The Role of the Hip Capsule in Restoring Stability in the Initial Phase of Hip Distraction: An In Vivo Analysis.

Background: The labral suction seal has been shown to provide the majority of resistance in the initial phase of hip distraction. However, the effect of an unrepaired interportal capsulotomy and capsular repair on the initial phase of hip distractive stability in vivo is not well understood. Purpose: To investigate the effect of capsular repair on the initial phase of distractive stability of hip joints in patients with femoroacetabular impingement (FAI) syndrome. Study Design: Controlled laboratory study. Methods: Patients undergoing primary hip arthroscopy for FAI between March and August 2020 were prospectively enrolled. Total joint space was measured on fluoroscopic images at the medial and lateral edges of the sourcil at 12.5-lb (5.7-kg) axial traction intervals (up to 100 lb [45.4 kg]) in 3 capsular states: (1) native capsule, (2) interportal capsulotomy, and (3) capsular repair. Distraction on anteroposterior radiographs was calculated as the difference between total joint space at each traction interval and baseline joint space at 0 lb, normalized to millimeters. The native, capsulotomy, and capsular repair states were compared using Wilcoxon signed-rank and McNemar tests. Results: Included were 36 hips in 35 patients. The median force required to distract ≥3 mm was 75 lb (34.0 kg; 95% CI, 70-80 lb [31.8-36.3 kg]) in both the native and capsular repair states (P = .629), which was significantly greater than the median force required to distract ≥3 mm in the capsulotomy state (50 lb [22.7 kg]; 95% CI, 45-55 lb [20.4-24.9 kg]) (P < .001). The most rapid rates of change in joint space were observed at the traction interval at which hips first achieved ≥3 mm of distraction (n = 33 hips; 92%). Conclusion: The traction force at which hips distracted ≥3 mm was 75 lb (34.0 kg) in both the native capsular and capsular repair states. Significantly less traction force (50 lb [22.7 kg]) distracted hips ≥3 mm in the capsulotomy state. Complete capsular closure after interportal capsulotomy resulted in restoration of initial distractive stability relative to the unrepaired capsulotomy state at time zero after primary hip arthroscopy. Clinical Relevance: This study provides surgeons with an improved understanding of the additional stability to the hip joint from capsular repair after hip arthroscopy for FAI syndrome.

Meniscus Tear Requiring Intraoperative Repair Does Not Influence Midterm Patient-Reported Outcomes in Operatively Treated Tibial Plateau Fractures.

OBJECTIVES: Evaluate whether intraoperatively repaired lateral meniscus injuries impact midterm patient-reported outcomes in those undergoing operative fixation of tibial plateau fracture. DESIGN: Retrospective cohort study. SETTING: Level I trauma center. PATIENT SELECTION CRITERIA: All patients (n = 207) who underwent operative fixation of a tibial plateau fracture from 2016 to 2021 with a minimum of 10-month follow-up. OUTCOME MEASURES AND COMPARISONS: The Patient-Reported Outcomes Measurement Information System Physical Function, Knee Injury and Osteoarthritis Outcome Score, and the PROMIS-Preference health utility score. RESULTS: Overall, 207 patients were included with average follow-up of 2.9 years. Seventy-three patients (35%) underwent intraoperative lateral meniscus repair. Gender, age, body mass index, Charlson comorbidity index, days to surgery, ligamentous knee injury, open fracture, vascular injury, polytraumatic injuries, Schatzker classification, and Orthopaedic Trauma Association classification were not associated with meniscal repair ( P > 0.05). Rates of reoperation (42% vs. 31%, P = 0.11), infection (8% vs. 10%, P = 0.60), return to work (78% vs. 75%, P = 0.73), and subsequent total knee arthroplasty (8% vs. 5%, P = 0.39) were also similar between those who had a meniscal repair and those without a meniscal injury, respectively. There was no difference in Patient-Reported Outcomes Measurement Information System Physical Function (46.3 vs. 45.8, P = 0.707), PROMIS-Preference (0.51 vs. 0.50, P = 0.729), and all Knee Injury and Osteoarthritis Outcome Score domain scores at the final follow-up between those who had a meniscal repair and those without a meniscal injury, respectively. CONCLUSIONS: In patients with an operatively treated tibial plateau fracture, the presence of a concomitant intraoperatively identified and repaired lateral meniscal tear results in similar midterm PROMs and complication rates when compared with patients without meniscal injury. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Analysis of acute extremity compartment syndrome using a genealogic population database.

