A Proposal for a Standardized Nomenclature of the C-arm Movements.

No formal didactic source exists concerning terminology for movement of the C-arm in the operating room (OR). Many terminologies exist, breeding confusion among OR staff. The objective of this study was to survey the existing C-arm movement terminologies among orthopaedic surgeons and radiologic technologists and propose a standardized nomenclature moving forward. Methods: Forty-six orthopaedic surgeons and 70 radiologic technologists were surveyed. Pertinent product manuals and literature from PubMed were reviewed to find existing terms for the C-arm movement. A focus group of orthopaedic surgeons and radiologic technologists was formed and a standardized nomenclature of the C-arm terminology was developed using the Delphi method. Results: The survey response rate was 71%. The mean percentage of agreement on terms to describe movement was 47% (range, 13% to 83%). Agreement on terms to describe direction was 46% (range, 23% to 73%), and multiple frames of reference were described. No consensus was found by searching the product manuals. Using the Delphi method, we arrived at a standardized nomenclature for the C-arm movement that is reproducible and familiar. Discussion: A standardized terminology for the C-arm movement is described that will help fill a void in OR communication, combat confusion, and provide reproducible results during orthopaedic cases.

Distal fibular malrotation and lateral ankle contact characteristics.

BACKGROUND: Any amount of malreduction of the syndesmotic joint compared with the uninjured syndesmosis has been associated with an adverse effect on functional outcome. The amount of malrotation that may lead to clinically relevant pressure change in this joint has not been reported. Our purpose was to determine whether small degrees of external and internal malrotation would be associated with statistically significant changes in contact pressure in the tibiofibular and talofibular articulations. METHODS: Twelve cadaveric ankles were osteotomized above the syndesmosis and instrumented with a rotatable distal fibula plate. Sensors at the distal tibiofibular and talofibular articulations recorded contact pressure and area at neutral position and at 5 and 10° of external and internal malrotation through a full range of ankle motion. RESULTS: Compared with neutral rotation, there was a significant decrease in contact pressure at the talofibular articulation with external rotation of 5° (103±113kPa versus 52±69kPa; P=0.01) and 10° (43±62kPa; P=0.01) in plantarflexion.Contact pressure at the tibiofibular articulation in plantarflexion increased with 10° of internal malrotation compared with neutral rotation (56±30kPa versus 74±38kPa; P=0.05) in plantarflexion. Contact area decreased significantly with plantarflexion and 10° of external rotation and increased significantly in plantarflexion and after cyclic loading with 10° of internal rotation (P≤0.05). CONCLUSION: Any degree of distal fibular external rotation significantly reduced contact pressure in the talofibular articulation with plantarflexion. A minimal increase in contact pressure was found in the tibiofibular and talofibular joints with plantarflexion and mild internal rotation of 5°, but pressure increased significantly in both articulations with 10° of internal rotation. The findings support clinical findings that subtle degrees of fibular malrotation may be associated with alteration of lateral ankle mechanics. LEVEL OF EVIDENCE: Controlled biomechanical study.

Distal triceps transosseous cruciate versus suture anchor repair using equal constructs: a biomechanical comparison.

BACKGROUND/HYPOTHESIS: Suture anchor-based repair has been advocated for repair of distal triceps avulsion, but previous models have used an unequal number of sutures across the repair site. We hypothesized that there would be no difference in triceps tendon displacement between gold standard repair with transosseous cruciate bone tunnels and suture anchor repair with an equal number of sutures in the constructs. METHODS: The triceps tendon footprint was measured in 20 cadaveric elbows (10 matched pairs), and a distal triceps tendon rupture was created. The specimens in each pair were randomly assigned to transosseous cruciate repair or knotless, double-row, anatomic footprint, suture anchor repair. Specimens underwent cyclic loading to 1500 cycles and then load to failure. Footprint uncoverage was measured at 1500 cycles. Data for medial and lateral triceps tendon displacement, footprint uncoverage, and failure load were obtained. RESULTS: Triceps displacement did not differ significantly between the transosseous cruciate and the suture anchor repair group at 1500 cycles on the medial (3.6 ± 0.9 mm vs. 4.3 ± 1.6 mm [mean ± standard deviation], respectively; P = .27) and lateral side (3.1 ± 1.2 mm vs. 2.0 ± 1.2 mm, respectively; P = .06). No other differences were found between the constructs. DISCUSSION/CONCLUSION: Transosseous cruciate distal triceps repair and knotless double-row suture anchor repair using constructs with an equal number of sutures showed no significant difference in tendon displacement at 1500 loading cycles. These findings suggest that the biomechanical strength of an all-suture construct is not different from that of suture anchors for repair of distal triceps avulsions.

