Circumferential Lesions of the Glenoid Labrum
Condition: Shoulder Instability
Study type: Observational

Summary: 
      Objective: Symptomatic pan-labral or circumferential (360 degree) tears of the glenohumeral
      labrum are an uncommon injury. The purpose of this study is to report the prospective
      surgical results of circumferential lesions of the glenoid labrum using validated outcome
      instruments.

      Methods: From July 2003 to May 2006, 41 shoulders in 39 patients with mean age of 25.1 years
      (range, 17 to 38) were prospectively enrolled in a multi-center study (3 surgeons) and
      treated for a circumferential (360-degree) lesion of the glenoid labrum. There were 34 men
      and 5 women, all with a primary diagnosis of pain and recurrent shoulder instability. All
      patients underwent arthroscopic repair of the circumferential labral tear with a mean of 7.1
      suture anchors (range, 6 to 9). The outcomes in 39 of 41 shoulders (92.7% follow-up) were
      assessed at a mean final follow-up of 31.8 months (range, 24 to 53 months) with VAS pain and
      instability scales (0 to 10), a physical examination, the Single Assessment Numeric
      Evaluation Score (SANE), the American Shoulder and Elbow Surgeons Score (ASES), and the SF-12
      score.
    

Detailed description: 
      Patient Demographics A total of 41 shoulders (34 men, 5 women) with mean age of 25.1 years
      (range, 17 to 38 years) were prospectively enrolled. The outcomes in 39 of 41 shoulders
      (92.7% follow-up) were assessed at a mean final follow-up of 31.8 months (range, 24 to 53
      months). Thirty-seven of 39 patients were right handed. The dominant shoulder was affected in
      30 shoulders, non-dominant in 11. Every patient had a primary chief complaint of shoulder
      pain with a history of anterior and/or posterior shoulder instability. All had a traumatic
      onset of their symptoms, twelve as a result of contact sports and had failed initial
      non-operative management. Two patients had had a previous operation, including one patient
      with a previous open Bankart, 4 years prior to index operation, and another that had a
      previous posterior arthroscopic "labral repair" which subsequently sustained an anterior
      dislocation. This was revised with open inferior capsular shift, 2 years prior to index
      operation. Twenty-six shoulders presented with clear evidence of primary anterior
      instability. These patients clearly remembered the initial dislocation event and
      demonstrating an abducted-externally rotated arm at the time of dislocation. Twenty-four of
      these patients also had pre-reduction radiographs showing anterior dislocation. An additional
      five patients in the group had variable levels of glenoid bone loss (5-10%), with small
      Hill-Sachs injuries. Nine shoulders had clear evidence of posterior instability as evidenced
      by these patients clearly remembering their initial dislocation event, and demonstrating a
      forward flexed, adducted, and internally rotated position of the arm at the time of
      dislocation. The remaining six shoulders could not discern between anterior or posterior
      instability as a primary direction.

      All physical examinations were performed by the treating orthopedic surgeon. All shoulders
      were compared to the contralateral side for range of motion, strength, tenderness, and
      provocative maneuvers. Range of motion was examined in forward flexion, abduction, and
      external and internal rotation at 00 and 90 0 of abduction. As part of our normal protocol,
      values not significantly different from the contralateral side were recorded as "normal". Any
      value noted to be abnormal was to be recorded in degrees, or in the case of internal rotation
      at 00, the spinal level. On physical examination no patient was noted to have a significant
      loss of active or passive motion in flexion, abduction, internal rotation, or external
      rotation at 00. Thirty-nine of the 41 shoulders demonstrated a positive apprehension sign20,
      and thus arms were not taken to maximum external rotation in the abducted position in these
      patients. Strength testing was accomplished with manual muscle testing compared to the
      opposite arm in all 39 patients. Specific testing included shoulder abduction, internal and
      external rotation at 00, resisted scaption, lift-off and belly press testing20, as well as
      elbow flexion and extension, wrist flexion and extension, and interosseous muscle testing. No
      significant deficit was noted in any of these positions. All patients had pain induced
      limitation of strength testing during an active compression test20. Provocative maneuvers
      included anterior and posterior load and shift testing, an anterior apprehension test, a
      push-pull test for posterior instability, and an active compression test20 . Thirty-nine of
      41 shoulders had a positive apprehension test20. Care was taken to place the patient with
      their arm in 90 degrees of abduction and increasing external rotation. Patients were asked to
      discern when they became symptomatic, and then asked whether the shoulder felt like it was
      "coming out" or if their symptoms were just pain. A positive apprehension test was defined as
      a sensation of the former. All 39 patients had a positive push-pull test for posterior laxity
      20and pain. This test is performed by placing the patient supine on the examining table with
      the arm placed in 90 degrees of abduction and neutral rotation. The wrist is grasped and
      "pulled" by the examiner with one hand, while the other hand is used to "push" the shoulder
      backward. A positive test is signified by subluxation of the joint with a reproduction of the
      patient's symptoms. Impingement signs including Neer's sign, Hawkin's sign, and painful arc
      were performed on all 39 patients 20. At least one of the signs was positive in all patients.
      An active compression test was performed on all 39 patients, and noted to be positive with
      pain and weakness in all patients. No patient demonstrated an increased sulcus sign, or any
      sign of hyperlaxity.

      MRIs were obtained in all 41 shoulders and all radiologic reports were reviewed. Thirty of 41
      of these MRI's were done in conjunction with a gadolinium contrast arthrogram.
      Intraoperatively, all patients underwent an examination under anesthesia with particular
      attention directed toward anterior and posterior laxity examinations compared to the opposite
      side according to the grading system for instability established by the American Shoulder and
      Elbow Surgeons 21,22. Inferior laxity was measured by a sulcus sign measured in centimeters
      from the edge of the acromion to the top of the humeral head. At arthroscopy, all patients
      demonstrated complete circumferential tear of the glenoid labrum. One patient had an
      additional complete radial split of the labrum at the 1 o'clock position (anteriorly), which
      was repaired. The average patient had 7.1 anchors placed (range, 6-9). Post-operative
      examination while still under anesthesia showed restoration of normal anterior and posterior
      glenohumeral translation "to the rim".

      Post-operatively, patients were seen at 2 weeks, 6 weeks, and 3 months, 6 months, one year,
      and yearly after that. History was taken with particular attention to recurrence of
      dislocation or feelings of apprehension or pain. Physical examination beginning at 3 months
      assessed range of motion, anterior apprehension, and posterior reproduction of symptoms using
      a push-pull test20. In addition, strength testing was accomplished, as was an active
      compression test. Patient outcomes were re-accomplished for the SANE, modified ASES and SF-12
      visits at each follow-up visit beginning at 6 weeks. In addition, each patient was asked if
      he or she would undergo the surgery again. All surveys were administered using a standard
      form, and entered into the SOMOS database. Data was combined among surgeons using
      de-identified patient data.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Department of Defense active duty members
      
Keywords: shoulder instability; labral lesions; arthroscopic labral repair; SLAP; triple labrum; circumferential labrum; Pan-labral lesion