SLAP Lesions in the Overhead Athlete

[Research progress on the relationship between shoulder instability and superior labrum anterior posterior lesion]

OBJECTIVE

To summarize the relationship between shoulder instability and superior labrum anterior posterior (SLAP) lesion.

METHODS

The characteristics of shoulder instability and SLAP lesion were analyzed, and the relationship between them in pathogenesis, clinical symptoms, and biomechanics was discussed by referring to relevant domestic and foreign literature.

RESULTS

Shoulder instability and SLAP lesion can occur both spontaneously and respectively. SLAP lesion destroys the superior labrum integrity and the long head of biceps tendon (LHBT) insertion, causing excessive humeral head displacement against glenoid, and leading to shoulder instability. While chronic repetitive or acute high-energy traumatic shoulder instability can in turn aggravate SLAP lesion, resulting in expansion and increased degree of the original lesion.

CONCLUSION

SLAP lesion destroys mechanisms of shoulder stability, while shoulder instability causes tears of the upper labrum and the LHBT, showing a connection between shoulder instability and SLAP lesion. However, the existing evidence can only demonstrate that shoulder instability and SLAP lesion induce and promote the development of each other, instead of a necessary and sufficient condition. Therefore, the specific causal relationship between the two remains unknown and needs to be further studied.

Establishing and comparing reference preoperative Patient-Reported Outcomes Measurement Information System (PROMIS) scores in patients undergoing shoulder surgery

BACKGROUND

The Patient-Reported Outcomes Measurement Information System (PROMIS) has become increasingly popular among orthopedic surgeons treating shoulder pathology. Despite this, there have been few studies that have described and compared preoperative reference scores for specific shoulder surgical procedures. The primary purpose of this study was to establish and compare baseline preoperative PROMIS scores for 3 common types of shoulder surgery: rotator cuff repair (RCR), total shoulder arthroplasty (TSA), and labral repair (LR). The secondary goal was to stratify these operative groups by diagnosis and compare preoperative PROMIS scores.

METHODS

In this cross-sectional study, adult and pediatric patients who underwent surgery for either RCR, TSA, or LR were included. PROMIS-Upper Extremity (UE), PROMIS-Pain Interference (PI), and PROMIS-Depression (D) scores that were collected at each patient's preoperative visit were reviewed. Continuous and categorical variables were compared between operative groups using analysis of variance and χ² or Fisher exact tests, respectively. Multivariable general linear models were used to identify significant independent predictors of PROMIS scores when controlling for age, sex, and body mass index.

RESULTS

A total of 413 patients were included in the study: 272 in the RCR group, 84 in the TSA group, and 57 in the LR group. The average PROMIS-UE score was 39.8 in the LR group vs. 29.9 in the RCR group (P < .001) and 29.6 in the TSA group (P < .001). There was no difference between the mean RCR and TSA PROMIS-UE scores (P = .93). The average PROMIS-PI score was 56.6 in the LR group vs. 62.8 in the RCR group (P < .001) and 63.9 in the TSA group (P < .001). There was no difference between RCR and TSA PROMIS-PI scores (P = .09). The average PROMIS-D score was 43.5 in the LR group vs. 47.7 in the RCR group (P = .004) and 50.3 in the TSA group (P < .001). The TSA group had a higher mean PROMIS-D score than the RCR group (P = .03). For PROMIS-UE scores, age and body mass index were not found to be significant independent predictors (P = .98 and P = .88, respectively). For PROMIS-PI scores, age, body mass index, and sex were not found to be significant independent predictors (P = .31, P = .81, and P = .48, respectively).

CONCLUSION

Patients undergoing shoulder LR had higher preoperative function scores and lower pain interference and depression scores than those undergoing TSA and RCR. These baseline PROMIS scores should be taken into consideration when tracking a patient's outcomes after surgery, as a certain score could mean drastically different functional and pain outcomes depending on the underlying pathology.

Diagnostic performance of 3D-multi-Echo-data-image-combination (MEDIC) for evaluating SLAP lesions of the shoulder

Background

Superior labral anterior to posterior (SLAP) lesions remain a clinical and diagnostic challenge in routine (non-arthrographic) MR examinations of the shoulder. This study prospectively evaluated the ability of 3D-Multi-Echo-Data-Image-Combination (MEDIC) compared to that of routine high resolution 2D-proton-density weighted fat-saturated (PD fs) sequence using 3 T-MRI to detect SLAP lesions using arthroscopy as gold standard.

Methods

Seventeen consecutive patients (mean age, 51.6 ± 14.8 years, 11 males) with shoulder pain underwent 3 T MRI including 3D-MEDIC and 2D-PD fs followed by arthroscopy. The presence or absence of SLAP lesions was evaluated using both sequences by two independent raters with 4 and 14 years of experience in musculoskeletal MRI, respectively. During arthroscopy, SLAP lesions were classified according to Snyder’s criteria by two certified orthopedic shoulder surgeons. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 3D-MEDIC and 2D-PD fs for detection of SLAP lesions were calculated with reference to arthroscopy as a gold standard. Interreader agreement and sequence correlation were analyzed using Cohen’s kappa coefficient.

Figure 1 demonstrates the excellent visibility of a proven SLAP lesion using the 3D-MEDIC and Fig. 2 demonstrates a false-positive case.

Results

Arthroscopy revealed SLAP lesions in 11/17 patients. Using 3D-MEDIC, SLAP lesions were diagnosed in 14/17 patients by reader 1 and in 13/17 patients by reader 2. Using 2D-PD fs, SLAP lesions were diagnosed in 11/17 patients by reader 1 and 12/17 patients for reader 2. Sensitivity, specificity, PPV, and NPV of 3D-MEDIC were 100.0, 50.0, 78.6, and 100.0% for reader 1; and 100.0, 66.7, 84.6, and 100% for reader 2, respectively. Sensitivity, specificity, PPV, and NPV of 2D-PD fs were 90.9, 83.3, 90.9, and 83.3% for reader 1 and 100.0, 83.3, 91.7, and 100.0% for reader 2. The combination of 2D-PD fs and 3D-MEDIC increased specificity from 50.0 to 83.3% for reader 1 and from 66.7 to 100.0% for reader 2. Interreader agreement was almost perfect with a Cohen’s kappa of 0.82 for 3D-MEDIC and 0.87 for PD fs.

Conclusions

With its high sensitivity and NPV, 3D-MEDIC is a valuable tool for the evaluation of SLAP lesions. As the combination with routine 2D-PD fs further increases specificity, we recommend incorporation of 3D-MEDIC as an additional sequence in conventional shoulder protocols in patients with non-specific shoulder pain.