Diagnostic Value of Clinical Tests for Infraspinatus Tendon Tears.

PURPOSE: To analyze and compare the diagnostic value and interpretation of 6 established clinical tests for infraspinatus tendon tears; to assess their ability to distinguish between partial- and full-thickness tears of the infraspinatus tendon; and to investigate whether conducting multiple tests increases the precision of diagnosis. METHODS: A total of 91 patients scheduled for shoulder arthroscopy from March 2015 to April 2017 were included in the present study. To assess the sensitivity, specificity, positive and negative predictive values, accuracy, diagnostic odds ratio, positive and negative likelihood ratios, and the area under the curve (AUC), intraoperative findings were compared with the results of 6 established clinical infraspinatus tests: the hornblower's test, the drop sign, the Patte sign, the external rotation lag sign (ERLS), the resisted external rotation test (RERT), and the infraspinatus scapular retraction test. RESULTS: A significant correlation was found between the results of the drop sign (P = .02), the ERLS (P = .02), and the RERT (P = .02) and the intraoperative findings. The RERT achieved the highest AUC (0.673). Assessing muscle weakness led to the highest diagnostic precision on the RERT (AUC = 0.673) as compared with pain (AUC = 0.528) or using both criteria (AUC = 0.655). No single clinical test was found to be useful in distinguishing between partial- and full-thickness tears. The combination of at least 2 or more tests improved the diagnostic precision significantly (P ≤ .007). The combination of the RERT and the Patte sign showed the best AUC (0.681) and highest correlation with the intraoperative findings (P = .023). CONCLUSIONS: The results of the present study indicate that out of all the clinical tests investigated, the drop sign and the RERT were in isolation able to accurately diagnose tears of the infraspinatus tendon. Only muscle weakness should be considered when interpreting the RERT because of its greater AUC values and correlation with the arthroscopic findings. The present study also showed that the analyzed tests are not capable of distinguishing between partial- and full-thickness tears of the infraspinatus tendon and that the combination of at least 2 tests improved the diagnostic value. The combination of the RERT and the Patte sign showed the best AUC and highest correlation with the intraoperative findings. LEVEL OF EVIDENCE: Level II, diagnostic study, prospective comparative study.

Diagnostic Value of Clinical Tests for Supraspinatus Tendon Tears.

PURPOSE: The purpose of this study was to analyze the diagnostic value of 7 clinical tests for the diagnosis of supraspinatus tendon tears, to investigate the ability of these tests to distinguish between partial- and full-thickness tears, and to compare 3 different ways of interpreting positive test results (weakness and pain): (1) in case of pain, (2) in case of weakness, regardless if with pain or not, and (3) when any of the 2 symptoms occurs, regardless if in combination or not. Moreover, this study aimed to investigate whether a combination of tests can improve the diagnostic accuracy. METHODS: A total of 115 consecutive patients who presented with different shoulder symptoms were prospectively enrolled in the study from March 2015 to April 2017. The inclusion criterion was that a shoulder arthroscopy was scheduled. Patients with the following characteristics were excluded from the study: patients (1) with shoulder instability, (2) with adhesive capsulitis, or (3) with any history of previous shoulder surgery including rotator cuff repair or patients (4) who did not provide informed consent. To assess the sensitivity, specificity, positive and negative predictive values, accuracy, diagnostic odds ratio, positive and negative likelihood ratio, and area under the curve (AUC) of each test, the intraoperative findings were compared with the results of the preoperative clinical examination of 7 established clinical tests: the empty can test, the full can test, the zero-degree abduction test, the Whipple test, the scapular retraction test, the drop arm test, and the modified drop arm test. RESULTS: A significant correlation was found between the findings for the empty can (P = .004) and full can (P = .001) tests and the intraoperative findings, wherein the full can test achieved better AUC. Muscle weakness showed the best diagnostic precision compared with pain or using both criteria. No single clinical test was found to be useful to distinguish between partial- and full-thickness tears. A combination of at least 3 or more tests improved the diagnostic value. The combination of the empty can, the full can, and the zero-degree abduction tests showed the best AUC (0.795) and correlation with the intraoperative findings (P = .02). CONCLUSIONS: The results of the present study indicate that of all clinical tests studied, only the empty can and full can tests were effectively able to diagnose tears of the supraspinatus tendon accurately. The greater AUC and correlation with the arthroscopic findings suggest that muscle weakness should be considered the gold standard when interpreting the test results. Furthermore, the present study showed that the analyzed tests are not capable of distinguishing between partial- and full-thickness tears of the supraspinatus tendon and that the combination of at least 3 tests, including the empty can, the full can, and the zero-degree abduction tests, improved the diagnostic value significantly. In addition, the empty and full can tests have showed higher diagnostic precision and fair AUC when supraspinatus tendon tears were more than 1 cm in size. LEVEL OF EVIDENCE: Level 1, diagnostic study.

