Outcomes of Total Ankle Arthroplasty After Periprosthetic Cyst Curettage and Bone Grafting.

Total ankle arthroplasty (TAA) has become a popular management option for ankle arthritis. Periprosthetic osteolysis is one of the most common causes for reoperation in TAA. A CT scan should be done in all suspected osteolysis cases to confirm location, quantify size and aid in surgical planning. These patients are often asymptomatic with limited evidence regarding appropriate management. Smaller lesions should be monitored for progression in size. Periprosthetic cysts measuring 10-15mm in all three axes should be considered for debridment and curettage with autogenous bone grafting. The authors believe that bone grafting of large asymptomatic periprosthetic cysts could prevent implant failure.

Tumor induced osteomalacia from a peripheral mesenchymal tumour of the foot.

Tumour induced osteomalacia (TIO) is a rare condition caused by peripheral mesenchymal tumours (PMT) which produce fibroblast-growth factor 23 (FGF23). FGF23 inhibits renal phosphate reabsorption leading to vitamin D resistant osteomalacia. The rarity of the condition and difficulty with isolating the PMT make diagnosis difficult, with delayed treatment leading to significant patient morbidity. We present a case of PMT of the foot with TIO, with a discussion on diagnosis and treatment.

CT Scan Assessment and Functional Outcome of Periprosthetic Bone Grafting After Total Ankle Arthroplasty at Medium-term Follow-up.

BACKGROUND: Periprosthetic cysts can occur in up to 95% of total ankle arthroplasties (TAA) and have been correlated with implant failure. The aim of this study was to determine the clinical and radiologic outcomes, using computed tomographic (CT) scan, after periprosthetic cyst bone grafting and assess for the minimum cyst size that should be grafted. METHODS: A retrospective review was performed of all TAA procedures performed between 2007 and 2014 (n=93). A CT scan was done to assess cyst size and operative planning. Eight patients with 9 periprosthetic cysts larger than 1.75 cm3 were grafted and specimens sent for histology. The mean time to bone grafting was 7.3 (3.8-9.5) years. Functional outcome was assessed using the American Orthopaedic Foot & Ankle Society ankle score, visual analog scale, and Self-reported Foot and Ankle Score. A CT scan was performed at follow-up to assess graft incorporation and cyst size progression. The mean time to CT scan post grafting was 3.0 (0.7-4.7) years. RESULTS: There was no implant malalignment identified and no differences in the pre- and postoperative functional scores. Preoperatively cysts had a mean volume of 8.16 (2.04-14.03) cm3. The mean percentage incorporation was 89% (69%-100%). Eight of the grafted cysts were considered successful on CT, with the ninth having 69% incorporation. Five cysts were not grafted, as they were below 1.75 cm3, and remained the same size or had minimal enlargement. CONCLUSION: The satisfactory results in this small cohort suggests that prophylactic bone grafting may extend implant survival. We recommend that periprosthetic cysts greater than 1.75 cm3 be prophylactically bone grafted, and that cysts smaller than 1.75 cm3 be monitored for progression in size. LEVEL OF EVIDENCE: Level IV, Case Series.

Reliability of the Radiographic Measurement of the Hallux Interphalangeal Angle.

BACKGROUND: The hallux valgus interphalangeus (HVI) deformity has a common association with hallux valgus and hallux rigidus. The HVI is formed by the angle between the long axes of the proximal and distal phalanges. The normal value for this angular deformity in the coronal plane is less than 10°. The aim of this study was to analyze the intra- and inter-observer reliability of measuring the interphalangeal angle by orthopaedic surgeons. This study is the first study to evaluate specifically the reliability and reproducibility of measuring the HVI angle. METHODS: Twenty-one X-ray prints of weightbearing feet constituted a set. Sixteen qualified orthopaedic surgeons were asked to measure the HVI angle of all 21 X-ray images in the set. Three randomized sets were sent to each evaluator at 4-week intervals. After all 3 sets were measured, data were retrieved and statistically analyzed to determine the inter- and intraobserver variability and reliability in the measurement of the HVI angle. Reproducibility of the HVI measurement was assessed using 3 categories, which included the ability to measure the same angle 3 times and achieve: 3° or less, 5° or less, and more than 5° variation. RESULTS: The intraobserver reliability was found to be 5° or less in 85.2% of participants and the interobserver reliability was 81.2%. The researcher did not find significant correlation between the surgeons' level of experience with regard to the reliability of measuring the HVI angle. CONCLUSION: The inter- and intraobserver reliabilities of measuring the HVI angle is 81.2% and 85.2%, respectively. The level of experience of the surgeon does not improve this reliability. LEVELS OF EVIDENCE: Level II.

A new lesser metatarsophalangeal joint replacement arthroplasty design - in vitro and cadaver studies.

