Category:
Trauma; Midfoot/Forefoot
Introduction/Purpose:
Fractures of the proximal fifth metatarsal are common injuries with a unique history. Treatment of these fractures is controversial, in part ...due to confusion regarding the nomenclature of the fracture subtypes. The most commonly utilized classification system is the Lawrence and Botte classification, which separates fractures into zones 1, 2, and 3 based on their relationship to the tuberosity and the 4th-5th intermetatarsal articulation. The purpose of this study was to evaluate the inter-rater and intra-rater reliability of the Lawrence and Botte classification of fifth metatarsal base fractures.
Methods:
Thirty sets of x-rays representing an equal number of zone 1, zone 2 and zone 3 fractures of varying chronicity were sent to eleven fellowship trained orthopedic foot and ankle surgeons. Surgeons were asked to classify each fracture according to the Lawrence and Botte classification system (round 1). No review of the classification system or visual aids were provided. Two weeks later, the same set of x-rays were reordered and renumbered in a random fashion. The surgeons then re-classified each fracture in a blinded fashion under the same conditions (round 2). Inter-rater and intra-rater reliability was summarized using the kappa statistic. To determine the source of variability between the zones, additional analyses were performed to determine the kappa statistic for a) combined zone 1 and 2 fractures versus zone 3 fractures and b) combined zone 2 and 3 fractures versus zone 1 fractures.
Results:
The Lawrence and Botte classification demonstrated substantial overall inter-rater agreement for both rounds 1 and 2 (kappa = 0.66 and 0.65, respectively). Zone 1 fractures demonstrated the highest inter-rater reliability (kappa = 0.83 and 0.83). There was moderate agreement for zone 2 fractures (kappa = 0.51 and 0.50). There was substantial agreement for zone 3 fractures (kappa = 0.64 and 0.65). Dichotomous evaluation of the zone 1 vs. combined zones 2-3 boundary yielded excellent agreement (kappa = 0.83, 0.83). The combined zones 1-2 vs. zone 3 boundary yielded a much lower agreement (kappa = 0.66, 0.65). Intra-rater reliability varied by individual, with kappa values ranging from 0.60 to 0.90, corresponding to modest to almost perfect agreement.
Conclusion:
The Lawrence and Botte classification system has overall substantial inter-rater and intra-rater reliability, but assessment of the interface between zone 2 and zone 3 fractures is much less reliable than that between zone 1 and zone 2. Previous studies of isolated zone 1 fractures most likely contain a homogenous fracture cohort, while studies of zone 2 or zone 3 fractures are likely to include a mixture of fracture types. Future studies may utilize supplemental imaging or modify the classification to best determine treatment of these more distal fractures.
Highlights • Anterior ankle impingement is a common cause of chronic ankle pain, particularly in athletic populations. • Advancements in ankle arthroscopy have decreased the risk of complications. • ...A comprehensive understanding of diagnosis and surgical technique can influence patient outcomes. • The purpose of this review is to review the evidence-based outcomes of arthroscopic management for anterior ankle impingement.
Category:
Basic Sciences/Biologics; Hindfoot; Other
Introduction/Purpose:
Flexor digitorum longus (FDL) transfer, in conjunction with osseous procedures, is used routinely for the treatment of ...posterior tibial tendon dysfunction (PTTD). It is well established however that the relative power of the FDL tendon is significantly inferior than that of the native posterior tibial tendon. The purpose of this study is to systematically evaluate the evidence that supports or refutes the use of an FDL transfer in the surgical treatment of PTTD.
Methods:
A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta- Analysis. Using the terms 'flexor digitorum longus OR FDL AND posterior tibial tendon dysfunction OR PTTD OR adult acquired flatfoot OR AAFD' we searched the PubMed/Medline database. Both clinical and biomechanical studies were eligible for inclusion.
Results:
Forty-one studies met the inclusion criteria, including 31 clinical studies and 10 biomechanical in vitro studies. All 31 clinical studies consisted of Level IV evidence, and support the use of an FDL transfer. There was significant heterogeneity of the clinical evidence due to the variety of concomitant procedures. Of the 10 biomechanical in vitro studies, 2 support the use of an FDL transfer, although these did not assess the procedure in isolation. 8 biomechanical in vitro studies specifically assessing the effect on of an FDL transfer contradict its use for PTTD.
