Complications of rotator cuff surgery-the role of post-operative imaging in patient care

Serial Changes of Fatty Degeneration and Clinical Outcomes after Repair of Medium-Sized Rotator Cuff Tears

Background

This study was designed to longitudinally analyze quantitative intramuscular and perimuscular fat and evaluate clinical outcomes according to healing degree after rotator cuff repair.

Methods

From June 2013 through October 2018, patients who had undergone repair due to medium-sized rotator cuff tears and serial chest computed tomography (CT) preoperatively and at early (6-12 months) and late (at least 3 years) postoperative follow-ups were included. Supraspinatus (SST) intramuscular fat fraction ratio (IFFR) and perimuscular fat fraction ratio (PFFR) were calculated using chest CT. The rotator cuff integrity was categorized as healed, smaller retear (SRT), and larger retear (LRT) by comparing the preoperative tear size and retear size in shoulder CT arthrography at postoperative follow-ups. Clinical outcomes were evaluated using the American Shoulder and Elbow Surgeons (ASES) score, the University of California at Los Angeles (UCLA) shoulder rating scale, and the Constant score preoperatively and at early and late postoperative follow-ups.

Results

In the LRT group, compared with the preoperative values, there were increases in the SST IFFR and PFFR at the early (p = 0.002 and p = 0.006, respectively) and late (p < 0.001 and p < 0.001, respectively) postoperative time points. Late postoperative clinical scores (UCLA and Constant scores) were not improved compared to preoperative scores (p = 0.156 and p = 0.094, respectively). In the SRT group, there was no difference in the mean SST IFFR and PFFR between preoperative and early postoperative time points (p = 0.766 and p = 0.180, respectively), but the late postoperative values were higher than preoperative values (p = 0.009 and p = 0.049, respectively). Late postoperative clinical scores (ASES, UCLA, and Constant scores) in the SRT group improved compared to preoperative time (p < 0.001, p < 0.001, and p = 0.016, respectively). In the healed group, compared with the preoperative values, there was no difference in the mean SST IFFR and PFFR at postoperative time points; however, the late postoperative clinical scores (ASES, UCLA, and Constant scores) were improved (all p < 0.001).

Conclusions

In the SRT group, IFFR and PFFR progressed in the late postoperative period and clinical scores improved over time. However, in the LRT group, IFFR and PFFR progressed in the early and late postoperative periods and clinical scores did not improve at the late postoperative follow-up.

High-Resolution Imaging Insights into Shoulder Joint Pain: A Comprehensive Review of Ultrasound and Magnetic Resonance Imaging (MRI)

Shoulder joint pain is a complex and prevalent clinical concern affecting individuals across various ages and lifestyles. This review delves into the pivotal role of high-resolution imaging techniques, namely ultrasound and magnetic resonance imaging (MRI), in the comprehensive assessment and management of shoulder joint pain. We explore the anatomical foundations of the shoulder, common etiologies of pain, and the significance of precise diagnosis. High-resolution imaging facilitates the identification of various shoulder pathologies and is crucial in treatment planning, surgical interventions, and long-term prognosis assessment. We examine emerging technologies, discuss challenges and limitations, and chart potential future developments, emphasizing the ongoing evolution of imaging in this critical healthcare domain. In conclusion, high-resolution imaging is an indispensable tool, continually advancing to meet the diagnostic and therapeutic needs of individuals grappling with shoulder joint pain.

Re-Tear Rates Following Rotator Cuff Repair Surgery

Aim Re-tears following rotator cuff repair surgery are a common occurrence. Previous studies have identified several factors that have been shown to increase the risk of re-tears. The purpose of this study was to evaluate the rate of re-tear following primary rotator cuff repair and to identify the factors that may contribute to this rate. Method The authors performed a retrospective review, looking at rotator cuff repair surgeries performed between May 2017 and July 2019 performed in a hospital by three specialist surgeons. All methods of repair were included. All patients' medical data, including imaging and operation records, were reviewed. Results A total of 148 patients were identified. Ninety-three males and 55 females with a mean age of 58 years (range 33-79 years). Thirty-four patients (23%) had post-operative imaging with either magnetic resonance imaging or ultrasound, where it was found that 20 (14%) had a confirmed re-tear. Of these patients, nine went on to have further repair surgery. The average age of the re-tear patients was 59 (age range 39-73) and 55% were female. The majority of the re-tears were from chronic rotator cuff injuries. This paper did not identify any correlation between smoking status or diabetes mellitus and re-tear rates. Conclusions This study indicates that re-tear after rotator cuff repair surgery is a common complication. The majority of studies find increasing age to be the biggest risk factor; however, this was not the case in our study which found females in their 50s to have the highest rate of re-tear. Additional research is required to understand what factors can contribute towards rotator cuff re-rupture rates.