Treatment of a Pediatric T-type Intercondylar Humerus Fracture With Hybrid Percutaneous Pinning and External Fixation.

T-type intercondylar fractures of the distal humerus are rare injuries in skeletally immature patients. Few studies are available to guide the treatment of these injuries. Small case series and expert recommendations suggest superiority of the open approach for direct reduction of the articular surface. This approach poses risks of vascular compromise and elbow stiffness. However, success with percutaneous intercondylar screw fixation has been described for simple split patterns. The authors present a case that illustrates a novel percutaneous technique to treat this fracture type. A healthy 8-year-old boy sustained a T-type intercondylar fracture of the distal humerus (AO 13-C1). Excellent reduction was noted after closed reduction and crossed percutaneous pinning. Compression was applied across the pins through a small external fixator bar to address the intercondylar split component. At the 6-week postoperative clinic visit, the pins and fixator were removed uneventfully, and normal healing with full range of elbow motion was noted. This case report describes a simple, minimally invasive technique to treat uncomplicated T-type intercondylar fractures of the distal humerus in skeletally immature patients. Practitioners familiar with percutaneous fixation of supracondylar fractures can easily perform this technique. The described technique spares an open dissection and avoids permanent implants around the joint. Further multicenter research is warranted to determine the long-term outcomes and safety of the described technique. [Orthopedics. 2017; 40(6):e1096-e1098.].

Rare Complications of Cervical Spine Surgery: Horner's Syndrome.

STUDY DESIGN: A multicenter retrospective case series. OBJECTIVE: Horner's syndrome is a known complication of anterior cervical spinal surgery, but it is rarely encountered in clinical practice. To better understand the incidence, risks, and neurologic outcomes associated with Horner's syndrome, a multicenter study was performed to review a large collective experience with this rare complication. METHODS: We conducted a retrospective multicenter case series study involving 21 high-volume surgical centers from the AOSpine North America Clinical Research Network. Medical records for 17 625 patients who received subaxial cervical spine surgery from 2005 to 2011 were reviewed to identify occurrence of 21 predefined treatment complications. Descriptive statistics were provided for baseline patient characteristics. Paired t test was used to analyze changes in clinical outcomes at follow-up compared to preoperative status. RESULTS: In total, 8887 patients who underwent anterior cervical spine surgery at the participating institutions were screened. Postoperative Horner's syndrome was identified in 5 (0.06%) patients. All patients experienced the complication following anterior cervical discectomy and fusion. The sympathetic trunk appeared to be more vulnerable when operating on midcervical levels (C5, C6), and most patients experienced at least a partial recovery without further treatment. CONCLUSIONS: This collective experience suggests that Horner's syndrome is an exceedingly rare complication following anterior cervical spine surgery. Injury to the sympathetic trunk may be limited by maintaining a midline surgical trajectory when possible, and performing careful dissection and retraction of the longus colli muscle when lateral exposure is necessary, especially at caudal cervical levels.

Epidural Hematoma Following Cervical Spine Surgery.

