Cement Augmentation in Sacroiliac Screw Fixation Offers Modest Biomechanical Advantages in a Cadaver Model.

BACKGROUND: Sacroiliac screw fixation in elderly patients with pelvic fractures is prone to failure owing to impaired bone quality. Cement augmentation has been proposed as a possible solution, because in other anatomic areas this has been shown to reduce screw loosening. However, to our knowledge, this has not been evaluated for sacroiliac screws. QUESTIONS/PURPOSES: We investigated the potential biomechanical benefit of cement augmentation of sacroiliac screw fixation in a cadaver model of osteoporotic bone, specifically with respect to screw loosening, construct survival, and fracture-site motion. METHODS: Standardized complete sacral ala fractures with intact posterior ligaments in combination with ipsilateral upper and lower pubic rami fractures were created in osteoporotic cadaver pelves and stabilized by three fixation techniques: sacroiliac (n = 5) with sacroiliac screws in S1 and S2, cemented (n = 5) with addition of cement augmentation, and transsacral (n = 5) with a single transsacral screw in S1. A cyclic loading protocol was applied with torque (1.5 Nm) and increasing axial force (250-750 N). Screw loosening, construct survival, and sacral fracture-site motion were measured by optoelectric motion tracking. A sample-size calculation revealed five samples per group to be required to achieve a power of 0.80 to detect 50% reduction in screw loosening. RESULTS: Screw motion in relation to the sacrum during loading with 250 N/1.5 Nm was not different among the three groups (sacroiliac: 1.2 mm, range, 0.6-1.9; cemented: 0.7 mm, range, 0.5-1.3; transsacral: 1.1 mm, range, 0.6-2.3) (p = 0.940). Screw subsidence was less in the cemented group (3.0 mm, range, 1.2-3.7) compared with the sacroiliac (5.7 mm, range, 4.7-10.4) or transsacral group (5.6 mm, range, 3.8-10.5) (p = 0.031). There was no difference with the numbers available in the median number of cycles needed until failure; this was 2921 cycles (range, 2586-5450) in the cemented group, 2570 cycles (range, 2500-5107) for the sacroiliac specimens, and 2578 cycles (range, 2540-2623) in the transsacral group (p = 0.153). The cemented group absorbed more energy before failure (8.2 × 105 N*cycles; range, 6.6 × 105-22.6 × 105) compared with the transsacral group (6.5 × 105 N*cycles; range, 6.4 × 105-6.7 × 105) (p = 0.016). There was no difference with the numbers available in terms of fracture site motion (sacroiliac: 2.9 mm, range, 0.7-5.4; cemented: 1.2 mm, range, 0.6-1.9; transsacral: 2.1 mm, range, 1.2-4.8). Probability values for all between-group comparisons were greater than 0.05. CONCLUSIONS: The addition of cement to standard sacroiliac screw fixation seemed to change the mode and dynamics of failure in this cadaveric mechanical model. Although no advantages to cement were observed in terms of screw motion or cycles to failure among the different constructs, a cemented, two-screw sacroiliac screw construct resulted in less screw subsidence and greater energy absorbed to failure than an uncemented single transsacral screw. CLINICAL RELEVANCE: In osteoporotic bone, the addition of cement to sacroiliac screw fixation might improve screw anchorage. However, larger mechanical studies using these findings as pilot data should be performed before applying these preliminary findings clinically.

Sagittal Angulation and the Treatment of Geriatric Femoral Neck Fractures: Time to Update our Classification Systems.

OBJECTIVES: Inconsistent outcomes have been reported for percutaneous fixation of Garden I/II femoral neck fractures in geriatric patients. It was hypothesized that accounting for variable follow-up would better estimate the failure rate of percutaneous fixation with and without significant sagittal angulation. DESIGN: Retrospective. SETTING: Single academic healthcare system. PATIENT SELECTION CRITERIA: Patients ≥50 years of age treated with percutaneous screw fixation of Garden I/II (OTA/AO B1.1/B1.2) femoral neck fractures from 2010 to 2020 were identified. Pathologic fractures and open approaches were excluded. OUTCOME MEASURES AND COMPARISONS: Sagittal angulation was measured using a previously described method. 11 Treatment failure was defined as early fixation failure (within 6 weeks), nonunion, and/or avascular necrosis. Potential associations between treatment failure and patient, injury, and treatment variables were assessed. Cox proportional hazard analysis accounted for variable follow-up when assessing for event-free survival. RESULTS: Of the 240 fractures that met inclusion criteria, there were 20 treatment failures (8%) and 33 fractures with sagittal angulation ≥20 degrees on lateral radiographs (14%). Failure-free survival at 2 years was 91% for patients with <20 degrees of posterior angulation and 52% for patients with ≥20 degrees of posterior angulation ( P < 0.0001). The hazard ratio, which incorporates variable follow-up, for failure with ≥20 degrees of posterior angulation was 6.36 ( P < 0.0001). No other factors were associated with treatment failure. CONCLUSIONS: Significant posterior angulation (≥20 degrees) of Garden I/II femoral neck fractures is associated with a high failure rate after screw fixation. The authors suggest characterizing fractures with ≥20 degrees of sagittal angulation as Garden III fractures to better support surgical decision making. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Stable Lateral Compression Pelvic Ring Injury Requiring Operative Treatment due to Bladder Impingement: A Case Report.