Conclusion:
There is poor quality clinical evidence to support the use of an FDL transfer for PTTD and the biomechanical literature refutes the use of the procedure. It remains unknown if the clinical improvement reported in the literature can be attributed to the FDL transfer or the concomitant osseous procedures. Additional studies are needed to assess the validity of the FDL transfer and whether alternatives are available to preserve the PTT muscle.
Category:
Ankle Arthritis; Ankle; Hindfoot; Midfoot/Forefoot
Introduction/Purpose:
Medial displacement calcaneal osteotomies (MDCO) and first ray plantarflexion osteotomies, such as a Cotton ...osteotomy, are frequently used realignment procedures for hindfoot and ankle joint valgus malalignment. Multiple studies demonstrated the effects of calcaneal osteotomies on the contact pressures of the ankle joint (CPAJ), with slight medial displacement of the center of pressure and lateral unloading of the ankle joint. However, the influence of a first ray plantarflexion osteotomy on the CPAJ is yet to be determined. In this cadaveric study, we compared the effects of calcaneal and first ray osteotomies in the CPAJ.
Methods:
Fifteen bellow-knee cadaveric specimens were used. Tekscan 5033 sensors were placed in the ankle joint and held with cyanoacrylate. Specimens were loaded in a servohydraulic load frame. Tension loads applied to tendons: Achilles (200N), PTT (40N), peroneals combined (44N), FHL/FDL combined (35N). Specimens were tested in intact position, isolated MDCO (6 and 10mm), isolated Cotton osteotomies (4 and 8mm) and combined MDCO/Cotton osteotomies (10mm and 8mm, respectively).
Specimens were then cyclically loaded from 100N-1000N at a rate of 0.5Hz for 30 cycles while CPAJ data was collected at a rate of 20Hz. Average and maximum overall pressure data were extracted as well as the center of pressure (CoP) movement in the anteroposterior (AP) and medial to lateral (ML) directions. Data was also analyzed when divided into lateral, central, and medial areas of the contact pressure map. Groups were compared by the Wilcoxon test. P-values <0.05 were considered significant. Results: We found significant (p<0.05) and progressive decrease in the average and maximum CPAJ when comparing intact ankle (1624 and 1964kPa), MDCO (1526 and 1891 kPa), Cotton osteotomy (1370 and 1642 kPa) and combined osteotomies (1292 and 1599 kPa). Cotton (4 and 8mm) and combined osteotomies showed similar contact pressures, that were significantly lower than intact specimens, emphasizing the power of first ray osteotomies in changing the contact pressures of the ankle joint. When accounting for medial, central and lateral aspects of the joint, we found that the decrease in the pressures was only significant in the central (cotton and combined osteotomies) and lateral aspects (combined osteotomy only).No significant differences were found in CoP measurements (both AP ad ML directions).
Conclusion:
The results of this cadaveric study demonstrate the power of Cotton osteotomies, in isolation or combined with MDCO, in decreasing the overall CPAJ, especially on its central and lateral aspects. MDCO in isolation did not differ from intact specimens. No significant changes in the center of pressure of the ankle joint were noted following any of the performed osteotomies (combined or isolated). Our findings should guide surgeons when deciding between first ray and calcaneal osteotomies as realignment procedures for hindfoot and ankle valgus deformities, when aiming to unload the lateral aspect of the ankle joint.
Figure 1.
Category:
Basic Sciences/Biologics; Ankle; Hindfoot
Introduction/Purpose:
The tall Controlled Ankle Motion (CAM) boot and the short CAM boot are commonly used devices to immobilize the foot and ...ankle. However, the effect of these devices on joint contact pressures is unknown. The objective of this study is to assess the effect of the tall CAM boot and short CAM boot on contact pressures of the ankle, subtalar, talonavicular, and calcaneocuboid joints. We hypothesize that both the tall CAM boot and short CAM boot will reduce contact pressures of the ankle and hindfoot joints, with the tall CAM boot having the greatest effect.