Does footprint preparation influence tendon-to-bone healing after rotator cuff repair in an animal model?

PURPOSE: The aim of this study was to investigate the influence of footprint spongialization and radiofrequency ablation on rotator cuff repair outcomes compared with an untreated group in a rat model. METHODS: We randomly assigned 189 Sprague-Dawley rats to either a spongialization, radiofrequency ablation, or untreated group. After separation of the supraspinatus tendon from the greater tubercle, the footprint was prepared by removing the cortical bone with a burr (spongialization), was prepared by ablating soft tissue with a radiofrequency ablation device, or was left unaltered (untreated). Biomechanical testing (after 7 weeks, n = 165) and histologic analysis after 1 and 7 weeks (n = 24) followed reinsertion. RESULTS: The mean load to failure was 17.51 ± 4.46 N/mm(2) in the spongialization group, 15.56 ± 4.85 N/mm(2) in the radiofrequency ablation group, and 19.21 ± 5.19 N/mm(2) in the untreated group. A significant difference was found between the spongialization and radiofrequency ablation groups (P = .0409), as well as between the untreated and radiofrequency ablation groups (P = .0014). There was no significant difference between the spongialization and untreated groups (P = .2456). The mean area of fibrocartilage transition, characterized by the presence of type II collagen, was larger after 1 and 7 weeks in the spongialization group (0.57 ± 0.1 mm(2) and 0.58 ± 0.1 mm(2), respectively) and untreated group (0.51 ± 0.1 mm(2) and 0.51 ± 0.2 mm(2), respectively) than in the radiofrequency ablation group (0.11 ± 0.1 mm(2) and 0.4 ± 0.1 mm(2), respectively) with P < .05 and P < .01. CONCLUSIONS: The results of this study show that radiofrequency ablation of the footprint results in a poor biomechanical and histologic outcome in an animal model. No preparation of the footprint has the same effect as spongialization. CLINICAL RELEVANCE: Different techniques of footprint preparation in rotator cuff repair may influence tendon-to-bone healing.

The influence of different footprint preparation techniques on tissue regeneration in rotator cuff repair in an animal model.

INTRODUCTION: Rotator cuff tears are common diseases of the upper extremity. There are no recommendations to the surgeon on how to prepare the footprint to ensure optimal tendon-to-bone healing. However, biologic augmentation using stem cells and growth factors is considered to encourage the healing process of the tendon. The aim of the study was to investigate the biomechanical and histological outcome of different footprint preparations in rotator cuff repair. MATERIAL AND METHODS: One hundred and eighty-nine Sprague-Dawley rats were randomly assigned to either spongialization, radiofrequency ablation or an untreated control group. Rats were killed after 1 or 7 weeks for histological evaluation or after 7 weeks for biomechanical testing. RESULTS: Histological evaluation showed better tissue organization in the control and spongialization group compared to the radiofrequency ablation group. The highest collagen I to collagen III quotient was found in the control group, followed closely by the spongialization group. Measured quotients showed a decrease in the values after 1 week compared to the values after 7 weeks, except in the radiofrequency ablation group, where an increase was detected. A significant difference was found in the load to failure test comparing the radiofrequency ablation group to the spongialization group (p = 0.0409) and control group (p = 0.014), but not comparing the spongialization group to the control group (p = 0.2456). CONCLUSIONS: The results of this study suggest that spongialization of the footprint before attaching the torn supraspinatus tendon can lead to better structural properties and higher quality of tendon-to-bone restoration at the insertion area when compared with radiofrequency ablation.