INTRODUCTION: Acute extremity compartment syndrome ("CS") is an under-researched, highly morbid condition affecting trauma populations. The purpose of this study was to analyze incidence rates and risk factors for extremity compartment syndrome using a high-quality population database. Additionally, we evaluated heritable risk for CS using available genealogic data. We hypothesized that diagnosis of extremity compartment syndrome would demonstrate heritability. MATERIALS AND METHODS: Adult patients with fractures of the tibia, femur, and upper extremity were retrospectively identified by ICD-9, ICD-10, and CPT codes from 1996 to 2020 in a statewide hospital database. Exposed and unexposed cohorts were created based on a diagnosis of CS. Available demographic data were analyzed to determine risk factors for compartment syndrome using logistic regression. Mortality risk at the final follow-up was evaluated using Cox proportional hazard modeling. Patients with a diagnosis of CS were matched with those without a diagnosis for heritability analysis. RESULTS: Of 158,624 fractures, 931 patients were diagnosed with CS. Incidence of CS was 0.59% (tibia 0.83%, femur 0.31%, upper extremity 0.27%). Male sex (78.1% vs. 46.4%; p < 0.001; RR = 3.24), younger age at fracture (38.8 vs. 48.0 years; p < 0.001; RR = 0.74), Medicaid enrollment (13.2% vs. 9.3%; p < 0.001; RR = 1.58), and smoking (41.1% vs. 31.1%; p < 0.001; RR 1.67) were significant risk factors for CS. CS was associated with mortality (RR 1.61, p < 0.001) at mean follow-up 8.9 years in the CS cohort. No significant heritable risk was found for diagnosis of CS. CONCLUSIONS: Without isolating high-risk fractures, rates of CS are lower than previously reported in the literature. Male sex, younger age, smoking, and Medicaid enrollment were independent risk factors for CS. CS increased mortality risk at long-term follow-up. No heritable risk was found for CS. LEVEL OF EVIDENCE: III.

Establishing the Patient Acceptable Symptom State Thresholds for Patient-Reported Outcomes after Operatively Treated Tibial Plateau Fractures.

OBJECTIVES: Define patient-acceptable symptom state (PASS) thresholds and factors affecting PASS thresholds for Patient-Reported Outcomes Measurement Information System (PROMIS) Physical Function (PF) and Knee Injury and Osteoarthritis Outcome Score (KOOS) following operatively treated tibial plateau fractures. DESIGN: Retrospective cohort. SETTING: Single Level I academic trauma center. PATIENT SELECTION CRITERIA: All patients (n = 159) who underwent fixation of a tibial plateau fracture from 2016 to 2021 and completed patient-reported outcome measures (PROMs) at minimum 1-year follow-up were enrolled for the study. OUTCOME MEASURES AND COMPARISONS: PASS thresholds for global outcome (PASS-Global), pain (PASS-Pain), and function (PASS-Function) were determined using anchor-based questions such as "How satisfied are you today with your injured lower extremity?" with answer choices of very satisfied, satisfied, neutral, unsatisfied, and very unsatisfied. PASS thresholds for each PROM were calculated using 3 methods: (1) 80% specificity, (2) 75th percentile, and (3) Youden Index. RESULTS: Sixty percent of patients were satisfied with their global outcome and 53% with function. Using 80% specificity, 75th percentile, and Youden Index, PASS-Global thresholds were 48.5, 44.5, and 47.9 for PROMIS-PF and 56.3, 56.2, and 56.3 for KOOS-QOL, respectively. PASS-Pain threshold for KOOS-Pain was 84.4, 80.6, and 80.6, respectively. PASS-Function thresholds were 48.9, 46.8, and 48 for PROMIS-PF and 94.1, 90.2, and 86.8 for KOOS-ADL, respectively. Younger patients and those with bicondylar fractures or infections were associated with significantly lower PASS-Pain thresholds. Schatzker II fractures, lateral column involvement, or isolated lateral approach resulted in significantly higher PASS-Global and PASS-Function thresholds. CONCLUSIONS: This study defines global, functional, and pain PASS thresholds for tibial plateau fractures. Patients with bicondylar fractures, infections, and medial column involvement were more often unsatisfied. These thresholds are valuable references to identify patients who have attained satisfactory outcomes and to counsel patients with risk factors for unsatisfactory outcomes following tibial plateau fractures. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Worse Quality of Life Associated With Hyperextension Varus Tibial Plateau Fracture Pattern.

