair were included, and those with inflammatory arthritis, active infection, open cuff repair, intraoperative findings of osteoarthritis, or those undergoing revision cuff repair were excluded.

Results

The average patient age was 58 years (range 33-74 years), with 59 (56.2%) males. The mean aspirate volume of partial tears was 0.76 ± 0.43 mL, small tears 1.46 ± 1.88 mL, medium tears 3.04 ± 2.21 mL, and large tears 6.60 ± 3.23 mL. Full-thickness versus partial tears had significantly more synovial fluid (3.64 vs. 0.76 mL, respectively, p < 0.0001). An aspiration volume of 1.5 mL or greater resulted in 91.3% specificity and 96.8% positive predictive value for a full-thickness tear. Smoking (p = 0.017), tear size (p < 0.0001), and tears of the infraspinatus (p = 0.048) were significantly correlated with synovial fluid volume. Age, body mass index, chronicity of tear, sex, subscapularis involvement, supraspinatus involvement, and teres minor involvement had no association to synovial fluid volume.

Conclusion

Preoperative aspiration of the glenohumeral joint to identify the volume of synovial fluid can aid to identify full-thickness rotator cuff tears, and increased fluid volume should alert the clinician of a large tear.

Risk factors for surgery due to rotator cuff disease in a population-based cohort

AIMS

Few risk factors for rotator cuff disease (RCD) and corresponding treatment have been firmly established. The aim of this study was to evaluate the relationship between numerous risk factors and the incidence of surgery for RCD in a large cohort.

METHODS

A population-based cohort of people aged between 40 and 69 years in the UK (the UK Biobank) was studied. People who underwent surgery for RCD were identified through a link with NHS inpatient records covering a mean of eight years after enrolment. Multivariate Cox proportional hazards regression was used to calculate hazard ratios (HRs) as estimates of associations with surgery for RCD accounting for confounders. The risk factors which were considered included age, sex, race, education, Townsend deprivation index, body mass index (BMI), occupational demands, and exposure to smoking.

RESULTS

Of the 421,894 people who were included, 47% were male. The mean age at the time of enrolment was 56 years (40 to 69). A total of 2,156 people were identified who underwent surgery for RCD. Each decade increase in age was associated with a 55% increase in the incidence of RCD surgery (95% confidence interval (CI) 46% to 64%). Male sex, non-white race, lower deprivation score, and higher BMI were significantly associated with a higher risk of surgery for RCD (all p < 0.050). Greater occupational physical demands were significantly associated with higher rates of RCD surgery (HR = 2.1, 1.8, and 1.4 for 'always', 'usually', and 'sometimes' doing heavy manual labour vs 'never', all p < 0.001). Former smokers had significantly higher rates of RCD surgery than those who had never smoked (HR 1.23 (95% CI 1.12 to 1.35), p < 0.001), while current smokers had similar rates to those who had never smoked (HR 0.94 (95% CI 0.80 to 1.11)). Among those who had never smoked, the risk of surgery was higher among those with more than one household member who smoked (HR 1.78 (95% CI 1.08 to 2.92)). The risk of RCD surgery was not significantly related to other measurements of secondhand smoking.

CONCLUSION

Many factors were independently associated with surgery for RCD, including older age, male sex, higher BMI, lower deprivation score, and higher occupational physical demands. Several of the risk factors which were identified are modifiable, suggesting that the healthcare burden of RCD might be reduced through the pursuit of public health goals, such as reducing obesity and modifying occupational demands. Cite this article: Bone Joint J 2020;102-B(3):352-359.

Retears of the Rotator Cuff: An Ultrasonographic Assessment During the First Postoperative Year

Background

Surgical repair of rotator cuff (RC) tears is an effective treatment option. However, the prevalence of recurrent ruptures is high.

Hypothesis

Recurrent tears are a frequent complication of surgical repair of RC tears. Their incidence might be influenced by factors such as the patient's age and size of the initial tear.

Study Design

Case series; Level of evidence, 4.

Methods

Data from 90 adult patients who underwent arthroscopic RC repair between 2014 and 2017 and underwent an ultrasound examination 6 to 12 months after surgery were analyzed retrospectively. Massive tears were repaired using a double-row technique, and nonmassive tears were repaired with a single-row technique. Clinical records were reviewed for demographic information.

Results

All patients (57.8% women; 42.2% men) were older than 18 years (mean, 58.9 years). Of these patients, 30.0% (27/90) had massive tears, which were primarily found in patients ≥60 years (74.1%; 20/27). Complete healing was seen in 74.5% of all repairs during follow-up. A total of 23 patients (25.5%) had retears (13 complete; 10 partial), which were diagnosed by ultrasound imaging 6 to 12 months after the initial surgery. The occurrence of retears was more prevalent in patients with massive tears than in patients with nonmassive tears (40.7% vs 19.0%, respectively); the difference was statistically significant (P = .03). Reruptures occurred in 50.0% of patients older than 60 years with massive tears. Although patients older than 60 years had more recurrent tears (32.6%) compared with younger patients (18.2%), the difference was not statistically significant (P = .12).

Conclusion

One-quarter of the patients who had undergone surgical repair of an RC tear had recurrent ruptures. There was a statistically significant association between the initial massive tear and a retear. Patients older than 60 years showed a higher recurrence rate, but this difference lacked statistical significance. Reruptures occurred in 50.0% of patients older than 60 years with massive tears.

Unplanned Reoperation After Surgery for Scapholunate Interosseous Ligament Insufficiency: A Retrospective Review of 316 Patients

Background: The purpose of this study was to identify factors associated with unplanned reoperation after surgery for scapholunate interosseous ligament (SLIL) insufficiency. Methods: Using Current Procedural Terminology (CPT) codes from 3 hand surgery centers across 2 metropolitan areas, we identified 316 patients undergoing surgery for SLIL insufficiency from 2000 to 2014. Medical records were manually reviewed to collect data on factors that might be associated with unplanned reoperation, including age, sex, tobacco use, occupation, acuity of treatment, and reconstruction method. Results: Thirty-eight patients (12%) had an unplanned reoperation; most of them (65%) were a secondary reconstruction or salvage procedure (eg, 6 proximal row carpectomies, 9 revision reconstruction, and 10 partial carpal arthrodeses), while 5 (13%) were for unplanned screw removal. The median time between the index and second surgery was 16 months (range, 2-97 months). The type of index procedure was not associated with reoperation. The only factor associated with reoperation was cigarette smoking, and this association persisted when looking specifically at reoperations for revision or salvage. Conclusions: Patients should be counseled that smoking is associated with reoperation after SLIL surgery. Smoking cessation or decreasing nicotine usage may be beneficial prior to surgery. With the numbers available, there was no association between surgical technique and reoperation.

