Mortality Rates After Nonoperative Geriatric Hip Fracture Treatment: A Matched Cohort Analysis.

OBJECTIVE: To compare the mortality rate between geriatric patients with hip fracture treated nonoperatively and a matched cohort treated operatively. DESIGN: Retrospective Observational Matched Cohort Study. SETTING: Academic Level 1 Trauma Center. PATIENTS: Geriatric patients who sustained femoral neck and intertrochanteric/peritrochanteric fractures, excluding isolated greater trochanteric fractures. All patients older than 65 years with hip fractures over a 10-year period were identified. Operative patients were matched at a 2:1 ratio, when possible, to nonoperative patients based on Charlson Comorbidity Index and American Society of Anesthesiologists score. INTERVENTION: Nonoperative treatment or operative treatment (femoral neck fractures: cannulated screw fixation or hemiarthroplasty; intertrochanteric/peritrochanteric fractures: sliding hip screw or cephalomedullary nail fixation; or proximal femoral locking plate). MAIN OUTCOMES: Mortality calculated at 30 and 90 days, and 1-year after injury. Mortality was compared between groups using logistic regression while controlling for age, CVA/TIA, and dementia. RESULTS: Seven hundred seventy-two patients (171 nonoperative and 601 operative) were initially identified. After applying the matching algorithm, 128 nonoperative and 239 operative patients were included in the analysis. There were no significant differences in age, sex, Charlson Comorbidity Index, or American Society of Anesthesiologists score between the cohorts. Nonoperative patients had a significantly higher 1-year mortality rate than operative patients [46.1% vs. 18.0%, Odds Ratio (95% confidence interval): 3.85 (2.34-6.41), P < 0.001]. CONCLUSIONS: Geriatric patients with hip fracture treated nonoperatively had a 1-year mortality rate of 46.1%, more than double the rate among operative patients. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Is the timing of fixation associated with fracture-related infection among tibial plateau fracture patients with compartment syndrome? A multicenter retrospective cohort study of 729 patients.

BACKGROUND: Tibial plateau fractures with an ipsilateral compartment syndrome are a clinical challenge with limited guidance regarding the best time to perform open reduction and internal fixation (ORIF) relative to fasciotomy wound closure. This study aimed to determine if the risk of fracture-related infection (FRI) differs based on the timing of tibial plateau ORIF relative to closure of ipsilateral fasciotomy wounds. METHODS: A retrospective cohort study identified patients with tibial plateau fractures and an ipsilateral compartment syndrome treated with 4-compartment fasciotomy at 22 US trauma centers from 2009 to 2019. The primary outcome measure was FRI requiring operative debridement after ORIF. The ORIF timing relative to fasciotomy closure was categorized as ORIF before, at the same time as, or after fasciotomy closure. Bayesian hierarchical regression models with a neutral prior were used to determine the association between timing of ORIF and infection. The posterior probability of treatment benefit for ORIF was also determined for the three timings of ORIF relative to fasciotomy closure. RESULTS: Of the 729 patients who underwent ORIF of their tibial plateau fracture, 143 (19.6%) subsequently developed a FRI requiring operative treatment. Patients sustaining infections were: 21.0% of those with ORIF before (43 of 205), 15.9% at the same time as (37 of 232), and 21.6% after fasciotomy wound closure (63 of 292). ORIF at the same time as fasciotomy closure demonstrated a 91% probability of being superior to before closure (RR, 0.75; 95% CrI, 0.38 to 1.10). ORIF after fasciotomy closure had a lower likelihood (45%) of a superior outcome than before closure (RR, 1.02; 95% CrI; 0.64 to 1.39). CONCLUSION: Data from this multicenter cohort confirms previous reports of a high FRI risk in patients with a tibial plateau fracture and ipsilateral compartment syndrome. Our results suggest that ORIF at the time of fasciotomy closure has the highest probability of treatment benefit, but that infection was common with all three timings of ORIF in this difficult clinical situation.

Reduction techniques for intramedullary nailing of tibial shaft fractures: a comparative study.

