Evidence-based Risk Stratification for Sport Medicine Procedures During the COVID-19 Pandemic.

Orthopaedic practices have been markedly affected by the emergence of the COVID-19 pandemic. Despite the ban on elective procedures, it is impossible to define the medical urgency of a case solely on whether a case is on an elective surgery schedule. Orthopaedic surgical procedures should consider COVID-19-associated risks and an assimilation of all available disease dependent, disease independent, and logistical information that is tailored to each patient, institution, and region. Using an evidence-based risk stratification of clinical urgency, we provide a framework for prioritization of orthopaedic sport medicine procedures that encompasses such factors. This can be used to facilitate the risk-benefit assessment of the timing and setting of a procedure during the COVID-19 pandemic.

A review of the anterolateral ligament of the knee: current knowledge regarding its incidence, anatomy, biomechanics, and surgical dissection.

PURPOSE: To systematically review current literature on the anterolateral ligament (ALL) of the knee. METHODS: We searched the PubMed/Medline database for publications specifically addressing the ALL. We excluded studies not written in English, studies not using human cadavers or subjects, and studies not specifically addressing the ALL. Data extraction related to the incidence, anatomy, morphometry, biomechanics, and histology of the ALL and its relation to the Segond fracture was performed. RESULTS: The incidence of the ALL ranged from 83% to 100%, and this range occurs because of small discrepancies in the definition of the ALL's bony insertions. The ALL originates anterior and distal to the femoral attachment of the lateral collateral ligament. It spans the joint in an oblique fashion and inserts between the fibular head and Gerdy tubercle on the tibia. Exact anatomic and morphometric descriptions vary in the literature, and there are discrepancies regarding the ALL's attachment to the capsule and lateral meniscus. The ALL is a contributor to tibial internal rotation stability, and histologically, it exhibits parallel, crimped fibers consistent with a ligamentous microstructure. The footprint of the ALL has been shown to be at the exact location of the Segond fracture. CONCLUSIONS: The ALL is a distinct ligamentous structure at the anterolateral aspect of the knee, and it is likely involved in tibial internal rotation stability and the Segond fracture. LEVEL OF EVIDENCE: Level IV, systematic review of anatomic and imaging studies.

Strain pattern comparison of double- and single-bundle anterior cruciate ligament reconstruction techniques with the native anterior cruciate ligament.

PURPOSE: The purpose of this study was to dynamically assess the native strain patterns of the anteromedial bundle (AMB) and posterolateral bundle (PLB) of the anterior cruciate ligament (ACL) and compare these findings with graft bundle strain patterns after double-bundle (DB) ACL reconstruction with tibial fixation under 40 N of tension at 75 degrees knee flexion (AMB) and under 20 N of tension at 20 degrees knee flexion (PLB) and after single-bundle (SB) reconstruction with tibial fixation under 40 N of tension at 20 degrees knee flexion. METHODS: The mean strain pattern of the AMB and PLB of the native ACL of 4 cadaveric knees was measured via differential variable reluctance transducers and 2-dimensional kinematic analysis during passive manual knee flexion-extension under a constant axial compression load. Measurements were repeated after DB and SB ACL reconstruction. Celeration line assessments with a split-middle technique were performed to quantify percent strain/knee flexion-extension angle change at reciprocating bundle function transition points. RESULTS: The DB ACL reconstruction technique displayed reciprocating AMB and PLB strain patterns that more closely replicated those of the native ACL. The SB ACL reconstruction technique tended to replicate AMB strain patterns, suggesting poor bundle function differentiation. CONCLUSIONS: The DB ACL reconstruction with differential AMB and PLB tensioning more closely replicated native ACL strain patterns than the SB ACL reconstruction. The SB ACL reconstruction that we used closely simulated native ACL AMB strain patterns; however, PLB function was not restored. CLINICAL RELEVANCE: The DB ACL reconstruction more closely replicated the AMB and PLB strain patterns of the native ACL.

Novel approach for reconstruction of the posterolateral corner using a free tendon graft technique.