BACKGROUND: Isolated degenerative joint disease and/or Freiberg's infraction of the lesser metatarsophalangeal joint, although not frequent may become debilitating in the younger individual. Currently, once conservative management fails, the mainstay of treatment is debridement and excision-interposition arthroplasty. Replacement arthroplasty has been ineffective in the long term as the joints are subject to severe repetitive fatigue loading over small articulating surfaces through a wide range of motion. This is an in vitro and cadaver study of a new design replacement arthroplasty developed by the senior author. The aim of this study is to evaluate this novel replacement arthroplasty of the lesser metatarsophalangeal joint in a laboratory setting and cadaver implantation. METHODS: This three-component mobile bearing device is made of titanium and high density polyethylene which evolved over 4 years. It was subjected to 5,000,000 cycles in a laboratory under physiological and excessive forces to assess resistance to fatigue failure and wear pattern of the polyethylene liner. Following these tests, it was implanted in 15 fresh frozen cadavers at various stages of its development, during which the surgical technique was perfected. Range of motion and stability was tested using custom made instrumentation in four cadavers. The implant was inserted in a further two cadavers by an independent foot and ankle surgeon to check reproducibility. RESULTS: The device showed almost no signs of wear or surface deformation under physiological forces. The surgical technique was found to be simple and reproducible in the cadaver trial. The average dorsiflexion was 28.5° and 28.9° pre- and post-implant respectively. The average plantar flexion was 33.8° and 20.8° pre- and post- implant respectively. The joints were stable both pre- and post-operatively. Post-operative stability was objectively assessed for dorsal displacement and dorsiflexion using a 5 kgf (49 N) and was found to be excellent. CONCLUSION: This novel lesser metatarsophalangeal joint replacement arthroplasty has been developed as an option in the surgical treatment of symptomatic degenerative joint disease and/or Freiberg's infraction resistant to conservative treatment. The implant was found to be durable and resistant to wear in the laboratory testing. The cadaver studies have shown it to require minimal specialized instrumentation with good surgical reproducibility. This proof of concept study is the basis for clinical trials.

Fixation Techniques: Proceedings of the International Consensus Meeting on Cartilage Repair of the Ankle.

BACKGROUND: The evidence supporting best practice guidelines in the field of cartilage repair of the ankle is based on both low quality and low levels of evidence. Therefore, an international consensus group of experts was convened to collaboratively advance toward consensus opinions based on the best available evidence on key topics within cartilage repair of the ankle. The purpose of this article is to report the consensus statements on "Fixation Techniques" developed at the 2017 International Consensus Meeting on Cartilage Repair of the Ankle. METHODS: Seventy-five international experts in cartilage repair of the ankle representing 25 countries and 1 territory were convened and participated in a process based on the Delphi method of achieving consensus. Questions and statements were drafted within 11 working groups focusing on specific topics within cartilage repair of the ankle, after which a comprehensive literature review was performed and the available evidence for each statement was graded. Discussion and debate occurred in cases where statements were not agreed upon in unanimous fashion within the working groups. A final vote was then held, and the strength of consensus was characterized as follows: consensus, 51% to 74%; strong consensus, 75% to 99%; and unanimous, 100%. RESULTS: A total of 15 statements on fixation techniques reached consensus during the 2017 International Consensus Meeting on Cartilage Repair of the Ankle. All 15 statements achieved strong consensus, with at least 82% agreement. CONCLUSIONS: This international consensus derived from leaders in the field will assist clinicians with using fixation techniques in the treatment of osteochondral lesions of the talus.

Association Between Plantar Fasciitis and Isolated Gastrocnemius Tightness.

BACKGROUND: An association between plantar fasciitis and isolated gastrocnemius tightness (IGT) has been postulated in the literature; however, there have been few studies to prove this relationship. This prospective cross-sectional cohort study was aimed at determining the association between plantar fasciitis and IGT. METHODS: Three groups comprising 45 patients with plantar fasciitis (group 1), 117 patients with foot and ankle pathology other than plantar fasciitis (group 2), and 61 patients without foot and ankle pathology (group 3) were examined for the presence of IGT using the Silfverskiöld test. Statistical tests included chi-square test, Student t test, and analysis of variance. RESULTS: Of the patients, 101 (45.3%) had IGT: 36 (80%) in group 1, 53 (45.3%) in group 2, and 12 (19.7%) in group 3. The difference in IGT prevalence between the groups was statistically significant at P < .001. The prevalence of IGT was similar between acute and chronic plantar fasciitis at 78.9% and 80.6%, respectively. CONCLUSION: There was a very strong association between plantar fasciitis and IGT using group 3 as a reference. This study suggests that IGT should be actively sought out and managed in patients with plantar fasciitis. LEVEL OF EVIDENCE: Level II, cross-sectional cohort prospective study.

Use of locking barbed sutures in foot and ankle surgery. A case series.

BACKGROUND: Barbed sutures represent a novel technique for wound closure. By distributing tension forces across the length of a wound, it results in better wound healing. A recent article from Chowdhry et al. cautioned against the use of barbed sutures in foot and ankle surgery. Our experience with the Quill® (Angiotech, Vancouver, BC) barbed suture, showed a more positive outcome. MATERIALS AND METHODS: 123 surgical wounds were prospectively followed up after closure with a bidirectional barbed suture. The cohort represented a large range of patient ages and co-morbidities, as well as incision length and locations. RESULTS: Complication rates were low in this large cohort. The total complication rate was 6.5% (8 wounds). One wound (0.8%) had a major infection that needed further surgery, and 2 wounds (1.6%) showed inflammatory related complications. The remaining 5 wounds (4%) had minor wound complications, which resolved without any further surgical intervention. Patient satisfaction rates were high, with 78% of incisions scoring at maximum on the visual analogue cosmesis score. CONCLUSIONS: Use of the Quill® (Angiotech, Vancouver, BC) suture is a safe and effective alternative for wound closure in foot and ankle surgery.