OBJECTIVES: To assess the impact of various reduction techniques on postoperative alignment following intramedullary nail (IMN) fixation of tibial shaft fractures. DESIGN: Retrospective comparative study. SETTING: Level I trauma center. PATIENTS: Four hundred twenty-eight adult patients who underwent IMN fixation of a tibial shaft fracture between 2008 and 2017. INTERVENTION: IMN fixation with use of one or more of the following reduction techniques: manual reduction, traveling traction, percutaneous clamps, provisional plating, or blocking screws. MAIN OUTCOME MEASURES: Immediate postoperative coronal and sagittal plane alignment, measured as deviation from anatomic axis (DFAA); coronal and sagittal plane malalignment (defined as DFAA >5° in either plane). RESULTS: Four hundred twenty-eight patients met inclusion criteria. Manual reduction (MR) alone was used in 11% of fractures, and adjunctive reduction aids were used for the remaining 89%. After controlling for age, BMI, and fracture location, the use of traveling traction (TT) with or without percutaneous clamping (PC) resulted in significantly improved coronal plane alignment compared to MR alone (TT: 3.4°, TT+PC: 3.2°, MR: 4.5°, P = .007 and P = .01, respectively). Using TT+PC resulted in the lowest rate of coronal plane malalignment (13% vs 39% with MR alone, P = .01), and using any adjunctive reduction technique resulted in decreased malalignment rates compared to MR (24% vs 39%, P = .02). No difference was observed in sagittal plane alignment between reduction techniques. Intraclass correlation coefficient (ICC) results indicated excellent intraobserver reliability on both planes (both ICC>0.85), good inter-observer reliability in the coronal plane (ICC = 0.7), and poor inter-observer reliability in the sagittal plane (ICC = 0.05). CONCLUSIONS: The use of adjunctive reduction techniques during IMN fixation of tibia fractures is associated with a lower incidence of coronal plane malalignment when compared to manual reduction alone. LEVEL OF EVIDENCE: Therapeutic Level III.

Association of Perioperative Computed Tomography Hounsfield Units and Failure of Femoral Neck Fracture Fixation.

OBJECTIVES: To determine whether Hounsfield units (HUs) measured on perioperative computed tomographic scans are associated with radiographic outcomes and reoperations after femoral neck fracture fixation. DESIGN: Retrospective cohort study. SETTING: Level I trauma center. PATIENTS: One hundred fourteen patients age ≥18 years, who presented to a Level I trauma center, and who underwent surgical fixation of intracapsular femoral neck fracture and had perioperative computed tomographic scans and adequate follow-up. INTERVENTION: None. MAIN OUTCOME MEASUREMENTS: Screw penetration, femoral neck shortening >5 mm, and revision surgery. RESULTS: A median follow-up was 23 months. An HU measurement of the femoral head was significantly associated with screw penetration and femoral neck shortening but not revision surgery. Patients with middle femoral head HU measurements <146 had 17 times (95% confidence interval: 4.32-78.9, P < 0.001) increased odds of screw penetration. Greater than 5 mm shortening was seen in patients with HUs <212.5 in the low head section by an odds ratio of 7.8 (95% confidence interval: 2.15-33.0, P = 0.014). CONCLUSION: Outcome differences regarding screw penetration and femoral neck shortening related to the HU or densities of femoral head and neck at the time of fracture are significant. These findings can help the clinician with developing a treatment plan for either arthroplasty or fixation of a femoral neck fracture based on objective bone quality measurements rather than relying on an arbitrary age recommendation. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Methicillin-Resistant Staphylococcus Aureus Carrier Rate in Orthopaedic Trauma Patients: A Prospective Cohort Study.