A novel injectable fibromodulin-releasing granular hydrogel for tendon healing and functional recovery

A crucial component of the musculoskeletal system, the tendon is one of the most commonly injured tissues in the body. In severe cases, the ruptured tendon leads to permanent dysfunction. Although many efforts have been devoted to seeking a safe and efficient treatment for enhancing tendon healing, currently existing treatments have not yet achieved a major clinical improvement. Here, an injectable granular hyaluronic acid (gHA)-hydrogel is engineered to deliver fibromodulin (FMOD)-a bioactive extracellular matrix (ECM) that enhances tenocyte mobility and optimizes the surrounding ECM assembly for tendon healing. The FMOD-releasing granular HA (FMOD/gHA)-hydrogel exhibits unique characteristics that are desired for both patients and health providers, such as permitting a microinvasive application and displaying a burst-to-sustained two-phase release of FMOD, which leads to a prompt FMOD delivery followed by a constant dose-maintaining period. Importantly, the generated FMOD-releasing granular HA hydrogel significantly augmented tendon-healing in a fully-ruptured rat's Achilles tendon model histologically, mechanically, and functionally. Particularly, the breaking strength of the wounded tendon and the gait performance of treated rats returns to the same normal level as the healthy controls. In summary, a novel effective FMOD/gHA-hydrogel is developed in response to the urgent demand for promoting tendon healing.

Small Leucine-Rich Proteoglycans in Tendon Wound Healing

Significance: Tendon injury possesses a high morbidity rate and is difficult to achieve a satisfying prognosis with currently available treatment strategies. Current approaches used for tendon healing always lead to the formation of fibrovascular scar tissue, which significantly compromises the biomechanics of the healed tendon. Moreover, the related functional deficiency deteriorates over time with an increased injury recurrence risk. Small leucine-rich proteoglycans (SLRPs) link and interact with collagen fibrils to regulate tendon structure and biomechanics, which can provide a new and promising method in the field of tendon injury management. Recent Advances: The effect of SLRPs on tendon development has been extensively investigated. SLRP deficiency impairs tendon collagen fibril structure and biomechanic properties, while administration of SLRPs generally benefits tendon wound healing and regains better mechanical properties. Critical Issues: Current knowledge on the role of SLRPs in tendon development and regeneration mostly comes from uninjured knockout mice, and mainly focuses on the morphology description of collagen fibril profile and mechanical properties. Little is known about the regulatory mechanism on the molecular level. Future Directions: This article reviews the current knowledge in this highly translational topic and provides an evidence-based conclusion, thereby encouraging in-depth investigations of SLRPs in tendons and the development of SLRP-based treatments for desired tendon healing.

Magnetic Resonance Imaging Around Metal at 1.5 Tesla: Techniques From Basic to Advanced and Clinical Impact

ABSTRACT

During the last decade, metal artifact reduction in magnetic resonance imaging (MRI) has been an area of intensive research and substantial improvement. The demand for an excellent diagnostic MRI scan quality of tissues around metal implants is closely linked to the steadily increasing number of joint arthroplasty (especially knee and hip arthroplasties) and spinal stabilization procedures. Its unmatched soft tissue contrast and cross-sectional nature make MRI a valuable tool in early detection of frequently encountered postoperative complications, such as periprosthetic infection, material wear-induced synovitis, osteolysis, or damage of the soft tissues. However, metal-induced artifacts remain a constant challenge. Successful artifact reduction plays an important role in the diagnostic workup of patients with painful/dysfunctional arthroplasties and helps to improve patient outcome. The artifact severity depends both on the implant and the acquisition technique. The implant's material, in particular its magnetic susceptibility and electrical conductivity, its size, geometry, and orientation in the MRI magnet are critical. On the acquisition side, the magnetic field strength, the employed imaging pulse sequence, and several acquisition parameters can be optimized. As a rule of thumb, the choice of a 1.5-T over a 3.0-T magnet, a fast spin-echo sequence over a spin-echo or gradient-echo sequence, a high receive bandwidth, a small voxel size, and short tau inversion recovery-based fat suppression can mitigate the impact of metal artifacts on diagnostic image quality. However, successful imaging of large orthopedic implants (eg, arthroplasties) often requires further optimized artifact reduction methods, such as slice encoding for metal artifact correction or multiacquisition variable-resonance image combination. With these tools, MRI at 1.5 T is now widely considered the modality of choice for the clinical evaluation of patients with metal implants.

