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Subscapularis muscle inervation: An anatomical study and the relationship to surgical subscapularis muscle releases
J. Shoulder Elbow Surg. Volume 4, Number 1, Part 2
SUBSCAPULARIS MUSCLE INERVATION: An anatomical study and the relationship to surgical subscapularis muscle releases. Sergio L.Checchia, Af D., Pedro S. Doneux, ~LD., Marcelo G. ~lartins, J~D., Flamarion S. ~Ieireles, A~LD. Santa Casa Hospital - Medical School / S~loPaulo - Brazil. INTRODUCTION: Extensive subscapularis muscle release and/or lengthening are common procedures on major shoulder reconstructive surgeries, and an e~ensive manipulation in its anterior surface could, a priori, put in risk its enervation, made mostly by two branches from the posterior cord of the brachial ple.was. Surprisingly, very few books of anatomy even describe this nerves, and none of then gives a clear description of their points of entrance in the muscle. So, the purpose of this stud3" is to determine the points of entrance of the neural branches into the subscapularis muscle, and also if this points could be modified according to the position of the arm, from internal (arm at chest), to neutral and external rotation, as the arm is usually held during shoulder surgeries. MATERIAL AND METHODS: Twenty-five shoulders, in 25 very, fresh cadavers have been studied, through an anterior extensive approach, releasing poctoralis major and deltoid attachments from the clavicle and acromion, and the conjoined tendon from the coracoidis. A 1 cm. incision, following the direction of the fibers of the subscapularis was opened, together with the capsule, allowing direct visual~ation of the joint, where a mark was put on the "3 o'clock" position. The branches were dissected and pointed out the entrance at the muscle mass. After that, these distances were measured with the arm in those three positions (I.R, N.R, E.R). When an3' branch was double or even triple, the measures were made in the most lateral one, This paper do not intend to make a description of -the branches variations, already very well done in the literature (Kerr, 1918 - Kato 1989). We also collected authropometric data from the cadavers. The mean age was 61.3 yr., the mean height 1.71 m and the mean weight 69.5 kg.. RESULTS: The results obtained ("student-t test") have showed that the superior branch, in 95% of the cases, enters from 1.09 to 3.99 cm from the joint in ER, from 1.93 to 4.67 cm in N,R, and from 2,41 to 5.35 cm in I.R Thesedifferences were statistically signfieant (chi-square test). The results obtained with the inferior branch measurements showed 0.92 to 5.90 cm in E.R, 1.47 to 6.65 cm in NR, and 1,87 to 7.25 cm in I.R (95% probabilities according to the "student-t test"). The "chi-square test" proved to have no statistical significance between the three positions of the arm. The correlation between anthropometric data, and the distance of the two branches wasn't statistically significant by the "chisquare test", CONCLUSIONS: In conclusion, we found that the branches to the subscapularis muscle can be put in jeopardy during extensive release of this muscle, because sometimes their distance from the glenoidis can be as near as about 1 cm The position of the arm during this procedure can increase this risc, specially to the superior branch with the arm in external rotation. The general size of the cadaver, therefore the size of a potential patient, does not increase the risk of lesion, as one could expect in smaller patients.
Abstracts $91
2
THE USE OF BONE G R A F T I N G IN SHOULDER ARTHROPLASTY: TUBEROSITY SUTURE TECHNIQUE.
Sergio L .Checchia, ~£D., Pedro S. Doneux, ALD., Edgardo P. Martinez, ALD., Carlos ~ S . Garcia, ,?~LD., II~lio P. Leal, ~ D . Santa Casa Hospital - Medical School / S~o Panlo - Brazil.
Sixty - six patients were treated from their severe fracture o~ the proximal third of the humerus by using shoulder arthroplasties. In these kinds of fractures, the conventional shoulder arthroplasty technique has frequently resulted in the release and/or migration of the greater and lesser tuberosities. This common complication leads to unsatisfactory surgical and functional results. During an 18-month radiographic follow-up of these patients the authors found 9 cases with such complications among the 52 patients submitted to this surgical technique. Thus, the authors modified the original technique into one of a stable and reliable suture associated to autollogus bone grafting. The new small modification in the technique was used in fourteen patients demonstrating significant improvement in surgical results. In only one case the suture came loose and this was secondary to deep infection.
3
TREATMENT OF "FROZEN SHOULDER" WITH SUPRASCAPULARIS NERVE BLOCK AND STEROIDS: PRELIMINARY RESULTS. Sergio L .Checchia, i~D., Pedro S.
Doneux, ~LD., Edgardo P. ~,lartinez, Carlos 3~S. Garcia, H~lio P Leal, Santa Casa Hospital - Medical School / S~o Panlo - Brazil. It is known that the "'Frozen Shoulder" ( FS ) is caused by alteration in the autonomic nervous system. The suprascapularis nerve is responsible for the autonomic and sensitive enervation of the shoulder. Sympathetic blocks show good results in the treatment of the sympathetic dy.sfunction, thus a selective block of t h e suprascapularis nerve could be helpful in the treatment of FS, This assumption motivated a prospective study performed on thirteen patients (14 shoulders) who received a 5 or 6 cc, injection of 0.5% bupivacaine with epinephrine on 3-week intervals. Steroids were used as antiinflammatory drugs and in such a way that they would not interfere in the organism's normal metabolism of this chemical. The UCLA system was used for evaluation an follow-up Patients were followed in average for ten months. Results were considered excellent in 4 patients, good in 6 patients, fair in 3 patients and poor in one. The authors conclude that the suprascapularis nerve block is a simple and fast procedure that may be performed in an out-patient setting. Complications rarely occur. It is, therefore, a cost-effective method that relieves pain quickly. Excellent and good results were found in 71.5 % of patients treated.