OBJECTIVES: To identify the methicillin-resistant Staphylococcus aureus (MRSA) carrier rate among surgical patients on an orthopaedic trauma service and to determine whether screening is an effective tool for reducing postoperative MRSA infection in this population. DESIGN: Prospective. SETTING: Level 1 trauma center. PATIENTS/PARTICIPANTS: Two hundred forty-eight patients with operatively managed orthopaedic trauma conditions during the study period. Two hundred three patients (82%) had acute orthopaedic trauma injuries. Forty-five patients (18%) underwent surgery for a nonacute orthopaedic trauma condition, including 36 elective procedures and 9 procedures to address infection. INTERVENTION: MRSA screening protocol, preoperative antibiotics per protocol. MAIN OUTCOME MEASUREMENTS: MRSA carrier rate, overall infection rate, MRSA infection rate. RESULTS: Our screening captured 71% (175/248) of operatively treated orthopaedic trauma patients during the study period. The overall MRSA carrier rate was 3.4% (6/175). When separated by group, the acute orthopaedic trauma cohort had an MRSA carrier rate of 1.4% (2/143), and neither MRSA-positive patient developed a surgical site infection. Only one MRSA infection occurred in the acute orthopaedic trauma cohort. The nonacute group had a significantly higher MRSA carrier rate of 12.5% (4/32, P = 0.01), and the elective group had the highest MRSA carrier rate of 15.4% (4/26, P < 0.01). The odds ratio of MRSA colonization was 10.1 in the nonacute group (95% confidence interval, 1.87-75.2) and 12.8 for true elective group (95% confidence interval, 2.36-96.5) when compared with the acute orthopaedic trauma cohort. CONCLUSIONS: There was a low MRSA colonization rate (1.4%) among patients presenting to our institution for acute fracture care. Patients undergoing elective surgery for fracture-related conditions such as nonunion, malunion, revision surgery, or implant removal have a significantly higher MRSA carrier rate (15.4%) and therefore may benefit from MRSA screening. Our results do not support routine vancomycin administration for orthopaedic trauma patients whose MRSA status is not known at the time of surgery. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Orthopaedic injuries from snowmobile accidents: a multi-centre analysis of demographics, injury patterns, and outcomes.

PURPOSE: More than 2 million people in North America use snowmobiles, resulting in an estimated 200 fatalities and 14,000 injuries annually. The purpose of this study is to document the demographics, orthopaedic injury patterns, and short-term outcomes of patients with snowmobile-related injuries. MATERIALS AND METHODS: A retrospective review was performed at two regional trauma centres in a region where snowmobile use is prevalent. Patients who sustained snowmobile-related injuries over a 12-year period were identified from the hospitals' trauma registries using E-codes (E820-E820.9). Patient demographics were recorded, as were injury characteristics including rates of substance use, open fractures, Injury Severity Score (ISS), Abbreviated Injury Score (AIS) for the extremities, and mortality. Rates of inpatient surgery, as well as hospital and ICU length of stay (LOS), were also recorded. RESULTS: We identified 528 patients with snowmobile-related injuries. Average age was 37 years, and 418 patients (79%) were male. Eighty-eight per cent of all patients with snowmobile injuries were admitted to the hospital with an average LOS of 5.7 days. Among those admitted to the hospital, average ISS was 12.3, and 28% of these patients had ISS > 15. A total of 261 patients (56%) suffered extremity injuries (including 163 upper and 173 lower extremity fractures) with an average extremity AIS of 2.4. There were 700 total fractures (1.5 per patient), and 9% of all fractures were open. A total of 208 patients (45%) suffered head injuries, and 132 patients (28%) sustained vertebral column fractures. A total of 201 patients (43%) required inpatient surgery, and eight patients (1.7%) sustained fatal injuries. CONCLUSIONS: We present a detailed multi-centre analysis of orthopaedic injury patterns and outcomes resulting from snowmobile-related injuries. Patients injured while snowmobiling share similar injury patterns with patients injured in motorcycle and other high-energy motor vehicle accidents.

A Reliable and Reproducible Critical-Sized Segmental Femoral Defect Model in Rats Stabilized with a Custom External Fixator.

