AOA Critical Issues Symposium: Mind the Gap: Addressing Confidence, Imposter Syndrome, and Perfectionism in Surgical Training.

ABSTRACT: Orthopaedic surgeons in training and in their careers can experience a lack of confidence and imposter syndrome. Confidence is built early through continuous improvement, accomplishments, support, and reinforcement. Although it is normal to lack confidence at times, the goal is to recognize this issue, work on visualizing success, and know when to seek help. Mentors can help mentees to build confidence and to normalize thoughts of insecurity and imposter syndrome. It is critical to develop and to maintain resilience, grit, emotional intelligence, courage, and vulnerability during training and throughout one's entire orthopaedic career. Leaders in the field must be aware of these phenomena, be able to talk about such issues, have methods to combat the harmful effects of imposter syndrome, and create a safe, supportive environment conducive to learning and working. Leading well builds not only confidence in oneself but also self-confidence in others. Leaders who are able to build the confidence of individuals will enhance team dynamics, wellness, and overall productivity as well as individual and organizational success.

Does Resection of the Posterior Longitudinal Ligament Affect the Stability of Cervical Disc Arthroplasty?

BACKGROUND: The need for posterior longitudinal ligament (PLL) resection during cervical total disc arthroplasty (TDA) has been debated. The purpose of this laboratory study was to investigate the effect of PLL resection on cervical kinematics after TDA. METHODS: Eight cadaveric cervical spine specimens were tested in flexion-extension (FE), lateral bending (LB), and axial rotation (AR) to moments of ±1.5 Nm. After testing the intact condition, anterior C5-C6 cervical discectomy was performed followed by PLL resection and implantation of a compressible, 6-degrees-of-freedom disc prosthesis (M6-C, Spinal Kinetics Inc, Sunnyvale, California). Next, a second prosthesis was implanted at C6-C7 with PLL intact. Finally, the C6-C7 PLL was resected while the disc prosthesis remained in place. Segmental range of motion (ROM) and stiffness in the high flexibility zone around the neutral posture were analyzed using repeated measures ANOVA. RESULTS: At C5-C6, following TDA and PLL resection, FE, LB, and AR ROMs decreased significantly. Anterior and posterior disc height, segmental lordosis, and flexion stiffness increased significantly. At C6-C7, TDA with the PLL intact resulted in a significant increase in anterior disc height and segmental lordosis with no change in posterior disc height. FE, LB, and AR ROMs all decreased significantly, while flexion stiffness increased significantly compared to intact. PLL resection at C6-C7 did not result in a notable change compared to TDA with PLL intact. At the same level, flexion stiffness decreased following PLL resection compared to TDA with a value closer to intact. Two-level TDA (C5-C7) with PLL resection did not result in a loss of segmental stability. CONCLUSION: PLL resection did not significantly affect motion segment kinematics following cervical TDA using a prosthesis with inherent stiffness. Motion segment stiffness loss after PLL resection can be compensated for by a TDA design that can provide resistance to angular motion.

Biomechanical Stability Analysis of a Stand-alone Cage, Static and Rotational-dynamic Plate in a Two-level Cervical Fusion Construct.

OBJECTIVE: To test the following hypotheses: (i) anterior cervical discetomy and fusion (ACDF) using stand-alone interbody spacers will significantly reduce the range of motion from intact spine; and (ii) the use of a static or a rotational-dynamic plate will significantly augment the stability of stand-alone interbody spacers, with similar beneficial effect when compared to each other. METHODS: Eleven human cadaveric subaxial cervical spines (age: 48.2 ± 5.4 years) were tested under the following sequence: (i) intact spine; (ii) ACDF at C4 -C5 using a stand-alone interbody spacer; (iii) ACDF at C5 -C6 and insertion of an interbody spacer (two-level construct); and (iv) randomized placement of either a two-level locking static plate or a rotational-dynamic plate. RESULTS: Insertion of stand-alone cage at C4 -C5 and C5 -C6 caused a significant decrease in the range of motion compared to intact spine (P < 0.05). Placement of both the locking and the rotational dynamic plate further reduced the range of motion at C4 -C5 and C5 -C6 compared to stand-alone cage (P < 0.01). No significant differences in range of motion restriction at either C4 -C5 or C5 -C6 were found when the two plating systems were compared (P > 0.05). CONCLUSIONS: Cervical stand-alone interbody spacers caused significant restriction in the range of motion. Both plates significantly augmented the stability of stand-alone interbody spacers, with similar stabilizing effect.

