Influence of Kinematics on the Calculation of Hip Joint Reaction Forces in Patients with Symptomatic Leg Length Inequality following Total Hip Replacement (original) (raw)
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Clinical biomechanics (Bristol, Avon), 2015
Symptomatic leg length inequality accounts for 8.7% of total hip replacement related claims made against the UK National Health Service Litigation authority. It has not been established whether symptomatic leg length inequality patients following total hip replacement have abnormal hip kinetics during gait. Hip kinetics in 15 unilateral total hip replacement patients with symptomatic leg length inequality during gait was determined through multibody dynamics and compared to 15 native hip healthy controls and 15 'successful' asymptomatic unilateral total hip replacement patients. More significant differences from normal were found in symptomatic leg length inequality patients than in asymptomatic total hip replacement patients. The leg length inequality patients had altered functions defined by lower gait velocity, reduced stride length, reduced ground reaction force, decreased hip range of motion, reduced hip moment and less dynamic hip force with a 24% lower heel-strike pea...
Hip joint load in relation to leg length discrepancy
Medical Devices: Evidence and Research, 2008
Leg length discrepancy is common both in healthy subjects and after total hip arthroplasty (THA). Studies that evaluated leg length following THA have demonstrated a notable inconsistency in restoring leg length. The effects concerning joint load during gait is however not well known. The purpose of this study was to use three-dimensional (3D) gait analysis to evaluate joint load during gait with a simulated leg length discrepancy of 2 and 4 cm. Nine healthy subjects without any history of hip injury participated. Method: A 3D gait analysis (Vicon, Motion System, Oxford, England) was performed with 6 cameras and 2 force palates using a standard biomechanical gait model. Hip joint moments of force were calculated for all three degrees of motion freedom. ANOVA for repeated measurements was used for statistical calculations. Results: Abduction peak moment was signifi cantly increased at the short side (P Ͻ 0.05) but unaffected on the long side. The adduction moment decreased on the long side between 0 and 4 cm (P Ͻ 0.01) but was unaffected on the short side. The internal hip rotation moments were unchanged for both the long and the short side. The external rotation moment was unchanged on the short side and decreased between bare foot and 4 cm on the long side (P Ͻ 0.05). Conclusion: A leg length discrepancy of 2 cm or more creates biomechanical changes concerning hip joint load both on the long and the short side and that the effects are larger on the short side. The increased stress may cause problems in the long run.
The importance of leg length discrepancy after total hip arthroplasty
Journal of Bone and Joint Surgery - British Volume, 2005
We assessed leg length discrepancy and hip function in 90 patients undergoing primary total hip arthroplasty before surgery and at three and 12 months after. Function was measured using the Oxford hip score (OHS). After surgery the mean OHS improved by 26 points after three months and by 30 points after 12.
Prevalence and functional impact of patient-perceived leg length discrepancy after hip replacement
International Orthopaedics, 2009
The aim of this survey was to determine the prevalence of patient-perceived leg length discrepancy (LLD) after primary total hip replacement (THR) and its impact on functional outcome. All consecutive patients who had a primary, unilateral THR at one orthopaedic centre between April 1993-1996 were sent a questionnaire which included the Oxford hip score (OHS) and questions about LLD. A total of 1,114 patients returned completed questionnaires. Three hundred and twenty nine patients (30%) reported a LLD. Of these patients, 161 patients (49%) were bothered by the difference, 101 patients (31%) used a shoe raise and 13 patients (4%) thought that the surgery had not been worthwhile. Patients with a LLD had a significantly poorer OHS (p<0.001) and limped more frequently. This study found that a third of patients perceived a LLD at 5-8 years after THR and LLD had a significant negative impact on functional outcome.