OBJECTIVES: Compare patient-reported outcome measures between hyperextension varus tibial plateau (HEVTP) fracture patterns to non-HEVTP fracture patterns. DESIGN: Retrospective study. SETTING: Single academic Level 1 Trauma Center. PATIENT SELECTION CRITERIA: All patients who underwent fixation of a tibial plateau fracture from 2016 to 2021 were collected. Exclusion criteria included inaccurate Current Procedural Terminology code, ipsilateral compartment syndrome, bilateral fractures, incomplete medical records, or follow-up <10 months. OUTCOME MEASURES AND COMPARISONS: In patients who underwent fixation of a tibial plateau fracture, compare Patient-Reported Outcomes Measurement Information System-Physical Function, PROMIS Preference, and Knee Injury and Osteoarthritis Outcome Score (KOOS) between patients with a HEVTP pattern with those without. RESULTS: Two-hundred and seven patients were included, of which 17 (8%) had HEVTP fractures. Compared with non-HEVTP fracture patterns, patients with HEVTP injuries were younger (42.6 vs. 51.0, P = 0.025), more commonly male (71% vs. 44%, P = 0.033), and had higher body mass index (32.8 vs. 28.0, P = 0.05). HEVTP fractures had significantly more ligamentous knee (29% vs. 6%, P = 0.007) and vascular (12% vs. 1%, P = 0.035) injuries. Patient-Reported Outcomes Measurement Information System-Physical Function scores were similar between groups; however, PROMIS-Preference (0.37 vs. 0.51, P = 0.017) was significantly lower in HEVTP fractures. KOOS pain, activities of daily living, and quality-of-life scores were statistically lower in HEVTP fractures, but only KOOS quality-of-life was clinically relevant (41.7 vs. 59.3, P = 0.004). CONCLUSIONS: The HEVTP fracture pattern, whether unicondylar or bicondylar, was associated with a higher rate of ligamentous and vascular injuries compared with non-HEVTP fracture patterns. They were also associated with worse health-related quality of life at midterm follow-up. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Return to Skiing After Tibial Plateau Fracture.

Background: Tibial plateau fractures in skiers are devastating injuries with increasing incidence. Few studies have evaluated patient-reported outcomes and return to skiing after operative fixation of a tibial plateau fracture. Purpose: To (1) identify demographic factors, fracture characteristics, and patient-reported outcome measures that are associated with return to skiing and (2) characterize changes in skiing performance after operative fixation of a tibial plateau fracture. Study Design: Case series; Level of evidence, 4. Methods: We reviewed all operative tibial plateau fractures performed between 2016 and 2021 at a single level-1 trauma center. Patients with a minimum of 10-month follow-up data were included. Patients who self-identified as skiers or were injured skiing were divided into those who returned to skiing and those who did not postoperatively. Patients were contacted to complete the Patient-Reported Outcomes Measurement Information System-Physical Function domain (PROMIS-PF), the Knee injury and Osteoarthritis Outcome Score-Activities of Living (KOOS-ADL), and a custom return-to-skiing questionnaire. Multivariate logistic regression was performed with sex, injury while skiing, PROMIS-PF, and KOOS-ADL as covariates to evaluate factors predictive of return to skiing. Results: A total of 90 skiers with a mean follow-up of 3.4 ± 1.5 years were included in the analysis. The rate of return to skiing was 45.6% (n = 41). The return cohort was significantly more likely to be men (66% vs 41%; P = .018) and injured while skiing (63% vs 39%; P = .020). In the return cohort, 51.2% returned to skiing 12 months postoperatively. The percentage of patients who self-reported skiing on expert terrain dropped by half from pre- to postinjury (61% vs 29.3%, respectively). Only 78% of return skiers had regained comfort with skiing at the final follow-up. Most patients (65%) felt the hardest aspect of returning to skiing was psychological. In the multivariate regression, the male sex and KOOS-ADL independently predicted return to skiing (P = .006 and P = .028, respectively). Conclusion: Fewer than half of skiers who underwent operative fixation of a tibial plateau fracture could return to skiing at a mean 3-year follow-up. The knee-specific KOOS-ADL outperformed the global PROMIS-PF in predicting a return to skiing.

Familial Analysis of Nonunion in a Genealogic Population Database Demonstrates No Evidence of Heritable Risk.

OBJECTIVE: To determine whether there is evidence of heritable risk for nonunion using a large, state-wide population database. DESIGN: Database. SETTING: Level 1 Trauma Center. POPULATION: All Utah residents from 1996 to 2021 who sustained a long bone fracture and their family members were included. OUTCOMES: The primary outcome was nonunion and the prevalence of nonunion among the patients' first-, second-, and third-degree relatives. The secondary objective was to identify demographic, injury, and socioeconomic risk factors associated with nonunion. RESULTS: In total, 150,263 fractures and 6577 nonunions (4.4%) were identified. This was highly refined to a 1:3 matched cohort of 4667 nonunions of 13,981 fractures for familial clustering analysis. Cox proportional hazards did not demonstrate excessive risk of nonunion among first- ( P = 0.863), second- ( P = 0.509), and third-degree relatives ( P = 0.252). Further analysis of the entire cohort demonstrated that male sex (relative risk [RR] = 1.15; P < 0.001), Medicaid enrollment (RR = 2.64; P < 0.001), open fracture (RR = 2.53; P < 0.001), age group 41-60 years (RR = 1.43; P < 0.001), and a history of obesity (RR = 1.20; P < 0.001) were independent risk factors for nonunion. CONCLUSIONS: Our results demonstrate no evidence of heritable risk for nonunion. Independent risk factors for nonunion were male sex, Medicaid enrollment, open fracture, middle age, and a history of obesity. Although it is important to identify modifiable and nonmodifiable risk factors, these results continue to support that the risk of nonunion is multifactorial, relating to injury characteristics, operative techniques, and patient-specific risk factors. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Tibial Plateau Fractures Complicated by Compartment Syndrome Are Associated With a 3 Times Higher Cost of Care.

