ANSA PECTORALIS – ANATOMY AND APPLIED ASPECTS

Ansa pectoralis is the loop of communication between medial and lateral pectoral nerves, seen anterior to the second part of axillary artery. It carries C7 ?bres from the lateral cord to the medial pectoral nerve and supplies sternocostal part of pectoralis major muscle. Its damage can cause weakness of the sternocostal part of pectoralis major muscle. Section of the ansa pectoralis is done as a treatment modality to reduce spasm of pectoralis major after strokes. It is also used as nerve graft. There are only few articles which describe the anatomy of Ansa pectoralis. We conducted a dissection study in 36 pectoral regions of embalmed human cadavers to ?nd out the number, location, formation and branches of Ansa pectoralis. During dissection of the pectoral region, the formation of Ansa was seen to be of four different types. 72.2%(26 out of 36) was either between inferior or deep branch of lateral pectoral nerve and medial pectoral nerve or between the inferior lateral pectoral nerve and medial pectoral nerve (type A). In 6 cases (16.7%) it was between trunk of the lateral pectoral nerve and medial Pectoral nerve (type B). In 3 cases (8.3%), it was arising from lateral cord itself (Type C). In one case (2.7%) it was found to be arising from trunk and inferior branch of lateral pectoral nerve (Type D). The communicating loop was on the axillary artery in about 52.8% percentage of specimens, distal and plastered to the deep surface of pectoralis minor muscle in the 30.5% and multiple in 16.7%. The anatomy of Ansa pectoralis shows many variations. These are important while planning surgeries in pectoral region like breast augmentation, pectoral nerve blocks and harvesting pectoral nerve grafts.

To evaluate analgesic efficacy of dexamethasone as an adjuvant to ropivacaine in pectoral nerve block: A prospective randomized control study.

Background: Pectoral nerve (Pecs) block is an effective component of multimodal analgesic regimens for breast surgeries. In present study we compared analgesic effect of dexamethasone 8 mg as an adjuvant to 0.25% ropivacaine versus 0.25% ropivacaine alone in pectoral nerve block. Methods: The study was conducted in a randomized manner on 60 female patients of American Society of Anesthesiologists (ASA) Grade I and II, aged between 18 to 65 years, scheduled to undergo modified radical mastectomy under general anesthesia (GA). The patients were randomly allocated into 2 groups of 30 patients each. Group A received ultrasound (US)-guided Pecs block with 30 ml of 0.25% ropivacaine and 10 ml normal saline (total volume 40 ml) and Group B received with 30 ml of 0.25% ropivacaine and 8 mg dexamethasone in and 10 ml normal saline (total volume 40 ml). Post-operatively visual analogue score (VAS), duration of analgesia and total analgesic consumption was noted. Student t-test, Mann Whitney U test and Chi-square test were used for statistical analysis. Results: VAS were persistently low for first 4 hours in group B and for first 9 hours in group A (p value < 0.001 at some intervals). The mean duration of analgesia was prolonged in group B as compared to group A (612.33 ± 41.77 min in Group B and 307.70 ± 22.37min in group A) (p <0.001). Total analgesic consumption in first 24 hours post-operatively was also statistically lower in Group B (97.50± 34.96 mg) as compared to group A (177.50± 36.76) (p<0.001). No patient under study reported any adverse effects. Conclusion: Addition of 8 mg dexamethasone as adjuvant to 0.25% ropivacaine for pectoral nerve block increases the duration of analgesia and significantly reduces the amount of analgesic requirement in first 24 hours postoperatively without any significant adverse effects.

Efficacy of ultrasound-guided pectoral nerve block versus thoracic paravertebral block for postoperative analgesia after radical mastectomy / 临床麻醉学杂志

Objective To compare the efficacy and safety of ultrasound guided pectoral nerves Ⅱ (Pecs Ⅱ) block with thoracic paravertebral nerve (TPVN) block for postoperative analgesia after modified radical mastectomy.Methods Eighty female patients scheduled for radical mastectomy,aged 40-65 years,ASA physical status Ⅰ or Ⅱ,were randomly divided into 2 groups using a random number table method (n =40 each):the patients in group T received TPVN block,whereas the pa tients in group P received Pecs Ⅱ block.Both the groups received 0.5 ％ ropivacaine 25 ml.The blocks were performed under all aseptic precautions in the preoperating room 30 min before surgery.The total number of dermatomes that had less pain to pin prick compared with opposite side were not ed.All patients were observed for 30 min after performing the block.The patients were received patient-controlled intravenous analgesia (PCIA).The duration of analgesia and total analgesic consumption in 24 h after surgery were recorded.Adverse effects were recorded between the two groups.Results The duration of analgesia in group P was significantly prolonged than group T [(326.5± 47.8) min vs (201.4±34.5) min,P＜0.01].The 24 h sufentanil consumption were also decreased in group P [(6.9±1.2) μg vs (10.7±1.9) μg,P＜0.01].T2 dermatomal spread were significantly increased in group P [35 (87.6％) cases vs 9 (22.5％) cases,P＜0.05].No complication was recor ded.Conclusion Ultrasound-guided Pecs Ⅱ block and TPVN provided safe and effective anesthesia in patients undergoing modified radical mastectomy,but the effect of Pecs Ⅱ block were more satisfied and per sistent.

