Stemless anatomic total shoulder arthroplasty is associated with less early postoperative pain.

Background: Improvements in pain control after shoulder arthroplasty with a reduction in narcotic use continues to be an important postoperative goal. With the increased utilization of stemless anatomic total shoulder arthroplasty (aTSA), it is relevant to compare between stemmed and stemless arthroplasty to assess if there is any association between this implant design change and early postoperative pain. Methods: Patients from a multicenter, prospectively-maintained database who had undergone a stemless aTSA with a minimum of two year clinical follow-up were retrospectively identified. Patients who underwent aTSA with a short stem were identified in the same registry, and matched to the stemless aTSA patients by age, sex and preoperative pain score. The primary study outcome was the Visual Analog Scale pain score. Secondary pain outcomes were the American Shoulder and Elbow Surgeons shoulder pain subscore, Western Ontario Osteoarthritis of the Shoulder physical symptoms subscore, and the Single Assessment Numeric Evaluation score. Finally, the percentage of patients who could sleep on the affected shoulder was assessed for each group. These pain-related clinical outcomes were assessed and compared preoperatively, and postoperatively at 9 weeks, 26 weeks, one year and two years. For all statistical comparisons, P > .05 was considered significant. Results: 124 patients were included in the study; 62 in each group. At 9 weeks after surgery, statistically significantly improved pain control was reported by patients undergoing stemless aTSA, as assessed by the Visual Analog Scale (stemless: 1.5, stemmed: 2.5, P = .001), American Shoulder and Elbow Surgeons pain subscore (stemless: 42.4, stemmed: 37.3, P < .001), Western Ontario Osteoarthritis of the Shoulder Physical Symptoms (stemless: 80.3, stemmed: 73.1, P = .006) and Single Assessment Numeric Evaluation (stemless: 58.1, stemmed: 47.4, P = .011). Patients who underwent a stemless aTSA were significantly more likely to be able to sleep on the affected shoulder at 9 weeks (29% vs. 11%, odds ratio 3.2, 95% confidence interval 1.2-8.4, P = .014). By 26 weeks postoperatively, there were no differences in all pain-specific outcomes. At two years postoperatively, patient-reported outcomes, range of motion, and strength measures were all similar between the two cohorts. Conclusion: Stemless aTSA provides earlier improvement in postoperative shoulder pain compared to matched patients undergoing short-stem aTSA. Additionally, earlier return to sleeping on the affected shoulder was reported in the stemless aTSA group. The majority of these differences dissipate by 26 weeks postoperatively and there were no differences in pain, patient-reported outcomes, range of motion or strength measures between stemless and short-stem aTSA at 2 years postoperatively.

Evaluation of the Painful Total Shoulder Arthroplasty.

Despite the overall success of anatomic and reverse total shoulder arthroplasties (aTSA and rTSA), some patients continue to have or develop pain postoperatively. As the number of shoulder arthroplasties continues to increase in the United States, it is important that surgeons are able to recognize, diagnose, and treat the various pathologies. Some painful etiologies are specific to either aTSA or rTSA, and others can occur with both implant types. Infections, stiffness, neurologic syndromes, polyethylene wear, aseptic implant loosening, and metal allergies occur, regardless of implant choice. However, after an aTSA, subscapularis repair failure, superior rotator cuff tear, and joint overstuffing can result in shoulder pain. After a rTSA, specific causes of postoperative pain include instability, scapular notching, acromial or scapular spine fractures, subcoracoid pain, and neurologic injury. Regardless of the diagnosis, the surgeon must be methodical in the evaluation and, when appropriate, use blood work, advanced imaging studies, joint aspirations, shoulder arthroscopy, and nerve studies. Once diagnosed, appropriate treatment should be undertaken to resolve the cause of the pain or at least minimize the effect of the pain on the patient's outcome.

Short-term clinical and radiographic outcomes of a hybrid all-polyethylene glenoid based on preoperative glenoid morphology.

