Motor Evoked Potential Recordings from the Urethral Sphincter Muscles (USMEPs) during Spine Surgeries.

Bowel and bladder function are at risk during tumor resection of the conus, cauda equina, and nerve roots. This study demonstrates the ability to acquire transcranial electrical motor evoked potentials (TCeMEPs) from the urethral sphincter muscles (USMEPs) by utilizing a urethral catheter with an embedded electrode. A retrospective analysis of intraoperative neurophysiological monitoring (IONM) data from nine intradural tumors, four tethered cord releases, and two spinal stenosis procedures was performed (n = 15).

Contemporaneous Evaluation of Intraoperative Ulnar and Median Nerve Somatosensory Evoked Potentials for Patient Positioning: A Review of Four Cases.

Somatosensory evoked potentials (SSEPs) are a valuable tool for assessing changes in peripheral nerve pathways caused by patient positioning during spinal surgeries. These changes, when left undiagnosed, may lead to postoperative neurological sequelae. Why an upper extremity SSEP attenuates due to positioning is not necessarily clear and can be multifactorial, affecting the peripheral nerves or elements of the brachial plexus.

Causal factors for position-related SSEP changes in spinal surgery.

Background Context: Somatosensory evoked potentials (SSEPs) are effective in detecting upper extremity positional injuries; however, causal factors for which patient population is most at risk are not well established.

Purpose: To review causal factors for intraoperative SSEP changes due to patient positioning.

Study Design: A case series with retrospective chart analysis was performed.

Motor evoked potentials for femoral nerve protection in transpsoas lateral access surgery of the spine.

Detecting potential intraoperative injuries to the femoral nerve should be the main goal of neuromonitoring of lateral lumber interbody fusion (LLIF) procedures. We propose a theory and technique to utilize motor evoked potentials (MEPs) to protect the femoral nerve (a peripheral nerve), which is at risk in LLIF procedures. MEPs have been advocated and widely used for monitoring spinal cord function during surgical correction of spinal deformity and surgery of the cervical and thoracic spine, but have had limited acceptance for use in lumbar procedures.

Saphenous nerve somatosensory evoked potentials: a novel technique to monitor the femoral nerve during transpsoas lumbar lateral interbody fusion.

Study Design: A retrospective analysis of a case series was performed.

Objective: To describe a novel technique to monitor femoral nerve function by analyzing the saphenous nerve somatosensory evoked potential (SSEP) during transpsoas surgical exposures of the lumbar spine.

Summary Of Background Data: During transpsoas direct lateral approaches to the lumbar spine, electromyography monitoring is frequently advocated; however, sensory and motor neurological complications are still being reported.

Factors associated with prolonged wound drainage after primary total hip and knee arthroplasty.

Background: Prolonged wound drainage following total hip or total knee arthroplasty has been associated with an increased risk of postoperative morbidity. The purpose of this study was to determine the pharmacologic, surgical, and patient-specific factors that are associated with prolonged wound drainage and the relationship of this complication to the length of hospital stay and the rate of wound infections.

Methods: We conducted a retrospective observational study of 1211 primary total hip arthroplasties and 1226 primary total knee arthroplasties.

A proposed classification of supracondylar femur fractures above total knee arthroplasties.

A new classification system is proposed for supracondylar femur fractures above total knee arthroplasties based on fracture location relative to the femoral component. Radiographs of 28 cases were evaluated and classified according to the proposed system by 12 physicians: 3 trauma specialists, 3 adult reconstruction specialists, 3 musculoskeletal radiologists, and 3 orthopaedic residents. The same 12 physicians reevaluated the same 28 cases 3 months later.

The effect of end screw orientation on the stability of anterior instrumentation in cyclic lateral bending.

Background Context: Screw pullout at the proximal or distal end of multilevel anterior instrumentation can occur clinically. Previous laboratory studies have shown that angulation of vertebral body screws increases screw pullout strength and stability in toggling.

