Comparison of Postoperative Anatomy Using Anatomic Total Shoulder Arthroplasty Versus Soft-Tissue Balancing Total Shoulder Arthroplasty.

BACKGROUND: The importance of anatomic reconstruction of the proximal humerus on shoulder biomechanics and kinematics after anatomic total shoulder replacement (aTSR) has been highlighted by a number of investigations. The humeral head designs of current-generation shoulder arthroplasty emphasize either anatomic or soft-tissue balancing total shoulder arthroplasty (sbTSR) philosophies. The purpose of this study was to compare the postoperative anatomy of TSR systems used to treat primary glenohumeral osteoarthritis. METHODS: This was a matched cohort study of 60 patients treated with either press-fit aTSR or sbTSR by two shoulder surgeons. The analysis of postoperative true AP radiographs was performed to calculate multiple representative anatomic parameters of the TSR. RESULTS: A significant difference was observed in the average measurements between the sbTSR and aTSR designs about the humeral head center offset (5.2 ± 0.4 mm versus 3.9 ± 0.3 mm; P = 0.02), implant-humeral shaft angle (0.3 ± 0.3 varus versus 1.7 ± 0.3 valgus, P < 0.001), and humeral head to tuberosity height (8.8 ± 0.4 mm versus 6.2 ± 0.4, P < 0.001), respectively. No significant difference was observed in the average measurements between the two systems' designs regarding the head-shaft angle (133.4° ± 0.8° versus 135.0° ± 1.0°, P = 0.16) and the relation of humeral head to lateral humeral cortex (0.15 ± 0.6 mm inside the lateral cortex versus 0.19 ± 0.6 outside the lateral cortex; P = 0.69), respectively. CONCLUSIONS: Despite differing design philosophies of these systems, and some notable differences, the absolute differences between the measured anatomic parameters were small and not likely clinically relevant. Anatomic and soft-tissue balancing humeral arthroplasty implants can both reliably reconstruct proximal humeral anatomy.

Cost-Minimization Analysis and Treatment Trends of Surgical and Nonsurgical Treatment of Proximal Humerus Fractures.

PURPOSE: Recent evidence demonstrated similar outcomes between nonsurgical and surgical management of displaced proximal humerus fractures. We analyzed treatment trends and performed a cost-minimization analysis comparing nonsurgical treatment, open reduction and internal fixation, reverse total shoulder arthroplasty, and hemiarthroplasty. We hypothesized that rates of surgical treatment have increased and that the costs associated with surgery are greater compared with nonsurgical management of proximal humerus fractures. METHODS: We used a US private-payer claims database of 22 million patient records from 2007 to 2016 to compare (1) cost for the episode of care from the payer perspective between each surgical group and nonsurgical treatment of proximal humerus fractures, and (2) annual trends and complication rates of each group. Cost data, including facility fees, physician fees, physical therapy, and clinic visits, were used to complete a cost-minimization analysis. RESULTS: Nonsurgical treatment was associated with lower average total costs compared with surgical intervention. Facility and physician fees accounted for most of this difference. Physical therapy costs and number of physical therapy visits were higher in each surgical group compared with nonsurgical treatment. Surgical treatment was associated with higher complications, revision rates, and length of stay. There was a small but statistically significant decrease in nonsurgical management of proximal humerus fractures between 2007 and 2016. No change was observed in rates of open reduction and internal fixation, whereas rates of reverse total shoulder arthroplasty increased and rates of hemiarthroplasty decreased. CONCLUSIONS: Nonsurgical management of proximal humerus fractures decreased during the study period. In the setting of treatment equipoise, cost-minimization analysis favors nonsurgical management of proximal humerus fractures. Surgical management is associated with higher complication rates, revision rates, and length of stay. TYPE OF STUDY/LEVEL OF EVIDENCE: Economic Decision Analysis IV.

Editorial Commentary: Augmenting Suture Anchor Fixation: Why Has It Not Caught on?

Biomechanical studies with reliable clinical applicability are challenging to carry out. The results can be heavily dependent on the materials being tested (condition and ages of specimens), environmental conditions (temperature, moisture), magnitude and direction of loading, loading characteristics (static, dynamic), loading cycles and frequency, and how one measures and defines failure. The interested reader gains more confidence in the results and recommendations of a biomechanics study if the methodology reasonably models real-world scenarios and multiple studies from different labs all come to the same general conclusion.

