Robert D. Santrock

Osteochondral lesions of the talus

Osteochondral lesions of the talus (OLT) are rare joint disorders. The talus is the third most common location of this disorder, following the knee and elbow joints. OLT represents 4% of all osteochondral lesions in the body. This article discusses the surgical treatment and postoperative rehabilitation of osteochondral lesions of the talus.

Cryopreserved human amniotic membrane injection for plantar fasciitis: a randomized, controlled, double-blind pilot study.

Background: Treatment options for plantar fasciitis have resulted in varied patient outcomes. The aim of this study was to compare a novel treatment, cryopreserved human amniotic membrane (c-hAM), to a traditional treatment, corticosteroid. Our hypothesis was that c-hAM would be safe and comparable to corticosteroids for plantar fasciitis in regard to patient outcomes. Methods: A randomized, controlled, double-blind, single-center pilot study was completed. Patients were randomized into one of 2 treatment groups: c-hAM or corticosteroid. Patients received an injection at their initial baseline visit with an option for a second injection at their first 6-week follow-up. Total follow-up was obtained for 12 weeks after the most recent injection. The primary outcome measurement was the Foot Health Status Questionnaire (FHSQ). The secondary outcome measurements were the Visual Analog Scale (VAS) and verbally reported percentage improvement. Data were analyzed between groups for the 2 different cohorts (1 injection versus 2 injections). Twenty-three patients had complete follow-up. Fourteen were randomized to receive corticosteroid and 9 were randomized to receive c-hAM. Results: Three patients in each group received second injections. With the numbers available, the majority of outcome measurements showed no statistical difference between groups. The corticosteroid did, however, have greater FHSQ shoe fit improvement (P = .0244) at 6 weeks, FHSQ general health improvement (P = .0132) at 6 weeks, and verbally reported improvement (P = .041) at 12 weeks in the one-injection cohort. Cryopreserved hAM had greater FHSQ foot pain improvement (P = .0113) at 18 weeks in the 2-injection cohort. Conclusion: Cryopreserved hAM injection may be safe and comparable to corticosteroid injection for treatment of plantar fasciitis. This is a pilot study and requires further investigation. Level of Evidence: Level I, prospective randomized trial.

A Historical Review of Common Bone Graft Materials in Foot and Ankle Surgery

Foot and ankle fusion is an important treatment for arthritis and deformities of the ankle and hindfoot. The literature has shown that there are improvements in fusion rates with the addition of bone graft and bone graft substitutes. Today autografts, specifically the iliac crest bone graft (ICBG), continue to be the gold standard despite significant donor site morbidity and nonunion rates, persisting around 10%. To address these drawbacks, bone graft substitutes have been developed. This article includes a historical review of the use, outcomes, and safety of autografts, allografts, and bone graft substitutes, such as ceramics, demineralized bone matrix, and platelet-derived growth factor.

Total Ankle Arthroplasty With Severe Preoperative Varus Deformity

Advancements in total ankle arthroplasty (TAA) over the past several decades have led to improved patient outcomes and implant survivorship. Despite these innovations, many implant manufacturers still consider a preoperative coronal plane deformity greater than 10° a relative contraindication to TAA. Without proper intraoperative alignment, these implants may experience abnormal wear and hardware failure. Correcting these deformities, often through the use of soft tissue procedures and/or osteotomies, not only increases the difficulty of a case, but also the intraoperative time and radiation exposure. The authors report a case in which a 54-year-old man with a severe right ankle varus deformity of 29° underwent successful TAA using the INBONE II Prophecy total ankle system (Wright Medical Technology, Inc, Memphis, Tennessee) and additional soft tissue reconstruction. Intraoperatively, the patients coronal deformity was corrected to 1.8°. At 8 months postoperatively, the patient ambulated without restriction and had substantial improvement in validated patient outcome scores, specifically the Academy of Orthopaedic Surgeons Foot and Ankle Module and the Short Form Health Survey-12 This unique report documents the first time that this particular implant, with an exclusive preoperative computed tomography-derived patient-specific guide, has been used effectively for a severe preoperative varus deformity greater than 20° without the need for an osteotomy. Future studies should be directed toward the prospective evaluation of different total ankle implant systems and their outcomes with severe coronal plane deformity, specifically computed tomography-derived patient-specific guided implants.

