Parallax and Distortion in Fluoroscopy Units.

BACKGROUND: Parallax is an imaging phenomenon where an object appears to be at different positions when viewed from different angles. Distortion can occur secondary to internal fluoroscopic, or external environmental, factors. Fluoroscopy is a vital tool to assist surgeons intraoperatively. However, parallax and distortion can lead to inaccuracy, potentially leading to incorrect surgical decisions. The purpose of this study was to investigate the prevalence of parallax/distortion in large fluoroscopy units at a level-1 trauma center. METHODS: Two types of C-arm models were evaluated, including (1) round image intensifiers, and (2) flat plate detectors (FPD). A square plexiglass grid with embedded wire at ½-in intervals was created, with a round metal washer secured centrally. The grid was placed 16 in from the image intensifier. A metal ball bearing (BB) was secured to the center of the x-ray tube. Fluoroscopic images were obtained until the BB and washer were "center-center." A straight blade served as a fiducial marker to ensure there was no off-axis angulation. Standard anterior-posterior and lateral views were obtained. External factors were considered, tested, and limited. Images were printed and the patterns of parallax/distortion were identified. RESULTS: All 11/11 (100%) of fluoroscopy units had some degree of parallax and/or distortion. We noted 3 different patterns, including sigmoidal, converging, and diverging. The FPD units had less apparent distortion overall; however, two-thirds (66%) were off-axis in the x- and y-axes in relation to the fiducial marker. CONCLUSION: All fluoroscopy units had varying degrees and patterns of parallax/distortion. We noted less overall distortion in FPDs. However, some of these units may produce images that are off-axis. This research has important implications for improving the accuracy of intraoperative fluoroscopy. Musculoskeletal surgeons should understand the limitations of fluoroscopy and how to combat parallax distortion to improve surgical outcomes and reduce patient morbidity. LEVEL OF EVIDENCE: Level V.

Functional Outcomes and Complications Associated With Total Talus Arthroplasty: A Systematic Review.

Total talus arthroplasty (TTA) is a motion sparing procedure which can be utilized in specific and unique cases of talar necrosis and/or collapse. Literature on TTA is limited and predominantly composed of case studies or case reports. The purpose of this publication is to compile a systematic review of functional outcomes and complications associated with TTA. A search of current literature on TTA with >1-year follow-up was performed. Studies that described talar body implants or talonavicular implants were excluded. Twenty articles met inclusion criteria, which represented 161 TTAs. The average follow-up was 37.35 months (9-60 months). The indication for a TTA was predominately avascular necrosis of the talus, comprising 75.78% (122/161) of cases. The overall complication rate was 9.32% (15/161), with wound healing complications (5/161), replacement or implantation of a tibial component (4/161), and medial malleolus fracture (3/161) being the most common. One patient required proximal amputation due to residual pain and deformity. Functionally, American Orthopedic Foot and Ankle Score increased from 27.93 preoperative to 81.99 postoperative and Japanese Society for Surgery of the Foot Score increased from 43.2 preoperative to 89.34 postoperative. Visual analog scale pain score decreased from 6.44 to 2.60. Total ankle range of motion increased from 36.60° to 46.74°. Ankle plantarflexion increased by 3.45° and ankle dorsiflexion increased by 6.69°. Overall, available literature on TTA appears to be in favor of the procedure when indicated.Levels of Evidence: 4.

Use of Small Joint Arthroscopy for Diagnosis and Treatment of a First Metatarsal Head Osteochondral Defect: A Case Report.

CASE: A case of a painful first metatarsophalangeal joint in a 28-year-old woman is reported. Clinical examination and imaging were suspicious for osteochondral lesion of the first metatarsal head. A 1.9-mm arthroscope was used for diagnosis and treatment of an osteochondral defect with microfracture and dehydrated, micronized allogenic cartilage application with an excellent postoperative outcome. CONCLUSION: From the 3-month through 1-year follow-up, the patient continued a pain-free return to normal function. This case suggests that arthroscopy is as a viable approach to resurfacing osteochondral lesions of the big toe joint.

A Novel Insertional Achilles Tendon Rupture Repair After Heel Spur Debridement: A Case Report.