Development of a novel murine femur fracture and fixation model.

BACKGROUND: Animal models have been used for decades to simulate human fractures in the laboratory setting. Fracture models in mice are attractive because they offer a high volume, relatively low-cost method of investigating fracture healing characteristics. We report on the development of a novel murine femur fracture model that is rapid, reproducible and inexpensive. METHODS: As part of a pilot study to investigate the effects of smoking on fracture healing, fifteen 35-43 g twelve-week old female CD-1 mice underwent a novel surgical protocol using direct visualization of femur fracture creation and fixation. Following surgery, mice were sacrificed at 14 days, 28 days and 42 days. After sacrifice, the femora were analyzed using MicroCT and histology to evaluate progression of healing. RESULTS: Of the 14 mice that survived the surgical procedure (one succumbed to a complication of anesthesia), two lost reduction and did not heal. Histology demonstrated at 14 days 44.1% (SD±2.9%) of callus composed of cartilage. At 28 days there was 19.0% (SD±3.4%) of callus composed of cartilage. At 42 days there was 8.4% (SD±2.6%) callus composed of cartilage (p < 0.005). MicroCT demonstrated that from 14 to 42 days the average callus volume decreased from 101.6 mm3 to 68.2 mm3 while the relative bone volume of callus increased from 14 to 42 days (15%-31%) (p = 0.068). CONCLUSIONS: Our novel fracture and fixation model is an effective, rapid, reproducible and inexpensive method to simulate a fracture in a laboratory setting. Additionally, our model reliably creates a reproducible progression of radiographic and histological bone healing.

Can the FEAR Index Be Used to Predict Microinstability in Patients Undergoing Hip Arthroscopic Surgery?

BACKGROUND: Atraumatic hip instability, or microinstability, is a challenging diagnosis for clinicians to make. Several radiographic parameters have been proposed to help identify patients with instability as a means to direct treatment. The Femoro-epiphyseal Acetabular Roof (FEAR) index was recently offered as a parameter to predict instability in a borderline dysplastic population. PURPOSE: To evaluate the FEAR index in a series of predominantly nondysplastic patients undergoing hip arthroscopic surgery to determine if it can accurately predict patients with diagnosed microinstability at the time of surgery. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: A consecutive series of 200 patients undergoing hip arthroscopic surgery were evaluated for microinstability intraoperatively. Microinstability was diagnosed based on previously published criteria. Retrospectively, radiographic parameters were measured including the lateral center edge angle of Wiberg (LCEA), Tönnis angle, physeal scar angle, and FEAR index. Patients were excluded if they previously had any type of bony procedures performed, underwent prior open hip surgery or total hip arthroplasty of the ipsilateral hip, had osteoarthritis (Tönnis grade >1), or had any radiographic features of moderate-to-severe acetabular dysplasia including an LCEA <18°. RESULTS: After applying exclusion criteria, 167 hips in 150 patients were analyzed. Based on an intraoperative assessment, 96 hips (57.5%) were considered stable, and 71 hips (42.5%) had signs of microinstability (unstable group). Patients in the unstable group had fewer radiographic findings of femoroacetabular impingement and higher rates of borderline dysplasia. All 4 measured angles were found to have excellent interobserver agreement. The FEAR index was significantly more positive in the unstable group compared with the stable group (-7.8° vs -11.3°, respectively; P = .004). A more positive FEAR index was also found in patients meeting intraoperative criteria for instability, with the exception of chondral wear pattern. Unstable nondysplastic patients (LCEA ≥25°, Tönnis angle ≤10°) also were found to have higher FEAR index values (-9.0° vs -12.0°, respectively; P = .012). A FEAR index cut-off of -5.0° was associated with a specificity of 92.4% and accuracy of 69.4% for predicting instability in a nondysplastic population. CONCLUSION: The FEAR index was validated to improve the recognition of unstable patients preoperatively across a population with both borderline dysplastic and nondysplastic features.

