Diagnosing tarsal coalition in medieval Exeter.

OBJECTIVE: The objective of this study is to estimate the frequency and types of tarsal coalition represented in medieval remains from Exeter, England. MATERIALS: 183 individuals from the Cathedral Green site in Exeter, England. METHODS: Gross macroscopic analysis combined with radiographic examination and comparison with clinical and archaeological literature. RESULTS: Eight coalitions of various forms were ultimately identified; these include five calcaneonavicular, one talocalcaneal, one calcaneocuboid, and one lateral cuneiform-third metatarsal coalition. CONCLUSIONS: These frequencies are quite high for clinical imaging estimations, but consistent with other reported archaeological frequencies. SIGNIFICANCE: This study contributes to known frequencies of tarsal coalition in the past. It also provides descriptive diagnostic criteria for identifying tarsal coalition in archaeological populations. LIMITATIONS: Poor preservation of some of the individuals in this sample means that the true frequencies of tarsal coalition may be underrepresented. SUGGESTIONS FOR FURTHER RESEARCH: This study should be expanded to include more archaeological sites, especially medieval British sites, to determine overall prevalence rates. Additionally, the diagnostic criteria should be compared with other examples of known tarsal coalition to further our understanding of this rare pathology.

The "Double Medial Malleolus": A New Physical Finding in Talocalcaneal Coalition.

PURPOSE: It has been the observation of the senior author that there is a bony fullness or "double medial malleolus" over the middle facet as a consistent finding with most talocalcaneal coalitions (TCC). To document this observation, we reviewed records and radiographs in 3 patient groups. METHODS: Part 1: retrospective chart review was completed for 111 feet to determine the clinical presence of a palpable "double medial malleolus." Part 2: computed tomography (CT) scans for evaluation of tarsal coalition or symptomatic flatfoot between January 2006 and December 2014 were retrospectively reviewed for the same cohort. Soft tissue thickness was measured as the shortest distance between bone and skin surface at both the medial malleolus and the middle facet/coalition. The volume of the middle facet or coalition was measured at their midpoint. These findings were compared among feet with TCC (n=53), calcaneonavicular coalition (CNC) (n=20), and flatfoot (n=38). RESULTS: Part 1-clinical: from medical records, 38 feet (34%) had documented record of a palpable medial prominence. Of the feet reviewed with a "double medial malleolus," all had TCC (no false positives or false negatives). Clinical and CT prominence demonstrated significant correlation (rs=0.519, P=0.001). Part 2-radiographic: CT observation of "double medial malleolus" is significantly associated with TCC (P<0.001). CT observation of double medial malleolus is 81% sensitive and 79% specific as a predictive test for TCC. The middle facet-to-skin distance was significantly closer in those with TCC versus controls (P<0.001). The ratio was larger in patients with TCC versus CNC (P=0.006) or flatfeet (P<0.001). Volume was nearly twice the size in patients with TCC versus the controls (P<0.001). CONCLUSIONS: TCCs have a bony prominence below the medial malleolus on clinical exam and CT scan not present in flatfeet or CNCs. This abnormal middle facet is almost twice the size of the normal middle facet. Obesity or severe valgus may mask this finding. If a palpable bony prominence is noted just below the medial malleolus during examination of a painful foot with a decrease in subtalar motion, the likely diagnosis is TCC. With this added clinical finding, appropriate images can be ordered to confirm the diagnosis of the latter. We advise CT scans with 3D images for surgical planning. The primary finding for tarsal coalitions in textbooks is decreased subtalar motion. This new finding of a palpable enlarged medial prominence just below the medial malleolus is highly associated with TCCs. LEVEL OF EVIDENCE: Level III.

Tarsal tunnel disease and talocalcaneal coalition: MRI features.

OBJECTIVE: To assess, utilizing MRI, tarsal tunnel disease in patients with talocalcaneal coalitions. To the best of our knowledge, this has only anecdotally been described before. MATERIALS AND METHODS: Sixty-seven ankle MRIs with talocalcaneal coalition were retrospectively reviewed for disease of tendons and nerves of the tarsal tunnel. Interobserver variability in diagnosing tendon disease was performed in 30 of the 67 cases. Tarsal tunnel nerves were also evaluated in a control group of 20 consecutive ankle MRIs. RESULTS: Entrapment of the flexor hallucis longus tendon (FHL) by osseous excrescences was seen in 14 of 67 cases (21 %). Attenuation, split tearing, tenosynovitis, or tendinosis of the FHL was present in 26 cases (39 %). Attenuation or tenosynovitis was seen in the flexor digitorum longus tendon (FDL) in 18 cases (27 %). Tenosynovitis or split tearing of the posterior tibial tendon (PT) was present in nine cases (13 %). Interobserver variability ranged from 100 % to slight depending on the tendon and type of disease. Intense increased signal and caliber of the medial plantar nerve (MPN), indicative of neuritis, was seen in 6 of the 67 cases (9 %). Mildly increased T2 signal of the MPN was seen in 15 (22 %) and in 14 (70 %) of the control group. CONCLUSIONS: Talocalcaneal coalitions may be associated with tarsal tunnel soft tissue abnormalities affecting, in decreasing order, the FHL, FDL, and PT tendons, as well as the MPN. This information should be provided to the referring physician in order to guide treatment and improve post-surgical outcome.

Posteromedial Ankle Impingement Caused by Hypertrophy of Talocalcaneal Coalition: A Report of Five Cases and Introduction of a Novel Index System.

Ankle impingement syndromes are common disorders that can be attributed to many factors. To the best of our knowledge, posteromedial ankle impingement syndromes caused by talocalcaneal coalition have never been previously reported. The present report describes 5 patients with posteromedial ankle pain and inversion limitation. The physical examination, radiographic, and magnetic resonance imaging findings suggested posteromedial ankle impingement syndrome and talocalcaneal coalition. The 5 patients underwent surgery after conservative treatment had failed. A novel index system, namely the angle and thickness of the medial talocalcaneal facet, was introduced. The talocalcaneal coalitions protruded medially and impinged on the malleolus medialis. The medial facet of the talus and calcaneum had a wider angle and thickness than normal. Pain relief was noted, and good long-term outcomes were achieved after resection of the medial prominence and coalition in all 5 patients. Talocalcaneal coalition can cause posteromedial ankle impingement syndrome when the coalition is hypertrophic. The angle and thickness of the medial talus facet could be a simple index to diagnose this disorder.