Partial thickness rotator cuff tears: Patient demographics and surgical trends within a large insurance database

Introduction

Partial thickness rotator cuff tears (PTRCT) are a common injury reported in 13-32% of the population, yet most of the current literature focuses on full thickness rotator cuff tears. Therefore, the purpose of this study was to analyze trends among patients with PTRCT including: (1) demographics; (2) comorbidities; (3) cost of care; (4) setting of initial diagnosis; and (5) change in incidence of PTRCT or surgical approach over time.

Methods

A Medicare patient-population consisting of 44 million lives was retrospectively analyzed from 2007 to 2017 using International Classification of Disease, 9th Revision (ICD-9) codes. Patients were identified for PTRCT using ICD-9 code: 726.13. The query yielded a total of 44,978 patients all of which had been previously diagnosed with PTRCT. Primary trends analyzed included: demographics, comorbidities, cost of care, initial setting of diagnosis, and change in incidence of PTRCT or surgical approach over time.

Results

PTRCTs and surgical repair of PTRCTs were most common in patients ages 65 to 69 and least common in patients who were 85 and older. Incidence of PTRCT was greater in females (54.12%) than males (45.88%). Comorbidities found within the population included hypertension, hyperlipidemia, diabetes mellitus, tobacco use, obesity, rheumatoid arthritis, and osteoarthritis of the shoulder. The average cost per episode of care totaled $9,923.26. PTRCTs were most commonly diagnosed in patients who resided in assisted living facilities (n = 27,106), making up 60% of the patient population. Reported incidence of PTRCT has increased substantially along with the surgical repair of PTRCT.

Conclusion

Reported cases of PTRCT and its surgical repair have both increased substantially over time. Approximately 11.70% of patients with PTRCT undergo either open or arthroscopic procedure as a means of surgical repair. With the growing popularity of arthroscopic procedures for rotator cuff repair, further investigation should be performed to analyze trends and risk factors for PTRCT, a seemingly underrepresented orthopedic condition.

Evaluating strategies and outcomes following rotator cuff tears

INTRODUCTION

Rotator cuff tear surgical repair techniques have significantly progressed. However, tendon retear following primary repair persistently occurs at high rates. Rehabilitation protocols, surgical fixation techniques, biologic therapy with scaffolds, platelet-rich plasma, and even stem cell applications are under study to promote adequate tendon healing.

METHODS

A nonsystematic query of the PubMed database was conducted in July 2016 utilizing the search terms "rotator cuff repair," "tear," "rehabilitation," "scaffold," "platelet-rich plasma," and "stem cell" to identify, analyze, and summarize relevant studies.

CONCLUSION

Individualized rehabilitation protocols may be the best approach for small to medium sized tears. Surgical fixation will continue to be debated as modifications to single-row technique and increases in suture number have improved tensile strength. Double-row repairs have been associated with higher costs. Transosseous equivalent technique exhibits comparable subjective and objective outcomes to single- and double-row repair at two-year follow-up. Biocompatible scaffold augmentation has showed inconsistent short-term results. Platelet-rich plasma has lacked uniformity in treatment preparation, administration, and outcome measurement with mixed results. Few human studies have suggested decreased retear rates and improved repair maintenance following bone marrow-derived mesenchymal stem cell augmentation. This review reiterated the necessity of additional high-quality, large-sample studies to develop any final verdict regarding efficacy.

Chronic Nicotine Exposure Alters Uninjured Tendon Vascularity and Viscoelasticity

Background:

Although nicotine and tobacco use are well established to have adverse health effects, the effects on tendons are less well understood. The purpose of this study was to investigate the effect of chronic nicotine exposure on Achilles tendon (AT) and supraspinatus tendon (SS) physiologic and mechanical properties in a rodent model.

Methods:

Sprague-Dawley rats (n = 20) were exposed to either 0.9% saline or 36 mg/mL nicotine through an implantable osmotic pump for 12 weeks. At 12 weeks, the AT was imaged in vivo with contrast-enhanced ultrasound (CE-US) to assess vascularity. Bilateral AT and SS were then harvested for ex vivo biomechanical analysis. Statistical analysis was performed using Student t test and Mann Whitney U test.

Results:

AT CE-US demonstrated a significantly increased wash-in rate in the nicotine group compared to the saline group, indicating an increase in tissue perfusion rate in the nicotine group. AT percent stress relaxation, a measure of tendon viscoelasticity, was significantly increased in the nicotine group compared to the saline group. Similarly, there was a trend toward increased SS percent stress relaxation in the nicotine group compared to the saline group. No differences in other mechanical properties were observed.

Conclusion:

AT perfusion rate increased and both AT and SS viscoelasticity were altered with chronic nicotine exposure at a clinically relevant dose that models the average smoker in the United States (14 cigarettes per day). Further studies are necessary to link these properties with tendon degeneration and injury.

Clinical Relevance:

Chronic nicotine exposure affects tendon health. Patients should be counseled as such.

Negative Predictors of Outcomes of Flexor Tendon Repairs

The current trend in hand surgery has streamlined the treatment of acute hand trauma to the modern-day surgery unit. As the volume of hand trauma caseloads continues to increase, it is becoming increasingly difficult to schedule patients for theater on the day of injury. It, therefore, becomes paramount to adequately triage patients in accordance with best clinical evidence and predictors of poor clinical outcomes.

Animal models suggest that the earlier flexor tendons are repaired, the better the patient functional outcome. The largest study to date examining the timing of injury to functional post-operative outcome also recognizes that the faster these injuries are repaired, the better the patient outcome. Age-related changes to tendon biomechanics and structure are well-documented. However, no conclusive evidence exists specific to the degenerative changes and mechanical properties of flexor tendons in humans. The animal model strongly suggests that increasing age is associated with local architectural and biological changes that directly affect the tendon repair functional outcome. Although retrospective analyses to date suggest that smoking is a negative outcome predictor for functional tendon outcome, no prospective large-scale studies exist.

A large, single-center prospective study specifically examining the positive and negative outcome predictors of flexor tendon repairs and functional post-operative outcome is warranted. The negative predictive model of patient care may enable us to further council patients preoperatively and stratify patients according to clinical need.

