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.

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.

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.

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.

Hip resurfacing in patients who have osteonecrosis and are 25 years or under.

BACKGROUND: Young patients with osteonecrosis (ON) treated with THA often have suboptimal function and radiographic failure with eventual revision. Resurfacing may be an option because of potentially increased functionality and decreased radiographic failure, although neither has been confirmed in the literature. QUESTIONS/PURPOSES: We therefore compared the clinical scores and radiographic failures of resurfacing patients 25 years or younger with osteonecrosis with those for patients with ON treated with THA. METHODS: We identified 17 patients (20 resurfaced hips) who were 25 years or younger and treated by resurfacing for ON. Mean followup was 62 months (range, 32-103 months). This group was matched by gender, age, BMI, and followup to 16 patients (20 hips) treated with THA with a mean 61 month followup (range, 34-88 months). Additionally, the group was compared to 78 patients (87 hips) with ON over age 25 who underwent resurfacing during the same time with a mean followup of 61 months (range, 27-112 months). RESULTS: The mean Harris score improved from 48 points preoperatively to 93 points with a 100% 7.5 year survivorship in the young resurfacing group. In the THA cohort, the mean score improved from 44 points preoperatively to 94 points postoperatively, with a 93.3% 7.5 year survivorship; similar to the results for all resurfacing patients. Radiographs did not reveal malalignment or progressive radiolucencies in any cohort. CONCLUSION: At approximately 5 year followup, young resurfacing patients were similar to other resurfacing patients and standard THA patients regarding clinical ratings and radiographic failures.

Total knee arthroplasty in patients over 80 years of age.

We conducted this study to review the clinical and radiographic outcomes of patients 80 years of age or older who underwent total knee arthroplasty (TKA). We identified clinical results in 60 patients (66 knees) who had a mean age of 84 years (range, 80 to 95 years) and who underwent TKA. These were compared with a non-age-matched group of 63 patients (66 knees) who had a mean age of 69 years (range, 60 to 79 years). Four patients were lost to follow-up. After a mean 43-month follow-up (range, 24 to 117 months), Knee Society pain and function scores for the study group improved from 53 points (range, 25 to 70 points) and 53 points (range, 40 to 70 points), respectively, to 94 points (range, 75 to 100 points) and 87 points (range, 45 to 100 points). There were no implant failures, 2 surgical complications, and 13 medical complications. In the matching group, there were four surgical complications (two required revision) and two medical complications. There were no radiographic failures or progressive radiolucencies. Although the incidence of medical complications in the perioperative period may be higher, TKA is a safe and effective treatment for refractory joint pain in patients over 80 years of age.

Excellent Clinical Outcomes in Total Knee Arthroplasty Performed Without a Tourniquet.

Although tourniquet use is the standard protocol for total knee arthroplasties it may lead to postoperative complications including thigh pain, compressive soft-tissue problems, and thromboembolic events. The purpose of this study was to explore the perioperative and clinical outcomes of total knee arthroplasty performed without a tourniquet. Thirty consecutive total knee arthroplasties were performed in 30 patients without a tourniquet and compared with 30 procedures (30 matched patients) performed with a tourniquet. Tourniquet patients had statistically lower mean intraoperative blood loss, total blood loss, and change in hematocrit, but these did not have any clinical impact or change the transfusion rate between the groups. At a mean follow-up of 3 years, both groups achieved excellent mean Knee Society scores with similar improvements between groups. There were no complications or radiographic abnormalities in either group. Total knee arthroplasty performed with or without a tourniquet yields similar intraoperative surgical and postoperative clinical outcomes.

Prophylactic oral antibiotics reduce reinfection rates following two-stage revision total knee arthroplasty.

The purpose of this study was to compare the incidence of reinfection in patients who received oral antibiotic prophylaxis with those who did not following two-stage revision knee arthroplasty. Additional purposes included: (1) comparison of these findings to the infection rate in patients who underwent revision for aseptic reasons, and (2) characterisation of the organisms responsible for reinfection following revision procedures. Twenty-eight two-stage revision knee arthroplasty procedures were followed up by a mean of 33 days of oral antibiotics (range, 28-43 days), while the remaining 38 procedures received only 24-72 hours of in-patient antibiotics. The incidence of reinfection in each group within 12 months was compared. The reinfection rates were additionally compared to those of 237 patients who underwent revision for aseptic loosening over the same time period. Patients who were treated with postoperative antibiotic prophylaxis had a considerably lower reinfection rate, with one reinfection in the prophylaxis group (4%), compared to six reinfections in the no-prophylaxis group (16%). The reinfection rates remained higher compared to those found in patients who underwent revision knee arthroplasty for aseptic loosening (1 of 237 patients; 0.4%). Both high and low virulence organisms were identified in the patients who were subsequently reinfected. A minimum of 28 days of postoperative oral antibiotics appeared to decrease reinfection rates following two-stage revision knee arthroplasty. These results suggest that the use of oral antibiotic prophylaxis following re-implantation may be appropriate in all patients undergoing two-stage revision, even in the absence of any signs of active infection.

Should gram stains have a role in diagnosing hip arthroplasty infections?

BACKGROUND: The utility of Gram stains in diagnosing periprosthetic infections following total hip arthroplasty has recently been questioned. Several studies report low sensitivity of the test, and its poor ability to either confirm or rule out infection in patients undergoing revision total hip arthroplasty. Despite this, many institutions including that of the senior author continue to perform Gram stains during revision total hip arthroplasty. QUESTIONS/PURPOSES: We assessed the sensitivity, specificity, accuracy, and positive and negative predictive values of Gram stains from surgical-site samplings taken from procedures on patients with both infected and aseptic revision total hip arthroplasties. METHODS: A review was performed on patients who underwent revision total hip arthroplasty between 2000 and 2007. Eighty-two Gram stains were performed on patients who had infected total hip arthroplasties and underwent revision procedures. Additionally, of the 410 revision total hip arthroplasties performed on patients who were confirmed infection-free, 120 Gram stains were performed. Patients were diagnosed as infected using multiple criteria at the time of surgery. Sensitivity, specificity, positive and negative predictive values, and accuracy were calculated from these Gram stain results. RESULTS: The Gram stain demonstrated a sensitivity and specificity of 9.8% and 100%, respectively. In this series, the Gram stain had a negative predictive value of 62%, a positive predictive value of 100%, and an accuracy of 63%. CONCLUSIONS: Gram stains obtained from surgical-site samples had poor sensitivity and poor negative predictive value. Based on these findings, as well as those of other authors, we believe that Gram stains should no longer be considered for diagnosing infections in revision total hip arthroplasty. LEVEL OF EVIDENCE: Level III, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

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.

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.].

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.

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.

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.