Long-term follow-up of perianchor cyst formation after rotator cuff repair

Background

Perianchor cyst formation (PCF) can occur after arthroscopic rotator cuff repair with poly-L-lactic acid (PLLA) anchors; however, little is known about PCF after all-suture anchor (ASA) use.

Methods

We reviewed patients who underwent double-row arthroscopic rotator cuff repair from 2012 to 2017 with ASAs implanted in the medial row and PLLA anchors in the lateral row. We evaluated PCF (graded on magnetic resonance imaging) and compared physical examination and functional surveys between patients with PCF (WC) and without PCF (WoC) at long-term follow-up.

Results

Among twenty-two patients (23 shoulders), 93% of PLLA anchors (vs. 79% ASA) displayed a grade 0 PCF, P = .100. No PLLA anchors had a grade 3 or 4 PCF, compared to 11% of ASAs, P = .158. At a mean postoperative follow-up time of 113 weeks, there was no significant difference between WC and WoC cohorts with regard to range of motion, rotator cuff strength, American Shoulder and Elbow Surgeons survey scores, or retear rates. However, the WoC cohort had a significantly higher University of California at Los Angeles shoulder survey score at final follow-up (34.3 WoC vs. 30.9 WC, P = .024).

Conclusion

No difference was found in PCF between ASAs and PLLA anchors. At long-term follow-up, WoC patients had significantly improved functional outcome scores, based on the University of California at Los Angeles survey, but equivalent range of motion and rotator cuff strength examinations compared with WC patients.

Assessment of postoperative acromial and subacromial morphology after arthroscopic acromioplasty using magnetic resonance imaging

OBJECTIVE

To identify the morphological characteristics of the acromion and subacromial bursal space after arthroscopic acromioplasty using magnetic resonance imaging (MRI).

MATERIALS AND METHODS

One hundred patients who received arthroscopic rotator cuff repair and acromioplasty each received at least three MRI examinations (preoperative, first immediate postoperative, and second follow-up imaging between 8 months and 1 year postoperatively). Changes over time in the thickness and morphology of the postoperative acromion as well as the subacromial bursal space were assessed. Clinical and radiological parameters were also analyzed to identify any association with changes in acromial morphology.

RESULTS

Despite minimal acromial thinning observed at the first immediate postoperative state, the acromions showed significant thinning at the second postoperative MRI, with a mean reduction of 32%. Along with acromial thinning, an exaggerated concave contour of the acromial undersurface was observed in some patients. In the subacromial space, a loculated fluid collection developed in 91% of the patients at the second postoperative follow-up. No statistically significant association was noted between postoperative acromial thickness change and clinical or radiological factors (P value > 0.05).

CONCLUSION

A significant delayed reduction in acromial thickness within approximately 1 year of arthroscopic acromioplasty is thought to be a normal postoperative feature. The simultaneous collection of a loculated, cyst-like fluid in the subacromial bursal space may be an important associated factor of postoperative acromial thinning.

Current challenges and controversies in the management of scapular fractures: a review

Fractures of the scapula are rare and usually associated with high-energy trauma. The unfavorable scapular anatomy, combined with the complexity of the approaches for fracture fixation, make the treatment challenging, even for experienced surgeons. Furthermore, the literature is controversial regarding surgical indications and rationale for treatment. The present review article was designed to address and discuss critical aspects of decision-making for the management of scapular fractures, including surgical indications and patient safety considerations.

Arthroscopic rotator cuff repair: magnetic resonance arthrogram assessment of tendon healing

BACKGROUND

Many poor outcomes after arthroscopic rotator cuff (RC) repair relate to failure of tendon healing. The purposes of this study were to provide a better understanding of the magnetic resonance arthrography (MRA) characteristics of the RC tendon repair site after arthroscopic RC repair and to examine how these findings influence patient-reported outcome measures (PROMs) and the presence of persistent symptoms.