Nicotine impairs intra-substance tendon healing after full thickness injury in a rat model

Nicotine is harmful to many bodily systems; however, the effects of nicotine on intra-substance tendon healing remain largely unexplored. The purpose of this study was to examine the functional, structural, and biomechanical effects of nicotine on the healing of Achilles tendons in rats after an acute full-thickness injury. Sixty Sprague-Dawley rats were enrolled in this study. Half were exposed to 0.9% saline and half to 61 ng/mL of nicotine for 3 months via subcutaneous osmotic pumps. At 3 months, all rats underwent blunt full thickness transection of the left Achilles tendon and were immobilized for one week in plantarflexion. In-vivo assays were conducted prior to injury, at 21 days, and at 42 days post-injury and included the following: Functional limb assessment, passive joint mechanics, and vascular evaluation. Rats were sacrificed at 21 and 42 days for biomechanical testing and histologic evaluation. Rats exposed to nicotine demonstrated decreased vascularity, greater alteration in gait mechanics, and increased passive ROM of the ankle joint. Biomechanically, the nicotine tendons failed at lower maximum loads, were less stiff, had smaller cross-sectional areas and had altered viscoelastic properties. Histologically, nicotine tendons demonstrated decreased vessel density at the injury site. This study demonstrates that nicotine leads to worse functional outcomes and biomechanical properties in tendons. The decreased vascularity in the nicotine group may suggest an underlying mechanism for inferior tendon healing. Patients should be counseled that using nicotine products increase their risk of poor tendon healing and may predispose them to tendon re-rupture. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.

Early versus delayed mobilization following rotator cuff repair

Rotator cuff tears are a common cause for pain and reduced function. Tears of the tendons of the cuff can be a result of a degenerative process or as a consequence of trauma. Management of cuff tears are surrounded by controversy from indications for surgical management to rehabilitation protocol post-surgical repair. The aim of post surgical rehabilitation is to improve functional outcome, reduce pain and promote tendon healing. In the case of rotator cuff repair, rehabilitation can be broadly divided into early passive range of motion (EPM) and delayed range of motion (DRM). The EPM regime is defined by minimal immobilisation of the shoulder and passive mobilisation of the joint within the first post-operative period. In contrast, DRM immobilises the shoulder joint up to six weeks post-operatively. Proponents of EPM state various advantages of their rehabilitation protocol including improved range of motion and earlier return to normal activities of daily living. However, there has also been concern that this rehabilitation regime may result in an increased rate of re-rupture. Since this is a highly controversial issue, various high quality literature have been published looking to clarify which regime is best following rotator cuff surgery. Reviewing these articles, it appears that there is an increase rate of re-tear of the repaired rotator cuff tendon when the EPM regime is employed. Statistical significance however was limited by small sample sizes. Range of motion post-repair also appears to be associated with post-operative rehabilitation regime. As expected, the EPM regime has been shown to improve range of motion post-repair. Despite this, literature reports patients managed with the DPM showed a statistically better patient reported outcome measure. We conclude that based on the evidence we currently have, early range of motion post rotator cuff repair is related with an increase risk of re-tear. The DPM regime reduces this risk with the possible complication of reduced range of shoulder movement. This problem is thought to be an easier clinical issue to deal with compared to re-rupture of the repaired rotator cuff tendon. There is however lack of data to achieve statistical significance in most of these analysis. There is a definite need for a large, multi-centre single blinded randomised controlled trial to further shed light on this controversial topic.

Impact of smoking on patient outcomes after arthroscopic rotator cuff repair

Background

Cigarette smoking may adversely affect rotator cuff tear pathogenesis and healing. However, the impact of cigarette smoking on outcomes after arthroscopic rotator cuff repair is relatively unknown.

Patients and methods

A cohort of 126 patients who underwent arthroscopic rotator cuff repair with minimum 2 years follow-up were retrospectively identified from our institutional database. Patient demographics, comorbidities, and cuff tear index were collected at initial presentation. Outcome measures including American Shoulder and Elbow Surgeons (ASES) score, Western Ontario Rotator Cuff (WORC) score and Visual Analogue Scale (VAS) for pain were collected at each clinical follow-up. Mixed model regression analysis was used to determine the impact of smoking on outcomes, while controlling for tear size and demographics.

Results

In our cohort, 14% were active or recent smokers. At baseline, smokers presented with higher pain, greater comorbidities and worse ASES scores than non-smokers. Smokers also had a non-significant trend towards presenting for surgical repair at a younger age and with larger tear sizes. Both smokers and non-smokers had statistical improvements in outcomes at 2 years following repair. Regression analysis revealed that smokers had a worse improvement in ASES but not WORC or VAS pain scores after surgery.

Conclusion

The minimal clinically important difference was achieved for ASES, WORC and VAS pain in both smokers and non-smokers, suggesting both groups substantially benefit from arthroscopic rotator cuff repair. Smokers tend to present with larger tears and worse initial outcome scores, and they have a lower functional improvement in response to surgery.

Comorbidity effect on speed of recovery after arthroscopic rotator cuff repair

Background

Comorbidities have been shown to affect rotator cuff healing and postoperative outcomes. The purpose of this study was to analyze the effect of comorbidities on speed of recovery (SOR) and overall outcomes after arthroscopic rotator cuff repair (RCR).

Methods

We identified 627 patients who underwent primary arthroscopic RCR from 2006 to 2015. Measured motion and patient-reported outcome measures for pain and function were analyzed for preoperative, 3-month, 6-month, and 1-year intervals. Subgroup analysis of overall outcome and plateau in maximum improvement was performed for diabetes, smoking, obesity, hypercholesterolemia, and age.

Results

Diabetic patients had worse pain (visual analog scale for pain) and functional outcome (American Shoulder and Elbow Surgeons function, Simple Shoulder Test, visual analog scale for function, and elevation) scores at 6 months and 1 year (P < .05), with an earlier plateau in recovery (6 months) for nearly all variables. Smoking had no impact on postoperative outcome scores; however, plateaus occurred earlier in smokers (6 months). Obese patients had worse American Shoulder and Elbow Surgeons function score and external rotation at 1 year (P < .05) with similar plateau points. No significant differences were observed in outcomes for patients with hypercholesterolemia; however, plateaus for Single Assessment Numeric Evaluation and motion occurred earlier (6 months). Outcome scores for patients older than 65 years were not significantly different from those for younger patients.

Conclusion

After arthroscopic RCR, SOR for pain outpaced that for function and motion. Diabetic patients had worse outcomes and earlier plateau points. Earlier plateaus were seen for smokers and for motion in patients with obesity or hypercholesterolemia. Obese patients showed lower functional scores and external rotation. Age did not significantly influence SOR.

Targeting Inflammation in Rotator Cuff Tendon Degeneration and Repair

Rotator cuff degeneration is a common affliction that results in pain and disability. Tendinopathy was historically classified with or without the involvement of the immune system. However, technological advancements in screening have shown that the immune system is both present and active in all forms of tendinopathy. During injury and healing, the coordinated effort of numerous immune cell populations work with the resident stromal cells to break down damaged tissues and stimulate remodeling. These cells deploy a wide array of tools, including phagocytosis, enzyme secretion, and chemotactic gradients to direct these processes. Yet, there remains a knowledge gap in our understanding of the sequence of critical events and regulatory factors that mediate this is process in injury and healing. Furthermore, current treatments do not specifically target inflammation at the molecular level. Typical regimens include non-steroidal anti-inflammatory drugs or corticosteroids; however, researchers have found irrevocable functional deficits following treatment, and have disputed their long-term efficacy. Therefore, developing therapeutics that specifically consider the nuances of the immune system are necessary to improve patient outcomes.