Lower Complication Rate Following Ankle Fracture Fixation by Orthopaedic Surgeons Versus Podiatrists.

INTRODUCTION: Increased overlap in the scope of practice between orthopaedic surgeons and podiatrists has led to increased podiatric treatment of foot and ankle injuries. However, a paucity of studies exists in the literature comparing orthopaedic and podiatric outcomes following ankle fracture fixation. METHODS: Using an insurance claims database, 11,745 patients who underwent ankle fracture fixation between 2007 and 2015 were retrospectively evaluated. Patient data were analyzed based on the provider type. Complications were identified by the International Classification of Diseases, Ninth Revision, codes, and revision surgeries were identified by the Current Procedural Terminology codes. Complications analyzed included malunion/nonunion, infection, deep vein thrombosis, and rates of irrigation and débridement. Risk factors for complications were compared using the Charlson Comorbidity Index. RESULTS: Overall, 11,115 patients were treated by orthopaedic surgeons and 630 patients were treated by podiatrists. From 2007 to 2015, the percentage of ankle fractures surgically treated by podiatrists had increased, whereas that treated by orthopaedic surgeons had decreased. Surgical treatment by podiatrists was associated with higher malunion/nonunion rates among all types of ankle fractures. No differences in complications were observed in patients with unimalleolar fractures. In patients with bimalleolar or trimalleolar fractures, treatment by a podiatrist was associated with higher malunion/nonunion rates. Patients treated by orthopaedic surgeons versus podiatrists had similar comorbidity profiles. DISCUSSION: Surgical treatment of ankle fractures by orthopaedic surgeons was associated with lower rates of malunion/nonunion when compared with that by podiatrists. The reasons for these differences are likely multifactorial but warrants further investigation. Our findings have important implications in patients who must choose a surgeon to surgically manage their ankle fracture, as well as policymakers who determine the scope of practice. LEVEL OF EVIDENCE: Level III-retrospective cohort study.

Arthroscopic Technique for Treating Patella and Femoral Condyle Lesions With DeNovo Natural Tissue Allograft.

Use of juvenile particulate cartilage allograft has been previously described for the treatment of full-thickness chondral lesions of the knee. Although this procedure has traditionally been performed with an open approach, it can be performed using arthroscopic techniques with the potential for less morbidity and accelerated rehabilitation. This article describes an all-arthroscopic technique for treating patella and femoral condyle lesions with DeNovo Natural Tissue allograft, including clinical indications and a rehabilitation protocol.

Complication rates by surgeon type after open treatment of distal radius fractures.

BACKGROUND: In distal radius fracture repair, complications often lead to reoperation and increased cost. We examined the trends and complications in open reduction internal fixation of distal radius fractures across hand specialist and non-hand specialist surgeons. METHODS: We examined claims data from the Humana administrative claims database between 2007 and 2016. International Classification of Disease, 9th Edition and Current Procedural Terminology codes were searched related to distal radius fractures repaired by open reduction internal fixation. Patients were filtered based on initial treatment by a hand specialty or non-hand specialty surgeon. Complications were reported within 1 year of surgical treatment in the following distinct categories: non-union, malunion, extensor/flexor tendon repair, CRPS, infection. Descriptive statistics were reported. RESULTS: Hand specialists accounted for 182 procedures compared with 7708 procedures by non-hand specialty orthopaedic or general surgeons. There was an increase in the total number of procedures performed by hand specialists across the years of study, with a higher percentage of intra-articular cases completed by hand specialists (80.7%) compared to non-hand specialists (70.1%). Overall, the complication rates of hand specialists (6.5%) were higher than that of non-specialists (4.7%). CONCLUSIONS: The results of this study demonstrate a small difference in overall complications for open reduction internal fixation of distal radius fractures by hand specialists in comparison to non-specialists despite treating a higher percentage of intra-articular fractures. Future work controlling for factors unaccounted for in claims-based analyses, such as fracture complexity, patient comorbidities, and surgeon factors are needed. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Diagnostic Accuracy of 3 Physical Examination Tests in the Assessment of Hip Microinstability.

