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Official Description

Division of sternocleidomastoid for torticollis, open operation; without cast application

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The procedure described by CPT® Code 21720 involves the open division of the sternocleidomastoid muscle, which is a key muscle in the neck that plays a significant role in head movement. This surgical intervention is primarily indicated for the treatment of torticollis, a condition characterized by an abnormal, asymmetrical head or neck position. Torticollis can be congenital, meaning it is present at birth, or acquired, developing later in life due to various factors. The open division aims to relieve the tension in the sternocleidomastoid muscle, thereby allowing for improved head positioning and function. The procedure entails making an incision above the medial aspect of the clavicle to access the muscle tendons, which are then carefully manipulated to alleviate the contracted state. Depending on the severity of the condition, the surgeon may perform either a unipolar or bipolar release of the muscle. The unipolar release involves addressing the muscle at one end, while the bipolar release addresses both ends of the muscle, providing a more comprehensive correction for severe cases. This procedure is performed without the application of a cast, which distinguishes it from similar procedures that may require immobilization for optimal recovery.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The open division of the sternocleidomastoid muscle, as described by CPT® Code 21720, is indicated for the following conditions:

  • Congenital Muscular Torticollis - A condition present at birth where the neck muscles are shortened, leading to an abnormal head position.
  • Acquired Torticollis - A condition that develops later in life, potentially due to muscle spasms, injury, or other underlying issues affecting neck mobility.

2. Procedure

The procedure for the open division of the sternocleidomastoid muscle involves several critical steps to ensure effective treatment of torticollis:

  • Step 1: An incision is made above the medial aspect of the clavicle to access the sternocleidomastoid muscle. This incision allows the surgeon to expose the tendons of the muscle that attach to the sternum and clavicle.
  • Step 2: The tendon sheaths are incised longitudinally, which facilitates the exposure of the muscle fibers. The inferior ends of the tendons are then partially resected to relieve tension.
  • Step 3: The patient's head is turned toward the affected side, and the chin is depressed to further assist in the surgical approach. This positioning helps in visualizing the contracted muscle and surrounding structures.
  • Step 4: The platysma muscle and adjacent fascia are divided to gain better access to the sternocleidomastoid muscle. The surgical wound is then explored for any remaining bands of contracted muscle or fascia.
  • Step 5: Any identified bands of contracted sternocleidomastoid muscle or fascia are carefully divided to release the tension and restore normal head positioning.
  • Step 6: In cases of severe torticollis, a bipolar release is performed. This involves an additional incision behind the ear to release the sternocleidomastoid muscle just distal to the tip of the mastoid process, followed by the previously described release at the sternum and clavicle.

3. Post-Procedure

After the completion of the procedure, the patient may be placed in a cervical collar to support the neck and maintain proper alignment of the head. Although the specific procedure described by CPT® Code 21720 does not involve the application of a cast, it is important to note that in cases where a cast is applied, it would consist of an upper body cast with metal rods on either side of the neck, attached to a head immobilizer that encircles the forehead and upper skull. Post-operative care includes monitoring for any complications, ensuring proper healing, and providing instructions for rehabilitation exercises to restore neck mobility and strength.

Short Descr REVISION OF NECK MUSCLE
Medium Descr DIVISION STERNOCLEIDOMASTOID OPEN W/O CAST
Long Descr Division of sternocleidomastoid for torticollis, open operation; without cast application
Status Code Active Code
Global Days 090 - Major Surgery
PC/TC Indicator (26, TC) 0 - Physician Service Code
Multiple Procedures (51) 2 - Standard payment adjustment rules for multiple procedures apply.
Bilateral Surgery (50) 0 - 150% payment adjustment for bilateral procedures does NOT apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 2 - Payment restriction for assistants at surgery does not apply to this procedure...
Co-Surgeons (62) 0 - Co-surgeons not permitted for this procedure.
Team Surgery (66) 0 - Team surgeons not permitted for this procedure.
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Hospital Part B services paid through a comprehensive APC
ASC Payment Indicator Surgical procedure on ASC list in CY 2007; payment based on OPPS relative payment weight.
Type of Service (TOS) 2 - Surgery
Berenson-Eggers TOS (BETOS) P3D - Major procedure, orthopedic - other
MUE 1
CCS Clinical Classification 160 - Other therapeutic procedures on muscles and tendons
LT Left side (used to identify procedures performed on the left side of the body)
51 Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d).
58 Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period: it may be necessary to indicate that the performance of a procedure or service during the postoperative period was: (a) planned or anticipated (staged); (b) more extensive than the original procedure; or (c) for therapy following a surgical procedure. this circumstance may be reported by adding modifier 58 to the staged or related procedure. note: for treatment of a problem that requires a return to the operating/procedure room (eg, unanticipated clinical condition), see modifier 78.
78 Unplanned return to the operating/procedure room by the same physician or other qualified health care professional following initial procedure for a related procedure during the postoperative period: it may be necessary to indicate that another procedure was performed during the postoperative period of the initial procedure (unplanned procedure following initial procedure). when this procedure is related to the first, and requires the use of an operating/procedure room, it may be reported by adding modifier 78 to the related procedure. (for repeat procedures, see modifier 76.)
80 Assistant surgeon: surgical assistant services may be identified by adding modifier 80 to the usual procedure number(s).
82 Assistant surgeon (when qualified resident surgeon not available): the unavailability of a qualified resident surgeon is a prerequisite for use of modifier 82 appended to the usual procedure code number(s).
AS Physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery
GC This service has been performed in part by a resident under the direction of a teaching physician
RT Right side (used to identify procedures performed on the right side of the body)
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