Page 25 - ISAKOS 2019 Newsletter Vol II

02 Lateral view of postless setup 03 for right hip arthroscopy. The
blue asterisk indicates the
anterior superior iliac spine.
In routine hip arthroscopy, the hip is in approximately 0° to 5° flexion, 0° of adduction, and 10° of internal rotation (depending on estimated,
or known, femoral version).
Upon application of distraction, the degree
of anterior pelvic tilt (and concurrent lumbar lordosis) must be recognized and corrected if needed.
The application of traction during procedures involving a postless system (with minor variable degrees of Trendelenburg positioning) has demonstrated safety, without a reduction in venous blood flow (as demonstrated with Doppler ultrasound) or altered nerve function (as indicated by somatosensory evoked potentials and transcranial motor evoked potentials) in the distracted limb4. Furthermore, arthroscopy with use of a postless technique has shown that muscle tissue damage (as demonstrated by the levels of creatine phosphokinase [CPK] and D-dimer) is subclinical, transient, and significantly less than that when a post is used. There is currently limited clinical evidence on postoperative outcomes following hip arthroscopy without a perineal post. The seminal publication on outcomes following postless hip arthroscopy demonstrated a 0% rate of groin-related soft-tissue or nerve complications after 1,000 consecutive hip arthroscopy procedures5. In addition, there were no complications (e.g., friction burns, blisters, bruises, contusions) secondary to the friction necessary to achieve distraction. However, in that study, the surgeon utilized Trendelenburg positioning (mean and standard deviation, 11° ± 2°).
Advantages
Disadvantages
CURRENT CONCEPTS
Upon initiation of traction with either method (using gross or fine distraction), the surgeon must be cognizant of the degree of friction between the lower back and buttocks and the table. With greater force of distraction pull, this friction can lever the pelvis into more anterior tilt (Fig. 3). If this increased tilt is recognized, the buttocks can be gently lifted off the bed and the tilt corrected after distraction is achieved. Otherwise, portal placement may be slightly more proximal than normal. Both methods of distraction permit surgeons to perform surgery without making any changes in their actual surgical techniques, eliminating the learning curve associated with the implementation of the postless system.
Overview
Performing hip arthroscopy without a perineal post has several advantages and few disadvantages. Although early evidence is limited to a few retrospective investigations and technique papers, the outcomes have been excellent. First and foremost, the use of a postless system has demonstrated safety. Additionally, there appears to be a minimal learning curve, with no substantial changes in terms of routine hip arthroscopy techniques. Trendelenburg positioning is not required. Perineal post-related complications are eliminated and pain is significantly reduced in association with postless arthroscopic hip-preservation surgery.
Table II Advantages and Disadvantages of Postless Hip Arthroscopy
• No compression on perineum, eliminating soft- tissue and nerve injury due to post
• No compression on perineum, with reduced postoperative pain and medication requirements
• Permits advanced procedures that may require extended traction times
• Permits enhanced trainee education, with less concern about traction- related complications while teaching trainees or surgeons
• Can be performed with or without Trendelenburg positioning
• No limit on patient height (a perineal post limits taller patients due to post-foot/ boot length)
• Heavier patients typically easier distraction (including older, stiff males in whom it is usually challenging to obtain sufficient traction)
• Greater available range of motion for dynamic examination
• Minimal learning curve required
• Setup may require additional operating room staff training
• Cost may increase
with purchase of new equipment (pad for table surface, new table)
• Achievement of distraction in lighter patients may
be more difficult than expected (less force on table due to gravity, less friction)
• Lack of a post may decrease patient stability on the table, requiring vigilance with dynamic examination and hip motion
• Friction between skin and table may induce greater anterior pelvic tilt with traction
ISAKOS NEWSLETTER 2019: VOLUME II 23