Robert M. Hollinshead

Matrix Metalloproteinase and Tissue Inhibitor of Matrix Metalloproteinase mRNA Levels Are Specifically Altered in Torn Rotator Cuff Tendons

Background Rotator cuff tears are a cause of pain and disability in the shoulder. The molecular changes associated with rotator cuff tearing are unclear. A subset of matrix metalloproteinases and tissue inhibitors of metalloproteinase, which are involved in extracellular matrix remodeling and degradation, were evaluated. Hypothesis There would be an increase in the mRNA level of spcific matrix metalloproteinase and a decrease in the mRNA level of specific tissue inhibitors of metalloproteinase in rotator cuff tendon tissue obtained from patients with rotator cuff tears. Study Design Controlled laboratory study. Methods Tissue was obtained from 10 patients undergoing rotator cuff repair for full-thickness rotator cuff tears. Also, tissue was obtained from cadaveric specimens with no gross evidence of rotator cuff tearing. Reverse transcription polymerase chain reaction was performed for the collagenases (MMP-1, MMP-8, MMP-13), the stromelysins (MMP-3, MMP-10, MMP-11), and the tissue inhibitors of metalloproteinase (TIMP-1, TIMP-2, TIMP-3, TIMP-4). Western blotting was performed to confirm the mRNA changes demonstrated in collagenase-3 (MMP-13). Results There was a significant increase in collagenase-3 (MMP-13) mRNA levels, a decrease in stromelysin-1 (MMP-3) mRNA levels, and a decrease in tisue inhibitor of metalloproteinase-2, -3, and -4 mRNA levels. Western blotting demonstrated an increase in the active form of collagenase-3 (MMP-13) in rotator cuff tendon tears. Conclusions The mRNA levels of specific matrix metalloproteinases and tissue inhibitors of metalloproteinase are altered in torn rotator cuff tendons. Clinical Relevance With the known action of the matrix metalloproteinases and tissue inhibitors of metalloproteinase in extra-cellular matrix remodeling, these findings suggest that their roles in remodeling of rotator cuff tears should be further investigated.

A Randomized Clinical Trial Comparing Open to Arthroscopic Acromioplasty With Mini-Open Rotator Cuff Repair for Full-Thickness Rotator Cuff Tears: Disease-Specific Quality of Life Outcome at an Average 2-Year Follow-Up

Background Rotator cuff tears affect patients’ quality of life. The evolution toward less invasive operative techniques for rotator cuff repair requires appropriate comparisons with the standard open procedure, using validated outcomes in a randomized fashion. Hypothesis There is no difference in disease-specific quality of life outcomes at 2 years between an open surgical repair (open) versus an arthroscopic acromioplasty with mini-open (scope mini-open) repair for patients with full-thickness rotator cuff tears. Study Design Randomized controlled trial; Level of evidence, 1. Methods Patients with unremitting pain, failed nonoperative treatment, and imaging indicating full-thickness rotator cuff tears were included in the study. Massive irreparable cuff tears were excluded. Patients were assessed using the disease-specific Rotator Cuff-Quality of Life index, which produces a maximum score of 100, representing a high quality of life. Secondary shoulder-specific outcomes (American Shoulder and Elbow Society, Shoulder Rating Questionnaire, and Functional Shoulder Elevation Test) were also measured at baseline, 3 and 6 months, and 1 and 2 years. Results The mean Rotator Cuff-Quality of Life scores at an average follow-up of 28 months were not statistically different: open, 86.9 (95% confidence interval: 81.8–92.0); and scope mini-open, 87.2 (95% confidence interval: 80.6–93.8). At 3 months, the patients who underwent scope mini-open showed statistically significantly better outcomes (55.6 vs 71.3; P = .005). The baseline to 3-month difference in Rotator Cuff-Quality of Life scores between the scope mini-open and open groups was also statistically significant. Conclusion Patient outcomes improved from baseline to all postoperative measurement intervals. There was no difference in outcome at 1 and 2 years after surgery between the scope mini-open and open procedures. The quality of life of patients undergoing the arthroscopic acromioplasty with mini-open rotator cuff repair improved statistically significantly and clinically at 3 months compared with the open group.