Orthopedic research relies heavily on animal models to study mechanisms of bone healing in vivo as well as investigate the new treatment techniques. Critical-sized segmental defects are challenging to treat clinically, and research efforts could benefit from a reliable, ambulatory small animal model of a segmental femoral defect. In this study, we present an optimized surgical protocol for the consistent and reproducible creation of a 5 mm critical diaphyseal defect in a rat femur stabilized with an external fixator. The diaphyseal ostectomy was performed using a custom jig to place 4 Kirschner wires bicortically, which were stabilized with an adapted external fixator device. An oscillating bone saw was used to create the defect. Either a collagen sponge alone or a collagen sponge soaked in rhBMP-2 was implanted into the defect, and the bone healing was monitored over 12 weeks using radiographs. After 12 weeks, rats were sacrificed, and histological analysis was performed on the excised control and treated femurs. Bone defects containing only collagen sponge resulted in non-union, while rhBMP-2 treatment yielded the formation of a periosteal callous and new bone remodeling. Animals recovered well after implantation, and external fixation proved successful in stabilizing the femoral defects over 12 weeks. This streamlined surgical model could be readily applied to study bone healing and test new orthopedic biomaterials and regenerative therapies in vivo.

Comparison of Dorsal Dermal Fascial Fenestrations With Fasciotomy in an Acute Compartment Syndrome Model in the Foot.

BACKGROUND: Treatment of compartment syndrome of the foot with fasciotomy remains controversial because of the theoretical risk of infection and soft tissue coverage issues. The purpose of this study was to evaluate the efficacy of compartment decompression with dorsal dermal fascial fenestration compared with fasciotomy in a cadaveric foot compartment syndrome model. We hypothesized that fasciotomies and dorsal dermal fenestrations would provide equivalent compartment decompression. METHODS: Intracompartmental pressure was monitored in the first dorsal interosseous (FDIO), abductor (ABD), and superficial plantar (SP) compartments of 10 fresh frozen cadaveric limbs. A compartment syndrome model was created. Pressure measurements were obtained after dorsal dermal fascial fenestrations and after formal fasciotomies. Primary outcome variables were intracompartmental pressure in the FDIO, ABD, and SP compartments for 4 specific conditions: (1) baseline pressure, (2) pressure after compartment syndrome, (3) pressure after dermal fascial fenestrations, and (4) pressure after fasciotomies. RESULTS: Fasciotomies decreased compartment pressures to within 10 mm Hg of baseline in all compartments (P < .001). Compared with fasciotomies, dorsal dermal fascial fenestrations decreased the average pressure only in the FDIO compartment. Pressure decreases after fasciotomies compared with dorsal dermal fascial fenestrations were significantly greater (P < .005). CONCLUSION: Fasciotomies were more effective than dorsal dermal fascial fenestrations at decreasing intracompartmental pressure. It seems that dermal fascial fenestrations were unable to provide effective decompression of the ABD and SP compartments of the foot and could provide only partial decompression of the dorsal compartments. CLINICAL RELEVANCE: The findings of this study indicate the need for caution in using fenestrations alone to treat acute compartment syndrome of the foot.

Intracompartmental Pressure Monitoring Using a Handheld Pressure Monitoring System.

INTRODUCTION: We describe the correct technique for measuring compartment pressure with a handheld device to diagnose compartment syndrome. STEP 1 DEVICE PREPARATION: Proper preparation of the handheld pressure monitoring device (Stryker Surgical, Kalamazoo, Michigan) is critical to ensure that the device performs appropriately. STEP 2 IDENTIFICATION OF THE COMPARTMENT OF INTEREST: The needle must be placed in the proper location to appropriately measure a compartment's pressure. STEP 3 INJECTION: Inject saline solution from the pressure monitoring device to clear any soft tissue from the side port on the needle that could result in inaccurate pressure measurements. STEP 4 STABILIZATION AND PRESSURE READING: The pressure must reach a stable state before it is recorded; different pressure thresholds for decompression have been recommended in the literature. STEP 5 REPEAT MEASUREMENTS: As mistakes can be made with any single measurement, accuracy may be improved by repeating steps 1 through 4 and averaging the results. STEP 6 ADDITIONAL COMPARTMENTS: After the reading is obtained, move on to any additional compartment(s) that need to be evaluated, repeating the steps listed above. RESULTS: The handheld intracompartmental monitoring device with a side-ported needle has been shown to be extremely accurate in the laboratory.IndicationsContraindicationsPitfalls & Challenges.

