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Subcoracoid impingement after ossification of the subscapularis tendon
Subcoracoid
impingement
subscapularis Luis Peidro,
after ossification
of the
tendon
PhD, Adrib
Serra,
MD,
and Santiago
Suso, PhD, Barcelona,
Spain
c ‘.
alclflc tendinitis of the shoulder is a common process with an unknown cause. However, the presence of ossified tissue is rare in this location .3 We present a case of ossification of the subscapularis tendon that was accompanied by simultaneous subcoracoid and subacromial impingement symptoms. CASE
REPORT
A 52-year-old man who lifted heavy objects as a manual worker was referred to our orthopaedic service with a 5year history of pain and tenderness in his right shoulder. He had been dia nosed by others as having chronic calcific tendinitis o 7 the rotator cuff and was treated unsuccessfully with nonsteroidal antiinflamatory drugs, physiotherapy, and repeated subacromial corticoanesthetic injections. He denied having a previous shoulder iniur . Physical examination revealed painful active shou Yder motion; forward elevation and internal rotation were especially painful. The anterior impingement signs were positive. The “lift-off” sign indicated weakness of the subscapularis and the impingement test achieved only partial pain relief. Radiographs showed the presence of some calcified bodies in front of the lesser tuberosity (Figures 1 and 2). A subcoracoid local anesthetic injection was performed and complete pain relief was obtained. Arthrography and computed tomography scans revealed that calcified bodies with an osseous structure were located within the subscapularis tendon (Figure 3). A rotator cuff tear was not visualized. The hematologic and biochemical laboratory test results were within normal limits. Surgery was performed with a limited deltopectoral approach prolonged to the acromion. We found 4 ossified bodies of different size within the subscapularis tendon, the largest of which measured 2 x 1.5 x 0.6 cm. The bodies were removed and the resultant defect was closed with nonabsorbable sutures. Anterior acromioplasty was also performed. A rehabilitation program was initiated early. Pathologic examination of the calcified bodies showed mature osseous tissue with bony trabeculae of different thicknesses (Figure 4). At 2-years of follow-up, a good result was shown to have been obtained. There was only slight shoulder pain From the Department of Barcelona.
of Orthopaedics,
Hospital
Clinic,
Reprint requests: Luis Peidro, PhD, Cirugia Ortopbdica tologia, Hospital Clinic, c/ Villarroel 170, 08036 Spain. J Shoulder
Elbow
Copyright Board
0
1058-2746/99/$8.00
170
Surg
1999 of Trustees.
1999;8:
by Journal + 0
University y TraumaBarcelona,
170-I. of Shoulder 32/4/91073
and
Elbow
Surgery
Figure lesser
1 Anteroposterior tuberosity.
Figure
radiograph.
2 Axillar
Note
ossification
in front
of
radiograph.
and minimal internal rotation deficiency, though the scapularis muscle continued to have residual weakness.
sub-
DISCUSSION Subcoracoid impingement of the rotator cuff between the humeral head and the coracoid process produces pain in the front ortion of the shoulder that is most intense during forwar cr flexion and internal rotation.2J Subcoracoid
J Shoulder Volume
f/bow 8, Number
Peidro,
Surg
Serra,
and
Suso
171
2
Figure 3 Computed tomography scapuloris tendon between coracoid
scan. Note ossification in subprocess and lesser tuberosity.
impingement may be caused by either a decrease in the subcoracoid space or an increase in its contents of that space. Other possible mechanisms are trauma such as fracture of the coracoid process or the lesser tuberosity, iatrogenia after bone block procedures for anterior instability of the sho u Id er, f uric t’ ronal disability as a result of laxity or tear of the subscapularis with or without dislocation of the long head of the biceps, and calcification of the subscapularis.2I4 Clinical findings, with positive impingement signs and weakness of the subscapularis tendon, and pain relief obtained by anesthetic injection at the subacromial and subcoracoid space, led us to suspect the simultaneous presence of chronic impingement syndrome and subcoracoid impingement. However, computed tomography scans did not show a decrease of the average humerocoracoid space, probably because the scans were not performed with the upper limb internally rotated. To treat both suspected pathologic conditions, anterior acromioplasty and removal of the ossifications were performed. Many complex changes, both cellular and molecular, can be observed in calcific tendinitis, but conclusive evidence of a single mechanism inherent in these changes has not been established. The causative mechanism of tendon calcification remains unknown.’ Uhthoffs has suggested that bone forms in calcific tendinitis as a result of renewed blood supply to a previously calcified tendon and reports having found 2 cases of ossifying tendons. Uhthoff et al6 report that decreased tissue hypoxia may lead to the trans-
Figure mature
4 Histologic osseous tissue
image of subscapularis with well-formed bone
ossification. trabeculae.