BACKGROUND: The primary purpose of this study was to compare 2-year anatomic total shoulder arthroplasty (TSA) functional and radiographic outcomes between Walch type A and B glenoids treated with an all-polyethylene glenoid designed for hybrid fixation with peripheral cement and central osseous integration. The secondary purpose was to evaluate outcomes based on central peg technique. The hypotheses were that there would be no difference in short-term radiographic or functional outcome scores based on preoperative glenoid morphology or central peg technique. METHODS: We performed a multicenter retrospective review of patients who underwent TSA with the same hybrid all-polyethylene glenoid and had minimum 2-year follow-up. Patient-reported outcomes and radiographic outcomes were analyzed based on preoperative Walch morphology and central peg technique. Radiographic analysis included preoperative glenoid morphology; preoperative and postoperative glenoid version, glenoid inclination, and posterior humeral head subluxation; and postoperative glenoid radiolucencies according to the Wirth and Lazarus classifications. RESULTS: A total of 266 patients with a mean age of 64.9 ± 8.2 years were evaluated at a mean of 28 months postoperatively. Postoperatively, there were significant improvements in all functional outcome measures (P < .001), range-of-motion measures (forward elevation, external rotation at 0°, external rotation at 90°, internal rotation by spinal level, and internal rotation at 90°; P < .001), and strength measures (Constant, external rotation, and modified belly press; P < .001). There were no clinically meaningful differences in functional outcomes or statistically significant differences in radiographic appearance between Walch type A and B glenoids. Subgroup analysis revealed that glenoids with a cemented central peg had the worst radiographic outcomes based on Lazarus scoring. CONCLUSION: Patients undergoing TSA with a hybrid in-line pegged glenoid have excellent clinical outcomes at short-term follow-up regardless of preoperative glenoid morphology. Different central peg techniques do not appear to play a significant role in the risk of glenoid component lucencies at 2 years postoperatively.

Reverse total shoulder arthroplasty for patients with preserved active elevation and moderate-to-severe pain: a matched cohort study.

BACKGROUND: Patients undergoing reverse total shoulder arthroplasty (RTSA) predictably report reduced pain and improved function postoperatively. However, it is not known if patients with differing preoperative active motion achieve the same benefit after surgery. The purpose of the present study is to evaluate patient-reported outcomes (PROs), range of motion (ROM), and satisfaction after RTSA in patients with moderate-to-severe pain with preserved active preoperative ROM compared with matched controls with restricted preoperative active ROM. METHODS: A multicenter shoulder arthroplasty registry was utilized to identify patients with at least two-year clinical follow-up after RTSA with a 135° implant. The study cohort with preserved motion included patients with greater than one standard deviation above the overall mean for preoperative forward elevation (FE) (140°) as well as a preoperative visual analog pain scale (VAS) ≥ 5.0. The control cohort with more restricted motion had preoperative FE of less than 140° and also with preoperative VAS ≥5.0. The control patients were matched 2:1 to study patients by age (±2 years), sex, and preoperative VAS (±1.5). Outcomes measured were as follows: PROs, ROM, strength, and strength and satisfaction. RESULTS: Twenty-seven patients were identified that comprised the preserved preoperative FE study cohort; 54 patients were included in the restricted elevation cohort as controls. The groups were similar at baseline for demographics, surgical diagnoses, and most PROs, other than the Constant-Murley, which was higher in the preserved motion cohort. At two years postoperatively, both cohorts demonstrated similar PROs, strength, and ROM (other than internal rotation with the arm abducted 90 degrees) and had a similar number of patients who rated the RTSA as meeting or exceeding their expectations. The change in ROM from preoperatively was significantly different with the restricted cohort, achieving a larger increase in forward flexion (51 ± 26° vs. -13 ± 35°, P < .001). CONCLUSION: Patients indicated for RTSA with preserved preoperative FE and moderate pain achieve similar final ROM, pain reduction, increases, and strength compared with patients who undergo RTSA with restricted preoperative FE. Despite losing on average 13 degrees of FE from preoperatively by two years postoperatively, patients with preserved preoperative FE are comparably satisfied with their outcome.

Management of bilateral osteochondritis dissecans of the trochlea in a skeletally immature patient.

Osteochondritis dissecans (OCD) lesions are injuries that occur more commonly in the skeletally immature population. In most cases, the aetiology is not well understood, but fortunately, many OCD lesions may heal on their own over time, particularly in skeletally immature patients with open physes. Conversely, if the lesion is considered unstable, surgical intervention may be required. This case demonstrates an especially rare presentation of bilateral OCD lesions within the lateral femoral trochlear facet. The lesions became symptomatic approximately 1 year apart without a specific injury. Non-operative treatment was not recommended in either case due to the size and instability of each lesion. The surgical treatment used an augmented microfracture technique. At 12 and 23 months after surgery, both knees remain asymptomatic and the patient has returned to their desired activities.

