Download Rajiv Gandhi University of Health Sciences Karnataka, Bangalore

Rajiv Gandhi University of Health Sciences
Karnataka, Bangalore
Annexure 2
Proforma for registration of subjects for dissertation
1. Name of the candidate and Address:
Thuslima M.
Postgraduate student, Department of Anatomy
St.John’s Medical College, Bangalore-560 034.
Residential address:
No.2,Vallalar Street, Kosapalayam, Puducherry-605013.
2. Name of the institution: St.John’s Medical College,
Bangalore - 560 034.
3. Course of the study and subject: M.D (Anatomy)
4. Date of admission: 15th MAY 2012
5. Title of the topic: “Surgical Anatomy of Axillary Nerve”.
6.1 Need for the study:
The Axillary nerve is one of the terminal branches of posterior cord of brachial plexus and
contains fibres from c5, c6, ventral rami. It innervates teres minor and deltoid muscles,the
skin over the shoulder and the gleno-humeral joint .
Injuries to the Axillary nerve make up 6% of all brachial plexus injuries[1] .
Injections in and about the shoulder complex are performed routinely for the purposes of
vaccination, IM medication administration, deltoid trigger-point injections, and intra-articular
and bursal steroid injections. Although such injections are considered routine office
procedures, there is increased risk of injury to the subdeltoid/subacromial bursa, anterior
branch of the axillary nerve and the radial nerve if performed incorrectly, which reflects the
lack of awareness of the anatomical position of these structures in and near this muscle [2].
The nerve injury may occur together with shoulder dislocation and rotator cuff
tear,comprising the ‘unhappy triad’ of shoulder joint[6].
Knowledge of the precise relationship of the branches of the axillary nerve, its relationship to
the shoulder capsule and its common variations within deltoid muscle, provides
morphometric data that could be applied during surgical procedures over shoulder, and
reduce the incidence of iatrogenic nerve damage.
6.2 AIMS AND OBJECTIVES:
The aim of this study is to determine the distribution patterns of anterior and posterior
branches of axillary nerve and to determine the exact anatomical location of the axillary
nerve in relation to surface landmarks, specifically the acromion process and the deltoid
tuberosity.
The specific objectives are
To analyse the following measurements:
1. To determine the diameter of the trunk of Axillary nerve on right and left side
2. To determine diameter of Anterior division of the nerve on right and left side
3. To determine diameter of Posterior division of the nerve on right and left side
4. To determine the distance of the nerve from the acromian process on right and left
side
5. To determine the distance of the nerve from the Deltoid tuberosity on the right and
left side
6. To determine the presence or absence of the pseudoganglion in the posterior division
of the axillary nerve.
7. To determine the number of branches given off by the anterior division of the axillary
nerve on the left and right side
8. To determine the number of branches given off by the posterior division of the
axillary nerve on the right and left side.
9. To determine the percentage of cases where the posterior circumflex humeral artery
accompanies the posterior division of the axillary nerve.
10. To determine the caliber of the posterior circumflex humeral artery.
6.3 REVIEW OF LITERATURE:
Various authors have studied the distribution patterns of axillary nerve.
Marios Loukas et al studied the anatomic variations of the axillary nerve within the
deltoid muscle, and found that, In 65% of cases, the axillary nerve split into two branches
(anterior and posterior) within the quadrangular space, and in the remaining 35% split within
the deltoid muscle. The posterior branch of the deltoid muscle irrespectively of origin gave
off a branch to the teres minor and the superior lateral brachial cutaneous nerve in 100% of
cases. The branch to the posterior part of the deltoid muscle was present in 90% of cases, and
the branch to the middle part of the deltoid was present in 38% of cases. The anterior branch
of the deltoid muscle provided a branch to the joint capsule, a branch to the anterior part of
the deltoid muscle and the middle part of the deltoid in 100% of cases. In 18% of the cases,
the anterior branch of the axillary nerve provided a branch to the posterior part of the deltoid
muscle. The middle part of the deltoid muscle received dual innervation in 38% of cases and
the posterior part of the deltoid muscle in 8% of the cases [1].
An evidence based protocol for safe vaccine administration into the deltoid muscle was
presented by Ian F Cook, which was developed using anthropometric measurements of the
surface anatomical landmarks in adults who regularly receive intramuscular injection of
vaccines into the deltoid muscle (adults ≥65 y old) and mapping the position of structures
potentially injured by injection observed in ultra sonographic and cadaveric studies. The
midpoint of the muscle (midway between the acromion and the deltoid tuberosity) with the
arm abducted to 60° is a safe site for injection [2].