What is the role of systemic conditions and options for manipulation of bone formation and bone resorption in rotator cuff tendon healing and repair?

Rotator cuff pathology is a significant cause of shoulder pain. Operative repair of rotator cuff is an established standard of care for these patient, however, failure of the procedure is common. Systemic conditions such as diabetes mellitus, hypocholesteremia, thyroid disease, and smoking significantly affect the outcomes of rotator cuff repair and have significant implications for the management of these patients. Diabetes mellitus has been proposed to damage tendons through non-enzymatic glycosylation of collagen with advanced glycation end product formation and impaired microcirculation. Hypocholesteremia may lead to fatty infiltration and subsequent pro-inflammatory degenerative enzymatic degeneration. Thyroid disease may disrupt tendon homeostasis through the alteration of collagen production and the accumulation of glycosaminoglycans. Lastly, smoking inhibits tendon healing through the induction of hypovascularity and hypoperfusion. Understanding of the implications these systemic conditions have on the outcomes is important in the management of rotator cuff disease.

Greater Sensitivity of Oral Fibroblasts to Smoked Versus Smokeless Tobacco

BACKGROUND

Smokers have an increased incidence and severity of periodontal disease. Although cigarette smoke contains >4,000 chemical components that could affect periodontal tissues, less is understood about the effect of smokeless tobacco. Therefore, this study compares the effects of cigarette smoke extract (CSE) and smokeless tobacco extract (STE) on cell survival and motility of periodontal ligament (PDL) and gingival fibroblasts in vitro.

METHODS

PDL and gingival fibroblasts were exposed to various concentrations of CSE, STE, or nicotine alone. Viable cells were labeled with calcein acetoxymethyl, visualized using fluorescent microscopy, and quantified using a fluorescence multi-well plate reader. In vitro wounding and collagen gel contraction assays were used to assess cell motility.

RESULTS

Both gingival and PDL fibroblasts displayed reduced cell viability with increasing concentrations of CSE and STE. Based on relative nicotine content, CSE was significantly more cytotoxic than STE. PDL fibroblasts were also more sensitive to both CSE and STE compared with gingival fibroblasts. Finally, sublethal doses of CSE reduced cell motility and gel contraction, whereas STE had less effect. Nicotine alone ≤0.5 mM had little to no effect in any of these assays.

CONCLUSIONS

Many of the underlying effects of tobacco products on periodontal tissues may be due to direct inhibition of normal fibroblast function. CSE is found to be more deleterious to the function of both PDL and gingival fibroblasts than STE. PDL fibroblasts appear to be more sensitive to CSE and STE than gingival fibroblasts. Therefore, cigarette smoke may have more profound effects than smokeless tobacco.

Prognosis Driven Rehabilitation After Rotator Cuff Repair Surgery

Background:

Rehabilitation after rotator cuff repair surgery has been the focus of several clinical trials in the past decade. Many illuminate new evidence with regard to the prognosis of structural and functional success after surgery.

Methods:

A selective literature search was performed and personal physiotherapeutic and surgical experiences are reported.

Results:

Post-operative rehabilitation parameters, namely the decision to delay or allow early range of motion after surgery, play a large role in the overall success after surgery. Using a prognosis driven rehabilitation program offers clinicians a means of prescribing optimal rehabilitation parameters while ensuring structural and functional success. This commentary aims to synthesize the evidence in a spectrum of prognostic factors to guide post-operative rehabilitation.

Conclusion:

The optimal rehabilitation program after rotator cuff repair surgery is debatable; therefore, we suggest using a spectrum of prognostic factors to determine a rehabilitation program suited to ensure structural and functional success, quickly and safely.

Immunobiological factors aggravating the fatty infiltration on tendons and muscles in rotator cuff lesions

Rotator cuff lesions (RCLs) are a common cause of shoulder pain and dysfunction. The rotator cuff tendons can degenerate and/or tear from the greater tuberosity of the humerus, which is associated with several anatomical, physiological, biochemical, and molecular changes in tendon and muscle. In this article, these pathways are critically reviewed and discussed with various management strategies of RCLs. The article also highlights the immunobiological responses following the RCL and the inherent repair mechanisms elicited by the body. The greatest difficulty in treating this pathology is that the muscle can undergo irreversible fatty infiltration in the setting of chronic tears that is associated with poor surgical outcomes. The article also investigates the key molecular pathways of the muscle homeostasis (mTOR, Rho kinase, AMPK, and Ca(2+)) with the energy metabolism to propose a possible mechanism for fatty infiltration. Future research is warranted to target the key players of these pathways in the management of fatty infiltration and thus RCL.

Shoulder Conditions: Diagnosis and Treatment Guideline

The following guideline covers a wide array of shoulder conditions seen in the workers' compensation, as well as the nonworkers' compensation, population. The guideline is intended to help establish work relatedness and aid in making the diagnosis of shoulder injuries and degenerative conditions. It also provides a nonoperative and operative guideline for the treatment of several shoulder conditions, not limited to rotator cuff tears, subacromial impingement syndrome, acromioclavicular arthritis and dislocations, as well as glenohumeral arthritis.

Healing of rotator cuff tendons using botulinum toxin A and immobilization in a rat model

Background

We evaluated effects of botulinum toxin A (Botox) and cast immobilization on tendon healing in a rat model. Injection of Botox into rat supraspinatus was hypothesized to reduce muscle active force and improved healing.

Methods

Eighty-four supraspinatus tendons were surgically transected and repaired in 42 Sprague-Dawley rats (transosseous technique). After repair, supraspinatus muscle was injected with saline or Botox (3 or 6 U/kg). Half the shoulders were cast-immobilized for the entire postoperative period; half were allowed free cage activity. Histology was examined at 2, 4, 8, and 12 weeks. A healing zone cross-sectional area was measured, and biomechanical testing of repair strength and tendon viscoelastic properties was conducted at 4 and 12 weeks.

Results

Botox alone and cast immobilization alone exhibited increased ultimate load compared with controls (saline injection, no immobilization) at 4 weeks. No difference in ultimate load occurred between Botox-only and cast-only groups. At 12 weeks, the Botox (6 U/kg) plus cast immobilization group was significantly weakest (p < 0.05). A trend was shown toward decreased healing zone cross-sectional areas in casted groups.