Note
formation of tendon into fibrocartilage in which chondrocytes mediate the deposition of calcium and the development of a bony mass. However, the presence of ossified tissue in patients with calcific tendinitis is very unusual, so little can be deduced about the pathologic mechanisms. Other explanations for an ossified tendon could be the presence of a sesamoid bone, an ossified tendon tear, or traumatic sequelae. These possibilities were excluded in this case because there was no histor of previous trauma or tendon tear. The presence of ossi Yied tissue should be considered in the examination of patients with chronic calcific tendinitis.
REFERENCES Archer RS, Bayley JIL, Archer CW, All SY Cell and matrix changes associated wrth pathologrcal calcrficatron of the human rotator cuff tendons J Anat 1993,182 l-1 2 Gerber C, Terrrer F, Ganz R The role of the coracord orocess rn the chronic rmprngement syndrome J Bone Joint Surg’ 1985, 676 703-8 Ozakr J, Kugar A, Tomrta Y, Tamar S Tear of an ossrfred rotator cuff of the shoulder Acta Orthop Stand 1992,63 339-40 Patte D 254.55-9
The
subcoracord
rmpmgement
Clm
Orthop
Uhthoff HK Calcibrng tendrnrtrs, an active cell-mediated ficatron Virchows Archrv A, Pathologrcal Anatomy Hrstopathology 1975,366,5 l-8 Uhthoff concept
1990, calcrand
HK, Sarkar K, Maynard HA Calcrfyrng tendrnrtrs a new of rts pathogenesrs Clin Orthop 1976; 1 18 154-7
impingement
subscapularis Luis Peidro,
after ossification
of the
tendon
PhD, Adrib
Serra,
MD,
and Santiago
Suso, PhD, Barcelona,
Spain
c ‘.
alclflc tendinitis of the shoulder is a common process with an unknown cause. However, the presence of ossified tissue is rare in this location .3 We present a case of ossification of the subscapularis tendon that was accompanied by simultaneous subcoracoid and subacromial impingement symptoms. CASE
REPORT
A 52-year-old man who lifted heavy objects as a manual worker was referred to our orthopaedic service with a 5year history of pain and tenderness in his right shoulder. He had been dia nosed by others as having chronic calcific tendinitis o 7 the rotator cuff and was treated unsuccessfully with nonsteroidal antiinflamatory drugs, physiotherapy, and repeated subacromial corticoanesthetic injections. He denied having a previous shoulder iniur . Physical examination revealed painful active shou Yder motion; forward elevation and internal rotation were especially painful. The anterior impingement signs were positive. The “lift-off” sign indicated weakness of the subscapularis and the impingement test achieved only partial pain relief. Radiographs showed the presence of some calcified bodies in front of the lesser tuberosity (Figures 1 and 2). A subcoracoid local anesthetic injection was performed and complete pain relief was obtained. Arthrography and computed tomography scans revealed that calcified bodies with an osseous structure were located within the subscapularis tendon (Figure 3). A rotator cuff tear was not visualized. The hematologic and biochemical laboratory test results were within normal limits. Surgery was performed with a limited deltopectoral approach prolonged to the acromion. We found 4 ossified bodies of different size within the subscapularis tendon, the largest of which measured 2 x 1.5 x 0.6 cm. The bodies were removed and the resultant defect was closed with nonabsorbable sutures. Anterior acromioplasty was also performed. A rehabilitation program was initiated early. Pathologic examination of the calcified bodies showed mature osseous tissue with bony trabeculae of different thicknesses (Figure 4). At 2-years of follow-up, a good result was shown to have been obtained. There was only slight shoulder pain From the Department of Barcelona.
of Orthopaedics,
Hospital
Clinic,
Reprint requests: Luis Peidro, PhD, Cirugia Ortopbdica tologia, Hospital Clinic, c/ Villarroel 170, 08036 Spain. J Shoulder
Elbow
Copyright Board
0
1058-2746/99/$8.00
170
Surg
1999 of Trustees.