Semitubular blade plate fixation in proximal humeral fractures: A biomechanical study in a cadaveric model

This study was undertaken to compare the fixation of the semitubular blade plate with that of the AO T plate. Cadaveric humeri (n=12 pairs) from an elderly population (41 to 89 years) had either a blade plate (n=12) or a T plate (n=12) fixed to them, subsequent to which a transverse osteotomy was performed. Mechanical testing in tension was performed in 1 series (n=5, blade plate; n=5, T plate) by applying a single maximal load to failure and in a second series (n=7, blade plate; n=7, T plate) by applying submaximal cyclic loading before failure was induced. Results showed that the fixation provided by the semitubular blade plate was significantly better (P < .05) than that of the T plate in those specimens subjected to submaximal cyclic loading before failure (series 2). This latter testing method contains some component of the clinical situation compared with monotonic distraction to failure. Based on these results plus favorable clinical results reported in the literature, the semitubular blade plate is possibly a better alternative to the T plate in the management of proximal humeral fractures that require open reduction and internal fixation.

A Randomized Clinical Trial Comparing Open and Arthroscopic Stabilization for Recurrent Traumatic Anterior Shoulder Instability Two-Year Follow-up with Disease-Specific Quality-of-Life Outcomes

BACKGROUND The literature comparing open and arthroscopic repair for glenohumeral instability is conflicting. We performed a prospective, expertise-based, randomized clinical trial to compare open shoulder stabilization with arthroscopic shoulder stabilization by measuring quality-of-life outcomes and recurrence rates at two years among patients treated for traumatic anterior shoulder instability. METHODS Computer-generated, variable-block-size, concealed randomization allocated 196 patients to either the open-repair group (n = 98) or the arthroscopic-repair group (n = 98). An expertise-based randomization design was employed to avoid a differential bias in terms of physician experience. Outcomes were measured at baseline, at three and six months postoperatively, and at one and two years postoperatively with use of the Western Ontario Shoulder Instability Index (WOSI) and the American Shoulder and Elbow Surgeons (ASES) functional outcome scale. Recurrent instability was also analyzed. RESULTS There were no significant differences in outcome scores at baseline. At two years, seventy-nine patients in the open group and eighty-three patients in the arthroscopic group were available for follow-up. There was no significant difference in mean WOSI scores between the groups; the mean WOSI score (and standard deviation) for the open group was 85.2 ± 20.4 (95% confidence interval [CI] = 80.5 to 89.8), and for the arthroscopic group, 81.9 ± 19.8 (95% CI = 77.4 to 86.4); p = 0.31. There was also no significant difference in mean ASES scores: 91.4 ± 12.7 (95% CI = 88.5 to 94.4) for the open group and 88.2 ± 15.9 (95% CI = 84.6 to 91.8) for the arthroscopic group; p = 0.17. Recurrence rates at two years were significantly different: 11% in the open group and 23% in the arthroscopic group (p = 0.05). Recurrent instability was more likely in patients with a preoperative Hill-Sachs lesion and in male patients who were twenty-five years old and younger. There was no significant difference in shoulder motion between the groups at two years. CONCLUSIONS There was no difference between open and arthroscopic repair in terms of patient quality of life. Open repair resulted in a significantly lower risk of recurrence. Secondary outcome data from this trial suggest that open surgical repair may be recommended to reduce the risk of recurrent instability in younger male patients with a Hill-Sachs lesion.

Creep behavior of a rabbit model of ligament laxity after electrothermal shrinkage in vivo.

