Reproducibility and reliability of the Snyder classification of superior labral anterior posterior lesions among shoulder surgeons

BACKGROUND

Previous studies of the reliability of classifications for superior labral anterior and posterior (SLAP) lesions suggest that intraobserver/interobserver reliability is poor.

PURPOSE

The goals were to (1) evaluate intraobserver/interobserver reliability of the Snyder classification of labrum tears among experienced surgeons, (2) determine the effect of simplifying that classification into normal versus abnormal labrums, (3) determine the reliability of subdividing type II SLAP lesions, and (4) evaluate the effect of videotape quality on diagnostic confidence.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 3.

METHODS

At 2 separate times, 5 experienced shoulder surgeons (all >10 years of practice) evaluated 90 videotapes of shoulder arthroscopy performed for SLAP lesions to identify lesion type, to grade video quality, and to determine degree of confidence in diagnosis. The results were compared for intraobserver reliability (κ analysis) and interobserver reliability (intraclass correlation coefficients) and effect of video quality on diagnostic confidence. Significance was set at P < .05.

RESULTS

When the choices were normal labrum or the 4 types of SLAP lesions, the intraobserver agreements (mean κ, 0.670) and interobserver agreements (mean correlation, 0.804) were substantial. When the labrums were divided into normal (normal and type I) and abnormal (types II-IV), the intraobserver agreements (mean κ, 0.792) and interobserver agreements (mean correlation, 0.648) were substantial. When the 3 type II SLAP lesion subvariants were evaluated, the intraobserver agreement (mean κ, 0.598) was moderate, and the interobserver agreement (mean correlation, 0.804) was substantial. The confidence of the diagnosis was highly correlated with the perceived video quality (average Pearson correlation, 0.718; P < .01). Repeated measures analysis showed a significant relationship between confidence and quality (parameter estimate, 0.732; standard error, 0.021; P < .01) adjusting for rater and review.

CONCLUSION

For experienced shoulder surgeons, the Snyder classification is a reliable system for identifying SLAP lesions.

Subscapularis strain from swinging a baseball bat in an adolescent with closed physis

A healthy 16-year-old female baseball player was referred by her pediatrician for evaluation of pain in her right, dominant shoulder. The pain had begun insidiously 4 weeks previously after several sessions of batting practice and had worsened until she could not participate in baseball, even with low doses of ibuprofen. She was not participating in any other sports or weight lifting and had had no previous incidents of shoulder pain, but she did have a history of being able to voluntarily subluxate the right shoulder since she was a child. Her voluntary shoulder subluxation and reduction did not reproduce or worsen her pain. Results from her physical examination and radiographs were normal. Magnetic resonance imaging showed edema in the subscapularis muscle consistent with acute muscle strain. She was treated with 6 weeks of rest, ice, and anti-inflammatory medication as needed. She returned to baseball and hitting during the following 6 weeks with no limitations.

Does a positive neer impingement sign reflect rotator cuff contact with the acromion?

BACKGROUND

One possible cause of shoulder pain is rotator cuff contact with the superior glenoid (cuff-glenoid contact) with the arm in flexion, as occurs during a Neer impingement sign. It has been assumed that the pain with a Neer impingement sign on physical examination of the shoulder was secondary to the rotator cuff making contact with the anterior and lateral acromion.

QUESTIONS/PURPOSES

We determined if the arm position where pain occurs with a Neer impingement sign would correlate with the position where the rotator cuff made contact with the superior glenoid, as determined by arthroscopic evaluation.

PATIENTS AND METHODS

We prospectively studied 398 consecutive patients with a positive Neer impingement sign during office examination and used a handheld goniometer to measure (in degrees of flexion) the arm position in which impingement pain occurred. During subsequent arthroscopy, the arm was moved into a similar position, and we measured the arm's position in flexion at the point the rotator cuff made contact with the superior glenoid using a handheld goniometer. We compared the degrees of flexion at which pain occurred preoperatively and at which there was cuff-glenoid contact.

RESULTS

Among the 398 patients, 302 (76%) had arthroscopically documented cuff-glenoid contact, whereas 96 did not. For the 302 patients with a positive Neer sign preoperatively and with arthroscopically documented cuff-glenoid contact, the average preoperative impingement pain position was 120.1°±26.7°, similar to that of the average intraoperative cuff-glenoid contact position of 120.6°±14.7°.

CONCLUSIONS

Our data suggest pain associated with a positive Neer sign more often relates to contact of the rotator cuff with the superior glenoid than to contact between the rotator cuff and acromion.

