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Teres minor integrity predicts outcome of latissimus dorsi tendon transfer for irreparable rotator cuff tears
Teres minor integrity predicts outcome of latissimus dorsi tendon transfer for irreparable rotator cuff tears John G. Costouros, MD, Norman Espinosa, MD, Marius R. Schmid, MD, and Christian Gerber, MD, Zurich, Switzerland
In patients with irreparable rotator cuff tears, latissimus dorsi tendon transfer (LDTT) can be effective in improving pain and function. However, the results are variable, and the factors that predict good outcomes are poorly understood. The purpose of this study was to investigate whether the integrity of the teres minor musculotendinous unit is predictive of outcome following LDTT. Twenty-two consecutive patients who underwent LDTT for massive, irreparable posterosuperior rotator cuff tears were retrospectively reviewed. Sixteen men and 6 women with a mean age of 58 years (range, 40-68) were analyzed at an average follow-up of 34 months (range, 24-57).Standardized MRI images of all patients were reviewed by 3 independent reviewers. Fatty infiltration of the teres minor was Goutallier stage 0 in 5 patients; stage 1 in 6; stage 2 in 4; stage 3 in 6; and stage 4 in 1. Eleven patients (50%) had partial tears and 2 (9%) had complete tears of the teres minor tendon. Following LDTT, the mean absolute constant score improved from 48 to 62 points ( P ¼ .003), age-adjusted constant score improved from 56% to 72% ( P ¼ .002), and the subjective shoulder value improved from 24% to 68% ( P < .001). Fatty infiltration of the teres minor less than or equal to stage 2 was associated with a better postoperative constant score (67 vs 53, P ¼ .015); age-adjusted constant score (78% vs 59%, P ¼ .012); active external rotation (36 vs 16 , P ¼.016); and active elevation (143 vs 115 , P ¼.012) relative to patients with fatty infiltration greater than stage 2. The presence or absence of a tear of the tendon had no significant effect on outcome. In conclusion, when performing LDTT for massive irreparable posterosuperior rotator cuff tears, fatty infiltration of the teres minor should be considered prior to surgery, as it is predictive of outcome. (J Shoulder Elbow Surg 2007;16:727-734.) From the University of Zurich, Balgrist University Hospital, Zurich, Switzerland. Reprint requests: Christian Gerber, MD, Department of Orthopedics, University of Zurich, Balgrist, Forchstrasse 340, CH-8008 Zurich, Switzerland (E-mail: [email protected]). Copyright ª 2007 by Journal of Shoulder and Elbow Surgery Board of Trustees. 1058-2746/2007/$32.00 doi:10.1016/j.jse.2007.02.128
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rreparable rotator cuff tears are found in a small proportion of patients, as approximately 95% of rotator cuff tears considered for operative treatment are reparable at the time of surgery.7,25While the prevalence of irreparable tendon tears is low, they profoundly affect the functional capacity of patients and can be associated with significant levels of pain and dysfunction.Furthermore, even in the setting of reparable tears, it is becoming clear that fatty infiltration is not reversible and that larger tears with advanced fatty infiltration of the rotator cuff musculature carry a higher risk of failure and are associated with inferior clinical outcomes.5,7,13,14,17 The latissimus dorsi tendon transfer (LDTT) offers a promising solution in the treatment of irreparable tears of the posterosuperior rotator cuff, and has been shown to yield favorable results at mid- to longterm follow-up.1,6,8,9,12,24,26 However, the results have been found to be variable, and the factors which are predictive of good outcome are poorly understood. Although the biomechanical role of the teres minor in rotator cuff function has been studied extensively, it is unclear how it may impact the clinical results of LDTT.15,18,22 The purpose of this study was to investigate whether the structural integrity and degree of fatty infiltration of the teres minor musculotendinous unit prior to surgery is predictive of outcome following LDTT. MATERIALS AND METHODS Twenty-two consecutive patients who underwent LDTT for massive, irreparable posterosuperior rotator cuff tears were retrospectively reviewed clinically and radiographically. Prior to surgery, all patients provided written, informed consent for the procedure. Indications for surgery included moderate to severe pain and subjectively unacceptable dysfunction that was refractory to conservative treatment. Massive, irreparable tears of the supraspinatus and infraspinatus tendons were defined as those with preoperative fatty infiltration greater than stage 2, an acromiohumeral distance of less than 7 ml on a standardized true anteroposterior radiograph, or those which were not surgically reparable at the time of surgery. Conservative treatment consisted of supervised physical therapy and the use of oral nonsteroidal anti-inflammatory medication for a minimum of 6 months. Patients with subscapularis tears; glenohumeral arthritis (Samilson and Prieto Grade > 1);21 static anterior or posterior
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Figure 1 Magnetic resonance image parallel to the glenoid plane through the base of the coracoid. A, The subscapularis, supraspinatus, infraspinatus, and teres minor (arrow) are homogeneous, convex, and voluminous in a normal rotator cuff. B, In a massive posterosuperior tear, the subscapularis is normal, but the supraspinatus and infraspinatus show fatty infiltration and atrophy.In this case, the teres minor (arrow) shows no evidence of fatty infiltration and atrophy.
humeral head subluxation;23 dynamic anterosuperior humeral head subluxation; or excessive superior humeral migration (acromiohumeral distance < 5 mm) were excluded. The study (N ¼ 22) consisted of 16 men and 6 women with a mean age of 58 years (range, 40-68).Surgery was performed on 15 right shoulders and 7 left shoulders, and the dominant arm was involved in 16 cases (73%). Five (23%) were revision surgeries, which consisted of 4 failed open and 1 failed arthroscopic rotator cuff repair. Following surgery, patients were evaluated at regular intervals with an average follow-up of 34 months (range, 24-57). Pre- and postoperative clinical examination included range of motion assessment, isometric strength testing (Isobex, Cursor AG, Bern, Switzerland), and standardized subjective questionnaire for calculation of Constant-Murley scores (CS), as well as the subjective shoulder value (SSV).3 The results were expressed as absolute point scores,
as well as a percentage of age- and gender-matched normal shoulder scores.27Prior to surgery, all patients underwent radiographic analysis consisting of plain radiographs in the anteroposterior and axillary lateral projections. Osteoarthritis was graded by the method of Samilson and Prieto.21 Acromiohumeral distance (ACHD) was defined as the perpendicular distance between the apex of the humeral head and the undersurface of the acromion made in neutral rotation.In addition, all patients underwent standardized magnetic resonance arthrography (Siemens, 1.5T Avanto, Steinhaussen, Switzerland). All plain radiographs and magnetic resonance images were reviewed by three independent reviewers, including one attending musculoskeletal radiologist (MRS). Tears of the teres minor tendon were determined using both the sagittal oblique sections, as well as the coronal sections (Figure 1).Fatty infiltration was graded according to Goutallier using the sagittal oblique sections.4,13
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Figure 2 A 52-year-old man who underwent LDTT for a massive right posterosuperior rotator cuff tear.Prior to surgery, he had pseudoparalysis to scapular plane abduction and external rotation with a significant lag to maximal passive external rotation.Preoperative MRI indicated a partial tear of the teres minor with no fatty infiltration. A and B, At 42 months postoperatively, he has recovered forward elevation (C), external rotation (D), and strength in abduction, and is pain-free.
