bluuebunny/crossref_metadata_2025_split huggingface dataset:
STAR™ Ankle
Authors: Palanca Ariel , Mann Roger A. 
Published: October 2016

Category: Ankle Arthritis. Introduction/Purpose: Over the past decade, total ankle arthroplasty (TAA) has become a mainstay in the treatment of end stage ankle arthritis. Currently in its fourth generation, the Scandanavian Total Ankle Replacement (STAR™) is the only 3-piece mobile bearing design available in the United States. Current studies show 89-94% survivorship of the STAR™ at 9-12 years follow-up. We report patient outcomes at a minimum of 15 years. Methods: 24 patients from the initial U.S. STAR™ FDA trial who had undergone no metal revision at 10 year follow-up were available for participation. Radiographic examinations were performed for all patients. Changes in prosthetic position, coronal and sagittal plane alignment, osteolysis, adjacent joint arthritis, and heterotopic ossification were documented. Clinical examinations were performed for 14 patients. Clinical findings, AOFAS ankle/hindfoot scores and SF-36 scores were recorded. All secondary procedures and complications were noted. Implant failure was defined as revision or explant of either the tibial or talar component. Results: 87.5% (21/24) of participants had metal survivorship at a minimum of 15 years. Two patients required revision surgery for aseptic loosening and one required a tibiotalocalcaneal fusion for a progressive coronal plane deformity. Of the 21 patients with metal survivorship, the AOFAS ankle/hindfoot rating scale improved from an average of 39.6 points preoperatively, to an average of 71.6 points at latest follow up (range 42-89). The average SF-36 score was 49.0. Postoperative range of motion averaged 17 degrees (range 5-30°). Adjacent joint arthritis was seen radiographically in 5 patients (23.8%), one which required a subtalar fusion. Two patients required exchange for a broken polyethylene spacer. 11/21 (52.4%) of patients required an additional surgical procedure, 3 of whom required two additional procedures. Average time to subsequent procedure was 10.2 years. Conclusion: Our data shows that if the STAR™ ankle has survived for 10 years, it will likely survive for 15 years. On the whole, patients reported good subjective outcomes, maintaining a near 30 point improvement in AOFAS scores. Revisions after 10 years were seen for aseptic loosening and coronal plane deformity. Patients should be counseled that it is common to have a subsequent procedure, which averaged 10 years postoperative from our experience. Further advancement in instrumentation, polyethylene wear characteristics, and revision implants will likely be the next stage in the advancement of TAA.
What Variables Influence Final Range of Motion Following Total Ankle Arthroplasty
Authors: Lee Wei Ting , Myerson Mark S. , Grosshans Kevin T. 
Published: October 2016

Category: Ankle Arthritis Introduction/Purpose: While studies have demonstrated a predictable incremental increase in the range of motion (ROM) following total ankle arthroplasty (TAA) it remains unclear what variables affect the post-operative ROM. This study was undertaken to further investigate this question with the goal of providing guidance for patients and surgeons deciding between TAA and arthrodesis. Methods: This is a prospective review of 223 consecutive patients who underwent primary TAA using a single prosthesis performed between 2010-2013 for painful ankle arthritis that failed conservative therapy. Weight bearing flexion and extension X- rays were obtained preoperatively and again at 1 year following surgery. The patients were compared for demographics, type of arthritis, preoperative malalignment, prior trauma, obesity, medical co-morbidities, and the effect of concurrent surgery on post operative ankle ROM. Results: 191 patients had adequate follow-up and met all the inclusion criteria. The preoperative diagnosis, hindfoot or ankle varus or valgus, and concurrent percutaneous tendon Achilles lengthening (TAL) procedures were positive predictors of greater improvement in ankle ROM after TAA. Patients with valgus ankle malalignment had better post TAA DF, PF and total ankle range of motion compared to those in varus (P < 0.05). Percutaneous tendon Achilles lengthening (TAL) improved the DF, but not the PF (P < 0.05). Patients with primary ankle osteoarthritis (n=105) had the best improvement in ROM with an average gain of 3.39° in dorsiflexion (DF), 2.47° in plantar flexion (PF) and 5.84° in total ankle ROM (P < 0.05). An analysis of this subgroup demonstrated greater gain in ankle ROM in patients with lower preoperative ROM compared to those with higher preoperative ankle ROM(P < 0.01). Conclusion: Our results indicated primary ankle OA, preoperative ankle valgus malalignment and intraoperative TAL are significant factors in predicting increased ankle ROM after TAA. Ultimately, ankle motion is a function of the extent of arthritis, fibrosis and the surrounding soft tissue envelope. While TAA restores the function of the joint, it may not adequately correct periarticular fibrosis. Early weight bearing and physical therapy may alleviate postoperative stiffness, and increase the post operative gain in ROM. Further study is underway to determine the effect of early weight bearing and initiation of physical therapy on the ROM following TAA.