Conclusions

Supraspinatus Botox injection after rotator cuff repair might help protect the repair. However, cast immobilization plus Botox administration is harmful to rotator cuff healing in a rat tendon model.

Rotator cuff repair augmentation in a rat model that combines a multilayer xenograft tendon scaffold with bone marrow stromal cells

HYPOTHESIS

A composite of multilayer tendon slices (COMTS) seeded with bone marrow stromal cells (BMSCs) may impart mechanical and biologic augmentation effects on supraspinatus tendon repair under tension, thereby improving the healing process after surgery in rats.

METHODS

Adult female Lewis rats (n = 39) underwent transection of the supraspinatus tendon and a 2-mm tendon resection at the distal end, followed by immediate repair to its bony insertion site under tension. Animals received 1 of 3 treatments at the repair site: (1) no augmentation, (2) COMTS augmentation alone, or (3) BMSC-seeded COMTS augmentation. BMSCs were labeled with a fluorescent cell marker. Animals were euthanized 6 weeks after surgery, and the extent of healing of the repaired supraspinatus tendon was evaluated with biomechanical testing and histologic analysis.

RESULTS

Histologic analysis showed gap formation between the repaired tendon and bone in all specimens, regardless of treatment. Robust fibrous tissue was observed in rats with BMSC-seeded COMTS augmentation; however, fibrous tissue was scarce within the gap in rats with no augmentation or COMTS-only augmentation. Labeled transplanted BMSCs were observed throughout the repair site. Biomechanical analysis showed that the repairs augmented with BMSC-seeded COMTS had significantly greater ultimate load to failure and stiffness compared with other treatments. However, baseline (time 0) data showed that COMTS-only augmentation did not increase mechanical strength of the repair site.

CONCLUSION

Although the COMTS scaffold did not increase the initial repair strength, the BMSC-seeded scaffold increased healing strength and stiffness 6 weeks after rotator cuff repair in a rat model.

COMPARATIVE ANALYSIS ON THE RESULT FOR ARTHROSCOPIC ROTATOR CUFF SUTURE BETWEEN SMOKING AND NON-SMOKING PATIENTS

Objective: To comparatively analyze the results from arthroscopic rotator cuff suture between smoking and non-smoking patients. Methods: A group of 286 patients who underwent arthroscopic suturing of primary rotator cuff injuries between June 12, 2002, and May 14, 2008, was analyzed. The patients included in the study were evaluated using the UCLA scale, with a minimum follow-up of 12 months and average of 56.52 months. The variables studied were age, sex, side operated, dominance, profile of cigarette use and UCLA index. Results: This study evaluated a total of 205 patients. Mean age (p = 0.289) and sex (p = 0.124) were analyzed statistically between the smoking and non-smoking patients and the two groups were considered to be similar. The average UCLA score for the non-smoking patients (143) was 34 (32 to 35). The average UCLA score for the smoking patients (51) was 33 (29 to 35). There was no statistically significant difference in UCLA score (p = 0.123) between the smoking and non-smoking patients. For the purposes of statistical analysis, we grouped the small and medium tears (107) and compared these with the large and extensive tears (80), between smokers and non-smokers. There was no statistically significant difference using the Mann-Whitney test regarding the small and medium tears (p = 818). There was a statistically significant difference using the Mann-Whitney test regarding the large and extended tears, between the smoking and non-smoking patients, such that the non-smokers showed better UCLA scores (p = 0.038). Conclusion: The results from arthroscopic suturing of large and extensive rotator cuff injuries are inferior among smoking patients.

Rotator Cuff Tendinopathy: Navigating the Diagnosis-Management Conundrum

Synopsis The hallmark characteristics of rotator cuff (RC) tendinopathy are pain and weakness, experienced most commonly during shoulder external rotation and elevation. Assessment is complicated by nonspecific clinical tests and the poor correlation between structural failure and symptoms. As such, diagnosis is best reached by exclusion of other potential sources of symptoms. Symptomatic incidence and prevalence data currently cannot be determined with confidence, primarily as a consequence of a lack of diagnostic accuracy, as well as the uncertainty as to the location of symptoms. People with symptoms of RC tendinopathy should derive considerable comfort from research that consistently demonstrates improvement in symptoms with a well-structured and graduated exercise program. This improvement is equivalent to outcomes reported in surgical trials, with the additional generalized benefits of exercise, less sick leave, a faster return to work, and reduced costs to the health care system. This evidence covers the spectrum of conditions that include symptomatic RC tendinopathy and atraumatic partial- and full-thickness RC tears. The principles guiding exercise treatment for RC tendinopathy include relative rest, modification of painful activities, an exercise strategy that initially does not exacerbate pain, controlled reloading, and gradual progression from simple to complex shoulder movements. Evidence also exists for a specific exercise program being beneficial for people with massive inoperable tears of the RC. Education is an essential component of rehabilitation, and attention to lifestyle factors (smoking cessation, nutrition, stress, and sleep management) may enhance outcomes. Outcomes may also be enhanced by subgrouping RC tendinopathy presentations and directing treatment strategies according to the clinical presentation and the patient's response to shoulder symptom modification procedures outlined herein. There are substantial deficits in our knowledge regarding RC tendinopathy that need to be addressed to further improve clinical outcomes. J Orthop Sports Phys Ther 2015;45(11):923-937. Epub 21 Sep 2015. doi:10.2519/jospt.2015.5941.

Safety and Efficacy of Nicotine Replacement Therapy in the Perioperative Period: A Narrative Review

Patients who smoke cigarettes are at increased risk for development of complications both during and after surgical procedures, including respiratory, cardiac, and healing-related complications. Abstinence from smoking can considerably reduce these risks. Pharmacotherapy, including nicotine replacement therapy (NRT), is an important component of efficacious tobacco use interventions. However, the use of NRT in the perioperative period is controversial. In this narrative review, we discuss the current evidence for the efficacy and safety of NRT in patients scheduled for surgical procedures, with emphasis on evidence from human studies. We performed a literature search for articles published from January 1, 1990, through May 1, 2015, in the PubMed online database using various permutations of the Medical Subject Headings terms surgery; surgical procedures, operative; nicotine; and smoking cessation. Studies were selected for inclusion according to their relevance to the preclinical and clinical evidence pertaining to how NRT affects surgical outcome and long-term rates of abstinence from tobacco. There is strong evidence that NRT enhances the efficacy of tobacco use interventions. Some preclinical studies suggest that nicotine in high doses that exceed those produced by NRT decreases the viability of skin flaps. Although the available data are limited, there is no evidence from human studies that NRT increases the risk of healing-related or cardiovascular complications. Individual clinical trials of tobacco use interventions that include NRT have revealed either no effect or a reduction in complication rates. Therefore, given the benefits of smoking abstinence to both perioperative outcomes and long-term health and the efficacy of NRT in achieving and maintaining abstinence, any policies that prohibit the use of NRT in surgical patients should be reexamined.