Surgical technique and rehabilitation Surgery was performed under general anesthesia combined with patient-controlled interscalene analgesia (PCIA) in order to facilitate early passive mobilization postoperatively.The technique of LDTT has been previously described in detail.6,8,9,12 Prior to transfer off the table, the patient was placed into an abduction brace (SOBER Abductor, Pharmap, Crolles, France) at 45 of abduction and 45 of external rotation, which was then worn continuously for 6 weeks following surgery. Passive range of motion exercises with the arm maintained in slight external rotation, and isometric contraction
of the deltoid were initiated on postoperative day 1. The splint was discontinued after 6 weeks, at which time active external rotation and abduction, as well as passive internal rotation, were initiated. Strengthening exercises were not allowed until 3 months following surgery and continued for 6 to 9 months.
Statistical analysis Statistical analysis was performed by a professional statistical consultant.The outcome data were nonparametrically distributed according to the Shapiro-Wilk test. Therefore,
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Figure 3 Comparison of average pain scores preoperatively versus postoperatively following LDTT.
Figure 4 Comparison of average active external rotation, forward flexion, and abduction in all patients preoperatively versus postoperatively following LDTT.
preoperative and follow-up data were compared using the Wilcoxon signed rank test with statistical significance defined as P<.05. Correlations were performed using Spearman’s rho coefficient.
RESULTS All patients had complete tears of the supraspinatus and infraspinatus tendons with retraction and advanced fatty infiltration of Goutallier grade 3 or above. None had clinical or radiographic evidence of disruption of the subscapularis. Radiographs and MRI images were reviewed by 3 blinded independent examiners, and the average of their ratings was used for further statistical analysis. Preoperative fatty infiltration of the supraspinatus was grade 3 in 13 patients (59%) and grade 4 in 9 patients (41%); fatty infiltration of the infraspinatus was grade 3 in 15 patients (68%) and grade 4 in 7
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patients (32%). The subscapularis displayed fatty infiltration of grade 0 in 11 patients (50%); grade 1 in 9 patients (41%); and grade 2 in 2 patients (9%). Fatty infiltration of the teres minor was Goutallier stage 0 in 5 patients (23%); stage 1 in 6 patients (27%); stage 2 in 4 patients (18%); stage 3 in 6 patients (27%); and stage 4 in 1 patient (5%). Thus, there were 15 patients with mild to moderate fatty infiltration and 7 patients with severe fatty infiltration of the teres minor. Eleven patients (50%) had partial tears and 2 patients (9%) had complete tears of the teres minor tendon. Patients gained statistically significant improvements in pain and strength scores, as well as abduction, external rotation, and flexion following LDTT at an average of 34 months following surgery (Figure 2). The average pain score improved from 7 points preoperatively to 12 (out of 15) points at the time of follow-up (P ¼ .001) (Figure 3). Mean strength improved from 1.2 kg preoperatively to 2.1 kg postoperatively (P ¼.01). Internal rotation did not improve following LDTT. Active abduction improved from 103 preoperatively to 123 postoperatively (P ¼ .018), active external rotation from 16 to 30 (P ¼ .012), and active flexion from 117 to 134 (P ¼ .03) (Figure 4). Constant scores (CS%) improved from an average of 48 points preoperatively to 62 points postoperatively (P ¼.003) and age-adjusted CS% from 56 to 72 points (P ¼ .002). The SSV, which reflects the patient’s overall perception of the percentage improvement following surgery, improved from 24% preoperatively to 68% postoperatively (P < .001) (Table I). Osteoarthritis increased from stage 0.8 to 1.0 and the ACHD decreased from 6.3 to 5.5 mm, on average, following LDTT; but these were not statistically significant. The presence of a partial or complete tear of the teres minor tendon preoperatively was associated with worse preoperative overall CS% (43 vs 56, P ¼ .024), age-adjusted CS% (52% vs 61%, P ¼ .04), and increased fatty infiltration of the teres minor muscle (stage 2.2 vs .9, P ¼ .004). Furthermore, the presence of a tear of the teres minor was associated with worse preoperative external rotation (6 vs 32 , P ¼ .007) but was not correlated with postoperative improvements in range of motion or functional score. Fatty infiltration of the teres minor less than or equal to stage 2 (group A) was associated with better preoperative range of motion and functional scores compared to patients with fatty infiltration greater than stage 2 (group B) (Tables II and III). Mean preoperative external rotation in group A was 21 compared to 6 in group B (P ¼ .001), flexion 136 vs 79 (P ¼ .002), and abduction 122 vs 63 (P ¼ .015) (Table IV). Similarly, mean preoperative constant score averaged 55 in group A compared to 34 in group B (P ¼.002), and age-adjusted constant score was 63 in group A
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Table I Summary of preoperative function and teres minor integrity versus postoperative function (entire study group)
Patient
Age
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
62 59 63 52 58 59 65 51 67 49 58 55 56 68 59 67 59 51 65 55 40 51
Mean value Standard deviation P value
58 6.9
TM TEAR pre-op
TM FI pre
CS pre
CS post
CS% pre
CS % post
SSV % pre
SSV % post
ER: pre
ER: post
AB: pre
AB: post
Flex: pre
Flex: post
Yes Partial Partial Partial Partial Partial No No Partial No No No No Yes No Partial No No Partial Partial Partial Partial
4 2 2 0 3 1 0 2 2 3 0 0 1 3 1 1 1 0 3 3 3 1
28 59 25 64 46 57 67 62 37 18 55 44 67 17 56 64 65 71 30 42 59 36
34 76 38 86 78 79 82 77 40 25 82 77 79 63 76 70 49 37 44 73 54 50
31 66 34 70 51 63 81 67 53 20 51 49 74 20 62 91 72 77 42 58 63 39
41 84 54 96 87 88 99 85 57 27 100 86 88 76 84 100 54 41 63 62 59 56
0 10 0 50 30 50 10 0 0 0 10 30 60 10 40 40 50 20 20 50 25 20
80 60 50 98 90 80 95 80 80 80 50 100 90 50 60 66 55 50 20 50 50 60
0 0 40 10 0 40 45 30 0 50 40 30 10 0 0 15 70 10 30 30 10 10
0 60 30 40 40 40 30 60 10 25 30 80 0 0 30 0 70 35 0 60 10 20
80 160 60 120 120 170 170 180 40 20 110 50 170 50 75 180 170 90 45 45 80 85
60 170 90 140 170 180 180 160 40 45 175 100 170 140 170 170 40 100 130 60 125 90
90 160 60 170 150 170 170 160 35 30 135 60 170 40 160 170 170 160 45 50 150 90
120 170 80 160 155 180 180 160 40 50 160 140 170 140 160 160 150 110 130 60 150 130
1.6 1.3
48 17
62 19
56 19
72 21
24 19
68 20
16 24
30 26
103 54
123 50
118 55
134 42
0.003
0.002
<0.001
0.012
0.018
0.03
AB, active abduction; CS, constant score; CS%, age-adjusted constant score; ER, active external rotation; Flex, active forward elevation. SSV%, subjective shoulder value; TM TEAR, tear of teres minor; TM FI, fatty infiltration of teres minor.
