Soft tissue restricts impingement-free mobility in total hip arthroplasty

• Published in: International orthopaedics Vol. 41; no. 2; pp. 277 - 282
• Main Authors: Woerner, Michael, Weber, Markus, Sendtner, Ernst, Springorum, Robert, Worlicek, Michael, Craiovan, Benjamin, Grifka, Joachim, Renkawitz, Tobias
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.02.2017
• Subjects: Aged; Arthroplasty, Replacement, Hip - adverse effects; Arthroplasty, Replacement, Hip - methods; Female; Hip Joint - physiopathology; Hip Joint - surgery; Humans; Joint Dislocations - surgery; Male; Medicine; Medicine & Public Health; Middle Aged; Minimally Invasive Surgical Procedures - adverse effects; Minimally Invasive Surgical Procedures - methods; Original Paper; Orthopedics; Osteoarthritis, Hip - surgery; Prospective Studies; Range of Motion, Articular - physiology; ROM; Navigation; Soft Tissue; Impingement; Total hip arthroplasty; Minimally invasive
• ISSN: 0341-2695; 1432-5195
• DOI: 10.1007/s00264-016-3216-1

Purpose Impingement is a major source for decreased range of motion (ROM) and dislocation in total hip arthroplasty (THA). In the current study we analyzed the impact of soft tissue impingement on ROM compared to bony and/or prosthetic impingement. Methods In the course of a prospective clinical trial 54 patients underwent cementless total hip arthroplasty in the lateral decubitus position using imageless navigation. The navigation device enabled intra-operative ROM measurements indicating soft tissue impingement. Post-operatively, all patients received postoperative 3D-CT. Absolute ROM without bony and/or prosthetic impingement was calculated with the help of a collision-detection-algorithm. Results Due to soft tissue impingement we found a reduced ROM of over 20° ( p  < 0.001) compared to bony and/or prosthetic impingement regarding flexion, extension, abduction and adduction and of over 10° regarding external rotation ( p  < 0.001). In contrast, soft tissue impingement showed less impact on internal rotation in 90° of flexion ( p  = 0.76). Multivariate analysis showed an association between BMI and flexion, whereas all other ROM directions were independent of BMI. Conclusions Soft tissue has a major impact on impingement-free ROM after THA. For the majority of movements, soft tissue restrictions are more important than bony and prosthetic impingement. Future models of patient individual joint replacement including pre-operative (CT) planning and intra-operative navigation should include algorithms additionally accounting for soft tissue impingement.