OBJECTIVES: To determine the impact of acute compartment syndrome (ACS) and identify cost drivers of 1-year total treatment costs for operative tibial plateau fractures. DESIGN: Retrospective review. SETTING: Level 1 trauma center. PATIENTS: 337 patients with tibial plateau fractures, 24 of which were complicated by ACS. OUTCOMES: The primary outcome was total treatment cost over the first year for operatively treated tibial plateau fractures. The secondary objective was to use regression analysis to identify significant cost drivers. RESULTS: The diagnosis of ACS was associated with 2.85 times higher total treatment cost ( P < 0.001). ACS demonstrated increased total treatment cost when controlling for polytrauma ( P < 0.001) and postoperative infection ( P < 0.001). Regression analysis identified 5 variables significantly associated with total cost of care: body mass index, injury severity score, ACS, staged external fixation, and locking fixation ( P < 0.001; R 2 = 0.57). The diagnosis of ACS had the largest impact on total cost with a 3.5× greater impact on cost compared with the next highest variable, staged external fixation. CONCLUSIONS: Tibial plateau fractures complicated by ACS are associated with 2.85 times higher treatment costs over a 1-year period. There were 5 significant variables identified by regression analysis with ACS having the highest impact on total treatment. Together, these 5 factors account for 57% of treatment cost variability. LEVEL OF EVIDENCE: Economic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Hip Joint Venting Decreases the Traction Force Required to Access the Central Compartment During Hip Arthroscopy.

Purpose: To investigate the effect of hip joint venting on the magnitude of traction force required to arthroscopically access the central compartment of the hip. Methods: Patients who underwent hip arthroscopy for femoroacetabular impingement syndrome prospectively underwent an intraoperative traction protocol. Joint space was measured on fluoroscopic images obtained at 50 and 100 lbs of axial traction in the prevented and vented state, and joint space values were normalized to millimetric values using preoperative anteroposterior pelvis radiographs. Venting was performed by inserting a large gauge spinal needle into the hip joint through the hip capsule and removing the stylet. Joint space differences were compared with paired t-tests, Wilcoxon signed-rank tests, and McNemar tests. Results: Fifty hips in 46 patients were included. Mean joint space before venting was 7.4 ± 2.6 mm and 13.3 ± 2.8 mm at 50 and 100 lbs of traction, respectively. Mean joint space after venting was 13.9 ± 2.3 mm and 15.5 ± 2.4 mm at 50 and 100 lbs of traction, respectively. Mean differences in joint space at 50 and 100 lbs were 6.5 mm (P < .001) and 2.2 mm (P < .001), respectively. Mean joint space at 50 lbs in the vented state was significantly greater than in the pre-vented state at 100 lbs (13.9 mm vs. 13.3 mm; P = .002). The increase in joint space between 50 and 100 lbs of traction was significantly greater in the prevented state than in the vented state (5.9 mm vs 1.6 mm; P = .021). Conclusions: Venting the hip reduces the traction force necessary to arthroscopically visualize and instrument the central compartment of the hip by at least 50%. Further, residual negative pressurization of the hip joint remains after breaking the labral suction seal and venting effectively eliminates this phenomenon to aid in hip joint distraction at lower traction force. Level of Evidence: Level IV, case series.

No Increased Risk of Nonunion with Bisphosphonate Use in a Medicare Claims Cohort Following Operatively Treated Long-Bone Fractures.