Methods:
Eight lower extremity cadaver specimens were mounted on a servohydraulic test frame. The specimens were loaded to 700 N at a cyclical frequency of 1 Hz with the posterior tibial, peroneus longus, peroneus brevis, flexor hallucis longus, flexor digitorum longus, and Achilles tendon physiologically tensioned. TekScan (TekScan, Boston, MA) pressure sensors were placed in the ankle, subtalar, talonavicular, and calcaneocuboid joints. In the sagittal plane, the specimens were loaded on a neutral surface, followed by 20o of dorsiflexion. Each specimen served as its own control, with contact pressures measured with no immobilization (control), followed by placement in a short CAM boot and tall CAM boot. In addition, contact pressures in the immobilized limbs were measured at muscle loads both equal to and half of the load applied to the control in order to account for decreased muscle activation during immobilization.
Results:
There was no difference in the average and peak contact pressures of the ankle, subtalar, talonavicular and calcaneocuboid joints when comparing the short CAM boot to no immobilization at equal tendon loads. The tall CAM boot significantly decreased average and peak contact pressures of the ankle, subtalar, and talonavicular joints when compared to no immobilization. The tall CAM decreased the contact pressures of the talonavicular and subtalar joint to a greater degree than the ankle joint. The reduction in contact pressures was accentuated when the load applied to the tendons was decreased in accordance with diminished muscle activation during immobilization. Neither immobilization device decreased the contact pressures of the calcaneocuboid joint at equal tendon loads. Neither CAM boot changed the center of pressure of any joint.
Conclusion:
Immobilization in a tall CAM boot decreases contact pressures of the ankle and hindfoot in both a neutral position and in dorsiflexion. A tall CAM boot should be used clinically if the goal of its use is to maximally reduce contact pressures of the ankle and hindfoot. The tall CAM boot is better at reducing the contact pressures of the subtalar and talonavicular joint than the ankle joint.
Category:
Ankle, Hindfoot
Introduction/Purpose:
The tall Controlled Ankle Motion (CAM) boot and the short CAM boot are commonly used devices to immobilize the foot and ankle. These devices are ...preferably used instead of casts and splints as they are easily removed, allowing possible wound examination, personal hygiene, and therapeutic exercises. However, the effect of these devices on joint contact pressures is unknown. The aim of this study is to assess the effect of the tall CAM boot and short CAM boot on contact pressures of the ankle, subtalar, talonavicular, and calcaneocuboid joints. We hypothesize that both the tall CAM boot and short CAM boot will reduce contact pressures of the ankle and hindfoot joints, with the tall CAM boot having the greatest effect.
Methods:
Eight lower extremity cadaver specimens were mounted on a servohydraulic test frame. The specimens were loaded to 700 N at a cyclical frequency of 1 Hz with the posterior tibial, peroneus longus, peroneus brevis, flexor hallucis longus, flexor digitorum longus, and Achilles tendon physiologically tensioned. TekScan (TekScan, Boston, MA) pressure sensors were placed in the ankle, subtalar, talonavicular, and calcaneocuboid joints. In the sagittal plane, the specimens were loaded on a neutral surface, followed by 20o of dorsiflexion. Each specimen served as its own control, with contact pressures measured with no immobilization (control), followed by placement in a short CAM boot and tall CAM boot. In addition, contact pressures in the immobilized limbs were measured at muscle loads both equal to and half of the load applied to the control in order to account for decreased muscle activation during immobilization.
Results:
There was no difference in the average and peak contact pressures of the ankle, subtalar, talonavicular and calcaneocuboid joints when comparing the short CAM boot to no immobilization at equal tendon loads. The tall CAM boot significantly decreased average and peak contact pressures of the ankle, subtalar, and talonavicular joints when compared to no immobilization. The reduction in contact pressures was accentuated when the load applied to the tendons was decreased in accordance with diminished muscle activation during immobilization. Neither immobilization device decreased the contact pressures of the calcaneocuboid joint at equal tendon loads.
Conclusion:
Immobilization in a tall CAM boot decreases contact pressures of the ankle and hindfoot in both a neutral position and in dorsiflexion. A tall CAM boot should be used clinically if the goal of its use is to maximally reduce contact pressures of the ankle and hindfoot.
