Review of Classification Systems for Adult Acquired Flatfoot Deformity/Progressive Collapsing Foot Deformity and the Novel Development of the Triple Classification Delinking Instability/Deformity/Reactivity and Foot Type.

Background: Classifications of AAFD/PCFD have evolved with an increased understanding of the pathology involved. A review of classification systems helps identify deficiencies and respective contributions to the evolution in understanding the classification of AAFD/PCFD. Methods: Using multiple electronic database searches (Medline, PubMed) and Google search, original papers classifying AAFD/PCFD were identified. Nine original papers were identified that met the inclusion criteria. Results: Johnson's original classification and multiple variants provided a significant leap in understanding and communicating the pathology but remained tibialis posterior tendon-focused. Drawbacks of these classifications include the implication of causality, linearity of progression through stages, an oversimplification of stage 2 deformity, and a failure to understand that multiple tendons react, not just tibialis posterior. Later classifications, such as the PCFD classification, are deformity-centric. Early ligament laxity/instability in normal attitude feet and all stages of cavus feet can present with pain and instability with minor/no deformity. These may not be captured in deformity-based classifications. The authors developed the 'Triple Classification' (TC) understanding that primary pathology is a progressive ligament failure/laxity that presents as tendon reactivity, deformity, and painful impingement, variably manifested depending on starting foot morphology. In this classification, starting foot morphology is typed, ligament laxities are staged, and deformity is zoned. Conclusions: This review has used identified deficiencies within classification systems for AAFD/PCFD to delink ligament laxity, deformity, and foot type and develop the 'Triple classification'. Advantages of the TC may include representing foot types with no deformity, defining complex secondary instabilities, delinking foot types, tendon reactivity/ligament instability, and deformity to represent these independently in a new classification system. Level of Evidence: Level V.

Acute staphylococcal hind foot osteomyelitis in a healthy adult: A case report.

INTRODUCTION: Acute osteomyelitis of the hind foot is uncommon in a normal immunocompetent adult. CASE PRESENTATION: We present a previously healthy 52 year old caucasian male who developed painful swelling of his ankle/hindfoot following closed soft tissue football injury. He had no antecedent systemic symptoms. Magnetic resonance imaging and bone scan imaging, followed by surgical decompression and bone biopsy confirmed a diagnosis of Staphylococcus aureus hind foot osteomyelitis. He underwent triple fusion after debridement and had suppressive antibiotics. His pain and swelling resolved at 6 weeks postoperation and CT confirmed fusion at 6 months. His inflammatory markers normalised over the course of 7 months. After 18 months, he remained asymptomatic without any evidence of recurrence. CONCLUSION: This case represents an unusual and important variation of presentation of acute osteomyelitis in a healthy adult. It can be easily overlooked when a normal patient presents with pain and functional impairment after a closed soft tissue trauma, but a high index of suspicion is paramount because virulent organisms can infect immunologically normal patients.

Experience of an isolated use of low-intensity pulsed ultrasound therapy on fracture healing in established non-unions: a prospective case series.

Fracture non-unions are responsible for approximately 5% of cases, with low expectation of spontaneous healing thereafter. The fractures that heal without complications can take months to heal completely. An ultrasound, typically at low intensities (0.5-50 mW/cm2), serves a diagnostic purpose, whereas at higher intensities (0.2-100 W/cm2), its role becomes more therapeutic by generating heat energy. Low-intensity pulsed ultrasound (LIPUS) is frequently used to stimulate or to accelerate fracture healing. We present a prospective review of fracture non-unions treated with low-intensity pulsed ultrasound (LIPUS). We enrolled 66 patients during August 2016 and December 2018, 38 males and 28 females; age range 19-85 years (average 49.2 years). All these patients were followed up to minimum 6 months. The average time of referral post-treatment for fractures was 8.2 months (range 6-18 months). Four patients were excluded due to various reasons. 39 out of 62 fractures showed successful healing with symptom improvement and callus formation with 67% success rate. In this case series, we noted LIPUS therapy failure in the post-ORIF scaphoid fracture and post-ankle joint fusion non-union. We did not observe any influence of a medical condition such as diabetes mellitus, osteoporosis or personal habits like smoking. The LIPUS therapy appears to have influence on bone healing, depending on the onset of therapy, fracture type and the approach to fracture care. In this case series, the compliant group showed 67% successful outcome.