METHODS

We reviewed 48 shoulders (13 female and 35 male patients; average age, 53.8 years) at a minimum of 6 months (average, 11.4 months) after arthroscopic RC repair (average tear size, 2.2 cm). All patients completed PROMs and underwent MRA assessment. Detailed analysis of the RC repair site was undertaken, with findings correlated with clinical outcomes and PROMs.

RESULTS

The average preoperative American Shoulder and Elbow Surgeons (ASES) score of 39.5 improved to 92.8 (P < .001). All but 6 patients (87.5%) had increased signal intensity of the involved tendon, with interstitial splits and/or delamination in 65.6%. These changes had no effect on PROMs or patient satisfaction. Significant partial-thickness tears (>50%) were observed in 7 patients (14.6%), with no effect on outcomes (average ASES score of 95.2 and satisfaction score of 9). There were 2 recurrent full-thickness tears (4.2%), and 4 patients (8.3%) had a failure in continuity. The average ASES score in these 6 cases of failure was 76 (P < .001).

CONCLUSIONS

Structural abnormalities on MRA are common after RC repair but do not always result in clinical failure. However, our results suggest that an ASES score of less than 80 may be useful when considering postoperative imaging, especially in a patient with ongoing pain more than 6 months after surgery.

Does arthroscopic preemptive extensive rotator interval release reduce postoperative stiffness after arthroscopic rotator cuff repair?: a prospective randomized clinical trial

BACKGROUND

To investigate whether preemptive extensive rotator interval (RI) release during arthroscopic rotator cuff repair (ARCR) would reduce postoperative stiffness.

METHODS

From July 2015 to September 2016, a total of 80 patients who were scheduled for ARCR were enrolled and randomly allocated into 2 groups: the preemptive extensive RI release group (group 1, n=40) and the RI nonrelease group (group 2, n=40). The American Shoulder and Elbow Surgeons scale, Constant score, Korean Shoulder Scale (KSS), visual analog scale (VAS) pain score, and range of motion (ROM) were evaluated before surgery; 3, 6, and 12 months after surgery; and at last follow-up. Magnetic resonance imaging was performed at postoperative 12 months.

RESULTS

The mean follow-up period was 26.5 months. The functional and pain scores in both groups were significantly improved at the last follow-up (P < .05). Group 1 showed a significantly higher sum of ROM with a difference of 27° and 1.6 vertebral level of internal rotation compared to group 2 at postoperative 3 months (P < .05). Constant score and KSS were significantly higher in group 1 than in group 2 at this time point (P < .05). Functional scores and ROM were not significantly different between 2 groups at postoperative 6 or 12 months or at the last follow-up (P > .05). The retear rate and pathologic change of the long head of the biceps tendon during follow-up were not significantly different between the 2 groups (P > .05).

CONCLUSION

Arthroscopic preemptive extensive RI release can reduce early postoperative shoulder stiffness after ARCR but does not significantly change the overall clinical outcome after surgery.

Imaging of Usual and Unusual Complication of Rotator Cuff Repair

Several complications may be encountered after rotator cuff (RC) repair. A thorough knowledge of surgical interventions, normal postoperative findings, and postoperative complications is crucial to provide a timely diagnosis, improving the clinical outcome of patients. Postoperative complications may involve RC, implanted device, osteochondral tissue, surgical-site infection, peripheral nerves, soft tissues, and vascular structures. In this review, we discuss the usual and unusual complications detectable after RC repair.

Tendinosis-like changes in denervated rat Achilles tendon

Background

Tendon disorders are common and lead to significant disability and pain. Our knowledge of the ‘tennis elbow’, the ‘jumpers knee’, and Achilles tendinosis has increased over the years, but changes in denervated tendons is yet to be described in detail. The aim of the present study was to investigate the morphological and biochemical changes in tendon tissue following two weeks of denervation using a unilateral sciatic nerve transection model in rat Achilles tendons.

Methods

Tendons were compared with respect to cell number, nuclear roundness, and fiber structure. The non-denervated contralateral tendon served as a control. Also, the expression of neuromodulators such as substance P and its preferred receptor neurokinin-1 receptor, NK-1R, was evaluated using real-time qRT-PCR.

Results

Our results showed that denervated tendons expressed morphological changes such as hypercellularity; disfigured cells; disorganization of the collagen network; increased production of type III collagen; and increased expression of NK-1R.

Conclusion

Taken together these data provide new insights into the histopathology of denervated tendons showing that denervation causes somewhat similar changes in the Achilles tendon as does tendinosis in rats.

