Factors attributing to hip dislocations in adults who have sustained a # NOF

Date First Published:
August 28, 2014
Last Updated:
December 18, 2014
Report by:
Jennifer Sharples (In collaboration with the Orthopaedic Therapy Team) , Therapy Services (Central Manchester University NHS Foundation Trust)
Search checked by:
Orthopaedic Therapy Team, Central Manchester University NHS Foundation Trust
Three-Part Question:
In [adults who have sustained a # NOF] what [factors attribute] to [hip dislocations]?
Clinical Scenario:
Therapists assess and treat patients following surgery for fractured neck of femur (NOF). Hip precautions (no hip flexion above 90 degrees, no adduction beyond midline and no rotation of the operated leg) are routinely adhered to in those having undergone hemiarthroplasty and total hip replacement. This has time and cost implication for example waiting for equipment delivery for discharge can increase length of stay. To ensure that following hip precautions is evidenced based practice, the orthopaedic therapy team wanted to conduct a BestBETs.
Search Strategy:
Medline: exp FEMORAL NECK FRACTURES and HIP DISLOCATION
Limit to: publication year 2004-2014: English Language and (Age Groups All Adult 19 plus years)

CINAHL : exp (fractur* AND neck AND femur) or (femoral AND neck AND fracture) AND HIP DISLOCATION
Limit to publication year 2004-2014: (Language English) and (Age Groups All Adult)

Embase
exp FEMORAL NECK FRACTURES and HIP DISLOCATION. Limit to publication year 2004-2014: English Language and (Human Age Groups Adult 18 to 64 years or Aged 65+ years)
Outcome:
The literature search returned 249 journals of which 42 full text articles were considered appropriate for critical appraisal. The 4 journals below were relevant for inclusion. The other 39 journals were not included for a variety of reasons including; duplication, not relevant to the clinical question, data collected was pre 2004 or they were of very poor methodological quality.
Relevant Paper(s):
Study Title Patient Group Study type (level of evidence) Outcomes Key results Study Weaknesses
Direction of hip arthroplasty dislocation in patients with femoral neck fractures Enocson, A., Lapidus, G., Tornkvist, H., Tidermark, J. & Lapidus, L.J. -2009 Sweden 42 patients having undergone hemiarthroplasty for a # NOF Prospective study
(Level 3)
Risk of dislocation with anterolateral approach vs posterolateral approach. Clinically significant reduction in risk of dislocation with an anterolateral surgical approach. No documentation that hip precautions were followed.
No discussion of how many different surgeons operated
Risk factors for revision for early dislocation in total hip arthroplasty Conroy, J.L., Whitehouse, S.L., Graves, S.E., Pratt, N.L., Ryan, P. & Crawford,S. -2008 Australia 428 patients having dislocated following THR for # NOF Prospective review of Austrailian National Joint Registry
(Level 3)
Risk factors associated with dislocation with cemented vs uncemented prosthesis Increased risk of revision surgery following dislocation with 26mm head cementless acetabular component. Retrospective study over 5 years.
Dual mobility cups hip arthroplasty as a treatment for displaced fracture of the femoral neck in the elderly. Adam, P., Philippe, R., Ehlinger, M., Roche, O., Bonnomet, F., Mole, D. & Fessy, M.H. -2012 France 214 patients treated with a THR for fractured NOF with a dual mobility cup Multi-centre prospective study
(Level 3)
Dislocation rate 3 dislocations occurred of which all of these patients had undergone a posterior approach. However, results were not statistically significant Patients were not gender matched.
No long term follow up
Doesn’t discuss limitations of the study
Reduced dislocation rate after hip arthroplasty for femoral neck fractures when changing from posterolateral to anterolateral approach Skoldenburg, O., Ekman, A., Salemyr, M. & Boden, H. -2010 Sweden 372 cases in two groups (199 in 2007 and 173 in 2008) underwent fixation with either anterolateral or posterolateral approach A prospective study
(Level 3)
Dislocation rate There was a statistically significant reduction in rate of dislocation with the anterolateral approach. Overall dislocation rate for AL approach was 1% and PL approach was 9% 27 different surgeons operated
Both study groups had a mixture of AL and PL approaches. Groups were not matched.
Author Commentary:
5 papers were included in this report. All were prospective studies completed within Europe or Australasia. There were no studies satisfactory for inclusion completed within the UK. No studies looked directly at the effect of hip precautions on dislocation rate. All studies either compared different surgical approaches or different prostheses used. No studies mentioned whether hip precautions were followed post-operatively. An anterolateral surgical approach was associated with reduction in rate of dislocation compared to a posterolateral approach. Smaller head sizes in patients having received a THR was associated with lower dislocation rates than a larger head size. All studies were categorised as level 3 evidence. There were no randomised controlled trials relevant for inclusion.
Bottom Line:
There is no evidence to suggest that following hip precautions following a hemiarthroplasty or THR has an effect on dislocation rate.
Level of Evidence:
Level 3: Small numbers of small studies or great heterogeneity or very different population
References:
  1. Enocson, A., Lapidus, G., Tornkvist, H., Tidermark, J. & Lapidus, L.J.. Direction of hip arthroplasty dislocation in patients with femoral neck fractures
  2. Conroy, J.L., Whitehouse, S.L., Graves, S.E., Pratt, N.L., Ryan, P. & Crawford,S.. Risk factors for revision for early dislocation in total hip arthroplasty
  3. Adam, P., Philippe, R., Ehlinger, M., Roche, O., Bonnomet, F., Mole, D. & Fessy, M.H. . Dual mobility cups hip arthroplasty as a treatment for displaced fracture of the femoral neck in the elderly.
  4. Skoldenburg, O., Ekman, A., Salemyr, M. & Boden, H.. Reduced dislocation rate after hip arthroplasty for femoral neck fractures when changing from posterolateral to anterolateral approach