Eric J. Dein

Outcomes After Interpositional Arthroplasty of the First Metatarsophalangeal Joint

Background: For patients with hallux rigidus seeking a motion-sparing procedure, interposition arthroplasty is an alternative to fusion. The purpose of this study was to report patient outcomes after interpositional arthroplasty for hallux rigidus. Methods: All patients undergoing interpositional arthroplasty at our institution from 2001 to 2014 were identified and a retrospective chart review was performed. Follow-up was conducted through a telephone survey to obtain survivorship, satisfaction, and functional scores. Survivorship of the interpositional arthroplasty procedure was defined as no subsequent surgery on the hallux after the index procedure. Patients were excluded for incomplete records. Complications were recorded. From 2001 to 2014, 183 patients were identified. Of these, 14 were excluded for incomplete data, leaving 169 patients. Of these, 133 had an average follow-up of 62.2 months (range, 24.3 months to 151.2 months). Results: The overall failure rate was 3.8% (5/133). Patient-reported outcome was rated as excellent in 65.4% (87/133) or good in 24.1% (32/133) of patients and fair or poor in 10.5% (14/133) of patients. Of 133 patients, 101 (76%) were able to return to fashionable or regular footwear. The infection rate was 1.5% (2/133). Patient-reported cock-up deformity of the first metatarsophalangeal joint (MTPJ) occurred in 4.5% (6/133) of patients. In addition, 17.3% (23/133) of patients reported metatarsalgia of the second or third MTPJ at the time of final follow-up, and there was no significant difference between interposition types (P = .441). Conclusion: Interpositional arthroplasty for hallux rigidus was found to have excellent or good results in most patients at a mean follow-up of 62.2 months. Level of Evidence: Level IV, retrospective case series.

Influence of investigator experience on reliability of adult acquired flatfoot deformity measurements using weightbearing computed tomography

BACKGROUND Our purpose was to assess the reliability of measurements of adult-acquired flatfoot deformity (AAFD) taken by investigators of different levels of clinical experience using weightbearing computed tomography (WBCT). METHODS Nineteen AAFD patients underwent WBCT. Three investigators with different levels of clinical experience made AAFD measurements in axial, coronal, and sagittal planes. Intra- and interobserver reliability were assessed. Mean values for each measurement were compared between investigators. RESULTS After a training protocol, substantial to perfect intra- and interobserver reliability was observed for most measures, regardless of the investigators experience level. Significant differences between investigators were observed in 2 of 21 measured parameters: medial cuneiform-first metatarsal angle (P=0.003) and navicular-medial cuneiform angle (P=0.001). CONCLUSIONS AAFD radiographic measurements can be performed reliably by investigators with different levels of clinical experience using WBCT. LEVEL OF EVIDENCE Level II, prospective comparative study.

☆Diagnostic and therapeutic injections of the foot and ankle—An overview

Foot and ankle injections are useful diagnostic and therapeutic tools, particularly when the pain etiology is uncertain. A variety of foot and ankle injuries and pathologies, including degenerative joint disease, plantar fasciitis and different tendinopathies are amenable to injections. Understanding the foot and ankle anatomical landmarks, a thorough physical exam and knowledge of the different injection techniques is key for a successful approach to different pathologies. The objective of this study is to review the use of foot and ankle injections in the orthopaedic literature, present the readers with the senior authors experience and provide a comprehensive clinical guideline to the most common foot and ankle diagnostic and therapeutic injections.

Basic Science Research Trends in Orthopedic Surgery: An Analysis of the Top 100 Cited Articles

BackgroundMuch of current clinical orthopedics traces its origin to basic science investigation of cellular and biochemical pathways, tissue engineering, and biomechanics of bone and joint physiology in animal and cadaveric models.Questions/PurposesWe sought to describe research trends in highly cited basic science studies in orthopedics.MethodsBy searching Web of Science, we identified the 100 most cited basic science orthopedics articles and focused on author position and degree (PhD, MD, or MD/PhD), topic, type of study, country, institution, and citation trends.ResultsThese articles were published from 1970 to 2008 (citation range, 330 to 2111), with the majority from the USA (78). While there was no correlation between years since publication and total citations, more recent articles had higher citation rates. There were 38 unique first authors represented, with Caplan, Harris, Mankin, Noyes, and Warren as primary authors or co-authors of four articles each. Twelve journals published these 100 articles, with the majority in Journal of Bone and Joint Surgery (46) and Clinical Orthopaedics and Related Research (18). Frequent topics included biomechanics (31), healing/regeneration (21), and cellular/molecular biology (13). The Hospital for Special Surgery/Cornell University (10) published the most, followed by the Hospital for Joint Diseases/New York University (6), and University of Pittsburgh (6). No difference was observed in total citations and average citation rate by author degree. Eight articles were contributed from privately owned institutions or industry, with the rest from academic hospitals.ConclusionThis review may aid those seeking insight into landmark studies and future direction of basic science research in orthopedics.