compared to 40 in group B (P ¼.007). Postoperatively, patients in group B showed inferior overall and ageadjusted CS%, external rotation, and flexion (Figures 5 and 6). Mean postoperative CS% was 67 in group A compared to 53 in group B (P ¼ .015), and ageadjusted CS% 78% vs 59% (P ¼ .003). Postoperative external rotation averaged 36 in group A compared to 16 in group B (P ¼.009) and flexion 143 vs 115 (P ¼ .012). There was no association between increased fatty infiltration of the teres minor and whether or not surgery was performed in a primary or revision setting. Preoperative fatty infiltration of the supraspinatus or infraspinatus had no correlation on outcome, functional scores, or range of motion following LDTT. However, preoperative fatty infiltration of the supraspinatus was associated with increased fatty infiltration of the infraspinatus (P ¼ .02). DISCUSSION In the present study, LDTT offered an effective solution for massive, irreparable tears of the posterosupe-
rior rotator cuff associated with significant pain and dysfunction, especially with respect to active external rotation and the ability to control the arm in space in the partially abducted position. Other investigators have reached this conclusion.2,6,12 As previously reported, while the degree of improvement in range of motion and strength scores were small, overall improvement in CS% and especially the subjective shoulder value were substantial reflecting the subjective benefit of the procedure for the patients.9 Despite the fact that LDTT seems to be effective in relieving pain and improving function, it remains unclear which factors are predictive of favorable outcomes following this procedure. Warner and Parsons have demonstrated that LDTT for revision surgery results in more limited gains in patient satisfaction and functional scores than primary LDTT. This remains controversial as Miniaci et al showed significant improvements in functional outcome scores at a mean follow-up of 51 months following LDTT for revision offailed rotator cuff repairs.20 We have reported nearly comparable improvements in pain relief and function following LDTT in either primary or revision situations.9
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Table II Summary of preoperative function and teres minor integrity versus postoperative function (group A)
Mean value Standard deviation
Age
TM TEAR
59 63 52 59 65 51 67 58 55 56 59 67 59 51 51
Partial Partial Partial Partial No No Partial No No No No Partial No No Partial
TM FI pre-op
58 5.6
CS pre
CS post
CS% pre
CS % post
SSV % pre
SSV % post
ER: pre
ER: post
AB: pre
AB: post
Flex: pre
Flex: post
2 2 0 1 0 2 2 0 0 1 1 1 1 0 1
59 25 64 57 67 62 37 55 44 67 56 64 65 71 36
76 38 86 79 82 77 40 82 77 79 76 70 49 37 50
66 34 70 63 81 67 53 51 49 74 62 91 72 77 39
84 54 96 88 99 85 57 100 86 88 84 100 54 41 56
10 0 50 50 10 0 0 10 30 60 40 40 50 20 20
60 50 98 80 95 80 80 50 100 90 60 66 55 50 60
0 40 10 40 45 30 0 40 30 10 0 15 70 10 10
60 30 40 40 30 60 10 30 80 0 30 0 70 35 20
160 60 120 170 170 180 40 110 50 170 75 180 170 90 85
170 90 140 180 180 160 40 175 100 170 170 170 40 100 90
160 60 170 170 170 160 35 135 60 170 160 170 170 160 90
170 80 160 180 180 160 40 160 140 170 160 160 150 110 130
0.9 0.8
55 13
67 18
63 15
78 19
26 21
72 18
21 22
36 24
122 52
132 49
136 48
143 39
AB, active abduction; CS, constant score; CS%, age-adjusted constant score; ER, active external rotation; Flex, active forward elevation. SSV%, subjective shoulder value; TM TEAR, tear of teres minor; TM FI, fatty infiltration of teres minor.
Table III Summary of preoperative function and teres minor integrity versus postoperative function (group B)
Mean value Standard deviation
Age
TM TEAR
TM FI pre-op
CS pre
CS post
CS% pre
CS % post
SSV % pre
SSV % post
ER: pre
ER: post
AB: pre
AB: post
Flex: pre
Flex: post
62 58 49 68 65 55 40
Yes Partial No Yes Partial Partial Partial
4 3 3 3 3 3 3
28 46 18 17 30 42 59
34 78 25 63 44 73 54
31 51 20 20 42 58 63
41 87 27 76 63 62 59
0 30 0 10 20 50 25
80 90 80 50 20 50 50
0 0 50 0 30 30 10
0 40 25 0 0 60 -10
80 120 20 50 45 45 80
60 170 45 140 130 60 125
90 150 30 40 45 50 150
120 155 50 140 130 60 150
3.1 0.4
34 15
53 19
40 17
59 20
19 17
60 24
5 26
16 25
62 32
104 48
79 51
115 42
57 9.7
AB, active abduction; CS, constant score; CS%, age-adjusted constant score; ER, active external rotation; Flex, active forward elevation. SSV%, subjective shoulder value; TM TEAR, tear of teres minor; TM FI, fatty infiltration of teres minor.
Recently, Iannotti et al reported on 14 patients who underwent LDTT for irreparable posterosuperior rotator cuff tears at a minimum of 2 years following surgery.16 They concluded that in-phase contraction of the latissimus dorsi muscle based on postoperative electromyography, as well as the degree of preoperative active forward elevation and external rotation, were associated with improved outcomes following LDTT. Subscapularis integrity has been shown to be relevant for LDTT.2,6,9 This parameter was controlled in
this study and, therefore, did not influence the results.9 While the subscapularis seems to play an important role in the success of LDTT, it has remained unknown to what degree structural integrity and fatty infiltration of the teres minor musculotendinous unit may influence the results of LDTT. Keating18 and Herzberg15 have elegantly examined the detailed biomechanical contributions of various muscles of the rotator cuff and shoulder girdle on shoulder function. Keating has shown that the supraspinatus contributes little (15%)
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Table IV Comparison of preoperative and postoperative function between group A and group B
Group A mean Group A St.D. Group B mean Group B St.D. P value
TM FI Pre-op
CS pre
CS post
CS% pre
CS % post
SSV % pre
SSV % post
ER: pre
ER: post
AB: pre
AB: post
Flex: pre
Flex: post
0.9 0.7 3.1 0.4
55 13 34 15
67 18 53 19 0.015
63 15 41 17
78 19 59 20 0.012
26 20 19 17
72 18 60 24
21 22 6 26
36 23 16 26 0.016
122 52 63 33
132 50 104 48
136 48 79 51
143 39 115 42 0.012
AB, active abduction; CS, constant score; CS%, age-adjusted constant score; ER, active external rotation; Flex, active forward elevation. SSV%, subjective shoulder value; TM TEAR, tear of teres minor; TM FI, fatty infiltration of teres minor.
Figure 5 Comparison of average age-adjusted constant score (CS%), subjective shoulder value (SSV), active abduction, forward flexion, and external rotation in group B.