Compressive preload reduces segmental flexion instability after progressive destabilization of the lumbar spine.

STUDY DESIGN: Biomechanical human cadaveric study. OBJECTIVE: We hypothesized that increasing compressive preload will reduce the segmental instability after nucleotomy, posterior ligament resection, and decompressive surgery. SUMMARY OF BACKGROUND DATA: The human spine experiences significant compressive preloads in vivo due to spinal musculature and gravity. Although the effect of destabilization procedures on spinal motion has been studied, the effect of compressive preload on the motion response of destabilized, multisegment lumbar spines has not been reported. METHODS: Eight human cadaveric spines (L1-sacrum, 51.4 ± 14.1 yr) were tested intact, after L4-L5 nucleotomy, after interspinous and supraspinous ligaments transection, and after midline decompression (bilateral laminotomy, partial medial facetectomy, and foraminotomy). Specimens were loaded in flexion (8 Nm) and extension (6 Nm) under 0-N, 200-N, and 400-N compressive follower preload. L4-L5 range of motion (ROM) and flexion stiffness in the high-flexibility zone were analyzed using repeated-measures analysis of variance and multiple comparisons with the Bonferroni correction. RESULTS: With a fixed set of loading conditions, a progressive increase in segmental ROM along with expansion of the high-flexibility zone (decrease of flexion stiffness) was noted with serial destabilizations. Application of increasing compressive preload did not substantially change segmental ROM, but did significantly increase the segmental stiffness in the high-flexibility zone. In the most destabilized condition, 400-N preload did not return the segmental stiffness to intact levels. CONCLUSION: Anatomical alterations representing degenerative and iatrogenic instabilities are associated with significant increases in segmental ROM and decreased segmental stiffness. Although application of compressive preload, mimicking the effect of increased axial muscular activity, significantly increased the segmental stiffness, it was not restored to intact levels; thereby suggesting that core strengthening alone may not compensate for the loss of structural stability associated with midline surgical decompression. This suggests that there may be a role for surgical implants or interventions that specifically increase flexion stiffness and limit flexion ROM to counteract the iatrogenic instability resulting from surgical decompression. LEVEL OF EVIDENCE: N/A.

Cauda equina syndrome in an eleven-month-old infant following sacrococcygeal teratoma tumor resection and coccyx excision: case report.

STUDY DESIGN: A case report of cauda equina syndrome (CES) in an 11-month-old infant, following sacrococcygeal teratoma tumor resection and coccyx excision leading to a spinal epidural hematoma (SEH). OBJECTIVE: To illustrate a rare case of CES and SEH in an infant, and discuss the need for sealing access to the spinal canal after sacrococcygeal surgical resection and reconstruction. SUMMARY OF BACKGROUND DATA: To the authors' knowledge, this is the youngest patient reported to develop a SEH and CES, and the only patient reported in the literature to develop a SEH after coccyx excision. METHODS: Seventeen days after undergoing sacrococcygeal tumor resection and coccyx excision, the patient presented to the emergency room with a large distended bladder, loss of rectal tone, and significant weakness in the lower extremities. Magnetic resonance imaging of the thoracic and lumbar spine showed a large lesion in the dorsal epidural space extending from T12 to the tip of the communicating with the prior operative site by means of the previous coccyx resection. The infant was emergently brought to the operating room for decompression. RESULTS: The patient was discharged 6 days later with diminished neurologic function, but demonstrated significant improvement over the next 18 months and currently remains disease free and neurologically normal at age 7. CONCLUSION: This case demonstrates the need for future examination of sacrococcygeal surgical resection and subsequent reconstruction of excised structures to decrease the risk of communication with the epidural space.

Failure within one year following subtotal lumbar discectomy.