Posterior Soft Tissue Repair After Primary THA is Durable at Mid-term Followup: A Prospective MRI Study

BACKGROUND

The enhanced posterior soft tissue repair has reduced the frequency of dislocation after primary THA performed through the posterolateral approach. However, the long-term integrity of the repair is unknown and could influence surgeon choice regarding surgical technique and THA approach.

QUESTIONS/PURPOSES

We asked: (1) What is the durability of the enhanced posterior soft tissue repair at a minimum of 49 months using MRI to evaluate soft tissue to bone integrity? (2) How does the appearance of the posterior soft tissues change during this time? (3) Are there patient characteristics associated with the long-term imaging appearance of the posterior repair?

METHODS

All patients without a contraindication for MRI who were undergoing unilateral primary uncemented THA through a posterior approach between February and May 2005 were eligible for inclusion. Ninety percent consented to participate (36 of 40 patients), and 30 patients were followed prospectively with MRI postoperatively and again at 3 months; of those, 22 (73%; 12 men, 10 women) completed the study by having another MRI study at a minimum of 49 months (mean, 51 months; range, 49-59 months). Each patient underwent metal-artifact-reduction sequence MRI to evaluate the integrity of the posterior soft tissues, which had been repaired anatomically during primary THA at a minimum of 4 years earlier. The results were compared with those of prior MR images obtained immediately after surgery and at 3 months postoperatively. All patients were given a self-reported modified Harris hip score at the time of the most recent MRI study (maximum score = 81).

RESULTS

At latest followup, 21 of 22 (96%) patients had a posterior capsule in contact with bone, and 21 of 22 (96%) had an intact quadratus femoris. Twenty-one patients (96%) had soft tissue or a scar from the piriformis and conjoined tendons in continuity with bone. In these cases, the interface between the piriformis and conjoined tendons and the greater trochanter observed immediately postoperatively and at 3 months postoperatively became filled with hypointense tissue, with signal characteristics similar to tendon. Time from surgery was most associated with changes in native tendon-to-bone distances (p < 0.001) and MRI signal intensity of the repair (p < 0.001).

CONCLUSIONS

At followup of just more than 4 years, the posterior capsule and quadratus femoris most often were healed to bone. In the majority of patients, scar tissue between the piriformis and conjoined tendons and bone matured to achieve orientation and signal intensity resembling native tendon. We believe the enhanced posterior soft tissue repair facilitates this process. Our results provide a plausible explanation for improved postoperative stability observed in patients receiving an enhanced soft tissue repair compared with those in whom a repair is not performed.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Chronic Degeneration Leads to Poor Healing of Repaired Massive Rotator Cuff Tears in Rats

BACKGROUND

Chronic rotator cuff tears present a clinical challenge, often with poor outcomes after surgical repair. Degenerative changes to the muscle, tendon, and bone are thought to hinder healing after surgical repair; additionally, the ability to overcome degenerative changes after surgical repair remains unclear.

PURPOSE/HYPOTHESIS

The purpose of this study was to evaluate healing outcomes of muscle, tendon, and bone after tendon repair in a model of chronic rotator cuff disease and to compare these outcomes to those of acute rotator cuff injuries and repair. The hypothesis was that degenerative rotator cuff changes associated with chronic multitendon tears and muscle unloading would lead to poor structural and mechanical outcomes after repair compared with acute injuries and repair.

STUDY DESIGN

Controlled laboratory study.

METHODS

Chronic rotator cuff injuries, induced via detachment of the supraspinatus (SS) and infraspinatus (IS) tendons and injection of botulinum toxin A into the SS and IS muscle bellies, were created in the shoulders of rats. After 8 weeks of injury, tendons were surgically reattached to the humeral head, and an acute, dual-tendon injury and repair was performed on the contralateral side. After 8 weeks of healing, muscles were examined histologically, and tendon-to-bone samples were examined microscopically, histologically, and biomechanically and via micro-computed tomography.

RESULTS

All repairs were intact at the time of dissection, with no evidence of gapping or ruptures. Tendon-to-bone healing after repair in our chronic injury model led to reduced bone quality and morphological disorganization at the repair site compared with acute injuries and repair. SS and IS muscles were atrophic at 8 weeks after repair of chronic injuries, indicating incomplete recovery after repair, whereas SS and IS muscles exhibited less atrophy and degeneration in the acute injury group at 8 weeks after repair. After chronic injuries and repair, humeral heads had decreased total mineral density and an altered trabecular structure, and the repair had decreased strength, stiffness, and toughness, compared with the acute injury and repair group.

CONCLUSION

Chronic degenerative changes in rotator cuff muscles, tendons, and bone led to inferior healing characteristics after repair compared with acute injuries and repair. The changes were not reversible after repair in the time course studied, consistent with clinical impressions.

CLINICAL RELEVANCE

High retear rates after rotator cuff repair are associated with tear size and chronicity. Understanding the mechanisms behind this association may allow for targeted tissue therapy for tissue degeneration that occurs in the setting of chronic tears.

Factors affecting healing after arthroscopic rotator cuff repair

Rotator cuff repair has been shown to have good long-term results. Unfortunately, a significant proportion of repairs still fail to heal. Many factors, both patient and surgeon related, can influence healing after repair. Older age, larger tear size, worse muscle quality, greater muscle-tendon unit retraction, smoking, osteoporosis, diabetes and hypercholesterolemia have all shown to negatively influence tendon healing. Surgeon related factors that can influence healing include repair construct-single vs double row, rehabilitation, and biologics including platelet rich plasma and mesenchymal stem cells. Double-row repairs are biomechanically stronger and have better healing rates compared with single-row repairs although clinical outcomes are equivalent between both constructs. Slower, less aggressive rehabilitation programs have demonstrated improved healing with no negative effect on final range of motion and are therefore recommended after repair of most full thickness tears. Additionally no definitive evidence supports the use of platelet rich plasma or mesenchymal stem cells regarding improvement of healing rates and clinical outcomes. Further research is needed to identify effective biologically directed augmentations that will improve healing rates and clinical outcomes after rotator cuff repair.

