Introduction Medial column insufficiency in patients with painful acquired flatfoot can be difficult to appreciate. The reverse Coleman block test (as described and published by Mr E Wood in 2009) is used in this study to predict medial column instability.

Methods Patients who underwent a procedure for medial column insufficiency with use of the reverse Coleman block test pre-operatively were investigated. Weight bearing radiographs were used to determine the joints in the medial column contributing to the deformity and also to estimate the angle which the first ray must be depressed to re-establish hindfoot neutrality. The reverse Coleman block test corrects a mobile valgus heel to a neutral position by placing a block, of appropriate height, under the first metatarsal head. With the heel in neutral and the relative forefoot supination compensated the foot returns to a neutral anatomic position. Gender, age, complications and radiological outcomes were investigated.

Results Over the last three years 25 medial column procedures were performed for painful insufficiency on 17 females and five males by the senior author. Three patients underwent staged bilateral procedures. The average age was 62 years old. Three feet had been on operated on the medial column previously. The pre-operative weight bearing lateral radiographs showed instability in the medial column greater than 5° in 12 cases. With the reverse Coleman block test instability was seen in 25 cases and the deformity increased from an average of 7° (range 0° to 25°) to 14° (range 5° to 30°). Post-operative weight bearing radiographs, with fusion of the unstable joint, the average medial column alignment was 1° (range -10° to 10°). Three patients developed superficial infections requiring oral antibiotics for treatment. One patient had a non-requiring revision surgery.

Discussion The reverse Coleman block test revealed instability in 13 out of 27 cases not seen with simple weight bearing lateral radiographs. The test also on average doubled the size of any deformity seen. This aided pre-operative planning to predict the scale of deformity correction required.

Conclusion The reverse Coleman block test is a useful test to determine medial column insufficiency and assist with pre-operative planning.