Sulcus Deepening Trochleoplasty and Medial Patellofemoral Ligament Reconstruction for Patellofemoral Instability: A 2-Year Study.

PURPOSE: To evaluate outcome data of patients undergoing DeJour sulcus-deepening trochleoplasty with medial patellofemoral ligament reconstruction (MPFLR) for high-grade trochlear dysplasia at a single institution in the United States. METHODS: A total of 67 patients (76 knees) with severe trochlear dysplasia and recurrent patellar instability were prospectively enrolled and underwent DeJour sulcus-deepening trochleoplasty with MPFLR from 2011 to 2019. Inclusion criteria included recurrent lateral patellar instability following failure of conservative treatment with radiographic evidence of severe trochlear dysplasia (DeJour types B or D). Patients with less than 2-year follow-up were excluded. Radiographic analysis, physical examination, clinical follow-up, patient demographics, and patient-reported outcome measures were obtained for all patients at each visit. RESULTS: Forty patients (44 knees) had complete 2-year or longer follow-up and were included. The majority of patients were female (81.8%) with a mean age of 19.2 years (standard deviation [SD] 6.7; range 13.2-47.0). Follow-up ranged from 2.0 years to 6.8 years (mean 3.6 years, SD 1.35). In total, 45.5% had failed previous surgery for patellar instability. Eight knees developed arthrofibrosis and the overall reoperation rate was 27.3%. No patients had fixation failure and no further surgery was required for instability. The mean preoperative International Knee Documentation Committee score of 50.8 improved to 79.1 (P < .001), and the mean preoperative Kujala score of 56.4 improved to 86.5 (P < .001). Patients reported high satisfaction rates (mean 9.1 of 10). When applicable, 100% of patients returned to work, whereas 84.8% returned to sport. There was no significant radiographic progression of patellofemoral arthritis at a mean of 2.4 years after surgery (SD 1.7). CONCLUSIONS: DeJour sulcus-deepening trochleoplasty combined with MPFLR and used with tibial tubercle osteotomy and lateral release is a reliable and effective treatment for recurrent patellar instability due to severe trochlear dysplasia, even in this group with many revisions of previous procedures. LEVEL OF EVIDENCE: IV, case series.

Predictors of Osteochondral Lesions of the Talus in Patients Undergoing Broström-Gould Ankle Ligament Reconstruction.

Chronic ankle instability is associated with intra-articular and extra-articular ankle pathologies, including osteochondral lesions of the talus. Patients with these lesions are at risk for treatment failure for their ankle instability. Identifying these patients is important and helps to guide operative versus nonoperative treatment. There is no literature examining which patient characteristics may be used to predict concomitant osteochondral lesions of the talus. A retrospective chart review was performed on patients (N = 192) who underwent a primary Broström-Gould lateral ankle ligament reconstruction for chronic ankle instability from 2010 to 2014. Preoperative findings, magnetic resonance imaging, and operative procedures were documented. Patients with and without a lesion were divided into 2 cohorts. Fifty-three (27.6%) patients had 1 lesion identified on preoperative magnetic resonance imaging. Forty (69.0%) of these lesions were medial, 18 (31.0%) were lateral, and 5 patients had both. Female sex was a negative predictor of a concomitant lesion (p = .013). Patients were less likely to have concomitant peroneal tendinopathy (30.2% vs 48.9%; p = .019) in the presence of a lesion. However, sports participation was a positive predictor of a concomitant lesion (p = .001). The remainder of the variables (age, body mass index, smoking, trauma, duration, contralateral instability, global laxity) did not show a significant difference. In patients who underwent lateral ankle ligament reconstruction, females were less likely to have a lesion than males. Patients with peroneal tendinopathy were less likely to have a lesion compared with patients without. Additionally, athletic participation was a positive predictor of a concomitant lesion.

Correction to: Shoulder Arthroplasty for Humeral Head Avascular Necrosis Is Associated with Increased Postoperative Complications.

[This corrects the article DOI: 10.1007/s11420-017-9562-8.].