Do one-time intracompartmental pressure measurements have a high false-positive rate in diagnosing compartment syndrome?

BACKGROUND: Intracompartmental pressure measurements are frequently used in the diagnosis of compartment syndrome, particularly in patients with equivocal or limited physical examination findings. Little clinical work has been done to validate the clinical use of intracompartmental pressures or identify associated false-positive rates. We hypothesized that diagnosis of compartment syndrome based on one-time pressure measurements alone is associated with a high false-positive rate. METHODS: Forty-eight consecutive patients with tibial shaft fractures who were not suspected of having compartment syndrome based on physical examinations were prospectively enrolled. Pressure measurements were obtained in all four compartments at a single point in time immediately after induction of anesthesia using a pressure-monitoring device. Preoperative and intraoperative blood pressure measurements were recorded. The same standardized examination was performed by the attending surgeon preoperatively, postoperatively, and during clinical follow-up for 6 months to assess clinical evidence of acute or late compartment syndrome. RESULTS: No clinical evidence of compartment syndrome was observed postoperatively or during follow-up until 6 months after injury. Using the accepted criteria of delta P of 30 mm Hg from preoperative diastolic blood pressure, 35% of cases (n = 16; 95% confidence interval, 21.5-48.5%) met criteria for compartment syndrome. Raising the threshold to delta P of 20 mm Hg reduced the false-positive rate to 24% (n = 11; 95% confidence interval, 11.1-34.9%). Twenty-two percent (n = 10; 95% confidence interval, 9.5-32.5%) exceeded absolute pressure of 45 mm Hg. CONCLUSION: A 35% false-positive rate was found for the diagnosis of compartment syndrome in patients with tibial shaft fractures who were not thought to have compartment syndrome by using currently accepted criteria for diagnosis based solely on one-time compartment pressure measurements. Our data suggest that reliance on one-time intracompartmental pressure measurements can overestimate the rate of compartment syndrome and raise concern regarding unnecessary fasciotomies. LEVEL OF EVIDENCE: Diagnostic study, level II.

Can intramuscular glucose levels diagnose compartment syndrome?

BACKGROUND: Compartment syndrome is difficult to diagnose, particularly in patients who are not able to undergo adequate clinical examination. Current methods rely on pressure measurements within the compartment, have high false-positive rates, and do not reliably indicate presence of muscle ischemia. We hypothesized that measurement of intramuscular glucose and oxygen can identify compartment syndrome with high sensitivity and specificity. METHODS: Compartment syndrome was created in 12 anesthetized adult mixed-sex beagles, in the craniolateral compartment of a lower leg, by infusion of lactated Ringer's solution with normal serum concentration of glucose. The contralateral leg served as a control. Hydrostatic pressure, oxygen tension, and glucose concentration were recorded with commercially available probes. Compartment syndrome was maintained for 8 hours, and the animals were recovered. Two weeks later, compartment and control legs underwent muscle biopsy. Specimens were reviewed by a blinded pathologist. RESULTS: Within 15 minutes of creating compartment syndrome, glucose concentration and oxygen tension in the experimental limb were significantly lower than in the control limb (glucose, p = 0.02; oxygen, p = 0.007; two-tailed t test). Intramuscular glucose concentration of less than 97 mg/dL was 100% sensitive (95% confidence interval [CI], 73-100%) and 75% specific (95% CI, 40-94%) for the presence of compartment syndrome. Partial pressure of oxygen less than 30 mm Hg was 100% sensitive (95% CI, 72-100%) and 100% specific (95% CI, 69-100%) for the presence of compartment syndrome. Pathology confirmed compartment syndrome in all experimental limbs. CONCLUSION: Our results show that intramuscular glucose concentration and partial pressure of oxygen rapidly identify muscle ischemia with high sensitivity and specificity after experimentally created compartment syndrome in this animal model.