CASE: We report a case of a 46-year-old woman who suffered an insertional Achilles tendon rupture secondary to a fall after undergoing retrocalcaneal and Achilles tendon debridements with flexor tendon transfer. Examination revealed posterior ankle pain with insertional Achilles tendon retraction. Treatment options included continued immobilization vs. surgical repair. She underwent Achilles tendon tenodesis to the calcaneus using a combined gastrocsoleus recession and Krackow suture technique. CONCLUSION: At the 1-year follow-up, examination revealed pain-free return to normal function. In the presence of a ruptured Achilles tendon with retraction, this repair provided sufficient lengthening and fixation of the Achilles tendon complex.

Cost of Headless vs Headed Screw Fixation for Calcaneal Osteotomy and Subtalar Arthrodesis.

BACKGROUND: Screw head prominence in the heel following fixation for calcaneal osteotomy or subtalar arthrodesis has resulted in high rates of symptomatic hardware and screw removal. A cost analysis was performed to determine the financial implications of screw removal. Furthermore, we compared the rate of nonunion following fixation. METHODS: Current Procedural Terminology codes were used to identify all patients who had a subtalar arthrodesis or calcaneal osteotomy (with screw fixation) performed between 2010 and 2016. The cohort was divided into 2 groups: 7.0-mm headless screw or 6.7-mm headed screw. The primary outcome measure was the rate of symptomatic screw removal. Secondary outcomes included the rate of nonunion. The expense associated with symptomatic hardware removal was determined by cost analysis. RESULTS: Seventy-six patients underwent headless screw fixation, and 2 patients (2.6%) required screw removal. Fifty-four patients underwent headed screw fixation and 12 patients (22.2%) required screw removal. Symptomatic hardware removal was performed more frequently in the headed screw group (P < .001). There was no difference in the rate of nonunion after subtalar arthrodesis between the 2 groups (P = .363). The calcaneal osteotomy united in 100% of patients. There was a $51 755 cost savings per 100 cases using headless screw fixation. CONCLUSION: The rate of symptomatic screw removal was lower with headless screw fixation. The calcaneal osteotomy healed in 100% of patients, and there was no difference in the rate of subtalar nonunion between the 2 groups. Cost analysis demonstrated a significant benefit when the expense of hardware removal was considered. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Posterior Ankle Impingement and Flexor Hallucis Longus Pathology.

Posterior ankle pain is a common complaint, and the potential causative pathologic processes are diverse. The constellation of these numerous etiologies has been collectively referred to as posterior ankle impingement syndrome. The pain associated with posterior ankle impingement is caused by bony or soft tissue impingement of the posterior ankle while in terminal plantar flexion. This condition is most frequently encountered in athletes who participate in sports that involve forceful, or repetitive, ankle plantar flexion. This article discusses the associated pathology, diagnosis, conservative treatment, and surgical techniques associated with flexor hallucis longus and posterior ankle impingement syndrome.

Ankle Arthrodesis With Anterior Plate Fixation in Patients at High Risk for Nonunion.

Between January 1, 2011, and January 1, 2017, an orthopaedic foot and ankle surgeon performed tibiotalar arthrodesis on 221 patients. Thirty-two were included in this study. Inclusion criteria included patients with at least one risk factor for nonunion and/or malunion, isolated anterior ankle arthrodesis with plate fixation, patients older than 18, and a minimum of 1-year follow-up. Risk factors were avascular necrosis of the talus, severe segmental bone defect, smoking, inflammatory arthropathy, coronal deformity greater than 15°, diabetes mellitus, septic nonunion, failed ankle arthrodesis, and body mass index greater than 35. Functional outcome questionnaires (Ankle Osteoarthritis Score [AOS] and Foot Function Index [FFI]) were collected at the latest visit or by phone. Twenty-six (26/32, 81.2%) patients included in the study had computed tomography images available for review at an average of 3.2 months after surgery. The rate of successful arthrodesis was 93.8% (30/32) at an average of 78 days. Overall, 14 patients (14/32, 43.8%) developed a postoperative complication, including 1 patient that had a delayed nonunion and 2 patients that proceeded to nonunion. Twenty-three patients (23/32, 71.9%) completed the functional outcome questionnaires at an average of 26.8 months. Mean AOS and FFI scores improved significantly postoperatively (P < .001). Sagittal tibiotalar and coronal tibiotalar alignment improved significantly in patients with severe preoperative deformity (P < .001). Tibiotalar arthrodesis with anterior plate fixation in a high-risk cohort results in high union rates and significantly improved functional outcomes. Levels of Evidence: Therapeutic, Level IV: Prospective, comparative trial.

