Genomic Features and Classification of Homologous Recombination Deficient Pancreatic Ductal Adenocarcinoma.

BACKGROUND AND AIMS: Homologous recombination deficiency (HRD) in pancreatic ductal adenocarcinoma (PDAC), remains poorly defined beyond germline (g) alterations in BRCA1, BRCA2, and PALB2. METHODS: We interrogated whole genome sequencing (WGS) data on 391 patients, including 49 carriers of pathogenic variants (PVs) in gBRCA and PALB2. HRD classifiers were applied to the dataset and included (1) the genomic instability score (GIS) used by Myriad's MyChoice HRD assay; (2) substitution base signature 3 (SBS3); (3) HRDetect; and (4) structural variant (SV) burden. Clinical outcomes and responses to chemotherapy were correlated with HRD status. RESULTS: Biallelic tumor inactivation of gBRCA or PALB2 was evident in 43 of 49 germline carriers identifying HRD-PDAC. HRDetect (score ≥0.7) predicted gBRCA1/PALB2 deficiency with highest sensitivity (98%) and specificity (100%). HRD genomic tumor classifiers suggested that 7% to 10% of PDACs that do not harbor gBRCA/PALB2 have features of HRD. Of the somatic HRDetecthi cases, 69% were attributed to alterations in BRCA1/2, PALB2, RAD51C/D, and XRCC2, and a tandem duplicator phenotype. TP53 loss was more common in BRCA1- compared with BRCA2-associated HRD-PDAC. HRD status was not prognostic in resected PDAC; however in advanced disease the GIS (P = .02), SBS3 (P = .03), and HRDetect score (P = .005) were predictive of platinum response and superior survival. PVs in gATM (n = 6) or gCHEK2 (n = 2) did not result in HRD-PDAC by any of the classifiers. In 4 patients, BRCA2 reversion mutations associated with platinum resistance. CONCLUSIONS: Germline and parallel somatic profiling of PDAC outperforms germline testing alone in identifying HRD-PDAC. An additional 7% to 10% of patients without gBRCA/PALB2 mutations may benefit from DNA damage response agents.

Telemedicine-guided forearm emergency decompressive fasciotomy for compartment syndrome.

INTRODUCTION: We highlight the utility of telemedicine and telementoring for the management of orthopaedic emergencies using a case of forearm compartment syndrome following a penetrating trauma in a northern Inuit community in Nunavik, Quebec, Canada. METHODS & RESULTS: As in many cases of compartment syndrome in rural settings, the patient was at a high risk of developing irreversible complications. A prompt diagnosis followed by an emergency decompressive fasciotomy was warranted. Using telemedicine and telementoring guidance, the diagnosis of compartment syndrome was made, and the patient's volar compartment was successfully decompressed by a local emergency physician in a timely manner. Subsequently, the patient was able to be safely transferred to a level 1 trauma centre for further surgical management. This included a second-look operative exploration, irrigation and debridement, completion of volar fasciotomy and ulnar nerve decompression. No complications were seen. DISCUSSION: Our experience highlights two important clinical implications. First, telemedicine can be successfully implemented to facilitate clinical diagnosis of surgical emergencies in the rural setting. Second, telementoring can effectively allow surgeons to guide physicians remotely to perform emergency decompressive fasciotomy, which can help salvage the affected limb and significantly decrease the risk of debilitating complications.

Growth Modulation for the Treatment of Juvenile Hallux Valgus: A Systematic Review of Literature.

Background: Juvenile hallux valgus (JHV) is a forefoot deformity that causes pain and functional limitation. Treatment poses a challenge in terms of the optimal technique and timing of intervention. A systematic review of the literature on the use of growth modulation in treating JHV was conducted. Materials and methods: The literature review was performed using PubMed and EMBASE searches for articles investigating growth modulation in the treatment of JHV published before December 1st, 2021. Seven articles were included in the final review that matched the inclusion and exclusion criteria. The primary outcomes included the degree of correction of hallux valgus angle and intermetatarsal angle. A qualitative assessment of the articles was done due to the heterogeneity of the growth modulation methods used in these articles. Results: A total of 135 feet from 78 patients were included from the reviewed articles. Growth modulation methods included temporary screw lateral hemiepiphysiodesis of the first metatarsal, lateral drilling hemiepiphysiodesis of the first metatarsal, and a trephine plug removal of the lateral epiphysis followed by cancellous bone graft insertion. The degree of correction of the hallux valgus and intermetatarsal angles were found to be statistically significant in all studies, regardless of the technique. Conclusion: Growth modulation for JHV by lateral hemiepiphysiodesis using minimally invasive techniques produced favourable radiologic outcomes with some evidence of clinical improvement. Larger, prospective and comparative studies with objective clinical outcome measures may further consolidate this surgical approach as a mean to treating this deformity. How to cite this article: AlZeedi M, Park JP, Marwan Y, et al. Growth Modulation for the Treatment of Juvenile Hallux Valgus: A Systematic Review of Literature. Strategies Trauma Limb Reconstr 2023;18(1):51-55.

