Total Hip Arthroplasty: Leg Length Discrepancy Affects Functional Outcomes and Patient’s Gait

Abstract

Our study was targeted to investigate the relationship between postoperative leg length discrepancy (LLD) and the outcomes of total hip arthroplasty (THA) including gait, hip function, and lower back pain (LBP). Ninety-two patients who underwent primary THA during Jan 2009 to Apr 2011 in our medical center were enrolled in this study. We measured postoperative LLD of the patients both directly and from the leg radiographs. Six months after the surgery, we evaluated the hip function with Harris Hip Score (HHS), analyzed the gait, and recorded the degree of LBP. Patients with LLD between 10 and 20 mm were given the block footbeds to correct the difference in the leg length. Then 1 year after the surgery, the above-mentioned parameters were evaluated again. (1) LLD: Patients were divided into three groups according to the magnitude: less than 10 mm were grouped as A, those between 10 and 20 mm as B, and more than 20 mm as C. (2) Gait analysis: patients with larger LLD showed slower gait speed (t = 6.527; p < 0.01), longer single support time (t = -2.665; p = 0.01), and shorter foot-off time (t = -8.502; p < 0.01). After half a year of the surgery, Group B patients showed recovery and their functional performance was not significantly different from that of the patients in Group A (t = -0.686; p = 0.49). (3) HHS: In the first half of the follow-up year, patients with smaller LLD showed an improved function (t = 6.56; p < 0.01). At the end of year one, the HHS of Group B patients was not significantly different from that of Group A (t = 1.4; p = 0.16), suggesting a good recovery, however, Group C patients showed no improvement in HHS scores. (4) LBP: Initially, Group B patients suffered from more severe LBP than Group A patients, however, the examination conducted in the end of year 1 exhibited no difference in the LBP levels of the two groups (t = 0.683; p = 0.01, t = -0.85; p = 0.40). After THA surgery, the outcome was found to be significantly associated with the degree of different length of lower limbs. The use of block such as footbed could partly relieve the symptoms of hip dysfunction and LBP. However, the recovery was less significant in patients with leg length difference more than 20 mm.

The Application of Improved Position for Lower Limb full Length DR Radiograph in Hip/Knee Arthroplasty

“…When traditional standing position cannot be applied, the normal angle of lower limb mechanical axis passes the center of the tibial plateau is around 57.8% [6,7], which is one of the important standard value to assess arthroplasty surgery. Another important standard value is the mechanical deviation between the lower limb mechanical axis and the center of the tibial plateau, of which less than 5 mm defines excellent and 5-10 mm defines normal [8][9][10]. Using different position for DR images results greatly different measured data, and our results show that the application of improved position is more suited for arthroplasty surgeries.…”

Chronic traumatic ankle and foot osteomyelitis: a nationwide case-control study

“…Soft, custom-made insoles alleviate pain by reducing the sole parts that are under pressure. In addition, limping while walking results from leg length discrepancy (LLD) in more than half of the study group, which causes pain and damage to the spine [ 19 ]. Insoles that provide additional height can compensate for LLD, and the secondary effects can mostly be eliminated [ 20 ].…”

The association of leg length and offset reconstruction after total hip arthroplasty with clinical outcomes

“…Although proper implant reconstruction improves the biomechanical function of the hip, existing evidence on the association with clinical outcomes is not consistent. Several studies using patientreported outcome measures (PROMs) have found no association with radiographic measurements after THA (1, [8][9][10][11][12][13][14] whereas others have reported marginally significant correlations (7,9,15,16). In addition to PROMs, functional tests can be used to assess outcomes after THA.…”

“…Asayama et al (5) demonstrated that a 15% decrease in femoral offset generates weakness of the abductor muscles and correlates with the frontal plane tilt angle of the pelvis during the Trendelenburg test (17). Sariali et al (18) found significant gait alterations in patients with more than 15% decreased postoperative femoral offset while Zhang et al (16) and Li et al (19) reported significant gait alterations between patients with variable LLD after THA. Because PROMs are subjective measures, suffer from a ceiling effect, and may lack sufficient sensitivity to demonstrate a difference in clinical outcomes (18,20), functional tests may be better discriminators to capture functional impairments in relation to changes of the reconstructed hip joint position after THA.…”