Two-Stage Varus Correction.

Coronal plane deformity following total ankle arthroplasty has been associated with poor clinical outcomes and early prosthesis failure. Neutral mechanical alignment and prosthetic joint stability must be achieved through meticulous surgical planning and precise technical execution. Cavovarus foot deformity and varus malalignment of the lower extremity is reviewed, with particular emphasis as it relates to total ankle arthroplasty. Correction of varus malalignment may be performed at the time of total ankle arthroplasty or as a 2-stage procedure. Surgeon experience, revision total ankle arthroplasty, and subtalar arthrodesis should be considerations when contemplating 2-stage varus correction.

The Missed Achilles Tear: Now what?

Chronic Achilles tendon ruptures are debilitating injuries and are often associated with large tendon gaps that can be challenging for the foot and ankle surgeon to treat. Preoperative evaluation should include the patient's functional goals, medical comorbidities, MRI assessment of gastrocsoleus muscle viability, condition of adjacent flexor tendons, and size of the tendon defect. Although several surgical techniques have been described, the surgeon must formulate an individualized treatment plan for the patient. This article reviews the principles of diagnosis, treatment options, and clinical outcomes, and outlines the authors' preferred techniques.

What to Do with the Spring Ligament.

The spring ligament complex is an important static restraint of the medial longitudinal arch of the foot and its failure has been associated with progressive flatfoot deformity. Reconstruction of the spring ligament complex is most appropriate in stage II posterior tibial tendon dysfunction, before severe peritalar subluxation and rigid deformity develops. Although an understanding of the spring ligament complex and its contribution to medial arch stability has grown, there is no unanimously accepted surgical technique that has consistently demonstrated satisfactory outcomes. This article reviews the pathoanatomy of the spring ligament complex and the role of spring ligament reconstruction in acquired flatfoot deformity, and highlights current research.

Patient-Reported Outcomes and Return to Activity After Peroneus Brevis Repair.

BACKGROUND: There is limited data on functional outcomes after primary repair of partial peroneal tendon tears. Previous reports have been limited by small cohorts, duration of follow-up, and often included both tenodesis and primary repair. The purpose of this study was to report the functional outcomes and return to activity in the largest cohort to date with partial peroneal tendon tears treated with primary repair. METHODS: A chart review identified all patients who underwent primary repair of the peroneus brevis tendon from 2008 to 2012. Demographic data, magnetic resonance imaging findings, and postoperative complications were reviewed. Patients were asked to complete a follow-up questionnaire, Foot and Ankle Ability Measure (FAAM), and Foot Function Index (FFI). There were 201 patients who underwent primary repair of the peroneus brevis tendon. The average age at time of operation was 44.3 years. Seventy-one patients returned the follow-up questionnaires with an average follow-up of 4.6 years. Fifty-two patients completed the FFI questionnaire preoperatively and postoperatively. RESULTS: Fifty-nine patients (83.1%) reported a return to regular exercise and sports at final follow-up. At 1 year postoperatively, 76.5% of patients returned to the same preinjury activities, and 62.3% returned to the same level of preinjury activity. Furthermore, 85.9% of patients were satisfied with their outcome, and 91.4% of patients reported they would choose to undergo the same procedure again. The mean FAAM score was 85.2 at follow-up. The mean preoperative and postoperative FFI score was 41.1 and 12.2, respectively. There was a significant improvement in the FFI score of 28.9 after primary peroneus brevis tendon repair (P < .001). CONCLUSION: Primary repair of peroneus brevis tendon provided consistent improvement in functional outcomes in the majority of patients, as measured by a validated scoring system, the FFI. FAAM scores demonstrated good function compared to historical controls. The majority of patients were able to return to preinjury activity. LEVEL OF EVIDENCE: Level IV, retrospective case series.