Category:
Ankle, Ankle Arthritis
Introduction/Purpose:
A major complication of total ankle replacement (TAR) is a periprosthetic joint infection (PJI). The reported rate of this complication ranges ...between 2.4 – 8.9%. Identifying preoperative patient characteristics that correlate with an increased risk of PJI is of great interest to orthopaedic surgeons, as this may assist with appropriate patient selection. The purpose of this study is to systematically review the literature to identify risk factors that are associated with PJI following TAR.
Methods:
Utilizing the terms “(risk factor OR risk OR risks) AND (infection OR infected) AND (ankle replacement OR ankle arthroplasty)” we searched the PubMed/MEDLINE electronic databases. Using the PRISMA guidelines, studies were selected for inclusion if they assessed clinical risk factors for developing a PJI following TAR. In addition, the reference lists of included studies were also reviewed and compared to the collected studies to ensure that no pertinent papers were omitted. The quality of the included studies was then assessed using the American Academy of Orthopaedic Surgeons Clinical Practice Guideline and Systematic Review Methodology. Recommendations were made using the overall strength of evidence.
Results:
Eight studies met the inclusion criteria, totaling 12,704 patients who underwent a TAR. A limited strength of recommendation can be made that the following preoperative patient characteristics correlate with an increased risk of PJI following TAR: inflammatory arthritis, prior ankle surgery, age greater than 65 years, body mass index less than 19, peripheral vascular disease, chronic lung disease, hypothyroidism, and low preoperative AOFAS hindfoot scores. There is conflicting evidence in the literature regarding the effect of obesity, tobacco use, diabetes, and duration of surgery.
Conclusion:
Several risk factors were identified as having an association with PJI following TAR. These factors may alert surgeons that a higher rate of PJI is possible. However, because of the low level of evidence of reported studies, only a limited strength of recommendation can be ascribed to regard these as risk factors for PJI at this time.
Category:
Basic Sciences/Biologics; Midfoot/Forefoot
Introduction/Purpose:
Zone 1 5th metatarsal base fractures are more common than zone 2 or 3 fractures, but significant debate still exists as to ...their optimum management, particularly for large fragments. The objective of this study was to compare the biomechanical strength of two headless compression screws versus a hook plate for fixation of large zone 1 5th metatarsal fractures. We hypothesized that hook plates would be biomechanically superior.
Methods:
Ten matched pairs of fresh-frozen 5th metatarsal cadaveric specimens were used. Large zone 1 avulsion fractures were simulated. Specimens were randomly assigned to fixation with two 2.5-mm headless compression screws or an anatomic 5th metatarsal hook plate. Specimens were mounted on a test frame and cyclically loaded through the plantar fascia, peroneus brevis tendon, and metatarsal base. Each specimen underwent 100 cycles at 50% physiological load (12 N on bone, 70 N on plantar fascia, 17.5 N on peroneus brevis), 100 cycles at 75% load (18 N on bone, 105 N on fascia, 26.25 N on peroneus brevis), and 100 cycles at 100% load (24 N on bone, 140 N on fascia, 35 N on peroneus brevis). Maximum cycles and maximum force were recorded.
Results:
The hook plate group had significantly higher cycles to completion of loading or failure compared with the screw group (270.7 +- 66.0 range 100-300 cycles versus 178.6 +- 95.7 range 24-300 cycles, respectively; P=0.011). Seven of 10 hook plate specimens and 2 of 10 screw specimens were intact at the maximum 300 cycles. Mean maximum force on the plantar fascia did not differ between the plate and screw groups (133.0 +- 22.1 range 70-140) N versus 119.0 +- 4.5 (range 70-140) N, respectively; P=0.098). Nine of 10 plate specimens and 5 of 10 screw specimens were intact at maximum force of 140 N.
Conclusion:
To our knowledge, this is the first biomechanical study comparing fixation constructs for 5th metatarsal avulsion fractures while loading the plantar fascia, which is the primary deforming force in vivo. These data suggest an anatomic hook plate is biomechanically superior to headless compression screw fixation of large zone 1 5th metatarsal avulsion fractures, which may prove pertinent in the setting of morbid obesity, fracture comminution, and/or fracture nonunion. Limitations include the relatively small sample size and the use of cadaveric bone which imperfectly mimics living tissue.