A Retrospective Study
Authors: Smith Kenneth S. , Jones Caleb W. , Elattar Osama , Shah Ashish 
Published: October 2016

Category: Ankle Introduction/Purpose: Tibiotalocalcaneal arthrodesis (TTCA) is a salvage procedure for end-stage pathology of the tibiotalar and subtalar joints including primary arthritis, severe deformity, failed total ankle arthroplasty, failed ankle arthrodesis with subsequent subtalar arthritis, talus avascular necrosis and Charcot arthropathy. Although many different fixation techniques of TTCA have been proposed, there is still no consensus gold standard fixation strategy. The various options include plate and screw constructs, intramedullary nails and external fixator systems. The purpose of this study is to report our experience with rigid fixation using a commercially available 4.5 mm locking plate for TTCA. Methods: We retrospectively reviewed the clinical charts and radiographs of 17 patients who underwent TTCA during the time period of 2012-2014. We used a lateral surgical approach with fibular osteotomy and a 4.5 mm Smith and Nephew™ PERI-LOC ankle fusion plate. Two senior foot and ankle surgeons at our institution performed all surgeries. The main outcomes were postoperative fusion rate and complication rate. Results: Of the 17 patients, 9 were male and 8 were female with a mean age of 53. 29% of patients had diabetes mellitus and 69% were either current or former smokers. The average BMI was 32.9. The average follow up was 17.7 months. The nonunion rate in our patient series was 76%. Nonunion was defined as no radiographic evidence of fusion at 6 months post-surgery. This failure rate is very high in comparison to historical data of nonunion rates in TTCA, which are often reported to be 7-26%. Only four out of 17 patients had a successful arthrodesis using this locked plate construct. Complications included nonunion, hardware failure (with screws and/or plate fracture), deep infection (35% of patients), and pseudoarthrosis. Conclusion: Too rigid of fixation with thick stainless steel plates and locking screw constructs can lead to failure in tibiotalocalcaneal arthrodesis. Increased nonunion rates due to overly rigid fixation has been demonstrated in many other contexts but never in the foot and ankle literature.
Potential Contribution of Abnormal Talar Dome Lateral-Wall Geometry to Development of Ankle Osteoarthritis
Authors: Tochigi Yuki , Ogawa Masato , Kakihana Masataka , Ozeki Satoru 
Published: October 2016

Category: Ankle Arthritis Introduction/Purpose: Abnormal tibial plafond geometry, varus deformity and insufficient talar anterior coverage in particular, is well recognized as congenital factors predisposing ankles to osteoarthritis (OA), both primarily and after lateral ligament injury. Presumably, abnormal geometry of the gutter articulations (for the medial and lateral malleoli) also increases a risk of ankle OA, though this concept has not been well addressed to date. The talar side-wall surfaces, which appears to be less affected by degenerative deformity in ankle OA, may leave the congenital characteristics of the gutter articulation geometry. To identify a type of ankles at higher risk of OA development in this context, the present study explored characteristics of the talar side-wall geometry in OA ankles. Methods: Clinical CT images, from 21 moderate to advanced OA ankles without critical preceding pathologies and from 29 age- matched non-OA ankles, were subjected to 3-D morphometric evaluation of the talar dome side-wall geometry. Using a DICOM viewer (AquariusNET®, TeraRecon, Foster City, CA, USA), a local coordinate system for each ankle was manually established using talar landmarks. Then, on a transverse section at 3-5 mm distal to the superior aspect of the talar trochlea, the angle between the medial and lateral side-wall tangential lines (regressed from five cortical surface reference points for each) was measured as the “anterior opening angle.” Similarly, the “inferior opening angle” was measured on a mid-coronal section. Differences between groups were statistically tested using a t-test, with the significant level of p set at 0.05. Results: The anterior opening angle was significantly larger (p = 0.006) in