LEVEL OF EVIDENCE

Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

Triceps tendons: a biomechanical comparison of intact and repaired strength

HYPOTHESIS

Our hypothesis was that the autograft-augmented direct repair of torn triceps tendons would have strength superior than that of direct repair when compared to the strength of intact distal triceps tendons.

MATERIALS AND METHODS

The strength of the intact distal triceps tendon in 8 unpaired, fresh frozen cadaver specimens was measured to tendon failure by uniaxial tension in the sagittal plane. The torn triceps tendons were then repaired by direct repair (sutures through drill holes) or an autograft-augmented direct repair. Each tendon repair was biomechanically tested to failure, and load to displacement curves and the site of tendon failure were recorded. Tendon strength after each repair was compared with that of the other repair technique and with that of the intact triceps tendon. Significance was set at P < .05.

RESULTS

Average failure loads for intact, direct repair, and augmented repair tendons were 1741, 317, and 593 N, respectively; augmented repairs were significantly stronger than direct repairs. In the intact tendon, failure occurred at the insertion site through a tear at the bone tendon interface or through a small cortical avulsion. In the repaired tendons, all but 1 failure occurred through the suture; 1 augmented repair failed first at the tendon and then through the suture.

DISCUSSION

There is a paucity of clinical data regarding the optimal repair for distal triceps avulsion. We found that triceps repair affords less strength than the intact tendon, but augmented repair was nearly twice as strong as that of direct repair. Augmented repair may allow earlier range of motion, weightbearing, and rehabilitation, theoretically decreasing complications associated with the procedure.

CONCLUSIONS

Augmented triceps repair is superior to direct triceps repair for a distal triceps avulsion produced in a cadaver model.

Techniques for suture anchor removal in shoulder surgery

Although suture anchor complications after arthroscopic shoulder surgery are uncommon, they can be devastating, such as articular cartilage or bone loss secondary to a dislodged or prominent suture anchor. Proper insertion of the anchor is the most important factor in the prevention of this complication, but if a complication occurs, prompt recognition and treatment are important to prevent damage to the shoulder. The goals were to (1) discuss strategies for preventing or dealing with dislodged or prominent suture anchors and (2) introduce techniques for removal of these implants.

Arthroscopic fixation technique for comminuted, displaced greater tuberosity fracture

PURPOSE

The purpose of this retrospective study was to evaluate the early results of arthroscopic treatment in patients with comminuted, displaced greater tuberosity (GT) fractures using the arthroscopic double-row suture anchor fixation (ADSF) technique.

METHODS

Between August 2004 and December 2007, we used the ADSF technique in 16 cases of isolated comminuted, displaced GT fractures. The early clinical results were evaluated in these patients at a mean of 24 months (range, 16 to 51 months) after surgery. There were 11 male and 5 female patients with a mean age of 56.5 years (range, 27 to 82 years). These 16 cases had at least 5 mm of displacement of the fracture fragments in any plane. For measurement of clinical outcomes, we assessed range of motion and evaluated the visual analog scale score; the University of California, Los Angeles (UCLA) rating scale; and the shoulder index of the American Shoulder and Elbow Surgeons.

RESULTS

At final follow-up, the visual analog scale score improved from 9.4 (range, 8 to 10 points) to 1.2 (range, 0 to 4 points), the mean UCLA score improved to 31 points (range, 21 to 35 points) postoperatively, and the American Shoulder and Elbow Surgeons score improved to 88.1 points (range, 81.5 to 100 points). According to the UCLA score, there were 3 excellent results, 11 good results, and 2 poor results. Mean forward flexion was 148.7 degrees (range, 120 degrees to 170 degrees), mean abduction was 145 degrees (range, 120 degrees to 170 degrees), mean external rotation in the neutral position was 24 degrees (range, 10 degrees to 40 degrees), and internal rotation improved to the first lumbar vertebral level (from L3 to T7) at last follow-up.

CONCLUSIONS

The early results of the ADSF technique used for displaced, comminuted GT fractures are encouraging, and arthroscopists should attempt to expand the indications for arthroscopic treatment of these fractures.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Clinical and diagnostic tests for shoulder disorders: a critical review

The shoulder is one of the most complex joints in the human body and, as such, presents an evaluation and diagnostic challenge. The first steps in its evaluation are obtaining an accurate history and physical examination and evaluating conventional radiography. The use of other imaging modalities (eg, ultrasound, magnetic resonance imaging and computed tomography) should be based on the type of additional information needed. The goals of this study were to review the current limitations of evidence-based medicine with regard to shoulder examination and to assess the rationale for and against the use of diagnostic physical examination tests.