BACKGROUND: The diagnosis of a fragility fracture represents an important intervention event for the initiation of medical osteoporosis treatments. However, it is unclear if osteoporosis medications increase the risk of nonunion if administered in the setting of acute fracture. The purpose of the present study was to investigate whether bisphosphonates or selective estrogen receptor modulators/hormone replacement therapy (SERM/HRT) are associated with nonunion following fracture in a Medicare population. METHODS: A retrospective analysis of Medicare claims from 2016 to 2019 was performed to identify patients ≥65 years of age who had a surgically treated long-bone fracture as identified with Current Procedural Terminology (CPT) codes and International Classification of Diseases, 10th Revision (ICD-10) codes. Successive claims were linked for each beneficiary through 1 year following the fracture to determine fracture union status. Multivariable logistic regression models were specified to identify the association between medications and fracture union status while controlling for age, sex, race, Charlson Comorbidity Index (CCI), and fracture type. RESULTS: Of the 111,343 included fractures, 10,452 (9.4%) were associated with a diagnosis of nonunion within 1 year. The nonunion group was younger (79.8 ± 8.3 versus 80.6 ± 8.4 years; p < 0.001), more likely to be White (92.4% versus 90.9%; p < 0.001), and more likely to have a CCI of ≥2 (50.9% versus 49.4%; p < 0.001). Bisphosphonate use was more common in the nonunion group (12.2% versus 11.4%; p = 0.017). When controlling for race, age, sex, and CCI, neither bisphosphonates (OR, 1.06 [95% CI, 0.99 to 1.12]; p = 0.101) nor SERM/HRT (OR, 1.13 [0.93 to 1.36]; p = 0.218) were associated with nonunion. Bisphosphonate use within 90 days post-fracture was not significantly associated with nonunion (OR, 0.94 [95% CI, 0.86 to 1.03]; p = 0.175), and the timing of medication administration did not influence fracture union status. CONCLUSIONS: The rate of nonunion after operatively treated long-bone fractures was 9.4%. In this cohort, use of a bisphosphonate or SERM/HRT was not associated with fracture union status at 1 year. Orthopaedic surgeons should not withhold or delay initiating medical therapies for osteoporosis in the setting of acute fracture out of concern for nonunion. LEVEL OF EVIDENCE: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Medial and lateral dual plating of native distal femur fractures: a systematic literature review.

Introduction: Lateral locked plating (LLP) development has improved outcomes for distal femur fractures. However, there is still a modest rate of nonunion in fractures treated with LLP alone, with higher nonunion risk in high-energy fractures, intra-articular involvement, poor bone quality, severe comminution, or bone loss. Several recent studies have demonstrated both the safety and the biomechanical advantage of dual medial and lateral plating (DP). The purpose of this study was to evaluate the clinical outcomes of DP for native distal femoral fractures by performing a systematic review of the literature. Methods: Studies reporting clinical outcomes for DP of native distal femur fractures were identified and systematically reviewed. Publications without full-text manuscripts, those solely involving periprosthetic fractures, or fractures other than distal femur fractures were excluded. Fracture type, mean follow-up, open versus closed fracture, number of bone grafting procedures, nonunion, reoperation rates, and complication data were collected. Methodologic study quality was assessed using the Coleman methodology score. Results: The initial electronic review and reverse inclusion protocol identified 1484 publications. After removal of duplicates and abstract review to exclude studies that did not discuss clinical treatment of femur fractures with dual plating, 101 potential manuscripts were identified and manually reviewed. After final review, 12 studies were included in this study. There were 199 fractures with average follow-up time of 13.72 months. Unplanned reoperations and nonunion occurred in 19 (8.5%) and 9 (4.5%) cases, respectively. The most frequently reported complications were superficial infection (n = 6, 3%) and deep infection (n = 5, 2.5%) postoperatively. Other complications included delayed union (n = 6, 3%) not requiring additional surgical treatment and knee stiffness in four patients (2%) necessitating manipulation under anesthesia or lysis of adhesions. The average Coleman score was 50.5 (range 13.5-72), suggesting that included studies were of moderate-to-poor quality. Conclusions: Clinical research interest in DP of distal femoral fractures has markedly increased in the past few decades. The current data suggest that DP of native distal femoral fractures is associated with favorable nonunion and reoperation rates compared with previously published rates associated with LLP alone. In the current review, DP of distal femoral fractures was associated with acceptable rates of complications and generally good functional outcomes. More high-quality, directly comparable research is necessary to validate the conclusions of this review.

Postless Hip Distraction Systems Decrease the Amount of Traction Force Needed to Obtain Adequate Hip Distraction Versus a Conventional Post Hip Distractor.

PURPOSE: To directly compare hip distraction distance and traction force data for hip arthroscopy performed using a post-basedsystem versus a postless system. METHODS: Adult patients undergoing primary hip arthroscopy for femoroacetabular impingement were prospectively enrolled. Before March 26, 2019, arthroscopy was performed using a post-based system. After this date, the senior author converted to using a postless system. Intraoperative traction force and fluoroscopic distraction distance were measured to calculate hip stiffness coefficients at holding traction (k-hold) and maximal traction (k-max). We used multivariable regression analysis to determine whether postless arthroscopy was predictive of lower stiffness coefficients when controlling for other relevant patient-specific factors. RESULTS: Hip arthroscopy was performed with a post-based system in 105 patients and with a postless system in 51. Mean holding traction force (67.5 ± 14.0 kilograms-force [kgf] vs 55.8 ± 15.3 kgf) and mean maximum traction force (96.0 ± 16.6 kgf vs 69.9 ± 14.1 kgf) were significantly lower in the postless group. On multivariable analysis, postless traction was an independent predictor of decreased k-hold (ß = -31.4; 95% confidence interval, -61.2 to -1.6) and decreased k-max (ß = -90.4; 95% confidence interval, -127.8 to -53.1). Male sex, Beighton score of 0, and poor hamstring flexibility were also predictors of increased k-hold and k-max in the multivariable model. CONCLUSIONS: Postless traction systems decrease the amount of traction force required for adequate hip distraction for both maximal and holding traction forces when compared with post-based systems. Postless traction systems may help further reduce distraction-type neurologic injuries and pain after hip arthroscopy by lowering the traction force required to safely distract the hip. LEVEL OF EVIDENCE: Level III, prospective cohort-historical control comparative study.