A PROSPECTIVE STUDY ANALYSIS OF LIMB LENGTH DISCREPANCY FOLLOWING TOTAL HIP ARTHROPLASTY
Asian Journal of Pharmaceutical and Clinical Research, 2021
Objective: The present study was designed and implemented to assess the incidence and occurrence of LLD in post-hip arthroplasty and also to evaluate the causes of limb length discrepancy both intra- and post-operative period to manage total hip arthroplasty effectively. Methods: It is a prospective study involving 52 patients underwent for THA and conducted in the Department of Orthopedics, Tertiary Care Hospital, Visakhapatnam, India from the period of January 2013 to December 2019. The study used Southern approach or “Moore” approach. All the patients are assessed for limb length discrepancy immediately after the surgery and followed at 6 weeks, 3 months, and after 6 years. Results: Three patients had significant limb length discrepancy among the 52 patients (5.77%) while the remaining had no significant discrepancies in all X-rays which assess the radiological discrepancies in length. The study yields a satisfactory result as very few patients reported LLD during follow-up period and outcomes such as pain alleviation, walking capacity, limping, and patient satisfaction were insignificantly influenced by leg lengthening (p≤0.05). Conclusion: A combination of pre-operative templating, intra-operative marking and usage of intra-operative image intensifier and an understanding of anatomy, biomechanics of hip, and implant design would reduce the error of limb length discrepancy.
Gait & posture, 2016
We aimed to investigate the relationship between postoperative leg length/offset (LL/OS) reconstruction and gait performance after total hip arthroplasty (THA). In the course of a prospective randomized controlled trial, 60 patients with unilateral hip arthrosis received cementless THA through a minimally-invasive anterolateral surgical approach. One year post-operatively, LL and global OS restoration were analyzed and compared to the contralateral hip on AP pelvic radiographs. The combined postoperative limb length/OS reconstruction of the operated hip was categorized as restored (within 5mm) or non-restored (more than 5mm reduction or more than 5mm increment). The acetabular component inclination, anteversion and femoral component anteversion were evaluated using CT scans of the pelvis and the femur. 3D gait analysis of the lower extremity and patient related outcome measures (HHS, HOOS, EQ-5D) were obtained pre-operatively, six months and twelve months post-operatively by an obse...
The Journal of Arthroplasty, 2015
We investigated whether patients with lengthening (N 9 mm), restoration (between 9 mm lengthening and 5 mm shortening) or shortening (N 5 mm) of the operated leg after total hip arthroplasty (THA) had different function (WOMAC score), quality of life (EQ-5D), residual hip pain, use of shoe lift and walking aid and leg length discrepancy (LLD) awareness, 12-15 months postoperatively. All patients had a significant postoperative improvement in WOMAC and EQ-5D regardless the LLD. However, the lengthening group showed less improvement in WOMAC, more use of shoe lift, residual hip pain and LLD awareness compared with the other two groups. No differences in EQ-5D were found. In spite of the improvement in function and quality of life, lengthening had adverse effects and should therefore be avoided.
The bone & joint journal, 2015
We evaluated an operative technique, described by the Exeter Hip Unit, to assist accurate introduction of the femoral component. We assessed whether it led to a reduction in the rate of leg-length discrepancy after total hip arthroplasty (THA). A total of 100 patients undergoing THA were studied retrospectively; 50 were undertaken using the test method and 50 using conventional methods as a control group. The groups were matched with respect to patient demographics and the grade of surgeon. Three observers measured the depth of placement of the femoral component on post-operative radiographs and measured the length of the legs. There was a strong correlation between the depth of insertion of the femoral component and the templated depth in the test group (R = 0.92), suggesting accuracy of the technique. The mean leg-length discrepancy was 5.1 mm (0.6 to 21.4) pre-operatively and 1.3 mm (0.2 to 9.3) post-operatively. There was no difference between Consultants and Registrars as prima...
Functional leg-length inequality following total hip arthroplasty
The Journal of Arthroplasty, 1997
A consecutive series of 100 patients undergoing primary total hip arthroplasty were assessed for functional leg-length inequality (FLLI). In addition, the medical records of all patients treated for FLLI by the senior author (C.S.R.) in the past 15 years was reviewed. A questionnaire was distributed to the members of The Hip Society specifically to query the prevalence, etiology, and management of FLLI. Fourteen percent of patients were noted to have pelvic obliquity and FLLI 1 month after surgery. All had resolution of the symptoms by 6 months after surgery. Nine patients have been identified over the past 15 years with persistent FLLI. Among the causes suggested by respondents to the questionnaire are tightness of periarticular soft tissues with resultant pelvic obliquity and degenerative conditions of the spine with contracture. Methods of treatment and prevention are discussed.