Distal Metaphyseal Ulnar Shortening Osteotomy Fixation: A Biomechanical Analysis.

PURPOSE: Ulnar shortening osteotomy can be used to treat ulnar impaction syndrome and other causes of ulnar wrist pain. Distal metaphyseal ulnar shortening osteotomy (DMUSO) is one technique that has been proposed to reduce the complications seen with a diaphyseal USO or a wafer resection. However, to our knowledge, the optimal fixation construct for DMUSO has not been studied. We sought to characterize the biomechanical stiffness and rotational stability of different DMUSO constructs. METHODS: A DMUSO was performed on 40 human cadaveric ulnas using 4 different fixation constructs (10 specimens per group): one 3.0 mm antegrade screw; two 2.2 mm antegrade screws; one 3.0 mm retrograde screw; and two 2.2 mm retrograde screws. Biaxial testing using axial load and cyclical axial torque was performed until failure, defined as 10° of rotation or 2 mm displacement. Specimens were assessed for stiffness at failure. Bone density was assessed using the second metacarpal cortical percentage. RESULTS: Bone density was similar between all 4 testing groups. Of the 4 groups, the 2 antegrade screw group exhibited the highest rotational stiffness of 232 ± 102 Nm/deg. In paired analysis, this was significantly greater than 1 retrograde screw constructs. In multivariable analysis, 2-screw constructs were significantly stiffer than 1 screw and antegrade constructs were significantly stiffer than retrograde. Maximum failure torque did not differ with orientation, but 2 screws failed at significantly higher torques. CONCLUSION: Using 2 screws for DMUSO fixation constructs may provide higher stiffness and maximum failure torque, and antegrade screw constructs may provide more stiffness than retrograde constructs. CLINICAL RELEVANCE: Antegrade screw fixation using 2 screws may provide the strongest construct for DMUSO. Antegrade fixation may be preferred because it avoids violating the distal radioulnar joint capsule and articular surface of the ulna.

Trochanteric osteotomy for acetabular fracture fixation: a case series and literature review.

PURPOSE: This study examined osteotomy union and heterotopic ossification (HO) after performing digastric trochanteric osteotomies during open reduction and internal fixation (ORIF) of acetabular and combined femoral head fractures. Femoral head osteonecrosis and trochanteric screw removal were secondarily assessed. METHODS: Twenty-six patients treated at a Level I trauma center, from years 2003 to 2019, who received a digastric trochanteric osteotomy during acetabular and combined femoral head fracture ORIF through a posterior surgical approach were retrospectively identified. Osteotomies were fixed with two 3.5 mm cortical lag screws. Rates of osteotomy union, HO, femoral head osteonecrosis, and trochanteric screw removal were determined. RESULTS: All osteotomies went onto union without displacement or failure of fixation. Only three (12%) patients developed severe HO (modified-Brooker class III-IV). There were no instances of femoral head osteonecrosis and only one (7%) patient required trochanteric screw removal. CONCLUSIONS: The digastric trochanteric osteotomy heals reliably with low rates of severe HO, femoral head osteonecrosis, and screw removal for soft-tissue irritation. A review of the literature is presented and found comparable findings.

Orthobiologic Techniques for Surgical Augmentation.

General awareness and clinical utilization of orthobiologic therapy has increased sharply in the recent years. Orthobiologics can be defined as "biological materials and substrates that promote bone, ligament, muscle, and tendon healing." There are 3 major strategies by which orthobiologics are thought to augment tissue repair or native biologic potential: factor-based, cell-based, and biomechanical augmentation. The purpose of this review is to synthesize the recent literature on orthobiologic techniques for surgical augmentation, with focus on several key areas including meniscus repair, osteochondral grafting, and rotator cuff repair.

Antegrade Fixation of Distal Metaphyseal Ulnar Shortening Osteotomy.

