Superiorly and transversely orienting the bicortical suspension device provides optimal anterolateral stability to the proximal tibiofibular joint: a finite-element study.

PURPOSE: Instability of the proximal tibiofibular joint (PTFJ) can be treated with bicortical suspension (BCS) fixation. However, the ideal location, orientation, and configuration to apply one or two BCS devices are not clear. METHODS: A finite-element model of the PTFJ was created from a female adult's CT dataset. Anterior and posterior ligaments at the PTFJ were modeled and suppressed to simulate stable and unstable joints. Fifty-six models simulated 56 device placements along guiding tunnel lines that connect eight entry locations on the fibular head to seven exit points on the anteromedial tibia. Doubling device stiffness created 56 more models. Combing any two placements created 1176 double-device configurations which were categorized to be crossed, divergent or parallel. Displacement of the fibular head relative to the fixed tibia under 100 N anterolateral and posteromedial forces was assessed. RESULTS: Different placements had 2.1-27.9 mm translation with 0.7-8.9° internal rotation under anterolateral loading, and 1.8-5.2 mm translation with 6.1-7.9° external rotation under posteromedial loading. More transverse and superior orientations were associated with smaller anterolateral translation; more posterior and superior entry locations were associated with smaller internal rotation. The median (IQR) reductions in anterolateral translation by doubling device stiffness and by adding a second device were 0.8 (IQR 0.5-1.0) and 0.8 (IQR 0-6.1) mm, respectively. The type of double-device configurations had no significant effect on fibular motion. CONCLUSION: Surgeons should drill the guiding tunnel superiorly and transversely to ensure the optimal restoration of the PTFJ anterolateral stability.

Clinical outcomes of a unique ulnar collateral ligament reconstruction hybrid technique with ulnar-sided suspensory fixation.

BACKGROUND: Ulnar collateral ligament reconstruction (UCLR) is the gold standard for treating ulnar collateral ligament injuries in throwing athletes who have failed conservative treatment. There are several described techniques that produce successful and reproducible outcomes. In addition, there is biomechanical evidence that supports hybrid fixation of the graft with a docking technique on the humeral side and suspensory fixation on the ulnar side. However, as of this writing there are no clinical studies that have reported results. This retrospective case series is the first of its kind to report on clinical outcomes following UCLR with hybrid suspensory fixation. METHODS: Fifty throwing athletes who underwent ULCR with hybrid suspensory fixation from 2010-2017 by one of 5 surgeons at a single institution were available at a median follow-up of 7 years. Return to sport, level of sport, and postoperative complications were recorded at final follow-up. RESULTS: A total of 50 patients were included in final analysis. Nearly all were able to return to sport at the same level or higher (48/50, 96%). One of these 50 athletes (2%) played professionally, 27 (54%) played collegiately, and 21 (42%) played at the high school level. Seven patients (14%) underwent reoperation following the index procedure. The median (interquartile range) Quick Disabilities of the Arm, Shoulder, and Hand questionnaire score was 0.098 (0-4.5) at final follow-up. CONCLUSION: Hybrid suspensory fixation is a safe and effective technique for UCLR in the throwing athlete. Throwers can expect to return to sport at a very high rate with low risks for postoperative complications.

Biomechanical Assessment of Bicortical Suspension Device Fixation for Proximal Tibiofibular Joint Instability: Single Versus Double Device.

BACKGROUND: Bicortical suspension device (BCSD) fixation treats proximal tibiofibular joint (PTFJ) instability in both the anterolateral and posteromedial directions. However, biomechanical data are lacking as to whether this technique restores the native stability and strength of the joint. PURPOSE: To test (1) if BCSD fixation restores the native stability and strength and (2) if using 2 devices is needed. STUDY DESIGN: Controlled laboratory study. METHODS: Sixteen pairs of fresh-frozen cadaveric specimens were obtained. Six pairs were assigned to the control group and 10 matched pairs assigned for transection to model PTFJ and subsequent BCSD fixation (one specimen with 1-device repair and the other with 2-device repair). Joint stability and strength were assessed by translating the fibular head relative to the fixed tibia either anterolaterally or posteromedially. Control specimens received 20 cycles of 0- to 2.5-mm joint displacement tests (subfailure) and then proceeded to load to failure (5 mm). For the experimental group, cyclic tests were repeated after ligament resection and after fixation. Forces and stiffness at 2.5- and 5-mm displacement were recorded for comparisons of joint strength and stability at subfailure and failure loads, respectively. RESULTS: After repair of anterolateral instability, both the single- and double-device fixations successfully restored near-native states, with no significant differences as compared with the intact group for forces at subfailure load (P = .410) or failure load (P = .397). Regarding posteromedial instability, single-device repair did not restore forces to the near-native state at subfailure load (intact: 92.9 N vs single: 37.4 N; P = .001) or failure load (intact: 170.7 N vs single: 70.4 N; P = .024). However, the double-device repair successfully restored near-native posteromedial forces at both subfailure load (P = .066) and failure load (P = .723). CONCLUSION: For treatment of the most common form of PTFJ instability (anterolateral), this cadaveric study suggests that 1 BCSD is sufficient to restore stability and strength. The current biomechanical results also suggest that 2 devices are needed for restoring PTFJ posteromedial stability and strength. Using 2 devices addresses both types of instability and provides more PTFJ posteromedial stability. CLINICAL RELEVANCE: The results suggest that 1 device should be used for treating anterolateral instability and 2 devices used for posteromedial instability based on the biomechanical study.