STUDY DESIGN: A multicentered retrospective case series. OBJECTIVE: To determine the incidence and circumstances surrounding the development of a symptomatic postoperative epidural hematoma in the cervical spine. METHODS: Patients who underwent cervical spine surgery between January 1, 2005, and December 31, 2011, at 23 institutions were reviewed, and all patients who developed an epidural hematoma were identified. RESULTS: A total of 16 582 cervical spine surgeries were identified, and 15 patients developed a postoperative epidural hematoma, for a total incidence of 0.090%. Substantial variation between institutions was noted, with 11 sites reporting no epidural hematomas, and 1 site reporting an incidence of 0.76%. All patients initially presented with a neurologic deficit. Nine patients had complete resolution of the neurologic deficit after hematoma evacuation; however 2 of the 3 patients (66%) who had a delay in the diagnosis of the epidural hematoma had residual neurologic deficits compared to only 4 of the 12 patients (33%) who had no delay in the diagnosis or treatment (P = .53). Additionally, the patients who experienced a postoperative epidural hematoma did not experience any significant improvement in health-related quality-of-life metrics as a result of the index procedure at final follow-up evaluation. CONCLUSION: This is the largest series to date to analyze the incidence of an epidural hematoma following cervical spine surgery, and this study suggest that an epidural hematoma occurs in approximately 1 out of 1000 cervical spine surgeries. Prompt diagnosis and treatment may improve the chance of making a complete neurologic recovery, but patients who develop this complication do not show improvements in the health-related quality-of-life measurements.

C5 Palsy After Cervical Spine Surgery: A Multicenter Retrospective Review of 59 Cases.

STUDY DESIGN: A multicenter, retrospective review of C5 palsy after cervical spine surgery. OBJECTIVE: Postoperative C5 palsy is a known complication of cervical decompressive spinal surgery. The goal of this study was to review the incidence, patient characteristics, and outcome of C5 palsy in patients undergoing cervical spine surgery. METHODS: We conducted a multicenter, retrospective review of 13 946 patients across 21 centers who received cervical spine surgery (levels C2 to C7) between January 1, 2005, and December 31, 2011, inclusive. P values were calculated using 2-sample t test for continuous variables and χ2 tests or Fisher exact tests for categorical variables. RESULTS: Of the 13 946 cases reviewed, 59 patients experienced a postoperative C5 palsy. The incidence rate across the 21 sites ranged from 0% to 2.5%. At most recent follow-up, 32 patients reported complete resolution of symptoms (54.2%), 15 had symptoms resolve with residual effects (25.4%), 10 patients did not recover (17.0%), and 2 were lost to follow-up (3.4%). CONCLUSION: C5 palsy occurred in all surgical approaches and across a variety of diagnoses. The majority of patients had full recovery or recovery with residual effects. This study represents the largest series of North American patients reviewed to date.

Iatrogenic Spinal Cord Injury Resulting From Cervical Spine Surgery.

STUDY DESIGN: Retrospective cohort study of prospectively collected data. OBJECTIVE: To examine the incidence of iatrogenic spinal cord injury following elective cervical spine surgery. METHODS: A retrospective multicenter case series study involving 21 high-volume surgical centers from the AOSpine North America Clinical Research Network was conducted. Medical records for 17 625 patients who received cervical spine surgery (levels from C2 to C7) between January 1, 2005, and December 31, 2011, were reviewed to identify occurrence of iatrogenic spinal cord injury. RESULTS: In total, 3 cases of iatrogenic spinal cord injury following cervical spine surgery were identified. Institutional incidence rates ranged from 0.0% to 0.24%. Of the 3 patients with quadriplegia, one underwent anterior-only surgery with 2-level cervical corpectomy, one underwent anterior surgery with corpectomy in addition to posterior surgery, and one underwent posterior decompression and fusion surgery alone. One patient had complete neurologic recovery, one partially recovered, and one did not recover motor function. CONCLUSION: Iatrogenic spinal cord injury following cervical spine surgery is a rare and devastating adverse event. No standard protocol exists that can guarantee prevention of this complication, and there is a lack of consensus regarding evaluation and treatment when it does occur. Emergent imaging with magnetic resonance imaging or computed tomography myelography to evaluate for compressive etiology or malpositioned instrumentation and avoidance of hypotension should be performed in cases of intraoperative and postoperative spinal cord injury.

Total Knee Arthroplasty after Complete Patellectomy: A Review.