Injuries to the lateral collateral ligament (LCL) and posterolateral corner of the knee, particularly when combined with anterior cruciate or posterior cruciate ligament injuries, can result in profound symptomatic knee instability. Although many surgical improvements have been made in the reconstruction of anterior and posterior cruciate ligament injuries, reconstruction of the posterolateral corner has had less predictable results, with residual pathologic laxity especially in the chronic situation. This has stimulated many surgeons to recommend acute repair of posterolateral knee injuries. This article will briefly review the relevant surgical anatomy, present a summary of current reconstructive techniques for the posterolateral corner, and describe our preferred method for anatomic reconstruction of the posterolateral corner for chronic instability of the knee by recreating the LCL and popliteofibular ligament using either autogenous or allograft soft tissue and an interference screw technique. We do not use a transtibial tunnel but re-orientate the transfibular tunnel and utilize 2 femoral tunnels an the attempt to recreate the LCL and popliteus tendon. In a small clinical series, this has proven to restore varus rotation and external rotation patholaxities with a high degree of predictability.

The biomechanical evaluation of four fixation techniques for proximal biceps tenodesis.

PURPOSE: The purpose of this study was to compare the cyclic displacement and ultimate failure strength of 4 proximal biceps tendon tenodesis fixation methods: the open subpectoral bone tunnel (SBT) biceps tenodesis, the arthroscopic suture anchor (SA) tenodesis, the open subpectoral interference screw (SIS) fixation technique, and the arthroscopic interference screw (AIS) technique. TYPE OF STUDY: Biomechanical experimental control. METHODS: Twenty fresh-frozen cadaver shoulders were dissected free of soft tissues, leaving the proximal humerus and the proximal biceps tendon as a free graft. Specimens were randomized to 1 of 4 groups with 5 total specimens in each group. A proximal biceps tenodesis was performed according to the techniques listed above. The specimens were mounted for an axial pull of the biceps tendon on a servohydraulic materials testing system with a 100-N load cycled at 1 Hz for 5,000 cycles, followed by an axial load to failure test. Cyclic displacement, ultimate load to failure, and site of failure were recorded for each specimen. RESULTS: The mean cyclic displacement recorded for each experimental group was as follows: SBT group, 9.39 +/- 2.82 mm; AIS group, 5.26 +/- 2.60 mm; SIS group, 1.53 +/- 0.60 mm; and SA group, 3.87 +/- 2.11 mm. The mean ultimate failure loads after 5,000 cycles were as follows: SBT group, 242.4 +/- 51.33 N; AIS group, 237.6 +/- 27.58 N; SIS group, 252.4 +/- 68.63 N; and SA group, 164.8 +/- 37.47 N. Each specimen failed at the tenodesis site. CONCLUSIONS: The SBT group showed statistically significant greater displacement than the other tenodesis methods. There were no statistically significant differences in ultimate failure strength between any of the biceps tenodesis methods tested. CLINICAL RELEVANCE: The data serve as a guide to the surgeon performing a proximal biceps tenodesis in choosing a fixation method.

Treatment and results of sternoclavicular joint injuries.

Sternoclavicular joint injuries are uncommon. The anatomy is not familiar to most orthopaedic surgeons, and there is a high risk of both intraoperative catastrophic and postsurgical complications when performing surgery in this region. Anterior SC joint instability should primarily be treated conservatively. The patients should be informed that there is a high risk of persistent instability with nonoperative or operative care, but that the persistent instability will be well tolerated and have little functional impact in the vast majority. Therefore, operative intervention for anterior SC joint instability is mainly cosmetic in nature. Patients with posterior SC joint dislocations require an expeditious diagnosis and treatment, due to the proximity of the displaced medial clavicle to the great vessels. An early closed reduction will usually be stable. Operative stabilization must, however, be considered if the closed reduction is unsuccessful or there is persistent SC instability. SC joint stabilization should be performed with a soft tissue reconstruction, repairing both the costoclavicular ligaments and the SC capsular envelope.