How much vertical displacement of the symphysis indicates instability after pelvic injury?

BACKGROUND: Measures of pubic symphyseal widening are used by at least two classification systems as determinants of injury grade. Recent work has challenged the commonly used parameter of 2.5 cm of pubic symphysis as an accurate marker of pelvic injury grade and has suggested a role of rotation in the flexion-extension plane as a determinant of pelvic stability. We investigated pelvic stability in the flexion-extension plane to determine a threshold of rotational displacement of the hemipelvis above which the potential for instability exists. METHODS: Cadaveric specimens were mounted onto a servohydraulic biaxial testing machine and subjected to a vertically directed flexion moment. Position of hemipelvis was recorded using a three-dimensional motion capture system and video recording. Displacement of the pubic symphysis and changes in length and position of the sacrospinous and sacrotuberous ligaments were recorded. Amount of force applied was measured and recorded. A yield point was determined as the first point at which the force plot exhibited a decrease in force and was correlated to the corresponding displacement. RESULTS: The mean vertical displacement of the pubic symphysis at the yield point was 16 mm (95% confidence interval, 11-22 mm). Mean sacrospinous ligament strain at yield point was 4% (range, 1.0-9.5%). CONCLUSION: Pelves with vertical rotational symphyseal displacement of less than 11 mm can reasonably be expected to have rotational stability in the flexion-extension plane. Those with displacement of greater than 22 mm can be expected to have lost some integrity regarding resistance to pelvic flexion. These values may allow clinicians to infer pelvic stability from amount of vertical symphyseal displacement.

A biomechanical comparison of a locking plate, a nail, and a 95° angled blade plate for fixation of subtrochanteric femoral fractures.

OBJECTIVE: To compare the biomechanical performance of a cephalomedullary nail (CMN), a proximal femoral locking plate, and a 95° angled blade plate in a comminuted subtrochanteric fracture model. METHODS: A comminuted subtrochanteric femoral fracture model was created with a 2-cm gap below the lesser trochanter in 15 pairs of human cadaveric femora confirmed to be nonosteoporotic. The femora were randomized to treatment with one of the previously mentioned 3 devices. Each was tested under incrementally increasing cyclic load up to 90,000 cycles from 50% to 250% of body weight to simulate progressive weight bearing during 3 months of an average 700-N (approximately, 70 kg or 150 lb) person. Force, number of cycles, and total load sustained to reach 10 mm of displacement were compared. Failure modes were also noted. RESULTS: The CMN construct withstood significantly more cycles, failed at a significantly higher force, and withstood a significantly greater load than either of the plate constructs (P < 0.001). Varus collapse was significantly lower in the CMN construct (P < 0.0001). Modes of failure differed among implant-bone constructs with damage to the femoral head through implant cutout in 5 of 10 blade plate specimens and 2 of 10 CMN specimens, whereas no damage to the femoral head bone was observed in any of the locking plate constructs. CONCLUSIONS: The CMN construct was biomechanically superior to either the locking plate or 95° blade plate constructs. The locking plate construct was biomechanically equivalent to the blade plate construct.

Does 2.5 cm of symphyseal widening differentiate anteroposterior compression I from anteroposterior compression II pelvic ring injuries?

