Background: Large (4.5 mm) and/or transpatellar bone tunnels have been associated with patellar fracture after medial patellofemoral ligament (MPFL) reconstruction. To avoid this outcome, many surgeons now employ suture anchors to affix the MPFL graft to the patella. Purpose: To evaluate the risk of patellar fracture and other outcomes associated with smaller (3.2-mm), short, oblique patellar tunnels as compared with suture anchor fixation in MPFL reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: A single institution’s electronic medical record was queried for all patients undergoing MPFL reconstruction between March 2010 and December 2018. A chart review of operative reports was utilized to identify those who had undergone MPFL reconstruction. Patients undergoing revision MPFL reconstruction or reconstruction with fully transpatellar bone tunnels were excluded. The incidence of patellar fracture and outcomes were evaluated from chart review. The mean duration of follow-up was >2 years. Results: A total of 384 knees in 352 patients undergoing primary MPFL reconstruction were identified. Small (3.2-mm), short, oblique tunnels were used for patellar fixation in 215 cases, and suture anchors were utilized in 169 cases. The small, oblique tunnels and suture anchor techniques both resulted in a low incidence of patellar fracture, with rates of 0.47% and 0%, respectively. The use of suture anchors was associated with an increased risk of subluxation or dislocation compared with small, oblique tunnels (odds ratio, 3.98; P = .028). No significant difference was found in the need for revision MPFL reconstruction surgery with suture anchors (odds ratio, 1.925; P = .66). Conclusion: The use of small, oblique tunnels with hamstring autograft is a safe means of patellar fixation in MPFL reconstruction. The use of small, oblique tunnels for patellar fixation versus 2 suture anchors can result in material cost savings with no significantly increased risk for fracture as well as an overall reduction in complication rates.

This study proposes and assesses a methodology to obtain high-quality probabilistic predictions and uncertainty information of near-landfall tropical cyclone(TC)-driven storm tide and inundation with limited time and resources. Forecasts of TC track, intensity, and size are perturbed according to quasi-random Korobov sequences of historical forecast errors with assumed Gaussian and uniform statistical distributions. These perturbations are run in an ensemble of hydrodynamic storm tide model simulations. The resulting set of maximum water surface elevations are dimensionality reduced using Karhunen-Lo`eve expansions and then used as a training set to develop a Polynomial Chaos (PC) surrogate model from which global sensitivities and probabilistic predictions can be extracted. The maximum water surface elevation is extrapolated over dry points incorporating energy head loss with distance to properly train the surrogate for predicting inundation. We find that the surrogate constructed with 3rd order PCs using Elastic Net penalized regression with Leave-One-Out cross-validation provides the most robust fit across training and test sets. Probabilistic predictions of maximum water surface elevation and inundation area by the surrogate model at 48-hour lead time for three past U.S. landfalling hurricanes (Irma 2017, Florence 2018, and Laura 2020) are found to be reliable when compared to best-track hindcast simulation results, even when trained with as few as 19 samples. The maximum water surface elevation is most sensitive to perpendicular track-offset errors for all three storms. Laura is also highly sensitive to storm size and has the least reliable prediction.

No abstract

Previous studies have demonstrated the benefits of 2-and 4-tine staple fixation in scapholunate interosseous ligament (SLIL) reconstruction, including improved rotational control and avoidance of the articular surface. This study compared scaphoid and lunate kinematics after SLIL fixation with traditional Kirschner wire (K-wire) fixation or 2-tine staple fixation. Methods: Eight fresh frozen cadaver arms with normal scapholunate (SL) intervals were included. Infrared motion capture was used to assess kinematics between the scaphoid and lunate as the wrists were moved through a simulated dart-throw motion. Kinematic data were recorded for each wrist in 4 states: SLIL intact, SLIL sectioned, K-wire fixation across SL interval and scaphocapitate joint, and 2-tine Nitinol staple fixation across SL interval. Strength of the SL staple fixation was evaluated using an axial load machine to assess load to failure of the staple construct. Results: Range of motion of the scaphoid and lunate with SLIL intact and SLIL sectioned were similar. Kwire fixation across the SL interval significantly decreased the overall wrist range of motion as well as scaphoid and lunate motion in all planes except for scaphoid flexion. Conversely, scaphoid and lunate motion after staple fixation was similar to that in normal wrists, except for a significant decrease in scaphoid extension. Under axial load simulating a ground-level fall, 3 of 8 arms demonstrated no failure, and none of the failures was due to direct failure of the 2-tine staple. Conclusions: This study demonstrates 2-tine staple fixation across the SL interval is effective in providing initial stability and maintaining physiologic motion of the scaphoid and lunate compared with K-wire fixation after SLIL injury. Clinical relevance: This study demonstrates an alternate technique for the stabilization of the SL interval in repair of acute SLIL injuries using 2-tine staple fixation, which maintains near physiologic motion of the scaphoid and lunate after SLIL injury.