Magnetic resonance imaging signal artefacts from invisible metal debris following surgery to the elbow

We report a case of exuberant artefacts on the magnetic resonance imaging scan of the elbow produced by invisible metal debris secondary to previous surgery.

Metal artefacts severely hamper magnetic resonance imaging of the rotator cuff tendons after rotator cuff repair with titanium suture anchors

BACKGROUND

The rate of retear after rotator cuff surgery is 17%. Magnetic resonance imaging (MRI) scans are used for confirmative diagnosis of retear. However, because of the presence of titanium suture anchors, metal artefacts on the MRI are common. The present study evaluated the diagnostic value of MRI after rotator cuff tendon surgery with respect to assessing the integrity as well as the degeneration and atrophy of the rotator cuff tendons when titanium anchors are in place.

METHODS

Twenty patients who underwent revision surgery of the rotator cuff as a result of a clinically suspected retear between 2013 and 2015 were included. The MRI scans of these patients were retrospectively analyzed by four specialized shoulder surgeons and compared with intra-operative findings (gold standard). Sensitivity and interobserver agreement among the surgeons in assessing retears as well as the Goutallier and Warner classification were examined.

RESULTS

In 36% (range 15% to 50%) of the pre-operative MRI scans, the observers could not review the rotator cuff tendons. When the rotator cuff tendons were assessable, a diagnostic accuracy with a mean sensitivity of 0.84 (0.70 to 1.0) across the surgeons was found, with poor interobserver agreement (kappa = 0.12).

CONCLUSIONS

Metal artefacts prevented accurate diagnosis from MRI scans of rotator cuff retear in 36% of the patients studied.

Early postoperative magnetic resonance imaging findings after arthroscopic rotator cuff repair: T2 hyperintensity of the capsule can predict reduced shoulder motion

INTRODUCTION

The purpose of this study was to investigate whether postoperative shoulder magnetic resonance imaging (MRI) findings correlate with postoperative shoulder range of motion (ROM) at about 4 months after arthroscopic rotator cuff repair (ARCR).

MATERIALS AND METHODS

Signal-intensity changes of the capsule, pericapsular soft tissue at the axillary recess, and subcoracoid fat triangle, as well as the thickness of the capsule at the axillary recess and coracohumeral ligament were assessed on preoperative and postoperative MR images of 232 patients. The ROM was evaluated preoperatively and at about 4 months after ARCR.

RESULTS

T2 hyperintensity of the capsule, pericapsular soft tissue at the axillary recess, and signal change of the subcoracoid fat triangle were detected in 155, 107, and 89 cases, respectively, on postoperative MRI. Among these cases, 129, 98, and 69 cases, respectively, showed newly developed signal changes. The mean thicknesses of the capsule and coracohumeral ligament were 1.89 ± 0.69 and 1.64 ± 0.51 mm, respectively, on preoperative MRI and 3.74 ± 1.12 and 2.42 ± 0.56 mm, respectively, on postoperative MRI. At the 4-month follow-up, the mean external rotation (ER), internal rotation (IR), abduction, forward flexion, and extension were 77, 73, 76, 83, and 82%, respectively, of the contralateral side. Newly developed T2 hyperintensity of the capsule and pericapsular soft tissue at the axillary recess on postoperative MRI significantly correlated with the postoperative limitation of ER (p = 0.039) and IR (p = 0.020).

CONCLUSIONS

Newly developed signal changes of the capsule, pericapsular soft tissue at the axillary recess, and subcoracoid fat triangle were often detected on postoperative MRI at 4 months after ARCR. Furthermore, newly developed T2 hyperintensity of the capsule and pericapsular soft tissue at the axillary recess correlated with limited ROM in ER and IR at 4 months after ARCR.

The Repaired Rotator Cuff: MRI and Ultrasound Evaluation

PURPOSE OF REVIEW

The purposes of this review were to provide an overview of the current practice of evaluating the postoperative rotator cuff on imaging and to review the salient imaging findings of the normal and abnormal postoperative rotator cuff, as well as of postoperative complications.