Outcomes of flexor digitorum longus (FDL) tendon transfer in the treatment of Achilles tendon disorders

BACKGROUND In patients with chronic Achilles tendon disorders, Achilles tendon debridement can be supplemented with a tendon transfer, with the flexor hallucis longus tendon (FHL) transfer representing the most common used technique. Our study describes clinical and functional results of patients treated with flexor digitorum longus (FDL) tendon transfer in the treatment of patients with chronic Achilles tendon disorders. METHODS Retrospective study of prospectively collected data of thirteen patients (15 feet) that underwent FDL tendon transfer as part of the treatment of chronic Achilles tendon disorders. Preoperative and postoperative assessment included visual analogue score (VAS) for pain, SF-36 survey and lower extremity functional scale (LEFS). The average follow-up was 26.4 (range, 14-56) months. Patients were also assessed for ability to perform single leg heel rise test, muscle power for plantar flexion of the lesser toes, surgical scar condition and associated complications. RESULTS At final follow-up, we found significant postoperative improvement in VAS score (6.6 ± 2.99 vs 1.06 ± 1.43; p < .0001), SF-36 physical component summary (PCS) (28.20 ± 10.71 vs 45.04 ± 11.19; p < .0001) and LEFS (36.13 ± 20.49 vs 58.73 ± 18.19; p < .0001). Twelve patients (92%) could perform a single leg heel rise test in the operated extremity, although there was significant difference when comparing operated and uninvolved sides (4.86 ± 3.36 cm vs 7.18 ± 3.40 cm; p = .0002). One patient reported weakness for plantar flexion of the lesser toes, without balance or gait disturbances. Two patients (2 feet, 13.3%) had superficial infections and one patient (one foot, 6.6%) needed operative debridement for a deep infection. CONCLUSIONS FDL tendon transfer represent an operative alternative in the treatment of chronic Achilles tendon disorders. Our study showed good clinical outcomes with low complications and donor site morbidity. LEVEL OF EVIDENCE Observational study, case series - level IV.

Outcomes of Iliac Crest Bone Marrow Aspirate Injection for the Treatment of Recalcitrant Non- Insertional Achilles Tendinitis

Category: Sports Introduction/Purpose: Non-insertional Achilles tendinitis is a common cause of posterior ankle and heel pain in active and sedentary patients. Though the majority of patients respond to first-line non-operative management including activity modification, immobilization, orthotics, and physical therapy with tendon stretching, there is no consensus for patients that fail these treatments. We evaluate the role of iliac crest bone marrow aspirate concentrate (BMAC) as a safe and effective treatment option for recalcitrant cases. Methods: A retrospective chart review was conducted of patients with greater than 12 months of non-insertional Achilles tendinitis symptoms despite appropriate conservative treatment. Each patient had BMA harvested from the iliac crest, concentrated by centrifugation, and then injected into the Achilles tendon. Symptoms were assessed using the Visual Analogue Scale (VAS) pain score, collected at the preoperative office visit and at 6 weeks, 12 weeks, and 24 weeks after the procedure. Co- morbidities, concurrent procedures, and complications were also recorded. Results: A total of 21 patients (22 feet) were treated with iliac crest BMA concentrate injections. Preoperatively, the average VAS pain score was 6.8 (SD 2.0). Postoperatively, the average VAS was 4.0 (SD 2.5) at 6 weeks, 2.7 (SD 2.1) at 12 weeks, and 2.2 (SD 2.1) at 24 weeks. At 24 weeks postoperatively, there was a statistically significant decrease VAS score from baseline (p < 0.001), with a mean decrease by 4.6 (SD 3.1). There were no adverse effects reported at the surgical site or donor site morbidity at the iliac crest such as wound infection, hematoma, or persistent pain. Conclusion: Iliac crest BMAC appears to be a safe, effective, and potentially lasting treatment option for patients with intractable, non-insertional Achilles tendinitis. Patients demonstrated a statistically significant decrease in VAS pain score postoperatively with no complications at the donor or injection site.