Category:
Ankle, Hindfoot
Introduction/Purpose:
Medial displacement calcaneal osteotomies (MDCO) and first ray plantarflexion osteotomies, such as a Cotton osteotomy, are frequently used realignment ...procedures for hindfoot and ankle joint valgus malalignment. Multiple studies demonstrated the effects of calcaneal osteotomies on the contact pressures of the ankle joint (CPAJ), with slight medial displacement of the center of pressure and lateral unloading of the ankle joint. However, the influence of a first ray plantarflexion osteotomy on the CPAJ is yet to be determined. In this cadaveric study we compared the effects of calcaneal and first ray osteotomies in the CPAJ.
Methods:
Fifteen bellow-knee cadaveric specimens were dissected to expose the ankle joint and isolate the flexor and peroneal tendons. Tekscan 5033 sensors were placed in the ankle joint and held in place with cyanoacrylate. Specimens were loaded in a servohydraulic load frame. The following loads were applied to the tendons: Achilles (200 N), PTT (40 N), peroneals combined (44 N), FHL/FDL combined (35 N). Ankles were tested in an intact position, after isolated MDCO (6, 8, 10 and 12 mm), isolated Cotton osteotomies (4, 8 and 12 mm) as well as combined osteotomies (10 mm and 12 mm, respectively). Specimens were then cyclically load from 100N-700 N at a rate of 0.5 Hz for 30 cycles while CPAJ data was collected at a rate of 20 Hz. Average and maximum pressure data were extracted as well as the center of pressure (CoP) movement in the AP and ML directions.
Results:
There was a significant (p<0.05) and progressive decrease in respective maximum and average contact pressures of the ankle joint when comparing intact ankle (1608 and 1312kPa), calcaneal osteotomy (1291 and 1034 kPa), Cotton osteotomy (1165 and 962 kPa) and combined osteotomies (1134 and 903 kPa). Cotton osteotomy and combined osteotomies showed similar contact pressures. Regarding CoP measurements of the ankle joint, native ankle and MDCO demonstrated similar positionings in the sagittal and coronal planes. Cotton and combined osteotomies caused a significant shift of the CoP anteriorly and laterally when compared respectively to the intact/MDCO and MDCO ankles.
Conclusion:
The results of this study demonstrate that the Cotton osteotomy has a greater effect on the contact pressures of the ankle when compared to the MDCO. There is an overall decrease in the maximum and average pressures as well as a deviation of the center of pressure toward the anterior and lateral aspect of the ankle joint. These findings should guide surgeons when deciding between first ray and calcaneal osteotomies as realignment procedures for hindfoot and ankle valgus deformities.
Category: Other Introduction/Purpose: Hallux rigidus is one of the most common pathologies afflicting the foot. Various joint salvage techniques have been described with a multitude of different ...implants. Recently, a synthetic cartilage implant composed of polyvinyl alcohol (PVA) received FDA premarket approval for treatment of arthritis of the great toe and has been used in over 4,000 cases. The purpose of this study was to systematically review the clinical evidence supporting the use of a PVA implant in hallux rigidus. Methods: A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). Using the terms “cartiva OR polyvinyl alcohol OR synthetic cartilage OR hemiarthroplasty AND hallux rigidus OR great toe arthritis OR first toe arthritis “ we searched the PubMed/Medline database in December 2017. In addition, the reference list of publications were scanned for further relevant studies. Results: 4 studies met the inclusion criteria, all of which were derived from a single randomized controlled trial. At short-term follow-up (2 years), patients undergoing placement of a PVA implant had significant improvement in Foot and Ankle Ability Measure (FAAM) sports and activity of daily living, as well as VAS pain scores. The outcomes of the surgery were found to be noninferior compared to arthrodesis. At intermediate follow-up (5 years), the improvement in clinical outcomes persisted and implant survivorship was 96%. Conclusion: There are limited studies available detailing the outcomes of a PVA implant for hallux rigidus, however the results that are available demonstrate a high level of evidence. There are no long-term publications assessing the outcomes of a PVA implant for hallux rigidus.
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