RECENT FINDINGS

The repaired rotator cuff frequently appears abnormal on magnetic resonance imaging (MRI) and ultrasound (US). Recent studies have shown that while the tendons typically normalize, they can demonstrate clinically insignificant abnormal imaging appearances for longer than 6 months. Features of capsular thickening or subacromial-subdeltoid bursal thickening and fluid distension were found to decrease substantially in the first 6-month postoperative period. MRI and US were found to be highly comparable in the postoperative assessment of the rotator cuff, although they had a lower sensitivity for partial thickness tears. Imaging evaluation of newer techniques such as patch augmentation and superior capsular reconstruction needs to be further investigated. MRI and US are useful in the postoperative assessment of the rotator cuff, not only for evaluation of the integrity of the rotator cuff, but also for detecting hardware complications and other etiologies of shoulder pain.

Clinical and sonographic evaluation of subpectoral biceps tenodesis with a dual suture anchor technique demonstrates improved outcomes and a low failure rate at a minimum 2-year follow-up

INTRODUCTION

The purpose of this study was to evaluate the clinical outcomes and integrity of an open subpectoral biceps tenodesis using a dual suture anchor construct.

MATERIALS AND METHODS

Patients with at least 2 years of follow-up were retrospectively evaluated for simple shoulder test (SST), American Shoulder and Elbow Surgeons (ASES) score, and visual analog scales (VAS) for pain, function and satisfaction. A physical exam assessed shoulder range of motion and elbow strength. Ultrasonography visualized construct integrity.

RESULTS

Of 43 eligible patients, 36 completed questionnaire evaluation and 22 completed an additional physical examination. Indications included superior labral anterior-posterior (SLAP) lesions (4), partial thickness tears (6), instability (6), and tenosynovitis of the biceps tendon (20). Eighteen patients (50%) had an associated rotator cuff tear. Patient-reported outcomes improved pre- vs postoperatively: ASES score (45.4 vs 78.6, P < 0.001), SST (5.1 vs 9.6, P < 0.001), pain-VAS (4.8 vs 2.0, P < 0.001), and function-VAS (4.9 vs 2.3, P < 0.001). Satisfaction-VAS was 8.3 postoperatively. Patient-reported outcomes did not differ for patients with an associated rotator cuff tear compared to those without (P ≥ 0.427). None of the physical exam measures were lower on the operative side compared to the healthy side (P ≥ 0.516). Sonographic evaluation revealed preserved integrity of the tenodesis construct in all cases. No complications were noted.

CONCLUSIONS

Subpectoral biceps tenodesis utilizing a dual suture anchor technique is a treatment option for SLAP lesions, partial thickness tears, subluxation, and tenosynovitis of the long head of the biceps with high rates of postoperative patient satisfaction, a low failure rate, and improved outcome scores. The presence of a concomitant rotator cuff tear did not influence clinical outcomes.

Post-operative rotator cuff integrity, based on Sugaya's classification, can reflect abduction muscle strength of the shoulder

PURPOSE

Magnetic resonance (MR) imaging is common in structural and qualitative assessment of the rotator cuff post-operatively. Rotator cuff integrity has been thought to be associated with clinical outcome. The purpose of this study was to evaluate the inter-observer reliability of cuff integrity (Sugaya's classification) and assess the correlation between Sugaya's classification and the clinical outcome. It was hypothesized that Sugaya's classification would show good reliability and good correlation with the clinical outcome.

METHODS

Post-operative MR images were taken two years post-operatively, following arthroscopic rotator cuff repair. For assessment of inter-rater reliability, all radiographic evaluations for the supraspinatus muscle were done by two orthopaedic surgeons and one radiologist. Rotator cuff integrity was classified into five categories, according to Sugaya's classification. Fatty infiltration was graded into four categories, based on the Fuchs' classification grading system. Muscle hypotrophy was graded as four grades, according to the scale proposed by Warner. The clinical outcome was assessed according to the constant scoring system pre-operatively and 2 years post-operatively.

RESULTS

Of the sixty-two consecutive patients with full-thickness rotator cuff tears, fifty-two patients were reviewed in this study. These subjects included twenty-three men and twenty-nine women, with an average age of fifty-seven years. In terms of the inter-rater reliability between orthopaedic surgeons, Sugaya's classification showed the highest agreement [ICC (2.1) = 0.82] for rotator cuff integrity. The grade of fatty infiltration and muscle atrophy demonstrated good agreement, respectively (0.722 and 0.758). With regard to the inter-rater reliability between orthopaedic surgeon and radiologist, Sugaya's classification showed good reliability [ICC (2.1) = 0.70]. On the other hand, fatty infiltration and muscle hypotrophy classifications demonstrated fair and moderate agreement [ICC (2.1) = 0.39 and 0.49]. Although no significant correlation was found between overall post-operative constant score and Sugaya's classification, Sugaya's classification indicated significant correlation with the muscle strength score.

