Background: Lesser toe plantar plate attenuation or disruption is being increasingly implicated in a variety of common clinical conditions. A multitude of surgical techniques and devices have been recently developed to facilitate surgical repair of the plantar plate. However, the microvascular anatomy, and therefore the healing potential in large part, has not been defined. We investigated the microvasculature of the plantar plate by employing a novel technique involving microvascular perfusion and nano–computed tomography (nano-CT) imaging. Methods: Twelve human adult cadaveric lower extremities were amputated distal to the knee. The anterior and posterior tibial arteries were perfused with a barium solution. The soft tissues of each foot were then counterstained with phosphomolybdic acid (PMA). The second through fourth toe metatarsophalangeal (MTP) joints of 12 feet were imaged with nano-CT at 14-micron resolution. Images were then reconstructed for analysis of the plantar plate microvasculature and calculation of the vascular density along the length of the plantar plate. Results: A microvascular network extends from the surrounding soft tissues at the attachments of the plantar plate on both the metatarsal and proximal phalanx. The midsubstance of the plantar plate appears to be relatively hypovascular. Analysis of the vascular density along the length of the plantar plate demonstrated a consistent trend with increased vascular density at approximately the proximal 29% and distal 22% of the plantar plate. Conclusion: There is a vascular network extending from the surrounding soft tissues into the proximal and distal attachments of the plantar plate. Clinical relevance: The hypovascular midportion of the plantar plate may play an important role in the underlying pathoanatomy and pathophysiology of this area. These findings may have significant clinical implications for the reparative potential of this region and the surgical procedures currently described to accomplish anatomic plantar plate repair.

Category: Basic Sciences/Biologics, Lesser Toes, Midfoot/Forefoot Introduction/Purpose: Lesser toe plantar plate attenuation or disruption is being increasingly implicated in a variety of very common clinical complaints including metatarsalgia, metatarsal-phalangeal (MTP) joint subluxation and dislocation, hammertoe, crossover toe, etc. A multitude of surgical techniques and devices have been recently developed to facilitate surgical repair of the plantar plate. However, the microvascular anatomy, and therefore the healing potential in large part, has not been addressed. We sought to answer this question by employing a novel technique involving microvascular perfusion and nano-computed tomography (Nano-CT) imaging. Methods: 12 human adult cadaveric lower extremities were amputated distal to the knee. The anterior and posterior tibial arteries were dissected and cannulated proximal to the ankle joint and were perfused with a barium solution. The soft tissues of each foot were then counterstained with phosphomolybdic acid (PMA). The 2nd through 4th toe MTP joints of 12 feet were imaged with Nano-CT at 14-micron resolution. Images were then reconstructed for three-dimensional analysis of the plantar plate microvasculature and calculation of the vascular density along the length of the plantar plate. Results: A microvascular network extends from the surrounding soft tissues at the attachments of the plantar plate on both the metatarsal and proximal phalanx. The mid-substance of the plantar plate appears to be relatively hypovascular. Analysis of the vascular density along the length of the plantar plate demonstrated a consistent trend with increased vascular density at approximately the proximal 30% and distal 20% of the plantar plate (Figure 1). Conclusion: There is a vascular network extending from the surrounding soft tissues into approximately the proximal 30% and the distal 20% of the plantar plate. The hypovascular mid-portion of the plantar plate may play an important role in the underlying patho-anatomy and pathophysiology of this area. We believe our findings likely have significant clinical implications for the reparative potential of this region, and therefore the surgical procedures currently described to accomplish anatomic plantar plate repair.

Objective The purpose of this study was to determine if differences in Wiberg classification play a role in the ability of donor patellar osteochondral allografts to match the native patellar surface when treating osteochondral defects of the patellar apex. Design Twenty (10 Wiberg I and 10 Wiberg II/III) human patellae were designated as the recipient. Each recipient was size-matched to both a Wiberg I and a Wiberg II/III patellar donor. A 16-mm circular osteochondral “defect” was created on the central ridge of the recipient patella. The randomly ordered donor Wiberg I or Wiberg II/III plug was harvested from a homologous location and transplanted into the recipient. The recipient was then nano-CT (computed tomography) scanned, digitally reconstructed, registered to the initial nano-CT scan of the recipient patella, and processed to determine root mean squared circumferential step-off heights as well as surface height deviation. The process was then repeated for the other allograft plug. Results There was no significant difference in mean step-off height between matched and unmatched Wiberg plugs; however, there was a statistically significant difference in surface height deviation over the whole surface (0.50 mm and 0.64 mm respectively, P = 0.03). This difference of 0.14 mm is not felt to be clinically significant. Tibial width was correlated to patellar width ( r = 0.82) and patellar height ( r = 0.68). Conclusions For osteochondral allograft sizes up to 16 mm there appears to be no advantage to match donor and recipient patellar morphology. Further study is warranted to evaluate defects requiring larger graft sizes.

The horizontal mattress stitch may be the biomechanically superior configuration in plantar plate repairs.