Dual Approach to Talar Dome Increases Access for Fracture Care Without Osteotomy.

BACKGROUND: There is no consensus surgical treatment algorithm for talar body fractures, with authors recommending both soft tissue-only and osteotomy-based approaches. This study evaluates talar dome access via dual approaches to the talar dome through anterolateral transligamentous (ATL) and modified posteromedial (mPM) approaches. METHODS: Ten cadaveric legs (5 matched pairs) were included. An mPM approach, between flexor hallucis longus and Achilles tendon, and an ATL approach, utilizing the anterolateral interval with transection of anterior talofibular ligament and calcaneofibular ligament, were performed on each specimen. Order of approach was alternated within each pair. Accessible dome surface area (DSA) was outlined by drilling with a 1.6-mm Kirschner wire at the visualized talar dome margin both with and without 4 mm of tibiotalar distraction using an external fixator. Specimens were analyzed by computed tomography (CT). Primary outcome was accessible DSA. Student t tests compared DSA accessed by different exposure methods. RESULTS: An initial mPM approach exposed 25.6% and 33.6% of DSA without and with distraction (P = .002). An initial ATL approach accessed 47.0% and 58.1% of DSA without and with distraction, respectively (P = .003). Accessibility via dual approaches was 71.7% and 93% of DSA without and with distraction with an initial ATL approach and 71.3% and 87.5% of DSA without and with distraction with an initial mPM approach (P = .96 and .37, respectively). The central talar dome was inaccessible in an almond-shaped area, tapered at the medial and lateral ends. Anterior, lateral, and posterior articular margins were able to be fully exposed, often with overlapping exposure between posterior and anterior approaches, with distraction reliably improving lateral visualization. CONCLUSION: Dual approaches provided access to greater than 70% and 85% of talar DSA without and with distraction, respectively. Order of approach did not significantly affect exposure and thus should be determined by surgeon discretion. These results may promote soft tissue-only treatment strategies in talar body fracture care with an extensile exposure of the talar dome surface. Careful preoperative planning optimizes the advantages of this approach. LEVEL OF EVIDENCE: Level IV, case series.

Reformatting of Computed Tomography Scans Parallel to the S1 End Plate Increases Visualization of Trans Sacral Pathway in the First Sacral Segment, Especially With Dysmorphism.

OBJECTIVE: To determine whether reformatted computed tomography (CT) scans would increase surgeons' confidence in placing a trans sacral (TS) screw in the first sacral segment. SETTING: Level 1 trauma center. DESIGN: A retrospective cohort study. PATIENTS/PARTICIPANTS: There were 50 patients with uninjured pelvises who were reviewed by 9 orthopaedic trauma fellowship-trained surgeons and 5 orthopaedic residents. MAIN OUTCOME MEASUREMENTS: The overall percentage of surgeons who believe it was safe to place a TS screw in the first sacral segment with standard (axial cuts perpendicular to the scanner gantry) versus reformatted (parallel to the S1 end plate) CT scans. RESULTS: Overall, 58% of patients were believed to have a safe corridor in traditional cut axial CT scans, whereas 68% were believed to have a safe corridor on reformatted CT scans ( P < 0.001). When grouped by dysplasia, those without sacral dysplasia (n = 28) had a safe corridor 93% of the time on traditional scans and 93% of the time with reformatted CT scans ( P = 0.87). However, of those who had dysplasia (n = 22), only 12% were believed to have a safe corridor on original scans compared with 35% on reformatted scans ( P < 0.001). CONCLUSIONS: CT scan reformatting parallel to the S1 superior end plate increases the likelihood of identifying a safe corridor for a TS screw, especially in patients with evidence of sacral dysplasia. The authors would recommend the routine use of reformatting CT scans in this manner to provide a better understanding of the upper sacral segment osseous fixation pathways.

Animal models in compartment syndrome: a review of existing literature.

