Advanced merger talks between Smith & Nephew and Johnson & Johnson’s orthopaedics unit, DePuy Synthes, have collapsed. The reported sticking point was a disagreement over who would lead the combined company, which was valued at $34 billion.

Johnson & Johnson sought to appoint Namal Nawana, head of its orthopaedics division and a former Smith & Nephew CEO, to lead the new company. Smith & Nephew insisted that its current CEO, Deepak Nath, remain in charge, making the leadership issue a deal-breaker.

The proposed transaction would have valued Johnson & Johnson’s hip and knee replacement business at as much as $22 billion. The financial terms were reportedly aligned, but the leadership dispute derailed the deal. Both companies have declined to comment on the reports.