Figure 6 Comparison of average age-adjusted constant score (CS%), subjective shoulder value (SSV), active abduction, forward flexion, and external rotation in group A.
to the overall abduction moment arm of the shoulder, compared to the subscapularis (52%) and the combined effect of the infraspinatus and teres minor (33%).18 Herzberg has shown that, while the physiological cross-sectional area of the teres minor, and thus the potential force generated is relatively small compared to the other 3 rotator cuff muscles, the potential excursion is actually greatest.Thus, an intact teres minor may improve the efficiency of the tendon transfer in external rotation, especially given the fact that the latissimus dorsi has the greatest excursion of the 13 shoulder girdle muscles examined by Herzberg.15 In this series, partial and complete tears were associated with worse preoperative constant scores, as well as external rotation. Furthermore, partial and complete tears of the teres minor were associated with more advanced fatty infiltration.5,7,13,17 Interestingly, fatty infiltration of the teres minor influenced the results of LDTT significantly, whereas the presence or absence of tendon tear did not. Fatty infiltration of the teres minor greater than stage 2 was associated with worse preoperative and postoperative pain and functional scores, as well as limited active external ro-
tation and forward elevation. Fatty infiltration has been shown to be predictive of structural behavior of the musculotendinous unit in animal models of rotator cuff injury and to correlate with overall shoulder function and biomechanics.10,11,19 Thus, based on this investigation, while the presence or absence of a tear of the teres minor tendon may have some predictive value prior to surgery with regard to motion and functional status, the degree of fatty infiltration seems to play a more critical role which continues after LDTT. In conclusion, LDTT is an effective treatment for massive, irreparable posterosuperior rotator cuff tears and leads to substantial clinical improvement. However, when performing LDTT, fatty infiltration of the teres minor should be assessed by MRI prior to surgery, as it is predictive of the ultimate result. We thank Valentin Rousson, PhD, for assistance with the statistical methods and analysis. REFERENCES
1. Aldridge JM III, Atkinson TS, Mallon WJ. Combined pectoralis major and latissimus dorsi tendon transfer for massive rotator cuff deficiency. J Shoulder Elbow Surg 2004;13:621-9.
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2. Aoki M, Okamura K, Fukushima S, Takahashi T, Ogino T. Transfer of latissimus dorsi for irreparable rotator-cuff tears. J Bone Joint Surg Br 1996;78:761-6. 3. Constant CR, Murley AH. A clinical method of functional assessment of the shoulder. Clin Orthop 1987;214:160-4. 4. Fuchs B, Weishaupt D, Zanetti M, Hodler J, Gerber C. Fatty degeneration of the muscles of the rotator cuff: assessment by computed tomography versus magnetic resonance imaging. J Shoulder Elbow Surg 1999;8:599-605. 5. Galatz LM, Ball CM, Teefey SA, Middleton WD, Yamaguchi K. The outcome and repair integrity of completely arthroscopically repaired large and massive rotator cuff tears. J Bone Joint Surg Am 2004;86A:219-24. 6. Gerber C. Latissimus dorsi transfer for the treatment of irreparable tears of the rotator cuff. Clin Orthop Relat Res 1992;275:152-60. 7. Gerber C, Fuchs B, Hodler J. The results of repair of massive tears of the rotator cuff. J Bone Joint Surg Am 2000;82:505-15. 8. Gerber C, Hersche O. Tendon transfers for the treatment of irreparable rotator cuff defects. Orthop Clin North Am 1997;28:195-203. 9. Gerber C, Maquieira G, Espinosa N. Latissimus dorsi transfer for the treatment of irreparable rotator cuff tears. J Bone Joint Surg Am 2006;88:113-20. 10. Gerber C, Meyer DC, Schneeberger AG, Hoppeler H, von Rechenberg B. Effect of tendon release and delayed repair on the structure of the muscles of the rotator cuff: an experimental study in sheep. J Bone Joint Surg Am 2004;86A:1973-82. 11. Gerber C, Schneeberger AG, Perren SM, Nyffeler RW. Experimental rotator cuff repair. A preliminary study. J Bone Joint Surg Am 1999;81:1281-90. 12. Gerber C, Vinh TS, Hertel R, Hess CW. Latissimus dorsi transfer for the treatment of massive tears of the rotator cuff. A preliminary report. Clin Orthop Relat Res 1988;232:51-61. 13. Goutallier D, Postel JM, Bernageau J, Lavau L, Voisin MC. Fatty muscle degeneration in cuff ruptures. Pre- and postoperative evaluation by CT scan. Clin Orthop Relat Res 1994;304:78-83. 14. Harryman DT II, Mack LA, Wang KY, Jackins SE, Richardson ML, Matsen FA III. Repairs of the rotator cuff. Correlation of functional results with integrity of the cuff. J Bone Joint Surg Am 1991;73:982-9.
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15. Herzberg G, Urien JP, Dimnet J. Potential excursion and relative tension of muscles in the shoulder girdle: relevance to tendon transfers. J Shoulder Elbow Surg 1999;8:430-7. 16. Iannotti JP, Hennigan S, Herzog R, et al. Latissimus dorsi tendon transfer for irreparable posterosuperior rotator cuff tears. J Bone Joint Surg Am 2006;88A:342-8. 17. Jost B, Pfirrmann CW, Gerber C, Switzerland Z. Clinical outcome after structural failure of rotator cuff repairs. J Bone Joint Surg Am 2000;82:304-14. 18. Keating JF, Waterworth P, Shaw-Dunn J, Crossan J. The relative strengths of the rotator cuff muscles. A cadaver study. J Bone Joint Surg Br 1993;75:137-40. 19. Meyer DC, Hoppeler H, von Rechenberg B, Gerber C. A pathomechanical concept explains muscle loss and fatty muscular changes following surgical tendon release. J Orthop Res 2004; 22:1004-7. 20. Miniaci A, MacLeod M. Transfer of the latissimus dorsi muscle after failed repair of a massive tear of the rotator cuff. A two- to five-year review. J Bone Joint Surg Am 1999;81:1120-7. 21. Samilson RL, Prieto V. Dislocation arthropathy of the shoulder. J Bone Joint Surg Am 1983;65:456-60. 22. Thompson WO, Debski RE, Boardman ND III, et al. A biomechanical analysis of rotator cuff deficiency in a cadaveric model. Am J Sports Med 1996;24:286-92. 23. Walch G, Ascani C, Boulahia A, Nove-Josserand L, Edwards TB. Static posterior subluxation of the humeral head: an unrecognized entity responsible for glenohumeral osteoarthritis in the young adult. J Shoulder Elbow Surg 2002;11:309-14. 24. Warner JJ. Management of massive irreparable rotator cuff tears: the role of tendon transfer. Instr Course Lect 2001;50:63-71. 25. Warner JJ, Gerber C. Treatment of massive rotator cuff tears:posterior-superior and anterior-superior. In: Iannotti JP, editor. The rotator cuff:current concepts and complex problems. Rosemont: American Academy of Orthopaedic Surgeons; 1998. p. 59-94. 26. Warner JJ, Parsons IM. Latissimus dorsi tendon transfer: a comparative analysis of primary and salvage reconstruction of massive, irreparable rotator cuff tears. J Shoulder Elbow Surg 2001;10:514-21. 27. Yian EH, Ramappa AJ, Arneberg O, Gerber C. The Constant score in normal shoulders. J Shoulder Elbow Surg 2005;14: 128-33.