Deformation of capsular tissue under constant load (creep) may lead to recurrent laxity after thermal shrinkage for shoulder instability. We investigated the effects of thermal shrinkage in a rabbit model in which the tibial insertion of the medial collateral ligament was elevated and shifted toward the joint line to create abnormal laxity. On the right side, radiofrequency electrothermal energy was applied to the shifted ligament, while the left side served as a control. Length, laxity, mass, cross-sectional area, water content, and creep behavior of the ligament were assessed at 0 (N = 8), 3 (N = 7), and 12 (N = 6) weeks postoperatively. Laxity was reduced with thermal treatment (0.65 ± 0.31 compared with 3.33 ± 0.25 mm). After 3 weeks, ligament mass, area, and water content were significantly increased in the thermally treated group compared with the untreated controls. At 12 weeks, cyclic creep strain remained greater than that in controls (1.25% ± 0.65% compared with 0.93% ± 0.22%). Although thermal shrinkage reduced laxity, there was increased potential to creep and failure at low physiologic stresses. These findings suggest that loading of thermally treated tissues should be carefully controlled during the early phase of rehabilitation after surgery.

Comparison of magnetic resonance imaging and arthroscopy in the evaluation of shoulder pathology

Fifty-seven subjects with shoulder pain, the cause of which was not clear on clinical examination, underwent magnetic resonance imaging (MRI) and arthroscopy. With arthroscopy as the standard of reference, the accuracy of MRI for diagnosing shoulder disease was assessed. Pathologic conditions were organized into 3 groups: (1) labral tears, (2) rotator cuff disease, and (3) other pathologic conditions. At arthroscopic evaluation there were 15 labral tears, 24 rotator cuff tears, and 27 other abnormalities. MRI identified 11 of the labral injuries, with accuracy of 62%, sensitivity 73%, and specificity 58%. Rotator cuff tears were identified by MRI with accuracy of 68%, sensitivity 96%, and specificity 49%. When partial rotator cuff tears were differentiated from complete tears, only 16 of 24 injuries were identified by MRI. Nonrotator cuff, nonlabral disease was identified with accuracy of 75%, sensitivity 63%, and specificity 87%. In our center MRI does not appear to be an accurate effective tool for assessing shoulder pathologic conditions in patients in whom the clinical picture is not clear and therefore may not be of assistance in surgical planning for patients with these difficult conditions.

Cemented versus uncemented fixation of humeral components in total shoulder arthroplasty for osteoarthritis of the shoulder: a prospective, randomized, double-blind clinical trial—A JOINTs Canada Project

BACKGROUND Although cemented humeral fixation is recognized as the standard of care in total shoulder arthroplasty (TSA), uncemented fixation has the potential to provide stable fixation, decrease operative time, and simplify potential revision procedures. This prospective, randomized, double-blind clinical trial compared cemented and uncemented humeral fixation in TSA for primary shoulder osteoarthritis. METHODS Patients with primary shoulder osteoarthritis requiring replacement were screened for eligibility. After providing informed consent, subjects received baseline clinical and radiologic assessments, computed tomography scans, and standardized TSA. After glenoid component insertion, patients were randomized to either a cemented or uncemented humeral component. The primary outcome was the WOOS (Western Ontario Arthritis of the Shoulder Index) score at 2 years. Other outcomes included the Short Form 12 score, American Shoulder and Elbow Surgeons score, McMaster-Toronto Arthritis Patient Preference Disability Questionnaire, operative time, complications, and revisions. Patients were assessed by a blinded evaluator at 2 and 6 weeks and 3, 6, 12, 18, and 24 months postoperatively. RESULTS In total, 161 patients consented to be included and were randomized: 80 in the cemented group and 81 in the uncemented group. There were no significant differences in demographics or baseline evaluations between groups, except for gender. The 12-, 18-, and 24-month WOOS scores showed a significant difference in favor of the cemented group. The cemented group also had better strength and forward flexion. As expected, the operative time was significantly less for the uncemented group. CONCLUSIONS These findings provide level I evidence that cemented fixation of the humeral component provides better quality of life, strength, and range of motion than uncemented fixation.

The rotator cuff quality-of-life index predicts the outcome of nonoperative treatment of patients with a chronic rotator cuff tear.

