Introduction

Pancarpal arthrodesis (PCA) is most commonly performed with a dorsally placed bone plate combined with a period of adjunctive external coaptation. A novel PCA plate (CastLess PCA plate, Orthomed Ltd, UK) has been developed which may obviate the requirement for external coaptation. The aim of this retrospective study was to review use of this implant in clinical cases.

Materials and Methods

Records of patients undergoing PCA using a 3.5/2.7mm CastLess PCA plate between September 2006 and July 2007 were reviewed. Cases included in the study had to have complete case records and at least one clinical and radiographic follow up examination. Intra and postoperative complications, metacarpal coverage, use of external coaptation, and lameness were recorded. Final follow up was obtained by telephone owner assessment.

Results

Nine dogs underwent unilateral and 2 dogs underwent bilateral PCA. The median age and weight of the study group were 3.4 years (range 1.5-12years) and 32.8kg (range 18.4-46kg) respectively. Iatrogenic fissure fracture of metacarpals 3 (2) and 4 (1) were created in 2 cases during screw tightening. 1 alignment pin could not be removed. Distal plate position was suboptimal in 2 procedures. Median metacarpal coverage was 85.2% (range 75.8-92.5 %). External coaptation was used in 4 cases (1 bilateral PCA, 2 intra-operative metacarpal fractures, 1 preoperative metacarpal 2 fracture) for a median of 4 weeks (range 3-6 weeks). 7 cases (9 procedures) had a soft dressing applied for a median of 10 days (range 7-14 days). Initial follow up evaluation was performed at a median of 6 weeks (range 6-24 weeks). Postoperative infection developed in 1 case. Radiographs showed no screw loosening, no metacarpal bone fractures and developing arthrodesis in all cases. Iatrogenic metacarpal fractures had healed. 2 dogs had no lameness, 6 had mild lameness and 3 had moderate lameness. Telephone follow up in 10 cases was obtained at a median of 8.5 months postoperatively (range 3-13 months). 6 dogs were not lame. 4 had mild lameness in their operated limbs, including both patients who had bilateral PCA.

Conclusion

These results indicate that a CastLess PCA plate can result in good to excellent limb function and removes the need for adjunctive external coaptation. Development of postoperative screw loosening and metacarpal fracture were not identified. Care should be taken during application of the distal portion of the plate.