In patients with irreparable rotator cuff tears, latissimus dorsi tendon transfer (LDTT) can be effective in improving pain and function. However, the results are variable, and the factors that predict good outcomes are poorly understood. The purpose of this study was to investigate whether the integrity of the teres minor musculotendinous unit is predictive of outcome following LDTT. Twenty-two consecutive patients who underwent LDTT for massive, irreparable posterosuperior rotator cuff tears were retrospectively reviewed. Sixteen men and 6 women with a mean age of 58 years (range, 40-68) were analyzed at an average follow-up of 34 months (range, 24-57).Standardized MRI images of all patients were reviewed by 3 independent reviewers. Fatty infiltration of the teres minor was Goutallier stage 0 in 5 patients; stage 1 in 6; stage 2 in 4; stage 3 in 6; and stage 4 in 1. Eleven patients (50%) had partial tears and 2 (9%) had complete tears of the teres minor tendon. Following LDTT, the mean absolute constant score improved from 48 to 62 points ( P ¼ .003), age-adjusted constant score improved from 56% to 72% ( P ¼ .002), and the subjective shoulder value improved from 24% to 68% ( P < .001). Fatty infiltration of the teres minor less than or equal to stage 2 was associated with a better postoperative constant score (67 vs 53, P ¼ .015); age-adjusted constant score (78% vs 59%, P ¼ .012); active external rotation (36 vs 16 , P ¼.016); and active elevation (143 vs 115 , P ¼.012) relative to patients with fatty infiltration greater than stage 2. The presence or absence of a tear of the tendon had no significant effect on outcome. In conclusion, when performing LDTT for massive irreparable posterosuperior rotator cuff tears, fatty infiltration of the teres minor should be considered prior to surgery, as it is predictive of outcome. (J Shoulder Elbow Surg 2007;16:727-734.) From the University of Zurich, Balgrist University Hospital, Zurich, Switzerland. Reprint requests: Christian Gerber, MD, Department of Orthopedics, University of Zurich, Balgrist, Forchstrasse 340, CH-8008 Zurich, Switzerland (E-mail: [email protected]). Copyright ª 2007 by Journal of Shoulder and Elbow Surgery Board of Trustees. 1058-2746/2007/$32.00 doi:10.1016/j.jse.2007.02.128
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rreparable rotator cuff tears are found in a small proportion of patients, as approximately 95% of rotator cuff tears considered for operative treatment are reparable at the time of surgery.7,25While the prevalence of irreparable tendon tears is low, they profoundly affect the functional capacity of patients and can be associated with significant levels of pain and dysfunction.Furthermore, even in the setting of reparable tears, it is becoming clear that fatty infiltration is not reversible and that larger tears with advanced fatty infiltration of the rotator cuff musculature carry a higher risk of failure and are associated with inferior clinical outcomes.5,7,13,14,17 The latissimus dorsi tendon transfer (LDTT) offers a promising solution in the treatment of irreparable tears of the posterosuperior rotator cuff, and has been shown to yield favorable results at mid- to longterm follow-up.1,6,8,9,12,24,26 However, the results have been found to be variable, and the factors which are predictive of good outcome are poorly understood. Although the biomechanical role of the teres minor in rotator cuff function has been studied extensively, it is unclear how it may impact the clinical results of LDTT.15,18,22 The purpose of this study was to investigate whether the structural integrity and degree of fatty infiltration of the teres minor musculotendinous unit prior to surgery is predictive of outcome following LDTT. MATERIALS AND METHODS Twenty-two consecutive patients who underwent LDTT for massive, irreparable posterosuperior rotator cuff tears were retrospectively reviewed clinically and radiographically. Prior to surgery, all patients provided written, informed consent for the procedure. Indications for surgery included moderate to severe pain and subjectively unacceptable dysfunction that was refractory to conservative treatment. Massive, irreparable tears of the supraspinatus and infraspinatus tendons were defined as those with preoperative fatty infiltration greater than stage 2, an acromiohumeral distance of less than 7 ml on a standardized true anteroposterior radiograph, or those which were not surgically reparable at the time of surgery. Conservative treatment consisted of supervised physical therapy and the use of oral nonsteroidal anti-inflammatory medication for a minimum of 6 months. Patients with subscapularis tears; glenohumeral arthritis (Samilson and Prieto Grade > 1);21 static anterior or posterior
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Figure 1 Magnetic resonance image parallel to the glenoid plane through the base of the coracoid. A, The subscapularis, supraspinatus, infraspinatus, and teres minor (arrow) are homogeneous, convex, and voluminous in a normal rotator cuff. B, In a massive posterosuperior tear, the subscapularis is normal, but the supraspinatus and infraspinatus show fatty infiltration and atrophy.In this case, the teres minor (arrow) shows no evidence of fatty infiltration and atrophy.
humeral head subluxation;23 dynamic anterosuperior humeral head subluxation; or excessive superior humeral migration (acromiohumeral distance < 5 mm) were excluded. The study (N ¼ 22) consisted of 16 men and 6 women with a mean age of 58 years (range, 40-68).Surgery was performed on 15 right shoulders and 7 left shoulders, and the dominant arm was involved in 16 cases (73%). Five (23%) were revision surgeries, which consisted of 4 failed open and 1 failed arthroscopic rotator cuff repair. Following surgery, patients were evaluated at regular intervals with an average follow-up of 34 months (range, 24-57). Pre- and postoperative clinical examination included range of motion assessment, isometric strength testing (Isobex, Cursor AG, Bern, Switzerland), and standardized subjective questionnaire for calculation of Constant-Murley scores (CS), as well as the subjective shoulder value (SSV).3 The results were expressed as absolute point scores,
as well as a percentage of age- and gender-matched normal shoulder scores.27Prior to surgery, all patients underwent radiographic analysis consisting of plain radiographs in the anteroposterior and axillary lateral projections. Osteoarthritis was graded by the method of Samilson and Prieto.21 Acromiohumeral distance (ACHD) was defined as the perpendicular distance between the apex of the humeral head and the undersurface of the acromion made in neutral rotation.In addition, all patients underwent standardized magnetic resonance arthrography (Siemens, 1.5T Avanto, Steinhaussen, Switzerland). All plain radiographs and magnetic resonance images were reviewed by three independent reviewers, including one attending musculoskeletal radiologist (MRS). Tears of the teres minor tendon were determined using both the sagittal oblique sections, as well as the coronal sections (Figure 1).Fatty infiltration was graded according to Goutallier using the sagittal oblique sections.4,13
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Figure 2 A 52-year-old man who underwent LDTT for a massive right posterosuperior rotator cuff tear.Prior to surgery, he had pseudoparalysis to scapular plane abduction and external rotation with a significant lag to maximal passive external rotation.Preoperative MRI indicated a partial tear of the teres minor with no fatty infiltration. A and B, At 42 months postoperatively, he has recovered forward elevation (C), external rotation (D), and strength in abduction, and is pain-free.