The absence or dysfunction of the knee extensor mechanism accelerates degenerative joint disease and complicates knee arthroplasty. Various treatment strategies have been suggested to improve outcomes in total knee arthroplasties after patellectomy (semi- or constrained components, autograft, allograft, prosthetic reconstruction), but the optimal management of this condition is not known. The purpose of this report is to review the relevant basic biology and biomechanics of the patella and the extensor mechanism, and to review the current literature on the management of complete patellectomy during total knee arthroplasty. Tissue engineered heart valves, BMMSCs, oscillatory shear stress, nicotine, F-actin filaments, cell differentiation, endothelial cells.

Influencing medical student education via a voluntary shadowing program for trauma and acute care surgery.

Decreasing application into trauma surgery may be attributed to decreased exposure during medical school. We instituted a voluntary trauma call program for students to provide exposure to the field. After 3 years, participants completed a survey to gauge their experience. Of 126 students who participated, 68 completed the survey (54%). Interest in trauma surgery among students not previously planning on a career in surgery (n = 48) improved after the experience (4.4-5.3 of 10 points; P < .005). Operative experience, exposure to a higher number of trauma cases, and time with residents were associated with increased interest in trauma surgery. Witnessing patient death for the first time was associated with decreased interest in trauma surgery. A voluntary overnight shadowing program improves medical students' perceptions of trauma surgery and increases their reported likelihood to apply into a surgical residency.

Reduced re-infection rates with postoperative oral antibiotics after two-stage revision hip arthroplasty.

BACKGROUND: Surgeons are often trying to decreased reinfection rates following two-stage reimplantation arthroplasty, which range from 3.2% to 13% because multiple staged revision procedures for infection can be costly and have high morbidity. We therefore asked: (1) Did the use of postoperative oral antibiotics reduce reinfection rates after 2-staged revision of THA? And (2) how did this compare with the infection rate after aseptic revision procedures? METHODS: We identified all patients who underwent two-stage revision THA for a periprosthetic deep hip infection and found 66 patients (67 hips) who had a minimum 24 months' followup. Twenty-two of the 66 procedures (33%) were followed by a minimum of 14 days of postoperative oral antibiotics (mean, 36 days; range, 14 days to lifelong), while 44 were prescribed only immediate parenteral postoperative antibiotic therapy (mean, 1.3 days; range, 1-3 days). We then identified 407 patients (410 hips) who underwent aseptic revision hip arthroplasty and evaluated the infection rate in these patients for comparison; these patients were treated with 24 hours of postoperative parenteral antibiotics. The authors used previously described creteria to establish the presence of infection. RESULTS: There were no reinfections in the group receiving oral postoperative antibiotics compared to six reinfections (13.6%) in the 44 patients not receiving oral antibiotics. We observed infection in 2 of the 410 hips (0.5%) revised for aseptic reasons. CONCLUSIONS: We believe that our findings warrant further investigation for using postoperative oral antibiotics after reimplantation for periprosthetic infection in an effort to decrease the likelihood and risks associated with additional revision arthroplasty procedures.

Reduced dislocation rates and excellent functional outcomes with large-diameter femoral heads.

The purpose of this study was to compare the dislocation rates, functional outcomes, and radiographic results between large- and small-diameter femoral head components. A total of 225 patients (248-hips) who received total hip arthroplasties with large-diameter components (36mm or greater) were compared to 501 patients (559-hips) who received smaller diameter components (less than 36mm). Rates of dislocation and revision, Harris hip score, radiographic findings, and complications were compared between the groups. At a mean follow-up of approximately 5years, a significantly higher rate of dislocation was noted in the small-diameter group (10 of 559) compared to the large-diameter group (0 of 248). The overall implant survivorship, mean Harris hip scores, complication rates, and radiographic outcomes were similar for the two groups. The authors believe that large-diameter components significantly reduced the risk of dislocation in susceptible patients, while preserving good to excellent functional outcomes.

Inheritable risk factors for venous thromboembolism in patients undergoing lower extremity total joint arthroplasty.