BACKGROUND: Hip microinstability is a diagnosis gaining increasing interest. Physical examination tests to identify microinstability have not been objectively investigated using intraoperative confirmation of instability as a reference standard. PURPOSE: To determine the test characteristics and diagnostic accuracy of 3 physical examination maneuvers in the detection of hip microinstability. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: A review was conducted of 194 consecutive hip arthroscopic procedures performed by a sports medicine surgeon at a tertiary-care academic center. Physical examination findings of interest, including the abduction-hyperextension-external rotation (AB-HEER) test, the prone instability test, and the hyperextension-external rotation (HEER) test, were obtained from prospectively collected data. The reference standard was intraoperative identification of instability based on previously published objective criteria. Test characteristics, including sensitivity, specificity, positive and negative predictive values, and accuracy, were calculated for each test as well as for combinations of tests. RESULTS: A total of 109 patients were included in the analysis. The AB-HEER test was most accurate, with a sensitivity of 80.6% (95% CI, 70.8%-90.5%) and a specificity of 89.4% (95% CI, 80.5%-98.2%). The prone instability test had a low sensitivity (33.9%) but a very high specificity (97.9%). The HEER test performed second in both sensitivity (71.0%) and specificity (85.1%). The combination of multiple tests with positive findings did not yield significantly greater accuracy. All tests had high positive predictive values (range, 86.3%-95.5%) and moderate negative predictive values (range, 52.9%-77.8%). When all 3 tests had positive findings, there was a 95.0% (95% CI, 90.1%-99.9%) chance that the patient had microinstability. CONCLUSION: The AB-HEER test most accurately predicted hip instability, followed by the HEER test and the prone instability test. However, the high specificity of the prone instability test makes it a useful test to "rule in" abnormalities. A positive result from any test predicted hip instability in 86.3% to 90.9% of patients, but a negative test result did not conclusively rule out hip instability, and other measures should be considered in making the diagnosis. The use of these tests may aid the clinician in diagnosing hip instability, which has been considered a difficult diagnosis to make because of its dynamic nature.

Hip arthroscopy in the United States: an update following coding changes in 2011.

The purpose of this study is to define the incidence of hip arthroscopy-related procedures in the United States prior to and following 2011 and to determine if the rise in incidence has coincided with an increase in the complexity and diversity of procedures performed. Patients who underwent hip arthroscopy were identified from a publicly available US database. A distinction was made between 'traditional' and 'extended' codes. CPT-29999 (unlisted arthroscopy) was considered extended and counted only if associated with a hip pathology diagnosis. Codes directed toward femoroacetabular impingement pathology were also considered extended codes and were analyzed separately based on increased technical skill. Unpaired student t-tests and z-score tests were performed. From 2007 to 2014, there were a total of 2581 hip arthroscopies performed in the database (1.06 cases per 10 000 patients). The number of hip arthroscopies increased 117% from 2007 to 2014 (P < 0.001) and 12.5% from 2011 to 2014 (P = 0.045). Hip arthroscopies using extended codes increased 475% from 2007 to 2014 (P < 0.001) compared to 24% for traditional codes (P < 0.001). Codes addressing femoroacetabular impingement (FAI) pathology increased 55.7% between 2011 to 2014 (P < 0.001). The ratio of labral repair to labral debridement in patients younger than 50 years exceeded >1.0 starting in 2011 (P < 0.001). The total number of hip arthroscopies in addition to the complexity and diversity of hip arthroscopy procedures performed in the United States continues to rise. FAI-based procedures and labral repairs are being performed more frequently in younger patients, likely reflecting both improved technical ability and current evidence-based research.

Cost-minimization Analysis of the Management of Acute Achilles Tendon Rupture.