SUBSCAPULARIS MUSCLE INERVATION: An anatomical study and the relationship to surgical subscapularis muscle releases. Sergio L.Checchia, Af D., Pedro S. Doneux, ~LD., Marcelo G. ~lartins, J~D., Flamarion S. ~Ieireles, A~LD. Santa Casa Hospital - Medical School / S~loPaulo - Brazil. INTRODUCTION: Extensive subscapularis muscle release and/or lengthening are common procedures on major shoulder reconstructive surgeries, and an e~ensive manipulation in its anterior surface could, a priori, put in risk its enervation, made mostly by two branches from the posterior cord of the brachial ple.was. Surprisingly, very few books of anatomy even describe this nerves, and none of then gives a clear description of their points of entrance in the muscle. So, the purpose of this stud3" is to determine the points of entrance of the neural branches into the subscapularis muscle, and also if this points could be modified according to the position of the arm, from internal (arm at chest), to neutral and external rotation, as the arm is usually held during shoulder surgeries. MATERIAL AND METHODS: Twenty-five shoulders, in 25 very, fresh cadavers have been studied, through an anterior extensive approach, releasing poctoralis major and deltoid attachments from the clavicle and acromion, and the conjoined tendon from the coracoidis. A 1 cm. incision, following the direction of the fibers of the subscapularis was opened, together with the capsule, allowing direct visual~ation of the joint, where a mark was put on the "3 o'clock" position. The branches were dissected and pointed out the entrance at the muscle mass. After that, these distances were measured with the arm in those three positions (I.R, N.R, E.R). When an3' branch was double or even triple, the measures were made in the most lateral one, This paper do not intend to make a description of -the branches variations, already very well done in the literature (Kerr, 1918 - Kato 1989). We also collected authropometric data from the cadavers. The mean age was 61.3 yr., the mean height 1.71 m and the mean weight 69.5 kg.. RESULTS: The results obtained ("student-t test") have showed that the superior branch, in 95% of the cases, enters from 1.09 to 3.99 cm from the joint in ER, from 1.93 to 4.67 cm in N,R, and from 2,41 to 5.35 cm in I.R Thesedifferences were statistically signfieant (chi-square test). The results obtained with the inferior branch measurements showed 0.92 to 5.90 cm in E.R, 1.47 to 6.65 cm in NR, and 1,87 to 7.25 cm in I.R (95% probabilities according to the "student-t test"). The "chi-square test" proved to have no statistical significance between the three positions of the arm. The correlation between anthropometric data, and the distance of the two branches wasn't statistically significant by the "chisquare test", CONCLUSIONS: In conclusion, we found that the branches to the subscapularis muscle can be put in jeopardy during extensive release of this muscle, because sometimes their distance from the glenoidis can be as near as about 1 cm The position of the arm during this procedure can increase this risc, specially to the superior branch with the arm in external rotation. The general size of the cadaver, therefore the size of a potential patient, does not increase the risk of lesion, as one could expect in smaller patients.
Abstracts $91
2
THE USE OF BONE G R A F T I N G IN SHOULDER ARTHROPLASTY: TUBEROSITY SUTURE TECHNIQUE.
Sergio L .Checchia, ~£D., Pedro S. Doneux, ALD., Edgardo P. Martinez, ALD., Carlos ~ S . Garcia, ,?~LD., II~lio P. Leal, ~ D . Santa Casa Hospital - Medical School / S~o Panlo - Brazil.
Sixty - six patients were treated from their severe fracture o~ the proximal third of the humerus by using shoulder arthroplasties. In these kinds of fractures, the conventional shoulder arthroplasty technique has frequently resulted in the release and/or migration of the greater and lesser tuberosities. This common complication leads to unsatisfactory surgical and functional results. During an 18-month radiographic follow-up of these patients the authors found 9 cases with such complications among the 52 patients submitted to this surgical technique. Thus, the authors modified the original technique into one of a stable and reliable suture associated to autollogus bone grafting. The new small modification in the technique was used in fourteen patients demonstrating significant improvement in surgical results. In only one case the suture came loose and this was secondary to deep infection.
3
TREATMENT OF "FROZEN SHOULDER" WITH SUPRASCAPULARIS NERVE BLOCK AND STEROIDS: PRELIMINARY RESULTS. Sergio L .Checchia, i~D., Pedro S.
Doneux, ~LD., Edgardo P. ~,lartinez, Carlos 3~S. Garcia, H~lio P Leal, Santa Casa Hospital - Medical School / S~o Panlo - Brazil. It is known that the "'Frozen Shoulder" ( FS ) is caused by alteration in the autonomic nervous system. The suprascapularis nerve is responsible for the autonomic and sensitive enervation of the shoulder. Sympathetic blocks show good results in the treatment of the sympathetic dy.sfunction, thus a selective block of t h e suprascapularis nerve could be helpful in the treatment of FS, This assumption motivated a prospective study performed on thirteen patients (14 shoulders) who received a 5 or 6 cc, injection of 0.5% bupivacaine with epinephrine on 3-week intervals. Steroids were used as antiinflammatory drugs and in such a way that they would not interfere in the organism's normal metabolism of this chemical. The UCLA system was used for evaluation an follow-up Patients were followed in average for ten months. Results were considered excellent in 4 patients, good in 6 patients, fair in 3 patients and poor in one. The authors conclude that the suprascapularis nerve block is a simple and fast procedure that may be performed in an out-patient setting. Complications rarely occur. It is, therefore, a cost-effective method that relieves pain quickly. Excellent and good results were found in 71.5 % of patients treated.