Surgical technique and rehabilitation Surgery was performed under general anesthesia combined with patient-controlled interscalene analgesia (PCIA) in order to facilitate early passive mobilization postoperatively.The technique of LDTT has been previously described in detail.6,8,9,12 Prior to transfer off the table, the patient was placed into an abduction brace (SOBER Abductor, Pharmap, Crolles, France) at 45 of abduction and 45 of external rotation, which was then worn continuously for 6 weeks following surgery. Passive range of motion exercises with the arm maintained in slight external rotation, and isometric contraction
of the deltoid were initiated on postoperative day 1. The splint was discontinued after 6 weeks, at which time active external rotation and abduction, as well as passive internal rotation, were initiated. Strengthening exercises were not allowed until 3 months following surgery and continued for 6 to 9 months.
Statistical analysis Statistical analysis was performed by a professional statistical consultant.The outcome data were nonparametrically distributed according to the Shapiro-Wilk test. Therefore,
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Figure 3 Comparison of average pain scores preoperatively versus postoperatively following LDTT.
Figure 4 Comparison of average active external rotation, forward flexion, and abduction in all patients preoperatively versus postoperatively following LDTT.
preoperative and follow-up data were compared using the Wilcoxon signed rank test with statistical significance defined as P<.05. Correlations were performed using Spearman’s rho coefficient.
RESULTS All patients had complete tears of the supraspinatus and infraspinatus tendons with retraction and advanced fatty infiltration of Goutallier grade 3 or above. None had clinical or radiographic evidence of disruption of the subscapularis. Radiographs and MRI images were reviewed by 3 blinded independent examiners, and the average of their ratings was used for further statistical analysis. Preoperative fatty infiltration of the supraspinatus was grade 3 in 13 patients (59%) and grade 4 in 9 patients (41%); fatty infiltration of the infraspinatus was grade 3 in 15 patients (68%) and grade 4 in 7
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patients (32%). The subscapularis displayed fatty infiltration of grade 0 in 11 patients (50%); grade 1 in 9 patients (41%); and grade 2 in 2 patients (9%). Fatty infiltration of the teres minor was Goutallier stage 0 in 5 patients (23%); stage 1 in 6 patients (27%); stage 2 in 4 patients (18%); stage 3 in 6 patients (27%); and stage 4 in 1 patient (5%). Thus, there were 15 patients with mild to moderate fatty infiltration and 7 patients with severe fatty infiltration of the teres minor. Eleven patients (50%) had partial tears and 2 patients (9%) had complete tears of the teres minor tendon. Patients gained statistically significant improvements in pain and strength scores, as well as abduction, external rotation, and flexion following LDTT at an average of 34 months following surgery (Figure 2). The average pain score improved from 7 points preoperatively to 12 (out of 15) points at the time of follow-up (P ¼ .001) (Figure 3). Mean strength improved from 1.2 kg preoperatively to 2.1 kg postoperatively (P ¼.01). Internal rotation did not improve following LDTT. Active abduction improved from 103 preoperatively to 123 postoperatively (P ¼ .018), active external rotation from 16 to 30 (P ¼ .012), and active flexion from 117 to 134 (P ¼ .03) (Figure 4). Constant scores (CS%) improved from an average of 48 points preoperatively to 62 points postoperatively (P ¼.003) and age-adjusted CS% from 56 to 72 points (P ¼ .002). The SSV, which reflects the patient’s overall perception of the percentage improvement following surgery, improved from 24% preoperatively to 68% postoperatively (P < .001) (Table I). Osteoarthritis increased from stage 0.8 to 1.0 and the ACHD decreased from 6.3 to 5.5 mm, on average, following LDTT; but these were not statistically significant. The presence of a partial or complete tear of the teres minor tendon preoperatively was associated with worse preoperative overall CS% (43 vs 56, P ¼ .024), age-adjusted CS% (52% vs 61%, P ¼ .04), and increased fatty infiltration of the teres minor muscle (stage 2.2 vs .9, P ¼ .004). Furthermore, the presence of a tear of the teres minor was associated with worse preoperative external rotation (6 vs 32 , P ¼ .007) but was not correlated with postoperative improvements in range of motion or functional score. Fatty infiltration of the teres minor less than or equal to stage 2 (group A) was associated with better preoperative range of motion and functional scores compared to patients with fatty infiltration greater than stage 2 (group B) (Tables II and III). Mean preoperative external rotation in group A was 21 compared to 6 in group B (P ¼ .001), flexion 136 vs 79 (P ¼ .002), and abduction 122 vs 63 (P ¼ .015) (Table IV). Similarly, mean preoperative constant score averaged 55 in group A compared to 34 in group B (P ¼.002), and age-adjusted constant score was 63 in group A
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Table I Summary of preoperative function and teres minor integrity versus postoperative function (entire study group)
Patient
Age
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
62 59 63 52 58 59 65 51 67 49 58 55 56 68 59 67 59 51 65 55 40 51
Mean value Standard deviation P value
58 6.9
TM TEAR pre-op
TM FI pre
CS pre
CS post
CS% pre
CS % post
SSV % pre
SSV % post
ER: pre
ER: post
AB: pre
AB: post
Flex: pre
Flex: post
Yes Partial Partial Partial Partial Partial No No Partial No No No No Yes No Partial No No Partial Partial Partial Partial
4 2 2 0 3 1 0 2 2 3 0 0 1 3 1 1 1 0 3 3 3 1
28 59 25 64 46 57 67 62 37 18 55 44 67 17 56 64 65 71 30 42 59 36
34 76 38 86 78 79 82 77 40 25 82 77 79 63 76 70 49 37 44 73 54 50
31 66 34 70 51 63 81 67 53 20 51 49 74 20 62 91 72 77 42 58 63 39
41 84 54 96 87 88 99 85 57 27 100 86 88 76 84 100 54 41 63 62 59 56
0 10 0 50 30 50 10 0 0 0 10 30 60 10 40 40 50 20 20 50 25 20
80 60 50 98 90 80 95 80 80 80 50 100 90 50 60 66 55 50 20 50 50 60
0 0 40 10 0 40 45 30 0 50 40 30 10 0 0 15 70 10 30 30 10 10
0 60 30 40 40 40 30 60 10 25 30 80 0 0 30 0 70 35 0 60 10 20
80 160 60 120 120 170 170 180 40 20 110 50 170 50 75 180 170 90 45 45 80 85
60 170 90 140 170 180 180 160 40 45 175 100 170 140 170 170 40 100 130 60 125 90
90 160 60 170 150 170 170 160 35 30 135 60 170 40 160 170 170 160 45 50 150 90
120 170 80 160 155 180 180 160 40 50 160 140 170 140 160 160 150 110 130 60 150 130
1.6 1.3
48 17
62 19
56 19
72 21
24 19
68 20
16 24
30 26
103 54
123 50
118 55
134 42
0.003
0.002
<0.001
0.012
0.018
0.03
AB, active abduction; CS, constant score; CS%, age-adjusted constant score; ER, active external rotation; Flex, active forward elevation. SSV%, subjective shoulder value; TM TEAR, tear of teres minor; TM FI, fatty infiltration of teres minor.