Lateral Patellar Instability in the Skeletally Mature Patient: Evaluation and Surgical Management.

Lateral patellar instability is a common disease process that affects all types of patients. Depending on the patient's anatomy and the results of preoperative imaging, surgical management options include medial patellofemoral ligament reconstruction, tibial tubercle osteotomy, and sulcus-deepening trochleoplasty. Medial patellofemoral ligament reconstruction or repair is useful for almost all patients, whereas tibial tubercle osteotomy is helpful to correct a lateralized tibial tubercle and the associated elevated lateral pull of the extensor mechanism. For a select subset of patients with severe trochlear dysplasia, a sulcus-deepening trochleoplasty can be a useful option to prevent future patellar instability. Many technical considerations exist for each procedure, and in most situations, no consensus exists to direct surgeons on the superior technique.

Shoulder Arthroplasty for Humeral Head Avascular Necrosis Is Associated With Increased Postoperative Complications.

Background: Humeral head avascular necrosis (AVN) of differing etiologies may lead to shoulder arthroplasty due to subchondral bone collapse and deformity of the articular surface. There have been no large studies evaluating the complications for these patients after they undergo total shoulder arthroplasty (TSA). Questions/Purposes: The first objective of this study is to evaluate the complication rate after TSA in patients with humeral head AVN. The secondary objective is to compare the complication rates among the different etiologies of the AVN. Methods: Patients who underwent TSA were identified in the PearlDiver database using ICD-9 codes. Patients who underwent shoulder arthroplasty for humeral head AVN were identified using ICD-9 codes and were subclassified according to AVN etiology (posttraumatic, alcohol use, chronic steroid use, and idiopathic). Complications evaluated included postoperative infection within 6 months, dislocation within 1 year, revision shoulder arthroplasty up to 8 years postoperatively, shoulder stiffness within 1 year, and periprosthetic fracture within 1 year and systemic complications within 3 months. Postoperative complication rates were compared to controls. Results: The study cohorts included 4129 TSA patients with AVN with 141,778 control TSA patients. Patients with posttraumatic AVN were significantly more likely to have a postoperative infection (OR 2.47, P < 0.001), dislocation (OR 1.45, P = 0.029), revision surgery (OR 1.53, P = 0.001), stiffness (OR 1.24, P = 0.042), and systemic complication (OR 1.49, P < 0.001). Steroid-associated AVN was associated with a significantly increased risk for a postoperative infection (OR 1.72, P = 0.004), revision surgery (OR 1.33, P = 0.040), fracture (OR 2.76, P = 0.002), and systemic complication (OR 1.59, P < 0.001). Idiopathic and alcohol-associated AVN were not significantly associated with any of the postoperative evaluated complications. Conclusions: TSA in patients with humeral head AVN is associated with significantly increased rates of numerous postoperative complications compared to patients without a diagnosis of AVN, including infection, dislocation, revision arthroplasty, stiffness, periprosthetic fracture, and medical complications. Specifically, AVN due to steroid use or from a posttraumatic cause appears to be associated with the statistically highest rates of postoperative TSA complications. Given these findings, orthopedic surgeons should be increasingly aware of this association, which should influence the shared decision-making process of undergoing TSA in patients with humeral head AVN.

Common Injuries in Professional Football Quarterbacks.

PURPOSE OF REVIEW: Professional football quarterbacks are at particular risk for upper extremity injuries due to the physical demands of their position coupled with the inherent risks associated with professional football. This review sought to evaluate current clinical literature to better characterize the injury profile unique to this athletic population. RECENT FINDINGS: Shoulder injuries are the most prevented upper extremity injury among professional football quarterbacks. The quarterback position is disproportionately impacted by shoulder injuries when compared to professional athletes at other positions. Moreover, contrary to other professional throwing athletes, the majority of upper extremity injuries in the professional quarterback result from direct contact as opposed to the throwing motion. The injury profile among professional quarterbacks is unique compared to other positions and other overhead professional throwing athletes. Overall, a paucity of high quality clinical evidence exists to support the management of injuries in this elite population.

Porous Titanium Wedges in Lateral Column Lengthening for Adult-Acquired Flatfoot Deformity.