The ulnar shortening osteotomy (USO) is a common procedure used to treat ulnar impaction syndrome secondary to static or dynamic ulnar-positive variance. There are many described techniques for the USO. The distal metaphyseal ulnar shortening osteotomy (DMUSO) with retrograde cannulated screw fixation was described to reduce complications seen with other techniques. Biomechanical analysis of fixation constructs demonstrates 2-screw constructs are significantly stiffer than 1 screw and antegrade constructs have similar or greater stiffness when compared with retrograde constructs. Here, we describe a technique of antegrade cannulated screw fixation for DMUSO that obviates the need for the disruption of the distal radioulnar joint for intra-articular exposure of the ulnar head. Similar to the traditional retrograde DMUSO technique, this construct may also decrease the risk of delayed union, symptomatic implants associated with diaphyseal osteotomies, and disruption of triangular fibrocartilaginous complex in wafer procedures.

Low profile fragment specific plate fixation of lateral tibial plateau fractures - A technical note.

PURPOSE: Precontoured plates used to stabilize lateral tibial plateau (LTP) fractures are limited in their ability to raft particular areas of the reconstructed articular surface. These implants also do not fit every individual's bony anatomy and can lead to soft tissue irritation. The purpose of this study was to evaluate fragment specific plate fixation of LTP fractures using generic small and mini fragment constructs. METHODS: This was a retrospective case series of LTP fractures treated with small fragment tubular and/or mini fragment plate constructs at a single Level I trauma center. Postoperative complications were recorded. Final radiographs were analyzed to determine union and interval subsidence of the articular surface and/or loss of reduction. RESULTS: All 19 LTP fractures healed without loss of reduction or implant failure. There was minimal interval subsidence of the LTP in all patients. There were no complications or reoperations for symptomatic implant removal within the given follow-up period. CONCLUSION: Fragment specific fixation of LTP fractures using small and mini fragment plates creates a lower profile construct that reliably maintains fracture reduction to union.

Gluteus Minimus Debridement During Acetabular Fracture Surgery Does Not Prevent Heterotopic Ossification-A Comparative Study.

OBJECTIVES: To compare rates of heterotopic ossification (HO) after acetabular fracture surgery, through a posterior approach, with and without gluteus minimus muscle (GMM) debridement. DESIGN: Retrospective comparative study. SETTING: Single academic Level I trauma center. PATIENTS: Ninety-four patients in the GMM preserved group and 42 patients in the GMM debrided group met inclusion criteria. INTERVENTION: GMM preservation or debridement during acetabular fracture surgery through a single-posterior approach. MAIN OUTCOME MEASUREMENTS: Primary outcomes were incidence and severity of HO. Reoperation for HO excision was assessed. Other risk factors for severe HO (Brooker class III-IV) were secondarily assessed using multivariable logistic regression analyses. Odds ratios (ORs) with 95% confidence intervals were calculated. The significance was set at P-value ≤ 0.05. RESULTS: There was no difference in the incidence or severity of HO between the debrided and preserved groups. Rates of reoperation for HO excision were comparable. American Society of Anesthesiologists physical status class (OR = 3.3), head injury (OR = 4.6), and abdominal injury (OR = 4.5) were associated with severe HO. CONCLUSION: GMM debridement was not associated with a decreased incidence of HO after acetabular fracture surgery. American Society of Anesthesiologists class is a novel risk factor associated with severe HO formation. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Lateral Distractor Use During Internal Fixation of Tibial Plateau Fractures Has a Minimal Risk of Iatrogenic Peroneal Nerve Palsy.

OBJECTIVES: To determine the incidence of iatrogenic peroneal nerve palsy after application of an intraoperative lateral distractor during open reduction and internal fixation of tibial plateau fractures. DESIGN: Retrospective review. SETTING: Single academic Level I trauma center. PATIENTS: One hundred forty-seven patients met criteria and were included in the study. INTERVENTION: Patients with unicondylar and bicondylar tibial plateau fractures underwent open reduction and internal fixation and received application of an intraoperative lateral distractor to aid in visualization and reduction of the impacted lateral plateau. MAIN OUTCOME MEASUREMENTS: Incidence of iatrogenic peroneal nerve palsy. RESULTS: There was a 2.0% incidence of iatrogenic peroneal nerve symptoms (3 of 147 patients), most of which were incomplete sensory deficits. There was no association with staged external fixation, regional anesthesia, or tourniquet use. CONCLUSION: Use of an intraoperative lateral distractor is safe and has a low incidence of iatrogenic peroneal nerve palsy if applied carefully. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.