compared to 40 in group B (P ¼.007). Postoperatively, patients in group B showed inferior overall and ageadjusted CS%, external rotation, and flexion (Figures 5 and 6). Mean postoperative CS% was 67 in group A compared to 53 in group B (P ¼ .015), and ageadjusted CS% 78% vs 59% (P ¼ .003). Postoperative external rotation averaged 36 in group A compared to 16 in group B (P ¼.009) and flexion 143 vs 115 (P ¼ .012). There was no association between increased fatty infiltration of the teres minor and whether or not surgery was performed in a primary or revision setting. Preoperative fatty infiltration of the supraspinatus or infraspinatus had no correlation on outcome, functional scores, or range of motion following LDTT. However, preoperative fatty infiltration of the supraspinatus was associated with increased fatty infiltration of the infraspinatus (P ¼ .02). DISCUSSION In the present study, LDTT offered an effective solution for massive, irreparable tears of the posterosupe-
rior rotator cuff associated with significant pain and dysfunction, especially with respect to active external rotation and the ability to control the arm in space in the partially abducted position. Other investigators have reached this conclusion.2,6,12 As previously reported, while the degree of improvement in range of motion and strength scores were small, overall improvement in CS% and especially the subjective shoulder value were substantial reflecting the subjective benefit of the procedure for the patients.9 Despite the fact that LDTT seems to be effective in relieving pain and improving function, it remains unclear which factors are predictive of favorable outcomes following this procedure. Warner and Parsons have demonstrated that LDTT for revision surgery results in more limited gains in patient satisfaction and functional scores than primary LDTT. This remains controversial as Miniaci et al showed significant improvements in functional outcome scores at a mean follow-up of 51 months following LDTT for revision offailed rotator cuff repairs.20 We have reported nearly comparable improvements in pain relief and function following LDTT in either primary or revision situations.9
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Table II Summary of preoperative function and teres minor integrity versus postoperative function (group A)
Mean value Standard deviation
Age
TM TEAR
59 63 52 59 65 51 67 58 55 56 59 67 59 51 51
Partial Partial Partial Partial No No Partial No No No No Partial No No Partial
TM FI pre-op
58 5.6
CS pre
CS post
CS% pre
CS % post
SSV % pre
SSV % post
ER: pre
ER: post
AB: pre
AB: post
Flex: pre
Flex: post
2 2 0 1 0 2 2 0 0 1 1 1 1 0 1
59 25 64 57 67 62 37 55 44 67 56 64 65 71 36
76 38 86 79 82 77 40 82 77 79 76 70 49 37 50
66 34 70 63 81 67 53 51 49 74 62 91 72 77 39
84 54 96 88 99 85 57 100 86 88 84 100 54 41 56
10 0 50 50 10 0 0 10 30 60 40 40 50 20 20
60 50 98 80 95 80 80 50 100 90 60 66 55 50 60
0 40 10 40 45 30 0 40 30 10 0 15 70 10 10
60 30 40 40 30 60 10 30 80 0 30 0 70 35 20
160 60 120 170 170 180 40 110 50 170 75 180 170 90 85
170 90 140 180 180 160 40 175 100 170 170 170 40 100 90
160 60 170 170 170 160 35 135 60 170 160 170 170 160 90
170 80 160 180 180 160 40 160 140 170 160 160 150 110 130
0.9 0.8
55 13
67 18
63 15
78 19
26 21
72 18
21 22
36 24
122 52
132 49
136 48
143 39
AB, active abduction; CS, constant score; CS%, age-adjusted constant score; ER, active external rotation; Flex, active forward elevation. SSV%, subjective shoulder value; TM TEAR, tear of teres minor; TM FI, fatty infiltration of teres minor.
Table III Summary of preoperative function and teres minor integrity versus postoperative function (group B)
Mean value Standard deviation
Age
TM TEAR
TM FI pre-op
CS pre
CS post
CS% pre
CS % post
SSV % pre
SSV % post
ER: pre
ER: post
AB: pre
AB: post
Flex: pre
Flex: post
62 58 49 68 65 55 40
Yes Partial No Yes Partial Partial Partial
4 3 3 3 3 3 3
28 46 18 17 30 42 59
34 78 25 63 44 73 54
31 51 20 20 42 58 63
41 87 27 76 63 62 59
0 30 0 10 20 50 25
80 90 80 50 20 50 50
0 0 50 0 30 30 10
0 40 25 0 0 60 -10
80 120 20 50 45 45 80
60 170 45 140 130 60 125
90 150 30 40 45 50 150
120 155 50 140 130 60 150
3.1 0.4
34 15
53 19
40 17
59 20
19 17
60 24
5 26
16 25
62 32
104 48
79 51
115 42
57 9.7
AB, active abduction; CS, constant score; CS%, age-adjusted constant score; ER, active external rotation; Flex, active forward elevation. SSV%, subjective shoulder value; TM TEAR, tear of teres minor; TM FI, fatty infiltration of teres minor.
Recently, Iannotti et al reported on 14 patients who underwent LDTT for irreparable posterosuperior rotator cuff tears at a minimum of 2 years following surgery.16 They concluded that in-phase contraction of the latissimus dorsi muscle based on postoperative electromyography, as well as the degree of preoperative active forward elevation and external rotation, were associated with improved outcomes following LDTT. Subscapularis integrity has been shown to be relevant for LDTT.2,6,9 This parameter was controlled in
this study and, therefore, did not influence the results.9 While the subscapularis seems to play an important role in the success of LDTT, it has remained unknown to what degree structural integrity and fatty infiltration of the teres minor musculotendinous unit may influence the results of LDTT. Keating18 and Herzberg15 have elegantly examined the detailed biomechanical contributions of various muscles of the rotator cuff and shoulder girdle on shoulder function. Keating has shown that the supraspinatus contributes little (15%)
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Table IV Comparison of preoperative and postoperative function between group A and group B
Group A mean Group A St.D. Group B mean Group B St.D. P value
TM FI Pre-op
CS pre
CS post
CS% pre
CS % post
SSV % pre
SSV % post
ER: pre
ER: post
AB: pre
AB: post
Flex: pre
Flex: post
0.9 0.7 3.1 0.4
55 13 34 15
67 18 53 19 0.015
63 15 41 17
78 19 59 20 0.012
26 20 19 17
72 18 60 24
21 22 6 26
36 23 16 26 0.016
122 52 63 33
132 50 104 48
136 48 79 51
143 39 115 42 0.012
AB, active abduction; CS, constant score; CS%, age-adjusted constant score; ER, active external rotation; Flex, active forward elevation. SSV%, subjective shoulder value; TM TEAR, tear of teres minor; TM FI, fatty infiltration of teres minor.
Figure 5 Comparison of average age-adjusted constant score (CS%), subjective shoulder value (SSV), active abduction, forward flexion, and external rotation in group B.
