The shoulder is one of the fastest growing areas in extremity surgery due to the explosion of techniques and technology that has occurred over the past two decades. As shoulder case numbers in the inpatient and outpatient setting have steadily increased, the importance of reproducible positioning on workflow has been increasingly recognized. Surgeons and OR staff alike have found that effective positioning of shoulder cases has an important influence on the safety and outcome of the case, as well as OR efficiency and room turnover.
For the majority of shoulder operations, the surgeon must choose from basically two positions that afford access to the shoulder: lateral decubitus position or beach chair position. There are advantages and disadvantages for each position in certain applications. Consequently, the type of procedure and surgeon preference dictates which will be appropriate for a given case. The lateral decubitous position requires a traction setup to be applied to the bed, producing static traction for arm control during the case. This position is primarily used for arthroscopic cases, particularly shoulder instability cases. Proponents of this position cite improved blood pressure control and improved access during instability cases as advantages.
The beach chair position allows the surgeon to perform arthroscopic, open, or hybrid procedures easily with the patient’s anatomy in a more typical position. This is the position of choice for fractures, as it affords good X-ray exposure and ability to reduce fragments in anatomic position. Arthroplasty, which requires free arm mobility, glenoid access, and a potentially extensile surgical approach, is performed in this position as well. Additional advantages of the beach chair position include circumferential access to the shoulder and minimizing the chance of traction neuropraxia to the upper extremity.
Historically, placing a patient in the beach chair position has been a source of delayed room turnover and anxiety for OR personnel and surgeons, due to the requirement of specialized knowledge and experience to achieve satisfactory results. In order to safely position a person in beach chair position, a PA, resident, fellow, or attending level doctor must personally supervise the positioning event after induction of anesthesia. The provider responsible for positioning must have detailed knowledge of the actual surgical procedure, exposure requirements, mobility limitations of the affected joint, fluoroscopic or intraoperative x-ray exposure needs, working knowledge of spine anatomy and alignment, understanding of airway control and positioning, understanding of IV and indwelling block locations, as well as concern over normal compression points and peripheral nerve anatomy. Positioning may require multiple staff members and unassisted lifting of the patient by personnel. If correct position of the patient is not achieved at the outset of the operation, then the ensuing operation may become difficult or impossible. This has led to the time consuming and highly experienced based process of creating an individualized positioning solution for each patient using relatively nonspecicfic surgical tables, Coban self-adherent tape, surgical tape, pillows, and bolsters to address the variables of bady habitus, exposure, and safety needs. This lack of reproducibility may result in loss of position during the case, neuropraxias from pressure points, post-operative radiculitis or neck pain, or poorly performed surgeries due to inadequate exposure. In addition, high level providers may be required to work in series, creating room delays and inefficiency.
Concerns over complications related to positioning are not unfounded. Head and neck control in the anesthetized patient is critical. There have been reports of cranial nerve neuropraxias from aggressive head fixation in an attempt to control the patient body position and airway. The Occipital nerve can be damaged from pressure, and the lingual nerve can be damaged by wrapping straps under the chin with a laryngeal mask airway or endotracheal tube in place. Breathing is often compromised due to diaphragm hemiparalysis secondary to the interscalene block, as well as an obese abdomen causing superior pressure on the diaphragm and increased intraabdominal pressure. Physiological responses to the sitting position coupled with anesthetics may cause transient hypotension and bradycardia with resultant stroke, cardiac arrest, vision loss, or spinal cord ischemia. Carotid artery perfusion may be affected by hyperflexion or poor alignment of the cervical spine. At least one air embolism has resulted during shoulder arthroscopy in the beach chair position.
Some attempts have recently been made to provide a more reproducible, efficient, and safe way of making difficult positioning more easily achieved. Various prior shoulder positioners have used the concept of semi adjustable head fixation to a static table, and removable table pieces to allow exposure. While these can be effective, they also require a learning curve for personnel, and may contribute to critical malpositioning through aggressive head fixation, varying control of the center of mass, non power assisted lifting of large patients, and difficulty compensating for large variations in body habitus such as height and kyphosis. There can also be problems controlling the airway, which is usually covered by various drapes or bandages controlling the head.
The newest iteration of technology, offered by Quantum Ops, Inc (Ft. Wayne, Indiana) has several unique advantages which have increased ease and reproducibility of positioning. This concept uses lateral pads to control the body’s center of mass, then allows an adjustable head cradle to self adjust as the patient is brought into sitting position under power. Once a neutral spinal alignment is achieved, the head position can then be locked, allowing the head to be secured. An innovative Halo concept allows the ET tube to be completely free and easily accessed by anesthesia (as opposed to the concept of obscuring the ET tube with surgical tape, coban, or straps) The head cradle allows multiplane adjustments for certain clinical situations and body types: An AP adjustment bar allows the chair to adapt to extreme kyphosis or lordosis The quantum shoulder positioner allows for superior to inferior adjustments to range from 4’3’’ to 7’0’’ patient height, making it the only chair on the market useful in the pediatric population Coronal plane adjustment capability allows the surgeon to rotate the head away from the operative shoulder for surgical exposure. The radiolucent exposure around the shoulder joint is enhanced by a low profile lumbar support. The positioner is rated for up to 500 pounds for today’s increasingly common obese patient. It also features an easy loading mechanism on and off the table , as well as a power assisted lift of the patient using the OR table to protect staff members. The company is also producing an easily adjustable mechanical arm positioner to further enhance the reproducibility of the case.
By self adjusting to the patient in a rapid and reproducible manner, the Quantum Shoulder positioner may allay ancillary staff anxiety about positioning and allow more effective team participation during the time consuming positioning of the shoulder patient. In this way, the hidden cost of delayed OR turnover and poor positioning may be averted. Moreover, reproducible and rapid positioning may be achieved without sacrificing surgical access, time, or safety.