CASE: A 25-year-old man sustained a stable lateral compression Type I (LC I) pelvic ring injury upon missing the landing of a downhill ski jump. He presented with painful voiding from a displaced bony fragment, partially impaling the bladder wall. With operative fixation of the fracture and urologic co-management, the patient had excellent outcomes at 1-year follow-up. CONCLUSION: We describe a rare urologic injury in the setting of an LC I pelvic ring injury. In the setting of an otherwise stable pelvic ring injury, careful review of imaging, detailed clinical history, and physical examination remain critical to optimizing patient outcomes.

Defining Posterior Wall Fragments in Associated Both Column Acetabular Fractures (OTA/AO 62C).

OBJECTIVE: Associated both column acetabular fractures (OTA/AO 62C) with concomitant posterior wall fracture fragments (ABC + PW) have not been well-defined. The purpose of this study was to report on the incidence and morphology of ABC + PW fractures. METHODS: A retrospective review of associated both column (ABC) fractures between 2014 and 2020 was performed. Computed tomography scans including 3-D surface rendered reformats for each were reviewed to determine whether a posterior wall (PW) fragment was present and its morphologic characteristics. RESULTS: One hundred fifty-two ABC fractures were identified. Sixty-two fractures (41%) were identified as ABC + PW. 3D-computed tomographies were available on 58 fractures. Morphologic analysis was performed based on the relationship of the fracture to the gluteal pillar. Twenty PW fragments were posterior to the gluteal pillar, 19 extended into the gluteal pillar, and 19 extended anterior. Fifty-two fractures were treated with operative fixation; 32 (62%) were clamped and fixed with screws from the same anterior approach whereas 15 (29%) required a separate posterior approach; and no fixation was placed in 5 (9%). 29 of 32 PW fragments (91%) requiring fixation that extended into or anterior to the pillar were fixed from the anterior approach, and 7 of 15 posterior fractures (47%) required a separate posterior approach. CONCLUSIONS: A separate PW fragment was identified in 41% of ABC fractures. Their variation in morphology can be classified into 3 types based on the relation to the gluteal pillar that has potential implications for treatment from the anterior approach compared with requiring a separate posterior approach. We suggest these data could be used to update the 2018 OTA/AO Fracture Compendium. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The Ilioinguinal Surgical Approach Using a Modified Medial Window: Origin, Evolution, and Applications. A 34-Year Perspective.

Emile Letournel's ilioinguinal approach provided unprecedented surgical access to the anterior aspect of the innominate bone. A refinement of this approach is described which incorporates a modified medial window that limits dissection around the external iliac vessels, expands surgical exposure of the anterior pelvic ring, and provides additional reduction possibilities while preserving the capabilities of the lateral and middle windows.

A Variant of the Sciatic Nerve and its Clinical Implications.

Variants of gluteal neural anatomy are important to consider, especially during surgical approaches to the hip. During the routine dissection of the gluteal region, a variant of the sciatic nerve was found where the nerve left the pelvis fully split into its tibial and common fibular components. Intrapelvically and extrapelvically, there was no splitting of the two components by the piriformis muscle. Distally, the two parts of the nerve were draped over the medial and lateral edges of the ischial tuberosity. To avoid iatrogenic injury to the sciatic nerve during invasive or surgical approaches to this region, all possible anatomical variations, such as the one presented herein, should be appreciated by the clinician.

Is Early Definitive Fixation of Bicondylar Tibial Plateau Fractures Safe? An Observational Cohort Study.

OBJECTIVES: The optimal treatment protocol for bicondylar plateau fractures remains controversial. Contrary to popular practice which favors a staged protocol in many high-energy fracture patterns, we have used early single-stage open reduction and internal fixation (ORIF) to treat these injuries whenever possible. The purpose of this study was to determine the complication rate and the functional and radiographic outcomes of this strategy. DESIGN: Retrospective cohort study and prospective data collection. SETTING: Level I trauma center. PATIENTS/PARTICIPANTS: One hundred one patients with 102 OTA/AO type 41-C bicondylar tibial plateau fractures were treated with early definitive ORIF, defined as nonstaged surgery performed within 72 hours from injury. A subset of patients was part of a longitudinal study and reported functional outcomes at 1 year. INTERVENTION: Early definitive ORIF. MAIN OUTCOME MEASUREMENT: Primary outcome: reoperation rate, defined as any surgery within 12 months after the index operation; secondary outcomes: quality and stability of radiographic fracture reduction; and functional outcome [Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) and short musculoskeletal functional assessment (SMFA)]. RESULTS: Nonstaged operative treatment of bicondylar plateau fractures was performed in 91.3% of the fractures during the study period. For those, early definitive ORIF (surgery within 72 hours from injury) was performed in 82.3% fractures. Mean time from injury to ORIF, for closed fractures, was 29.8 hours. Sixteen (15.7%) fractures, which were treated with early definitive ORIF, required an additional surgical procedure within 12 months. Complications included wound infection requiring surgical management, compartment syndrome requiring fasciotomies, nonunion, early fixation failure, and implant removal for discomfort. The reoperation rate was 12.7% if implant removal was excluded. At least 3 of the 4 radiographic criteria used to assess the adequacy of reduction were achieved in 95.1% of cases, and all 4 criteria were met in 59.8% of fractures. The Physical Component of the SF-36 at 12 months was 42.6, which is comparable to values reported in previous studies for operative treatment of bicondylar plateau fractures. CONCLUSIONS: In a model where surgery is performed without delay by experienced orthopaedic trauma surgeons, a large proportion of bicondylar tibial plateau fractures can be safely treated with early definitive ORIF. Early surgery was associated with satisfactory postoperative radiographic reductions. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.