Clinical and imaging assessment for superior labrum anterior and posterior lesions

In the evaluation of the painful shoulder, especially in the overhead athlete, diagnosing superior labrum anterior and posterior (SLAP) lesions continues to challenge the clinician because of 1) the lack of specificity of examination tests for SLAP; 2) a paucity of well-controlled studies of those tests; and 3) the presence of coexisting confounding abnormalities. Some evidence indicates that multiple positive tests increase the likelihood that a SLAP lesion is present, but no one physical examination finding conclusively makes that diagnosis. The goals of this article were to review the physical examination techniques for making the diagnosis of SLAP lesions, to evaluate the clinical usefulness of those examinations, and to review the role of magnetic resonance imaging in making the diagnosis.

An analysis of shoulder laxity in patients undergoing shoulder surgery

BACKGROUND

It has been recognized that there is a distinction between shoulder laxity and shoulder instability and that there is a wide range of normal shoulder laxities. Our goals were (1) to evaluate if the ability to subluxate the shoulder over the glenoid rim in patients under anesthesia would be more prevalent than the inability to do so, (2) to determine if patients with a diagnosis of instability would have significantly more shoulder laxity in the operatively treated shoulder than in the contralateral shoulder, and (3) to evaluate the observation that higher grades of shoulder laxity would be related to a diagnosis of shoulder instability. We hypothesized that, on examination with the patient under anesthesia, most shoulders could be subluxated over the glenoid rim and that the degree of shoulder laxity would be related to diagnosis.

METHODS

In the present study of 1206 patients undergoing shoulder surgery, we evaluated the symptomatic and contralateral shoulders with use of a modified anterior and posterior drawer test and a sulcus sign test, with the patients under anesthesia. The anterior and posterior translations were graded as no subluxation (Grade I), subluxation over the glenoid rim with spontaneous reduction (Grade II), or subluxation without spontaneous reduction (Grade III). The sulcus sign was graded as <1.0 cm (Grade I), 1.0 to 2.0 cm (Grade II), or >2.0 cm (Grade III).

RESULTS

When the patients were evaluated while under anesthesia, the humeral head could be subluxated over the rim anteriorly in 81.6% (984 of 1206) of the patients and posteriorly in 57.5% (693 of 1206) of the patients. When the patients were evaluated while under anesthesia, there was an increase in the laxity grade anteriorly, posteriorly, and inferiorly in 50.8%, 36.3%, and 15.8% of the patients, respectively, as compared with the preoperative assessment. For all laxity testing, the higher the grade of laxity in an anterior, posterior, or inferior direction, the greater the chance that the patient had a diagnosis of instability. Compared with Grade-I laxity, Grade-III laxity increased the odds of a diagnosis of instability in the anterior (odds ratio, 170), posterior (odds ratio, 32), and inferior (odds ratio, 10.3) directions. Compared with Grade-I laxity, Grade-II laxity increased the odds of a diagnosis of instability in the anterior (odds ratio, 9.8), posterior (odds ratio, 4.6), and inferior (odds ratio, 4.4) directions.

CONCLUSIONS

The ability to subluxate the humeral head over the glenoid rim in the patient who is undergoing shoulder surgery under anesthesia is common regardless of the diagnosis. Higher grades of shoulder laxity are associated with shoulder instability.

Clinical evaluation of the shoulder shrug sign

The "shrug sign" (inability to lift the arm to 90 degrees abduction without elevating the whole scapula or shoulder girdle) has been associated with a diagnosis of rotator cuff disease. Based on our clinical experience, we hypothesized the shrug sign is not a specific diagnostic sign for this condition, but rather is associated with various shoulder conditions and shoulder weakness and loss of range of motion. We retrospectively reviewed 982 consecutive patients who had been examined preoperatively for the shrug sign. A positive shrug sign was present in 51.3% of the patients, and the average distance lost from the horizontal was 20.5 degrees +/- 2.2 degrees (standard error of mean). Increasing age was associated with the presence of a shrug sign. The highest incidence was in patients with adhesive capsulitis (94.7%). The shrug sign was not sensitive for tendinosis, partial rotator cuff tears, or full-thickness or massive rotator cuff tears. The shrug sign was associated with weakness in abduction, night pain, and loss of range of motion, especially passive abduction. Although the shrug sign is useful as a general sign of shoulder abnormality, particularly when associated with stiffness, it was not specific or sensitive for rotator cuff problems.

LEVEL OF EVIDENCE

Level II, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.