Purpose: To determine the effect of end screw angulation on instrumentation construct stability after cyclic, lateral bending.

Efficacy of abduction bracing in the management of total hip arthroplasty dislocation.

A retrospective review of total hip arthroplasty (THA) dislocations was performed to determine the effectiveness of abduction bracing following closed reduction. Patients were grouped as a first-time dislocation (n = 91) or recurrent dislocation (n = 58) and whether or not they received an abduction brace; re-dislocation defined failure of treatment. The mean follow-up was 4.

Periprosthetic femoral fractures above total knee replacements.

Periprosthetic femoral fractures above total knee replacements can be managed by a variety of methods, including casting, open reduction and internal fixation, external fixation, or revision arthroplasty. Because no single method has emerged as the optimal choice for all such fractures, it is important to understand which options are appropriate for each fracture pattern. Early classification systems focused on displacement as a major indication for either surgical or nonsurgical management.

The effect of an attachable lateral support plate on the stability of intertrochanteric fracture fixation with a sliding hip screw.

Background: Use of a sliding hip screw (SHS) alone for some unstable intertrochanteric femur fractures can allow excessive medial shaft displacement during impaction. This study evaluated the effect of an attachable lateral support plate on these fractures after loading.

Methods: Unstable, three-part intertrochanteric fractures were created in 10 matched pairs of embalmed femurs that were instrumented with 135-degree SHSs with or without an attachable lateral support plate.

Instability following total hip arthroplasty.

Dislocation is the second most common complication of total hip arthroplasty. Most dislocations occur early in the postoperative period and are caused by patient factors, surgical factors, or a combination of both. Patient factors that predispose to postoperative dislocation include previous surgery and neurologic impairment.

Use of structural bone graft with cementless acetabular cups in total hip arthroplasty.

We retrospectively studied 15 primary and 13 revision total hip arthroplasties in which structural acetabular bone grafts were used in conjunction with cementless acetabular cups (for 11 type I segmental acetabular defects and 17 type III combined segmental/cavitary acetabular defects). Mean follow-up was 7.7 years in the primary and 6.

Thermal energy in arthroscopic surgery of the wrist.

Thermal energy in arthroscopic surgery needs further follow-up evaluation to clarify the potential benefits, specifically with respect to thermal shrinkage. Although the initial findings are promising, the long-term results need to be compared with other accepted standards of management. Preliminary findings seem to show that the addition of these surgical instruments and expanding operative techniques have definite roles in arthroscopic wrist surgery, as demonstrated through meticulous synovectomies and precise tissue debridement, along with the possible thermal shrinkage potential.

Effect of piriformis versus trochanteric starting point on fixation stability of short intramedullary reconstruction nails.

Recently, a new, shorter IM nail using two 6 mm reconstruction screws for proximal fixation was introduced in two versions for femoral insertion: piriformis fossa (FAN) and greater trochanter (TAN). These nails were compared experimentally for their fixation stability, proximal load transmission, and failure strength in an unstable intertrochanteric fracture model in cadaveric femurs. Vertical and axial loads were first applied to the intact femurs.

Orthopaedic manifestations of systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease of unknown origin. It affects multiple organ systems, but most frequently the musculoskeletal system. Highly variable manifestations include small and large joint involvement, spinal involvement, periarticular tissue symptoms, and complications associated with chronic steroid use such as osteonecrosis, osteoporosis, and stress fractures.

Myofibroblasts differentiate from fibroblasts when plated at low density.

Myofibroblasts, defined by their expression of smooth muscle alpha-actin, appear at corneal and dermal incisions and promote wound contraction. We report here that cultured fibroblasts differentiate into myofibroblasts by a cell density-dependent mechanism. Fibroblasts seeded at low density (5 cells per mm2) produced a cell culture population consisting of 70-80% myofibroblasts, 5-7 days after seeding.