Rotator cuff tear: A detailed update

Rotator cuff tear has been a known entity for orthopaedic surgeons for more than two hundred years. Although the exact pathogenesis is controversial, a combination of intrinsic factors proposed by Codman and extrinsic factors theorized by Neer is likely responsible for most rotator cuff tears. Magnetic resonance imaging remains the gold standard for the diagnosis of rotator cuff tears, but the emergence of ultrasound has revolutionized the diagnostic capability. Even though mini-open rotator cuff repair is still commonly performed, and results are comparable to arthroscopic repair, all-arthroscopic repair of rotator cuff tear is now fast becoming a standard care for rotator cuff repair. Appropriate knowledge of pathology and healing pattern of cuff, strong and biological repair techniques, better suture anchors, and gradual rehabilitation of postcuff repair have led to good to excellent outcome after repair. As the healing of degenerative cuff tear remains unpredictable, the role of biological agents such as platelet-rich plasma and stem cells for postcuff repair augmentation is still under evaluation. The role of scaffolds in massive cuff tear is also being probed.

Resistance to cigarette smoke is increased in periodontal ligament cells by attachment to collagen and fibronectin

BACKGROUND

The toxic effects of cigarette smoke often presents in smokers as increased incidence and severity of periodontal disease. These patients demonstrate symptomatic inflammation, increased probing depth, and tooth loss likely attributable to the direct effects of cigarette smoke on periodontal ligament (PDL) fibroblasts. The goal of this in vitro study is to investigate the direct effects of smoking on PDL fibroblasts, focusing on cell-extracellular matrix (ECM) interactions and cell survival.

METHODS

PDL cells were plated for various times on tissue culture plastic, PDL-derived ECMs, collagen Type I, or fibronectin. Cells were exposed to various concentrations of cigarette smoke extract (CSE) at different times during the cell attachment process. Subsequently, cell survival was quantified using calcein-acetoxymethyl ester compound and a fluorescent plate reader.

RESULTS

After exposure to CSE, PDL cell survival increased with increased cell attachment time to plastic. These observations were independent of soluble factors present in PDL cell-conditioned media. PDL-derived ECMs and collagen Type I-pretreated plates promoted increased cell survival after 1 day of cell attachment. Fibronectin-pretreated plates demonstrated increased cell survival after 3 days of cell attachment.

CONCLUSIONS

Cell-ECM interactions increase survival of PDL cells exposed to CSE. It is suggested that the increased survival is attributable to PDL cells altering their ECM, potentially by depositing collagen and fibronectin. This may imply that cells embedded in an ECM would be more resistant to the toxic effects of cigarette smoke, leading to increased cell death near the exposed edges of a wound.

Comparative analysis on arthroscopic sutures of large and extensive rotator cuff injuries in relation to the degree of osteopenia

OBJECTIVE

To analyze the results from arthroscopic suturing of large and extensive rotator cuff injuries, according to the patient's degree of osteopenia.

METHOD

138 patients who underwent arthroscopic suturing of large and extensive rotator cuff injuries between 2003 and 2011 were analyzed. Those operated from October 2008 onwards formed a prospective cohort, while the remainder formed a retrospective cohort. Also from October 2008 onwards, bone densitometry evaluation was requested at the time of the surgical treatment. For the patients operated before this date, densitometry examinations performed up to two years before or after the surgical treatment were investigated. The patients were divided into three groups. Those with osteoporosis formed group 1 (n = 16); those with osteopenia, group 2 (n = 33); and normal individuals, group 3 (n = 55).

RESULTS

In analyzing the University of California at Los Angeles (UCLA) scores of group 3 and comparing them with group 2, no statistically significant difference was seen (p = 0.070). Analysis on group 3 in comparison with group 1 showed a statistically significant difference (p = 0.027).

CONCLUSION

The results from arthroscopic suturing of large and extensive rotator cuff injuries seem to be influenced by the patient's bone mineral density, as assessed using bone densitometry.

Scapholunate interosseous ligament injuries: a retrospective review of treatment and outcomes in 82 wrists

PURPOSE

To compare outcomes of treatment for scapholunate instability between acute (< 6 wk from injury) and chronic (> 6 wk) injuries, between complete and partial tears, and among surgical techniques; identify risk factors for surgical failure; and compare ligament reconstruction with repair with or without capsulodesis in the chronic period.

METHODS

We performed a retrospective chart review of 82 primary scapholunate interosseous ligament surgeries, with median follow-up of 150 days. A total of 27 patients underwent surgery in the acute period and 50 in the chronic period. (In 5 patients we were unable to determine acuity or chronicity of injury.) In the chronic period, 16 patients underwent repair with or without capsulodesis, 27 underwent ligament reconstruction, and 7 underwent other procedures.

RESULTS

Surgical intervention in the acute setting involved more complex injuries, most commonly used direct repair, and produced a significantly lower failure rate than chronic intervention. In the chronic setting, the most common technique was ligament reconstruction, which produced superior radiographic outcomes compared with repair with or without capsulodesis. Isolated scapholunate interosseous ligament injuries undergoing chronic surgical intervention composed the majority of failures. Workers' compensation status and chronic intervention were significant risk factors for failure.

CONCLUSIONS

For chronic injuries, ligament reconstruction produced better radiographic outcomes than repair with or without capsulodesis. Acute intervention (within 6 wk) was preferable to chronic intervention for scapholunate interosseous ligament injuries, and a substantial number of isolated injuries failed to receive treatment in the acute period.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic III.

Rotator cuff tear degeneration and cell apoptosis in smokers versus nonsmokers

PURPOSE

The purpose of this study was to assess the effect of smoking on supraspinatus tendon degeneration, including cellular alterations, proliferation, and apoptosis of tendon cells.

METHODS

Supraspinatus tendon samples of 10 smokers and 15 nonsmokers with full-thickness tears were compared, focusing on the severity of tendon histopathology including apoptosis (programmed cell death), cellularity, and proliferation. Immunohistochemistry was used to assess the density of apoptotic cells and proliferation. The extent of tendon degeneration was classified according to a revised version of the Bonar tendon histopathology score.

RESULTS

The smokers were younger (P = .01). The symptom duration among smokers was longer (P < .05). The supraspinatus tendons from the smokers presented significantly more advanced degenerative changes (Bonar score, 13.5 [interquartile range, 1.4] v 9 [interquartile range, 3]; P < .001). The smokers' tendons showed increased density of apoptotic cells (0.108 [SE, 0.038] v 0.0107 [SE, 0.007]; P = .024) accompanied by reduced tenocyte density (P = .019) and upregulation of proliferative activity (P < .0001).

CONCLUSIONS

Smoking is associated with worsened supraspinatus tendon histopathology and increased apoptosis.

CLINICAL RELEVANCE

Pronounced degenerative changes, reduced tendon cellularity, and increased apoptosis may indicate reduced tendon healing capacity in smokers.