BACKGROUND Chronic rotator cuff tears are prevalent and can be disabling. The existing literature is unclear regarding the effectiveness of nonoperative treatment. The purposes of this study were to determine whether the outcome of nonoperative treatment can be predicted on the basis of the presenting clinical characteristics and whether the outcome achieved at three months after treatment can be maintained at two years. METHODS The prospective cohort included ninety-three patients with a documented chronic full-thickness rotator cuff tear. Patients underwent a three-month supervised program of nonoperative treatment and were then evaluated by an orthopaedic surgeon. The treatment outcome was defined as a success if surgical treatment was no longer deemed appropriate by both patient and surgeon because the patient had improved considerably and was predominantly asymptomatic. The outcome was defined as a failure if the patient elected to have surgery after failing to improve and remaining symptomatic. The presenting clinical characteristics that were analyzed included age, sex, smoking status, hand dominance, duration of symptoms, onset (traumatic etiology or insidious onset), shoulder motion, external rotation strength, tear size as documented by ultrasonography or magnetic resonance imaging, and the Rotator Cuff Quality-of-Life Index (RC-QOL). RESULTS Seventy (75%) of the patients were successfully treated. Logistic regression analysis showed that the baseline RC-QOL score was a significant predictor of outcome (p = 0.017). Eighty-nine percent of patients maintained their three-month outcome at two years of follow-up. CONCLUSIONS The RC-QOL was predictive of the outcome of nonoperative treatment of patients with a chronic full-thickness rotator cuff tear. Patients in whom the nonoperative treatment was deemed successful at the conclusion of three months of treatment had a very high chance of ongoing success at two years after the initiation of treatment.

Delayed presentation: dislocation of the proximal tibiofibular joint after knee dislocation.

Attention is brought to a unique case of an anterior dislocation of the proximal tibiofibular joint detected 1 month following closed reduction of a posterior knee dislocation. Open reduction and internal fixation were necessary to achieve a stable proximal tibiofibular joint. Additional attention should be paid to the proximal tibiofibular joint when evaluating acute or chronic knee dislocation.

A multi-centre randomized controlled trial comparing electrothermal arthroscopic capsulorrhaphy versus open inferior capsular shift for patients with shoulder instability: Protocol implementation and interim performance: Lessons learned from conducting a multi-centre RCT [ISRCTN68224911; NCT00251160]

BackgroundThe shoulder is the most frequently dislocated joint in the body. Multiple causes and pathologies account for the various types of shoulder instability. Multi-directional instability (MDI) and multi-directional laxity with antero-inferior instability (MDL-AII) are similar in pathology, less common and more difficult to treat. These instabilities are caused by ligamentous capsular redundancy. When non-operative management fails for these patients, quality of life is significantly impaired and surgical treatment is required to tighten the ligaments and joint capsule. The current reference (gold) standard treatment for MDI/MDL-AII is an open inferior capsular shift (ICS) surgical procedure. An alternative treatment involves arthroscopic thermal shrinkage of redundant capsular tissue to tighten the joint. However, there is a lack of scientific evidence to support the use of this technique called, electrothermal arthroscopic capsulorrhaphy (ETAC). This trial will compare the effectiveness of ETAC to open ICS in patients with MDI and MDL-AII, using patient-based quality of life outcome assessments.MethodsThis study is a multi-centre randomized clinical trial with a calculated sample size of 58 patients (p = 0.05, 80% power). Eligible patients are clinically diagnosed with MDI or MDL-AII and have failed standardized non-operative management. A diagnostic shoulder arthroscopy is performed to confirm eligibility, followed by intra-operative randomization to the ETAC or ICS surgical procedure. The primary outcome is the disease-specific quality of life questionnaire (Western Ontario Shoulder Instability Index), measured at baseline, 3, 6, 12 and 24 months. Secondary outcomes include shoulder-specific measures (American Shoulder and Elbow Surgeons Score and Constant Score). Other outcomes include recurrent instability, complications and operative time.The outcome measurements will be compared on an intention-to-treat basis, using two-sample independent t-tests to assess statistical significance. A Generalized Estimated Equations (GEE) analysis will determine whether there is an effect over time.DiscussionThis ongoing trial has encountered unexpected operational and practical issues, including slow patient enrollment due to high intra-operative exclusion rates. However, the authors have a greater understanding of multi-directional laxity in the shoulder and anticipate the results of this trial will provide the medical community with the best scientific clinical evidence on the efficacy of ETAC compared to open ICS.