BACKGROUND: Reherniation within the first year following subtotal lumbar discectomy is a rare but noteworthy event. We performed a retrospective, case-controlled study to evaluate the clinical outcomes after early recurrent lumbar disc reherniation. METHODS: The records of 1320 patients who had undergone primary subtotal lumbar discectomy were analyzed retrospectively by an independent reviewer. Patients with documented reherniation within twelve months were evaluated with regard to the location of the reherniation, the neurologic status, the rate of reoperation, and the subjective outcome. Patients were evaluated on the basis of a physical examination and a review of medical records. Disc morphology, anular competence, and the presence of free fragments were categorized with use of a modified five-part Carragee classification system. The mean duration of follow-up for this group was 52.6 months. Clinical outcomes were assessed with use of the Oswestry score and the modified criteria of McNab. Twenty-nine historical control patients who had undergone uncomplicated subtotal lumbar discectomy were selected. RESULTS: We identified fourteen recurrent lumbar disc herniations within one year after the index procedure. All fourteen patients had radicular pain and weakness prior to, and complete relief of radiculopathy after, the index procedure. All reherniations occurred at the same level as the index procedure, but eight occurred in a different direction than the original herniation. All patients underwent reexploration and discectomy, and two underwent single-level posterolateral arthrodesis. Two patients underwent a third procedure. The average Oswestry score at the time of the latest follow-up was 6.4 for the recurrent herniation group, compared with 6.9 for the controls. The outcomes according to the modified McNab criteria were not significantly different between the groups, with the numbers available. The mean duration of follow-up after the second discectomy was 52.6 months. CONCLUSIONS: The rate of early reherniation after subtotal lumbar discectomy is low (1%). It is important to consider the possibility of iatrogenic instability during surgery on the lumbar spine for the treatment of reherniation. Patients who undergo reoperation because of early recurrent lumbar disc herniation can have clinical outcomes comparable with those of patients undergoing an uncomplicated subtotal lumbar discectomy.

Compressive preload improves the stability of anterior lumbar interbody fusion cage constructs.

BACKGROUND: Insertion of an anterior lumbar interbody fusion cage has been shown to reduce motion in a human spine segment in all loading directions except extension. The "stand-alone" cages depend on compressive preload produced by anular pretensioning and muscle forces for initial stabilization. However, the effect that the in vivo compressive preload generated during activities of daily living has on the construct is not fully understood. This study tested the hypothesis that the ability of the cages to reduce the segmental motions in flexion and extension is significantly affected by the magnitude of the externally applied compressive preload. METHODS: Fourteen specimens from human lumbar spines were tested intact and after insertion of two threaded cylindrical cages at level L5-Sl. They were subjected to flexion and extension moments under progressively increasing magnitudes of externally applied compressive follower preload from 0 to 1200 N. The range of motion at level L5-S1 after cage insertion was compared with the value achieved in the intact specimens at each compressive preload magnitude. RESULTS: The cages significantly reduced the L5-S1 flexion motion at all preloads (p < 0.05). They decreased flexion motion by 29% to 43% of that of the intact specimens for low preloads (0 to 400 N) and by 69% to 79% of that of the intact specimens under preloads of 800 to 1200 N. In extension, in the absence of an externally applied preload, the cages permitted 24% more motion than the intact segment (p < 0.05). In contrast, they reduced the extension motion at preloads from 200 to 1200 N. Under preloads of 800 to 1200 N, the reduction in extension motion after cage placement was 42% to 48% of that of the intact segment (p < 0.05). The reduction of motion in both flexion and extension after cage placement was significantly greater at preloads of 800 to 1200 N compared with the motion reductions at preloads of < or =400 N (p < 0.05). CONCLUSIONS: In contrast to the observed extension instability under anular tension preload only, the two-cage construct exerted a stabilizing effect on the motion segment (a reduction in segmental motion) in flexion as well as extension under externally applied compressive preloads of physiologic magnitudes. The external compressive preload significantly affected the stabilization provided by the cages. The cages provided substantially more stabilization, both in flexion and in extension, at larger preloads than at smaller preloads. CLINICAL RELEVANCE: The study suggests that the segment treated with an anterior lumbar interbody fusion cage is relatively less stable under conditions of low external compressive preload. The magnitude of preload required to achieve stabilization with stand-alone cages may be only partially achieved by anular pretensioning. Since the magnitude of the preload across the disc space due to muscle activity can vary with activities of daily living, supplemental stabilization of the cage construct may provide a more predictably stable environment for lumbar spine fusion.