Accuracy and Reproducibility Using Patient-Specific Instrumentation in Total Ankle Arthroplasty

Background: Implant survivorship is dependent on accuracy of implantation and successful soft tissue balancing. System instrumentation for total ankle arthroplasty implantation has a key influence on surgeon accuracy and reproducibility. The purpose of this study was to determine the accuracy and reproducibility of implant position with patient-specific guides for total ankle arthroplasty across multiple surgeons at multiple facilities. Methods: This retrospective, multicenter study included 44 patients who received a total ankle implant (INBONE II Total Ankle System; Wright Medical Technology, Memphis, TN) using PROPHECY patient-specific guides from January 2012 to December 2014. Forty-four patients with an average age of 63.0 years underwent total ankle arthroplasty using this preoperative patient-specific system. Preoperative computed tomography (CT) scans were obtained to assess coronal plane deformity, assess mechanical and anatomic alignment, and build patient-specific guides that referenced bony anatomy. The mean preoperative coronal deformity was 4.6 ± 4.6 degrees (range, 14 degrees varus to 17 degrees valgus). The first postoperative weightbearing radiographs were used to measure coronal and sagittal alignment of the implant vs the anatomic axis of the tibia. Results: In 79.5% of patients, the postoperative implant position of the tibia corresponded to the preoperative plan of the tibia within 3 degrees of the intended target, within 4 degrees in 88.6% of patients, and within 5 degrees in 100% of patients. The tibial component coronal size was correctly predicted in 98% of cases, whereas the talar component was correctly predicted in 80% of cases. Conclusion: The use of patient-specific instrumentation for total ankle arthroplasty provided reliable alignment and reproducibility in the clinical situation similar to that shown in cadaveric testing. This study has shown that the preoperative patient-specific instrumentation provided for accuracy and reproducibility of ankle arthroplasty implantation in a cohort across multiple surgeons and facilities. Level of Evidence: Level III, retrospective comparative series.

Topical Review Use of Fetal Tissue in Foot and Ankle Surgery

Fetal tissues are well known for their therapeutic potential. They contain numerous growth factors, cytokines, and matrix components that promote regeneration of tissues while downregulating inflammation and scar formation. As a result, use of these treatments has expanded over the previous 20 years throughout various surgical specialties, including orthopaedics. With improved methods of sterilization, processing, and storage, surgeons need to be informed about the potential benefits of fetal tissue in foot and ankle surgery. The aim of this review is to provide a brief historical background, basic anatomy and physiology, and a current review of the literature in regard to chronic wounds, diabetic foot ulcerations, plantar fasciitis, tendon repair, adhesion prevention, nerve repair, and bone healing. Levels of Evidence: Level V: Expert Opinion

Ankle Fusion Stability: A Biomechanical Comparison of External Versus Internal Fixation

This biomechanical study compares bimalleolar external fixation to conventional crossed-screw construct in terms of stability and compression for ankle arthrodesis. The goals of the study were to determine which construct is more stable with bending and torsional forces, and to determine which construct achieves more compression.Fourth-generation bone composite tibia and talocalcaneal models were made to 50th percentile anatomic specifications. Fourteen ankle fusion constructs were created with bimalleolar external fixators and 14 with crossed-screw constructs. Ultimate bend, torque, and compression testing were completed on the external fixator and crossed-screw constructs using a multidirectional Materials Testing Machine (MTS Systems Corp, Eden Prairie, Minnesota). Ultimate bend testing revealed a statistically significant difference (P=.0022) with the mean peak load to failure for the external fixator constructs of 973.2 N compared to 612.5 N for the crossed-screw constructs. Ultimate torque testing revealed the mean peak torque to failure for the external fixator construct was 80.2 Nm and 28.1 Nm for the crossed-screw construct, also a statistically significant difference (P=.0001). The compression testing yielded no statistically significant difference (P=.9268) between the average failure force of the external fixator construct (81.6 kg) and the crossed-screw construct (81.2 kg).With increased stiffness in both bending and torsion and comparable compressive strengths, bimalleolar external fixation is an excellent option for tibiotalar ankle arthrodesis.

