Variations in the Anatomic Morphology of the Lateral Distal Tibia: Surgical Implications for Distal Tibial Allograft Glenoid Reconstruction

Parada, Stephen A.; Shaw, K. Aaron; Moreland, Colleen M.; Adams, Douglas R.; Chabak, Mickey S.; Provencher, Matthew T.

doi:10.1177/0363546518793880

Cited by 10 publications

(9 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As the lateral cortex is where the fibula articulates, the cortex has been found to have 3 distinct variations. Parada et al 10 reported type A tibias to have a flat contour and be an ideal graft. Type B tibias had a slight concavity of less than 5 mm of central depth and were determined to be acceptable grafts with the ability to retain most of the lateral cortex for fixation.…”

Section: Discussionmentioning

confidence: 99%

“…Type C grafts were felt to be unacceptable for use, as they had a deep concavity with a central depth of more than 5 mm, necessitating complete removal of the cortex for hardware fixation. 10 They found that almost 86% of distal tibias in an MRI study were either type A or B, leaving 14% of tibias deemed to be unacceptable (type C). A further analysis found that neither age, height, weight, sex, nor body mass index affected the ability to allow harvest of a standard-size DTA graft.…”

Section: Discussionmentioning

confidence: 99%

“…Unfortunately, the age and sex of the donors were not available, although previous studies have shown that the suitability of grafts is independent of these factors. 9 , 10 The DTA grafts were then secured to a polyurethane solid foam block with a density of 20 pounds per cubic foot and with a 2-mm epoxy laminate on 1 side (Sawbones; Pacific Research Laboratories). This model was used to recreate the scenario typical of anterior glenoid bone loss with a cancellous anterior glenoid and an intact posterior glenoid cortex.…”

Section: Methodsmentioning

confidence: 99%

“…The presence of articular cartilage and the similarity of the radius of curvature of the articular surface of the distal tibia to the glenoid makes the DTA graft an attractive alternative to other bony reconstruction procedures. 9 , 10 The graft is typically arranged with the medial cancellous portion of the distal tibia placed into compression against the glenoid, with the lateral cortex of the tibia used to secure fixation ( Figures 1 and 2 ). The lateral aspect of the distal tibia at the articular surface has known anatomic deviations that vary from a straight border to a concave surface.…”

mentioning

confidence: 99%

“…The lateral aspect of the distal tibia at the articular surface has known anatomic deviations that vary from a straight border to a concave surface. 9 , 10 A straight, or nearly straight, lateral border has been found in up to 85% of tibias in imaging studies that used magnetic resonance imaging (MRI). 10 The presence of a straight lateral border allows the surgeon to retain the lateral cortex of the tibia to place screws against during the reconstruction, whereas a concave border requires the cortex to be removed to create a straight border, rendering the graft completely cancellous.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Anterior Glenoid Reconstruction With Distal Tibial Allograft: Biomechanical Impact of Fixation and Presence of a Retained Lateral Cortex

Parada

Shaw

McGee‐Lawrence

et al. 2021

Orthopaedic Journal of Sports Medicine

Self Cite

View full text Add to dashboard Cite

Background: Glenoid reconstruction with distal tibial allograft (DTA) is a known surgical option for treating recurrent glenohumeral instability with anterior glenoid bone loss; however, biomechanical analysis has yet to determine how graft variability and fixation options alter the torque of screw insertion and load to failure. Hypothesis: It was hypothesized that retention of the lateral cortex of the DTA graft and the presence of a washer with the screw will significantly increase the maximum screw placement torque as well as the load to failure. Study Design: Controlled laboratory study. Methods: Whole, fresh distal tibias were used to harvest 28 DTA grafts, half of which had the lateral cortex removed and half of which had the lateral cortex intact. The grafts were secured to polyurethane solid foam blocks with a 2-mm epoxy laminate to simulate a glenoid with an intact posterior glenoid cortex. Grafts underwent fixation with 4.0-mm cannulated drills, and screws and washers were used for half of each group of grafts while screws alone were used for the other half, creating 4 equal groups of 7 samples each. A digital torque-measuring screwdriver recorded peak torque for screw insertion. Constructs were then tested in compression with a uniaxial materials testing system and loaded in displacement control at 100 mm/min until at least 3 mm of displacement occurred. Ultimate load was defined as the load sustained at clinical failure. Results: The use of a washer significantly improved the ultimate torque that could be applied to the screws (+cortex and +washer = 12.42 N·m [SE, 0.82]; –cortex and +washer = 10.54 N·m [SE, 0.59]) ( P < .0001), whereas the presence of the native bone cortex did not have a significant effect (+cortex and –washer = 7.83 N·m [SE, 0.40]; –cortex and –washer = 8.03 N·m [SE, 0.56]) ( P = .181). Conclusion: In a hybrid construct of fresh cadaveric DTA grafts secured to a foam block glenoid model, the addition of washers was more effective than the retention of the lateral distal tibial cortex for both load to failure and peak torque during screw insertion. Clinical Relevance: This biomechanical study is relevant to the surgeon when choosing a graft and selecting fixation options during glenoid reconstruction with a DTA graft.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%