Acquired cavo-varus deformity caused by an accessory calcaneus: a case report and literature review.

We describe an unusual cause of an acquired cavo-varus foot deformity produced by progressive enlargement of an accessory calcaneal ossicle. A 13-year-old boy with constitutional plano-valgus flat feet noted a gradual change in foot shape associated with lateral ankle pain on ambulation following an inversion injury 2 years earlier. CT and MRI scans confirmed a large accessory calcaneal ossicle lying within the sinus tarsi, with associated marrow oedema. Following surgical excision of the ossicle, the foot returned to its original shape and the symptoms were alleviated. This is the fifth reported case of an accessory calcaneal ossicle, but the only case that has occurred in a flatfooted individual. We also present the first reported MRI images of the lesion confirming pathological marrow oedema as a response to mechanical stress.

The resistance to failure of spring ligament reconstruction.

INTRODUCTION: The spring ligament (SL) is increasingly recognised as the major structure that fails in acquired adult flatfoot deformity (AAFD). This is the first study that demonstrates integrity of repair of the SL. PATIENTS AND METHODS: Six pairs of fresh frozen cadavers were setup in a standardised fashion with ankle in plantargrade (mean age 59 years, BMI 25). A 25N lateral force was applied to the medial metatarsal head using an algometer. Lateral displacement of the foot was measured with SL intact, sectioned, following FibreWire® repair, then Arthrex InternalBrace (IB) reconstruction, then with selective sectioning of each limb of the IB reconstruction. RESULTS: In 12 specimens, overall lateral translation with SL intact was 21mm±4.9. This increased to 39.2mm±10.9 (p<0.05) with SL sectioning, no significant improvement to 34.2mm±9.5 with repair (p=0.159), before significantly returning to baseline 16.55mm±5.1 (p<0.001) with the IB. Augmenting with FDL did not influence lateral translation (p=0.586). CONCLUSION: Restoration of SL integrity is fundamental to prevent flatfoot. This study shows traditional repair models fail to provide sufficient resistance to planovalgus. Using an augmented device such as the IB provides optimal resistance to lateral translation and hence planovalgus, particularly the plantar limb of the augmentation.

Calcaneal osteomyelitis presenting with acute tarsal tunnel syndrome: a case report.

INTRODUCTION: Cases of acute tarsal tunnel syndrome are rare. To the best of our knowledge, we describe the only reported case of acute posterior tibial nerve compression resulting from adjacent haemotogenous pyogenic calcaneal osteomyelitis. CASE PRESENTATION: A previously healthy 38-year-old Caucasian woman developed symptoms of acute tarsal tunnel syndrome in her right foot over a six-day period. No antecedent trauma or systemic symptoms were noted. Magnetic resonance imaging and bone scan imaging, followed by surgical decompression and bone biopsy confirmed a diagnosis of Staphylococcus aureus calcaneal osteomyelitis. Her pain and paraesthesia disappeared after the operation, while her inflammatory markers normalised during a 12-week course of antibiotics. After four years she has remained asymptomatic without any indication of recurrence. CONCLUSION: This case is not just unique in describing osteomyelitis as a cause of tarsal tunnel syndrome, because haemotogenous calcaneal osteomyelitis is in itself a rare pathology. We recommend considering infection as a differential diagnosis in patients presenting with acute tarsal tunnel syndrome.

Transient osteoporosis of the foot.

Transient osteoporosis is a rare cause of pain in the foot. There is a broad differential diagnosis. A multidisciplinary assessment by both an orthopaedic surgeon and rheumatologist with review of the imaging by a radiologist is useful, as this condition is a diagnosis of exclusion.

Lauge-Hansen classification--a literature review.

The Lauge-Hansen classification of ankle fractures is a historical landmark in fracture research. Despite this there are, however, some shortcomings in methodology and several papers have demonstrated poor reproducibility. This paper reviews Lauge-Hansen's work and the literature evaluating his classification.