1999;8:
by Journal + 0
University y TraumaBarcelona,
170-I. of Shoulder 32/4/91073
and
Elbow
Surgery
Figure lesser
1 Anteroposterior tuberosity.
Figure
radiograph.
2 Axillar
Note
ossification
in front
of
radiograph.
and minimal internal rotation deficiency, though the scapularis muscle continued to have residual weakness.
sub-
DISCUSSION Subcoracoid impingement of the rotator cuff between the humeral head and the coracoid process produces pain in the front ortion of the shoulder that is most intense during forwar cr flexion and internal rotation.2J Subcoracoid
J Shoulder Volume
f/bow 8, Number
Peidro,
Surg
Serra,
and
Suso
171
2
Figure 3 Computed tomography scapuloris tendon between coracoid
scan. Note ossification in subprocess and lesser tuberosity.
impingement may be caused by either a decrease in the subcoracoid space or an increase in its contents of that space. Other possible mechanisms are trauma such as fracture of the coracoid process or the lesser tuberosity, iatrogenia after bone block procedures for anterior instability of the sho u Id er, f uric t’ ronal disability as a result of laxity or tear of the subscapularis with or without dislocation of the long head of the biceps, and calcification of the subscapularis.2I4 Clinical findings, with positive impingement signs and weakness of the subscapularis tendon, and pain relief obtained by anesthetic injection at the subacromial and subcoracoid space, led us to suspect the simultaneous presence of chronic impingement syndrome and subcoracoid impingement. However, computed tomography scans did not show a decrease of the average humerocoracoid space, probably because the scans were not performed with the upper limb internally rotated. To treat both suspected pathologic conditions, anterior acromioplasty and removal of the ossifications were performed. Many complex changes, both cellular and molecular, can be observed in calcific tendinitis, but conclusive evidence of a single mechanism inherent in these changes has not been established. The causative mechanism of tendon calcification remains unknown.’ Uhthoffs has suggested that bone forms in calcific tendinitis as a result of renewed blood supply to a previously calcified tendon and reports having found 2 cases of ossifying tendons. Uhthoff et al6 report that decreased tissue hypoxia may lead to the trans-
Figure mature
4 Histologic osseous tissue
image of subscapularis with well-formed bone
ossification. trabeculae.
Note
formation of tendon into fibrocartilage in which chondrocytes mediate the deposition of calcium and the development of a bony mass. However, the presence of ossified tissue in patients with calcific tendinitis is very unusual, so little can be deduced about the pathologic mechanisms. Other explanations for an ossified tendon could be the presence of a sesamoid bone, an ossified tendon tear, or traumatic sequelae. These possibilities were excluded in this case because there was no histor of previous trauma or tendon tear. The presence of ossi Yied tissue should be considered in the examination of patients with chronic calcific tendinitis.
REFERENCES Archer RS, Bayley JIL, Archer CW, All SY Cell and matrix changes associated wrth pathologrcal calcrficatron of the human rotator cuff tendons J Anat 1993,182 l-1 2 Gerber C, Terrrer F, Ganz R The role of the coracord orocess rn the chronic rmprngement syndrome J Bone Joint Surg’ 1985, 676 703-8 Ozakr J, Kugar A, Tomrta Y, Tamar S Tear of an ossrfred rotator cuff of the shoulder Acta Orthop Stand 1992,63 339-40 Patte D 254.55-9
The
subcoracord
rmpmgement
Clm
Orthop
Uhthoff HK Calcibrng tendrnrtrs, an active cell-mediated ficatron Virchows Archrv A, Pathologrcal Anatomy Hrstopathology 1975,366,5 l-8 Uhthoff concept
1990, calcrand
HK, Sarkar K, Maynard HA Calcrfyrng tendrnrtrs a new of rts pathogenesrs Clin Orthop 1976; 1 18 154-7