Palmar Divergent Dislocation of the Scaphoid and Lunate.

Teaching Point: Palmar dislocation of the scaphoid and lunate is an extremely uncommon injury that warrants early diagnosis and treatment to avoid complications such as median nerve dysfunction, avascular necrosis, and premature osteoarthritis.

Avulsion Fracture of the Posterior Tibiofibular Syndesmosis.

Teaching Point: A posterior tibial lip fracture is a rare avulsion fracture at the tibial insertion of the posterior tibiofibular ligament that causes significant ankle instability and often requires surgical intervention.

Operative management of isolated posterior cruciate ligament injuries improves stability and reduces the incidence of secondary osteoarthritis: a systematic review.

PURPOSE: To evaluate the evidence for operative and non-operative management of isolated posterior cruciate ligament (PCL) injuries. METHODS: Using Pubmed, EMBASE and Cochrane databases, a systematic review was conducted of studies investigating the treatment of isolated PCL injuries published until July 2020. Quality assessment was performed with the Cochrane risk of bias tool (level I), the Newcastle-Ottowa Scale (level II-III) and the National Institute of Health quality assessment tool (level IV). Clinical outcome measures included residual laxity, return to sports, patient-reported outcome measures, subsequent articular degeneration and complications. RESULTS: Twenty-seven studies [23 case series, 2 case-control, 1 cohort study and 1 randomized controlled trial (RCT)] including 5197 patients (5199 knees) with a mean age of 29.5 ± 3.6 years (range 15-68) fulfilled the study requirements. Significantly less residual laxity was found after posterior cruciate ligament reconstruction (PCLR) compared to non-operative management (3.43 vs. 5.47 mm, CI: 1.84-2.23, p < 0.001). Both treatment modalities yielded satisfying functional outcomes and a high return to sports (64-77%, mean: 70.3, CI: 67.8-72.2). Osteoarthritis (OA) occurred less frequently following PCLR (21.5 vs. 44.1%, p < 0.001). CONCLUSION: In the absence of level I RCTs, this systematic review suggests that surgical management for selected isolated PCL injuries is a reasonable option to consider, especially when the surgeon aims at minimizing residual laxity and presumably secondary osteoarthritis. LEVEL OF EVIDENCE: IV.

M6-C prosthesis failure in hybrid construction : a double case report.

Cervical disc arthroplasty (CDA) is a well known treatment for single level cervical disc degeneration. In multi level disc degeneration anterior cervical disc fusion (ACDF) is often combined with a CDA. In this hybrid construction, motion is preserved at the level of the CDA. This will give less stiffness in the neck and decreases stress at the adjacent level. However, there is a lack of literature about the long term efficacy, safety and complication rate of CDA in hybrid constructions. In this article we present two cases of spontaneous destruction of a M6-C prosthesis in a hybrid construction 5 years after surgery. One reason seems to be the polymer sheath who is used in the M6 prosthesis. Degradation of this sheath causes foreign body reactions with osteolysis in the vertebral bodies. However, the increased mechanical loading at the adjacent levels on the CDA due to the fused vertebrae could also be one of the reasons.