Objective: Extremity compartment syndrome (ECS) is a morbid condition resulting in permanent myoneural damage. Currently, the diagnosis of compartment syndrome relies on clinical symptoms and/or intracompartment pressure measurements, both of which are poor predictors of ECS. Animal models have been used to better define cellular mechanisms, diagnosis, and treatment of ECS. However, no standardized model exists. The purpose of this study was to identify existing animal research on extremity compartment syndrome to summarize the current state of the literature and to identify weaknesses that could be improved with additional research. Methods: A MEDLINE database search and reverse inclusion protocol were utilized. We included all animal models of ECS. Results: Forty-one studies were included. Dogs were the most commonly used model species, followed by pigs and rats. Most studies sought to better define the pathophysiology of compartment syndrome. Other studies evaluated experimental diagnostic modalities or potential treatments. The most common compartment syndrome model was intracompartment infusion, followed by tourniquet and intracompartment balloon models. Few models incorporated additional soft tissue or osseous injury. Only 65.9% of the reviewed studies confirmed that their model created myoneural injury similar to extremity compartment syndrome. Conclusions: Study purpose, methodology, and outcome measures varied widely across included studies. A standardized definition for animal compartment syndrome would direct more consistent research in this field. Few animal models have investigated the pathophysiologic relationship between traumatic injury and the development of compartment syndrome. A validated, clinically relevant animal model of extremity compartment syndrome would spur improvement in diagnosis and therapeutic interventions.

Talar Dome Access Through Posteromedial Surgical Intervals for Fracture Care.

BACKGROUND: Posterior talar body fractures are rare injuries without a consensus surgical approach. This study evaluates the accessible area of the talar dome through 2 posteromedial approach intervals (posteromedial [PM] and modified posteromedial [mPM]) both with and without distraction. METHODS: Ten male cadaveric legs (5 matched pairs) were included. A PM approach, between flexor hallucis longus (FHL) and the tibial neurovascular bundle, and an mPM approach, between FHL and Achilles tendon, was performed on each pair. In total, 4 mm of distraction across the tibiotalar joint was applied with the foot held in neutral position. Accessible dome surface area (DSA) was outlined by drilling with a 1.6-mm Kirschner wire with and without distraction. Specimens were explanted and analyzed by micro-computed tomography with 3-dimensional reconstruction. Primary outcomes were total accessible DSA and sagittal plane access at predetermined intervals. RESULTS: The PM approach allowed access to 19.1% of the talar DSA without distraction and 33.1% of the talar dome with distraction (P < .001). The mPM approach provided access to 20.4% and 35.6% of the talar DSA without and with distraction (P < .001). Both approaches demonstrated similar sagittal plane access at all intervals except the lateral border of the talus, where the mPM approach provided greater access both without distraction (20.5% vs 4.38%, P = .002) and with distraction (34.3% vs 17.8%, P = .02). CONCLUSION: The mPM approach, using an interval between FHL and Achilles tendon, provides similar access to the posterior surface of talar dome and better sagittal plane access to the most lateral portion of the dome. The mPM interval provides the advantage of avoiding direct dissection of the tibial nerve or posterior tibial artery. Using an external fixator for distraction can improve talar dome visualization substantially. LEVEL OF EVIDENCE: Level V, Cadaveric Study.

Biomechanical and anatomical considerations for dual plating of distal femur fractures: a systematic literature review.

INTRODUCTION: Distal femur fractures are challenging injuries historically associated with high rates of nonunion and varus collapse with operative management. As a result, clinical and research interest in dual plating (DP) of distal femur fractures has seen a dramatic increase in recent years. The purpose of this study was to systematically review the literature regarding vascular anatomy and biomechanics of distal femur fractures treated with DP constructs. MATERIALS AND METHODS: A systematic literature review of two medical databases (PubMed & Scopus) was performed to identify peer-reviewed studies on the anatomy and biomechanics regarding DP of distal femur fractures. A total of 1,001 papers were evaluated and 14 papers met inclusion criteria (6 anatomy and 8 biomechanics). Methodological quality scores were used to assess quality and potential bias in the included studies. RESULTS: In the biomechanical studies, DP constructs demonstrated greater axial and rotational stiffness, as well as less displacement and fewer incidences of failure compared to all other constructs. Vascular studies showed that the femoral artery crosses the mid-shaft femur approximately 16.0-18.8 cm proximal to the adductor tubercle and it is located on average 16.6-31.1 mm from the femoral shaft at this location, suggesting that medial plate application can be achieved safely in the distal femur. The methodological quality of the included studies was good for biomechanical studies (Traa score 79.1; range 53-92.5) and excellent for anatomical studies (QUACs score 81.9; range 69.0-88.5). CONCLUSIONS: Existing biomechanics literature suggests that DP constructs are mechanically stronger than other constructs commonly used in the treatment of distal femur fractures. Furthermore, medial distal femoral anatomy allows for safe application of DP constructs, even in a minimally invasive fashion. Dual plating should be considered for patients with distal femur fractures that have risk factors for instability, varus collapse, or nonunion.

Previous Arthroscopic Hip Surgery Increases Axial Distractibility Compared to the Native Contralateral Hip and May Suggest Instability.