Interobsever Variability of Measurements for Flatfoot Deformity Using High Resolution Weightbearing Cone-Beam CT Examination According to Reader Experience

Category: Other Introduction/Purpose: To evaluate interobserver reliability among readers of different clinical experience by applying measurements for adult acquired flatfoot deformity (AAFD) using high-resolution three-dimensional (3D) weightbearing (WB) cone-beam CT (CBCT) examination. Methods: In this IRB approved study, 20 patients with flexible AAFD [12 male, 8 female; mean age 54.2 (20-88) years] were scanned with standing (weightbearing) CTs. Two blinded observers, a medical student and a foot/ankle surgeon, applied validated AAFD measurements in sagittal, coronal, and axial planes using predefined anatomical landmarks. Interobserver reliability was calculated using Pearson correlation. Results: There was significant interobserver agreement with high correlation for the following measurements(p < 0.0001): distances between medial cuneiform to-floor (r=0.981) and to-skin (r=0.986), navicular to-floor (0.992) and to-skin (r=0.900); cuboid to-floor (r=0.975) and to-skin (r=0.978), and calcaneus-to-fibula (r=0.808); calcaneal inclination angle (r=0.795); forefoot arch angle (r=0.983); and subtalar horizontal angles at 25%, 50%, and 75% of the anteroposterior joint length (r=0.784, 0.891, 0.809). Significant agreement with moderate correlation was additionally demonstrated for talar-first metatarsal angle (r=0.553, p < 0.014), medial cuneiform-first metatarsal angle (r=0.668, p < 0.001), and navicular-cuneiform angle (r=0.746, p < 0.0002). Level of training did not influence the reliability of any measurements except medial cuneiform-first metatarsal angle (specialist: 8.83°; student: 1.61°; p < 0.01). Statistically insignificant difference between readers (p>0.05) was noted in mean talar-first metatarsal and subtalar horizontal angles. Conclusion: While literature describes large variability for AAFD measurements from plain radiographs among readers of varying medical experience, 3D WB CBCT can yield similar measurements using predefined planes with high reliability, independent of reader experience.

Flexible Adult Acquired Flatfoot Deformity: Comparison Between Weightbearing and Nonweightbearing Cone-Beam CT Examinations

Category: Other Introduction/Purpose: Adult acquired flatfoot deformity (AAFD) is a biomechanical derangement involving the three- dimensional (3D) midfoot and hindfoot osseous complex, which can be challenging to optimally characterize using conventional two-dimensional (2D) plain radiographs. Weightbearing (WB) Cone-Beam CT (CBCT) can better demonstrate the deformity of the 3D structures during WB. Therefore, we compared validated AAFD measurements between non-weightbearing (NWB) and WB CBCT images. Methods: In this prospective, IRB approved study, 20 patients were included, 12 males and 8 females, mean age of 54.21 (20-88) years, with clinical diagnosis of flexible AAFD. Subjects were scanned with standing (WB) and seated (NWB) CBCTs. WB and NWB CBCT images were assessed with traditional flatfoot measurements obtained at sagittal, coronal, and axial planes using predefined anatomical landmarks, by two independent observers. Interobserver reliability was calculated using Pearson correlation. Results: The measurements in patients with AAFD differed significantly between WB and NWB CBCT images. Specifically, WB images showed, when compared to NWB, decreased forefoot arch angle (mean difference: 9.91°, p < 0.0001), increased talus-first metatarsal angle (10.59°, p < 0.0001), increased navicular-medial cuneiform angle (13.89°, p < 0.0001), decreased navicular-floor (coronal 14.05mm/sagittal 14.91mm, p < 0.0001) and navicular-skin distances (coronal 5.87mm/sagittal 8.25mm, p < 0.0001), decreased medial cuneiform-floor (coronal 10.79mm/sagittal 11.07mm, p < 0.0001) and medial cuneiform-skin distances (coronal 4.45mm/sagittal 5.78mm, p < 0.0001), and decreased cuboid-floor (5.78mm, p < 0.0001) and cuboid-skin distances in the sagittal plane (4.60mm, p < 0.0001). Interobserver reliability was good to excellent (0.610-0.991). Conclusion: Traditional adult acquired flatfoot deformity radiographic measurements are obtainable using high resolution 3D WB CBCT imaging, and can help characterize the biomechanical derangements during weightbearing in subjects with flexible AAFD.