CONCLUSIONS

Sugaya's classification showed repeatability and good agreement between the orthopaedist and radiologist, who are involved in the patient care for the rotator cuff tear. Common classification of rotator cuff integrity with good reliability will give appropriate information for clinicians to improve the patient care of the rotator cuff tear. This classification also would be helpful to predict the strength of arm abduction in the scapular plane.

LEVEL OF EVIDENCE

IV.

Pullout strength of cement-augmented and wide-suture transosseous fixation in the greater tuberosity

BACKGROUND

Obtaining strong fixation in low-density bone is increasingly critical in surgical repair of rotator cuff tears because of the aging population. To evaluate two new methods of improving pullout strength of transosseous rotator cuff repair in low-density bone, we analyzed the effects of 1) using 2-mm suture tape instead of no. 2 suture and 2) augmenting the lateral tunnel with cement.

METHODS

Eleven pairs of osteopenic or osteoporotic cadaveric humeri were identified by dual-energy x-ray absorptiometry. One bone tunnel and one suture were placed in the heads of 22 specimens. Five randomly selected pairs were repaired with no. 2 suture; the other six pairs were repaired with 2-mm suture tape. One side of each pair received lateral tunnel cement augmentation. Specimens were tested to suture pullout. Data were fitted to multivariate models that accounted for bone mineral density and other specimen characteristics.

FINDINGS

Two specimens were excluded because of knot-slipping during testing. Use of suture tape versus no. 2 suture conferred a 75-N increase (95% CI: 37, 113) in pullout strength (P<0.001). Cement augmentation conferred a 42-N improvement (95% CI: 10, 75; P=0.011). Other significant predictors of pullout strength were age, sex, and bone mineral density.

INTERPRETATION

We show two methods of improving the fixation strength of transosseous rotator cuff repairs in low-density bone: using 2-mm suture tape instead of no. 2 suture and augmenting the lateral tunnel with cement. These methods may improve the feasibility of transosseous repairs in an aging patient population.

[Magnetic resonance imaging findings after shoulder surgery: What the radiologist needs to know]

Even primary diagnostic evaluation of the shoulder is a challenge for radiologists. Many imaging findings that definitely indicate abnormal findings in the untreated shoulder should be evaluated carefully in postoperative patients. Artifacts caused by implants or metal abrasion pose considerable problems in postoperative magnetic resonance imaging (MRI). Classic approaches to minimizing artifacts caused by foreign bodies include using turbo spin echo sequences, increasing bandwidth, and reducing voxel size. In recent years, several vendors have developed dedicated pulse sequences for reducing metal artifacts. Different postoperative imaging findings will be encountered, depending on the kind of surgery done. This review article describes typical postoperative MRI findings, focusing on subacromial decompression, reconstruction of the rotator cuff, labrum procedures, and biceps tenodesis.

Postoperative Shoulder Imaging: Rotator Cuff, Labrum, and Biceps Tendon

Imaging interpretation of the postoperative shoulder is a challenging and difficult task for both the radiologist and the orthopedic surgeon. The increasing number of shoulder rotator cuff, labrum, and biceps tendon repairs performed in the United States also makes this task a frequent occurrence. Whether treatment is surgical or conservative, imaging plays a crucial role in patient care. Many imaging findings can be used to predict prognosis and functional outcomes, ultimately affecting treatment. In addition, evolving surgical techniques alter the normal anatomy and imaging appearance of the shoulder such that accepted findings proved to be pathologic in the preoperative setting cannot be as readily described as pathologic after surgery. An understanding of common surgical procedures of the shoulder can aid in recognizing normal expected postoperative findings and discerning common complications. Although magnetic resonance (MR) imaging and MR arthrography are widely used, implementing a multimodality imaging approach for evaluation of the postoperative shoulder can provide additional imaging information that may be decisive and vital to diagnosis. The high spatial resolution of both computed tomography with arthrography and ultrasonography makes them additional modalities to consider, especially when dealing with metal artifact. To provide an accurate radiologic interpretation of high clinical value, radiologists should approach the postoperative shoulder comprehensively with knowledge of the anatomy, surgical techniques and complications, clinical outcomes, and imaging pitfalls. ^©RSNA, 2016.