the OA ankles (mean +/- SD: 11.9 +/- 6.0 degrees) than in the non-OA ankles (8.5 +/- 3.2). The inferior opening angle was also significantly larger (p = 0.007) in the OA ankles (30.7 +/- 11.1) than in the non-OA ankles (25.2 +/- 5.5). Defining the range of mean +/- 2SD as “normal” (Figure), 13 out of 21 (62%) OA ankles had both or either abnormally large anterior and/or inferior opening of the talar side-wall surfaces. Conclusion: Anterior and inferior opening trapezoidal shapes are common characteristic of the talar dome geometry. It is also well recognized that the degrees of opening substantially vary across individuals. The present study documented frequent occurrence of excessive anterior and/or inferior opening in OA ankles. Assuming that these abnormalities are inherent characteristics rather than results of degeneration, excessive anterior and inferior openings of the talar dome side-walls could be pathogenetical factors that increase a risk of ankle OA. Clinically, when ankles with excessive anterior and/or inferior opening talar dome side-walls would have ligament insufficiency, surgical repair or reconstruction should be considered to minimize a risk of future OA development.
Male Hallux Valgus Corrected by Translational Osteotomy of First Metatarsal
Authors: Dixon Alexis E. , Myer David , Elkins Jennifer E. , Brodsky James W. 
Published: October 2016

Category: Bunion Introduction/Purpose: Male hallux valgus (HV) is less common and more severe than in females, and has been reported to be associated with higher Distal Metaphyseal Articular Angle (DMAA). Although valgus-producing osteotomies should increase DMAA, this has not been documented. This study evaluated the results of a translational osteotomy that counter-rotates the distal metatarsal articular surface in a varus direction to re-align the articular surface, and correct the DMAA. Methods: Prospectively collected pre-op and post-op data on 26 males with HV were retrospectively reviewed, at a minimum one-year followup. Radiographic data included hallux valgus (HVA), first-second intermetatarsal (IMA) angles, DMAA, medial sesamoid position (MSP), and first MTPJ congruence. Clinical outcomes included Visual Analog Score (VAS), SF-36, and AOFAS forefoot score. MTP range of motion (ROM) was measured. Preoperative radiographic and clinical data were compared to previously published cohort of female patients for the same measures. Paired t-tests compared clinical and radiographic outcomes pre- and postoperatively. Bowker’s Test was used to compare the rate of joint congruence. An alpha of 0.05 was considered significant. Student t-test and Fisher’s Exact Test were for comparison between males and females. Mean age of males with HV was 53.8 (SD=17.7), mean follow-up was 1.68 years. Results: Mean radiographic improvement: HVA 36.5º to 15.3º (P=0.0001); IMA 15.9 to 8.1 (P=0.0001); DMAA 13.3º to 6.4º (P=0.0003); MSP 2.8 to 1.2 (P=0.0001); congruence 4/26 to 22/26 (P=0.0001). Mean clinical improvements: VAS 5.7 to 1.0 (P=0.0001); AOFAS 49.6 to 84.7 (P=0.0001); SF36-P 44.7 to 51.2 (P=0.0004). MTP dorsiflexion decreased 58.3º to 51.8º (P=0.0276); plantarflexion 5.8º to 3.0º (P=0.0217). Higher mean preoperative angles in males versus females: HVA 35.8º versus 29º (P=0.0016); IMA 15.9º versus 13.0º, (P=0.0002), MSP 2.7 versus 2.5 (P=0.2012). No difference in DMAA, 13.6 versus 16.4 (P=0.2551). Congruence in males lower (5/27 versus 22/40, P=0.0048). No difference in VAS (5.6 versus 6.3, P=0.1767), AOFAS (50 versus 47.9, P=0.5085), SF-36p (45.1 versus 42.4, P=0.2656), dorsiflexion (57.9º versus 49.4º, P=0.0728), plantarflexion (5.8º versus 4.8º, P=0.7204). Conclusion: Prior studies reported the results of mixes of surgical procedures. This is the first large series of adult male HV treated with a single procedure, and the first using this counter-rotational modification of the Scarf osteotomy. The modified Scarf osteotomy combines translation varus counter-rotation to direct the articular surface more medially, explaining decreased DMAA, and with excellent radiographic and clinical outcomes. We demonstrate excellent radiographic and clinical outcomes in a large group of male HV treated with translational osteotomies.