Venous thromboembolism is a common and undesirable complication of both total hip and knee arthroplasty. The basic biology and major modifiable risk factors predisposing to thromboembolism are well established, but a complete understanding of the role and management of inherited coagulopathies is lacking. In this manuscript, we have attempted to review the fundamental pathophysiology of the coagulation cascade, analyze recent literature on heritable coagulopathies leading to venous thromboembolism in patients undergoing lower extremity joint arthroplasty, and discuss how an understanding of such factors may affect clinical practice. We advocate that a sound understanding of inherited coagulopathies, as they relate to hip and knee arthroplasty, may help to aid decision making regarding prophylaxis which may eventually lead to an established algorithm system for screening and managing patients at high risk for adverse thromboembolic events.

Risk of dislocation using large- vs. small-diameter femoral heads in total hip arthroplasty.

BACKGROUND: Dislocation remains a difficult problem in total hip arthroplasty. Large-diameter femoral heads may lower the incidence of dislocation by enhancing the jump distance and decreasing impingement, but their performance against small-diameter heads has not been assessed. This study compared the mid-term radiographic and functional outcomes of two matched cohorts of patients undergoing total hip arthroplasty who had a high pre-operative risk for dislocation and who received either small-diameter (26- or 28-millimeters) or large-diameter (≥36-millimeters) femoral heads. METHODS: All patients who received large-diameter heads (≥36-millimeter) between 2002 and 2005, and who had pre-operative risk factors for dislocation, were identified in the institution's joint registry. Forty-one patients (52 hips) who received large-diameter heads were identified, and these patients were matched to 48 patients (52 hips) in the registry who received small-diameter femoral heads. RESULTS: At mean final follow-up of 62 months (range, 49 to 101 months), both groups achieved excellent functional outcomes as measured by Harris Hip scores, with slightly better final scores in the large-diameter group (90 vs. 83 points). No patient showed any radiographic signs of loosening. No patient dislocated in the large-diameter femoral head group; the smaller-diameter group had a greater rate of dislocation (3.8%, 2 out of 52). CONCLUSIONS: Large-diameter femoral head articulations may reduce dislocation rates in patients who have a high pre-operative risk for dislocation while providing the same functional improvements and safety as small-diameter bearings.

Discrepancies between frozen and paraffin tissue sections have little effect on outcome of staged total knee arthroplasty revision for infection.

BACKGROUND: Intraoperative analysis of frozen tissue samples has been used to diagnose periprosthetic joint infection in revision total knee arthroplasty, but the precision and reliability of this test throughout staged revision arthroplasty have not been well characterized. We undertook this study to determine the rate of discrepancy between frozen and permanent histopathologic samples in the diagnosis of periprosthetic infection at both the index total knee arthroplasty revision procedure and the attempted reimplantation. METHODS: Seventy-six patients who underwent staged revision of a total knee arthroplasty for apparent infection had samples for frozen and permanent sections obtained at both the index revision procedure and subsequent reimplantation attempts. We investigated the rate of discrepancy between these frozen and permanent sections. The clinical and radiographic outcomes of patients with and without concordance between the frozen and permanent sections were reviewed. RESULTS: Concordance was noted between 297 (97.7%) of the 304 frozen sections and the permanent sections. Seven discrepancies between diagnoses based on frozen and permanent sections were noted; however, additional samples in these patients were positive and management was not affected. Fewer discrepancies were found during the initial revision procedure (one of 92, 1%) compared with reimplantation (six of 212, 3%). The mean time to reimplantation was similar between patients with and without a discrepancy in diagnosis between the frozen and permanent sections (185 compared with 157 days). The rate of discrepancy between frozen and permanent histopathologic sections was low, and no discrepancy affected the final outcome of any patient. CONCLUSIONS: The rate of discrepancy between frozen and permanent histopathologic samples was low for both index revision and reimplantation procedures. In rare instances of discrepancy, management should be unaffected provided a sufficient number of samples were collected.

How do frozen and permanent histopathologic diagnoses compare for staged revision after periprosthetic hip infections?