BACKGROUND: Outcomes of nonsurgical management of acute Achilles tendon rupture have been demonstrated to be noninferior to those of surgical management. We performed a cost-minimization analysis of surgical and nonsurgical management of acute Achilles tendon rupture. METHODS: We used a claims database to identify patients who underwent surgical (n = 1,979) and nonsurgical (n = 3,065) management of acute Achilles tendon rupture and compared overall costs of treatment (surgical procedure, follow-up care, physical therapy, and management of complications). Complication rates were also calculated. Patients were followed for 1 year after injury. RESULTS: Average treatment costs in the year after initial diagnosis were higher for patients who underwent initial surgical treatment than for patients who underwent nonsurgical treatment ($4,292 for surgical treatment versus $2,432 for nonsurgical treatment; P < 0.001). However, surgical treatment required fewer office visits (4.52 versus 10.98; P < 0.001) and less spending on physical therapy ($595 versus $928; P < 0.001). Rates of rerupture requiring subsequent treatment (2.1% versus 2.4%; P = 0.34) and additional costs ($2,950 versus $2,515; P = 0.34) were not significantly different regardless whether initial treatment was surgical or nonsurgical. In both cohorts, management of complications contributed to approximately 5% of the total cost. CONCLUSION: From the payer's perspective, the overall costs of nonsurgical management of acute Achilles tendon rupture were significantly lower than the overall costs of surgical management. LEVEL OF EVIDENCE: III, Economic Decision Analysis.

Complication Rates for Hip Arthroscopy Are Underestimated: A Population-Based Study.

PURPOSE: To identify major and minor complication rates associated with hip arthroscopy from a payer-based national database and compare with the rates reported in the existing literature. METHODS: Patients who underwent hip arthroscopy between 2007 and 2014 were identified using PearlDiver, a publicly available database. Rates of major and minor complications, as well as conversion to total hip arthroscopy (THA), were determined by using Current Procedural Terminology (CPT) and International Classification of Diseases, Ninth Revision (ICD-9), codes. Incidence rates of select major complications across the entire database were used as a comparison group. Statistical significance was set at P < .05. RESULTS: Of 18 million patients screened from 2007 to 2014, a total of 2,581 hip arthroscopies were identified. The rates of major and minor complications within a 1-year postoperative period were 1.74% and 4.22%, respectively. Complications included heterotopic ossification (2.85%), bursitis (1.23%), proximal femur fracture (1.08%), deep vein thrombosis (0.79%), and hip dislocation (0.58%). The rate of conversion to THA within 1 year was 2.85%. When compared to rates in the general population, the relative risks [RRs] of requiring a THA (age <50 years, RR = 57.66, P < .001; age >50 years, RR = 22.05, P < .001), sustaining a proximal femur fracture (age <50 years, RR = 18.02, P < .001; age >50 years, RR = 2.23, P < .001), or experiencing a hip dislocation (RR 19.60, P < .001) at 1 year after hip arthroscopy were significantly higher in all age groups. CONCLUSIONS: Higher major complication rates after hip arthroscopy were observed using a national payer-based database than previously reported in the literature, especially in regard to hip dislocations and proximal femur fractures. Rates of total hip arthroplasty were similar to prior studies, whereas the rates of revision hip arthroscopy were higher. LEVEL OF EVIDENCE: Level IV, case series.

Total Joint Arthroplasty in Patients with Human Immunodeficiency Virus.

With the advent of highly active antiretroviral therapy (HAART), total joint arthroplasty has become a safe and effective procedure for patients infected with the human immunodeficiency virus (HIV). A correlation between a low CD4+ count (<200 cells/mm3) and major postoperative complications such as deep joint infection has been postulated, although high-level studies are not available in the literature. As most studies have not demonstrated an increase in the incidence of deep-vein thrombosis in patients with HIV/AIDS (acquired immunodeficiency syndrome), our recommendation is to use the standard prophylaxis that is followed by the operating surgeon.

Total joint arthroplasty in patients with chronic infectious liver disease.

The opportunity for total joint arthroplasty (TJA) in patients with chronic infectious liver disease is rapidly expanding. This is the product of both superior survival of chronic hepatitis patients, evolving implant technologies, and improvement of techniques in TJA. Unfortunately, treating this group of patients is not without significant challenges that can stem from both intrahepatic and extrahepatic clinical manifestations. Moreover, many subclinical changes occur in this cohort that can alter hemostasis, wound healing, and infection risk even in the asymptomatic patient. In this review, we discuss the various clinical presentations of chronic infectious liver disease and summarize the relevant literature involving total joint arthroplasty for this population. Hopefully, through appropriate patient selection and perioperative optimization, treating surgeons should see continued improvement in outcomes for patients with chronic infectious liver disease.