OBJECTIVE: It has been proposed that 2.5 cm of diastasis of the symphysis pubis corresponds with injury to the anterior sacroiliac ligament and differentiates Young-Burgess anteroposterior compression Type I and II pelvic ring injuries. We hypothesized that if a pelvis has greater than 2.5 cm of symphysis pubis diastasis, the anterior sacroiliac ligaments are disrupted and the pelvic floor has failed. METHODS: Pure torsional moment was applied to cadaveric human pelves with the hemipelvis either unconstrained (n = 10) or constrained to move only in the plane of rotation (n = 10). We recorded displacement of the symphysis pubis and sacroiliac joint and the applied torque that corresponded with failure of the anterior sacroiliac ligaments. RESULTS: Average symphysis pubis diastasis at the point of anterior sacroiliac ligament failure was 2.2 cm (n = 20; range, 1-4.5 cm); however, 80% of the values were outside the range of 2 to 3 cm. Symphysis pubis diastasis in male specimens averaged 2.5 cm and in female specimens, 1.8 cm (P = 0.06). The sacrospinous and sacrotuberous ligaments that make up the pelvic floor were not injured in unconstrained testing (zero of 10 specimens) but were at least attenuated in constrained testing (10 of 10 specimens), either simultaneously or after anterior sacroiliac ligament failure. CONCLUSIONS: We were not able to confirm 2.5 cm of symphysis pubis diastasis as a valid differentiation point between anteroposterior compression I and II injuries because significant morphologic variation seems to exist. Our data support that anterior sacroiliac ligament disruption is likely for displacement greater than 4.5 cm and unlikely for values less than 1.8 cm. Our study suggests that sacrospinous and sacrotuberous ligaments might not rupture at the same time as the anterior sacroiliac ligament.

Hospital volume and inpatient mortality outcomes of total hip arthroplasty in the United States.

The purpose of this study was to examine the effect of hospital volume on outcomes for primary and revision total hip arthroplasty (THA). The Nationwide Inpatient Sample database was used to identify our patient set. These data include a sample of non-Medicare and Medicare patients who are unique to this study, increasing external validity compared with other studies. Outcome variables examined included in-hospital mortality and prolonged length of stay (PLOS). Primary THA mortality was 0.16% in the highest volume quartile and 0.29% in the lowest volume quartile (P < .001). The rates of PLOS showed improved outcomes in the highest volume hospitals. Similar trends were found for revision THA, with an in-hospital mortality of 1.20% for lowest volume hospitals and 0.48% for highest volume hospitals (P < .001). Hospitals with higher volume had superior inpatient outcomes mortality, PLOS, and discharge disposition for THA and revision arthroplasty.

Factitious disorders.

Factitious disorders reside under the broad umbrella of dysfunctional syndromes. This article is meant specifically to focus on common patterns of upper extremity factitious illness. It is intended to emphasize recognition, differential diagnosis, and problems related to misdiagnosis. It is not devoted to treatment, which is a separate issue.

Complex regional pain syndrome type I in the upper extremity.

Complex regional pain syndrome (CRPS) remains a challenging condition for physicians to treat since the earliest descriptions dating back to the Civil War. It has been most commonly reported after traumatic injury or fracture; however, many other causes have been documented. This article focuses on CRPS type 1 as it pertains to the upper extremity. In general, patients who have complex regional pain syndrome suffer from pain, sensory changes, edema, sweating, and temperature disturbance in the afflicted extremity. Chronic changes can involve the skin, nails, and bone. The pathophysiology of this condition remains unclear and is probably multifactorial, involving persistent inflammation, the sympathetic nervous system, the central nervous system and external stimuli. Treatment should be based on a multidisciplinary experienced team approach that is focused on functional restoration. Future research will provide insight into pathophysiology and optimal treatment regimens.

Fibromyalgia and myofascial pain syndromes and the workers' compensation environment: an update.

Fibromyalgia and myofascial pain syndromes are terms used to describe a constellation of complaints ranging from generalized aches to specific tender trigger points often accompanied by fatigue, depression, and sleep disturbances. In the past 5 years, research has been directed primarily at determining the pathophysiology of fibromyalgia and myofascial pain syndromes and the treatment of patients' comorbidities to alleviate their symptomatology. Controversy exists as to whether fibromyalgia and myofascial pain syndromes represent a specific pathology or are merely terms to describe clinical conditions that provide patients with the reassurance that their symptoms are real and help clinicians with therapeutic direction. In the occupational health setting, this uncertainty can lead to significant difficulty in determining short- and long-term disability and assigning culpability to an individual's work environment.