Histopathologic analysis of frozen tissue samples is used to aid the intraoperative diagnosis of periprosthetic hip infections, but there are concerns about reliability. The purposes of this study were to determine the rate of concordance between diagnoses of infection made with frozen and permanent sections and to assess how discrepancies affected patient outcomes. A total of 282 samples from 62 patients were collected for frozen and permanent section analysis. There was concordance in 274 samples (97%). In 1 case, discrepancies led to retention of components during persistent infection, and the patient required further revision and antibiotics until infection free. Otherwise, discrepancies did not affect patient outcomes. There is good concordance between frozen and permanent sections for diagnosing periprosthetic hip infection and rarely do these discrepancies affect management.

Atraumatic osteonecrosis of the distal radius and ulna: case series and review.

PURPOSE: Atraumatic multifocal osteonecrosis is defined as the occurrence of atraumatic osteonecrosis in 3 or more anatomic locations, and it is rare. We identified 6 patients with osteonecrotic lesions in the distal ulna, radius, or both. The purposes of this study were to describe the clinical manifestations of atraumatic multifocal osteonecrosis affecting these bones, to identify risk factors for developing the disease in these locations, and to evaluate the success of treatment by percutaneous drilling. METHODS: A total of 10 wrists in 6 women with a mean age of 41 years had symptomatic osteonecrosis. Patients were treated by percutaneous drilling after they had failed nonoperative modalities. Clinical evaluation included preoperative and postoperative Michigan Hand Questionnaire scores plain radiographs, and MRI evaluations were performed to characterize the disease. The incidence of risk factors was recorded. RESULTS: There was disease occurrence in the radius in all 10 wrists and in the ulnas of 4 wrists. All patients presented with symptomatic osteonecrosis of the large joints (primarily knee or hip), presumably secondary to corticosteroid use. These patients later developed symptomatic pain in the distal ulna, radius, or both that impaired daily activities. Other risk factors included alcohol or tobacco use, blood dyscrasias, and systemic lupus erythematosus. Treatment consisted of percutaneous drilling of the distal radius (and ulna when affected). One patient required additional bilateral drillings and had further improvement in her Michigan Hand Questionnaire scores. At a mean follow up of 35 months, there was no disease progression as evident radiographically. CONCLUSIONS: The distal radius and ulna are rare sites of osteonecrosis associated with multifocal disease. The clinical presentation and risk factors are similar to osteonecrosis in the large joints. Magnetic resonance imaging identifies necrotic lesions. The present study suggests that disease in these sites can be safely and effectively treated with percutaneous drilling. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Chronic opioid use prior to total knee arthroplasty.

BACKGROUND: Chronic use of opioid medications may lead to dependence or hyperalgesia, both of which might adversely affect perioperative and postoperative pain management, rehabilitation, and clinical outcomes after total knee arthroplasty. The purpose of this study was to evaluate patients who underwent total knee arthroplasty following six or more weeks of chronic opioid use for pain control and to compare them with a matched group who did not use opioids preoperatively. METHODS: Forty-nine knees in patients who had a mean age of fifty-six years (range, thirty-seven to seventy-eight years) and who had regularly used opioid medications for pain control prior to total knee arthroplasty were compared with a group of patients who had not used them. Length of hospitalization, aseptic complications requiring reoperation, requirement for specialized pain management, and clinical outcomes were assessed for both groups. RESULTS: Knee Society scores were significantly lower in the patients who regularly used opioid medications at the time of final follow-up (mean, three years; range, two to seven years); the opioid group had a mean of 79 points (range, 45 to 100 points) as compared with a mean of 92 points (range, 59 to 100 points) in the non-opioid group. A significantly higher prevalence of complications was seen in the opioid group, with five arthroscopic evaluations and eight revisions for persistent stiffness and/or pain, compared with none in the matched group. Ten patients in the opioid group were referred for outpatient pain management, compared with one patient in the non-opioid group. CONCLUSIONS: Patients who chronically use opioid medications prior to total knee arthroplasty may be at a substantially greater risk for complications and painful prolonged recoveries. Alternative non-opioid pain medications and/or earlier referral to an orthopaedic surgeon prior to habitual opioid use should be considered for patients with painful degenerative disease of the knee.