Advances in MRI around metal

The prevalence of orthopedic metal implants is continuously rising in the aging society. Particularly the number of joint replacements is increasing. Although satisfying long-term results are encountered, patients may suffer from complaints or complications during follow-up, and often undergo magnetic resonance imaging (MRI). Yet metal implants cause severe artifacts on MRI, resulting in signal-loss, signal-pileup, geometric distortion, and failure of fat suppression. In order to allow for adequate treatment decisions, metal artifact reduction sequences (MARS) are essential for proper radiological evaluation of postoperative findings in these patients. During recent years, developments of musculoskeletal imaging have addressed this particular technical challenge of postoperative MRI around metal. Besides implant material composition, configuration and location, selection of appropriate MRI hardware, sequences, and parameters influence artifact genesis and reduction. Application of dedicated metal artifact reduction techniques including high bandwidth optimization, view angle tilting (VAT), and the multispectral imaging techniques multiacquisition variable-resonance image combination (MAVRIC) and slice-encoding for metal artifact correction (SEMAC) may significantly reduce metal-induced artifacts, although at the expense of signal-to-noise ratio and/or acquisition time. Adding advanced image acquisition techniques such as parallel imaging, partial Fourier transformation, and advanced reconstruction techniques such as compressed sensing further improves MARS imaging in a clinically feasible scan time. This review focuses on current clinically applicable MARS techniques. Understanding of the main principles and techniques including their limitations allows a considerate application of these techniques in clinical practice. Essential orthopedic metal implants and postoperative MR findings around metal are presented and highlighted with clinical examples.

LEVEL OF EVIDENCE

4 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2017;46:972-991.

What can be seen after rotator cuff repair: a brief review of diagnostic imaging findings

Diagnostic imaging plays an important role in the postoperative evaluation of the rotator cuff, as pain and disability may occur or persist after treatment. Postoperative imaging is therefore of paramount importance for clinicians before planning additional treatments. Multimodality imaging of the postoperative shoulder includes radiography, magnetic resonance (MR) imaging, MR arthrography, computed tomography (CT), CT arthrography, and ultrasound. Correct interpretation of imaging findings of the postoperative shoulder necessitates that the radiologist be familiar with the various treatment strategies, their possible complications and sources of failure, knowledge of normal and abnormal postoperative findings, and awareness of the advantages and weaknesses of the different imaging techniques. Imaging findings, however, should always be correlated with the clinical presentation because postoperative imaging abnormalities do not necessarily correlate with symptoms. This manuscript is a review of some of the most common treatment strategies for rotator cuff pathology, with a focus on expected postoperative imaging findings and postoperative complications.

Magnetic resonance imaging arthrography following type II superior labrum from anterior to posterior repair: interobserver and intraobserver reliability

BACKGROUND

Arthroscopic repair of type II superior labrum from anterior to posterior (SLAP) lesions is a common surgical procedure. However, anatomic healing following repair has rarely been investigated. The intraobserver and interobserver reliability of magnetic resonance imaging arthrography (MRA) following type II SLAP repair has not previously been investigated. This is of particular interest due to recent reports of poor clinical results following type II SLAP lesion repair.

PURPOSE

To evaluate the MRA findings following arthroscopic type II SLAP lesion repair and determine its intraobserver and interobserver reliability.

STUDY DESIGN

Cohort study (diagnosis), Level of Evidence, 2.

METHODS

Twenty-five patients with an isolated type II SLAP lesion (confirmed via diagnostic arthroscopy) underwent standard suture anchor-based repair. At a mean of 25.2 months post-operatively, patients underwent a standardized MRA protocol to investigate the integrity of the repair. MRAs were independently reviewed by two radiologists and a fellowship trained shoulder surgeon. The outcomes were classified as healed SLAP repair or re-torn SLAP repair.

RESULTS

On average, 54% of MRAs were interpreted as healed SLAP repairs while 46% of MRAs were interpreted as having a re-torn SLAP repair. Overall, only 43% of the studies had 100% agreement across all interpretations. The intraobserver reliability ranged from 0.71 to 0.81 while the interobserver reliability between readers ranged from 0.13 to 0.44 (Table 1).

CONCLUSION

The intraobserver agreement of MRA in the evaluation of type II SLAP repair was substantial to excellent. However, the interobserver agreement of MRA was poor to fair. As a result, the routine use of MRA in the evaluation of type II SLAP lesion repair should be utilized with caution. A global evaluation of the patient, including detailed history and physical examination, is paramount in determining the cause of failure and one should not rely on MRA alone.