Total knee arthroplasty in a patient with hypofibrinogenemia.

Patients with afibrinogenemia or hypofibrinogenemia present a unique challenge to the arthroplasty surgeon as fibrinogen is a key contributor to hemostasis. Patients with these disorders are known to have a higher risk for postsurgical bleeding complications. We present the case of a patient with hypofibrinogenemia who underwent an elective total knee arthroplasty. Our colleagues in hematology-oncology guided us initially to achieve and maintain appropriate fibrinogen levels in the early perioperative period. However, the patient developed an acute joint effusion and subsequent infection 4 weeks after her initial operation. Her fibrinogen levels were noted to have fallen below the target range by that time, and it was also revealed that the patient failed to follow-up with hematology-oncology to monitor her levels. Based on our review of the available literature, we recommend that patient's fibrinogen levels be closely monitored and maintained ideally >100 mg/dL not only in the initial perioperative window but perhaps for the first 4-6 weeks postoperatively as well.

Biochemical and Cellular Assessment of Acetabular Chondral Flaps Identified During Hip Arthroscopy.

PURPOSE: To analyze chondral flaps debrided during hip arthroscopy to determine their biochemical and cellular composition. METHODS: Thirty-one full-thickness acetabular chondral flaps were collected during hip arthroscopy. Biochemical analysis was undertaken in 21 flaps from 20 patients, and cellular viability was determined in 10 flaps from 10 patients. Biochemical analysis included concentrations of (1) DNA (an indicator of chondrocyte content), (2) hydroxyproline (an indicator of collagen content), and (3) glycosaminoglycan (an indicator of chondrocyte biosynthesis). Higher values for these parameters indicated more healthy tissue. The flaps were examined to determine the percentage of viable chondrocytes. RESULTS: The percentage of acetabular chondral flap specimens that had concentrations within 1 SD of the mean values reported in previous normal cartilage studies was 38% for DNA, 0% for glycosaminoglycan, and 43% for hydroxyproline. The average cellular viability of our acetabular chondral flap specimens was 39% (SD, 14%). Only 2 of the 10 specimens had more than half the cells still viable. There was no correlation between (1) the gross examination of the joint or knowledge of the patient's demographic characteristics and symptoms and (2) biochemical properties and cell viability of the flap, with one exception: a degenerative appearance of the surrounding cartilage correlated with a higher hydroxyproline concentration. CONCLUSIONS: Although full-thickness acetabular chondral flaps can appear normal grossly, the biochemical properties and percentage of live chondrocytes in full-thickness chondral flaps encountered in hip arthroscopy show that this tissue is not normal. CLINICAL RELEVANCE: There has been recent interest in repairing chondral flaps encountered during hip arthroscopy. These data suggest that acetabular chondral flaps are not biochemically and cellularly normal. Although these flaps may still be valuable mechanically and/or as a scaffold in some conductive or inductive capacity, further study is required to assess the clinical benefit of repair.

Smoking cessation and bone healing: optimal cessation timing.

Smoking is a worldwide epidemic. Complications related to smoking behavior generate an economic loss around $193 billion annually. In addition to impacting chronic health conditions, smoking is linked to increased perioperative complications in those with current or previous smoking history. Numerous studies have demonstrated more frequent surgical complications including higher rates of infection, poor wound healing, heightened pain complaints, and increased pulmonary morbidities in patients with a smoking history. Longer preoperative cessation periods also seem to correlate with reduced rates. At roughly 4 weeks of cessation prior to surgery, complication rates more closely reflect individuals without a smoking history in comparison with those that smoke within 4 weeks of surgery. In the musculoskeletal system, a similar trend has been observed in smokers with higher rates of fractures, nonunions, malunions, infections, osteomyelitis, and lower functional scores compared to non-smoking patients. Unfortunately, the present literature lacks robust data suggesting a temporal relationship between smoking cessation and bone healing. In our review, we analyze pseudoarthrosis rates following spinal fusion to suggest that bone healing in the context of smoking behavior follows a similar time sequence as observed in wound healing. We also discuss the implications for further clarity on bone healing and smoking cessation within orthopedics including improved risk stratification and better identification of circumstances where adjunct therapy is appropriate.