Lateral column lengthening (LCL) is a common procedure for reconstruction of stage II flexible adult-acquired flatfoot deformity (AAFD). The recent development of porous titanium wedges for this procedure provides an alternative to allograft and autograft. The purpose of this study was to report radiographic and clinical outcomes achieved with porous titanium wedges in LCL. A retrospective analysis of 34 feet in 30 patients with AAFD that received porous titanium wedges for LCL from January 2011 to October 2014. Deformity correction was assessed using both radiographic and clinical parameters. Radiographic correction was assessed using the lateral talo-first metatarsal angle, the talonavicular uncoverage percentage, and the first metatarsocuneiform height. The hindfoot valgus angle was measured. Patients were followed from a minimum of 6 months up to 4 years (mean 16.1 months). Postoperative radiographs demonstrated significant correction in all 3 radiographic criteria and the hindfoot valgus angle. We had no cases of nonunion, no wedge migration, and no wedges have been removed to date. The most common complication was calcaneocuboid joint pain (14.7%). Porous titanium wedges in LCL can achieve good radiographic and clinical correction of AAFD with a low rate of nonunion and other complications. LEVELS OF EVIDENCE: Level IV: Case series.

Epidemiology and Impact on Performance of Lower Extremity Stress Injuries in Professional Basketball Players.

BACKGROUND: Professional basketball players in the National Basketball Association (NBA) subject their lower extremities to significant repetitive loading during both regular-season and off-season training. Little is known about the incidence of lower extremity bony stress injuries and their impact on return to play and performance in these athletes. HYPOTHESIS: Stress injuries of the lower extremity will have significant impact on performance. STUDY DESIGN: Case series. LEVEL OF EVIDENCE: Level 4. METHODS: All bony stress injuries from 2005 to 2015 were identified from the NBA. Number of games missed due to injury and performance statistics were collected from 2 years prior to injury to 2 years after the injury. A linear regression analysis was performed to determine the impact of injury for players who returned to sport. RESULTS: A total of 76 lower extremity bony stress injuries involving 75 NBA players (mean age, 25.4 ± 4.1 years) were identified. Fifty-five percent (42/76) involved the foot, and most injuries occurred during the regular season (82.9%, 63/76), with half occurring within the first 6 weeks. Among players who sustained a fifth metatarsal stress fracture, 42.9% were unable to return to professional play. Players who sustained stress injuries had reduced play performance, specifically related to number of games played ( P = 0.014) and number of steals per game ( P = 0.004). Players who had surgery had significantly better performance at 2 years than those who were managed nonoperatively, independent of the type of injury (ß = 4.561; 95% CI, 1.255-7.868). CONCLUSION: Lower extremity bony stress injuries may significantly affect both short- and long-term player performance and career length. Stress injuries result in decreased player performance, and surgical intervention results in improved performance metrics compared with those treated using conservative methods. CLINICAL RELEVANCE: Stress injuries result in decreased player performance, and surgical intervention results in improved performance metrics.

Patient Perceptions and Current Trends in Internet Use by Orthopedic Outpatients.

BACKGROUND: Many studies have highlighted concerns about the completeness and quality of information found online and how this may affect patients' education about their medical problems. One aspect of internet usage that has received less attention in the literature, however, is patient perception of the information that is gathered online, and how patients use it related to their musculoskeletal care. QUESTIONS/PURPOSES: The objective of the study is to utilize a cross-sectional study design to describe internet usage and patient perceptions of orthopedic online information and to identify differences in usage patterns. METHODS: One thousand two hundred ninety-six questionnaires were distributed to consecutive patients at orthopedic outpatient clinics which consisted of questions pertaining to patients' internet use. Basic demographic data were collected, and subgroup analyses were performed to examine the effect of three variables (age, gender, and clinic type) on various outcomes. RESULTS: 84.9% of patients reported access to the internet. Of patients with internet access, 64.7% reported using the internet for obtaining orthopedic information. 43.1% of the respondents who searched for orthopedic information rated it as "very useful," 56.3% found it "somewhat useful," and 0.6% found it "not at all useful". Younger patients were more likely to have used the internet for health and orthopedic information and to have found this information either very or somewhat useful. Males were more likely to have found the internet information very useful. Overall, only 33.7% of patients who researched their current orthopedic complaint accessed the institutional website for information. CONCLUSION: A large proportion of patients use the internet to research orthopedic information and most patients, especially younger males, find the information useful.