The use of video before arthroscopic shoulder surgery to enhance patient recall and satisfaction: a randomized-controlled study

BACKGROUND

Historically, the preoperative consultation has consisted of a discussion between patient and surgeon. There is a growing literature describing efforts to integrate multimedia into surgical patient education. This study aimed to assess the efficacy of an educational video tutorial on early learning of information specific to patients undergoing shoulder arthroscopy when it was used as an adjunct to the standard preoperative consultation.

METHODS

This study was a surgeon-blinded, randomized controlled trial involving 40 consecutive patients requiring shoulder arthroscopy. After a preoperative consultation with an orthopaedic surgeon, patients were randomized in a 1:1 ratio to either a control group or a treatment group. The treatment group viewed a 10-minute video, which covered the expected preoperative, intraoperative, and postoperative experience. Immediately afterward, both groups completed a questionnaire measuring satisfaction and recall of information received. All patients completed a second questionnaire at the first postoperative visit that assessed overall satisfaction with their experience.

RESULTS

Thirty-four patients were available for follow-up. The video group (N = 15) answered 87% of the knowledge questions correctly, whereas the control group (N = 19) answered only 56% (P = .000). There was stronger agreement in the video group that the preoperative consultation contained an appropriate amount of information (P = .039). Postoperatively, there was agreement that the video was an effective preparation tool for all stages of the surgical experience. However, there was no difference between the groups in satisfaction with their overall surgical experience.

CONCLUSIONS

Video can enhance patients' operative experiences and improve their retained knowledge when it is used as an adjunct to the preoperative consultation.

LEVEL OF EVIDENCE

Basic science, education methodology study, devices to improve learning.

Influence of corticoids on healing of the rotator cuff of rats - biomechanical study

Objective

to compare healing strength of the infraspinatus tendon of rats with corticoid inoculation, regarding maximum tension, maximum force and rupture force, after injury and experimental repair.

Methods

a total of 60 Wistar rats were subjected to tenotomy of the infraspinatus tendon, which was then sutured. Before the surgery, they were divided into a control group (C) inoculated with serum and a study group (S) inoculated with corticoids over the tendon. After repair, the rats were sacrificed in groups of 10 individuals in the control group and 10 in the study group at the times of one week (C1 and S1), three weeks (C3 and S3) and five weeks (C5 and S5). The rats were dissected, separating out the infraspinatus tendon with the humerus. The study specimens were subjected to a traction test, with evaluation of the maximum tension (kgf/cm²), maximum force (kgf) and rupture force (kgf), comparing the study group with the respective control groups.

Results

among the rats sacrificed one week after the procedure, we observed greater maximum tension in group C1 than in group S1. The variables of maximum force (kgf) and rupture force did not differ statistically between the groups investigated. In the same way, among the rats sacrificed three weeks after the procedure, group C3 only showed greater maximum tension than group S3 (p = 0.007), and the other variables did not present differences. Among the rats sacrificed five weeks after the procedure (C5 and S5), none of the parameters studied presented statistical differences.

Conclusion

we concluded that corticoid diminished the resistance to maximum tension in the groups sacrificed one and three weeks after the procedure, in comparison with the respective control groups. The other parameters did not show differences between the study and control groups.

Platelet-rich plasma for enhancing surgical rotator cuff repair: evaluation and comparison of two application methods in a rat model

PURPOSE

Platelet-rich plasma (PRP) is a natural concentrate of autologous growth factors now being widely tested in different fields of medicine for its potential in enhancing the regeneration of tissue with low healing potential. However, studies of PRP in enhancing rotator cuff repair have been contradictory, perhaps because of how PRP is administered. The purpose of this study is to evaluate the effect of PRP and compare two different application methods of PRP on rotator cuff healing.

METHODS

The supraspinatus tendons of 48 mature, male Wistar-Albino rats were detached from their insertion on the humerus. The animals were divided into four groups: (1) no repair, (2) primary repair, (3) repair plus PRP injections into the tendon-bone interface, and (4) repair plus PRP absorbed from a sponge carrier to the tendon-bone interface. The tendons were evaluated biomechanically and histologically at week 8.

RESULTS

Cuffs repaired with PRP had significantly greater mean (SD) load-to-failure rates [11.1 (6.5) and 11.6 (3.9) N; P < 0.05] and stiffness [3.5 (2.3) and 1.6 (0.75) N; P < 0.05] than did cuffs repaired without PRP. The groups receiving PRP did not differ significantly on these variables. Histological evaluation showed no significant differences among the four groups.

CONCLUSIONS

The application of PRP, independent of the application method, significantly improved biomechanical properties at the rotator cuff tendon-bone interface. The type of application, injection or absorption from a sponge did not influence the effect of PRP on rotator cuff healing.

Tendon transfers-how do they work? Planning and implementation

The purpose of this article is to update the orthopedic community on the planning and implementation of tendon transfers in the foot and ankle. This information will serve to reinforce those principles and factors that are inherent in successful performance of tendon transfer. In addition, the authors highlight recent updates that impact decision-making for these procedures.

Effect of Poloxamer 407 as a carrier vehicle on rotator cuff healing in a rat model

BACKGROUND

In vivo studies showing the effects of biologic healing-promoting factors on tendon-to-bone healing after rotator cuff repair have focused only on biologic healing-promoting factors and have not taken into consideration the effect of the carrier vehicle. Moreover, most studies have evaluated the healing process using different carrier vehicles, each of which may have specific effects on tendon healing. This may explain the large variability seen in outcomes in research studies. In this study, we investigated the effects of Poloxamer 407 as a carrier vehicle on rotator cuff healing at the repair site and compared it with those of a collagen sponge, which is a commonly used carrier vehicle.

METHODS

Fifty-seven adult male Sprague-Dawley rats underwent detachment and immediate repair of the bilateral supraspinatus tendons. Rats were randomly assigned to three groups: repair only, repair with collagen sponge, and repair with Poloxamer 407. The repairs were evaluated at 1, 2, 4, and 8 weeks after surgery with histological analysis and biomechanical testing.

RESULTS

At 4 weeks, more cellular organization, a greater number of collagen fibers, and increased maturity of collagen fibers were observed in the repair with Poloxamer 407 group than in the other groups. The repair with collagen sponge group had delayed development and collagen fiber maturation. Significant differences in the biomechanical properties were found between groups at 4 weeks. Stiffness in the case of the repair with Poloxamer 407 group was significantly higher than that in the repair with collagen sponge group. The modulus was significantly lower in the repair with collagen sponge group than in the repair only group. However, the use of Poloxamer 407 versus the collagen sponge did not significantly affect the biomechanical properties of the repaired tendons at 8 weeks.

CONCLUSIONS

Carrier vehicles may have differing effects at the early stages of rotator cuff healing. The use of Poloxamer 407 as a carrier vehicle may be useful for promoting the early stages of healing and for maintaining the initial biomechanical properties of the repaired rotator cuff tendon.