Figure 6 Comparison of average age-adjusted constant score (CS%), subjective shoulder value (SSV), active abduction, forward flexion, and external rotation in group A.
to the overall abduction moment arm of the shoulder, compared to the subscapularis (52%) and the combined effect of the infraspinatus and teres minor (33%).18 Herzberg has shown that, while the physiological cross-sectional area of the teres minor, and thus the potential force generated is relatively small compared to the other 3 rotator cuff muscles, the potential excursion is actually greatest.Thus, an intact teres minor may improve the efficiency of the tendon transfer in external rotation, especially given the fact that the latissimus dorsi has the greatest excursion of the 13 shoulder girdle muscles examined by Herzberg.15 In this series, partial and complete tears were associated with worse preoperative constant scores, as well as external rotation. Furthermore, partial and complete tears of the teres minor were associated with more advanced fatty infiltration.5,7,13,17 Interestingly, fatty infiltration of the teres minor influenced the results of LDTT significantly, whereas the presence or absence of tendon tear did not. Fatty infiltration of the teres minor greater than stage 2 was associated with worse preoperative and postoperative pain and functional scores, as well as limited active external ro-
tation and forward elevation. Fatty infiltration has been shown to be predictive of structural behavior of the musculotendinous unit in animal models of rotator cuff injury and to correlate with overall shoulder function and biomechanics.10,11,19 Thus, based on this investigation, while the presence or absence of a tear of the teres minor tendon may have some predictive value prior to surgery with regard to motion and functional status, the degree of fatty infiltration seems to play a more critical role which continues after LDTT. In conclusion, LDTT is an effective treatment for massive, irreparable posterosuperior rotator cuff tears and leads to substantial clinical improvement. However, when performing LDTT, fatty infiltration of the teres minor should be assessed by MRI prior to surgery, as it is predictive of the ultimate result. We thank Valentin Rousson, PhD, for assistance with the statistical methods and analysis. REFERENCES
1. Aldridge JM III, Atkinson TS, Mallon WJ. Combined pectoralis major and latissimus dorsi tendon transfer for massive rotator cuff deficiency. J Shoulder Elbow Surg 2004;13:621-9.
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2. Aoki M, Okamura K, Fukushima S, Takahashi T, Ogino T. Transfer of latissimus dorsi for irreparable rotator-cuff tears. J Bone Joint Surg Br 1996;78:761-6. 3. Constant CR, Murley AH. A clinical method of functional assessment of the shoulder. Clin Orthop 1987;214:160-4. 4. Fuchs B, Weishaupt D, Zanetti M, Hodler J, Gerber C. Fatty degeneration of the muscles of the rotator cuff: assessment by computed tomography versus magnetic resonance imaging. J Shoulder Elbow Surg 1999;8:599-605. 5. Galatz LM, Ball CM, Teefey SA, Middleton WD, Yamaguchi K. The outcome and repair integrity of completely arthroscopically repaired large and massive rotator cuff tears. J Bone Joint Surg Am 2004;86A:219-24. 6. Gerber C. Latissimus dorsi transfer for the treatment of irreparable tears of the rotator cuff. Clin Orthop Relat Res 1992;275:152-60. 7. Gerber C, Fuchs B, Hodler J. The results of repair of massive tears of the rotator cuff. J Bone Joint Surg Am 2000;82:505-15. 8. Gerber C, Hersche O. Tendon transfers for the treatment of irreparable rotator cuff defects. Orthop Clin North Am 1997;28:195-203. 9. Gerber C, Maquieira G, Espinosa N. Latissimus dorsi transfer for the treatment of irreparable rotator cuff tears. J Bone Joint Surg Am 2006;88:113-20. 10. Gerber C, Meyer DC, Schneeberger AG, Hoppeler H, von Rechenberg B. Effect of tendon release and delayed repair on the structure of the muscles of the rotator cuff: an experimental study in sheep. J Bone Joint Surg Am 2004;86A:1973-82. 11. Gerber C, Schneeberger AG, Perren SM, Nyffeler RW. Experimental rotator cuff repair. A preliminary study. J Bone Joint Surg Am 1999;81:1281-90. 12. Gerber C, Vinh TS, Hertel R, Hess CW. Latissimus dorsi transfer for the treatment of massive tears of the rotator cuff. A preliminary report. Clin Orthop Relat Res 1988;232:51-61. 13. Goutallier D, Postel JM, Bernageau J, Lavau L, Voisin MC. Fatty muscle degeneration in cuff ruptures. Pre- and postoperative evaluation by CT scan. Clin Orthop Relat Res 1994;304:78-83. 14. Harryman DT II, Mack LA, Wang KY, Jackins SE, Richardson ML, Matsen FA III. Repairs of the rotator cuff. Correlation of functional results with integrity of the cuff. J Bone Joint Surg Am 1991;73:982-9.
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15. Herzberg G, Urien JP, Dimnet J. Potential excursion and relative tension of muscles in the shoulder girdle: relevance to tendon transfers. J Shoulder Elbow Surg 1999;8:430-7. 16. Iannotti JP, Hennigan S, Herzog R, et al. Latissimus dorsi tendon transfer for irreparable posterosuperior rotator cuff tears. J Bone Joint Surg Am 2006;88A:342-8. 17. Jost B, Pfirrmann CW, Gerber C, Switzerland Z. Clinical outcome after structural failure of rotator cuff repairs. J Bone Joint Surg Am 2000;82:304-14. 18. Keating JF, Waterworth P, Shaw-Dunn J, Crossan J. The relative strengths of the rotator cuff muscles. A cadaver study. J Bone Joint Surg Br 1993;75:137-40. 19. Meyer DC, Hoppeler H, von Rechenberg B, Gerber C. A pathomechanical concept explains muscle loss and fatty muscular changes following surgical tendon release. J Orthop Res 2004; 22:1004-7. 20. Miniaci A, MacLeod M. Transfer of the latissimus dorsi muscle after failed repair of a massive tear of the rotator cuff. A two- to five-year review. J Bone Joint Surg Am 1999;81:1120-7. 21. Samilson RL, Prieto V. Dislocation arthropathy of the shoulder. J Bone Joint Surg Am 1983;65:456-60. 22. Thompson WO, Debski RE, Boardman ND III, et al. A biomechanical analysis of rotator cuff deficiency in a cadaveric model. Am J Sports Med 1996;24:286-92. 23. Walch G, Ascani C, Boulahia A, Nove-Josserand L, Edwards TB. Static posterior subluxation of the humeral head: an unrecognized entity responsible for glenohumeral osteoarthritis in the young adult. J Shoulder Elbow Surg 2002;11:309-14. 24. Warner JJ. Management of massive irreparable rotator cuff tears: the role of tendon transfer. Instr Course Lect 2001;50:63-71. 25. Warner JJ, Gerber C. Treatment of massive rotator cuff tears:posterior-superior and anterior-superior. In: Iannotti JP, editor. The rotator cuff:current concepts and complex problems. Rosemont: American Academy of Orthopaedic Surgeons; 1998. p. 59-94. 26. Warner JJ, Parsons IM. Latissimus dorsi tendon transfer: a comparative analysis of primary and salvage reconstruction of massive, irreparable rotator cuff tears. J Shoulder Elbow Surg 2001;10:514-21. 27. Yian EH, Ramappa AJ, Arneberg O, Gerber C. The Constant score in normal shoulders. J Shoulder Elbow Surg 2005;14: 128-33.