ACL Roof Impingement Revisited: Does the Independent Femoral Drilling Technique Avoid Roof Impingement With Anteriorly Placed Tibial Tunnels?

BACKGROUND: Anatomic femoral tunnel placement for single-bundle anterior cruciate ligament (ACL) reconstruction is now well accepted. The ideal location for the tibial tunnel has not been studied extensively, although some biomechanical and clinical studies suggest that placement of the tibial tunnel in the anterior part of the ACL tibial attachment site may be desirable. However, the concern for intercondylar roof impingement has tempered enthusiasm for anterior tibial tunnel placement. PURPOSE: To compare the potential for intercondylar roof impingement of ACL grafts with anteriorly positioned tibial tunnels after either transtibial (TT) or independent femoral (IF) tunnel drilling. STUDY DESIGN: Controlled laboratory study. METHODS: Twelve fresh-frozen cadaver knees were randomized to either a TT or IF drilling technique. Tibial guide pins were drilled in the anterior third of the native ACL tibial attachment site after debridement. All efforts were made to drill the femoral tunnel anatomically in the center of the attachment site, and the surrogate ACL graft was visualized using 3-dimensional computed tomography. Reformatting was used to evaluate for roof impingement. Tunnel dimensions, knee flexion angles, and intra-articular sagittal graft angles were also measured. The Impingement Review Index (IRI) was used to evaluate for graft impingement. RESULTS: Two grafts (2/6, 33.3%) in the TT group impinged upon the intercondylar roof and demonstrated angular deformity (IRI type 1). No grafts in the IF group impinged, although 2 of 6 (66.7%) IF grafts touched the roof without deformation (IRI type 2). The presence or absence of impingement was not statistically significant. The mean sagittal tibial tunnel guide pin position prior to drilling was 27.6% of the sagittal diameter of the tibia (range, 22%-33.9%). However, computed tomography performed postdrilling detected substantial posterior enlargement in 2 TT specimens. A significant difference in the sagittal graft angle was noted between the 2 groups. TT grafts were more vertical, leading to angular convergence with the roof, whereas IF grafts were more horizontal and universally diverged from the roof. CONCLUSION: The IF technique had no specimens with roof impingement despite an anterior tibial tunnel position, likely due to a more horizontal graft trajectory and anatomic placement of the ACL femoral tunnel. Roof impingement remains a concern after TT ACL reconstruction in the setting of anterior tibial tunnel placement, although statistical significance was not found. Future clinical studies are planned to develop better recommendations for ACL tibial tunnel placement. CLINICAL RELEVANCE: Graft impingement due to excessively anterior tibial tunnel placement using a TT drilling technique has been previously demonstrated; however, this may not be a concern when using an IF tunnel drilling technique. There may also be biomechanical advantages to a more anterior tibial tunnel in IF tunnel ACL reconstruction.

Correct Positioning of the Medial Patellofemoral Ligament: Troubleshooting in the Operating Room.

Medial patellofemoral ligament (MPFL) reconstruction is often required after failed nonoperative management of lateral patellar instability. It is important to properly re-create the native ligament to avoid altering patellofemoral biomechanics. Such alterations can cause knee stiffness, anterior knee pain, and patellofemoral chondrosis. Incorrect femoral location is the most common mistake that affects MPFL graft biomechanics. Authors have described multiple radiographic and anatomical landmarks that assist in determining the appropriate location, and time should be taken to accurately localize this position. Regardless of the reconstruction technique used, the knee should be taken through its full range of motion, before the MPFL graft is secured, to test the biomechanics and reduce the risk of postoperative complications. If the graft becomes too tight as the knee moves into flexion, the femoral location is too proximal and should be adjusted ("high and tight"). By contrast, if the graft becomes too loose in flexion, then the femoral location is too distal ("low and loose"). These simple rules can be used to intraoperatively troubleshoot the tunnel placement.

The Transseptal Arthroscopic Knee Portal Is in Close Proximity to the Popliteal Artery: A Cadaveric Study.