Patellofemoral Instability Part I: Evaluation and Nonsurgical Treatment.

Patellofemoral instability (PFI) is a prevalent cause of knee pain and disability. It affects mostly young females with an incidence reported as high as 1 in 1,000. Risk factors for instability include trochlear dysplasia, patella alta, increased tibial tubercle-to-trochlear groove distance, abnormal patella lateral tilt, and coronal and torsional malalignment. Nonsurgical and surgical options for PFI can treat the underlying causes with varied success rates. The goal of this review series was to synthesize the current best practices into a concise, algorithmic approach. This article is the first in a two-part review on PFI, which focuses on the clinical and radiological evaluation, followed by nonsurgical management. The orthopaedic surgeon should be aware of the latest diagnostic protocol for PFI and its nonsurgical treatment options, their indications, and outcomes.

Arthroscopic management of synovial chondromatosis of the shoulder: a systematic review of literature.

Background: Synovial chondromatosis (SC) of the shoulder is rare, with limited literature on its management. This systematic review of literature aimed to characterize common arthroscopic techniques for the treatment of shoulder SC and patient outcomes. We hypothesized that arthroscopy is an effective operative modality for the management of shoulder SC. Methods: PubMed and Embase databases were searched for articles on arthroscopic management of shoulder SC, published before 6 August 2020. All articles meeting inclusion criteria received an independent full-text review by two authors. Results: An initial search found 64 articles. Following duplicate removal and title, abstract, and full-text reviews, 27 articles (48 patients) remained eligible. The mean age of patients was 33.0 years, with 2:1 male-to-female ratio. The mean follow-up was 41.8 months. SC was found to affect various intra- and extra-articular locations of the shoulder. Overall, arthroscopic treatment of shoulder SC was successful in 70.8%. Treatment failure was common in SC involving the bicipital tendon sheath. Disease recurrence was seen in 14.7%. Conclusion: Literature on arthroscopic management of shoulder SC is limited, and significant heterogeneity in arthroscopic techniques was observed. Although arthroscopic management of shoulder SC is effective, further optimization is necessary to minimize treatment failure and disease recurrence.

Two Cases of Polyethylene Granuloma After Distal Femoral Endoprosthesis With All-Polyethylene Tibia.

Limited literature exists on complications specific to the all-polyethylene tibial component in distal femoral replacement (DFR). Unlike in primary arthroplasty with polyethylene components, polyethylene granuloma has not been reported in DFR with an all-polyethylene tibia. Here, we report 2 cases of polyethylene granuloma in patients with primary bone sarcoma who underwent DFR with an all-polyethylene tibia. Radiologically, evidence of intraosseous granuloma formation and periprosthetic osteolysis was observed at the anterior tibial metaphysis. Both patients underwent an operative debridement of polyethylene granuloma and necrotic tissues, followed by a revision to a long-stem, cemented metal-backed tibia with impacted allograft to fill the defect. Polyethylene granuloma should be considered a differential diagnosis in the presence of a periprosthetic lytic lesion after DFR with an all-polyethylene tibial component.

An Arthroscopic Procedure for Restoration of Posterolateral Tibial Plateau Slope in Tibial Plateau Fracture Associated With Anterior Cruciate Ligament Injuries.

High-energy anterior cruciate ligament (high-energy ACL) injury, occurring in high-energy rotatory trauma of the knee, can accompany a unique fracture pattern that involves depression of the slope of the posterolateral tibial plateau (PLTP). These injuries are challenging to manage due to the lack of a gold-standard arthroscopic procedure that addresses both ACL deficiency and depressed PLTP slope. In such injuries, a one-stage approach may be used to (1) reconstruct the ACL or (2) reduce and fix the avulsed tibial spine, while concomitantly performing an arthroscopy-assisted reduction of a PLTP fracture that restores the anatomic slope of the tibial plateau. To summarize, using combined arthroscopic and fluoroscopic visualization, a tibial tunnel reaching 1 cm distal to the depressed plateau fragment is created using a cannulated drill. The drill is used to punch up the depressed fragment to its anatomic location, restoring the original slope of the PLTP. The corrected slope is then fixed in situ using a press-fit fibular allograft to stabilize the corrected PLTP slope. Use of this minimally invasive arthroscopic technique to restore the PLTP slope may help prevent graft failure of the reconstructed ACL and improve patient outcomes.