Ozgur Cetik et al, studied the distance of the axillary nerve from the acromion and its
relation to arm length ,and identified a safe area above the axillary nerve which is
quadrangular in shape, with the length of the lateral edges being dependent on the individual's
arm length. The axillary nerve was not found to lie at a constant distance from the acromion
at every point along its course [3].
Kontakis GM et al studied the position of axillary nerve within deltoid muscle and found
that, the vertical distances from the upper deltoid border to the nerve in 17 of 67 cadavers was
less than 4 cm in both shoulders. The minimal distance, measured from the mid-middle
portion of the deltoid to the axillary nerve, was 2 cm. There was a significant negative
correlation between the deltoid ratio (width/length) and the vertical distance, measured in all
examined sites. The shorter the deltoid length the greater the danger of damaging the nerve in
the short distance during surgical splitting of the muscle [4].
In a study done by Nakatani T et al , the course of the axillary nerve was determined from
the skin covering the deltoid muscle in order to safely administer intramuscular injection into
the muscle without injuring the nerve. In this study, the course of the axillary nerve projected
on the skin covering the deltoid muscle was the transverse line situated at the lower 1/3
between the supero-lateral margin of the acromion and the antero-posterior axillary line. The
intramuscular injection in the deltoid muscle can be safely performed using these landmarks
without risking injury to the axillary nerve [5].
7 MATERIAL AND METHODS:
7.1 SOURCE OF DATA: Thirty adult cadavers from the department of Anatomy, St John’s
Medical College, Bangalore.
SAMPLE SIZE: The sample size was calculated using n Master software. The values for
sample size estimation were obtained from literature and a pilot study conducted at the
Department of Anatomy at St.John’s
Medical
College. The standard deviation of the
distance of the nerve from acromian was 0.6. The sample mean (from the pilot study) and
population mean were 5.7 and 6 respectively. The alpha error and power were set at 5% and
80%.The required sample size was calculated to be thirty.
7.2 INCLUSION CRITERIA: Specimens without any grossly evident shoulder pathologies
or surgical procedures.
7.3 EXCLUSION CRITERIA: Specimens with grossly evident shoulder pathologies or
surgical procedures.
7.4 STUDY DESIGN: Analytical study- cross sectional type.
7.5 Protocol of the Procedure
The cadavers will be dissected and the parameters mentioned in the objective will be
measured with the help of digital vernier callipers accurate to 0.01mm. The values so
measured will be analysed using SPSS 16. Paired sample t test will be used to compare
means. A P value of ≤ 0.05 will be considered significant.
7.6 Does the study require any investigations or interventions to be
conducted on patients or other human or animals? If so please describe
briefly
No interventions or investigations will be done.
7.7 Has ethical clearance obtained from your institution in case of 7.3?
Ethical clearance has been obtained.
8 REFERENCES:
1) Marios Loukas, Joanna Grabska, Shane Tubbs, Nihal Apaydin, Robert Jordan. Mapping
the axillary nerve within the deltoid muscle. Surgical and Radiologic Anatomy. 2009;
31(3):43-47.
2) Ian F Cook. An evidence based protocol for the prevention of upper arm injury related to
vaccine administration. Human Vaccines. 2011; 7(8): 845-84.
3) Cetik O, Uslu M, Acar HI, Comert A, Tekdemir I, Cift H. Is there a safe area
for the axillary nerve in the deltoid muscle? Journal of Bone and Joint Surgery. 2006; 88-A.
4) Kontakis GM, Steriopoulos K, Damilakis J, Michalodimitraskis E. The position of the
axillary nerve in the deltoid muscle. Acta Orthop Scand.1999; 70(1): 9-11.
5) Nakatani T, Kitagawa A, Kitayama Y, Tanaka A, Yamazaki M, Konya C, Tanaka S. The
course of the axillary nerve projected on the skin covering the deltoid muscle of a cadaver for
safely administering intramuscular injection in the deltoid muscle. Journal of the Tsuruma
Health Science Society. 2003; 27(1): 33-37.
6) Nihal Apaydin, Shane Tubbs, Marios Loukas, Fabrice Duparc. Review of the surgical
anatomy of the axillary nerve and the anatomic basis of its iatrogenic and traumatic injury.
Surgical and Radiologic Anatomy.2010; 32(3): 193-201.
9. Signature of candidate
10. Remarks of Guide:
11. Name and designation
11.1 Guide : Dr. Roopa Ravindranath
Professor and Head of Department,
Department of Anatomy,
St.John’s Medical college.
11.2 Signature:
11.3 Co-guide: Dr.Lakshmi T.A,
Lecturer,
Department of Anatomy,
St.John’s Medical college.
11.4 Signature:
11.5 Head of the Department: Dr. Roopa Ravindranath
11.6 Signature
12.1 Remarks of the chairman & Principal;
12.2 Signature