Cuff Arthropathy

Dr. Neer clarified and popularised this topic more than 20 years ago, with the description of “cuff tear arthropathy.”  He initially described two stages, “pre collapse” with upward migration of the humeral head, and true cuff tear arthropathy with collapse of the humeral head [4].  In 1990 Hamada and Fukuda published a new classification of the radiographic stages of massive rotator cuff tear and arthropathy based chiefly on the acromiohumeral distance with five grades.  In grade 1 the acromiohumeral distance (AHD) is greater than 6 mm.  In grade 2 the acromiohumeral distance is 6 mm or less.  In grade 3 acetabulization, defined as a concave deformity of the acromion under the surface, is added to the grade 2 characteristics.  In grade 4 narrowing of the glenohumeral joint is added to the grade 3 features.  In grade 5 humeral head collapse is present which is characteristic of the cuff tear arthropathy [1].  Grades 1, 2 and 3 are not true arthritis as there is no involvement of the glenohumeral joint.  Grades 4 and 5 are true arthropathy.  We feel it is useful to divide grade 4 into two subclasses: grade 4A, glenohumeral joint narrowing without acetabulization, and grade 4B, glenohumeral joint narrowing with acetabulization.  If we want to use Hamada’s classification and discuss operative indications in massive rotator cuff tears and arthritis, we must know that the acromiohumeral distance (AHD) is measured on plain radiographs using A-P view in neutral rotation with double obliquity with the x-ray source placed 1.2 meters from the patient.  Although this technique can be performed without fluoroscopy by a very experienced radiographic technologist, it is much easier and more reproducible to use fluoroscopic control.  Use of fluoroscopic control is more expensive but still less expensive than an MRI.  This radiographic technique, when performed correctly, yields invaluable information about rotator cuff pathology and arthritis.  The AHD has been reported in the literature to be a sensitive indicator for full thickness rotator cuff tears: an AHD of 6 to 7 mm was reported as the lowest limit on normal shoulders by several authors. 

Arthritis and rotator cuff tears seem to occur concomitantly not infrequently with a much higher incidence than classic cuff tear arthropathy.  If we consider articular cartilage degeneration (rather than radiographic changes), Feeney showed in a cadaver study that the articular cartilage degeneration was almost twice as frequent in the group with rotator cuff tears as in those without tears [2].

We recently reported the results of arthroscopic debridement with release of the long head of biceps in the treatment of irreparable rotator cuff tears.  Three hundred seven cases were followed for a mean of 57 months (range 24 to 148).  Females represented 57%, the operative age averaged 64.3 years, older than the classic 54 to 58 year old mean age reported for most series of rotator cuff repair.  One third of patients had a subacromial decompression at the same time.  All patients had pre and postoperative fluoroscopic positioned A-P radiographs with internal, neutral and external rotation allowing for measurement of the AHD and grading by Hamada-Fukuda classification (Table I indicates the preoperative grade of arthritis).

Seventy-four percent of patients had preoperative evaluation of the rotator cuff musculature (either with CT arthrography or MRI) allowing correlations between arthritis and muscular fatty infiltration.  The clinical results have been reported previously [5] and we will focus more on the pre and postoperative radiographic changes observed after this “conservative treatment” of irreparable rotator cuff tears.

Table I shows the progression of degenerative changes, with an average follow-up of 5 years.  No progression occurred in 75% of the cases, 18% progressed one grade, 5% progressed two grades, 1.3% progressed three grades, and 0.7% progressed four grades.

Although preoperatively 54% of our patients had an AHD superior to 6 mm (Hamada grade 1), postoperatively only 40% remained grade 1.  The AHD averaged 6.6 mm preoperatively and 5.3 mm postoperatively (p<0.0001).  We analysed the factors influencing the AHD.  Four factors were statistically highly significant.  The influence of the preoperative delay and the postoperative follow-up (Table II) show that time is important in the development of arthritis.  Preoperatively, despite having an intact long head of biceps, 46% of our patients had superior migration of the humeral head, this percentage increased to 64% postoperatively but we feel that this upward migration is not related to the tenotomy of the long head of biceps because:

We never observed new onset superior migration of the humeral head occurring in the first postoperative year following tenotomy, if we consider the influence of the postoperative follow-up, the difference was statistically significant only when we compared the groups with 2 to 4 years follow-up with the group superior to 6 year follow-up.