Effect of Dorsal Plate Positioning on Dorsiflexion Angle in Arthrodesis of the First Metatarsophalangeal Joint A Cadaveric Study

Background: The relationship between dorsal plate positioning and final dorsiflexion angle after first metatarsophalangeal (MTP) joint fusion has not been well established. The main purpose of this study was to investigate whether changes in dorsal plate positioning along the longitudinal axis affect fusion dorsiflexion angle, as excessive dorsiflexion angles can lead to poor clinical results. Methods: Ten cadaver foot specimens were randomly assigned to 2 groups for first MTP joint fusion: 1 group used a straight plate, and the other group used a 10-degree precontoured plate. After routine preparation, the plates were placed in an “ideal” position based on clinical and radiological examination. The plates were then moved proximally 3 mm and 6 mm from the initial site, with repeat imaging completed at each position. The radiological dorsiflexion angle was determined for each position, and the results were assessed. Results: Placement of both straight and precontoured plates at positions more proximal from the initial position led to significant increases in dorsiflexion angles (P = .04), although the percentage change was larger in the precontoured plate group (P = .01). While placement of the plate 3 mm proximal from the perceived “ideal” position did increase the dorsiflexion angle, the percentage of specimens with dorsiflexion angles in the suggested optimal range changed minimally. Positioning at 6 mm from the starting point, however, led to significantly increased dorsiflexion angles for both plates (P = .004). Conclusion: Positioning the dorsal plate at more proximal locations leads to increasing dorsiflexion angles. Precontoured plates are more likely to lead to excessive dorsiflexion compared with straight plates regardless of plate position. Clinical Relevance: Fusion at excessive dorsiflexion angles can be minimized with appropriate selection and proper positioning of the dorsal fusion plate along the longitudinal axis.

Complete encasement of the peroneal tendons by the peroneal tubercle.

The peroneal tubercle is an osseous structure on the lateral side of the calcaneus present in 90% of individuals. Hypertrophy of the peroneal tubercle resulting in stenosing peroneal tenosynovitis has been well described in the literature. Repair of this condition involves operative treatment to remove the hypertrophied peroneal tubercle and repair any resulting tendon pathology. The authors report a unique case of a hypertrophied peroneal tubercle with an associated tarsal coalition, resulting in complete bony encasement of the peroneal tendons. In this case, a 50-year-old white man presented with worsening bilateral foot and ankle pain for several years. On examination, he had fixed hindfoot varus and bilateral equinocavovarus feet. Magnetic resonance imaging and weight-bearing radiographs showed a calcaneonavicular coalition. Intraoperatively, the authors discovered complete bony encasement of the peroneal longus and brevis tendons. On examination, the peroneal longus and brevis were severely stenotic, with the peroneal brevis to the point of near laceration. This painful condition was repaired by takedown of the calcaneonavicular coalition, the peroneal tubercle was resected, and the peroneal tendons were freed from their bony encasement. Tenodesis of the peroneus brevis to longus was performed and the hindfoot varus was corrected with wedge osteotomy of the calcaneus. The patient reported excellent postoperative results. At 3 months postoperatively, he was pain-free and his calcaneal osteotomy was well healed. This case appears to be the first of its type to be reported in the literature. The details of the case are presented along with a review of the relevant literature.

Tarsal-Metatarsal Joint Arthrodesis

Arthrodesis of the first tarsometatarsal joint is a common procedure for patients with HAV deformity. The acceptance of this procedure has gone through an evolution over several generations. Traditional observations such as hypermobility and atavism are commonly cited as indications for TMTJ level of correction; however there is a wealth of new information which calls into question some of these ideas. The most striking new concept is the addition of the evaluation and management of the frontal plane of the deformity. In this chapter the authors will introduce new techniques performed through a single limited incision at the tarsometatarsal site that do not require traditional surgical dissection, capsular balancing, or osteotomy of the first metatarsal phalangeal joint and that facilitate fixation constructs tailored to allow the patient immediate protected weight bearing. The procedure and modifications discussed in this chapter are much different both in indications and technical execution than what has been historically described. Specifically, we do not use high intermetatarsal angle and hypermobility of the medial column as necessary indications for the procedure but use the anatomic apex of the deformity to choose the level of correction. Since the metatarsal is not deformed, we feel that correction at a proximal level to correct the position of the deviated metatarsal gives the most anatomic result as well as being a convenient location for triplane correction.