Author's reply

Sir,

We appreciate your interest¹ in our article² titled as “Primary total elbow arthroplasty”.

We have not locked the humeral and ulnar components before inserting them into the respective medullary canal; the ulnar component was inserted first then followed by humeral component in all the cases. After cement is hardened, humeral and ulnar components are assembled and fixed with hinge screw which was passed from the medial side of the elbow joint. There are slots on the medial side of the humeral hinge and on the lateral side of the ulnar hinge section which coincides with the slots on either side of the hinge screw and also in the alignment of the lock screw hole. This is confirmed by passing lock screw hole probe from anterior side of the joint laterally. After the confirmation of the lock screw hole, lock screw is passed in its hole and tightened completely. No doubt, working space from the anterior side is little after engaging the two components. However by experience, it becomes easier. Semi constrained\linked implants with pin-stabilized but loose, hinges avoid the potential for dislocation or subluxation.³,⁴,⁵ With Linked implants, disassembly of the components or breakage of the axle locking mechanism or disassociation of the components is a rare complication that may be the cause of implant failure. The vertical height of the prosthetic hinge was compared with the gap between the cut ends of the humerus and the ulna in both, extension and flexion. It may be necessary, to resects more bone from the distal humerus to accommodate the hinge, in patients with marked contractures of the flexors and extensors. Four sizes of prostheses are available like; extra small (dimension 13 × 7 mm), small (dimension 14 × 7 mm), medium (15 × 8 mm), large (16 × 8 mm), for right and left side.³ We have used the different sizes of prostheses depending upon the dimension of the medullary canal of ulna and humerus. We compared the length with the normal side postoperatively.