PURPOSE: To compare intraoperative hip joint distractibility between hips that previously underwent arthroscopic surgery and the contralateral hip with no history of surgical manipulation. METHODS: Patients undergoing revision hip arthroscopy between April 2019 and December 2020, who previously underwent arthroscopic hip surgery for femoroacetabular impingement syndrome, were prospectively enrolled. Exclusion criteria were any contralateral hip surgery. Before instrumentation, fluoroscopic images of both hips were obtained at 25 lbs traction intervals up to 100 lbs. Total joint space was measured at each traction interval. Distraction was calculated as the difference between the baseline joint space and the total joint space at each subsequent traction interval. Wilcoxon signed ranks tests and McNemar tests were used to compare distraction between revision and native contralateral hips. RESULTS: Forty-seven patients were included. Mean distraction of operative hips was significantly greater than mean distraction of nonoperative hips at traction intervals of 50 lbs (2.13 vs 1.04 mm, P = .002), 75 lbs (6.39 vs 3.70 mm, P < .001), and 100 lbs (8.24 vs 5.39, P < .001). Mean total joint space of operative hips was significantly greater than mean total joint space of nonoperative hips at traction intervals of 50 lbs (6.60 vs 5.39 mm, P < .001), 75 lbs (10.86 vs 8.05 mm, P < .001), and 100 lbs (12.73 vs 9.73, P < .001). A greater percentage of operative hips achieved all distraction thresholds, in 2-mm intervals up to 10-mm, at each traction interval. CONCLUSIONS: In the majority of patients undergoing revision hip arthroscopy, previous arthroscopic hip surgery increases axial distractibility of the hip joint compared with the native contralateral hip at axial traction forces of 50-100 lbs. Increased axial distractibility following hip arthroscopy may be suggestive of hip instability and can be assessed on a stress examination with the patient under anesthesia. LEVEL OF EVIDENCE: III, case-control study.

Capsular Repair During Hip Arthroscopy Demonstrates Restoration of Axial Distraction Resistance in an in Vivo Intraoperative Testing Model.

BACKGROUND: Cadaveric models demonstrate that failure of hip capsular repair is dependent on the robustness of the repair construct. In vivo data on capsular repair construct efficacy are limited. We investigated the effect of a figure-of-8 capsular repair on hip distraction resistance relative to native and post-capsulotomy states. We hypothesized that an unrepaired capsulotomy would demonstrate increased axial distraction compared with the native state and that capsular repair would restore distraction resistance to native levels. METHODS: Patients undergoing primary hip arthroscopy by a single surgeon were prospectively enrolled between March 2020 and June 2020. Prior to any instrumentation, fluoroscopic images of the operative hip were obtained at 12.5-lbs (5.7-kg) traction intervals, up to 100 lbs (45.4 kg). Anterolateral, modified anterior, and distal anterolateral portals were established. Following interportal capsulotomy, labral repair, and osteochondroplasty, fluoroscopic images were reobtained at each traction interval. Capsular repair was performed with use of a figure-of-8 suture configuration. Traction was reapplied and fluoroscopic images were again obtained. Joint distraction distance was measured at each traction interval for all 3 capsular states. Anteroposterior pelvic radiographs were utilized to scale fluoroscopic images to obtain joint space measurements in millimeters. RESULTS: A total of 31 hips in 31 patients were included. Capsulotomy resulted in significant increases in distraction distance from 25 (11.3 kg) to 100 lbs of traction compared with both native and capsular repair states (all comparisons, p ≤ 0.017). Capsular repair yielded a significantly greater distraction distance compared with the native state at 37.5 lbs (17.0 kg; 5.49 versus 4.98 mm, respectively; p = 0.012) and 50 lbs (22.7 kg; 6.08 versus 5.35 mm; p < 0.001). The mean difference in distraction distance between native and capsular repair states from 25 to 100 lbs of traction was 0.01 mm. CONCLUSIONS: This in vivo model demonstrates that an unrepaired interportal capsulotomy significantly increases axial distraction distance compared with the native, intact hip capsule. Performing a complete capsular closure reconstitutes resistance to axial distraction intraoperatively. Future research should evaluate the in vivo effects and associated clinical outcomes of other published capsular repair techniques and assess the durability of capsular repairs over time.

Arthroscopic Hip Capsule Reconstruction for Anterior Hip Capsule Insufficiency in the Revision Setting.

Iatrogenic hip instability is increasingly recognized as a cause of persistent pain and disability after hip arthroscopy. Many authors currently advocate capsular repair to reduce postoperative instability. However, anatomic deficiencies in the anterosuperior capsule can prevent a functional capsular repair, particularly in the revision setting. Capsular reconstruction has been shown to restore biomechanical stabilization in cadaveric models and improve short-term patient outcomes in patients with primary hip arthroscopy failure. Arthroscopic hip capsular reconstruction is technically challenging, largely owing to complex suture management and difficulties with graft placement and sizing. This article describes the capsular reconstruction technique, detailing the technical aspects of anterosuperior capsular defect identification; capsular preparation; suture management; and dermal allograft sizing, preparation, and positioning.