Epidemiology of Prosthetic Dislocation After Total Hip Replacement at a Tertiary Level Hospital, Tanzania

Njambilo, George M.; Haonga, Billy T.; Hussein, Mohamed M.; Mwanga, Joseph

doi:10.21608/EOJ.2025.431793

Epidemiology of Prosthetic Dislocation After Total Hip Replacement at a Tertiary Level Hospital, Tanzania

Document Type : Original Article

Authors

¹ Department of Orthopedics, Traumatology and Neurosurgery, Muhimbili University of Health and Allied Sciences (MUHAS), Muhimbili Orthopedic Institute (MOI), Dar es Salaam, Tanzania.

² Department of Orthopedics, Traumatology and Neurosurgery, Muhimbili University of Health and Allied Sciences (MUHAS), Tanzania.

10.21608/EOJ.2025.431793

Abstract

Background
Dislocation of the prosthesis is a serious complication after total hip replacement (THR) with the overall rate ranging between 0.2 and 10%. It is responsible for the higher rate of readmission; long hospital stays and the majority of early revision surgeries. A little is known about this topic in sub–Saharan Africa; This study aimed at addressing the knowledge gap on the epidemiology of prosthetic dislocation among patients who underwent THR in our locality.
Patients and Methods
A retrospective descriptive study was conducted at Muhimbili Orthopedics Institute among patients who had THR between 2016 and 2020. The standardized data extraction sheet was used to collect information on age, gender, indication for THR, surgical approach, type of prosthesis, presence of dislocation, mechanism for dislocation and time interval from surgery to dislocation.
Results
A total of 389 participants were enrolled, out of which 229(59%) were male and 160(41%) were female; all the patients underwent THR by direct lateral approach. Sixteen patients (4.1%) had a prosthetic dislocation, most of which occurred among male subjects (4.8%) P value= 0.4. Most dislocation occurred in those above 80 years (14.3%) P value= 0.02. Patients with the neck of femur fractures had highest rate of prosthetic dislocations (7.4%) when compared with the other indications of surgery (P value= 0.2). Most dislocations occurred within three months of surgery (68.7%), and the most common mechanism was spontaneous dislocation (56.3%).
Conclusions
The rate of prosthetic dislocation after THR is high in our setting; Majority are early and occur spontaneously. Age is significantly associated with occurrence of dislocation. Therefore, stratifying risk especially in elderly patients and extra precautions in early days following THR is important. Furthermore, prospective studies should be done on risk factors for dislocation after THR.

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