<prompt> A nerve injured in radical neck dissection leads to loss of sensation in medial side of the arm, nerve injured is?Long thoracic nerveThoracodorsal nerveDorsal scapular nerveMedial cutaneous nerve of arm  <response>: ANSWER: D Medial cutaneous nerve of armREF: Schwartz 9th ed chapter 18, Bailey 25th ed page 733, Mastery of Surgery, Volume 1 edited by Josef E. Fischer, Kirby I. Bland, Mark P. Callery 5th ed Vol 1 page 323Virtually any part of brachial plexus can be injured in RND. Read following lines of Grays anatomy.The medial cutaneous nerve of the arm is the smallest and most medial branch of the brachial plexus, and arises from the medial cord C8, Tl. It crosses the axilla, either anterior or posterior to the axillary vein, then passes medial to the axillary vein, communicates with the intercostobrachial nerve, and descends medial to the brachial artery and basilic vein. It pierces the deep fascia at the midpoint of the upper arm to supply the skin over the medial aspect of the distal third of the upper arm. Grays anatomy 40th ed chapter 46Safety or Holy layer; the layer of prevertebral fascia that covers the brachial plexus and phrenic nerve. It is advisable to stay superficial to this layer in order to avoid damage to these vital structures Ref: Step by step Neck dissection Dr Chintamani page 5MASTERY OF SURGERY 5TH ED VOL 1 TABLE 6 PAGE 323TYPES OF NECK DISSECTIONSDissectionLymph Node Levels RemovedNon nodal Structures RemovedIndicationsComprehensive neck dissectionsRadical Classical Crile RNDLevels I-VSpinal accessory nerve SAN Internal jugular vein IJV Sternocleidomastoid muscle SCMSubmandibular glandNr neck for SCC when SAN is involvedMRND type 1Levels I-VPreserves SANN neck for SCC when SAN is free most commonly used for SCC of upper aerodigestive tractMRND type 2Levels I-VPreserves SAN SCMN neck for SCC when LA7 is involved but SAN is freeMRND type 3Levels I-VPreserves SAN, IJV SCMMost commonly used for metastatic Ca of thyroidSelective neck dissectionsSupraomohyoidLevel I- IIIPreserves SAN, IJV SCMN-ve neck SCC of oral cavity and oropharynx N-ve neck malignant melanoma anterior to earExtendedsupraomohyoidLevel I- IVPreserves SAN, IJV SCMN-ve neck SCC of lateral tongueLateral NDLevel II- IVPreserves SAN, IJV SCMN-ve neck SCC of Larynd HypopharynxPosterioLateral NDLevel II- V,Suboccipital,RetroauricularPreserves SAN, IJV SCMN-ve neck malignantmelanoma posterior to earNote:Structure preserved in RND: ICA, EC A may be sacrificed, Brachial plexus, Hypoglossal nerve, Vagus nerve, Phrenic nerve, Facial nerve cervical and marginal mandibular branches, Sympathetic trunkCommonest incisions in RND:Criles incision modified Y incisionMacfees incision double horizontal incision in irradiated neck.The main disability that follows the RND is weakness and drooping of the shoulder due to paralysis of the trapezius muscle as a consequence of excision of the spinal accessory nerve. 