Neurotization from Two Medial Pectoral Nerves to Musculocutaneous Nerve in a Pediatric Brachial Plexus Injury

Traumatic brachial plexus injuries can be devastating, causing partial to total denervation of the muscles of the upper extremities. Surgical reconstruction can restore motor and/or sensory function following nerve injuries. Direct nerve-to-nerve transfers can provide a closer nerve source to the target muscle, thereby enhancing the quality and rate of recovery. Restoration of elbow flexion is the primary goal for patients with brachial plexus injuries. A 4-year-old right-hand-dominant male sustained a fracture of the left scapula in a car accident. He was treated conservatively. After the accident, he presented with motor weakness of the left upper extremity. Shoulder abduction was grade 3 and elbow flexor was grade 0. Hand function was intact. Nerve conduction studies and an electromyogram were performed, which revealed left lateral and posterior cord brachial plexopathy with axonotmesis. He was admitted to Rehabilitation Medicine and treated. However, marked neurological dysfunction in the left upper extremity was still observed. Six months after trauma, under general anesthesia with the patient in the supine position, the brachial plexus was explored through infraclavicular and supraclavicular incisions. Each terminal branch was confirmed by electrophysiology. Avulsion of the C5 roots and absence of usable stump proximally were confirmed intraoperatively. Under a microscope, neurotization from the musculocutaneous nerve to two medial pectoral nerves was performed with nylon 8-0. Physical treatment and electrostimulation started 2 weeks postoperatively. At a 3-month postoperative visit, evidence of reinnervation of the elbow flexors was observed. At his last follow-up, 2 years following trauma, the patient had recovered Medical Research Council (MRC) grade 4+ elbow flexors. We propose that neurotization from medial pectoral nerves to musculocutaneous nerve can be used successfully to restore elbow flexion in patients with brachial plexus injuries.

Clinical Significance of Scanlon's Procedure in a Modified Radical Mastectomy for Patients with Infiltrating Breast Cancer

PURPOSE: Modified radical mastectomy is the most commonly performed operative treatment because of extensive microcalcifications, multicentric tumors, early pregnancy, and patient preference, despite of the eligibility of many women for breast-conserving surgery. Various modifications of this operation have been described, including preservation of the pectoralis minor, resection of the pectoralis minor, and division of the origin of the pectoralis minor. The purpose of this study was to identify the indications of Scanlon's technique by evaluating the benefit of complete axillary dissection and the cosmetic results of chest walls in patients who had undergone a modified radical mastectomy (MRM) for breast cancer. METHODS: In fifty nine patients who had undergone MRM for infiltrating breast cancer from January 1992 to December 1997 and performed follow-up study of CT of chest walls, we examined operative techniques, dissected & involved axillary lymph nodes (ALNs) retrospectively and atrophy of pectoralis muscles by clinical examination and CT findings of chest walls. RESULTS: We analyzed all the results of aforementioned study, based on various operative techniques. The largest groups were Auchincloss of 63.6% in stage IIA, Scanlon of 50% in stage IIB and Patey of 28.6% in stage IIIA. The mean numbers of harvested ALNs were 20.4 in Scanlon, 20 in Patey and 15 in Auchincloss. The largest groups were Auchincloss of 77.3% in the harvested ALNs of 10-19, Scanlon of 40% in the harvested ALNs of 20-29 and Patey of 14.3% in the harvested ALNs of 30-39. The mean numbers of involved ALNs were 4.4 in Patey, 2.6 in Scanlon and 0.9 in Auchincloss. The largest groups were Auchincloss of 63.6% in the non-involved ALNs, Auchincloss of 31.8% in the involved ALNs of 1-3, Scanlon of 20% in the involved ALNs of 4-9 and Patey of 28.6% in the involved ALNs of 10 or more. Through the clinical examinations and CT studies of chest wall, such changes of chest walls were found, as suggestive of injury of medial pectoral nerve of 2 cases (9.1%) and of lateral pectoral nerve of 1 case (4.5%) inAuchincloss, of injury of medial pectoral nerve of 1 case (3.3%) in Scanlon and of injuries of medial pectoral nerve of 3 cases (42.9%) and of lateral pectoral nerve of 1 case (14.3%) in Patey. Postoperative complications were arm lymphedema of 1 case in each technique and anemia of 4 cases (13.3%) in Scanlon. CONCLUSION: We conclude that in the MRM for patients with resectable breast cancer, Scanlon's technique is superior to Auchincloss or Patey in preventing axillary recurrence and atrophies of pectoralis muscles by successful complete axillary dissection with preservation of medial and lateral pectoral nerve in cases of more advanced stage over stage IIB with involved ALNs of one to nine. However Patey's technique seems to be necessary in cases of metastasis of the interpectoral node or the subclavicular node regardless of poor results of cosmesis.

