Report on 6 individuals, occurring in three successive generations of a single family, who were affected by "classical" tricho-rhino-phalangeal syndrome type I. Besides pear-shaped noses, enlarged philtrum, hypotrichosis, premature alopecia, coned epiphysis at the proximal interphaleangeal joints with consecutive ulnar deviation of the long fingers, dysostotic feet, Perthes-like hip dysplasia with multilocated joint laxity and hyposomia were impressing. Height was 168 cm, corresponding to the 50 (th) percentile. Radiographs and 3D-reconstruction of both hands showed asymmetrical brachymetacarpia, brachymesophalangia and painful invaginations of the middle phalanx bases (type 12 according to Giedion). Angular deformities are seen predominantly in the index finger decreasing to the ring finger. Painful cone-shaped epiphyses with ulnar dislocation of the PIP joints were stabilized following resection arthrodesis with tension band osteosynthesis. At reexamination 48 months postoperatively a painfree and powerful pinch grip function of both hands was restored. All family members who showed the phenotypical features of TRPS type I revealed in genetic analysis also identical mutations. Inside the exon 4 in position 1831 there was a nonsens mutation C --> T. Non-afflicted relatives did not show this mutation.