Long-Term Outcome Following Interpositional Arthroplasty of the First Metatarsophalangeal Joint

Category: Midfoot/Forefoot Introduction/Purpose: Surgical treatment for osteoarthritis of the first metatarsophalangeal joint (MTPJ) includes cheilectomy or fusion for advanced arthritis. In addition, procedures to preserve or restore motion have demonstrated promising short-term results. Currently, no studies have described long-term results following interpositional arthroplasty. Our institution has performed interpositional arthroplasty with autograft (joint capsule/extensor hallucis brevis) or allograft (dermal matrix) with anecdotal success for over 15 years. The purpose of this study is to report long-term outcomes following interpositional arthroplasty. Methods: All patients undergoing interpositional arthroplasty at our institution from 2000-2015 were identified and a retrospective chart review was performed. Long-term follow-up was conducted through a telephone survey to obtain survivorship, satisfaction, and functional scores. Average follow-up was 89.1 months (range, 6 to 179 months). Survivorship of the interpositional arthroplasty procedure was defined as no subsequent surgery on the hallux after the index procedure. Results: From 2000-2015, 292 interpositional arthroplasties were performed at our institution. The overall failure rate was 1.7 % (5/292), which included patients requiring revision surgery (2 patients) or subsequent fusion (3 patients). Autograft interpositional arthroplasty had a failure rate of 2.1% (2/94) and allograft interposition was 1.5% (3/198). Failure and reoperation occurred at an average of 11 months from the index procedure (range, 6-17 months). 88.7% of patients rated their overall satisfaction as excellent or good. Average preoperative VAS score was 8.2 ± 1.5 (range, 6 to 10) and 2.1 ± 1.6 (range, 0 to 7) at latest follow-up, and (79.1%) patients reported tolerance to fashionable shoes. There were no major wound complications. The most common complications were metatarsalgia (8.6%) and cock-up deformity (5.7%). Conclusion: Interpositional arthroplasty demonstrated excellent long-term survivorship and high patient satisfaction at long-term follow-up.

Tendinopathy Induced by Serial Low-Dose Collagenase Injections A Novel Experimental Animal Model in the Achilles Tendon of Rabbits

Category: Basic Sciences/Biologics Introduction/Purpose: Numerous studies, as evident in literature, have attempted to develop an induced Achilles tendinopathy animal model. The most common models include collagenase injections and mechanical overload of the tendon, but both are controversial. The mechanical overload model creates a chronically induced tendinopathy and is time intensive. In addition, once the stimulus is removed the tissue changes often heal. The collagenase injection model is quicker, rarely evolve to healing but frequently results in an early acute tendon reaction. The primary objective of this study is to compare biomechanical and histological findings between two collagenase induced Achilles tendinopathy protocols. The hypothesis is that consecutive low-dose collagenase injections will result in progressive and long-lasting tendinopathy findings as compared to the traditional single high-dose injection. Methods: In this IRB approved study, the population was composed of forty-eight (n=48) New Zealand breed rabbits. Forty-two (n=42) rabbits were randomly divided into two groups (n=21). The first group, which served as the control, had both Achilles tendons injected by a single dose (0.3 mg) of A1 collagenase (Sigma-Aldrich©), as described in literature. The second experimental group had three low-dose injections (0.10 mg) with 2 weeks between each injection. Another six animals (n=6) were also randomized into two groups (n=3) receiving one-dose versus 3 injections of saline solution with 2 weeks between each injection. The animals were euthanized after 10, 12 and 16 weeks. Histological and biomechanic analysis of the Achilles tendons were carried out using a dynamic mechanical testing machine (Electropuls®, model E10000, Instron®). Mechanical strength and histological scores of tendinopathy (Bonar scoring system) were compared among the groups at each time-point. Results: After 16 weeks, all biomechanical and histological parameters analysed showed consistent differences between the groups (p < 0.05), with more pronounced and long-lasting tendinopathy findings in the Achilles tendon of the experimental group (serial collagenase injections), when compared to the control groups (single collagenase dose and single/multiple saline injections). The mean Bonar sum-score of tendons after 16 weeks in the experimental group was greater than the mean histologic score of control tendons (8.53 ± 1.52 versus 1.1 ± 0.83 in saline group and 5.2 ± 1.12 in single dose group). No statistically significant differences were found between the different collagenase injection groups at weeks 10 and 12. Conclusion: The protocol of three consecutive low-dose collagenase injections has shown biomechanical and histological findings compatible with progressive and long-lasting tendinopathy as compared to single high-dose injection. This protocol represents a feasible and effective animal model of induced Achilles tendinopathy.