Outcomes after arthroscopic repair of rotator cuff tears in the setting of mild to moderate glenohumeral osteoarthritis.

BACKGROUND: Rotator cuff pathology is a very common source of shoulder pain. Similarly, osteoarthritis of the glenohumeral joint can cause shoulder pain and produce similar symptoms. Surgical management can be indicated for both pathologies, however, outcomes data is limited when examining rotator cuff repair (RCR) in the setting of glenohumeral arthritis (GHOA). Thus, this study sought to determine outcomes for patients who undergo RCR in the setting of GHOA. AIM: To evaluate if a relationship exists between outcomes of RCR in the setting of GHOA. METHODS: This was a retrospective analysis of patients who underwent arthroscopic rotator cuff repair with concurrent glenohumeral osteoarthritis between 2010-2017. Patients were stratified based on rotator cuff tear size and glenohumeral osteoarthritis severity. Cohorts were paired 1:1 with patients without glenohumeral osteoarthritis. Patients included had a minimum two year follow-up. Rate of conversion to total shoulder arthroplasty, complication rates following initial surgery, and patient-reported outcome measures were collected. RESULTS: A total of 142 patients were included. The number of patients that required total shoulder arthroplasty within two years after index surgery was low. 2/71 (2.8%) patients with GHOA, and 1/71 (1.4%) without GHOA. Following rotator cuff repair, both groups showed favorable patient-reported outcomes. CONCLUSION: Patients with glenohumeral osteoarthritis who underwent arthroscopic rotator cuff repair showed comparable outcomes to patients without glenohumeral osteoarthritis.

Imaging Pediatric Spondylolysis: A Systematic Review.

STUDY DESIGN: A systematic review. OBJECTIVE: The aim of this study was to provide an evidence-based recommendation for when and how to employ imaging studies when diagnosing back pain thought to be caused by spondylolysis in pediatric patients. SUMMARY OF BACKGROUND DATA: Spondylolysis is a common structural cause of back pain in pediatric patients. The radiologic methods and algorithms used to diagnose spondylolysis are inconsistent among practitioners. METHODS: A literature review was performed in PubMed and Cochrane databases using the search terms "spondylolysis," "pediatric," "adolescent," "juvenile," "young," "lumbar," "MRI," "bone scan," "CT," and "SPECT." After inclusion criteria were applied, 13 articles pertaining to diagnostic imaging of pediatric spondylolysis were analyzed. RESULTS: Ten papers included sensitivity calculations for comparing imaging performance. The average sensitivity of magnetic resonance imaging (MRI) with computed tomography (CT) as the standard of reference was 81.4%. When compared with single-photon emission CT (SPECT), the average sensitivity of CT was 85% and the sensitivity of MRI was 80%. Thirteen studies made a recommendation as to how best to perform diagnostic imaging of patients with clinically suspected spondylolysis. When compared with two-view plain films, bone scans had seven to nine times the effective radiation dose, while four-view plain films and CT were approximately double. Of the diagnostic methods examined, MRI was the most expensive followed by CT, bone scan, four-view plain films, and two-view plain films. CONCLUSION: Due to their efficacy, low cost, and low radiation exposure, we find two-view plain films to be the best initial study. With unusual presentations or refractory courses, practitioners should pursue advanced imaging. MRI should be used in early diagnosis and CT in more persistent courses. However, the lack of rigorous studies makes it difficult to formulate concrete recommendations. LEVEL OF EVIDENCE: 3.