Sparing the Naviculocuneiform Joint during Medial Column Stabilization for Rigid Flatfoot Deformity
Authors: Huh Jeannie , Lampley Alexander J. , Gross Christopher E. , Adams Samuel B. , Nunley James A. , Easley Mark E. 
Published: October 2016

Category: Midfoot/Forefoot Introduction/Purpose: Combined arthrodesis of the talonavicular (TN) and 1st tarsometatarsal (TMT) joints is a treatment option for the patient with both a rigid flatfoot and hallux valgus deformity or 1st TMT joint arthritis. In these cases, the naviculocuneiform (NC) joint is spared, as long as no evidence of joint collapse or instability is present. The purpose of this study was to assess the effect of this medial column stabilization construct on the spared NC joint over time and its ability to improve the radiographic parameters in the flatfoot deformity. Methods: Patients who underwent concomitant TN and 1st TMT joint arthrodesis, while sparing the NC joint, in the setting of a rigid flatfoot deformity, between January 2006 and December 2014, were identified. The medical records, including preoperative and postoperative radiographs were retrospectively reviewed. Outcomes included radiographic correction gained by surgery (AP and lateral talo-first metatarsal angles), union rate, complications, and need for subsequent surgery. Specific radiographic attention was paid to development of subsequent collapse and/or arthritis at the NC joint at the time of final follow-up. Results: 21 consecutive combined TN and 1st TMT joint arthrodeses were performed. Average age at time of surgery was 61 (range, 23-82) years. 17 patients had a mean follow-up of 35 (range, 12-88) months. Union was achieved at both arthrodesis sites in 16/17 patients (94.1%). One patient (5.9%) had a nonunion at the TN joint, requiring revision arthrodesis. The mean lateral talo- first metatarsal angle correction was 24.5 (range, 12-36) degrees. The mean AP talo-first metatarsal angle correction was 11.6 (range, 0-33) degrees. One patient (5.9%) developed NC joint collapse and underwent subsequent arthrodesis at that level. There was radiographic evidence of NC joint arthritis to varying degrees in all cases by the time of final follow-up, however, none were symptomatic to warrant arthrodesis. Conclusion: Simultaneous arthrodesis of the TN and 1st TMT joints, while sparing the NC joint, is a reliable treatment in the carefully selected patient who presents with both a rigid flatfoot and hallux valgus deformity or 1st TMT joint arthritis. Good results in terms of union rate and radiographic correction, as well as a low complication rate were found in this study. Subsequent joint collapse and symptomatic arthritis at the spared NC joint was rare. Longer term follow-up and inclusion of functional outcomes are warranted in future studies on this topic.
