A Characterization of Sensory and Motor Neural Dysfunction in Patients Undergoing Hip Arthroscopic Surgery: Traction- and Portal Placement–Related Nerve Injuries

Abstract

Background:There is a paucity of prospectively collected data as they relate to nerve injuries after hip arthroscopic surgery. Studies describing the relationship of neurological injuries to portal placement and the duration and magnitude of traction force with regular and standardized patient follow-up protocols are limited.Purpose/Hypothesis:The purpose of this study was to characterize nerve deficits in a series of patients undergoing hip arthroscopic surgery as these deficits relate to axial traction and portal placement. It was hypothesized that in patients who presented without nerve deficits after surgery, the magnitudes of traction-related measurements would exceed previous recommendations based on expert opinion (<50 lb). Additionally, it was hypothesized that sensory disturbance would commonly be observed (≥16%) localized to the distal anterolateral thigh related to portal placement.Study Design:Case series; Level of evidence, 4.Methods:A total of 45 patients scheduled to undergo hip arthroscopic surgery between July 2012 and February 2014 were included in this study. Traction force was measured and recorded every 5 minutes during surgery, and patients were assessed by a physical examination for deficits in light touch sensitivity at all lower extremity dermatomes preoperatively and at 3 weeks, 6 weeks, 3 months, and 1 year postoperatively. Patients were also tested for strength deficits and rated on the manual muscle testing grading scale. Patients reported modified Harris Hip Score (mHHS), Hip Outcome Score–Activities of Daily Living and –Sport subscales (HOS-ADL and HOS-Sport, respectively), Short Form–12 (SF-12) mental and physical component summaries, and international Hip Outcome Tool–12 (iHOT-12) scores preoperatively and at 1 year postoperatively.Results:Thresholds for maximum traction force, mean traction force, duration of traction, and traction impulse were 120 lb, 82 lb, 61 minutes, and 7109 lb·min, respectively, below which no patients presented with sensory or motor dysfunction thought to be related to traction. A minority (17.8%) of patients presented with highly localized, distal anterolateral sensory deficits suggestive of injuries related to portal placement, and 2.2% of patients presented with perineal numbness localized to the distribution of the pudendal nerve. All nerve deficits had resolved by 1-year follow-up.Conclusion:This study suggests that it may be possible to apply more axial traction force for a longer duration than expert opinion has previously suggested, without significant and, in the majority of cases (82.2%), any traction-related short-term complications. Transient traction- and portal placement–related nerve injuries after hip arthroscopic surgery may be more frequent (31.1% in this study) than have been reported historically.

The traction force of the pulled limb in hip arthroscopic surgery is determined by stiffness coefficient which is significantly related to muscle volume

“…The trend of traction force in hip arthroscopic surgery at different physical states reflects the tension of surrounding tissues and muscles. Anatomically, the hip joint capsule is composed of three main fibrous ligaments, including the iliac ligament, sciatic ligament and pubic ligament [3, 14]. Therefore, different surgical approaches may affect the resistance to traction by the joint capsule.…”

“…Due to trauma and extrusion, some complications may occur, such as iatrogenic chondral or/and labral injury, heterotopic ossification and temporary or permanent nerve injury [9]. These injuries are related to traction force [1, 3, 17]. Therefore, postoperative complications are hoped to be reduced by evaluating traction force before and during surgery.…”

Use of a larger surface area tip on bipolar radiofrequency wands in hip arthroscopy is associated with significantly lower traction and total surgery times

“…Prior studies have tried to mitigate the effects of traction via patient positioning as opposed to measures that reduce surgical or traction time. For example, traction time, traction force, perineal post modifications, postless techniques, fluid inflow rate and fluid pressure have all been studied in attempts to decrease hip arthroscopy complications [ 7–11 ]. One prior study evaluated two different types of radiofrequency ablation wands (plasma ablation versus standard ablation) during rotator cuff repair surgery and reported no difference in diathermy efficiency [ 19 ].…”

“…These injuries may present as pudendal nerve injury, genitourinary and gynecologic soft tissue damage [ 5 , 6 ]. These complications can be devastating and have been correlated with multiple factors among which include the magnitude of distracting force and duration of traction [ 7–9 ]. Thus, any innovation that can improve the surgical technique by reducing complication risk is welcomed.…”

Postless Hip Arthroscopy: A Technical Note on Obtaining Distraction

“…Limiting traction time and magnitude of traction during surgery also have been shown to decrease the incidence of these traction-related injuries. 5 In this Technical Note, we present our preferred technique for postless hip distraction.…”