The size of the tendinous rupture was not a statistically significant influence; however the specific tendon ruptured was important with rupture of the Infraspinatus statistically related to diminished AHD (Table III).

Fatty infiltration of the Infraspinatus according to Goutallier’s classification was the last significant factor (Table IV) showing that this musculotendinous unit must be considered the main depressor of the humeral head.  When the Infraspinatus muscle was severely fatty infiltrated (grades 3 and 4), the teres minor became an important depressor.  We classified the state of the teres minor as absent, atrophic, normal and hypertrophic and found a statistically significant relationship (p<0.002) with the acromiohumeral distance which was 1 mm, 1.6 mm, 3.2 mm and 3.7 mm respectively.  Acetabulization of the acromion was present in 9.4% of the cases preoperatively and 16.3% postoperatively.  Influencing factors were the number of preoperative corticosteroid injections (p<0.001) which was in actuality probably related more to the preoperative delay (p<0.00001).  Again Infraspinatus tendon ruptures, present in 95% of cases, and severe fatty infiltration (grade 3 and 4), present in 84% of cases, were statistically significant influences (p<0.001).

Glenohumeral joint narrowing (Hamada grade 4) was present in 33% of cases preoperatively and 10% postoperatively.  These patients were not significantly older than the whole series [67 years versus 64 (p=0.01)].  The total progression time, the sum of the preoperative delay and the follow-up, was statistically longer (164 months versus 122 months) in cases without glenohumeral arthritis (p<0.01).  Surprisingly we found a statistical influence of Subscapularis tendon rupture and Subscapularis muscles fatty infiltration (p<0.02) on the onset of glenohumeral arthritis.

Hamada grade 5, characterised by collapse of the humeral head, was present in no cases preoperatively and appeared in 2.3% of cases postoperatively.  These patients were older (72 years old versus 64 years old), had 3 tendon tears, and had a tendency to have Subscapularis fatty infiltration.

CONCLUSION:

It is crucial to define the degree of arthritis and to differentiate cases with and without glenohumeral narrowing.  Superior migration of the humerus is the first stage of arthritis and is strongly correlated with Infraspinatus rupture and fatty infiltration and to a lesser extent to the status of teres minor.  As Hamada described and reported, there is a progression of radiographic changes in massive rotator cuff tear with nonoperative treatment, and this progression increases as the follow-up increases.

Table I: Pre and postoperative glenohumeral osteoarthritis according to Hamada-Fukuda classification

Table II: Influence of pre and postoperative delay on the acromiohumeral distance (AHD)

Table III: Influence of the tendons rupture on the acromiohumeral distance (AHD)

Table IV: Influence of Infraspinatus fatty infiltration on the acromiohumeral distance (AHD)

BIBLIOGRAPHY:

1.                  Hamada K, Fukuda H, Mikasa M, Kobayashi Y.  Roentgenographic findings in massive rotator cuff tears.  A long term observation.  Clin. Orthop. 1990; 254:92-96

2.                  Feeney MS, O’Dowd J, Keay EW, Colville J.  Glenohumeral articular cartilage changes in rotator cuff disease.  J. Shoulder Elbow Surg 2003; 12:20-23

3.                  Fenlin JM, Chase JM, Rushton SA, Frieman BG.  Tuberoplasty: creation of an acromiohumeral articulation.  A treatment option for massive irreparable rotator cuff tears.  J. Shoulder Elbow Surg. 2002;11:136-142

4.                  Neer CS, Craig EV, Fukuda H.  Cuff tear arthropathy.  J. Bone Joint Surg.  Am.  1983;65:1232-1244

5.                  Walch G, Edwards TB, Boulahia A, Szabo I, Nove-Josserand L, Neyton L, Adeleine P.  Arthroscopic tenotomy of the long head of biceps in the treatment of rotator cuff tears.  Clinical and radiological results about 307 cases.  J. Shoulder Elbow Surg. (In Press)