Surgical Anatomy of a Novel Medial Gastrocnemius Recession versus the Proximal Medial Gastrocnemius Recession
Authors: Oh Irvin C. , DiGiovanni Benedict F. , Kaplan Nathan B. , Fowler Xavier 
Published: October 2016

Category: Hindfoot Introduction/Purpose: Isolated gastrocnemius contracture (IGC) is associated with various foot and ankle pathologies. To address the problem of IGC, a number of gastrocnemius lengthening procedures have been described. Decreased power and endurance with plantar flexion activities have been reported in patients after the Strayer procedure. Although proximal medial gastrocnemius recession (PMGR) has shown to be an effective surgical treatment for IGC, it poses risks to various anatomic structures around the knee joint and requires the patient to be positioned prone. The aim of this study was to describe an anatomic basis for a novel medial gastrocnemius recession (MGR) at the mid-level of the gastrocnemius muscle and to investigate the anatomical structures at risk in comparison to PMGR. Methods: Ten fresh frozen cadaveric lower leg specimens were employed for the study. The standard PMGR and the novel MGR were performed on each specimen. For the MGR procedure, we made a 2 cm incision over the mid-level of the medial gastrocnemius muscle region and performed complete release of the medial gastroncnemius fascia. After completion of the two procedures, complete dissection was performed to investigate the distances between surgically released fascia margins and surrounding anatomic structures including the greater saphenous vein, small saphenous vein, saphenous nerve, medial sural cutaneous nerve, semimembranosus tendon, tibial nerve and popliteal artery. These distances were recorded and compared statistically. Results: Proximities of anatomic structures to surgically released gastrocnemius fascia were significantly different between the two techniques. Major neurovascular structures were closer to the surgical margin than anticipated and at greater risk with the PMGR. In particular, popliteal artery (average distance 6.62 mm) and the tibial nerve (8.04 mm) were in close proximity with the PMGR margin, whereas these structures were deeply embedded and farther away from the MGR margin. For the PMGR, the semimembranosus tendon (average distance of 4.16 mm), small saphenous vein (6.71 mm), medial sural cutaneous nerve (3.66 mm), were also in close proximity to the surgical margin. For the MGR, the structures closer to the surgical margin and thus at greater risk of injury were the greater saphenous vein (12.22 mm) and saphenous nerve (11.87 mm). Conclusion: Medial gastrocnemius recession (MGR) at the central level of the gastrocnemius muscle may be an attractive surgical option and method when addressing IGC associated with various foot and ankle disorders. It can easily be performed in either the supine or prone position and may allow for less risk of injury to major surrounding neurovascular structures than a more proximal release. The biomechanical and clinical efficacies of the proposed MGR warrant further investigation.
Morphology of the Hindfoot in Pes Cavus
Authors: Schmid Timo , Roth Manuel , Schumann Steffen , Krause Fabian 
Published: October 2016

Category: Hindfoot Introduction/Purpose: The characteristic cavovarus deformity includes an adducted forefoot, an elevated longitudinal arch, and a hindfoot varus. However, little is known whether the deformity simply reflects pathologic joint orientations caused by muscular imbalance or whether it is rather provoked by alterations of the bony morphology. The purpose of the study was to further evaluate the source of the neurogenic and idiopathic cavovarus deformity by weightbearing 3D CT. Methods: Weightbearing CT scans of 12 patients with neurogenic and 17 patients with idiopathic cavovarus deformity were compared to neutrally aligned feet of 19 volunteers. AMIRA® software was employed to segment individual bones and to generate a 3D model. The 3D joint surface vector (JSV) with its 3 components in the transverse, coronal, and sagittal plane was computed for each joint surface of the talus, calcaneus, navicular and distal tibia. The positions of the ankle, subtalar and talonavicular joints were compared among the groups using the JSVs of the corresponding joint surfaces. The relative orientations of the joint surfaces on each individual bone were compared using the JSVs of head, trochlea and posterior facet for the talus; posterior facet and anterior process for the calcaneus; and anterior and posterior surfaces for the navicular. ANOVA tests were used for statistical analyses. Only statistically significant results (p < 0.05) are reported in this abstract. Results: Regarding the joint orientations, the talonavicular joint revealed 9° more adduction in idiopathic cavovarus feet than in control feet. In the neurogenic and idiopathic cavovarus groups the talar head exposed 34° and 20°, respectively, more adduction relative to the trochlea and 19° and 25°, respectively, more adduction relative to the subtalar joint than in the control group. Neurogenic cavovarus feet had 11° and 16°, respectively, more talar head internal rotation in the coronal plane relative to the subtalar joint than idiopathic cavovarus and control feet. In the idiopathic cavovarus group the anterior calcaneal process showed 9° more adduction relative to the posterior calcaneal facet and the anterior navicular surface had 8° more plantar flexion relative to the posterior navicular surface than in the control group. Conclusion: Alterations of bone morphology were more pronounced in the neurogenic group and mainly related to the talar head, whereas the idiopathic group also exposed changes of calcaneal and navicular bone morphology and talonavicular joint orientation. This indicates that the idiopathic cavovarus deformity is more induced by pathologic joint orientations due to muscular imbalance (or forefoot-driven) than the neurogenic deformity. Thus, neurogenic more so than idiopathic cavovarus deformities entail bone morphology changes of the hindfoot (hindfoot-driven), too. Therefore, to fully address the deformity corrective osteotomies, i.e. talar head realignment for neurogenic cavovarus feet, should be taken into consideration.