Case report: unique failure of a Synthes TFNA fenestrated lag screw in a peritrochanteric nonunion.

Background: Intertrochanteric femur fractures are a common orthopaedic injury that are often treated surgically. Cephalomedullary nails (CMN) are frequently the implant of choice for intertrochanteric femur fractures, resulting in low complication rates. Implant failure is a rare but reported complication. Common locations of failure include the proximal nail aperture, distal screw holes, and implant shaft. In this case report, we describe a CMN failure pattern through fenestrated cephalic screw holes. Case: A 70-year-old female sustained an OTA 31A-2.2 peritrochanteric fracture during a motor vehicle collision. She was treated the following day with a Synthes Trochanteric Fixation Nail-Advanced CMN utilizing a fenestrated cephalic screw. There were no intraoperative complications. She was made non-weight bearing for 8 weeks after the procedure due to ipsilateral foot fractures. At 6 months follow-up she was noted to have a delayed union. 11 months postoperatively she suffered a ground level fall and the cephalic lag screw failed through its fenestrations, resulting in varus collapse of her fracture at the femoral neck. The patient then underwent nail extraction and salvage total hip arthroplasty. Conclusion: Cephalomedullary nail implant failure is presented with implant fracture propagation through a fenestrated cephalic screw. Cephalomedullary lag screw failure is rare and can be difficult to manage. It is important to monitor new implants for unique failure mechanisms.

Allergic dermatitis after knee arthroscopy with repeated exposure to Dermabond Prineo™ in pediatric patients: Two case reports.

BACKGROUND: Allergic contact dermatitis (ACD) secondary to Dermabond Prineo™ is rare, but documented. To our knowledge, there are no described reports of this ACD reaction within the pediatric population following arthroscopic surgery. CASE SUMMARY: We report two cases of pediatric ACD upon second exposure to Dermabond Prineo™ after knee arthroscopy. Both cases presented within two weeks of the inciting second exposure. The cases resolved with differing described combinations of sterile cleaning, diphenhydramine, and antibiotic administration. No long-term sequelae were found. CONCLUSION: This case report elucidates the rare complication of allergic dermatitis secondary to Dermabond Prineo™ repeat exposure use in pediatric arthroscopy.

Traumatic Lateral Knee Dislocation of a Well-Functioning Total Knee Arthroplasty: A Case of Medial Collateral Ligament Rupture.

Tibiofemoral dislocation can be a devastating complication after total knee arthroplasty. Much of the literature on tibiofemoral dislocations state they result from iatrogenic causes, with a very limited number of case reports on traumatic dislocation. Most of the time, these cases will require surgical revision and increased constraint to treat the inherent instability. In addition, collateral ligament disruption increases the complexity of the treatment algorithm for these patients. We report the case of a lateral tibiofemoral total knee arthroplasty dislocation with associated medial collateral ligament injury treated successfully without surgical interventions.

Role of the transverse ligament of the ulnar collateral ligament of the elbow: a biomechanical study.

BACKGROUND: The ulnar collateral ligament (UCL) complex of the elbow plays a primary role in valgus and posteromedial stability of the elbow. The anterior oblique ligament (AOL) of the UCL is believed to provide the majority of resistance to external forces on the medial elbow. The transverse ligament (TL) of the UCL is generally thought to have minimal contribution to the elbow's overall stability. However, recent studies have suggested a more significant role for the TL. The primary aim of this study was to identify the TL's contribution to the stability of the elbow joint in determining the joint stiffness and neutral zone variation in internal rotation. METHODS: Twelve cadaveric elbows, set at a 90° flexion angle, were tested by applying an internal rotational force on the humerus to generate a medial opening torque at the level of the elbow. The specimens were preconditioned with 10 cycles of humeral internal rotation with sinusoidal torque ranging from 0 to 5 Nm. Elbow stiffness measures and joint neutral zone were first evaluated in its integrity during a final ramp loading. The test was subsequently repeated after cutting the TL at 33%, 66%, and 100% followed by the AOL in the same fashion. RESULTS: The native UCL complex joint stiffness to internal rotation measured 1.52 ± 0.51 Nm/°. The first observable change occurred with 33% sectioning of the AOL, with further sectioning of the AOL minimizing the joint stiffness to 1.26 ± 0.32 Nm/° (P = .004). A 33% resection of the TL found an initial neutral zone variation of 0.376 ± 0.23° that increased to 0.771 ± 0.41° (P < .01) at full resection. These values were marginal when compared with the full resection of the AOL for which we have found 3.69 ± 1.65° (P < .01). CONCLUSION: The TL had no contribution to internal rotation elbow joint stiffness at a flexion angle of 90°. However, sequential sectioning of the TL was found to significantly increase the joint neutral zone when compared with the native cadaveric elbow at a flexion angle of 90°. This provides evidence toward the TL having some form of contribution to the elbow's overall stability.

Hip Arthroplasty Instability After Implantation of a Spinal Cord Stimulator.

A 46-year-old man with a left hip resurfacing that had been stable for over 5 years sustained a hip dislocation immediately after the implantation of a spinal cord stimulator (SCS). He continued to experience multiple episodes of instability after this initial event, requiring several revision hip arthroplasty surgeries with variable degrees of constraint. It was not until after SCS removal and prolonged hip spica casting that the patient returned to pain-free, independent ambulation. SCS implantation may affect spino-pelvic stability and alter the biomechanics of the hip after hip arthroplasty procedures. We present the unique case of a patient with a well-fixed hip resurfacing with no previous episodes of instability who experienced dislocation immediately after SCS implantation.

Atypical Mycobacterial Infections of the Upper Extremity.

Atypical mycobacterial infections of upper extremity synovial-lined structures are often misdiagnosed and unrecognized. Despite an increasing incidence, lack of physician awareness of these pathogens may result in considerable delay in diagnosis and management, potentially leading to permanent disability. The authors conducted a literature review and analyzed 31 cases of penetrating atypical mycobacterial infection to better understand the clinical characteristics and to evaluate their posttreatment complication rate compared with available literature. Medical records for culture-positive cases of tenosynovial or intra-articular atypical mycobacterial infections of the upper extremity that were treated were retrospectively reviewed. Treatment outcomes were analyzed against published case reviews and case series. Thirty-one cases of penetrating atypical mycobacterial infection were identified. Mycobacterium marinum (n=11) was the most common organism and was associated with aquatic exposure. Twenty-eight cases received empiric treatment, 17 of which received contraindicated treatment. Patients saw an average of 5 physicians prior to receiving an accurate diagnosis, and the mean time to diagnosis was 10 months. All cases received antibiotic treatment in addition to surgical management. Twenty cases (68%) failed treatment outcomes. Delay in diagnosis and inappropriate management of atypical mycobacterial infections may lead to a treatment failure rate that is higher than what has been reported in the literature. Mycobacterium avium and M fortuitum had significantly higher failure rates than other organisms. A high index of suspicion is required to make a diagnosis and prevent residual disability. [Orthopedics. 2018; 41(3):e383-e388.].