Chest Well Muscle Changes after A Mestectomy Findings of Chest CT / 한국유방암학회지

BACKGROUND: Chest CT after a mastectomy in breast cancer patients is usually performed to detect recurrence or metastasis. It is essential for surgeons an radiologists to know the appearance of the chest wall in a postmastectomy state. Especially, muscle atrophies of the chest wall, such as that of the pectoralis major muscle, indicate whether the modified radical mastectomy (MRM) was properly performed or not. MATERIALS AND METHODS: We performed a retrospective analysis of chest wall changes in mastectomy patients with follow-up chest CT finding to evaluate the results of MRMs. The medical records and CT findings of chest wall atrophy for a total of 38 patients who were treated at Kangnam St. Mary's Hospital, the Catholic University of Korea, were reviewed. The mean age was 58.3 years, and the interval between operation and follow-up CT was 6.6 years. The operations performed were a radical mastectomy (RM) in 3 patients and a MRM in 35 patients: Petey in 28 patients, Auchincloss in 6 patients, and Scanlon in 1 patient. RESULTS: In the RM, muscle atrophies were noted at the m, subscapularis in 3 patients (100%), the m. serratus anterior in 2 patients (66.7%), and the m. lattisimus dorsi in 1 patient (33.3%). In MRM, the Patey and Auchincloss operations showed m. pectoralis major atrophies in 22 patients (78.8%) and 5 patients (83.3%) respectively. Additionally m. pectoralis minor atrophy was noted in all 6 patients (100%) who underwent the Auchincloss operation. However. there was no muscle atrophy in patients who received Scanlon operation. CONCLUSIONS: These results suggest that lateral pectoral nerve injury is the main cause of m. pectoralis major atrophy in a MRM. The Scanlon operation which preserves the serve by dividing the pectoralis minor m. at its origin is a suitable operation for chest-wall muscle preservation. We hope that by the future study, we can confirm the best way of preventing chest-wall muscle atrophy in MRMs.

Chest Wall Muscle Changes after a Mastectomy: Findings of Chest CT

BACKGROUND: Chest CT after a mastectomy in breast cancer patients is usually performed to detect recurrence or metastasis. It is essential for surgeons and radiologists to know the appearance of the chest wall in a postmastectomy state. Especially, muscle atrophies of the chest wall, such as that of the pectoralis major muscle, indicate whether modified radical mastectomy (MRM) was properly performed or not. METHODS: We performed a retrospective analysis of chest wall changes in mastectomy patients with follow-up chest CT findings to evaluate the results of MRMs. The medical records and CT findings of chest wall atrophy for a total 38 patients who were treated at Kangnam St. Mary's Hospital, the Catholic University of Korea, were reviewed. The mean age was 58.3 yeras, and the interval between operation and follow-up CT was 6.6 years. The operations performed were a radical mastectomy (RM) in 3 patients and a MRM in 35 patients: Patey in 28 patients, Auchincloss in 6 patients, and Scanlon in 1 patient. RESULTS: In the RM, muslce atrophies were noted at the m. subscapularis in 3 patients (100 %), the m. serratus anterior in 2 patients (66.7%) and the m. lattisimus dorsi in 1 patient (33.3%). In MRM, the Patey and Auchincloss operations showed m. pectoralis major atrophies in 22 patients (78.8%) and 5 patients (83.3%) respectively. Additionally m. pectoralis minor atrophy was noted in all 6 patients (100%) who underwent the Auchincloss operation. However, there was no muscle atrophy in patients who received scanlon operation. CONCLUSIONS: These results suggests that lateral pectoral nerve injury is the main cause of m. pectoralis major atrophy in MRM. The scanlon operation which preserves the nerve by dividing of pectoralis minor m. at its origin is a suitable operation for chest-wall muscle preservation. We hope that by the future study, we can confirm the best way of preventing chest-wall muscle atrophy in MRMs.

Functional nerve preserving modified radical mastectomy / 中国普通外科杂志

Objective To investigate the methods and clinical significances of preserving the pectoral nerve(PN) and intercosto-brachial nerve(IBN) in modified radical mastectomy. Methods Eighty-seven patients suffering from breast cancer in stage Ⅰ and Ⅱ were randomly divided into 2 groups. Transpectoral anterior approach was used on patients in group A(n=52),with axillary lymph node dissection, preservation of the pectoralis minor muscles, PNS and IBNS. Patients in group B(n=35) were operated on through transpectoral posterior approach, with dissection of pectoralis minor muscles, sections of PNS and IBNS. Results No case in group A and 28 cases(80%) in group B suffered from postoperative atrophy of pectoralis major muscles(P