The purpose of this study was to use fluoroscopy to measure the distance between the transseptal portal and the popliteal artery under arthroscopic conditions with an intact posterior knee capsule, and to determine the difference between 90 degrees of knee flexion and full extension. The popliteal artery of eight fresh-frozen cadaveric knees was dissected and cannulated proximal to the knee joint. The posterolateral, posteromedial, and transseptal portals were then established at 90 degrees of flexion. A 4-mm switching stick was placed through the transseptal portal, and barium contrast was injected into the popliteal artery. A lateral fluoroscopic image was taken with the knee in 90 degrees of flexion and full extension, and the distance between the popliteal artery and the switching stick was measured and compared using a paired t-test. In knee flexion, the average distance between the transseptal portal and the anterior aspect of the popliteal artery for the eight cadaveric specimens was 12.0 mm ± 3.3 mm; in extension, this decreased to 9.0 mm ± 2.7 mm. The distance between the transseptal portal and popliteal artery was significantly higher at 90 degrees of knee flexion as compared with extension (p = 0.0005). The transseptal posterior knee arthroscopic portal must be carefully created due to the close proximity to the popliteal artery, and may be closer to the artery than previously reported in specimens with an intact posterior knee capsule. Creating the portal with the knee in flexion significantly displaces the popliteal artery away from the portal reducing the risk of arterial injury.

High altitude is an independent risk factor for venous thromboembolism following arthroscopic rotator cuff repair: a matched case-control study in Medicare patients.

BACKGROUND: Although the risk of venous thromboembolism (VTE) following elective shoulder arthroscopy is low, the large volume of procedures performed each year yields a significant annual burden of patients with thromboembolic complications. The purpose of this study was to evaluate the association of high procedural altitude with the incidence of postoperative VTE following arthroscopic rotator cuff repair. METHODS: A Medicare database was queried for all patients undergoing arthroscopic rotator cuff repair from 2005 to 2012. All patients with procedures performed at an altitude of 4000 feet or higher were grouped into the "high-altitude" study cohort. Patients with procedures performed at an altitude of 100 feet or lower were then matched to patients in the high-altitude cohort on the basis of age, gender, and medical comorbidities. The rate of VTE was then assessed for both the high-altitude and matched low-altitude cohorts within 90 days postoperatively. RESULTS: The rates of combined VTE (odds ratio [OR], 2.6; P < .0001), pulmonary embolism (OR, 4.3; P < .0001), and lower extremity deep venous thrombosis within 90 days (OR, 2.2; P = .029) were all significantly higher in patients with procedures performed at high altitude compared with matched patients with the same procedures performed at low altitude. CONCLUSIONS: Procedural altitude >4000 feet is associated with significantly increased rates of postoperative VTE, including deep venous thrombosis and pulmonary embolism, compared with age-, gender-, and comorbidity-matched patients undergoing the same procedures at altitudes <100 feet.

MPFL graft fixation in low degrees of knee flexion minimizes errors made in the femoral location.

PURPOSE: To evaluate the appropriate amount of knee flexion in which to secure the graft during medial patellofemoral ligament (MPFL) reconstruction. METHODS: Heavy suture was used to simulate graft tissue during MPFL reconstruction on eight fresh-frozen cadaveric knees. The sutures were passed through two transverse patellar tunnels and draped over a Kirschner wire at Schöttle's point on the femur. Suture displacement at the location of the wire was measured during knee range of motion from 0 to 135°. The wire's location was then moved to 3 additional locations (1 cm proximal, 1 cm distal, and 1 cm anterior), and the measurements were repeated. RESULTS: Using Schöttle's point, the suture length did not vary throughout all ranges of knee flexion. The distal location resulted in a greater distance between attachment points (i.e. graft tightened) if the measurements began with the knee flexed and then brought into extension. Conversely, with the proximal location, the opposite occurred as the knee was extended (i.e. graft loosened). For all locations other than Schöttle's point, the amount of initial knee flexion for fixation was directly related to the amount of suture length change when the knee was brought into extension. CONCLUSION: For non-anatomic femoral MPFL graft fixation locations, suture length (and thus graft length) in full extension becomes increasingly altered if the graft is secured in high degrees of knee flexion. Thus, graft fixation in lower degrees of knee flexion is recommended to minimize over or under tensioning the graft when the knee goes into extension if the graft position is placed in a non-anatomic location. To avoid this problem, fluoroscopy should be used to locate the anatomic footprint of the MPFL insertion. While recognizing the limitations of cadaveric research, this study is the first to provide any data to corroborate the widely used practice of securing the MPFL in lower degrees of knee flexion.